子孔径干涉拼接测量非球面的模型分析

针对非球面波前本身带有波前误差的特点和测量中由于装调误差而带来的新的波前误差,提出基于多阶波前误差校准实现子孔径间重叠区不匹配度最小化的方法,建立待拼接的子孔径间相位关系模型;应用逐步回归法确定拼接测量中各波前误差对拼接精度影响的权重,进一步得到优化的子孔径干涉拼接测量（SSI）非球面的测量模型,并且获得较好的波面重构结果。仿真分析表明,理论上该测量模型的拟合精度高于传统测量模型,进一步仿真测量实验表明,基于波像差校准的拼接测量模型能够满足高精密非球面测量的要求。

Model analysis of sub-aperture stitching interferometry for aspheric surface test

Aspheric wavefront is a kind of aberration wavefront relative to the spherical. During asphere surface test, there are some wavefront errors brought by adjustment errors. This paper presents a new method to minimize the mismatch based on calibrating multi-order aberration errors and establishes the phase relationship model for the apertures to be stitched. By using stepwise regress, the weight of effect of wavefront aberration error on stitching accuracy is determined. The asphere measurement model of optimized SSI test is established, and better wavefront reconstruction result is obtained. Simulation analysis shows that theoretically, the fitting precision of the new measurement model is higher than traditional measurement model. Further more, the result of simulation test experiment shows that the new measurement model based on calibrating aberration can satisfy the need of high precision asphere metrology.