Sagnac type optical fiber interferometer system
US4848910A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 1, 1988 |
| Grant date | Jul 18, 1989 |
| Priority date | — |
| Expiry date | Jun 1, 2008 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R15/246
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The optical fiber interferometer system is used either in a gyroscope or else for measuring electrical current by the Faraday effect. It includes an optical board (100) which is connected to the two ends of a monomode optical fiber (200) constituting an interferometer ring, said optical board including a photodetector (103) which is colinear with the light source which is coupled by both its front and its rear faces. The two counter-propagating beams travelling round the interferometer ring have their relative phase difference modulated by phase modulation and their light power modulated by amplitude modulation. An electronics board (300) generates these modulations and, from the photodetector signal (103), it extracts a component at the lower beat frequency between said two modulation frequencies, thereby making it possible to measure the relative phase difference between the two beams.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.