ERASABLE/REWRITABLE OPTICAL DATA STORAGE WITH PHOTOREFRACTIVE POLYMERS

摘要

A method of erasable/rewritable optical data storage is provided in which a laser beam from a laser (10) operated in either a pulsed or continuous wave mode is focussed by an optical system (11-18) onto a photorefractive polymeric material (32) to cause two photon excitation of the material to record data which may subsequently be erased by illuminating the material with radiation having a wavelength in the ultraviolet or visible spectrum to erase the recorded data. New photorefractive polymeric materials having a relatively narrow absorption band for use in the method are also disclosed.