全视场外差移相双波长干涉面形检测技术

双波长干涉检测技术可以实现高动态范围与高测试精度的兼顾，是一种极具潜力的检测技术，用于干涉检测的压电位移机械移相技术存在着一些问题，使用全视场外差移相技术，低频差的外差光源与面阵探测器采集帧率相配合，相较于传统的压电位移机械移相技术，可以同时保证不同波长的移相精度，简化移相的复杂度，且可以方便实现多步移相。提出了全视场外差移相双波长干涉测量技术，并搭建了全视场外差移相双波长干涉测量系统，测试了在边缘最高偏离顶点球13 μm的非球面以及高度为(1.3±0.1) μm的台阶，经过实验验证其非球面面形PV测试精度为λ/3.53 (λ=633 nm)，面形PV测试重复精度为λ/77.38，面形RMS测试精度为λ/14.16，面形RMS测试重复精度为λ/919.10，台阶高度测试精度为λ/16.19，测试重复精度为λ/311.85。

Full-field heterodyne phase shifting two-wavelength interferometry surface testing technologies

Because of its high dynamic range and high accuracy, two-wavelength interferometry has great potential, but there are some problems with the use of piezoelectric phase shifting technology, compared with the conventional piezoelectric phase shifting technology, in full-field heterodyne phase shifting technology, the heterodyne light source with low frequency difference can easily realize multi-step phase shifting algorithm, simplify the procedure of phase shifting, ensure the phase shifting accuracy of different wavelengths at the same time. A full-field heterodyne two wavelength phase shifting interferometry is proposed and a full-field heterodyne two wavelength phase shifting interferometer system is built, an aspheric mirror with maximum deviation of 13 μm at the edge and a step with a height of (1.3±0.1) μm is tested. With some experiment tests, the PV error is λ/3.53 at 633 nm wavelength, the PV repeatability is λ/77.38, the RMS error is λ/14.16, the RMS repeatability is λ/919.10 when testing the aspheric mirror and the height error is λ/16.19, the height repeatability is λ/311.85 when testing the step.