OPTICAL-FIBER VIBRATION SENSOR USING STEP INTERFEROMETRY

摘要

An all-fiber vibration sensor based on step interferometry is described. The sensor consists of a modified Michelson interferometer in which the ends of the reference and signal arms are assembled and fixed together to produce regular distributed interference fringes. Five photodetectors with relative phase shifts of pi/2 placed on the fringes acquire five intensity patterns simultaneously. One reconstructs the vibration amplitude by using the well-known five-step algorithm. A vibration sensor with these characteristics was constructed, and its performance was investigated. (C) 1996 Optical Society of America [References: 11]