Technique for locking a laser diode to a passive cavity
US5555253A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 7, 1995 |
| Grant date | Sep 10, 1996 |
| Priority date | — |
| Expiry date | Jun 7, 2015 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01S5/142
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A laser is disclosed whose resonant cavity includes a back facet of a semiconductor gain element as one mirror and a passive resonator as part of a second mirror. Appropriate optics are provided for a round-trip path within the resonant cavity that avoids double-passing the passive resonator so that intracavity losses are reduced and more power is fed back to the gain element, which is the active medium of the laser. By ensuring a high percentage feedback of the radiation to the semiconductor gain element, amplitude stable operation can be achieved while locking the frequency of the gain element to the passive resonator. By providing both frequency and amplitude stable operation, fluctuation of the circulating power in the passive resonator is minimized and, therefore, can be usefully employed for many applications. For example, non-linear crystals of well-known types can be placed within the passive resonator in order to achieve highly efficient second harmonic generation in a power regime and with frequency and amplitude stability that was heretofore unobtainable.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.