斐索式红外干涉仪研制和测试技术研究

Research on Techniques of Fabrication and Measurement about Fizeau Infrared Interferometer

研制了斐索式红外干涉仪,口径为120mm,配置F/1,F/4标准球面锗透镜,用于检测红外非球面透镜的非球面面形和波像差质量。干涉仪中采用两个红外探测器分别形成对点、测试两路成像光路,并配合光栅尺,实时监测标准镜和被测件的方位,解决了红外光不可见性带来的测试中装夹调整的困难。采用在线标定的方法,实现了大伸长量移相器的标定。使用干涉仪检测了红外非球面透镜的质量,并标定了系统误差。检测结果表明,干涉仪的测量精度均方根(RMS)值优于0.01λ,测量重复性RMS优于0.002λ。

A Fizeau infrared （IR） interlerometer which can test the quality of aspheric surfaces and wavefront aberration of IR aspheric lens is designed and fabricated. The interferometer with aperture of φ 120 mm comprises F/1 and F/4 standard germanium lens. Two IR detectors are mounted on imaging paths for alignment and measurement, which can be used to monitor orientations of standard lens and elements under test, coupled with raster ruler. The configuration solves the problems of adjustment brought by invisible characteristic of IR light. Phase shifter with great elongation is calibrated by technique of on-line calibration. The quality of IR aspherie lens is measured with the interferometer, and system errors of the interferometer are also tested. Results indicate that the accuracy and repeatability of the interferometer are better than 0.01;t （RMS） and 0. 002λ （RMS）, respectively.