According to the New Scientist, the "multilayer dual optical disk" has one layer of data in the standard CD or DVD format, a second layer able to play Blu-Ray and the other HD-DVD.
It will mean that consumers can pick which one they want without having to invest shedloads in hardware that might not survive second generation DVD war. It also means that the studios do not have to pick one technology over another and can provide the content in both.
The patent application was filed by Wayne Smith, Alan Bell and Lewis Ostrover. It works by storing the information at different depths depending on the technology. Blu-ray discs store information only 0.1 millimetre from the surface while HD-DVD discs store it at 0.6 millimetres.
The boffins say that by using reflective films lasers can read the top layer and "see through" to the lower one if necessary. Additional information also could be stored on the other side of the disc.
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