Semiconductor laser with a rewritable wavelength stabilizer
US6363097B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 18, 1998 |
| Grant date | Mar 26, 2002 |
| Priority date | — |
| Expiry date | Sep 18, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01S3/1055
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A semiconductor laser with a rewritable wavelength stabilizer which comprises a laser mirror made of a grating written into a photorefractive material, in which the oscillation wavelength of the laser diode is determined by the period of the grating. This allows the refractive index of the grating to be changed by illuminating the photorefractive material after cooling thereof to a temperature at which most of the doped impurities form DX centers. The grating can be erased by heating the photorefractive material to a temperature at which most DX centers are ionized, which erases the grating. Thereafter the photorefractive material is cooled again to a temperature at which most impurities become DX centers, and a new grating can be written in the photorefractive material. The wavelength of the semiconductor laser can be changed repeatedly by erasing and rewriting the grating therein. The laser diode is maintained and operated at a low temperature to maintain the grating semi-permanently therein while the temperature remains low.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.