利用相移片实现激光自准直的新方法

New Methods for Laser Beam Autocollimation Using Phase Shifting Plate

介绍两种实现激光自准直的方法和实验．阶梯相移片法的特点在于巧妙地利用相移片对入射光进行调制，实现高精度激光自准直和角度的测量，微点相移片法是比较入射光与反射光通过相移点的衍射图形，达到激光自准直的目的。用夫琅和费标量衍射理论分析和计算了激光经过两种相移片调制后的光能分布，并对制作公差进行了讨论。

Two methods and their experiments for laser beam autocollimation areintroduced, the phase step method is based on spatially modulating the incident laser beamby a phase step plate3 and the phase dot method, by passing through the phase dot, thediffraction phenomena of both incident beam and reflected beam are utilized. Theintensity distribution modulated by both phase shifting plate are analyzed based onFraunhofer scalar diffraction theory. The experimental results are presented as well.