Sensor system
US6137573A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 16, 1998 |
| Grant date | Oct 24, 2000 |
| Priority date | — |
| Expiry date | Sep 16, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01L1/242
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A sensor system (10) incorporating an interferometer operates as an optical strain gauge. The system (10) is arranged to generate interferograms characterised by an optical path difference between light traversing a sensor arm (12) of the interferometer and light traversing a reference arm (58). Each arm incorporates a highly birefringent optical fibre (38, 58) capable of supporting light propagation at two velocities in two different polarisation modes. A first interferogram is generated between light coupled into the fast eigenmodes of each fibre and a second is generated between light coupled into the slow eigenmodes. Mean optical group delay (.tau..sub.MGD) and differential optical group delay (.tau..sub.DGD) of these interferograms are affected differently by temperature and strain and thus provide a means of discriminating between these attributes of the sensor environment. Thus simultaneous measurement of strain and temperature is achieved.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.