Optical pressure-sensing system using optical resonator cavity
US4933545A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 30, 1985 |
| Grant date | Jun 12, 1990 |
| Priority date | — |
| Expiry date | Dec 30, 2005 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S72/705
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An optical pressure-sensing system in which an optical beam splitter couples input light from a light source to an optically resonant pressure sensor and couples output light reflected from the sensor to a light detector. The light detector may divide the output light into bands having different wavelengths and then take the ratio of the light in one band to the light in the other band in order to provide an output that is insensitive to various spurious responses in the system. The optical beam splitter may be formed by two pairs of graded refractive index lenses. A partially reflective, partially transmissive mirror is sandwiched between the lenses of one pair, while a dichroic mirror is sandwiched between the second pair. The pairs of lenses are placed in abutting relationship to each other. The optical beam splitter may also be formed by a block of transparent material having a partially reflective, partially transmissive mirror on one edge. The optical pressure sensor is formed by a transparent substrate having a cylindrical recess and a resilient diaphragm positioned over the recess to form an optically resonant cavity. Differential pressure may be sensed by placing a second …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.