Definition of Blu-ray

Blu-ray Disc: Cf. Wikipedia, the free encyclopedia.

Blu-ray Disc

Blu-ray Disc (also known as Blu-ray or BD) is an optical disc storage media format. Its main uses are high-definition video and data storage. The disc has the same dimensions as a standard DVD or CD.

The name Blu-ray Disc is derived from the blue-violet laser used to read and write this type of disc. Because of its shorter wavelength (405 nm), substantially more data can be stored on a Blu-ray Disc than on the DVD format, which uses a red (650 nm) laser. A Dual Layer Blu-ray Disc can store 50 GB, almost six times the capacity of a dual layer DVD.

Blu-ray 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 March 2007, a joint licensing agreement for all the relevant patents had not yet been finalized.

As of February 19, 2008, more than 450 Blu-ray Disc titles have been released in the United States, and more than 250 in Japan.

Blu-ray was locked in a format war against HD DVD until the format emerged as the winner on February 19, 2008 when Toshiba — the main driving force behind HD DVD — announced it would no longer develop, manufacture and market HD DVD players and recorders. Some analysts believe that Sony's PlayStation 3 video game console played an important role in the format war, believing it acted as a catalyst for Blu-ray Disc, as the PlayStation 3 used a Blu-ray disc drive as its primary source of media-reading technology. They also credited Sony's more thorough and influential marketing campaign. It must also be noted, that Blu-ray players can reproduce AVCHD content, recorded by modern high definition camcorders, while HD DVD could not.