子孔径拼接干涉法检测非球面

介绍了子孔径拼接干涉检测非球面的理论和方法,分析了其基本原理,基于齐次坐标变换、最小二乘法和Zernike多项式拟合建立了一种合理的拼接算法和数学模型。对一抛物面镜进行了五个子孔径的计算机模拟拼接实验,拼接前后全孔径面形误差分布是一致的,其PV值和RMS值的偏差分别为-0.009 2 λ和0.0013 λ;全口径相位分布的PV值和RMS值的相对误差分别为-0.39%和0.44%。实验结果表明,利用子孔径拼接技术不需要零位补偿就能实现对较大口径非球面的测量。

Testing asphere by subaperture stitching interferometric method

A subaperture stitching interferometric method was introduced, and the basic principle was analyzed. A reasonable mathematical model and a effective stitching algorithm were established based on homogeneous coordinates transformation, least square method and Zernike polynomial fitting. Meanwhile the computer simulation experiment was carried on with five subapertures for a parabolic mirror, the phase map after stitching is consistent to the inputed map, the difference of the PV and RMS of the full aperture surface error is -0.009 2 λ and 0.0013 λ after stitching, and the relative error of PV and RMS is -0.39% and 0.44%, respectively. The results show that the method is feasible and accurate, and can test large aspheric surfaces without compensators and other auxiliary null optics.