A Blu-ray disk (BD) is a high-capacity optical disk medium developed for recording, rewriting and playing back high definition video. It can store large amounts of data and was designed to supersede the DVD.
Blu-ray was jointly developed by a group of personal computer and consumer electronics companies called the Blu-ray Disc Association. Blu-ray disks support higher resolutions and more advanced video and audio formats compared to DVDs.
The information density of the DVD format was limited by the wavelength of the laser diodes used. Following protracted development, blue laser diodes operating at 405 nanometers became available on a production basis, allowing for the development of a more-dense storage format that could hold higher-definition media. Sony started two projects in collaboration with Philips
Blu-ray technology gets its name from the blue-violet laser that is used to read Blu-ray disks. Compared to a DVD’s red laser, a blue laser permits more information to be stored at a greater density. For example, while a DVD can store 15 GB per layer, a Blu-ray disc can store 25 GB per layer, and dual-layer disks can hold up to 50 GB.
Compared to a DVD, Blu-ray also provides much higher resolution; while a DVD with standard definition can provide a definition of 720×480 pixels, Blu-ray high definition has 1920X1080 pixel resolution.
Blu-ray is currently supported by about 200 of the world’s leading consumer electronics, personal computer, recording media, video game and music companies. The format also has support from all Hollywood studios and countless smaller studios as a successor to today’s DVD format. Many studios have also announced that they will begin releasing new feature films on Blu-ray Disc day-and-date with DVD, as well as a continuous slate of catalog titles every month. For more information about Blu-ray movies