Intermodulation product stabilized laser
US5029174A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 5, 1989 |
| Grant date | Jul 2, 1991 |
| Priority date | — |
| Expiry date | Dec 5, 2009 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01S3/139
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A method and system for stabilizing the output frequencies of a multimode laser of the type which operates in at least three optical cavity modes includes detecting the intermodulation product frequency, using a suitable photodetector. The optical cavity modes may be either purely longitudinal for a single transverse mode, or may include radiation from multiple transverse cavity excitations, also with possible longitudinal plurality. The detector output is monitored for the intermodulation product beat signal which is contained in the detector current at the differences of the primary difference frequencies of the optical modes. A signal derived from the frequency of the intermodulation product term is compared with a reference signal, and the resulting error signal is driven to zero by varying the optical length of the laser oscillator cavity in response to the error signal, thereby causing the operating modes of the laser to be stabilized. Possible means of adjusting optical cavity length include, but are not limited to, thermal expansion or contraction of the resonator support structure which is used to establish the relative spacing of the laser's end mirrors, by piezoelectric …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.