Interference of convergent polarized light to test crystal optical surface

Abstract

Due to properties required of optical elements, it is very important to detect the surface of non-contact object in modern science and technology fields. There are so many methods for detection of object surface, most of which are for isotropic and optical uniform media devices, and mainly utilize optical plane reflection of device under test to obtain. But ones for crystal optical surface are few. The method is put forward to use interference of convergent polarized light to measure optical surface of uniaxial and biaxial crystal in the paper. The basic principle is analyzed that is about interference of polarized light, and the relationship is derivate that is between interference pattern of polarized light formed after spherical light via crystal devices and crystal optical surface. The numerical computation is done by means of MATLAB. Data processing software is programmed. The data relationship is simulated and calculated between interference pattern of polarized light and crystal optical surface. And corresponding curve is plotted out. The testing experimental equipment is designed and set up, which can measure the surface of uniaxial crystal (wave-plate) and biaxial crystal (KTP) whose accuracy may come up to 0.5μm.