Optical fiber sensing systems
First Claim
1. An optical fibre sensing system for measuring the location and/or magnitude of an external parameter acting at a single point along an optical fibre loop sensor, in which the system comprises light source means for producing light for propagation in opposite directions around said loop sensor, directional coupler means for coupling said light source means and detector means to said loop sensor and to other optical fibre interfering paths of the system, in which the detector means are arranged for measuring a phase change (x) between interfering light signals propagating around the sensor loop in opposite directions and for simultaneously measuring a phase change (y) experienced by the light propagating around the loop sensor in one direction, whereby, by computation or otherwise, the rate of change of the phase change (x) can be derived and by the use of the algorithm herein defined the location and/or magnitude of the applied parameter can be determined.
2 Assignments
0 Petitions
Accused Products
Abstract
An optical fiber sensing system for measuring the location and/or magnitude of an external parameter acting at a single point along an optical fiber loop sensor. The system comprises light source means for producing light for propagation in opposite directions around the loop sensor and directional coupler means for coupling the light source means and detector means to the loop sensor and to other optical fiber interfering paths of the system. The detector means are arranged for measuring a phase change (x) between interfering light signals propagating around the sensor loop in opposite directions and for simultaneously measuring a phase change (y) experienced by the light propagating around the loop sensor in one direction. By computation or otherwise, the rate of change of the phase change (x) can be derived and by the use of an algorithm the location and/or magnitude of the applied parameter can be determined.
53 Citations
5 Claims
- 1. An optical fibre sensing system for measuring the location and/or magnitude of an external parameter acting at a single point along an optical fibre loop sensor, in which the system comprises light source means for producing light for propagation in opposite directions around said loop sensor, directional coupler means for coupling said light source means and detector means to said loop sensor and to other optical fibre interfering paths of the system, in which the detector means are arranged for measuring a phase change (x) between interfering light signals propagating around the sensor loop in opposite directions and for simultaneously measuring a phase change (y) experienced by the light propagating around the loop sensor in one direction, whereby, by computation or otherwise, the rate of change of the phase change (x) can be derived and by the use of the algorithm herein defined the location and/or magnitude of the applied parameter can be determined.
Specification