Method and apparatus for eliminating Kerr effects in a ring gyro
US5098188A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Feb 14, 1990 |
| Grant date | Mar 24, 1992 |
| Priority date | — |
| Expiry date | Feb 14, 2010 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01C19/727
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
To overcome Kerr effect induced gyro bias in a ring resonator optical gyro, the intensities of the beams travelling in opposite directions around the ring have to be very accurately matched. To achieve this a ring resonator gyro includes a first optical coupler (6), the coupling ratio of which is variable and which divides light from a laser (1) into a first and a second component of generally equal intensity, a second optical coupler (8) which transmits a predetermined proportion of the first component to one input of the ring resonator (15) for transmission around the ring resonator (15) in one sense, and a third optical coupler (9), the coupling ratio of which is variable to couple a variable proportion of the second component to the other input of the ring resonator (15) for transmission around the ring resonator (15) in the opposite sense. The gyro also includes a detector (16) for sensing the intensity of light scattered from the optical ring resonator (15), a square wave generator (40) for periodically varying the coupling ratio of the first coupler (6), sample and hold circuits (45-48) responsive to the output of the detector (16) as the coupling ratio of the first coupler …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.