一种高精度光学位移传感器的设计分析

Design of a High-precision Displacement Sensor

利用晶体双折射和由散射偏振引起的光学干涉技术 ,设计出一种高精度光学位移传感器 该传感器采用同轴光学系统 ,测量精度约为 4 μm ,测量范围不小于 2 8mm ,且测量时不需要使用相干光源 ,故结构紧凑。

Based on birefringent interference high precision displacement sensor is designed. A laser beam emitting from a build-in LD in the sensor points to the detected surface, and the dispersed light goes through the optical lenses and a birefringent crystal. The ordinary ray and extraordinary ray from the crystal interfere at a detector. As the distance from the sensor to a target changes, the interference fringes shift. By detecting movement of the fringes, the displacement can be calculated. Precision of the sensor can achieve micron.