高精度、大口径平面波像差标准──移相式数字平面干涉仪

High Accuracy and Large Aperture Optical Standard ──Phase Shifting Digital Flat Interferometer

介绍研制成的一台移相式数字平面干涉仪，其孔径为Φ２４５ｍｍ，用液面作基准标定并消除仪器的系统误差，准确度优于λ／５０（峰谷值，λ＝０．６３２８μｍ）。利用计算机辅助干涉术，被测件口径可扩展到Φ５００ｍｍ。该仪器将用于建立高精度、大孔径平面波像差标准。文中阐述了光学干涉仪、移相器及精度校核等问题。

This paper describes a large aperture-high accuracy phase shifting digital flat interferometer which is a combination of optics,mechanics,electricity and algorithm.Its aperture is 245 mm and liquid surface is used as absolute flat to eliminate systemic error.The accuracy is better than λ/50 (λ= 0. 6328 μm peak-to-valley value). The tested aperture can be enlarged to 500 mm.This interferometer will be used as an optical flat standard instrument.The optical interfermeter,phase shifter and calibration of precision are discussed.