Optical information recording and reproducing apparatus having volume holographic memory
US6900914B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 29, 2000 |
| Grant date | May 31, 2005 |
| Priority date | — |
| Expiry date | Mar 29, 2020 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2007/0009
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A description is provided of an optical information recording and reproducing apparatus having a volume holographic memory. The apparatus is capable of recording an interference pattern in the volume holographic memory in high density and can be made small-sized. The apparatus includes a comprises support portion for detachably supporting the volume holographic memory, which is made of a photorefractive crystalline material; a reference beam supplying portion for making a coherent reference beam of a first wavelength incident on the volume holographic memory; a signal beam generating portion for making a coherent signal beam of the first wavelength, which is modulated in accordance with image data, incident on the volume holographic memory, intersecting therein the signal beam with the reference beam, and generating a three-dimensional light interference pattern of the signal beam and the reference beam; and detecting a portion for detecting diffracted light from a refractive index grid of the light interference pattern in the volume holographic memory, due to irradiation of the reference beam. The signal beam and the reference beam are arranged in a plane having a normal line perp…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.