The TDK Professional Disc, which uses a blue-violet laser with a short wavelength for recording and playback, boasts a capacity of 23.3GB – approximately five times that of DVD media – as well as a rapid transfer rate of 72Mbps. Thanks to its random data access capability and other features available only from optical disc media, it can be expected to find growing acceptance in broadcasting applications.
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By use of a blue-violet laser with an extremely short 405nm wavelength, a large recording capacity of 23.3GB – about five times that of a DVD disc – is realized on a disc of the same size. In addition, high-sensitivity phase change materials and an optimized layer structure allows for a high-speed transfer rate of 72Mbps (144Mbps with two optical heads) with stabilized recording and playback.Source: TDK