Method for reading out rotation rate with a passive optical resonator
US4825261A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 28, 1987 |
| Grant date | Apr 25, 1989 |
| Priority date | — |
| Expiry date | Jul 28, 2007 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01C19/727
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A rotation rate readout method employing a passive optical resonator. The ring resonator is operated at approximate resonance in reflection and rotation rate-dependent phase shifts are detected, in particular as first harmonics, in the resonator. Two partial light beams are first frequency shifted by equal and opposite amounts, such frequency shift being modulated. Light components coupled out of the resonator pass through a mode filter in the opposite direction and are detected as an interference signal by an opto-electronic converter. The latter signal is demodulated with respect to the modulation frequency or its harmonics and the rotation rate signal obtained therefrom. Self-compensation of the optical and electronic readout systems may be attained by periodic brief and strong damping of the ring resonator. In contrast with known methods wherein two channels are separately processed and two mode filters required, the interference signal is processed in accordance with the invention requiring only a single mode filter.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.