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Electronista: Sharp on Friday revealed a blue-violet laser that it says could lead to triple-layer or even quad-layer Blu-ray discs.

The light is as strong as 500mW and achieves the feat by putting an aluminum oxynitride layer between the laser’s crystal and the usual dielectric film meant to protect the laser, eking out more output than would normally be possible with just the dielectric element alone.

It would not only allow a drive to read twice as deep as current dual-layer Blu-ray drives but would let it write at 8X speed on all four layers. Using current technology, which fits 25GB for each layer of a disc, the advancement would allow 75GB or 100GB recordable discs and would be useful not just for data backup but also for producing and editing movies, where the size of 1080p movies often limits long-format movies or those with special features.

Sharp hasn’t said how soon it would expect the technology to reach shipping products

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Macsimum News:  TDK says it’s achieved a capacity of 200GB that will double the capacity of their current 100GB Blu-ray prototype. One 200GB disc could store approximately 18 hours of high definition video.

The initial Blu-ray Disc standard allows for 25GB single layer Blu-ray Discs and 50GB dual layer Blu-ray Discs. However, a recent signal processing innovation stretches the physical limits of optical media, realizing 33.3GB capacity for each of the disc’s six layers. As with the 100GB disc, and other Blu-ray Disc media, TDK’s 200GB blue laser disc is single-sided.

The company’s 100GB prototype disc uses four 25GB layers to reach 100GB capacity. For the 200GB technology development, TDK has stretched the physical margins of the Blu-ray Disc format, enabling a disc to store up to 33.3GB per layer while staying within the tolerances of the BD playback specifications, according to Bruce Youmans, vice president of product research & development.

A single-layer Blu-ray Disc can hold 25GB, which can be used to record over two hours of HDTV or more than 13 hours of standard-definition TV. There are also dual-layer versions of the discs that can hold 50GB.

TDK has already begun shipment of its single-layer 25GB recordable and rewritable media in the first quarter of 2006.  50GB discs, which are dual layer, have now just begun shipping, retaililng at €35 for a write-once, and €45 for a re-writeable disc.

More at CD Freaks.com

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