REFLEX FIBER OPTIC SENSOR FOR MICRO-ANGULAR DISPLACEMENT MEASUREMENT

摘要

A reflex fiber optic sensor for two-dimensional angular displacement measurement is proposed. It uses four linear light receiving fiber arrays arranged as a crisscross spoke and a charge-coupled device (CCD) as the detector for the reflex modulated light information. Light intensity received by each receiving fiber will change due to the measured angular displacement and be recorded by the CCD. Based on the Gauss distribution theory, reflected light spot center can be determined by fitting a Gauss curve according to each received light intensity and the position of each receiving fibers. With this method, measurement errors caused by surface reflection index variation, light power fluctuation, and ambient light disturbance will be effectively avoided. Sensor structure and measurement principle is described.