What are Blu-ray Discs?

What is a Blu-ray Disc? How is it different from HD DVD's? Lets see it in detail, the Technology used and the properties of a typical Blu-ray disc.

Blu-ray Disc (also known as Blu-ray or BD) is an optical disc storage medium, developed by the Blu-ray Disc Association, a group representing makers of consumer electronics, computer hardware, and motion pictures. Its main uses are high-definition video and data storage. This disc has the same physical dimensions as standard DVDs and CDs.

The name Blu-ray Disc is derived from the blue laser (violet-colored) used to read and write to this type of disc. In part because of the shorter wavelength (405 nanometres), substantially more data can be stored on a Blu-ray Disc than on a DVD, which uses a red (650 nm) laser. A dual-layer Blu-ray Disc can store 50 gigabytes, almost six times the capacity of a dual-layer DVD (8 gigabytes), or ten and a half times that of a single-layer DVD(4.7 gigabytes).

Technical Specifications :

Media type : High-density optical disc
Encoding : MPEG-2, H.264/MPEG-4 AVC, and VC-1
Capacity : 25 GB (single layer) ; 50 GB (dual layer)
Block size : 64kb ECC
Read : 405 nm laser
Mechanism :
* 1× at 36 Mbit/s (4.5 Mbyte/s)
* 2× at 72 Mbit/s (9 Mbyte/s)
* 4× at 144 Mbit/s (18 Mbyte/s)
* 6× at 216 Mbit/s[1] (27 Mbyte/s)
* 8× at 288 Mbit/s (36 Mbyte/s)
* 12× at 432 Mbit/s (54 Mbyte/s)
Developed by : Blu-ray Disc Association
Usage :
* Data storage
* High-definition video
* High-definition audio
* PlayStation 3 games

High-definition video may be stored on Blu-ray ROM discs with up to 1920x1080 pixel resolution at up to 60 frames per second interlaced or 24 frames per second progressive.

Writing Speed :

On August 8, 2008, Japanese electronics company Buffalo announced that it will ship the first 8x Blu-ray burners in Japan starting from September 2008. On September 22, 2008, Buffalo announced one internal and one external 8x Blu-ray burners for the United States, to be released the same month. The following day Sony announced the BWU-300S, an internal 8x Blu-ray burner for the United States.

Most of the Film Making Companies in Hollywood are making using of Blu-ray Discs.The usage of Blu-ray Disc had reached 60% of U.S. households.The Dar Knight Blu-ray Disc sold 600,000 copies on the first day of its launch in the United States, Canada, and United Kingdom.A week after launch the The Dark Knight Blu-ray Disc had sold over 1.7 million copies worldwide making it the first Blu-ray Disc title to sell over a million copies in the first week of release.

As of December 21, 2008, more than 890 Blu-ray disc titles are available in Australia, more than 720 Blu-ray Disc titles are available in Japan, more than 1,140 Blu-ray Disc titles are available in the United Kingdom, and more than 1,220 Blu-ray Disc titles are available in the United States.

When do they come to INDIA? Is it the Recession or our Market, delaying the Entry of these Discs.