Patent · US Expired

Fiber optic sensing system

US5986749A · kind A · utility

65Cited by
8References
33Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 19, 1997
Grant dateNov 16, 1999
Priority date
Expiry dateSep 19, 2017

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG08C23/06
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A fiber optic sensor includes a sensor element responsive to a property or condition of a material, such a resistivity, capacitance, inductance, frequency, etc., for providing an output voltage signal that is dependent upon the property or condition of the material. The sensor further includes an optical-to-electrical conversion element, such as a photo detector or a solar cell, that converts an optical signal (photo detector driving optical signal) carried by an optical fiber into an electrical signal. The electrical signal is applied to the sensor element, and in response, the sensor element provides the output electrical signal. The output electrical signal is applied to a measurement device, such as a piezoelectric element, having at least one dimension that varies with changes in the output electrical signal. An optical strain sensor, such as a Bragg grating or Fabry Perot interferometer, is mounted to the measurement device such that changes in the dimension of the measurement device causes changes in the strain of the optical strain sensor. These changes in strain are detected and related to the property or condition of the material. The fiber optic sensor is particularly us…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.