The following Nine leading companies have jointly established the basic specifications for a next generation large capacity optical disc video recording format called Blu-ray Disc.  Hitachi, Ltd.,LG Electronics Inc., Matsushita Electric Industrial Co., Ltd., Pioneer Corporation, Royal Philips Electronics, Samsung Electronics Co., Ltd.,Sharp Corporation, Sony Corporation, Thomson Multimedia

The Blu-ray Disc enables the recording, rewriting and play back of up to 27 gigabytes (GB) of data on a single sided single layer 12cm CD/DVD size disc using a 405nm blue-violet laser. 

By employing a short wavelength blue violet laser, the Blu-ray Disc successfully minimizes its beam spot size by making the numerical aperture (NA) on a field lens that converges the laser 0.85.  In addition, by using a disc structure with a 0.1mm optical transmittance protection layer, the Blu-ray Disc diminishes aberration caused by disc tilt.  This also allows for disc better readout and an increased recording density.  The Blu-ray Disc’s tracking pitch is reduced to 0.32um, almost half of that of a regular DVD, achieving up to 27 GB high-density recording on a single sided disc. 

Because the Blu-ray Disc utilizes global standard MPEG-2 Transport Stream compression technology highly compatible with digital broadcasting for video recording, a wide range of content can be recorded.  It is possible for the Blu-ray Disc to record digital high definition broadcasting while maintaining high quality and other data simultaneously with video data if they are received together.  In addition, the adoption of a unique ID written on a Blu-ray Disc realizes high quality copyright protection functions.

The Blu-ray Disc is a technology platform that can store sound and video while maintaining high quality and also access the stored content in an easy-to-use way.  This will be important in the coming broadband era as content distribution becomes increasingly diversified.  The nine companies involved in the announcement will  respectively develop products that take full advantage of Blu-ray Disc’s large capacity and high-speed data transfer rate.  They are also aiming to further enhance the appeal of the new format through developing a larger capacity, such as over 30GB on a single sided single layer disc and over 50GB on a single sided double layer disc.  Adoption of the Blu-ray Disc in a variety of applications including PC data storage and high definition video software is being considered.