The demand to "large-scale-izing of record media" has a strong thing. For example, a high definition high quality TV image is set to no less than 20GB by part for 2 hour. Furthermore, birth of the record media which are easy to use with large scale is desired now [ when it progresses to high definition-ization ].
□ Although "Blu-ray Disc" with the capacity of 27GB is commercialized as next-generation media of DVD, this sets to about 1/5 of DVD area (optical spot) as which blue laser is adopted and which laser light hits, and is pulling up record density 5 times.
Although it is necessary to make optical spot small in order to make a small record mark, since the focal length of a lens becomes short for the reason and the distance of a lens and a disk is shortened, it is becoming difficult physically.
□ Then, the way of thinking of recording a many layers record layer on each class in piles like pie cloth was produced.
□ The theoretical backing as research of a university is produced several years ago. In order to advance the "utilization", in Optoelectronic Industry and Technology Development Association, each university and a maker cooperate and research and development in basic technology is done. Ricoh took charge of and did research and development in the technology recorded and reproduced by "application of the conventional optical system" in the multilayered record layer, and advanced one step to "utilization."
□ Since basic technology was built now, I want to continue research and development after this aiming at utilization of 2010 age..."
For more information click at the 'Source' link (Japanese only)!