Micro-Displacement Sensor Combined With a Fiber Ring Interrogated by an Optical Time-Domain Reflectometer

A micro-displacement sensing head based on two aligned cleaved fibers inserted into an optical fiber ring and interrogated by an optical time-domain reflectometry is presented. The sensor configuration is characterized for measuring both longitudinal and axial micro-displacements, showing a sensitivity of 0.07 and 2.67 dB/μm for longitudinal and axial micro-displacements, respectively. A multiplexing system using two of these configurations is also studied.