What is a blue ray disk?What is the difference between a DVD and a Blue Ray disk?

Question

Also tell me what,s special in a blue ray disc.Plz

Answer 1

you can fit about 4 times as much info on a blue ray disk

Answer 2

Physically, there is nothing different between a DVD and Blu-Ray disc. It's all in the laser that is reading the disc. A Blu-Ray player uses a laser in the "blue" wavelength which is a much narrower beam and thus has a narrower track on the disc which allows more data to be written to the disc. Therefore a larger video format/resolution can be written to a Blu-Ray disc than a DVD. Also, they can include more extras (and previews).

Answer 3

Blue Ray Disk is the more advanced DVD nowadays. Has faster speed & large data capacity

Answer 4

If you remember some high school physics you'll remember that blue light has a smaller wavelength than red. Since a red laser reads current gen DVDs they have to write the tracks thicker than they would if a blue laser did the reading and writing.
Bottom line- more space more than 50GB if dual layer. Blu ray and HD have about the same blue laser tech, however I think Blu ray will win out.

Answer 5

the classic dvd uses a red laser, vs the blue laser in the blue ray discs. Since blue has a shorter wavelength than red, more information can be stored on a disc created and read by a blue ray.

Answer 6

Actually it is Blu-ray. Its has a larger capacity than DVD.It uses blue laser instead of red laser like the one used in DVD. The special about it is it has more capacity in same size as DVD disc.Blu-ray has shorter wavelength. that means it is easier to focus the ray onto a disc.

Answer 7

The name Blu-ray is derived from the blue-violet laser used to read and write this type of disc. Because of this shorter wavelength (405 nm), substantially more data can be stored on a Blu-ray Disc than on the common DVD format, which uses a red, 650 nm laser. In comparison to HD DVD, which also uses a blue laser, Blu-ray Disc has more information capacity per layer (currently 25 GB, but test media is up to 33 GB). However, Blu-Ray discs are expected to be more expensive than HD DVD discs, at least initially. Sony has released 50 GB recordable BDs and will soon be releasing 50 GB rewritable discs.

The Blu-ray Disc is a similar format to PDD, another optical disc format developed by Sony (which has been available since 2004) but offering higher data transfer speeds. PDD was not intended for home video use and was aimed at business data archiving and backup, although currently it is gaining popularity as an HD video format medium and PlayStation 3 medium. The UDO format is aimed at similar purposes. Blu-ray is currently embroiled in a bitter format war against the HD DVD disc.


The Blu-ray Disc system uses a blue-violet laser operating at a wavelength of 405 nm, similar to the one used for HD DVD, to read and write data. Conventional DVDs and CDs use red and infrared lasers at 650 nm and 780 nm respectively.

In the early 1990s two high-density optical storage standards were being developed: one was the MultiMedia Compact Disc (MMCD), backed by Philips and Sony, and the other was the Super Density disc (SD), supported by Toshiba, Time-Warner, Matsushita Electric, Hitachi, Mitsubishi Electric, Pioneer, Thomson, and JVC. IBM's president, Lou Gerstner, acting as a matchmaker, led an effort to unite the two camps behind a single standard, anticipating a repeat of the costly format war between VHS and Betamax in the 1980s.

Philips and Sony abandoned their MMCD format (not to be confused with MultiMediaCards) and agreed upon Toshiba's SD format (not to be confused with secure digital cards, although the logo for the SD disc format would be re-used for the SD digital card format) with two modifications that are both related to the servo tracking technology. The first one was the adoption of a pit geometry that allows "push-pull" tracking, a proprietary Philips/Sony technology. The second modification was the adoption of Philips' EFMPlus. EFMPlus, created by Kees Immink, who also designed EFM, is 6% less efficient than Toshiba's SD code, which resulted in a capacity of 4.7 GB as opposed to SD's original 5 GB. The great advantage of EFMPlus is its great resilience against disc damage such as scratches and fingerprints. The result was the DVD specification Version 1.5, announced in 1995 and finalized in September 1996. In May 1997, the DVD Consortium was replaced by the DVD Forum, which is open to all companies.

"DVD" was originally an initialism for "Digital Video Disc." [citation needed] Some members of the DVD Forum believe that it should stand for "Digital Versatile Disc" to reflect its widespread use for non-video applications. Toshiba, which maintains the official DVD Forum site [1], adheres to the latter interpretation, and indeed this appeared within the copyright warnings on some of the earliest examples. However, the DVD Forum never reached a consensus on the matter, and so today the official name of the format is simply "DVD"; the letters do not officially stand for anything.

Answer 8

The classic dvd uses a red laser, The blue laser in the blu-ray discs. AND ITS CALLED BLU-RAY!!!???!!!

Answer 9

Bluray disk is a high-density optical disc format for the storage of digital media, including high-definition video.
The Blu-Ray disc is one that can be 25gb or 50gb, which means it creates a wonderful amount of room for videogame designers to work with.
* 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 double-layer disc even extends these numbers up to 3 hours in HD quality and 9 hours of SD bonus material.


Physical size Single layer capacity Dual layer capacity
12 cm, single sided 25 GB (23.3GiB) 50 GB (46.6GiB)
12 cm, double sided 50 GB (46.6GiB) 100 GB (93.2GiB)
8 cm, single sided 7.8 GB (7.3GiB) 15.6 GB (14.5GiB)
8 cm, double sided 15.6 GB (14.5GiB) 31.2 GB (29GiB)

[edit] Laser and optics

The Blu-ray Disc system uses a blue-violet laser operating at a wavelength of 405 nm, similar to the one used for HD DVD, to read and write data. Conventional DVDs and CDs use red and infrared lasers at 650 nm and 780 nm respectively.

[edit] 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 consortium worried that such an inconvenience would hurt Blu-ray Disc's market adoption.[1] Blu-ray Discs now use a layer of protective material on the surface through which the data is read.

Both Sony and Panasonic replication methods include proprietary hard-coat technologies. Sony's rewritable media are sprayed with a scratch-resistant and antistatic coating.[2]

TDK also announced a way to remedy the problem in January 2004 with the introduction of a clear polymer coating that gives Blu-ray Discs substantial scratch resistance. The coating was developed by TDK and is called "Durabis". It allows BDs to be cleaned safely with only a tissue. The coating is said to successfully resist "wire wool scrubbing" according to Samsung Optical technical manager Chas Kalsi. It is not clear, however, whether discs will use the Durabis coating or if the use of the coating will prove too expensive.

Verbatim announced in July 2006 that their Blu-ray Disc recordable and rewritable discs would incorporate their hard-coat ScratchGuard technology which protects against scratches, abrasion, fingerprints, and traces of grease.[3][4]

[edit] Ongoing Development

Although the Blu-ray specification has been finalized, engineers continue working to advance the technology. Quad-layer (100 GB) discs have been demonstrated. And TDK recently announced that they have created a working experimental Blu-ray Disc capable of holding 200 GB of data on a single side, using six 33 GB data layers.[5] Such discs would almost certainly not work on today's Blu-ray players, as these devices are only designed and tested on discs that meet the current specification. Of course, six-layer discs or other advanced techniques may be included in a later generation of the Blu-ray spec, if they can be reliably mass-produced.

Answer 10

go to http://wikipedia.org it will tell you all that you need to know