Patent · US Expired

Optical acoustic sensor

US4375680A · kind A · utility

53Cited by
9References
31Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 16, 1981
Grant dateMar 1, 1983
Priority date
Expiry dateJan 16, 2001

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01H9/004
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A light source is operated near its threshhold and its output is split and sent in opposite direction about a fiber optic coil which is exposed to acoustic energy. The recombined light out of the coil is modulated at acoustic frequency. The modulated light can be fed back to the light source which responds to the modulation with large amplitude variations which are sent to a detector for conversion into an electrical signal representative of the acoustic energy. Alternatively, the light beam may be directed from the fiber coil to the detector directly. The sensors can include components for rejecting noise at frequencies not of interest and a plurality of similar sensors can be formed in an array to obtain directional information or increased sensitivity.

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