Electro-optic holographic storage device having unlimited record-erase capability
US4063795A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 18, 1976 |
| Grant date | Dec 20, 1977 |
| Priority date | — |
| Expiry date | May 18, 1996 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02F1/0541
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
The present invention relates to a holographic optical storage device utilizing a material in which the transfer of photo-induced charges is orientated along the cristallographic axis C of the material. On the faces of the material perpendicular to said axis, two transparent electrodes connected together are arranged so that the field developed between said two faces is zero whatever the uniform illumination superimposed upon the modulation. The selective erasing of a first induced spatial variation in refractive index is achieved by recording a second spatial variation which is the complement of the first, the number of successive record-erase cycles being unlimited.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.