Optical measurement system with light-driven vibrating sensor element
US4521684A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 22, 1982 |
| Grant date | Jun 4, 1985 |
| Priority date | — |
| Expiry date | Feb 22, 2002 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01L1/08
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An instrumentation system for use in measuring and processing industrial process variables, such as flow, pressure, or temperature, includes a resonant element sensor whose resonant frequency varies in accordance with changes in the desired process variable communicating through an optical fiber link to a distant control room. The sensor is activated into resonant physical motion by light energy from a source in the control room, while the motion of the wire is sensed optically and retransmitted to the control room to produce an output signal whose frequency is equal to that of the resonating element. A feedback network maintains the sensor in resonance by synchronizing the delivery of light energy to the motion of the resonant element. The powering and sensing aspect may be performed by individual fiber optic cables or alternatively this function may be combined by utilizing a single fiber optic strand.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.