Coherence multiplexing of in-line displacement and temperature sensors

Abstract

A novel in-line multiplexing scheme for optical displacement and temperature sensors based on low-coherence interferometry is presented. It allows the measurement of deformations with a resolution of 10 μm and temperatures with a resolution of 1°C m. The multiplexing of two displacement sensors and one temperature sensor along the same fiber line is demonstrated experimentally, and a theoretical calculation for a system with 10 sensors is presented. This type of sensor would be especially useful for the long-time monitoring of large structures.