Influence of fiber geometry on the performance of two-fiber displacement sensor

The performance of two-fiber, intensity modulated Fiber Optic Displacement Sensor (FODS) is governed by the geometrical parameters like the offset between the transmitting and receiving fiber tips ( h), lateral separation between the transmitting and receiving fibers ( s), the angle between transmitting and receiving fibers and the angle of the reflector ( θ r). While manufacturing FODS there is likelihood of deviation of these parameters from ideal designed value. This may influence the performance of FODS. This paper is an attempt to find the influence on the performance of FODS. Present paper describes the simulation of FODS based on mathematical model. The dependence of performance metrics such as blind region, linear range, sensitivity and the peak position on the geometrical parameter is reported. From parallel fiber to inclined fiber the sensitivity increases and at 30° it becomes 16% of the parallel fiber. With angle of reflector θ r sensitivity increases and becomes 1.63% of the value with zero angle of reflector. With separation between the fibers the sensitivity reduces to 27% at 1 mm distance between the fibers as with no distance between the fibers, however with change in offset the sensitivity remains constant.