Blu-ray Technology
Thread Rating:
  • 1 Vote(s) - 4 Average
  • 1
  • 2
  • 3
  • 4
  • 5
electronics seminars
Active In SP
**

Posts: 694
Joined: Nov 2009
#1
28-12-2009, 04:16 PM



.doc   blu-ray.doc (Size: 136 KB / Downloads: 805)
ABSTRACT
Blu-ray, also known as Blu-ray Disc (BD) is the name of a next-generation optical disc video recording format jointly developed by nine leading consumer electronics companies. The format was developed to enable recording, rewriting and playback of high-definition video (HDTV). Blu-ray makes it possible to record over 2 hours of digital high-definition video (HDTV) or more than 13 hours of standard-definition video (SDTV/VHS picture quality) on a 27GB disc. There are also plans for higher capacity discs that are expected to hold up to 50GB of data.
The Blu-ray Disc technology can store sound and video while maintaining high quality and also access the stored content in an easy-to-use way. Adoption of the Blu-ray Disc in a variety of applications including PC data storage and high definition video software is being considered.
Key Characteristics of Blu-ray discs are :

1. INTRODUCTION
Blu-ray is a new optical disc standard based on the use of a blue laser rather than the red laser of todayâ„¢s DVD players. The standard, developed collaboratively by Hitachi, LG, Matsushita (Panasonic), Pioneer, Philips, Samsung, Sharp, Sony, and Thomson, threatens to make current DVD players obsolete. It is not clear whether new Blu-ray players might include both kinds of lasers in order to be able to read current CD and DVD formats.
The new standard, developed jointly in order to avoid competing standards, is also being touted as the replacement for writable DVDs The blue laser has a 405 nanometer (nm) wavelength that can focus more tightly than the red lasers used for writable DVD and as a consequence, write much more data in the same 12 centimeter space Like the rewritable DVD formats, Blu-ray uses phase change technology to enable repeated writing to the disc.
Blu-rayâ„¢s storage capacity is enough to store a continuous backup copy of most peopleâ„¢s hard drives on a single disc. The first products will have a 27 gigabyte (GB) single-sided capacity, 50 GB on dual-layer discs. Data streams at 36 megabytes per second (Mbps), fast enough for high quality video recording Single-sided Blu-ray discs can store up to 13 hours of standard video data, compared to single-sided DVDâ„¢s 133 minutes. People are referring to Blu-ray as the next generation DVD, although according to Chris Buma, a spokesman from Philips (quoted in New Scientist) Except for the size of the disc, everything is different.
Blu-ray discs will not play on current CD and DVD players, because they lack the blue-violet laser required to read them. If the appropriate lasers are included, Blu-ray players will be able to play the other two formats. However, because it would be considerably more expensive, most manufacturers may not make their players backward compatible. Panasonic, Philips, and Sony have demonstrated prototypes of the new systems.
2. EVOLUTION OF OPTICAL REMOVABLE MEDIA STORAGE DEVICES
2.1 Optical Storage
Optical RMSD formats use a laser light source to read and/or write digital data to a disc. Compact disc (CD) and digital versatile disc (DVD, originally referred to as digital video disc) are the two major optical formats. CDs and DVDs have similar compositions consisting of a label, a protective layer, a reflective layer (aluminum, silver, or gold), a digital-data layer molded in polycarbonate, and a thick polycarbonate bottom layer.

Fig.2.l.1 Composition of optical disk
CD Formats include
¢ Compact disc-read only memory (CD-ROM)
¢ Compact disc-recordable (CD-R)
¢ Compact disc-rewritable (CD-RW)
DVD formats include
¢ Digital versatile disc-read only memory (DVD-ROM)
¢ Digital versatile disc-recordable (DVD-R)
¢ DVD-RAM (rewritable)
¢ Digital versatile disc-rewritable (DVD-RW)

2.1.1 CD-ROM
Data bits are permanently stored on a CD as a spiral track of physically molded pits in the surface of a plastic data layer that is coated with reflective aluminum. Smooth areas surrounding pits are called lands. CDs are extremely durable because the optical pickup (laser light source, lenses and optical elements, photoelectric sensors, and amplifiers) never touches the disc. Because data is read through the thick bottom layer, most scratches and dust on the d surface are out of focus, so they do not interfere with the reading process.
With a 650-MB storage capacity (sometimes expressed as ˜74 minutes,™ referring to audio playing time encoded in the original CD format), one CD-ROM disc can store the data from more than 450 floppy disks. Data access speeds are reasonable, with random access rates ranging from 80 to 120 ms for any data byte on the disc. Maximum data transfer rates are approximately 6 MB/sec. These attributes make CD-ROMs especially well suited for storing large multimedia presentations and software programs.
CD-ROM drives are distinguished by different disc rotation speeds measured relative to the speed of an audio CD player. A 1X CD-ROM accesses data at approximately 150 KB/sec, the same as an audio player. A 32 X CD-ROM reads data thirty-two times faster at approximately 4,800 KB/sec. In general, faster speeds reduce data access time, but vibration and noise problems limit maximum speeds to approximately 48X.

2.1.2 CD-R.
CD-R drives advanced a write once/read many (WORM) storage technology that appeared in the mid 1980s. CD-R drive production ended when the cost to manufacture CD-RW drives became comparable. CD-R discs accept multiple writing sessions to different sections of a disc. However, CD-ROM drives must be multi-session compatible to read any data recorded after the first writing session; all of todayâ„¢s CD-ROM drives meet this requirement.
CD-R discs use a photosensitive dye layer that can be changed (or Ëœboundedâ„¢) with a laser to simulate the molded pits of a conventional CD. The dye layer is relatively transparent until it is burned with a laser to make it darker and less reflective. CD-R discs use a gold or silver reflective layer behind the dye to produce reflectives similar to the aluminum layer used in CDs.
When a CD-R disc is read, the lands reflect laser light off of the gold or silver layer through the more transparent areas of the dye. The less reflective areas, produced from recording data on the dye, read as pits.
Like CD-Rom discs, recordable discs have 650 MB ( or 74 minutes) of storage capacity. The actual capacity of a 650-MB CD-R disc is about 550 MB when they are formatted for packet writing. Higher-capacity CD-Rs that have become available recently include:
¢ 700 MB (80 minutes)
¢ 800 MB (90 minutes)
¢ 880 MB (99 minutes)
The 700MB disc is the only higher-capacity option that is fully compatible with the CD-R standard CD-R drives provide reasonable average data access times typically less than 100 ms. CD-R discs are the least expensive RMSD media available, but the CD-R systems are limited as RMSDâ„¢s because they can only be written once.
2:1.3 CD-RW
CD-RW drives introduced in 1997, record data on both CD-R and CD-RW discs. CD-R.W discs use a phase-change technology to record. In place of the dye layer use din CD-R media, CD-RW discs have an alloy layer composed of antimony, tellurium, and other metals that exists in either of two stable states. This material forms a polycrystalline structure when heated above 200 degree Celsius and cooled, but also forms an amorphous or non-crystalline structure when heated above the melting point at 500 to 700 degrees Celsius and rapidly cooled. The alloy is changed between the two states using two different laser power settings.
The crystalline state for this material reflects more light than the non-crystalline form, so it simulates the lands of a regular CD. Data bits are encoded by changing small target areas to the non-crystalline form. This writing process can be repeated approximately 1,000 times per disc.
CD-RW drives write to both CD-R and CD-RW media, and permit multiple writing sessions to different sections of a disc. CD-RW drives are specified by CD-R write speed, CD-RW write speed, and CD-ROM maximum read speed (for example, 8/4/32Xis 8X CD-R write/4X CD-RW write/32X CD-ROM maximum read). The fastest CD-RW drives now provide 16/10/40X speeds for desktop systems. Transfer rates for reading data are up to 6 MB/sec and approximately 2.4 MB/sec for writing data on CD-R media.
Like the CD-R discs, the actual capacity of a 650-MB CD-RW disc is about 550 MB when formatted for packet writing. CD-RW drives have replaced the comparably priced CD-R drives, and are positioned to be a good RMSD solution.
2.1.4 DVD
Like CD drives, DVD drives read data through the disc substrate, reducing interferences from surface dust and scratches. However, DVD-ROM technology provides seven times the storage capacity of CD discs, and accomplishes most of this increase by advancing the technology used for CD systems. The distance between recording tracks is less than half that used for CDs. The pit size also is less than half that on CDs, which requires a reduced laser wavelength to read the smaller-sized pits. These features alone give DVD-ROM discs 4.5 times the storage capacity of CDs;
2.1.4.1 Single Layers and Dual Layers
DVD discs have a much greater data density than CD discs, and DVD-ROM drives rotate the disc faster than CD drives. This combination results in considerably higher throughput for DVD technology. A 1X DVD-ROM drive has a data transfer rate of 1,250 KB/sec compared with a 150-KB/sec data transfer rate for a 1X CD-ROM drive. Current DVD-Rom drives can read DVD discs at 16X (22 MB/sec) maximum speeds and can read CDs at 48X (7.5 MB/sec) maximum speeds.
DVD-ROM discs provide a 4.7-GB storage capacity for single-sided, single data-layer discs. Single-sided, double data-layer discs increase the capacity to 8.5 GB. Double-sided, single data layer discs offer 9.4 GB, and double-sided, double data-link layer discs provide 17 GB of storage capacity. DVD-ROM drives also read CD-ROM, CD-R, CD-RW, and DVD-R discs. As new software programs push the storage limits for CD-ROM discs.
21.4.2 DVD Storage Versions
2.1.4.2.1 DVD-R
DVD-R drives were introduced in 1997 to provide write-once capability on DVD-R discs used or producing disc masters in software development and for multimedia post-production. This technology, sometimes referred to as DVD-R for authoring, is limited to niche applications because drives and media are expensive.
DVD-R employ a photosensitive dye technology similar to CD-R media. At 3.94 GB per side, the first DVD-R discs provided a little less storage capacity than DVD-ROM discs. That capacity as now been extended to the 4.7 GB capacity of DVD-ROM discs.
The IX DVD-R data transfer rate is 1.3MB/sec. Most DVD-ROM drives and DVD video players read DVD-R discs. Slightly modified DVD-R drives and discs have recently become available for general use.

2.1.4.2.2 DVD-RAM
DVD-Ram (rewritable) drives were introduced in 1998. DVD-Ram devices use a phase-change technology combined with some embossed land/pit features. Employing a format termed Ëœland groove,â„¢ data is recorded in the grooves formed on the disc and on the lands between the grooves. The initial disc capacity was 2.6 GB per side, but a 4.7-GB-per-side version is now available.
Each DVD-RAM disc is reported to handle more than 100,000 rewrites. DVD is specifically designed for PC data storage; DVD-RAM discs use, a storage structure based on sectors, instead of the spiral groove structure used for CD data storage. This sector storage is similar to the storage structure used by hard drives. Sector storage results in faster random data access speed.
Because of their high cost relative to CD-RW technology, current consumer-oriented DVD RAM drives and media is not a popular choice for PC applications. Slow adoption of DVD-Ram reading capability in DVD-ROM drives has also limited DVD-RAM market acceptance.
2.1.4.2.3 DVD-RW
The DVD-RW drive format is similar to the DVD-R format, but offers rewritability using a phase-change recording layer that is comparable to the, phase-change layer used for CD-RW. DVD-RW is intended for consumer video (non-PC) use, but PC applications are also expected for this technology. The first DVD-RW drives bases on this format, which also record DVD-R discs, were introduced in early 2001.
2.2 DVD vs. CD
DVD has a more efficient error correction code (ECC). Fewer data bits are required for error detection, thus freeing space for recorded data. DVD discs can also store two layers of data on a side by using a second data layer behind a semitransparent first data layer laser to switch between the two data layers.
DVD drives can also store data on both sides of the disc. Manufacturers deliver the two-sided structure by bonding two thinner substrates together, providing the potential to double a DVDâ„¢s storage capacity. Single-sided DVD disc have the two fused substrates, but only one side contains data.
CD-RW and DVD-ROM combination
A combination CD-RW/DVD-R0M device, commonly called a ËœComboâ„¢ drive, has been available since 1999. Combo drives need a high-power laser for CD-R/CD-RW writing, and a different laser and decoding electronics for reading DVDs. A Combo drive provides additional functionality for PCs, and is especially valuable for space-constrained portable systems.
Comparison table
Floppy disk Compact disc (CD) Digital Video Disc (DVD) Blu-ray disc
Capacity 1.44MB 650-880MB 4.7-20GB 23.3-50GB
Transfer Rate 0.06 MB/s 3.5 MB/s 22.6MB/s 36MB/s
Interface IDE IDE/SCSI-2 IDE/SCSI-2 IDE/SCSI-2
3. BLU-RAY DISC KEY CHARACTERISTICS
3.1 Large recording capacity up to 27GB
By adopting a 405nm blue-violet semiconductor laser, with a 0.85NA field lens and a 0.1 mm. optical transmittance protection disc layer structure, it can record up to 27GB video data on a single sided 12cm phase change disc. It can record over 2 hours of digital high definition video and more than 13 hours of standard TV broadcasting (VHS/standard definition picture quality, 3.8Mbps)
3.2 High-speed data transfer rate 36Mbps
It is possible for the Blu-ray Disc to record digital high definition broadcasts or high definition images from a digital video camera while maintaining the original picture quality. In addition, by fully utilizing an optical discâ„¢s random accessing functions, it is possible to easily edit video data captured on a video camera or play back pre-recorded video on the disc while simultaneously recording images being broadcast on TV.
3.3 Easy to use disc cartridge
An easy to use optical disc cartridge protects the optical discâ„¢s recording and playback phase from dust and fingerprints.

3.4 Main Specifications
Recording capacity 23.3GB/25GB/27GB
Laser wavelength 405 nm, (blue-violet laser)
Lens numerical aperture (NA) 0.85
Data transfer rate 36Mbps
Disc diameter 120mm
Disc thickness 1.2mm
Recording format Phase change recording
Tracking format Groove recording
Tracking pitch 0.32um
Shortest pit length 0.160/0.149/0.l38um
Recording phase density 16.8/18.0/1 9.5Gbit/inch2
Video recording format MPEG2 video
Audio recording format AC3, MPEG1, Layer2, etc.
Video and audio multiplexing format MPEG2 transport stream
Cartridge dimension Approximately 129 x 131 x 7mm

4. BLUE LASER
A blue laser is a laser (pronounced LAY-zer) with a shorter wavelength than the red laser used in todayâ„¢s compact disc and laser printer technologies and the ability to store and read two to four times the amount of data. When available in the marketplace, personal computer users may be able to buy a laser printer with a resolution up to 2400 pixels or dots per inch at an affordable price. The same technology in CD and DVD players will provide a dramatic breakthrough in storage capability without an increase in device size.
A laser (an acronym for light amplification by stimulated emission of radiation) is a coherent (meaning all one wavelength, unlike ordinary light which shower on us in many wavelengths) and focused beam of photons or particles of light. The photo are produced as the result of a chemical reaction between special materials and then focused into a concentrated beam in a tube containing reflective mirrors. In the blue laser technology, the special material is gallium nitride. Even a small shortening of wavelength of light can have a dramatic effect in the ability to store and access data. A shorter wavelength allows a single item of data (0 or 1) to be stored in a smaller space.
Red lasers used in todayâ„¢s technologies have wavelengths of over 630 nanometers (or 630 billionths of a meter). The blue laser has a wavelength of 505 nanometers.
Shuji Nakamura, a Japanese researcher working in a small chemical company, Nichia chemical Industries, built the first blue laser diode. However, a number of companies have announced progress in the ability to manufacture blue laser diodes and there are now prototypes of working DVD writers and players. Recently, a standard called Blu-ray has been developed for the manufacture of blue laser optical disc technology.
4.1 Blue ”Violet Laser
SANYO has developed the worldâ„¢s first blue-violet laser diode with a new low-noise (stable) beam structure produced using ion implantation. The stable beam structure boasts lower noise, and current consumption achieving higher performance compared with conventional blue- violet laser diodes. This structure makes SANYOâ„¢s blue-violet laser diode an optimum light source for large-capacity optical disc systems like Blu ray disks.
Main Features
¢ SANYO™s original ion implantation technology has yielded the world™s first blue- violet laser diode with a new stable beam structure that generates a low-noise beam
¢ The stable beam structure produces a vastly improved stable laser beam, which yields the low-noise, low-operating current characteristics that are required in a light source for next-generation large-capacity optical disc systems like advanced DVDs require
¢ The laser diode is easily mass produced because the stable beam structure reduces the number of fabrication steps while the top and bottom electrodes structure reduces chip size
Development Background
Laser diodes are key components in the field of optical data processing devices. SANYOâ„¢s aggressive efforts in this area led to the mass production and sales of AlGaAs (aluminum-gallium-arsenide) infrared and AlGaInP (aluminum-gallium-indium-phosphide) red laser diodes widely used in measuring instruments and a variety of optical data processing devices like CD and DVD optical disc systems.
In recent years, the field of optical disc systems has seen the development of next- generation large-capacity optical disc systems like advanced DVDs that can record more than two hours of digital high-definition images. The blue-violet laser diode made of InGaN (indium gallium-nitride) that is used as a light source for reading signals recorded on the optical discs was the key to developing these systems. Naturally demand for the laser diode is expected to rise sharply as more large-capacity optical disc systems become available and become more widely used.
In order to realize a blue-violet laser diode SANYO has developed original crystal and device fabrication technologies over the years. Now these fundamental technologies have yielded the worldâ„¢s first low-noise beam, blue-violet laser diode with a new stable beam structure that lowered noise and current consumption for higher performance. This development can make large-capacity optical disc systems like advanced DVDs practical.
Features of the new technology
¢ The new stable beam structure made by ion implantation significantly improves laser beam stability and yields the low-noise, low-operating current characteristics that the optical disc system requires.
¢ The laser diode is easily mass-produced because the newly developed stable beam structure reduces the number of fabrication steps while the top and bottom electrodes structure reduces chip size.
Other Features
¢ Fundamental traverse mode
The fundamental traverse mode generates a single stable beam which means the beam can be focused into a tiny spot using a simple optical system.
¢ Package
The package is compact at just 5.6 mm in diameter.
¢ Advanced DVDs as well as for Polarity
A positive (+) or negative (-) power supply can be selected
¢ Built-in photodiode for monitoring optical output
A photodiode is installed to monitor optical output
¢ Applications
The new laser diode is suitable for the next-generation large-capacity optical disc systems like and many types of measuring instruments.
Terminology
¢ Blue-violet laser diode
This is the light source used to read signals (pits) on discs in next-generation large-capacity optical disc systems. There is no way the size of beams from the infrared and red laser diodes now used in CDs and DVDs can be reduced to the size of a pit recorded on these, discs in c optical systems. The shorter wavelength of the blue-violet laser diode however allows the beam to be focused into a reduced spot, and therefore is the key to next-generation large-capacity optical disc systems.
¢ Stable beam structure
The newly developed stable beam structure was produced using ion implantation. With mode c9ntrol Ëœof the laser beam and current confinement, the implanted layer significantly improves laser beam stability and yields the low-noise, low-operating current characteristics that an optical disc system requires
¢ Ion implantation
This technology uses a strong electric field to force ionized atoms into a semiconductor. It is mainly used in Si LSI production for doping impurities in semiconductors. The amount and depth of the atoms implanted into the semiconductor can be precisely Ëœcontrolled with consistent reproducibility
¢ Fundamental traverse mode
This refers to a mode where distribution of light intensity in a laser beam forms a single peak.

5. ACCESSING THE DISC
5.1 Phase change recording

Fig.5. 1.1 Phase change recording mechanism
The basic concept in phase change memories starts with the use of a material which can exist in two separate structural states in a stable fashion. An energy barrier must be overcome before the structural state can be changed, thereby providing the stability of the two structures. Energy can be supplied to the material in various ways, including exposure to intense laser beams and application of a current pulse. Laser exposure is used for recording and erasing in the case of an optical memory. If the energy applied exceeds a threshold value, the material will be excited to a high mobility state, in which it becomes possible to rapidly rearrange bond lengths and angles by slight movement of the individual atoms. In lone pair materials divalently bonded this may simply be shifting of non-bonding or weakly bonding lone pairs to make new connections. In a material such as germanium compositions can be selected in which these minute changes in bonding position of the atoms can cause profound changes in the physical properties of the material, including its optical absorptivity and reflectivity.
The importance of the composition lies in the selection of a material composition which can form a crystalline structure without phase segregation. Selection of an appropriate composition and inducing high mobility state during laser exposure are the underlying principles in direct- overwrite phase change erasable optical recording media. Our early work established that materials in the Ge-Sb-Te ternary are capable of rapid transition between the two states, and our later work in the investigation of the relationship between the crystalline properties and the performance of various materials applied as optical recording media clarifies the reasons for the importance of the composition (7,8). Direct-overwrite is simply the process of recording new information in a location which had been previously recorded without first erasing the old information. Two major material properties are required to provide this capability, First, the speed of the transition must be very fast.
The structure of the current phase change erasable materials can easily be transformed in either direction by pulses of 50 nanosecond duration. Second, the energy delivered by the laser beam, at both the amorphizing or crystallizing power levels must be equally absorbed by the phase change material when it is in either structural state. The indexes of refraction and the absorption coefficients of the phase change material in its two structural states inherently provide this capability, and appropriate design of the optical stack used to form the device provides the final tuning. The large differences in optical constants between the two structures leads to a major advantage of phase change optical disks in that the read contrast is very high. The two structures, have very different reflectivities, an attribute which leads to manufacturability with relaxed layer thickness tolerances. Contrasted to the competing magneto-optical disks, which have a small read contrast, and further, have a read signal which must be differentiated by a more complex evaluation of polarization, phase change disks can be manufactured more economically.
The device structures used in products produced by our licensees are sophisticated designs which apply principles we established for the protection of the phase change alloy from atmospheric contamination and chemical interaction with the protective layer itself with enhanced optical coupling and careful handling of the thermal considerations involved in the interaction of the memory alloy with the laser light. High yield consistent manufacturing is of course a major consideration in the production of any product, and our licensees have done an outstanding job of developing a well controlled process with good yield. Use of materials which have the same composition in the amorphous and crystalline phases also provides long life. Since no diffusion is involved in the phase change process, no phase segregation occurs and life is only limited by the integrity of the Substrate. A plastic such as polycarbonate will begin to show degradation in its surface smoothness after 100,000 re-writes, and will contribute to a background noise level which will limit cycle life to about one million cycles. Disks made with advanced plastics or glass, or those which use dielectric layers more effective in stabilizing the plastic surface will have a much longer cycle life.
Once the substrate material has been formatted, the roll is placed in a vacuum chamber and the layers of the phase change and encapsulation materials are coated, again in a continuous process, The roll of coated media is then laminated to a somewhat thicker polycarbonate film, which serves as the Cover slip to provide for dust and scratch protection required in a durable product. The final manufacturing step is simple stamping of the individual formatted disks from the web. The great advantage of this production technique is its low cost. Not only does the continuous process red manufacturing costs, but the selection of disk diameter allows linear control of the cost per disk.
5.2 Groove Recording
The physical surface of the disc consists of lands and grooves. In Blu-ray discs, data is written only onto the grooves. In phase change discs the groove depth is designed to be ?/6n, where ? is the pickup user wavelength and n is the optical index of the substrate. This reduces cross talk between the lands and the grooves, and allows conventional tracking signal schemes to be used with narrow track pitches.

Fig.5.2. I groove recording
The figure above shows a typical Blu-ray structure. A Blu-ray disc holds 23.3/ 27 GB per side. This high recording density was achieved through the use of mark edge recording, along with the use of groove recording, which is effective for use with narrow track pitches recording, in which data is recorded only within the tracking grooves. There is a limit to how much track pitch can be reduced as a means of increasing recording density, as narrow track pitch tends to weaken the tracking servo signal and increase crosstalk The solution is groove recording In phase change discs the groove depth is designed to be la/6n, where is the pickup laser wavelength and n is the optical, index of the substrate. This reduces crosstalk between the lands and the grooves, and allows conventional tracking signal schemes to be used with narrow track pitches. The reduction in crosstalk with the land and groove method is a result of the fact that the reduction in reflected light due to interference with a neighboring track when in crystalline state is approximately the same as decrease in reflectivity when in amorphous state at a particular depth. That depth is about lambda/6n, which is about 36 nm for a 405nm laser wavelength. Blu -Ray uses this kind of land and groove recording, with a track pitch of 0.32 ?m.

6. APPLICATIONS
6.1 Ultra Density Optical (UDO)
UDO is the next generation of 5.25 professional optical storage technology. It is a convergent technology that delivers the performance of 5.25 MO, the longevity 12-inch WORM, and the cost effectiveness of DVD. It utilizes violet laser and phase change media recording technology to provide a quantum leap in data storage densities. First generation UDO products will be 30GB capacity and are scheduled to ship in August 2003. Future generations will increase capacity to 60GB and 120GB and will provide full backward read compatibility. Both WORM and rewritable media will be available and the cartridgeâ„¢ will be physically identical to 5.25 MO to maintain library compatibility. Target markets include archiving, document imaging, call centers, e-mail archiving, GIS, medical, telecom, banking, insurance, legal and government.
UDO is the application of Blu-ray consumer recording technology to the professional optical storage market. Blu-ray is the proposed successor to DVD and uses phase change recording technology to provide the storage capacity to record aâ„¢ full-length HDTV video. The use of violet lasers and high NA optics dramatically increases data storage densities and necessitates a new type of disk construction with a 0.1mm cover layer to protect the data surface. As with existing MO technology, UDO uses non contact recording to provide robust and reliable performance.

6.2 Digital Video Recording
The Bin-ray Disc using Ëœblue-violet laser achieves over 2-hour digital high definition video recording on a 12cm diameter CD/DVD size phase change optical disc.
The Blu-ray Disc enables the recording, rewriting and play back of up to 27 gigabytes (GB) of data on a single sided single layer 12cm CD/DVI) size disc using a 405nm blue-violet laser. By employing a short wavelength blue violet laser, the Blu Disc successfully minimizes its beam spot size by makingâ„¢ the numerical aperture (NA) on a field lens that converges the laser 0.85. In addition, by using a disc structure with a 0.1mm optical transmittance protection layer, the Blu-ray Disc diminishes aberration caused by disc tilt. This also allows for disc better readout and an increased recording density. The Blu-ray Discâ„¢s tracking pitch is reduced to 0.32um, almost half of that of a regular DVD, achieving up to 27 GB high-density recording on a single sided disc.
Because the Blu-ray Disc utilizes global standard MPEG-2 Transport. Stream compression technology highly compatible with digital broadcasting for video recording, a wide range of content can be rec9rded. It is possible for the Blu-ray Disc to record digital high definition broadcasting while maintaining high quality and other data simultaneously with video data if they are received together. In addition, the adoption of a unique ID written on a Blu-ray Disc realizes high quality copyright protection functions.
The Blu-ray Disc is a technology platform that can store sound and video while maintaining high quality and also access the stored content in an easy-to-use way. This will be important in the coming broadband. era as content distribution becomes increasingly diversified. The nine companies involved in, the announcement will respectively develop products that take full advantage of Blu-ray Discâ„¢s large capacity and high-speed data transfer rate. They are also aiming to further enhance the appeal of the new format through developing a larger capacity, such as over 30GB on a single sided single layer disc and over 50GB on a single sided double layer disc. Adoption of the Blu-ray Disc in a variety of applications including PC data storage and high definition video software is being considered
7. FUTURE DEVELOPMENT
¢ Large capacity:- sided double layer for 50 (113 by using t multilayer technology.
¢ High Speed Transfer Rate:-To realize higher recording performance
¢ Media family:- ROM,R( Write Once)
¢ Application:- Adoption in a variety of applications including PC data storage and high definition video software.

8. CONCLUSION
8.1 The Blu-ray Impact
Blu-ray is expected to challenge DVDâ„¢s run as the fastest selling consumer-electronics item in history. If that happens, the impact would be too big for the major players to discount. For example, the number of films sold on DVD more than doubled last year to over 37 million. In addition, almost 2.4. million DVD players were bought in the past year. As Blu-ray is not compatible with DVD, its success could upset the applecart of many players. If the new format turns out to be much popular, the demand for DVD players could come down drastically. Not withstanding the challenge to DVD makers, the new format is seen as a big step in the quest for systems offering higher data storage. It is expected to open up new opportunities for broadcasting industry. Recording of high-definition television video-an application in which more than 10GB of storage space is filled up with just one hour of video-will get a major boost. Conversely, the format could take advantage of the spread of high-definition television. As Blu-ray Disc uses MPEG-2 Transport Stream compression technology, recording for digital broadcasting would become easier Its adoption will grow in the broadband era as it offers a technology platform to manage stored content. But the real action will begin when the companies involved develop products that take full advantage of Blu-ray Discâ„¢s large capacity and high-speed data transfer rate. As that happens, Blu-ray will move beyond being a recording tool to a variety of applications. Adoption of Blu-ray Disc in PC data storage is already being considered.

8.2 Not Beaming As Yet
However, it will be many years before the Blue-ray finds such high-demand applications. Blu-ray compatible systems arc likely to hi the market only in 2003. The nine companies involved have just begun work on the hardware. Licensing for technology to play the discs will start within the next few months. Cost will also play a crucial role in the development of commercial systems. A sample blue-laser diode currently costs .around $1,000, making consumer products based on it unrealistic. I however, the price of a blue-laser diode is expected to tumble once Nichia Corp”the major source for blue lasers”begins commercial production. The biggest question that is plaguing the industry is whether current DVD discs will be compatible with the new machines. Wary of alienating DVD fins, the companies are looking for ways to make the new products compatible with DVDs.
8.3 A Uniform Picture
Buoyed by the expected price fall, many electronics companiesâ„¢ began to work on blue-laser based development systems in the last few months and Blu-ray is a direct outcome of these efforts. The similarity of the work being done prompted the companies to look for a standard format that would wipe out the differences between those made by individual companies. The companies had learnt the need for a standard format the hard way a la DVDs.

8.4 The Jarring Image
However, it appears that not everyone has learnt from the DVD episode. As Blu-ray moves towards commercialization, it could ignite a new format battle Among the Blu-ray group are six of the 10 companies that worked, on developing the DVD format. Four of DVDâ„¢s main backers-Mitsubishi, AOL Time Warner, Victor of Japan and Toshiba Corp-- are staying away from the Blu-ray consortium. Toshibaâ„¢s absence is the most conspicuous. The company has publicly stated that it intends to propose its prototype blue-laser optical-disc format. Consequently, its absence raises the possibility that a format battle may be about to begin again. Lending credence to this theory is the fact that the nine companies, which are also on the steering committee of the DVD Forum, are conducting the Blu-ray work outside of the Forum Much like the DVD story, the battle isnâ„¢t going to end soon. But a compromise formula can be worked out Already, there is evidence of concessions to get major players around a single format The Blu-ray groupâ„¢s announcementâ„¢ that discs are expected to be available in three different sizes, is one such example. Some companies want to keep the price of discs low by using cheaper materials that will be able to hold slightly less data
8.5 Future Perfect
Despite the impending tug-of war, the industry is excited, about the future prospects, of this technological innovation The industry is of the view that Blu-may has the potential to replicate, if not better, the DVD success story. The expected upswing in high-definition television adoption and broadband implementation could act as the catalyst. Aware that the recession in economies across the globe could come in the way of high-definition television broadband penetration, major players are exploring the ways In make Blu-ray compatible with DVDs. Cost can dampen the sales in the first year. Owing to th patent and the technology involved, Blu-ray is likely to cost more than DVDs. But sooner than later, it will move towards commodity pricing. Once that happens, Blu-ray holds the promise to steal a march over its immediate predecessor.

9. BIBLIOGRAPHY
World Wide Web
¢ whatis.com
¢ bluraytalk.com
¢ computerworld.com
¢ dvdeurope2002.com
¢ bluray.org
Documents
¢ A History Of the Phase Change Technology Stanford Ovshinsky, president of Energy Conversion Devices
¢ Removable Media Storage Devices Tom Pratt and Chris Steenbergen, Storage Technology


ACKNOWLEDGEMENT
I express my sincere gratitude to Dr. Agnisarman Namboodiri, Head of Department of Information Technology and Computer Science, for his guidance and support to shape this paper in a systematic way.
I am also greatly indebted to Mr. Saheer H. and Ms. S.S. Deepa, Department of IT for their valuable suggestions in the preparation of the paper.
In addition I would like to thank all staff members of IT department and all my friends of S7 IT for their suggestions and constrictive criticism.
Amjad Anam

CONTENTS
1. Introduction ¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦. 01
2. Evolution of Optical Removable Media Storage Devices¦¦... 02
2.1 Optical Storage ¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦ 02
2.1.1 CD-ROM ¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦ 03
2:1.2 CD-R¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦ 04
2.1.3CD-RW ¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦ 05
2.1.4DVD¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦. 06
2.1.4.1 Single Layers and Dual Layers¦¦¦¦. 06
2.1.4.2 DVD Data Storage Versions¦¦¦¦¦. 07
2.1.4.2.1 DVD-R ¦¦¦¦¦¦¦¦¦... 07
2.1.4.2.2.DVD-RAM ¦¦¦¦¦¦¦¦. 08
2.1.4.2.3DVD-RW ¦¦¦¦¦¦¦¦¦ 08
2.2 DVDvs.CD¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦.. 09
3. Blu-ray Disc Key Characteristics¦¦¦¦¦¦¦¦¦¦¦¦ 10
3.1 Large recording capacity up to 27GB ¦¦¦¦¦¦¦¦ 10
3.2 High-speed data transfer rate 36Mbps¦¦¦¦¦¦¦¦. 10
3.3 Easy to use disc cartridge ¦¦¦¦¦¦¦¦¦¦¦¦¦ 10
3.4 Main Specifications¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦. 11
4. Blue Laser ¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦. 12
4.1 Blue-Violet laser¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦. 13
5. Accessing the Disc ¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦... 17
5.1 Phase change recording¦¦¦¦¦¦¦¦¦¦¦¦¦.. 17
5.2 Groove Recording¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦... 20
6. Applications¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦.. 22
6.1 Ultra Density Optical (UDO)¦¦¦¦¦¦¦¦¦¦¦.. 22
6.2 Digital Video Recording¦¦¦¦¦¦¦¦¦¦¦¦¦. 23
7. Future development ¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦. 24
8. Conclusion ¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦... 25
8.1 The Blu-ray Impact ¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦ 25
8.2 Not Beaming As Yet¦¦¦¦¦¦¦¦¦¦¦¦¦¦.. 26
8.3 A Uniform Picture¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦. 26
8.4 The Jarring Image¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦. 27
8.5 Future Perfect ¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦.. 27
9. Bibliography ¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦.. 29
Use Search at http://topicideas.net/search.php wisely To Get Information About Project Topic and Seminar ideas with report/source code along pdf and ppt presenaion
Reply
computer science technology
Active In SP
**

Posts: 740
Joined: Jan 2010
#2
23-01-2010, 01:58 AM


.doc   Blu-ray.doc (Size: 89.5 KB / Downloads: 195)
Use Search at http://topicideas.net/search.php wisely To Get Information About Project Topic and Seminar ideas with report/source code along pdf and ppt presenaion
Reply
computer science technology
Active In SP
**

Posts: 740
Joined: Jan 2010
#3
23-01-2010, 08:48 PM


.ppt   Blu-ray-disc.ppt (Size: 628 KB / Downloads: 508)
.pdf   Blu-Ray Disc full report.pdf (Size: 687.7 KB / Downloads: 585)

Seminar Report On Blu-Ray Disc
ABSTRACT
Blu-ray, also known as Blu-ray Disc (BD) is the name of a next-generation optical disc format jointly
developed by the Blu-ray Disc Association (BDA), a group of leading consumer electronics and PC companies
(including Apple, Dell, Hitachi, HP, JVC, LG, Mitsubishi, Panasonic, Pioneer, Philips, Samsung, Sharp, Sony, TDK
and Thomson). The format was developed to enable recording, rewriting and playback of high-definition video
HD), as well as storing large amounts of data. The Blu-ray Disc using blue-violet laser achieves over 2-hour digital
high definition video recording on a 12cm diameter CD/DVD size phase change optical disc.
The Blu-ray Disc enables the recording, rewriting and play back of up to 25 gigabytes (GB) of data on a
single sided single layer 12cm CD/DVD size disc using a 405nm blue-violet laser. By employing a short
wavelength blue violet laser, the Blu-ray Disc successfully minimizes its beam spot size by making the
numerical aperture (NA) on a field lens that converges the laser 0.85. This also allows for disc better readout
and an increased recording density. The Blu-ray Disc's tracking pitch is reduced to 0.32um, almost half of
that of a regular DVD, achieving up to 25 GB high-density recording on a single sided disc.
Because the Blu-ray Disc utilizes global standard "MPEG-2 Transport Stream" compression
technology highly compatible with digital broadcasting for video recording, a wide range of content can be
recorded. It is possible for the Blu-ray Disc to record digital high definition broadcasting while maintaining
high quality and other data simultaneously with video data if they are received together. In addition, the
adoption of a unique ID written on a Blu-ray Disc realizes high quality copyright protection functions.
The Blu-ray Disc is a technology platform that can store sound and video while maintaining high
quality and also access the stored content in an easy-to-use way. This will be important in the coming
broadband era as content distribution becomes increasingly diversified.
Submitted by
Ratheesh K
In the partial fulfillment of requirements in degree of
Master of Technology (M-Tech)
in
CHAPTER -1
INTRODUCTION TO BLU RAY DISC
1.1 What is a Blu-ray disc
Blu-ray disc is a next-generation optical disc format jointly developed by a group of
leading consumer electronics and PC companies called the Blu-ray Disc Association (BDA),
which succeeds the Blu-ray Disc Founders (BDF). Because it uses blue lasers, which have
shorter wavelengths than traditional red lasers, it can store substantially more data in the same
amount of physical space as previous technologies such as DVD and CD.
A current, single-sided, standard DVD can hold 4.7 GB (gigabytes) of
information. That's about the size of an average two-hour, standard-definition movie with a few
extra features. But a high-definition movie, which has a much clearer image, takes up about five
times more bandwidth and therefore requires a disc with about five times more storage. As TV sets
and movie studios make the move to high definition, consumers are going to need playback
systems with a lot more storage capacity.
The advantage to Blu-ray is the sheer amount of information it can hold :
¢ A single-layer Blu-ray disc, which is roughly the same size as a DVD, can hold up to 27 GB
of data ” that's more than two hours of high-definition video or about 13 hours of standard
video.
¢ A double-layer Blu-ray disc can store up to 54 GB, enough to hold about 4.5 hours of
high-definition video or more than 20 hours of standard video. And there are even plans
in the works to develop a disc with twice that amount of storage.
1.2 Why the name Blu-ray
The name Blu-ray is derived from the underlying technology, which utilizes a blue-violet laser to read and
write data. The name is a combination of "Blue" and optical ray "Ray". According to the Blu-ray Disc
Association, the spelling of "Blu-ray" is not a mistake. The character "e" is intentionally left out because a
daily-used term cant be registered as a trademark.
1.3 Who developed Blu-ray
Seminar report on Blu-Ray Disc
Department of Computer Science,CUSAT 5
The Blu-ray Disc format was developed by the Blu-ray Disc Association 1BDA),
a group of leading consumer electronics and PC companies with more than 130 members from all over
the world. The Board of Directors currently consists of:
Apple Computer
Inc. Dell Inc.
Helewlett Packard Company
Hitachi Ltd.
LG Electronics Inc.
Matsushita Electric Industrial Co. Ltd.
Mitsubishi Electric Corporation
Pioneer Corporation
Royal-Philips
Electronics
Samsung Electronics Co. Ltd
Sharp Corporation
Sony Corporation
TDK
Corporation
Thomson
Multimedia Walt
Disney Pictures
CHAPTER “2
Seminar report on Blu-Ray Disc
Department of Computer Science,CUSAT 6
BLU-RAY TECHNOLOGY
2.1 INTRODUCTION TO BLU-RAY TECHNOLOGY
The Objective of Blu-ray The standards for 12-cm optical discs, CDs, DVDs, and
Blu-ray rewritable discs (BD-RE Standard) were established in 1982, 1996, and 2002,
respectively. The recording capacity required by applications was the important issue when
these standards were decided (See fig). The requirement for CDs was 74 minutes of recording 2-
channel audio signals and a capacity of about 800 MB. For DVDs, the requirement as a video
disc was the recording of a movie with a length of two hours and fifteen minutes using the SD
(Standard Definition) with MPEG-2 compression. The capacity was determined to be 4.7 GB
considering the balance with image quality.
In the case of the Blu-ray *1) Disc, abbreviated as BD hereafter, a recording of an
HDTV digital broadcast greater than two hours is needed since the BS digital broadcast started
in 2000 and terrestrial digital broadcast has begun in 2003. It was a big motivation for us to
realize the recorder using the optical disc. In a DVD recorder, received and decoded video
signals are compressed by an MPEG encoder and then recorded on the disc.
To record in the same fashion for an HDTV broadcast, an HDTV MPEG-2 encoder
is required. However, such a device for home use has not yet been produced. In the case of BS
digital broadcasts, signals are sent as a program stream at a fixed rate, which is 24 Mbps for one
HDTV program. In the program stream of BS digital broadcast there is a case that the additional
data stream is multiplexed, and it is desirable to record and read the data as is. Two hours of
recording requires a recording capacity of 22 GB or more. This capacity is about 5 times that of
DVDs, which cannot achieve this capacity by merely increasing their recording density.
Seminar report on Blu-Ray Disc
Department of Computer Science,CUSAT 7
To obtain this capacity we have developed a number of techniques such as:
employing a blue-violet laser, increasing the numerical aperture of objective lens, making the
optical beam passing substrate thin, 0.1 mm, and evenly thick, using an aberration compensation
method of pickup adapted to the substrate thickness and dual layer discs, improving the
modulation method, enhancing the ability of the error correction circuit without sacrificing the
efficiency, employing the Viterbi decoding method for reading signals and improving the S/N
ratio and the inter symbol interference, using the on-groove recording and highly reliable
wobbling address system, developing high speed recording phase change media, etc. In addition,
the convenient functions of a recording device have also been realized in the application
formats.
These techniques are described in this paper. Furthermore, the key concepts of the
Blu-ray standard such as the reason for employing 0.1 mm thick transparent layer and a dual
layer recording disc will be described in each dedicated chapter. Following the rewritable
system, the planning of a read-only system and write-once system has already started. In
addition to high picture quality, the introduction of core and new functions is indispensable for
the spread of the next generation package media. For example, during the switch from VHS to
DVD, digital recording and interactive functions were newly introduced. Consequently, it is
anticipated that the specifications of BD-ROM will provide a high performance interactiveness
and a connection to broadband services, reflecting the demands of the movie industry (Fig).
Seminar report on Blu-Ray Disc
Department of Computer Science,CUSAT 8
2.2OPTIMIZATION OF THE COVER LAYER THICKNESS
Roots of a 1.2 mm substrate existed in the video disc. One of advantages of laser discs
has been that they are hardly affected by dirt or dust on the disc surface since information is
recorded and read through a cover layer. The first commercial optical disc, which was the
videodisc called VLP or Laser Disc, used a 1.2 mm thick transparent substrate, through which
information was read. This thickness was determined from conditions such as: - Deterioration of
the S/N ratio due to surface contamination was suppressed to a minimum since it used analog
recording,
- A disc of 30 cm in diameter can be molded,
- The disc has sufficient mechanical strength,
- The disc is as thin as possible while satisfying the flatness and optical uniformity.
The last condition is because the thinner the cover layer, the more easily the performance of the
objective lens to converge the laser beam can be improved. This convergence performance of
the objective lens is expressed by what we call NA (Numerical Aperture), and the diameter of a
converging light is inversely proportional to NA (Fig. 1.2.1). Thus NA is required to be as large
Seminar report on Blu-Ray Disc
Department of Computer Science,CUSAT 9
as possible. However, when the optical axis of the objective lens shift from the perpendicular to
the disc surface, a deterioration of the convergence performance (aberration) occurs and its
amount grows proportionally to the cube of NA. Since we cannot avoid discs from tilting to
some extent from the optical axis of the objective lens due to the bending of discs or inclination
of the mounting, and it has prevented the value of NA from increasing.
NA- Numerical Aperture is defined as sin(_). Where _ is half angle of converging
light converged by an objective lens. Around 80% of light energy is converged in
an area with diameter of _ / NA
On the other hand, an aberration caused by a disc inclination is proportional to the thickness of
the cover layer. This aberration was originate in a of the refraction angle error at the cover layer
interface resulting from the disc inclination. Further, the amount of blur in the beam spot due to
the refraction angle error is proportional to the distance between the disc surface and the focal
point as shown below.
Seminar report on Blu-Ray Disc
Department of Computer Science,CUSAT 10
When the disc tilts refraction angle error, which is deviation from ideal angle to form an ideal
light spot, occurs at the disc surface. This refraction angle error causes aberration at the focal
point. Then the aberration is in proportion to the distance between disc surface and the focal
point, i.e., the aberration is in proportion to thickness of cover layer.
2.3 LASER TECHNOLOGY
The technology utilizes a "blue" (actually blue-violet) laser diode operating at a
wavelength of 405 nm to read and write data. Conventional DVDs and CDs use red and infrared
lasers at 650 nm and 780 nm respectively.
As a color comparison, the visible color of a powered fluorescent black light tube is
dominated by mercury's bluish violet emissions at 435.8 nm. The blue-violet laser diodes used in
Blu-ray Disc drives operate at 405 nm, which is noticeably more violet (closer to the violet end of
the spectrum) than the visible light from a black light. A side effect of the very short wavelength is
that it causes many materials to fluoresce, and the raw beam does appear as whitish-blue if shone on
a white fluorescent surface (such as a piece of paper). While future disc technologies may use
fluorescent media, Blu-ray Disc systems operate in the same manner as D and DVD systems and
do not make use of fluorescence effects to read out their data.
The blue-violet laser has a shorter wavelength than CD or DVD systems, and this shrinking
makes it possible to store more information on a 12 cm (CD/DVD size) disc. The minimum "spot
size" that a laser can be focused is limited by diffraction, and depends on the wavelength of the
Seminar report on Blu-Ray Disc
Department of Computer Science,CUSAT 11
light and the numerical aperture (NA) of the lens used to focus it. By decreasing the wavelength
(moving toward the violet end of the spectrum), using a higher NA (higher quality) dual-lens
system, and making the disk thinner (to avoid unwanted optical effects), the laser beam can be
focused much tighter at the disk surface. This produces a smaller spot on the disc, and therefore
allows more information to be physically contained in the same area.In addition to optical
movements, Blu-ray Discs feature improvements in data encoding, closer track and pit spacing,
allowing for even more data to be packed in.
2.3.1 DIODE
A laser diode is a laser where the active medium is a semiconductor p-n junction
similar to that found in a light-emitting diode. Laser diodes are sometimes referred to (somewhat
redundantly) as injection laser diodes or by the acronyms LD or ILD.
(a) PRINCIPAL OF OPERATION
When a diode is forward biased, holes from the p-region are injected into the
n-region, and electrons from the n-region are injected into the p-region. If electrons and holes are
present in the same region, they may radiatively recombine”that is, the electron "falls into" he hole
and emits a photon with the energy of the band gap . This is called spontaneous emission, and is the
main source of light in a light-emitting diode.
Under suitable conditions, the electron and the hole may coexist in the same
area for quite some time (on the order of microseconds) before they recombine. If a photon f exactly
the right frequency happens along within this time period, recombination may be stimulated by
the photon. This causes another photon of the same frequency to be emitted, with exactly the same
direction, polarization and phase as the first photon.
In a laser diode, the semiconductor crystal is fashioned into a shape
somewhat like a piece of paper”very thin in one direction and rectangular in the other two. The of
the crystal is n-doped, and the bottom is p-doped, resulting in a large, flat p-n junction .The two
ends of the crystal are cleaved so as to form a perfectly smooth, parallel edges; two reflective
parallel edges are called a Fabry-Perot cavity. Photons emitted in precisely the right direction
will be reflected several times from each end face before they are emitted. Each time they pass
through the cavity, the light is amplified by stimulated emission. Hence, if there is more
amplification than loss, the diode begins to "lase"
(b) TYPES OF LASER IODES
Seminar report on Blu-Ray Disc
Department of Computer Science,CUSAT 12
(i) Double heterostructure lasers
In these devices, a layer of low band gap material is sandwiched between two
high band gap layers. One commonly used pair of materials is GaAs with AlGaAs. Each of the junctions
between different band gap materials is called a heterostructure, hence the name "double heterostructure
laser" or DH laser. The kind of laser diode described in the first part of the article is referred to as a
"homojunction" laser, for contrast with these more popular devices.
The advantage of a DH laser is that the region where free electrons and holes
exist simultaneously”the "active" region”is confined to the thin middle layer. This means that
many more of the electron-hole pairs can contribute to amplification”not so many are left out in the
poorly amplifying periphery. In addition, light is reflected from the heterojunction; hence, the
light is confined to the region where the amplification takes place.
ii) Quantum well lasers
If the middle layer is made thin enough, it starts acting like a quantum well.
This means that in the vertical direction, electron energy is quantized. The difference between
quantum well energy levels can be used for the laser action instead of the band gap. This is very useful
since the wavelength of light emitted can be tuned simply by altering the thickness of the layer. The
efficiency of a quantum well laser is greater than that of a bulk laser due to a tailoring of the
distribution of electrons and holes that are involved in the stimulated emission (light producing)
process.
The problem with these devices is that the thin layer is simply too small to effectively
confine the light. To compensate, another two layers are added on, outside the first three. These layers
have a lower refractive index than the center layers, and hence confine the light effectively. Such a
design is called a separate confinement heterostructure (SCH) laser diode. Almost all commercial laser
diodes since the 1990s have been SCH quantum well diodes
2.4 HARD-COATING TECHNOLOGY
The entry of TDK to the BDF (as it was then), announced on 19 March 2004,was
accompanied by a number of indications that could significantly improve the outlook for Blu-ray. TDK
Seminar report on Blu-Ray Disc
Department of Computer Science,CUSAT 13
is to introduce hard-coating technologies that would enable bare disk (caddyless) handling, along
with higher-speed recording heads and multi-layer recording technology (to increase storage
densities).TDK's hard coating technique would give BDs scratch resistance and allow them to be cleaned of
fingerprints with only a tissue, a procedure that would leave scratches on current CDs and DVDs.
2.5 CONTRIBUTION OF HIGH NA TO THE LARGE CAPACITY
Like the BD-RE system, the pick up head for BD-ROM uses a high numerical aperture
(NA) lens of 0.85 and a 405 nm blue laser. In early BD-RE systems the high NA was realized by
using 2 lenses in combination. Today many single lenses with working distance larger than
0.5mm have been developed, and even lenses which can be used in DVD/BD compatible pick
ups and CD/DVD/BD compatible pick ups have been developed.
Seminar report on Blu-Ray Disc
Department of Computer Science,CUSAT 14
Fig: High capacity contribution
Figure shows that the high NA lens increases the areal density by 2 times while the blue
laser contributes an additional factor of 2.6 times compared to the areal density of DVD. In total,
the Blu-ray spot size is less than 1/5 that of DVD, resulting in more than 5 times the capacity of
DVD. Figure2-3 shows the optical beam degradation due to the disc tilt. This degradation is
proportional to NA3 and the thickness of the cover layer. We selected 0.1 mm as the thickness
of the cover layer, achieving more than +- 1.60 deg for the radial tilt margin for BD-ROM,
which is similar to that of DVD-ROM.
Seminar report on Blu-Ray Disc
Department of Computer Science,CUSAT 15
Figure shows that the high NA lens increases the areal density by 2 times while the blue
laser contributes an additional factor of 2.6 times compared to the areal density of DVD. In total,
the Blu-ray spot size is less than 1/5 that of DVD, resulting in more than 5 times the capacity of
DVD. Figure2-3 shows the optical beam degradation due to the disc tilt. This degradation is
proportional to NA3 and the thickness of the cover layer. We selected 0.1 mm as the thickness
of the cover layer, achieving more than +- 1.60 deg for the radial tilt margin for BD-ROM,
which is similar to that of DVD-ROM.
2.6 DISC STRUCTURE
Configuration of SL and DL Discs
Figure shows the outline of a Single Layer BD Read-Only disc and Figure shows the
outline of a Dual Layer BD Read-Only disc. To improve scratch resistance, the cover layer can
optionally be protected with an additional hard coat layer. One of the features that differentiate
Blu-ray Disc from DVD recording systems is the position of the recording layer within the disc.
Seminar report on Blu-Ray Disc
Department of Computer Science,CUSAT 16
For DVD, the recording layer is sandwiched between two 0.6-mm thick layers of plastic - typically
polycarbonate.
The purpose of this is to shift surface scratches, fingerprints and dust particles to a position
in the optical pathway where they have negligible effect - i.e. well away from the point of focus of
the laser. However, burying the recording layer 0.6 mm below the surface of the disc also has
disadvantages.
Due to the injection molding process used to produce them, disc substrates suffer from
stress-induced birefringence, which means that they split the single incident laser light into two
separate beams. If this splitting is excessive, the drive cannot read data reliably from the disc.
Consequently, the injection molding process has always been a very critical part of CD and
DVD production. Another critical manufacturing tolerance, particularly for DVDs, is the flatness
of the disc, because the laser beam becomes distorted if the disc surface is not perpendicular to
the beam axis - a condition referred to as disc tilt. This distortion increases as the thickness of
the cover layer increases and also increases for higher numericalTo overcome these
disadvantages, the recording layer in a Blu-ray Disc sits on the surface of a 1.1-mm thick plastic
substrate, protected by a 0.1-mm thick cover layer.
With the substrate material no longer in the optical pathway, birefringence problems are
eliminated. In addition, the closer proximity of the recording layer to the drive's objective lens reduces
disc tilt sensitivity. This only leaves the problem of surface scratching and fingerprints, which can be
prevented by applying a specifically
Seminar report on Blu-Ray Disc
Department of Computer Science,CUSAT 17
Single “Layer Disc
Dual Layer Disc
Figure shows the outline of a Dual Layer BD Read-Only disc. To improve scratch
resistance, the cover layer can optionally be protected with an additional hard coat layer. The
different layers are shown. A spacing layer is used to separate the two information discs.Also
The different transmission stack are shown
Seminar report on Blu-Ray Disc
Department of Computer Science,CUSAT 18
CHAPTER “3
SPECIFICATION OF BLU-RAY
3.1 TECHNICAL DETAILS
The table below shows the technical specification of Blu-Ray
Recording capacity:
23.3GB/25GB/27GB
Laser wavelength:
405nm (blue-violet laser)
Seminar report on Blu-Ray Disc
Department of Computer Science,CUSAT 19
Lens numerical aperture
(NA):
0.85
Data transfer rate:
36Mbps
Disc diameter:
120mm
Disc thickness:
1 .2mm (optical transmittance protection
layer: 0.1 mm)
Recording format:
Phase change recording
Tracking format:
Groove recording
Tracking pitch:
0.32um
Shortest pit length:
0.160/0.149/0.138um
Recording phase density:
16.8/1 8.0/1 9.5Gbit/inch2
Video recording format
MPEG2 video
Audio recording format:
AC3, MPEG1, Layer2, etc.
Video and audio
multiplexing format:
MPEG2 transport stream
Cartridge dimension:
Approximately 129 x 131 x 7mm
.
3.2 FORMATS
Unlike DVDs and CDs, which started with read-only formats and only later added recordable and
re-writable formats, Blu-ray is initially designed in several different formats:
¢ BD-ROM (read-only) - for pre-recorded content
Seminar report on Blu-Ray Disc
Department of Computer Science,CUSAT 20
¢ BD-R (recordable) - for PC data storage
¢ BD-RW (rewritable) - for PC data storage
¢ BD-RE (rewritable) - for HDTV recording
3.3DATA RATE
For high-definition movies a much higher data rate is needed than for standard
definition. With the BD formatâ„¢s choices for both NA and wavelength we have been able to
realize a format with 5X higher data rate while only doubling the rotation rate of DVD-ROM
discs. The following numbers offer a comparison: Data bit length: 111.75 nm (25GB) (267
nm for DVD) Linear velocity: 7.367 m/s (Movie application) (3.49 m/s for DVD). User data
transfer rate: 53.948 Mbit/s (Movie application) (10.08 Mbps for DVD)
The BD system has the potential for future higher speed drives.
The BD-RE (rewritable) standard is now available; to be followed by the BD-R
(recordable) and BD-ROM formats in mid-2004, as part of version 2.0 of the Blu-ray specifications.
BD-ROM pre-recorded media are to be available by late 2005. Looking further ahead in time, Blu-ray
Discs with capacities of 100GB and 200GB are currently being researched, with these capacities
achieved by using four and eight layers respectively.
3.4 CODECS
The BD-ROM format will likely include 3 codecs: MPEG-2 (the standard used for
DVDs), MPEG-4's H.264/AVC codec, and VC-1 based on Microsoft's Windows Media 9 codec.
The first codec only allows for about two hours of storage on a single layer Blu-ray Disc, but with the
addition of the latter two more advanced codecs, a single-layer disc can hold almost four hours. Highdefinition
MPEG-2 has a data rate of about 25Mbps, while the latter two have data rates of about
I5Mbps for video and 3Mbps for audio.
BD-RE (and by extension BD-R) does not currently support any advanced
codecs beyond MPEG-2. Because MPEG-2 is currently used to broadcast HDTV, recorders write
this HD stream directly to a disc. Since there are no consumer level recorders capable of real-time
transcoding from the MPEG-2 used for broadcasting and any other codec that might be used for BDRE,
MPEG-2 is the only format supported by BD-RE.
Seminar report on Blu-Ray Disc
Department of Computer Science,CUSAT 21
Encoding methods for the audio stream include Linear PCM, Dolby Digital,
DTS and dts++ (loss less compression). The Blu-ray Disc Association is known to be looking into
other codecs superior to those supported by the DVD specification.
3.5 VARIATIONS
An 8 cm BD specification has been finalized and approved. A one-sided, singlelayer
8 cm BD can hold 15 GB, giving it the capacity of one and a half regular sized (12 cm) single
sided double layer DVDs. This would be an ideal format for small, portable devices, such as portable
movie players and digital video cameras. A new hybrid Blu-ray / DVD combo disc has been developed
by JVC and is awaiting acceptance by the Blu-ray Disc Association. This would allow both normal DVD
players and Blu-ray players to utilize the disc .Users would be able to purchase a single disc that can play
at either high definition or standard DVD quality, depending on the hardware utilized. Users that do not
have a Blu-ray disc player can view the video content at standard definition using their current DVD
player, and enjoy the same content at high definition resolution when upgrading to a Blu-ray disc player
in the future.
3.6 COMPATIBILITY
The BDA announced that, while it was not compulsory for manufacturers, Blu-ray lasers and
drives are capable of reading the various DVD formats, ensuring backward compatibility. This
makes the upgrade more attractive to consumers as it does not require replacing their collections of
DVDs.
3.7 RECORDERS
The first Blu-ray recorder was unveiled by Sony on March 3, 2003, and was introduced to the
Japanese market in April that year. On September 1, 2003, JVC and Samsung Electronics
announced Blu-ray based products at DFA in Berlin, Germany. Both indicated that their
products would be on the market in 2005.
In March 2004,both Sony and Matsushita announced plans to ship 50 GB Blu-ray recorders
the same year. The Matsushita product is to ship in July 2004 in the Japanese market under the
Panasonic brand. Sony is to follow by the end of 2004 and has announced that the Play station
3 will be shipped with a special Blue-ray drive. Meanwhile ,LG Electronics is expected to ship
a recorder equipped with a 200GBhard disk into the U.S. market by Q3 2004. These products
are to support single-sided, dual-layer rewriteable discs of 54GB capacity , Sonyâ„¢s machine will
Seminar report on Blu-Ray Disc
Department of Computer Science,CUSAT 22
also support BD-ROM pre-recorded media, which are expected to be available by Christmas
2005.
CHAPTER-4
CURRENT TECHNOLOGY
4.1 CURRENT STORAGE DEVICES
Some of the popular storage devices that are available in the market include:
Analog Storage Technology
¢ VHS
Digital Storage Technology
¢ Floppy Disc
¢ Compact Disc (CD)
¢ Digital Versatile Disc (DVD)
Seminar report on Blu-Ray Disc
Department of Computer Science,CUSAT 23
4.2 BLU-RAY Vs VHS
The Blu-ray Disc recorder represents a major leap forward in
video recording technology as it enables recording of high-definition television
(HDTV). It also offers a lot of new innovative features not possible with a traditional
VCR:
¢ Random access, instantly jump to any spot on the disc
¢ Searching, quickly browse and preview recorded programs in real-time
¢ Create play lists, change the order of recorded programs and edit recorded video
¢ Automatically find an empty space to avoid recording over programs
¢ Simultaneous recording and playback of video (enables Time slip/Chasing
playback)
¢ Enhanced interactivity, enables more advanced programs and games
¢ Broadband enabled, access web content, download subtitles and extras
¢ Improved picture, ability to record high-definition television (HDTV)
¢ Improved sound, ability to record surround sound (Dolby Digital, DTS, etc)
4.3 BLU-RAY Vs OTHER STORAGE DEVICES
Seminar report on Blu-Ray Disc
Department of Computer Science,CUSAT 24
The storage capacity of different digital storage technology varies a lot. A
usually used version of floppy disc has a capacity of 1.44MB while that of a CD is 700 MB
& for DVD it is 4.7 GB. Also they have varying shell lives out of these DVD has the
maximum. A DVD is very similar to a CD, but it has a much larger data capacity. A standard
DVD holds about seven times more data than a CD does. This huge capacity means that a
DVD has enough room to store a full-length, MPEG-2-encoded movie, as well as a lot of other
information. DVD can also be used to store almost eight hours of CD-quality music per side.
DVD is composed of several layers of plastic, totaling about 1.2 millimeters thick. Each layer
is created by injection molding polycarbonate plastic.
COMPARISON OF BD AND DVD
A disc in the DVD format can currently hold 4.7 gigabytes of data. Unlike
DVD technology, which uses red lasers to etch data onto the disc, the Blu-ray disc
technology uses a blue-violet laser to record information.
The blue-violet laser has a shorter wavelength than the red lasers do, and with its
Parameters BD-ROM DVD-ROM
_ Storage capacity (single-layer) 25GB 4.7GB
_ Storage capacity (dual-layer) 50GB 9.4GB
_ Laser wavelength 405nm 650nm
_ Numerical aperture (NA) 0.85 0.60
_ Protection layer 0.1mm 0.6mm
_ Data transfer rate (1x) 36.0Mbps 11.08Mbps
Seminar report on Blu-Ray Disc
Department of Computer Science,CUSAT 25
smaller area of focus, it can etch more data into the . The digital information is etched on
the discs in the form of microscopic pits. These pits are arranged in a continuous spiral track
from the inside to the outside.
Using a red laser, with 650 nm wavelength, we can only store 4.7 GB on a single
sided DVD. TV recording time is only one hour in best quality mode, and two, three or
four hours with compromised pictures. Data capacity is inadequate for non-stop backup of a
PC hard drive. The data transfer rate, around 10 Mbps, is not fast enough for high quality
video.
Seminar report on Blu-Ray Disc
Department of Computer Science,CUSAT 26
CHAPTER-5
NEXT GENERATION TECHNOLOGIES
5.1 BLU-RAY Vs HD-DVD
Next generation optical disc format developed by Toshiba and NEC. The
format is quite different from Blu-ray, but also relies heavily on blue-laser technology to
achieve a higher storage capacity. The read-only discs (HD DVD-ROM) will hold 15GB and
30GB, the rewritable discs(HD DVD-RW) will hold 20GB and 32GB, while the recordable
discs (HD DVD-R) won't support dual-layer discs, so they will be limited to 15GB. The format
is being developed within the DVD Forum as a possible successor to the current DVD
technology.
5.2 UPCOMING OF RIVALS
The technology is proven, but that's no guarantee of a smooth migration.
Already, a standards war much like those that have broken out over every major medium
since the videocassette is threatening this latest optical innovation. The nine electronics
companies, led by Sony, Pioneer, and Matsushita Electric Industrial, unveiled a standard
format dubbed the Blu-ray Disc, which incorporates blue-violet laser technology and sets
the recording capacity of the disks between 23 and 25 gigabytes per side. Within the
coalition, Sony, Matsushita, and Hitachi have demonstrated prototypes of lasers that meet the
requirements.
5.3 HD DVD AS A CONTESTEE
The group (BDF), however, faces competition on several fronts. On one side
stands Toshiba Corp, which has refused to endorse the Blue-ray Disc. That's troubling
because in the early 1990s, Toshiba led the alliance of electronics and film companies
that produced the standard for today's DVD systems, trouncing a competing effort by
Sony and Royal Philips Electronics of the Netherlands. Earlier this year, Toshiba, which
Seminar report on Blu-Ray Disc
Department of Computer Science,CUSAT 27
continues to head the DVD Forum, demonstrated its own rewritable optical disk,
boasting a capacity of 30 GB per side. And Toshiba is not the only holdout: Mitsubishi
Electric and AOL Time Warner, both important members of the DVD Forum, have yet
to join the Blue-ray Disc group.
The Toshiba is developing another kind of disc using the BLUE LASER
Technology under name AOD (Advanced Optical Disc) more popularly known as HD
DVD (High Definition DVD).And this technology is also backed up by the DVD Forum
similar to the BDF
Toshiba has developed an alternative version and NEC and a provisional
specification approved by the DVD Forum. The original name was AOD (Advanced
Optical Disc).
There are three versions in development.
1. HD DVD-ROM discs are pre-recorded and offer a capacity of 15 GB per layer per
side. These can be used for distributing HD movies.
2. HD DVD-RW discs are re-writable and can be used to record 20 GB per side for
re- writable versions.
3. HD DVD-R discs are write-once recordable format discs with a capacity of
15 GB per side.
Like Blu-ray discs they need a blue laser of 405 nm wavelength, but are
physically similar to DVD discs, as they use a cover layer of 0.6 mm. Therefore HD DVD
discs can be manufactured using existing DVD lines, and existing UV mastering equipment.
5.4 COMPARISON OF FORMATS
The following table provides a comparison of the two formats . It is not yet clear
which format will win. Blu-ray currently seems to have the most support, but HD DVD
Seminar report on Blu-Ray Disc
Department of Computer Science,CUSAT 28
presents fewer manufacturing problems, particularly for pre-recorded versions. HD DVD can
be mastered and replicated with current equipment, while Blu-ray requires new equipment and
processes for both.
CHAPTER 6
LOOKING FORWARD
Sony currently has plans for at least three generations of Professional Disc products, with
PARAMETERS
BD
BD
HD-DVD
HD-DVD
Storage capacity
25GB
50GB
15GB
30GB
Number of layers
Single -layer
Dual “layer
Single -layer
Dual -layer
Laser wavelength
405nm
405nm
405nm
405nm
Numerical aperture (NA)
0.85
0.85
0.65
0.65
Protection layer
0..l mm
0.l mm
0.6mm
0.6mm
Data transfer rate
54.0Mbps
54.0Mbps
36.5Mbps
36.5Mbps
Video compression
MPEG-2
MPEG-4
AVC
VC-1
MPEG-2
MPEG-4
AVC
VC-1
MPEG-2
AVC
MPEG-4
MPEG-2
AVC
MPEG-4
Seminar report on Blu-Ray Disc
Department of Computer Science,CUSAT 29
the goal of doubling capacity and performance with each release. The second-generation
discs are expected sometime in 2005, featuring 50GB of storage capacity on a singlesided,
double-layer disc with a transfer rate of 18MB per second. The company plans to
release third-generation discs in 2007, with a project and implimentationed storage capacity of 100GB using
double-sided media and offering a transfer rate of 36MB per second The 25 GB capacity will
increase later to 50GB, thanks to dual layer discs, proposed by Panasonic. The Blu-Ray
group is still discussing whether the disc can be naked or must be housed in a protective
cartridge.
Existing CD and DVD players and recorders will not be able to use Blu-Ray
discs. New Blu-Ray players will need infra-red, red and blue lasers if they are also to play
all kinds of CD and DVD recordings.
According to industry analysts (In-Stat/MDR) "The EL6900C and the Blu-Ray
disc recording standard will meet the surging demand for increased disc-based video and data
recording capacity.
We project and implimentation this new technology will propel the DVD rewritable market to 62
million units worldwide in 2006 and Intersil is paving the way with its new drivers".
Sony will target commercializing the newly developed 3-wavelength optical head within
2 years, and will positively promote to further technology development. By doing so, in
addition to further reducing the number of parts used for achieving smaller size of optical
heads, enhancement of productivity and reliability will be achieved. This will contribute
to the BD market expansion by realizing BD related key devices to be utilized in various
AV and IT products
CHAPTER-7
CONCLUSION
Anyone old enough to recall fond memories of Rubik's Cubes, Family Ties, and
Duran Duran likely remembers another '80s phenomenon: the VHS vs. Betamax war.
The two competing video-recording technologies emerged together in the 1970s,
when Sony's (NYSE: SNE) Betamax VCR, a pioneer in the industry, fought for market
Seminar report on Blu-Ray Disc
Department of Computer Science,CUSAT 30
share against a rival VHS version developed by Matsushita (NYSE: MC).
VHS technology quickly gained widespread acceptance, while Betamax
followed a divergent path into obscurity. In 1988, with less than 5% of the market, Sony
finally threw in the towel by announcing plans to market a VHS-based recorder. While the
end came slowly, the decision would prove to be a death knell for the Betamax name.
Fast-forward to today. The growing popularity of high-definition television
(HDTV) has fostered a new wave of recording technology, soon to supplant the VCR, and
possibly even DVD. Again, two competing technologies are vying for acceptance, but this
time Sony appears to be on the winning side.
The Blu-ray Disc Founders (not to be confused with the effusively painted
Blue Man Group) is a consortium of 13 leading electronics firms. It has developed a
superior optical disc known as the Blu-ray Disc (BD). As opposed to the red lasers currently
used to produce DVDs, blue beams have a shorter wavelength, allowing for enhanced
precision and more tightly compressed data. While a typical DVD holds 4.7 GB of
information, a BD contains 25 GB - enough storage for two hours of HDTV or 13 hours of
standard television. Dual-layer discs under development will hold an astounding 54 GB. Aside
from greater storage capacity, Blu-ray discs will also contain more interactive features.
The world's two foremost computer manufacturers, Hewlett-Packard (NYSE: HPQ)
and Motley Fool Stock Advisor holding Dell Computer (NASDAQ: DELL), were formally
added to the Blu-ray alliance, virtually ensuring the future adoption of BD technology for PC data
storage.
The competing format, known as HD-DVD, is simultaneously under joint development by
Toshiba and NEC. Though HD-DVD technology appears to be an underdog at this point, it
has recently gained notoriety by winning the support of the DVD forum, a confederation of
DVD-related companies.
Blu-ray, has already earned an early endorsement from Columbia TriStar
Pictures (Hollywood), which has committed to using the Blu-ray technology.
Though BDs are not yet mainstream, and pro forma revenue project and implimentationions are still
being formulated, the technology is moving quickly. The Sony BDZ-S77, a BD recorder, is
already on the shelves in HDTV-dominated Japan, and LG Electronics intends to
introduce its brand to U.S. consumers as early as the third quarter of this year.
Further, with consumers clamoring for faster transfer speeds and storage capacity (two
Seminar report on Blu-Ray Disc
Department of Computer Science,CUSAT 31
of the more notable advantages of BD technology), it's possible that the industry is headed to a
point where BD sales will one day outstrip DVDs. It's too early to call the game just yet, but
this will be an interesting technological development to follow.
REFERENCES
iDocuments
Seminar report on Blu-Ray Disc
Department of Computer Science,CUSAT 32
White paper Blu-ray disc (Sony-march 2005)
iWebsites
bluray.com
blu-raytalk.com
opticaldisc-systems.com
gizmodo.com
iJournals
Electronics For You February 2005
Use Search at http://topicideas.net/search.php wisely To Get Information About Project Topic and Seminar ideas with report/source code along pdf and ppt presenaion
Reply
project report tiger
Active In SP
**

Posts: 1,062
Joined: Feb 2010
#4
02-02-2010, 02:23 PM


.ppt   BLURAY-DISC new.ppt (Size: 538.5 KB / Downloads: 455)


Foundation
Blu-ray disc (BD) is appropriately named after the blue laser
used to write the data
The first blue laser was developed in 1996 by Shuji Nakamura
(Nichia Corporation)
In 2002, an alliance was formed, called the Blu-ray Disc
Association, including the likes of Sony, Samsung, Sharp,
Hewlett-Packard, and Royal Phillips
The e is intentionally left out of the name due to trademark
restrictions
Evolution
VHS: analog
DVD: digital
BD: high-definition
Enables recording, rewriting, and playback of high-definition
video
Capable of storing information that the DVD and CD are not
capable of holding
Disc Characteristics
Single layer: 25 GB
Dual layer: 50 GB
Diameter: 120 mm
Thickness: 1.2 mm
Center hole diameter: 15 mm
Uses GaN laser of wavelength 400 nm
The smaller laser, compared to the DVD and CD, keeps the process
more efficient (~5 mW)
Reply
seminar topics
Active In SP
**

Posts: 559
Joined: Mar 2010
#5
28-03-2010, 10:53 PM

INTRODUCTION:
BD --> Blu-Ray Disc
The founding stones for the Blu Ray Disc technology were laid in 2002 by the Blu Ray Disc Association (BDA) in an attempt to overcome the drawbacks in DVD's. This attempt has almost reached the zenith & the world now is shortly about to use a disc of an incrediblestorage capacity & with almost all the apex features incorporated, that ensures user security and privacy and enables one to operate the disc in the most efficient and convenient way ever imagined.
WHY BD?
Early in 1997, a new technology emerged that brought digital sound and video into homes all over the world almost thrashing out the then conventional CD's. It was called DVD, and it revolutionized the movie industry. This format ruled the market for over a span of 5 years, but now is facing some very tight challenges. Here are some reasons why thereâ„¢s been a rush to change from the current format of DVD:
SIZE : A single-sided, standard DVD can hold 4.7 GB (gigabytes) of information. That's about the size of an average two-hour, standard-definition movie with a few extra features. But a high-definition movie, which has a much clearer image, takes up about five times more bandwidth and therefore requires a disc with about five times more storage. As TV sets and movie studios make the move to high definition, consumers are going to need playback systems with a lot morestorage capacity , which a DVD cannot support. Also, more space on a single disc invariably results in higher disc size. This bulky size of the disc is neither convincing nor convenient.
SECURITY : CSS is toast, thanks to some smart programmers in Europe and some foolish programmers at the now-defunct Xing Technologies. The group that created the DeCSS software figured out how to break the encryption by reverse engineering Xing's DVD decryption key, which wasn't properly protected. The end result is that DVDs can be copied as easily as music CDs. The market hates the fact that the DVD format is now vulnerable and there's nothing they can do about it, and are eager for a new format that is much more secure.
QUALITY : The final reason for the change is video quality. DVD video is presented in 480p, or 480 lines per screen, progressive scanned video. High Definition TV (HDTV) is presented in 720p or 1080i. You won't notice any difference without a high definition television, but if you do have an HDTV set, the improvement in quality is very noticeable. The quality of the video o/p of themedia files on a DVD or a CD is not up to the mark.
SOLUTION :
The industry is set for yet another revolution with the introduction of Blu-ray Discs (BD). With their high storage capacity, Blu-ray discs can hold and playback large quantities of high-definition video and audio, as well as photos, data and other digital content. Also incorporated are some advancedsecurity and privacy options and convenient accessibility features. A single sided blu ray disc has the capacity to store information of about 27 gigabytes, thatâ„¢s about the size of 13 hr standard definition movie or more than 2.5 hrs of a high definition movie. While the double layered one can store to about 54 gigabytes. This enormous storage capability is considered to be the major plus point of the blu ray disc to that of the conventional DVDâ„¢s in the market right now.
BLU-RAY DISC:
Blu ray disc is the next generation digital video disc. It has an edge over the traditional dvd's & lesser used cd's that it has morestorage capacity with the size of the disc being constant. Also we'll discuss now the other features of this disc which makes it quite unique & gives it a chance to be well adapted in all sorts of applications everywhere.
STRUCTURE:
The structure of the Blu-Ray disc is shown as below. It differs from the traditional DVD that, in a DVD the data is sandwiched between two 0.6mm polycarbonate layers. While in the case of a BD the data layer is placed on a 1.1mm polycarbonate layer. To prevent the data on the top of the disc from getting erased, the data layer is covered by a 0.1 mm protection layer. This makes the size of all the CD's DVD's & the BD's constant. This packing of the data has many advantages which will be discussed in the later sections.
STORAGE:
It should be noticed that whatever form of the disc may be under consideration the data on the disc is stored on a SPIRAL TRACK running from the centre of the disc to the end of the diameter of the disc. This spiral starting from the centre of the disc gives the flexibility for the disc to be smaller in size than that of the conventional 120 mm. On this spiral tracks exists the BUMPS which actually hold the data. These bumps lie all along the spiral track. These bumps are often called pits. Viewed from the top of the disc these bumps look like PITS.
CONSTRUCTION:
The construction of the bumps (spiral track) is explained here from a closer view of the disc. The view is so close that the bumps can be seen clearly. Here each white hole represents a bump (pit). For clear understanding it is effectively compared with a DVD.
The key terms used here are:
1) Pit Length: It is the length of the pit on the spiral track which holds the data.
2) Track Pitch: It is the distance between any two successive tracks.
From the figure above :
The minimum pit length of a BD is 0.15 microns which is more than twice as small as the pits on the DVD which is at minimum 0.4 microns. Also the track pitch of the BD is 0.32 microns which is more than twice as small as that of the DVD which is 0.74 microns. This small pit & reduced track pitch enables the accommodation of a data of about 25 gb on a single sided Blu-Ray disc which is almost 5 times that of a single sided traditional DVD.
DATA ACCESS:
Now a laser beam has to be chosen such that it reads the data in the small sized pits.
Unlike current DVDs, which use a red laser to read and write data, Blu-ray discs uses a blue laser (technically blue-violet). A blue laser has a shorter wavelength (405 nanometers) than a red laser (650 nanometers). The smaller beam focuses more precisely, enabling it to read information recorded in pits that are only 0.15 microns (µm) long.
There would immediately be a question as why not laser beams of even smaller wavelength be used to read the disc which encourages the reduction of pit size and the track pitch. But this practically isnâ„¢t possible. This is because the building material of discâ„¢s i.e. the plastic loose durability when lasers of wavelength shorter than 600 nm are focused on them & some plastics the effect was as if they are sun burnt. A wavelength of 405 was found the least for plastic surfaces.
Numerical aperture=0.45 780-nm infrared laser CD
Numerical aperture=0.6 650-nm red laser DVD
Numerical aperture=0.8 405-nm blue laser BD
From the figure above we can conclude that with the reduction in the laser beam wavelength accompanied with an effective (proportional) increase in the lens aperture, it is possible to read & write data into the pits of very small size. This way more disc space can be provided on a BD.
READING ISSUES ::
The till now regularly used DVD's & VCD's face two basic problems regarding their physical structure. They are:
1) Birefringence.
2) Disk tilt.
Birefringence: In a DVD, the data is sandwiched between two polycarbonate layers, each 0.6-mm thick. Having a polycarbonate layer on top of the data can cause a problem called birefringence, in which the substrate layer refracts the laser light into two separate beams. If the beam is split too widely, the disc cannot be read.
Disk Tilt: If the DVD surface is not exactly flat, and is therefore not exactly perpendicular to the beam (laser), it can lead to a problem known as disc tilt, in which the laser beam is distorted. This sometimes may lead to reading or writing into other undesired memory locations.
SOLUTION:
The Blu-ray disc overcomes DVD-reading issues by placing the data on top of a 1.1-mm-thick polycarbonate layer. Having the data on top prevents birefringence and therefore prevents readability problems. And, with the recording layer sitting closer to the objective lens of the reading mechanism, the problem of disc tilt is virtually eliminated.
FILE SYSTEM : The file system here has two important aspects of consideration:
1) Data arrangement.
2) Data retrieval.
1) DATA ARRANGEMENT: The general file system used in Blu -Ray disc is quite unique. It divides entire disk space into two parts.
a) Metadata & Database area.
b) Real time Recordable area.
The real time recordable area is the major part in respect to size on the disc & it contains the real time files used by the user. They vary from a/v streams to s/w programs to documents. While the Metadata & Database area holds the information that manages the data in the real time recordable area. . This MD files actually serves as a means of quick access to the folders & enable the users to open (operate) multiple directories at the same time & help during the system scan & others. In addition to the MD area on the disc, in order to provide robustness, a backup of the MD area files is provided. The files recorded in the area for metadata and database files can be read with a fewer number of seeks, reducing the response time during Play List editing and menu display, resulting in greatly improved system response.
There exists different file systems (derivative of the general one)for different versions of the BD that are BD-ROM , BD-Rewritable , BD-Recordable.
Blu-ray Rewritable discs are non-sequential recording media, where read-modify-write and defect management operations are performed by drive unit, eliminating the need for the Virtual Allocation Table and Sparing Table in the file system.
Blu-ray Recordable discs also include defect management, eliminating the need for the Sparing Table inthe file system. The defect management system allows for the replacement of defective clusters as well as enabling the logical overwriting of previously recorded user data. For Blu-ray Read-Only discs, the requirements are simplified since there is no need for read-modify-write, overwriting or incremental recording of user data.
2) DATA RETRIEVAL (CONTINUOUS):
When recording, deleting or editing operations are performed repeatedly, small areas of empty space will occur across the disc. These small areas can be used to record a new Real-Time file, which results in a single Real-Time file composed of many small extents scattered across the disc. A group of these extents, each of which is recorded on contiguous logical sectors, is called an Expanse. The Expanse is conceptually a contiguous area to be read, and may include small areas in which Real-Time data is not recorded.
When a single Real-Time file is made up of several expanses, the file is read by jumping from one expanse to the next and reading the expanses in order. However, when jumping from one expanse to another, the disc rotation speed needs to be changed and the optical pickup needs to be moved to a different radius on the disc. Although data cannot be retrieved from the disc during this interval, the decoding/playback of video/audio data must continue without interruption.
To prevent interruption in video/audio playback while reading data from the disc, the buffer memory must not be emptied of data before readout from the next expanse becomes possible. This requirement for continuous supply of data is necessary to insure seamless playback. Therefore the minimum expanse size is defined such that the buffer memory does not become empty when jumping from one expanse to another on the disc.
Utilities :
The file system for a general Blu-Ray disc is mentioned just above. The information about the locations of different expanses of a single file is maintained in the Meta database region of the BD. The utilities of this unique format (file system) are found maximum in the BD-R amongst the BD-R, BD-ROM, and BD-RW formats. Those utilities are mentioned below:
1) Digital Broadcasting Direct Recording Function :
This recording function enables the recording of not only digital broadcast image data without destroying the image quality, but also of data broadcast data and multi-channel sound data altogether. To this end, this format employs the MPEG-2TS (Transport Stream), used by digital broadcasts, as a stream type for recording. Received MPEG-2TS data is recorded on a disc as a Clip AV stream file.
This is mainly enabled by the capability of the Blu-Ray disc of outputting at the rate of 36 Mbps which is more than 3.5 times that of the DVD which is 10 Mbps. This high rate enables both the recording & the data broadcast.
2) Random Access High-speed Playback Function :
To achieve a function that enables random access to a desired scene in MPEG-2TS and high-speed playback, tables to obtain the record position of data corresponding to a playback time requested by the user are provided for each Clip AV stream file. The tables are stored in the Clip Information File.
3) Editing and Marking Function:
The Play List file is provided for removing unnecessary scenes without copying or transferring recorded data like tape media, and editing material recorded on the disc without processing the original image. The Play List file holds the playback order information necessary to designate what part of what Clip AV stream is played back.
4) Contents Search Function:
In each thumbnail related file, thumbnails of the Play List file and bookmarked scenes are stored. This enables the search for recorded contents and bookmarks by viewing thumbnail images.
The last 3 utilities mainly depend on the Meta database information of the real time data stored on the centre of the disc & the backup of which is stored at the end of the disc diameter. The table representing the position of the data corresponding to the playback time is shown in the figure below. This same list is used for the searching & playing the selected part of the media (play list).
TECHNOLOGICAL AID :
1) Laser and optics
Blu-ray systems use a "blue" (technically blue-violet) laser operating at a wavelength of 405 nm to read and write data. Conventional DVDs and CDs use red and infrared lasers at 650 nm and 780 nm respectively.
The blue-violet laser's shorter wavelength makes it possible to store more information on a 12 cm CD/DVD sized disc. The minimum "spot size" on which a laser can be focused is limited by diffraction, and depends on the wavelength of the light and the numerical aperture of the lens used to focus it. By decreasing the wavelength, using a higher numerical aperture (0.85, compared with 0.6 for DVD), higher quality, dual-lens system, and making the cover layer thinner to avoid unwanted optical effects, the laser beam can be focused much more tightly at the disk surface. This produces a smaller spot on the disc and allows more information to be physically contained in the same area. In addition to the optical improvements, Blu-ray Discs feature improvements in data encoding, allowing for even more data to be packed in. (See compact disc for information on optical discs' physical structure.)
2) Hard-coating technology
Because the Blu-ray standard places data so close to the surface of the disc, early discs were susceptible to dust and scratches & fingerprints and had to be enclosed in plastic caddies for protection. Such an aggravation, the consortium worried, would hobble Blu-ray's adoption in the face of the rival HD DVD standard; HD DVDs can be handled bare (caddy less) like CDs and DVDs, making them familiar to consumers as well as attractive to manufacturers and distributors who might be deterred by additional costs.
The solution to this problem arrived in January 2004 with the introduction of a clear polymer that gives Blu-ray discs unprecedented scratch resistance. The coating, developed by TDK Corporation under the name "Durabis," allows BD™s to be cleaned safely with only a tissue”a procedure that can damage CDs, DVDs, and (presumably) HD DVDs, which are manufactured by the same process as these older optical media. Bare BD™s with the coating are reportedly able to withstand attack by a screwdriver.
Durabis is a brand name for a clear polymer coating developed by the TDK Corporation. One of its principal applications at first will be for scratch-resistance in Blu-ray and other optical disks. It is claimed to be tough enough to resist screwdriver damage and make scratched optical disks (CD and DVDs) a thing of the past.
In order to meet Blu-ray's specifications, TDK's coating had to be less than 0.1 mm thick, be hard enough to resist considerable damage and yet be transparent enough to be easily read. This process essentially spin-coats two layers onto discs. One is for protection against scratches and the other protects against stains and oils.
3) Codecâ„¢s
The BD-ROM format specifies at least three video codecâ„¢s: MPEG-2, the standard used for DVDs; MPEG-4's H.264/AVC codec; and VC-1, a codec based on Microsoft's Windows Media 9. The first of these only allows for about two hours of high-definition content on a single-layer BD-ROM, but the addition of the two more advanced codecâ„¢s allows up to four hours per layer.
For audio, BD-ROM supports linear (uncompressed) PCM, Dolby Digital, Dolby Digital Plus, DTS, DTS-HD, and Dolby Lossless (a lossless compression format also known as MLP).
In order to remain backwards compatible, BD-RE (and by extension BD-R) will by and large support the MPEG2 codec. For users recording digital television broadcasts, the Blu-ray's baseline data rate of 36Mbit will be more than adequate to record high definition broadcasts. Support for new codecâ„¢s will evolve as new codecâ„¢s are encapsulated by broadcasters into their MPEG2 transport streams and consumer set top boxes capable of decoding them are rolled out.
4) Java Software Support
At the 2005 Java One trade show, it was announced that Sun Microsystems' Java cross-platform software environment would be included in all Blu-ray players as a mandatory part of the standard. Java will be used to implement interactive menus on Blu-ray discs, as opposed to the method used on DVD video discs, which uses pre-rendered MPEG segments and selectable subtitle pictures and is considerably more primitive. Java creator James Gosling, at the conference, suggested that the inclusion of a Java virtual machine as well as network connectivity in BD devices will allow updates to Blu-ray discs via the Internet, adding content such as additional subtitle languages and promotional features that are not included on the disc at pressing time. This Java Version will be called BD-J and will be a subset of the GEM (Globally Executable MHP) standard. GEM is the world-wide version of the Multimedia Home Platform standard.
5) Compatibility
While it is not compulsory for manufacturers, the Blu-ray Disc Association recommends that Blu-ray drives should be capable of reading DVDs, ensuring backward compatibility.
JVC has developed a three layer technology that allows putting both standard-definition DVD data and HD data on a BD/DVD combo disc. If successfully commercialized, this would enable the consumer to purchase a disc which could be played on current DVD players, and reveal its HD version when played on a new BD player.
6) Security
Blu-ray has an experimental security feature titled BD+ that allows for dynamically changing encryption schemes. Should the encryption be compromised, manufacturers can update the encryption scheme and put it on all new discs, preventing a single crack from opening up the entire specification for the duration of its lifetime. It also uses the Mandatory Managed Copy system allowing users to securely rip a file into a secure format, a feature originally requested by HP. The lack of a dynamic encryption model is what made DeCSS so disastrous in the industry's eyes: once CSS was cracked, all DVDs from then on were crack able.
The Blu-ray Disc Association also agreed to add digital watermarking technology to the discs. Under the name "ROM-Mark," this technology will be built into all ROM-producing devices, and prevent content from being reproduced in the event that a watermark is detected. Through licensing, the BDA believes that it can eliminate the possibility of mass producing BD-ROMs without authorization.
PROS :
() High disc space at almost same cost price
() Security
() reverse compatibility
() high speed data transfer (36Mbps)
() online modifications
CONS :
() High cost of the disc reader
() less data space than AOD (HD-DVD 30 Giga bytes)
CONCLUSION :
It would definitely take a considerable time for the Blu-Ray disc to hit the market & completely takeovers the DVD share hold. Because of the low level compatibility (BD readers able to read both the DVDâ„¢s and the CDâ„¢s), the task might become a little simpler. But, the high cost of the reader might hinder its quick development. Anyways soon or later this mass storage optical device is going to replace the DVD & let the user experience a world high quality & disc space (Quality & Quantity ensured) with high level of security and privacy ensured.
BIBLOGRAPHY :
1) blu-raydisc.com (official site for blu-ray disc)
2) bitpipe.org (referred to the white paper by john.paulinghton)
3) wikipedia.com (general information source 1)
4) tgdaily.com (referred to a 4 news reports by WARNER BROS and SONY)
5) howstuffworks.com (general information source 2)
SUPPORT :
The rapid strides and the success level of BD is contributed by major organizations such as SONY , WARNER BROTHRS & many others that have joined the BDA (Blu Ray Disc Association) in bringing it into the market such that it satisfies all the needs of the users.
TRIVIA :
The spelling BLU isnâ„¢t any spelling mistake. It indicates that a blue colored laser beam is used in this disc technology. But, under the constraint that no regularly used words should be trademarked this disc is named BLU RAY DISC instead of BLUE RAY DISK.


Attached Files
.docx   Blu Ray Disc.docx (Size: 90.75 KB / Downloads: 117)
Use Search at http://topicideas.net/search.php wisely To Get Information About Project Topic and Seminar ideas with report/source code along pdf and ppt presenaion
Reply
project topics
Active In SP
**

Posts: 2,492
Joined: Mar 2010
#6
04-04-2010, 08:13 PM

please read topicideashow-to-blu-ray-dvd-full-report and topicideashow-to-blu-ray-technology and topicideashow-to-seminar and presentation-report-on-blu-ray-disc for getting more information about Blue ray disk
Use Search at http://topicideas.net/search.php wisely To Get Information About Project Topic and Seminar ideas with report/source code along pdf and ppt presenaion
Reply
project topics
Active In SP
**

Posts: 2,492
Joined: Mar 2010
#7
06-04-2010, 07:33 PM


.ppt   Blu-ray Disc.ppt (Size: 955.5 KB / Downloads: 178)


Blu-ray Disc
What is Blu-ray???

The Blu-ray Disc(BD),also known as Blu-ray,is the name of next generation optical disc format.
The format was developed to enable recording,rewriting and playback of high-definition video and audio(HD) as well as storing large amounts of data.
It has the capability of holding as much as five times more than the storing capacity of traditional DVDâ„¢s.




Why the name Blu-ray??

The name Blu-ray is derived from the underlying technology, which utilizes a blue-violet laser to read and write data instead of the red laser as in the present DVD. The name is a combination of "Blue" (blue-violet laser) and "Ray" (optical ray).
According to the Blu-ray Disc Association the spelling of "Blu-ray" is not a mistake, the character "e" was intentionally left out so the term could be registered as a trademark.
Who developed Blu-ray?

Computer and media manufacturers, with more than 180 member companies from all over the world. The Board of Directors currently consists of: Apple Computer, Inc. Dell Inc. Hewlett Packard Company Hitachi, Ltd. LG Electronics Inc. Matsushita Electric Industrial Co., Ltd. Mitsubishi Electric Corporation Pioneer Corporation Royal Philips Electronics Samsung Electronics Co., Ltd. Sharp Corporation Sony Corporation Sun Microsystems, Inc. TDK Corporation Thomson Multimedia Twentieth Century Fox Walt Disney Pictures Warner Bros. Entertainment
What Blu-ray formats are planned?
As with conventional CDs and DVDs, Blu-ray plans to provide a wide range of formats including ROM/R/RW. The following formats are part of the Blu-ray Disc specification:
BD-ROM - read-only format for distribution of HD movies, games, software, etc .
BD-R - recordable format for HD video recording and PC data storage.
BD-RE - rewritable format for HD video recording and PC data storage.
There's also plans for a BD/DVD hybrid format, which combines Blu-ray and DVD on the same disc so that it can be played in both Blu-ray players and DVD players.
How much data can you fit on a Blu-ray disc??
A single-layer disc can hold 25GB. A dual-layer disc can hold 50GB.
To ensure that the Blu-ray Disc format is easily extendable (future-proof) it also includes support for multi-layer discs, which should allow the storage capacity to be increased to 100GB-200GB (25GB per layer) in the future simply by adding more layers to the discs.
Over 9 hours of high-definition (HD) video on a 50GB disc. About 23 hours of standard-definition (SD) video on a 50GB disc.
How fast can you read/write data on a Blu-ray disc?
According to the Blu-ray Disc specification, 1x speed is defined as 36Mbps. However, as BD-ROM movies will require a 54Mbps data transfer rate the minimum speed we're expecting to see is 2x (72Mbps).
Blu-ray also has the potential for much higher speeds, as a result of the larger numerical aperture (NA) adopted by Blu-ray Disc. The large NA value effectively means that Blu-ray will require less recording power and lower disc rotation speed than DVD and HD-DVD to achieve the same data transfer rate. While the media itself limited the recording speed in the past, the only limiting factor for Blu-ray is the capacity of the hardware. If we assume a maximum disc rotation speed of 10,000 RPM, then 12x at the outer diameter should be possible (about 400Mbps). This is why the Blu-ray Disc Association (BDA) already has plans to raise the speed to 8x (288Mbps) or more in the future.
What video codecs will Blu-ray support?
MPEG-2 - enhanced for HD, also used for playback of DVDs and HDTV recordings.
MPEG-4 AVC - part of the MPEG-4 standard also known as H.264 (High Profile and Main Profile).
SMPTE VC-1 - standard based on Microsoft's Windows Media Video (WMV) technology.
What audio codecs will Blu-ray support
Linear PCM (LPCM) - up to 8 channels of uncompressed audio. (mandatory)
Dolby Digital (DD) - format used for DVDs, 5.1-channel surround sound. (mandatory)
Dolby Digital Plus (DD+) - extension of Dolby Digital, 7.1-channel surround sound. (optional)
Dolby TrueHD - lossless encoding of up to 8 channels of audio. (optional)
DTS Digital Surround - format used for DVDs, 5.1-channel surround sound. (mandatory)
DTS-HD High Resolution Audio - extension of DTS, 7.1-channel surround sound. (optional)
DTS-HD Master Audio - lossless encoding of up to 8 channels of audio. (optional)
What resolution will the video on a movie BD be?
BD resolution will follow the standard HD resolution standards currently used for HDTV transmissions. This means, at least for the present, the maximum resolution will be 1080i/p, or 1920x1080 in either interlaced or progressive format (not many displays can support 1080p, and even less can resolve or display the full 1080 lines). There is also 720p resolution (1280x720, progressive), which is the current native resolution of many home theatre displays, and also SD resolution support, similar to today's DVDs.
Will Blu-ray replace DVDs???

Yes, that's the expectation. The Blu-ray format has received broad support from the major movie studios as a successor to today's DVD format. In fact, seven of the eight major movie studios (Disney, Fox, Warner, Paramount, Sony, Lionsgate and MGM) are supporting the Blu-ray format. Many studios have also announced that they will begin releasing new feature films on Blu-ray Disc day-and-date with DVD, as well as a continuous slate of catalog titles every month.

What is the difference between Blu-ray and DVD?
Will Blu-ray be backwards compatible with DVD?

Yes, several leading consumer electronics companies (including Sony, Panasonic, Philips, Samsung, Pioneer, Sharp and LG) have already demonstrated products that can read/write CDs, DVDs and Blu-ray discs using a BD/DVD/CD compatible optical head, so you don't have to worry about your existing DVD collection becoming obsolete. In fact, most of the Blu-ray players coming out will support upscaling of DVDs to 1080p/1080i, so your existing DVD collection will look even better than before. While it's up to each manufacturer to decide if they want to make their products backwards compatible with DVD, the format is far too popular to not be supported. The Blu-ray Disc Association (BDA) expects every Blu-ray Disc device to be backward compatible with DVDs.
What about Blu-ray for PCs?

There are plans for BD-ROM (read-only), BD-R (recordable) and BD-RE (rewritable) drives for PCs, and with the support of the worlds two largest PC manufacturers, HP and Dell, it's very likely that the technology will be adopted as the next-generation optical disc format for PC data storage and replace technologies such as DVD±R, DVD±RW, and DVD-RAM.
Is Blu-ray the same thing as HD- DVD?
No, HD-DVD (previously known as AOD) is the name of a competing next-generation optical disc format developed by Toshiba and NEC.
The format is quite different from Blu-ray, but also relies heavily on blue-laser technology to achieve a higher storage capacity.
The format is being developed within the DVD Forum as a possible successor to the current DVD technology
Blu-ray vs HD-DVD?

What benefits does Blu-ray offer compared to HD-DVD?
Although both Blu-ray and HD-DVD are similar in many aspects, there are some important differences between them :

.
The first is capacity. Because Blu-ray utilizes a lens with a greater numerical aperture (NA) than HD-DVD, the laser spot can be focused with greater precision to fit more data on the same size disc. This allows Blu-ray to hold 25GB per layer (50GB on a dual-layer disc), whereas HD-DVD can only hold 15GB per layer (30GB on a dual-layer disc). Blu-ray has also adopted a higher data transfer rate for video and audio (54Mbps vs 36.55Mbps). The greater capacity and data transfer rates for Blu-ray will allow the movie studios to release their movies with higher quality video and audio than the HD-DVD format.
What benefits does Blu-ray offer compared to HD-DVD?
The second is content. The Blu-ray format has received broad support from the major movie studios as a successor to today's DVD format. Seven of the eight major movie studios (Warner, Paramount, Fox, Disney, Sony, MGM and Lionsgate) have already announced titles for Blu-ray, whereas HD-DVD only has support from three major movie studios (Warner, Paramount and Universal). This is an important difference because some of the studios might only support one of the formats, so you won't be able to get your favorite movies in the other format. Choosing the format with the most content support minimizes this risk.

The third is hardware support. The Blu-ray format has broad support from the world's leading consumer electronics, personal computer and media manufacturers, including Sony, Panasonic, Philips, Samsung, Pioneer, Sharp, JVC, Hitachi, Mitsubishi, TDK, Thomson, LG, Apple, HP and Dell. The Blu-ray format will also be supported in the next-generation PlayStation 3 (PS3) video game console. This means that you will have a lot of choice when it comes to players and hardware. The HD-DVD format has far less supporters, so the amount of players and hardware will be very limited. Currently, Toshiba is the only company offering a stand-alone HD-DVD player.
Building a Blu-ray Disc.
Discs store digitally encoded video and audio information in pits -- spiral grooves that run from the center of the disc to its edges.
A laser reads the other side of these pits -- the bumps -- to play the movie or program that is stored on the DVD.
The more data that is contained on a disc, the smaller and more closely packed the pits must be.
The smaller the pits (and therefore the bumps), the more precise the reading laser must be.
Building a Blu-ray Disc¦¦¦¦
Unlike current DVDs, which use a red laser to read and write data, Blu-ray uses a blue laser (which is where the format gets its name).
A blue laser has a shorter wavelength (405 nanometers) than a red laser (650 nanometers).
The smaller beam focuses more precisely, enabling it to read information recorded in pits that are only 0.15 microns (µm) (1 micron = 10-6 meters) long -- this is more than twice as small as the pits on a DVD.
Blu-ray has reduced the track pitch from 0.74 microns to 0.32 microns. The smaller pits, smaller beam and shorter track pitch together enable a single-layer Blu-ray disc to hold more than 25 GB of information -- about five times the amount of information that can be stored on a DVD.
Building a Blu-ray Disc¦..contd.
Each Blu-ray disc is about the same thickness (1.2 millimeters) as a DVD. But the two types of discs store data differently. In a DVD, the data is sandwiched between two polycarbonate layers, each 0.6-mm thick. Having a polycarbonate layer on top of the data can cause a problem called birefringence in which the substrate layer refracts the laser light into two separate beams. If the beam is split too widely, the disc cannot be read. Also, if the DVD surface is not exactly flat, and is therefore not exactly perpendicular to the beam, it can lead to a problem known as disc tilt, in which the laser beam is distorted. All of these issues lead to a very involved manufacturing process.

How Blu-ray Reads Data??

The Blu-ray disc overcomes DVD-reading issues by placing the data on top of a 1.1-mm-thick polycarbonate layer. Having the data on top prevents birefringence and therefore prevents readability problems. And, with the recording layer sitting closer to the objective lens of the reading mechanism, the problem of disc tilt is virtually eliminated. Because the data is closer to the surface, a hard coating is placed on the outside of the disc to protect it from scratches and fingerprints.
Hard coating technology

Because the Blu-ray Disc standard places the data recording layer close to the surface of the disc, early discs were susceptible to contamination and scratches and had to be enclosed in plastic caddies for protection.
The recent introduction of a clear polymer coating has given Blu-ray Discs substantial scratch resistance. The coating is developed by TDK and is called "Durabis". It allows BDs to be cleaned safely with only a tissue. Verbatim recordable and rewritable Blu-ray Disc discs use their own proprietary hard-coat technology called ScratchGuard.


Designing the disc

The design of the Blu-ray discs saves on manufacturing costs. Traditional DVDs are built by injection molding the two 0.6-mm discs between which the recording layer is sandwiched. The process must be done very carefully to prevent birefringence.
The two discs are molded.
The recording layer is added to one of the discs.
The two discs are glued together.
Blu-ray discs only do the injection-molding process on a single 1.1-mm disc, which reduces cost. That savings balances out the cost of adding the protective layer, so the end price is no more than the price of a regular DVD.
Uses of Blu-ray Disc

Blu-ray discs not only have more storage capacity than traditional DVDs, but they also offer a new level of interactivity. Users will be able to connect to the Internet and instantly download subtitles and other interactive movie features. With Blu-ray, you can :
record high-definition television (HDTV) without any quality loss
instantly skip to any spot on the disc
record one program while watching another on the disc
create playlists
edit or reorder programs recorded on the disc
automatically search for an empty space on the disc to avoid recording over a program
access the Web to download subtitles and other extra features
Blu-ray Competitors

In the meantime, JVC has developed a Blu-ray/DVD combo disc with an approximate 33.5-GB capacity, allowing for the release of video in both formats on a single disc. But Blu-ray is not alone in the marketplace. A few other formats are competing for a share of the DVD market.
The other big player is HD-DVD, also called AOD (Advanced Optical Disc), which was developed by electronics giants Toshiba and NEC. HD-DVD was actually in the works before regular DVD, but it didn't begin real development until 2003.
Blu-ray and HD-DVD are the two major competitors in the market, but there are other contenders, as well. Warner Bros. Pictures has developed its own system, called HD-DVD-9. This system uses a higher compression rate to put more information (about two hours of high-definition video) on a standard DVD. Taiwan has created the Forward Versatile Disc (FVD), an upgraded version of today's DVDs that allows for more data storage capacity (5.4 GB on a single-sided disc and 9.8 GB on a double-sided disc). And China has introduced the Enhanced Video Disc (EVD), another high-definition video disc.
The future of Blu-ray Disc..

There are also professional versions of the blue laser technology. Sony has developed XDCAM and ProData (Professional Disc for Data). The former is designed for use by broadcasters and AV studios. The latter is primarily for commercial data storage (for example, backing up servers).
It seems that the future holds a whole lot more than 25 to 54 GB on a single disc. According to T3Tongueioneer goes beyond Blu-Ray, Pioneer is developing an optical disc that will blow away the hard disc in most of our PCs in terms storage capacity, holding 500 GB of data. How so? Pioneer's lasers are ultraviolet, which have an even shorter wavelength than the blue.
Use Search at http://topicideas.net/search.php wisely To Get Information About Project Topic and Seminar ideas with report/source code along pdf and ppt presenaion
Reply
seminar presentation
Active In SP
**

Posts: 582
Joined: Apr 2010
#8
12-05-2010, 11:19 PM


.doc   blu-ray.doc (Size: 86 KB / Downloads: 79)


CONTENTS
ABSTRACT
INTRODUCTION TO BLU-RAY
BLU-RAY VS HD DVD
BUILDING OF BLU-RAY
WORKING OF BLU-RAY
OPERATING SYSTEM SUPPORT
ADVANTAGES & DISADVANTAGES
APPLICATIONS
CONCLUSION
ABSTRACT
In the year 1997 a revolutionary new technology brought music, video entertainment with high definition into the homes in the world and revolutionizing the entertainment industry and that was DVD. Now around after ten years of such an invention in 2006, yet another high definition and highly revolutionizing technology is getting common which is called the Blue-ray technology. Here in this invention discs are called the Blue-ray Discs (BD). These discs have very high storage capacity and can play high quantities of audio, video of high definition together with datas, photos and many varieties of digital contents.
The development effort has differed sharply from the industry efforts that produced CD and DVD technologies. These technologies were marked by compatibility problems associated with competing formats and the fact that they were released in phases. Their writable and rewritable versions designed for PC applications were not developed and released until well after their initial read-only versions. For example, music CD formats were developed and released first, followed by the formats used for PC data storage and backup. The result was a period of transition often marked by incompatibility between discs and drives.
In contrast, Blu-ray Disc technology has broad industry support and was designed from the beginning to accommodate the requirements of PC and consumer electronics applications. In addition, all the formats”read-only, writable, and rewritable”will be released simultaneously. This strategy, coupled with an industry compatibility program, should avoid the compatibility issues experienced with previous optical storage technologies. Blu-ray Discs will be readable in any Blu-ray Disc drive, whether it is in a consumer electronics device or a PC.
Moreover, the discs use the same form factors as existing CD and DVD optical discs.
Introduction to BLU-RAY:
Blue violet laser is used in the Blue-ray discs for reading the information as it has shorter wavelength of 405 nm. Single layered Blue ray discs can store 25 gigabytes which is 5 times more than the DVD ingle layered that can store 4.7 GB. If it is double layered BD it stores 50 GB that is 6 times more than the Double layered DVD can store. The advantages in this blue ray technology over the normal DVD is that user can jump to any point on the disc instantly. High Definition Television can be recorded without the loss of any Quality. User can enjoy recording one program while playing another program on that disc. Recorded program can be edited or reordered. Playlists can be created. Space in the disc can be automatically searched for avoiding overwriting.
In the blue ray discs the data is placed on top of the polycarbonate layer that is 1.1mm thick, this placing of data prevents the reading problems as birefringence is prevented. Outside of the disc is provided with hard coating to protect it from scratches and the fingerprints. Blue ray discs will not be expensive as the production cost of them is less. In a DVD the recorded layer is kept in between two 0.6mm thick discs and then they are molded, and this process requires to be done carefully to avoid birefringence. But for blue ray discs injection molding is done on a single 1.1mm disc. BDs transfer the data very fast with rate of 36 Mbps where as the DVDs transfer at 10 Mbps.
Technical specifications:
* About 9 hours of high-definition (HD) video can be stored on a 50 GB disc.
* About 23 hours of standard-definition (SD) video can be stored on a 50 GB disc.
* On average, a single-layer disc can hold a High Definition feature of 135 minutes using MPEG-2, with additional room for 2 hours of bonus material in standard definition quality. A dual layer disc will extend this number up to 3 hours in HD quality and 9 hours of SD bonus material.
allowing for backward compatibility. In fact, it is expected that Blu-ray Disc drives will be available at launch that can read and write CDs, DVDs, and Blu-ray Discs.
BLU-RAY VS HD DVD :
Now the argument is whether the BDs replace the DVDs, and the manufacturers of the BDs are very hopeful of that, and a company has already developed a Blu-ray/DVD combo disc with around 33.5 GB capacity. As BDs is strong competitor for the DVD there are other equivalent competitors coming for replacing of the DVDs like HD-DVD which is called as AOL (Advanced Optical Device) developed by Toshiba and NEC. But still the blu-ray technology has an edge when compared and next it will be the BDs instead of DVDs. But threat can be from the Pioneerâ„¢s featured technology disc that is said to be of 500 GB capacity and can blow out the hard discs in the systems, this technology is said to use direct ultra violet rays which have even very shorter wavelength than the Blue light.
The Format Wars:
DVDs are the current standard for data storage, and perhaps more importantly the publishing format standard as well. The question is however, how much longer will they be sufficient? A much anticipated battle, or Ëœformat warâ„¢ if you will, is in progress similar to that seen in the 1980â„¢s between VHS and Betamax. This time around the same companies have fallen into the same camps and war is ensuing between Blu-ray and HD DVD technology.
Blu-ray discs (BDs) have the same physical dimensions as CDs and DVDs. But just as DVD provided a substantial increase in storage capacity compared to CD, Blu-ray Disc represents an increase over DVD capacity by 5 to 10 times.
Similar to CD, Blu-ray Disc is being manufactured as a single substrate disc,which is unlike DVD. This manufacturing process does not require the bonding of two substrates, resulting in less production material, shorter production time, and ultimately lower production costs per disc.
Blu-ray formats:
The three types of Blu-ray formats planned: BD-ROM for pre-recorded media such as software, games and movies BD-R (recordable) for HDTV recording and PC data storage BD-RE (rewritable) for HDTV recording and PC data storage
As with all new technology it will initially be more expensive to run.
Capacities:
Blu-ray supports more data capacity per layer compared to HD DVDs. That is 25GB per layer versus 15GB of HD DVD. Technically it can fit three different capacities; 25GB is merely the average, these capacities are 23.3GB, 25GB or 27GB. This equates to over 4 hours of high definition video with audio.
There is also the option of dual-layers: 46.6GB, 50GB or 54GB, which is roughly 8 hours. Currently BDA are researching 100GB and 200GB technology with 4 or 8 layers, this keeps the technology Ëœfuture proofâ„¢. Also in the works is an 8cm disc variation with a 15GB capacity, rather than the regular 12cm discs.
Building a Blu-ray Disc:
Unlike current DVDs, which use a red laser to read and write data, Blu-ray uses a blue laser (which is where the format gets its name). A blue laser has a shorter wavelength (405 nanometers) than a red laser (650 nanometers). The smaller beam focuses more precisely, enabling it to read information recorded in pits that are only 0.15 microns (µm) (1 micron = 10-6 meters) long -- this is more than twice as small as the pits on a DVD. Plus, Blu-ray has reduced the track pitch from 0.74 microns to 0.32 microns. The smaller pits, smaller beam and shorter track pitch together enable a single-layer Blu-ray disc to hold more than 25 GB of information -- about five times the amount of information that can be stored on a DVD

Each Blu-ray disc is about the same thickness (1.2 millimeters) as a DVD. But the two types of discs store data differently. In a DVD, the data is sandwiched between two polycarbonate layers, each 0.6-mm thick. Having a polycarbonate layer on top of the data can cause a problem called birefringence, in which the substrate layer refracts the laser light into two separate beams. If the beam is split too widely, the disc cannot be read. Also, if the DVD surface is not exactly flat, and is therefore not exactly perpendicular to the beam, it can lead to a problem known as disc tilt, in which the laser beam is distorted. All of these issues lead to a very involved manufacturing process
Woking of blu-ray:
The Blu-ray disc overcomes DVD-reading issues by placing the data on top of a 1.1-mm-thick polycarbonate layer. Having the data on top prevents birefringence and therefore prevents readability problems. And, with the recording layer sitting closer to the objective lens of the reading mechanism, the problem of disc tilt is virtually eliminated. Because the data is closer to the surface, a hard coating is placed on the outside of the disc to protect it from scratches and fingerprints.
Source: Blu-ray Disc Association
The design of the Blu-ray discs saves on manufacturing costs. Traditional DVDs are built by injection molding the two 0.6-mm discs between which the recording layer is sandwiched. The process must be done very carefully to prevent birefringence.
1. The two discs are molded.
2. The recording layer is added to one of the discs.
3. The two discs are glued together.
Blu-ray discs only do the injection-molding process on a single 1.1-mm disc, which reduces cost. That savings balances out the cost of adding the protective layer, so the end price is no more than the price of a regular DVD.
Use Search at http://topicideas.net/search.php wisely To Get Information About Project Topic and Seminar ideas with report/source code along pdf and ppt presenaion
Reply
projectsofme
Active In SP
**

Posts: 1,124
Joined: Jun 2010
#9
18-10-2010, 10:42 AM


.doc   Blu-ray disc.doc (Size: 518.5 KB / Downloads: 66)
Blu-ray Disc


ABSTRACT


Optical disks share a major part among the secondary storage devices. Blu-ray Disc is a next-generation optical disc format. The technology utilizes a blue laser diode operating at a wavelength of 405 nm to read and write data. Because it uses a blue laser it can store enormous amounts of data on it than was ever possible.

Data is stored on Blu-Ray discs in the form of tiny ridges on the surface of an opaque 1.1-millimetre-thick substrate. This lies beneath a transparent 0.1mm protective layer. With the help of Blu-ray recording devices it is possible to record up to 4 hours of very high quality audio and video or more than 20 hours of standard-definition TV on a single BD.

Blu-ray also promises some added security, making ways for copyright protections. Blu-ray discs can have a unique ID written on them to have copyright protection inside the recorded streams.

Blu-ray disc takes the DVD technology one step further, just by using a laser with a nice color.


History of Blu-ray Disc

First Generation

When the CD was introduced in the early 80s, it meant an enormous leap from traditional media. Not only did it offer a significant improvement in audio quality, its primary application, but its storage capacity 800 MB also meant a giant leap in data storage and retrieval. For the first time, there was a universal standard for pre-recorded, recordable and rewritable media, offering the best quality and features consumers could wish for themselves, at very low costs.

Second Generation

Although the CD was a very useful medium for the recording and distribution of audio and some modest data-applications, demand for a new medium offering higher storage capacities rose in the 90s. These demands lead to the evolution of the DVD specification and a five to ten fold increase in capacity. This enabled high quality, standard definition video distribution and recording. Furthermore, the increased capacity accommodated more demanding data applications. At the same time, the DVD spec used the same form factor as the CD, allowing for seamless migration to the next generation format and offering full backwards compatibility.

Third Generation
Now High Definition video is demanding a new solution. History proved that a significant five to ten time increase in storage capacity and the ability to play previous generation formats are key elements for a new format to succeed. This new format has arrived with the advent of Blu-ray Disc, the only format that offers a considerable increase in storage capacity with its 25 to 50 GB data capacity. This allows for the next big application of optical media: the distribution and recording of High Definition video in the highest possible quality. In fact, no other proposed format can offer the data capacity of Blu-ray Disc, and no other format will allow for the same high video quality and interactive features to create the ultimate user experience. As with DVD, the Blu-ray Disc format is based on the same, bare disc physical form factor, allowing for compatibility with CD and DVD. The Blu-ray Disc specification was officially announced in February 2002. Blu-ray Disc recorders were first launched in Japan in 2003.

Reply
project report helper
Active In SP
**

Posts: 2,270
Joined: Sep 2010
#10
19-10-2010, 11:10 AM


Blu-ray Technology

BIREFRINGENCE:-The property or capacity of splitting a beam of light into two beams, each refracted at a different angle, and each polarized at a right angle to the other. Certain crystals such as calcite and quartz have this property.

AACS:- The Advanced Access Content System (AACS) is a standard for content distribution and digital rights management, intended to restrict access to and copying of the next generation of optical discs and DVDs.

AES:-the Advanced Encryption Standard (AES) is a symmetric-key encryption standard adopted by the U.S. government

BD+ is a component of the Blu-ray Disc Digital Rights Management system. It was developed by Cryptography Research Inc.

AVCHD (Advanced Video Coding High Definition)[1] is a format for the recording and playback of high definition video.

High-bandwidth Digital Content Protection (HDCP) is a form of digital copy protection developed by Intel Corporation to prevent copying of digital audio and video content as it travels across DisplayPort, Digital Visual Interface (DVI), High-Definition Multimedia Interface (HDMI), Gigabit Video Interface (GVIF), or Unified Display Interface (UDI) connections.

# Universal Media Disc (UMD)

# Enhanced Versatile Disc (EVD)

# Forward Versatile Disc (FVD)

# Holographic Versatile Disc (HVD)

# China Blue High-definition Disc (CBHD)



High definition Versatile Multilayer Disc (HD VMD)



# Laserdisc (LD)

# Video Single Disc (VSD)

# Ultra Density Optical (UDO)

# Stacked Volumetric Optical Disk (SVOD)

# Five dimensional discs (5D DVD)

# Nintendo optical disc (NOD)

The Moving Picture Experts Group (MPEG) is a working group of experts that was formed by ISO and IEC to set standards for audio and video compression and transmission.It was established in 1988 and its first meeting was in May 1988 in Ottawa, Canada.

Video Coding Experts Group or Visual Coding Experts Group (VCEG)
Joint Photographic Experts Group is the joint committee between ISO/IEC JTC1 and ITU-T that created the JPEG, JPEG 2000, and JPEG XR standards.
Reply
seminar class
Active In SP
**

Posts: 5,361
Joined: Feb 2011
#11
07-03-2011, 12:13 PM


.docx   blue ray.docx (Size: 415.87 KB / Downloads: 70)
1. INTRODUCTION
Blu-ray Disc, or BD, is an optical disc that uses state-of-the-art blue-violet laser technology to enable consumers to record high-definition TV broadcasting. Developed by the "Blu-ray Disc Founders" group, these companies include Hitachi, LG, Matsushita, Pioneer, Philips, Samsung, Sharp, Sony, and Thomson. Although Blu-ray Disc was primarily designed to be a "consumer high definition video recording format", its very high storage capacities and high-speed data transfer rates also make Blu-ray Disc suitable for storage libraries and ultimately other applications.
A Blu-ray Disc has the same physical size as a DVD (12cm) but has higher data and track densities that give it between roughly three to six times the storage capacity of a standard 4.7GB DVD-R. This feat is made possible using a 405 nm (405 billionth of a meter) blue-violet laser, actually violet-purple, (see figure 1) and an optical pickup head with a 0.85 NA (numerical aperture) lens. Because a blue-violet light laser has a shorter wavelength (405 nm) than the red light (650 nm) used in CD and DVD systems, it allows the laser beam to make a smaller spot on the disc surface. With each bit of data taking up less space on the disc, more data can be stored on a 4.7-inch disc.
1st GENERATION:
Compact disc (CD): --- 650/700 MB
It is with us for over 20 years.
Wavelength of laser which reads data: 780 nm
Color of laser: Red
2nd GENERATION:
Digital versatile disc (DVD): --- 4.7 GB
It offers high quality sound and video than CD.
Wavelength of laser which reads data: 650 nm
Color of laser: Red
3rd GENERATION:
Blu-ray disc (BD): --- 25/50 GB
-Next generation optical disc format.
-Developed by blu-ray disc association (which includes Apple, Hitachi, HP, LG, Panasonic, Pioneer, Philips, Samsung, Sharp, Sony)
-Wavelength of laser which reads data: 405 nm
-Color of laser: Blue-violet
FORMAT OF BD:
It comes in four different formats:
• BD-ROM (read only) :for reading recorded content.
• BD-R (recordable) :for PC data storage.
• BD-RW (rewritable) :for PC data storage.
• BD-RE (rewritable) :for HDTV (high definition television) recording.
1.1. TYPES OF BLUE RAY DISC
1.1.1. SINGLE LAYER :

Can hold data up to 25/27 GB that means 2 hrs of HD video or about 13 hrs of standard video.
1.1.2. DOUBLE LAYER :
Can hold data up to 50 GB that means 4.5 hrs of HD video or more than 20 hrs of standard video.
2. BLU-RAY DISC RECORDING LAYER
A distinct feature of the Blu-ray Disc is the position of the recording layer within the disc. For DVD, the recording layer is sandwiched between two 0.6-mm thick layers of polycarbonate plastic. But the recording layer in a Blu-ray Disc sits near the surface of a 1.1-mm thick plastic substrate and is protected by a mere 0.1-mm thin cover layer. This not only allows for better disc readout, as the laser does not have to travel far to the point of focus, but serves to increase the recording density because the laser can be more narrowly focused by the larger 0.85 NA lens aperture (see figure 1 above). In addition, it minimizes tilt problems associated with substrate stresses which can occur during the injection molding process used to produce them. This can cause the laser light to split into two separate beams, refer to as birefringence, and if it becomes excessive, the drive cannot read data reliably from the disc.
But having the recording layer closer to the surface has its disadvantages as it leaves the disc exposed to accidental abrasions, dust, and fingerprint marks. To overcome this, a specially formulated protective hard-coat is applied on top of the cover layer. This protective coat is hard enough to prevent accidental abrasions and also allows for
1. WHY THE NEED FOR SO MUCH CAPACITY?
High-definition video (720p or 1080i) requires five times the recording capacity of standard definition video (480i). The actual HDTV transmission is based on a 19.4 Mbps (Mega bits per second) digital data stream but the maximum data transfer for DVD is about 10 Mbps. Thus, there’s simply not enough bandwidth to put an HDTV program on a recordable DVD format. To achieve the density necessary to put this amount of data on a single-sided 12 cm optical disc, the size of the spots burned into the disc need to be smaller. In addition, the high-definition video will need to undergo compression to be able to store this high-definition picture.
Video and Audio Codecs
The Blu-ray Disc format employs MPEG-2, Video Codec 9 (VC-1 based on the Windows Media 9 format), or H.264/MPEG-4 AVC video compression techniques in order to lower the data rate (i.e., use less digital data) of the high-definition video. The excellent efficiency of the latest MPEG-4 AVC and VC-1 codec allow image data to be compressed to about one-third the size achieved by MPEG-2 and replay of high quality digital images.
But regardless of the codec utilized, the idea is to compress enough to decrease the bit rate to data capacity levels while trying to preserve the high-definition picture quality to a reasonable standard. This allows the high-definition signal to be recorded without excessive compression, preserving the detail of the original high-definition picture. The audio formats for BD extend beyond the current DVD specifications to include every type of audio codec available. Though, at this writing, the more robust DTS Digital Surround had been selected as the audio technology of choice for Blu-ray Disc (BD).
Capacitieof blu-ray disc
Blu-ray Disc may have three single-sided single-layer structure capacities of 23.3GB, 25GB, 27GB, and three single-sided dual-layer structure capacities of 46.6GB, 50GB and 54GB (without flipping sides) compared to current DVDs which can hold between 4.7GB and 9.4GB of data. However, recent press announcements had circulated that a "Hybrid" disc was being proposed by the Blu-ray Disc Founders that would be comprised of a double-sided single-layer containing an 8.5GB capacity standard-definition and a 25GB capacity high-definition version.
Compatibility
Blu-ray Disc is a totally new and radical optical storage medium requiring retooling and or construction of new disc manufacturing and replication plants. Thus, Blu-ray Disc does not share compatibility with current DVD technologies.
Reply
seminar class
Active In SP
**

Posts: 5,361
Joined: Feb 2011
#12
07-03-2011, 04:12 PM

Presented by:
P.S.Bhima Raju
A.Ratna Sudheer


.doc   Blue-ray disc.doc (Size: 105.5 KB / Downloads: 53)
Blu-Ray Disc
ABSTRACT

Blu-ray, also known as Blu-ray Disc (BD) is the name of a next-generation optical disc format jointly developed by the Blu-ray Disc Association (BDA), a group of leading consumer electronics and PC companies (including Apple, Dell, Hitachi, HP, JVC, LG, Mitsubishi, Panasonic, Pioneer, Philips, Samsung, Sharp, Sony, TDK and Thomson). The format was developed to enable recording, rewriting and playback of high-definition video (HD), as well as storing large amounts of data. A single-layer Blu-ray Disc can hold 25GB, which can be used to record over 2 hours of HDTV or more than 13 hours of standard-definition TV. There are also dual-layer versions of the discs that can hold 50GB.
While current optical disc technologies such as DVD, DVD±R, DVD±RW, and DVD-RAM use a red laser to read and write data, the new format uses a blue-violet laser instead, hence the name Blu-ray. Despite the different type of lasers used, Blu-ray products can easily be made backwards compatible through the use of a BD/DVD/CD compatible optical pickup and allow playback of CDs and DVDs. The benefit of using a blue-violet laser (405nm) is that it has a shorter wavelength than a red laser (650nm), which makes it possible to focus the laser spot with even greater precision. This allows data to be packed more tightly and stored in less space, so it's possible to fit more data on the disc even though it's the same size as a CD/DVD. This together with the change of numerical aperture to 0.85 is what enables Blu-ray Discs to hold 25GB/50GB.
With the rapid growth of HDTV, the consumer demand for recording HD programming is quickly rising. Blu-ray was designed with this application in mind and supports direct recording of the MPEG-2 TS (Transport Stream) used by digital broadcasts, which makes it highly compatible with global standards for digital TV. This means that HDTV broadcasts can be recorded directly to the disc without any quality loss or extra processing. To handle the increased amount of data required for HD, Blu-ray employs a 36Mbps data transfer rate, which is more than enough to record and playback HDTV while maintaining the original picture quality. In addition, by fully utilizing an optical disc's random accessing features, it's possible to playback video on a disc while simultaneously recording HD video.
Introduction:
In 1997, a new technology emerged that brought digital sound and video into homes all over the world. It was called DVD, and it revolutionized the movie industry.
The industry is set for yet another revolution with the introduction of Blu-ray Discs (BD). With their high storage capacity, Blu-ray discs can hold and playback large quantities of high-definition video and audio, as well as photos, data and other digital content.
What is Blu-ray disc?
A current, single-sided, standard DVD can hold 4.7 GB (gigabytes) of information. That's about the size of an average two-hour, standard-definition movie with a few extra features. But a high-definition movie, which has a much clearer image , takes up about five times more bandwidth and therefore requires a disc with about five times more storage. As TV sets and movie studios make the move to high definition, consumers are going to need playback systems with a lot more storage capacity.
Blu-ray is the next-generation digital video disc. It can record, store and play back high-definition video and digital audio, as well as computer data. The advantage to Blu-ray is the sheer amount of information it can hold:
• A single-layer Blu-ray disc, which is roughly the same size as a DVD, can hold up to 27 GB of data -- that's more than two hours of high-definition video or about 13 hours of standard video.
• A double-layer Blu-ray disc can store up to 54 GB, enough to hold about 4.5 hours of high-definition video or more than 20 hours of standard video. And there are even plans in the works to develop a disc with twice that amount of storage.
Building a Blu-ray:
The Blu-ray disc overcomes DVD-reading issues by placing the data on top of a 1.1-mm-thick polycarbonate layer. Having the data on top prevents birefringence and therefore prevents readability problems. And, with the recording layer sitting closer to the objective lens of the reading mechanism, the problem of disc tilt is virtually eliminated. Because the data is closer to the surface, a hard coating is placed on the outside of the disc to protect it from scratches and fingerprints.
The design of the Blu-ray discs saves on manufacturing costs. Traditional DVDs are built by injection molding the two 0.6-mm discs between which the recording layer is sandwiched. The process must be done very carefully to prevent birefringence.
1. The two discs are molded.
2. The recording layer is added to one of the discs.
3. The two discs are glued together.
Blu-ray discs only do the injection-molding process on a single 1.1-mm disc, which reduces cost. That savings balances out the cost of adding the protective layer, so the end price is no more than the price of a regular DVD.
Blu-ray has a higher data transfer rate -- 36 Mbps (megabits per second) -- than today's DVDs, which transfer at 10 Mbps. A Blu-ray disc can record 25 GB of material in just over an half an hour of time
How do Blu-ray formats work?
Discs store digitally encoded video and audio information in pits -- spiral grooves that run from the center of the disc to its edges. A laser reads the other side of these pits -- the bumps -- to play the movie or program that is stored on the DVD. The more data that is contained on a disc, the smaller and more closely packed the pits must be. The smaller the pits (and therefore the bumps), the more precise the reading laser must be.
Unlike current DVDs, which use a red laser to read and write data, both Blu-ray and HD-DVD use a blue laser. A blue laser has a shorter wavelength (405 nanometers) than a red laser (650 nanometers). The smaller beam focuses more precisely, enabling it to read information recorded in smaller pits. Blu-ray discs and HD-DVDs can both read pits that are much smaller than the pits on a DVD. That's pretty much where the similarity ends.
The recording layer on Blu-ray and HD-DVD differs. Whereas the HD-DVD recording layer is sandwiched between two 0.6 mm layers of polycarbonate plastic -- much like the recording layer on today's DVD -- Blu-ray places the data on top of a 1.1-mm-thick polycarbonate layer. The smaller pits, smaller beam and closer recording layer together enable a single-layer Blu-ray disc to hold more than 25 GB of information -- about five times the amount of information that can be stored on today's DVD and about twice that of an HD-DVD.
When will Blu-ray be available ?
Blu-ray recorders are already available in Japan, where more consumers have access to HDTV than in the United States. Outside of Japan, once more TV sets come equipped with a high-definition tuner, and more films and television shows are produced in high-definition (which is expected to happen by late 2005 or 2006), Blu-ray movies and TV shows on disc should become widely available; but the format is already available for home recording, professional recording and data storage. HD-DVD is expected to arrive in stores at the end of 2005.
Even when the new video standard begins to replace current technologies, consumers won't have to throw away their DVDs; but they may need to invest in a new player, depending upon which format they choose. HD-DVD will work on today's standard DVD players, while a straight Blu-ray will not. JVC has developed a Blu-ray hybrid disc that pairs a Blu-ray disc with a standard DVD -- this type of hybrid disc will survive the format transition. In any event, the Blu-ray coalition is planning to market backward-compatible drives with both blue and red lasers, which will be able to play traditional DVDs and CDs as well as Blu-ray discs.
What will each format mean for consumers? Blu-ray is billing itself as more high-tech, offering greater storage and capabilities, while HD-DVD is boasting lower costs and a less radical departure from the DVDs we already know and love. Comparing it to the old VHS-Betamax battle, HD-DVD looks more like VHS, and Blu-ray like Betamax. But at this point, industry insiders say the format war could go either way.
Ultimately, which format prevails will have a lot to do with its backers. HD-DVD has the DVD Forum behind it: a consortium of 230 consumer-electronics and entertainment companies, as well as movie studios New Line, Paramount, Universal and Warner Bros. Plus, Microsoft plans to support HD-DVD with its next Windows operating system, code-named Longhorn. Blu-ray has more than 10 of the top electronics companies behind it, plus the support of Columbia TriStar, Disney and MGM studios. Also, it has been rumored that the new PlayStation 3 game system will support Blu-ray.
Reply
seminar class
Active In SP
**

Posts: 5,361
Joined: Feb 2011
#13
21-03-2011, 04:06 PM


.ppt   blu-ray DISC.ppt (Size: 245 KB / Downloads: 77)
BLU –RAY DISC
 The “Blu-Ray Disc association” was found in 2002 by nine leading electronic companies.
 Blu-ray disc is the next generation optical disc format.
 BD uses a blue-violet laser operating at a wavelength of 405 nm, to read and write.
 A single layer Blu-Ray Disc can store 25GB. In dual layer can store 50GB.
 In fact ,7 0f 8 movie studios are supporting the Blu-ray format and 5 of them are releasing their movies in Blu-ray disc.
FASTNESS IN READ/WRITE ON A BD
 BD-ROM movies will require a 54Mbps data transfer rate the minimum speed were expecting to see is 2x.
 The large NA (numerical aperture) value effectively means that Blu-ray will require less recording power and lower disc rotation speed than DVD and HD-DVD.
 Blu-ray disc association (BDA) already has plans to raise the speed to 8x(288Mbps) or more in the future.
CODECS IN BLU-RAY DISC
 Codecs are compression schemes
 Reduces the data storage requirements
 video codecs are required to support:
MPEG-2
H.264/AVC
SMPTE VC-1
 Audio codecs are required to support:
Dolby Digital AC-3
DTS
linear PCM
DIGITAL RIGHT MANAGEMENT
 The Blu-ray disc format employs several layers of DRM.
 BD+ is a small virtual machine embedded in authorized players.
 It allows content providers to include executable programs on Blu-ray Discs.
 BD-ROM mark is a small amount of cryptographical data that is stored physically different from normal blu-ray data.
HARD-COATING TECHNOLOGY
 Blu-ray discs use a layer of protective material on the surface through which the data is read.
 The introduction of polymer coating in blu-ray discs substantial scratch resistance.
 Verbatim recordable and rewritable blu-ray discs use their own proprietary hard-coat technology called ScratchGuard.
COMPATIBILITY
 Blu-ray disc drives should be capable of reading standard DVDs for backward compatibility.
 Blu-ray disc players released support DVD playback as well, however not all support CD playback.
BLU-RAY DISC COMPARISON WITH HD DVD, AND DVD
 Laser wavelength
 Storage capacity
 Numerical aperture
 Maximum bit rate
 Video resolution (maximum)
 Internet support
 Secondary video decoder
 Secondary audio decoder
 Audio codecs
 Video codecs
APPLICATIONS
 High definition Television Recording
 High definition video distribution
 High definition Camcorder Archiving
BLU-RAY DISC DEVELOPMENT
 Quad-layer(100 GB) discs have been demonstrated on a drive with modified optics.
 JVC has developed a three layer technology that allows putting both standard-definition DVD data and HD data on a BD/DVD combo.
CONCLUSION
 Thus the blu-ray disc provides greater video, audio quality, and special features.
 The advanced interactivity combined with the networking features of blu-ray will also allow content producers to support new innovative features such as downloading extras, updating content via the web, and watching live broadcasts of special features.
Reply
seminar class
Active In SP
**

Posts: 5,361
Joined: Feb 2011
#14
23-03-2011, 03:28 PM

PRESENTED BY
PUSPAK RANJAN AGASTI


.ppt   blu-ray disc.ppt (Size: 83.5 KB / Downloads: 57)
INTRODUCTION
Blu-ray, also known as Blu-ray Disc (BD) is the name of a next-generation optical disc format. The format was developed to enable recording, rewriting and playback of high-definition video (HD), as well as storing large amounts of data.
The format offers more than five times the storage capacity of traditional DVDs and can hold up to 25GB on a single-layer disc and 50GB on a dual-layer disc.

Reply
seminar class
Active In SP
**

Posts: 5,361
Joined: Feb 2011
#15
12-05-2011, 12:19 PM


.doc   blu ray1.doc (Size: 1,010.5 KB / Downloads: 61)
Blu-ray Disc (official abbreviation BD) is an optical disc storage medium designed to supersede the DVD format. The standard physical medium is a 12 cm plastic optical disc, the same size as DVDs and CDs. Blu-ray Discs contain 25 GB per layer, with dual layer discs (50 GB) the norm for feature-length video discs and additional layers possible in the future.
The first Blu-ray Disc prototypes were unveiled in October 2000, and the first prototype player was released in April 2003 in Japan. After that, it continued to be developed until its official release in June 2006.
The name Blu-ray Disc refers to the blue laser used to read the disc, which allows information to be stored at a greater density than is possible with the longer-wavelength red laser used for DVDs.
Blu-ray Disc was developed by the Blu-ray Disc Association, a group representing makers of consumer electronics, computer hardware, and motion pictures. As of June 2009, more than 1,500 Blu-ray Disc titles were available in Australia and the United Kingdom, with 2,500 in the United States and Canada. In Japan, as of July 2010, more than 3,300 titles have been released.
During the high definition optical disc format war, Blu-ray Disc competed with the HD DVD format. Toshiba, the main company that supported HD DVD, conceded in February 2008,[4] releasing their own Blu-ray Disc player in late 2009.
History
In 1992, the Japanese inventor Shuji Nakamura invented the first efficient blue LED, and four years later, the first blue laser. Nakamura used the material deposited on sapphire substrate, although the number of defects remained very high (10^6-10^10/cm2). The presence of defects in the structure of the laser made it difficult in a very important way to build a high-powered laser. In the early 90s at the Institute of High Pressure Physics PAS in Warsaw, under the leadership of Dr. Sylwester Porowski was developed technology of gallium nitride crystals with very high structural quality - number of defects did not exceed 100/cm2 it was at least 10 000 times less than the best material deposition on sapphire. In 1999, Shuji Nakamura invented the crystal used to investigate the effects of defects on the properties of lasers. Lasers built on Polish crystal has repeatedly proved to be better than previously constructed, both in terms of life span and performance. The lifetime of the power of 30 mW has increased 10-fold (from 300 to 3 000 hours), and the yield more than double. A further comprehensive development of technologies taking off from sapphire substrates led to the launch of the first mass production of the device, which uses blue lasers. After 10 years of controlled production in Japan, blue laser power of 60mW was achieved. Nakamura's technological successes have created the basis for a new field of lighting and progress in the electronics industry. Nakamura was awarded the 2006 Millennium Technology Prize Award, often called the Nobel Prize of technological achievements.
A blank rewritable Blu-ray Disc (BD-RE).
Origins

Sony started two project and implimentations applying the new diodes: UDO (Ultra Density Optical), and DVR Blue (together with Pioneer), a format of rewritable discs that would eventually become Blu-ray Disc (more specifically, BD-RE). The core technologies of the formats are similar.
The first DVR Blue prototypes were unveiled at the CEATEC exhibition in October 2000 by Sony. A trademark for the "Blue Disc" logo was filed February 9, 2001. On February 19, 2002, the project and implimentation was officially announced as Blu-ray Disc and Blu-ray Disc Founders was founded by the nine initial members.
The first consumer device arrived in stores on April 10, 2003: the Sony BDZ-S77, a US$3,800 BD-RE recorder that was made available only in Japan. But there was no standard for prerecorded video, and no movies were released for this player.
Hollywood studios insisted that players be equipped with Digital Rights Management before they would release movies for the new format, and they wanted a new DRM system that would be more secure than the failed Content Scramble System (CSS) used on DVDs.
On October 4, 2004, the name "Blu-ray Disc Founders" was officially changed to the Blu-ray Disc Association (BDA), and 20th Century Fox joined the BDA's Board of Directors.
The Blu-ray Disc physical specifications were completed in 2004.
In January 2005, TDK announced that they had developed a hard coating polymer for Blu-ray Discs. Cartridges, originally used for scratch protection, were no longer necessary and were scrapped.
The BD-ROM specifications were finalized in early 2006.
AACS LA, a consortium founded in 2004, had been developing the DRM platform that could be used to securely distribute movies to consumers. However, the final AACS standard was delayed, and then delayed again when an important member of the Blu-ray Disc group voiced concerns. At the request of the initial hardware manufacturers, including Toshiba, Pioneer, and Samsung, an interim standard was published that did not include some features, such as managed copy.
Launch and sales developments
The first BD-ROM players (e.g. Sony BDP-S1) were shipped in mid-June 2006, though HD DVD players beat them to market by a few months.
The first Blu-ray Disc titles were released on June 20, 2006: 50 First Dates, The Fifth Element, Hitch, House of Flying Daggers, Underworld: Evolution, xXx (all Sony), and MGM's The Terminator. The earliest releases used MPEG-2 video compression, the same method used on standard DVDs. The first releases using the newer VC-1 and AVC codecs were introduced in September 2006. The first movies using 50 GB dual-layer discs were introduced in October 2006. The first audio-only release was made in March 2008.
The first mass-market Blu-ray Disc rewritable drive for the PC was the BWU-100A, released by Sony on July 18, 2006. It recorded both single and dual-layer BD-Rs as well as BD-REs and had a suggested retail price of US $699.
Reply

Important Note..!

If you are not satisfied with above reply ,..Please

ASK HERE

So that we will collect data for you and will made reply to the request....OR try below "QUICK REPLY" box to add a reply to this page

Quick Reply
Message
Type your reply to this message here.


Image Verification
Please enter the text contained within the image into the text box below it. This process is used to prevent automated spam bots.
Image Verification
(case insensitive)

Possibly Related Threads...
Thread Author Replies Views Last Post
  Development of Smart Antenna Technology project uploader 1 716 07-04-2016, 11:24 AM
Last Post: mkaasees
  AN OVERVIEW OF SMART ANTENNA TECHNOLOGY FOR MOBILE COMMUNICATIONS SYSTEMS seminar addict 3 1,536 07-04-2016, 11:24 AM
Last Post: mkaasees
  IRIS Recognition Technology ppt seminar ideas 1 673 06-04-2016, 03:23 PM
Last Post: mkaasees
  flexible display technology ppt jaseelati 0 594 24-01-2015, 04:26 PM
Last Post: jaseelati
  iden technology ppt jaseelati 0 357 23-01-2015, 02:27 PM
Last Post: jaseelati
  6g mobile technology pdf jaseelati 0 345 22-01-2015, 02:00 PM
Last Post: jaseelati
  valvetronic engine technology powerpoint jaseelati 0 323 15-01-2015, 02:46 PM
Last Post: jaseelati
  optical technology in current measurement jaseelati 0 308 10-01-2015, 01:19 PM
Last Post: jaseelati
  seminar on wifi technology pdf jaseelati 0 336 07-01-2015, 01:45 PM
Last Post: jaseelati
  6g technology ppt jaseelati 0 338 27-12-2014, 03:26 PM
Last Post: jaseelati