Fibre optic sensors.

摘要

A fibre optic sensor in which the sensed parameter acts upon particles present in a plastics coating surrounding an optical fibre in such a way that the action modifies an optical propagation characteristic of the fibre. Thus the change in optical path length of the fibre included by the surrounding ferrite particle loaded plastics layer in the presence of a magnetic field provides the fibre with sensitivity to magnetic fields which can be detected by optical interferometry.