Large-Capacity Optical Disc Video Recording Format Established

TOKYO, Feb. 20 -- Nine companies have jointly established the basic specifications for a next-generation large-capacity optical disc video recording format called "Blu-ray Disc." The Blu-ray Disc enables the recording, rewriting and play back of up to 27 gigabytes of data on a single-sided single layer, 12-cm CD/DVD-size disc using a 405-nm blue-violet laser.

The companies that established the basic specifications for the Blu-ray Disc are: Hitachi Ltd., LG Electronics Inc., Matsushita Electric Industrial Co. Ltd., Pioneer Corp., Royal Philips Electronics, Samsung Electronics Co. Ltd., Sharp Corp., Sony Corp. and Thomson Multimedia.

By employing a short-wavelength blue-violet laser, the format successfully minimizes its beam spot size by making the numerical aperture on a field lens that converges the laser 0.85. In addition, by using a disc structure with a 0.1 mm optical transmittance protection layer, the Blu-ray Disc diminishes aberration caused by disc tilt.