High speed photorefractive image comparator
US4921353A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 5, 1988 |
| Grant date | May 1, 1990 |
| Priority date | — |
| Expiry date | Jul 5, 2008 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06E3/001
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A phase conjugate interferometer for combining first and second two dimensional images includes a source of coherent light and a first beam splitter for dividing the coherent light into a transmitted beam and a reflected pump beam. A second beam splitter divides the transmitted beam into a reflected first probe beam which traverses a first image transparency and a transmitted second probe beam which traverses a second image transparency. A nonlinear optical medium receives the reflected pump beam, the first probe beam, and the second probe beam, with the medium, the pump beam, and the probe beams being oriented such that self-pumping of the reflected pump beam produces counterpropagating pump beams, four-wave mixing between the counterpropagating pump beams and the first probe beam produces a phase-conjugated first output beam which traverses the first image transparency, and four-wave mixing between the pump beam and the second probe beam produces a phase-conjugated second output beam which traverses the second image transparency. The second beam splitter, the first output beam, and the second output beam are oriented such that a portion of the first output beam is transmitted by …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.