Solid medium optical ring laser rotation sensor
US5408492A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 21, 1993 |
| Grant date | Apr 18, 1995 |
| Priority date | — |
| Expiry date | May 21, 2013 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01C19/66
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An optical rotation sensor comprises a light amplification stimulated emission ring laser formed in a solid medium is provided with phase modulator devices which produce push-pull phase modulation of counterpropagating optical waves in the ring thereby enhancing bidirectional lasing in single longitudinal modes in each direction. A frequency selective output coupler couples a predetermined portion of the optical energy at the lasing frequency from the ring to an output waveguide. A substantially U-shaped output waveguide having legs extending away from the ring in opposite directions and toward a common position. Clockwise and counterclockwise light waves are coupled from the ring to the two separate legs of the output waveguide and are directed to the common position to create an interfering light pattern on photodetector apparatus. The interfering light pattern is indicative of the rate of rotation, as defined by the Sagnac effect. Signal processing circuitry connected to the detector derives navigation and flight control information from the detector. In one embodiment, the ring laser and input and output couplers are implemented in a rare earth-doped lithium niobate substrate. …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.