What is Blu-Ray?

Blu-Ray is an optical storage format developed by Sony and Phillips. Blu-Ray was created to store large amounts of high definition video and sound. Blu-Ray gets its name from the type of laser it uses to read and write data from and to the disc, the color of the laser is a hue of blue-violet. Due to the extreme density of these optical discs the data needs to be smaller to fit onto the disc, a blue-violet laser has a shorter wavelength than the normal red lasers used today.

Blu-Ray technology is so-named because of its use of blue laser technology in storing and reading data. Being on the shorter wavelength end of the light spectrum than the red laser used for DVD and CD technologies (405 nanometer for Blu-Ray versus 650 nanometer and 780 nanometer for DVD and CD technology), blue laser is capable of storing a much larger amount of data using the same space because of a much smaller "spot size" requirement. Blu-Ray's 405nm wavelength blue-violet laser uses an 0.85nm pickup aperture.

Single-layer Blu-Ray disks currently store 23.3GB of data, which dual-layer Blu-Ray disks are able to store 46.6GB of data.

There is currently a market war taking place against both HD DVD's and Blu-Ray DVD's. These two types of DVD's are fighting to see who will be the new form of media for the years to come. As of yet, neither media type has made enough inroads to garner a champion.

Obviously the major benefit of Blu-Ray DVD's is that it is able to hold more data on one disc, therefore allowing high definition audio and video. The more data you have, the more data can be read to give a clearer picture with more color and vividness.

One of the benefits of Blu-Ray technology is that because data is so close together, early types of Blu-Ray discs would be contaminated by slight scratches. However, a new coating has been developed that makes Blu-Ray discs extremely difficult to scratch.

Blu-Ray is looking to make inroads into the consumer electronics market with the Blu-Ray DVD player with its Sony PlayStation. The Sony PlayStation will include a basic Blu-Ray DVD player which might spur sales of media and make it the de facto standard.

The disadvantages to Blu-Ray discs are that they are quite expensive. For instance, players are selling at about the $1,000 mark and DVD discs will be more expensive than their standard DVD counterparts. Another disadvantage is that since there are two standards, both Blu-Ray and HD, most people are sitting on the sidelines to see who the winner is. Because Blu-Ray has been developed in part with Sony, Sony has included DRM or digital rights management that will make it more difficult for people to place shift and time shift their content.

Blu-Ray Technology

BD Formats

There are three formats being developed for Blu-Ray technology. The BD-ROM or Blu-Ray read-only disc format will be used to store movies, computer games and software. The Blu-Ray recordable or BD-R will provide users the opportunity to store larger amounts of data and HDTV recordings in one disc. The BD-RE or Blu-Ray rewritable disc format will provide users the ability to change the disc's contents.

Disc Capacity

The main advantage of Blu-Ray technology is its capability of storing massive amounts of data in one disc. Blu-Ray technology will enable users to store an average of 25GB-27GB worth of data into just one layer. This is equivalent to 4 hours worth of HD video and audio. Moreover, Blu-Ray dual layer discs will have a storage capacity of up to 54GB. Research on Blu-Ray discs with up to four layers and with storage capacities of up to 200 GB is currently underway.

Supportable File Formats

Blu-Ray discs are capable of supporting different file formats such as MPEG-2, MPEG-4 High Profile AVC and VC-1 coder decoders which enables the discs to store up to four hours worth of HDTV audio-video per layer. It is also capable of supporting the different multi-channel audio file formats such as the different file formats of Dolby and DTS as well as PCM audio file formats. BD rewritable and recordable disc formats will also be backwards-compatible with older formats such as MPEG-2 while newer codecs will enable Blu-Ray technology to support new file formats in the future. The integration of Java cross platform will also enable the Blu-Ray disc to have interactive menus as well as the capability to add new content or updates such as new subtitles through the Internet.

Regional Codes and Security

For security, Blu-Ray supports mandatory HDCP encrypted output, ROM-Mark watermarking, BD+ dynamic cryptology, and the Advanced Access Content System (AACS).

Blu-Ray discs will have three regional codes: one for countries in the Amercian continent as well as countries in east Asia except China and Japan, another for countries in the European and African continents and another one for all the other countries in the Asian continent such as China, Russia, etc.

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