Erasable optical disc memory system - has photo-refractive memory layer sandwiched between transparent layers and with information storage provided by creation of holographic patterns

摘要

The digital memory system uses information storage in a photo-refractive material (2) in which the information bits are retained as holographic patterns. The memory system is reversible and the information can be read using compact disc technology. The information may also be erased from the disc. The photo-refractive layer is located between two plain parallel substrates (1) that are transparent and are 10 to 2000 microns thick. Glass or transparent plastic may be used for the substrates. A reflective layer (3) can be located behind the refractive layer. The photo-refractive layer is of a liquid crystal poly-matrix in which the holographic forms are produced using a laser. USE/ADVANTAGE - Allows stored information to be erased. Stored information can, with suitable arrangement of the storing medium, be read by any existing CD player.