Patent · US Expired

Optical information recording and reproducing apparatus using a holographic memory

US6414762B1 · kind B1 · utility

3Cited by
6References
5Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 23, 2000
Grant dateJul 2, 2002
Priority date
Expiry dateMar 23, 2020

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03H2001/0268
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

An optical information recording and reproducing apparatus, which detachably supports a holographic memory formed of a photorefractive crystal, includes a portion for supplying a coherent reference light beam at a first wavelength into the holographic memory; a portion for supplying a coherent signal light beam at the first wavelength, modulated in accordance with image data, into the memory to produce an optical interference pattern with the reference light within the memory; a portion for supplying a gate light beam at a second wavelength into the memory for activating or deactivating an index grating in accordance with the presence or absence of the optical interference pattern to enhance a photo-sensitivity of the memory; a detector for detecting diffraction light from the index grating of the memory by the irradiation of the reference light beam; and a portion for changing and regulating a light intensity of the gate light beam.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.