Pioneer, 400GB Optical Discs

Pioneer has produced a 16-layer read only optical disc which it claims can store 400GB of data.

25GB per-layer capacity is, the same as that of a Blu-ray Disc, the multilayer technology will also be applicable to multilayer recordable discs.

Pioneer’s Multi layered discs have been hard to develop because 'crosstalk' from adjacent layers and transmission loss mean that producing a stable signal from the disc is nearly impossible.

The company achieved stability in the playback of recorded signals by employing a wide range spherical aberration compensator and light-receiving element that can read out weak signals at a high signal-to-noise ratio in the optical pick-up mechanism.

The large capacity of these discs means that the new technology will be best suited for applications such large volume data archiving, not consumer use.

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