半导体双波长透射式红外干涉仪的研制及应用

采用635nm波长半导体可见光激光和10.5μm波长半导体红外激光作为干涉光源,设计了635nm和10.5μm双波段共光路透射式红外干涉仪,实现了可见光波段干涉测试与红外光波段干涉测试共光路,且双光路共用可见光对准。双波段共用机械式相移系统,并采用635nm测试光分段驻点标定10.5μm测试时相移器的长行程误差。研制的双波长红外干涉仪系统的红外测试精度达到PV优于0.05λ,RMS优于0.02λ,系统重复性RMS优于0.001λ。采用该干涉仪测试口径为400mm×400mm,离轴量为800mm的离轴非球面,得到边缘最大偏差值为21.9μm,能够实现大口径离轴非球面从粗磨到精磨高精度加工面形的全过程干涉测试。

Fabrication and application of dual-wavelength infrared transmission-type interferometer

A 635 nm and 10.5 μm dual-band coherent optical infrared transmission interferometer was designed. This integrated system employs a visible semiconductor laser at 635 nm and an infrared semiconductor laser at 10.5 μm as the interference light source. Through tests with this integrated system, a common optical path between the interference of the visible light band and the infrared light band could be determined. The common mode of the mechanical phase shift system and the visible light co-alignment were used in the dual-band optical path, and the phase shifter long-stroke error was calibrated at 10.5 μm based on the segment stagnation point of the 635 nm testing light. The accuracy of the developed dual-wavelength infrared interferometer system was measured, where the values of PV, RMS, and RMS repeatability were better than 0.05λ, 0.01λ, and 0.001λ, respectively. The interferometer was used to test an aspherical mirror with off-axis amount of 800 nm and dimensions of 400 mm×400 mm, where the maximum deviation of the measured edge value is 21.9 μm. Furthermore, the interferometer enables high-accurate surface measurements during the entire grinding process of large-aperture off-axis aspheric components.