Optical fibre temp. or vibration sensor - has monomode optical fibres which are insensitive to detected variable for transporting beam to and from multimode fibre loop acting as transducer

摘要

The sensor comprises a section of multimode optical fibre (1) with one end (2) connected to a source of light (6) and the other end (3) connected to an analyser (8). Light is carried to the multimode fibre through monomode waveguides (7,9). The monomode sections (7,9) are unaffected by the parameters measured by the multimode section (1). The monomode receiver section (9) is displaced laterally in order to receive part of the transmitted light beam from the multimode sensing section (1). USE/ADVANTAGE - Eg for microphone. Detects vibration or temperature unaffected by environmental conditions of monomode fibres.