Fibre optic measuring device, rate gyro, stabilization system and magnetic field or current sensor
US5270791A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 13, 1991 |
| Grant date | Dec 14, 1993 |
| Priority date | — |
| Expiry date | May 13, 2011 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01C19/72
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The invention relates to a fiber optic measuring device in which the variation in a measured parameter engenders a phase difference between two waves. It comprises a SAGNAC ring interferometer (2) in which two counter-propagating waves propagate; a polarization splitter (6) spatially splits the two polarizations which will propagate in the interferometer (2), interferometer (2) comprises a polarization conserving birefringent fiber (7) having two ends having neutral birefringence axes, each of the ends of the polarization conserving fiber (7) being connected to one of the gates (6b) and (6c) of the polarization splitter (6). It comprises a birefringent component, placed ahead of the polarization splitter (6) and introducing a path difference greater than the coherence length of the source (1) between the two polarized waves.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.