Self-pumped phase conjugate mirror and method using AC-field enhanced photorefractive effect
US4773739A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 5, 1986 |
| Grant date | Sep 27, 1988 |
| Priority date | — |
| Expiry date | Mar 5, 2006 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02F1/3538
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A self-pumped phase conjugate mirror and method is disclosed in which an optical beam is applied to a crystal formed from a photorefractive material, the beam is deflected back into the crystal as a return beam to cross-couple with the input probe beam, and an alternating electric field is applied across the crystal to establish a photorefractive index grating shift of about 90.degree. and bring the crystal gain up to a level at which phase conjugation takes place. By a suitable selection of field strength and frequency, and an angle between the probe and return beams within the crystal of less than about 5.degree. (3.degree. for GaAs), semiconductor materials with electro-optic coefficients of less than about 10 picometers/volt can be used as the conjugating medium. Such materials have previously not worked in a self-pumped conjugator, but are much more readily available, more responsive, and have improved bandwidths compared to substantially higher electro-optic coefficient refractive materials that have been used in prior inherently self-pumped conjugators.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.