Photorefractive systems and methods
US5684611A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 6, 1995 |
| Grant date | Nov 4, 1997 |
| Priority date | — |
| Expiry date | Jun 6, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03H2001/266
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A new type of holographic recording in photorefractive crystals is disclosed, termed orthogonal data storage, in which counterpropagating, reflection mode holograms are wavelength multiplexed to form gratings lying along a common axis. It is shown that this configuration provides substantial improvements in data storage capacity in comparison to prior art systems and that higher coupling coefficients are achieved. In consequence, not only storage of data but a wide range of other devices including wavelength selective filters, lenses and optical correlation systems are disclosed. Further, methods of writing and processing metastable images are disclosed which substantially improve the strength of the gratings that are permanently developed in the medium. These methods include advantageous use of electrical potentials and photovoltaic properties, together with different interrelationships during processing.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.