数字莫尔移相干涉仪误差多点标定与修正研究

Interferometry has a high measurement accuracy and a wide range of applications in the existing surface inspection methods of optical components. Fabrication and alignment errors in the interferometer reduces the accuracy of surface inspection. A multi-point calibration method of an actual interferometer system using a Shaker-Hartmann wavefront sensor is proposed. The correction of the virtual interferometer system is implemented in the optical design software ZEMAX using wavefront calibration data. Combined with digital Moiré phase-shifting algorithm, the influence of the fabrication and alignment errors in the actual interferometer are eliminated. A planar mirror and a deformable mirror are selected as the test mirrors for surface shape measurement experiments. The results show that the measurement accuracy of the digital Moiré phase-shifting interferometer system after calibration and correction is improved. Compared with the measurement results of the Zygo interferometer, the surface shapes are consistent and the peak-to-valley (PV) error difference is within 0.07λ (λ=532 nm).