TDK presented a prototype 10-layer, 320GB disc at the CEATEC Japan 2009 convention. The new optical disc holds six times the capacity of Blu-ray’s BD50 (50GB) media. Each layer accommodates 32GB compared to 25GB for a Blu-ray disc layer. However, it appears data on the new TDK disc can be written and read using existing Blu-ray hardware.

Technology websites report that, rather than using a sharper laser than the current BD’s blue wavelength of 405 nm, the 10-layer disc features a better top surface capable of transmitting 99% of the light through it. Despite the larger number of layers, TDK reports that the error rate remaining at the "threshold of commercial viability" using standard lasers for reading and writing.

The disc improves on Sharp’s 100GB prototype and on TDK’s own 200GB disc shown in 2006, but holds less data than a 400GB prototype disc that was presented by Pioneer last year. The Pioneer disc packed 16 recording layers onto a conventional 1.1-millimeter thick, 12-centimeter disc.

Reacting to this announcement, Andy Parsons, Chair of the Blu-ray Disc Association promotion committee in the US, does not foresee the new higher capacity technology replacing the current BD50 format. “"I think there will be applications for larger capacity recordable discs, but it would be difficult for [discs larger than 50GB] to achieve compatibility with the installed base of players," he said. "This is because player manufacturers design players to meet published specifications that define maximum media capacity, which in the case of Blu-ray Disc, is 50GB on two-layer media," he said.

For now, these larger discs are being positioned for use as BD-R/RE for storage of data rather than film playback.

Story filed 10.10.09