Multiple focus backward Raman laser apparatus
US5090016A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 15, 1991 |
| Grant date | Feb 18, 1992 |
| Priority date | — |
| Expiry date | Feb 15, 2011 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01S3/305
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A Raman laser apparatus for producing a high energy output beam with low divergence. An optical pump beam (14) propagates through first and second focuses (34,36) inside a cell containing a gaseous Raman medium (20) at a pressure selected to promote stimulated Raman scattering (SRS) and suppress stimulated Brillouin scattering (SBS). The pump beam (14) generates a backward SRS wave at the second focus (36), which propagates back through the first focus (34) and acts as a seed for backward SRS therein. The backward SRS wave is amplified at the first focus (34), and extracted therefrom as an output beam (38) by output means (40). Any forward SRS wave which is generated at either the first focus (34) or the second focus (36) may be reflected back through the second focus (36) and then through the first focus (34) to further increase the backward SRS seed beam at the first focus. The output beam (38) is retro-reflected, and has beam divergence comparable to the pump beam divergence. The two focal points (34 and 36) may be in the same or separate Raman cells (16, or 16' and 18). In addition, more than two focal points may be used and these may be in the same or separate Raman cells.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.