What is blu-ray?
Blu-ray is a next generation video disc format that enables the ultimate high definition entertainment experience. Blu-ray Discs bring your favorite movies to life with crystal clear picture and rich beautiful surround sound. They hold 5x more information than DVD and offer an exciting array of advanced interactive features and bonus content. The discs are highly resistant to dirt and scratches and will play on a wide range of Blu-ray Disc players.
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 , 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.
Blu-ray Disc was developed by the Blu-ray Disc Association, a group of companies representing consumer electronics, computer hardware, and motion picture production. The standard is covered by several patents belonging to different companies. As of April 2008, a joint licensing agreement for all the relevant patents had not yet been finalized.
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.
While current optical disc technologies such as DVD, DVD±R, DVD±RW, and DVD-RAM rely on 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 with CDs and DVDs through the use of a BD/DVD/CD compatible optical pickup unit. 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.
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.
