提出了一种表面粗糙度测量的新方法.该方法采用了微分偏振干涉的原理,利用由法拉第磁光调制器所组成的调制系统对偏振干涉光路的位相进行调制,利用锁相干涉原理对位相进行探测.该方法可实现无参考面快速非接触测量,在普通实验条件下,也可保持良好的稳定性.实验装置即可给出表面的轮廓又可给出其它统计数据,其横向分辨率为1.2 μm,纵向为2 nm.

This paper introduces a new interferometer for measuring the surface roughness based on the principle of differential polarization interferometry. A Faraday modulating system is used to modulate the phase between two interference light beams and the phase is detected by phase-locked interference. It has excellent stability even under normal condition, and rapid and nocontact measurement can be done without a special reference surface. The instrument can produce the surface profile and statistical data with height sensitivity 2 nm and lateral resolution 1.2 μm.