Early experiments on optical disc storage

Optical technology was early proposed to attain information density higher than 10 Gb/in(2) with fast data transfer for storage of video, audio, or co mputer data either using holography or bit-by-bit memory architectures. We present in the paper how the concepts and technological issues have progres sed at THOMSON-CSF and in other laboratories for the demonstration of an op tical pickup enabling the readout of a 30-min TV program recorded as microt ips on a spinning disc, The main technical breakthroughs are presented unti l first commercial success was achieved with the compact optical audio disc (CD) and evolution toward the optical CD-ROM and the DVD. Future research directions for achieving extremely high capacity in a compact system are al so discussed.