Strain and fabry-perot etalon measurement system and method
US5589641A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 5, 1995 |
| Grant date | Dec 31, 1996 |
| Priority date | — |
| Expiry date | Jun 5, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01B11/161
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A system and method for absolute, high resolution and accurate strain measurement includes a low-coherence light source (12) transmitting light through a strain sensor (18) and into an interferometer (26). The interferometer (26) has a high-coherence light source (48) that parallels the light from the low-coherence light source (12). The output of the interferometer is detected by a photodetector (46). The photodetector (46) is connected to a phase measuring circuit (30), that is in communication with a controller (28). The controller (28) is also connected to a motor (44) that adjusts the optical path lengths in the interferometer (38). The phase change in the high-coherence source from the fringe pattern (68) of the strain sensor (18) before and after a strain is applied to the device under test is used to determine the strain.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.