SPG-1型激光数字波面干涉仪干涉系统的设计、制造与装调

The Design,Fabrication,Assembly and Alignment of Interference System of SPG-1 Type Laser Digital Wavefront Interferometer

已经研制成功的SPG-1型激光数字波面干涉仪是激光技术、微机技术与干涉仪相结合而形成的一种新型光学面形的测试仪器。本文概述该仪器的设计指标及其依据,干涉系统的设计要求,设计结果,关键干涉元件的制造以及干涉系统的装调。仪器的最大口径为φ80mm,最高测量精度为λ/40,分辨率为λ/100,球面测量范围为500mm曲率半径以内.可以测量A级光学样板。干涉系统应有低的噪音、高的干涉条纹对比度及条纹亮度可调等要求。所采用的菲索型与泰曼型的干涉系统中,引入偏振元件而形成偏振干涉系统较好地满足了上述要求。仪器的自检误差优于0.04λ。为了使SPG-1型数字干涉仪及早产品化,提出了一个组合式的设计方案。

The Successfully developed SPG-1 laser digital wavefront inter-ferometer is a new type of instrument for measuring the optical surfaces, whichcombines the laser technique、the minicomputer technique and interference tech-nique. This paper covers the design indices and their basis, the design require-ments and design results, the fabrication of the key elements of the interfero-meter, and also the assembly and alignment of it's interference system. The maximum aperture of the instrument is φ80 mm, the highest precisionof measurment is λ/40, the resolution is λ /100. The range of measuring theradius of curvature for A-grade optical spherical test plate is within 500 mm.A interference system should have low noise、high contrast and adjustable bri-ghtness of the fringes. In the Fizeau and Twyman-Green interference systemused, polaroid elements are introduced to form polarization interference systemso that the above requirements can be satisfied rather well. System error is lessthan λ/25. In order to industrialize this digital interferometer, a combinationdesign schemc is proposed.