Pioneer 16-layer BD
New disc uses 16 layers glued together - and is back-compatible with existing players

Pioneer has developed the world's first 400GB read-only optical disc, opening the way to future releases able to store much more content than current disc formats.

Using no fewer than 16 layers glued together, and each holding 25GB, the disc is able to store about eight times more data than existing dual-layer Blu-ray Disc media, and is said to be fully backwards-compatible with existing players.

The disc, details of which will be announced at the forthcoming International Symposium on Optical Memory and Optical Data Storage 2008 to be held in Hawaii from July 13, is currently a read-only type - just like commercially-pressed Blu-ray Disc titles. However, Pioneer says the technology is also applicable to multilayer recordable discs.

The company has used experience gained in DVD manufacture to solve the problem of getting a clear signal from each recording layer and transmission loss, by altering the disc structure to avoid inter-layer crosstalk.

More after the break

It has also developed a reading system able to handle weak signals, but maintains that the optical specifications of the reading lens are the same as those used for existing Blu-ray Disc media, so compatibility can be maintained between current and future discs.