Sony has done some great research in holographic field through which storing 500GB data (using 20 layers) on a 12cm disc will be possible by about 2010. Using "Micro-Reflector method" -- a multilayer recording technology using holographic recording -- Sony wrote and read data on a medium equivalent to a seven-layer disc. The company reported experimental results where data were recorded at a speed of 1050rpm, and the equivalent data transmission speed was 3Mbps.

The in-house scientists have loads of work to do as the firm wants to speed up data transmission speed, improve memory density per layer and increase the number of recording layers.

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