HD DVD’s dual-layer 30GB and Blu-ray’s dual-layer 50GB media is enough space to store crystal-clear 1080p video and uncompressed audio for today's movies, but media manufacturers are continuously looking for ways to increase capacity. Toshiba Corporation quietly announced on the first day of CES that the company has developed a triple-layer HD DVD-ROM (read only) disc with a capacity of 51 gigabytes.
HD DVD discs hold 15GB per layer, so in order to reach a dual-layer Blu-ray Disc-besting capacity, an extra 2GB per layer was squeezed in to reach 51GB. Toshiba states that continued improvement in disc mastering technology has achieved further minimization in the recording pit, allowing for the boost in capacity to 17GB in single layer and a full 51GB on a single-sided triple-layer disc.
The new disc shares the same disc structure as standard DVD and previously announced HD DVD formats: two 0.6-mm thick discs bonded back-to-back. According to Toshiba, the added cost to produce discs with the third layer is minimal, thanks to the use of the same physical disc structure as DVD. Toshiba aims to secure approval of the new disc by the DVD Forum within this year.
While Toshiba has publicly announced its achievement, Ritek is disclosing behind closed doors at CES its own achievements in multi-layer HD optical media. Ritek claims to not only have been able to produce a three-layer and four-layer HD optical discs, but to have successfully designed HD media with a full 10 layers. The company says that its multi-layer process can be applied to both HD DVD and Blu-ray formats.
At base specifications, 10 layers on an HD DVD would yield 150GB, assuming 15GB per layer. For Blu-ray, the total over 10 layers jumps to 250GB, assuming the base 25GB per layer.
While those numbers do sound impressive, Ritek officials point out that the real barrier to this advancement is the lack of reader and writer laser diode technology to support the additional eight layers above the current standard.