A holographic process is provided for recording-reading by means of index strata in the volume of a photoexcitable storage medium. This process consists in causing two beams to interfere in this medium during two successive writing steps by using writing radiations of different wavelengths. The reading...http://www.google.com.au/patents/US4592618?utm_source=gb-gplus-sharePatent US4592618 - Holographic recording and related reading process
