Laser fiber optic gyroscope having phase modulation
US5459575A · kind A · utility
28Cited by
5References
8Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Feb 25, 1994 |
| Grant date | Oct 17, 1995 |
| Priority date | — |
| Expiry date | Feb 25, 2014 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01C19/72
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
In a laser gyroscope, a non-reciprocal phase modulation is introduced between the clockwise (CW) and counterclockwise (CCW) beams at a modulation frequency (f). The CW and CCW beams are combined on a detector and the intensity of the output is observed at the fundamental frequency (f) and the higher harmonics (e.g. 2f, 4f). At each frequency, the detected signal is demodulated by mixing it with a reference signal at the same frequency and stepping the phase of the signal through successive increments of 90.degree., thereby to determine the in-phase and quadrature components for each frequency monitored.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.