Fiber—optic displacement sensor

Abstract

This paper describes a microbend displacement sensor with high sensitivity and wide dynamic range designed on the bases of multimode sensor—oriented fiber. A number of high sensitive sensors has been design on the basis of microbending induced mode coupling of core to clad modes.'2 Usually these sensors need very accurate alignment of input end face with light source for selective mode excitation. We propose a modified sensor configuration based on miorobending induced mode coupling. With a modified sensor configuration the alignment requirements are reduced and the possible sensitivity to some extent is higher than with conventional configuration sensor.