基于法拉第旋光效应的激光外差干涉测量系统的优化设计

Optimal Design of Laser Heterodyne Interferometric Measurement System Based on the Faraday Effect

描述了基于法拉第旋光效应的激光外差干涉测量方法及其系统,通过分析测量平面镜顺时针和逆时针转动时光路结构的几何关系确定了该系统实施纳米位移测量应满足的条件,重点讨论了角锥棱镜固定时测量平面镜、波片和角锥棱镜三者之间的位置关系,实现了基于法拉第旋光效应的激光外差干涉测量系统的优化设计,得出了位移测量范围为-10～10mm时允许被测对象转动范围最大的系统参数,为该系统的研制奠定了技术基础。

The laser heterodyne interferometric measurement system based on the Faraday Effect is described. By analyzing the geometric relationship of the optical configuration of the system when the meas- urement mirror is rotated in clockwise and counterclockwise, the conditions to ensure the system to realize nanometer displacement measurement are determined. The position relationships of the measurement mir- ror, the wave plate and the retroreflector are discussed in detail when the retroreflector is fixed. And then the optimization design for the system is implemented. The optimal parameters of the system with the displacement range of -10 -10 mm is obtained while the measured object has a capable of maximal rotary angle. This provides a technical support for the development of the system.