Fiber-optic sensor with two different wavelengths of light traveling together through the sensor head
US4703175A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 19, 1985 |
| Grant date | Oct 27, 1987 |
| Priority date | — |
| Expiry date | Aug 19, 2005 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01K11/14
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A fiber-optic system for measuring a desired environmental parameter, such as temperature, is disclosed. The system includes a fiber-optic sensing head that alters light of a prescribed frequency as a function of the environmental parameter to be measured. Light not of the prescribed frequency is not so altered. In a preferred embodiment of the fiber-optic sensing head, a semiconductor material is positioned between two substantially parallel optical fibers at a distal end of the fibers. One fiber serves as in input channel and the other fiber serves as an output channel. Both fibers approach the semiconductor material from the same direction. Light channeled to the semiconductor material is reflected at the distal end of the input fiber so as to pass through the semiconductor material, and then is reflected again at the distal end of the output fiber so as to pass back out the output fiber. The semiconductor material absorbs the light of the prescribed frequency as a function of temperature. By monitoring the intensity of the light of the first frequency at the output channel, a measurement of the temperature to which the fiber-optic sensing head is subjected can be determined. To…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.