为了实现大口径凸非球面镜的高精度检测, 本文研究了凸非球面非零位子孔径拼接检测技术, 并建立了一套非零位拼接检测算法模型, 模型中分别针对同轴子孔径与离轴子孔径非零位检测时所引入的测试误差进行了建模分析, 同时对测试误差剔除、拼接系数求解、全口径面形获得等问题进行了研究。最后, 结合工程实例, 对一口径为130 mm的凸双曲面进行了拼接检测, 分析了该非球面各测试子孔径非零位检测误差形式, 同时进行了误差剔除、全口径面形获取等工作。从拼接结果中可以看出, 拼接结果光滑、连续、无拼接痕迹。为了进一步验证拼接精度, 我们将拼接结果与子孔径检测结果进行对比, 引入了自检验子孔径评价方法, 计算得到自检验子孔径与拼接结果在自检验子孔径范围内的残差图, 二者残差图的PV值与RMS值分别为0016λ与0003λ, 由上述结果可以得到自检验子孔径的测试结果与拼接结果在自检验子孔径范围内是一致的, 从而验证了本文算法的拼接精度。

In order to realize the high-precision detection of large-caliber convex aspherical mirrors, we study the convex aspheric non-null sub-aperture stitching detection technology, and establish a set of non-null stitching detection algorithm model, in which the test errors introduced by non-null detection of the coaxial sub-aperture and the off-axis sub-aperture are modeled and analyzed. At the same time, testing error elimination, stitching coefficients calculation and full-aperture surface acquiring are also analyzed. Finally, combined with actual project, stitching detection of a convex hyperboloid with a diameter of 130 mm is performed. The non-null detection error form of each test sub-aperture of the aspheric surface is discussed, and error elimination, full-aperture surface acquiring and other work are carried out. It can be found from the stitching result that the stitching is smooth, continuous, and there is no stitching trace. To further verify the stitching accuracy, we compare the stitching result with the sub-aperture testing result. The self-test sub-aperture evaluation method is used to calculate the residual map of the self-test sub-aperture and the stitching result in the self-test sub-aperture range. The PV and RMS values of the residual map are 0016λ and 0003λ, respectively. From the above results, it can be concluded that the test results of the self-test sub-aperture and the stitching result are consistent within the self-test sub-aperture range, thus verifying the stitching accuracy of the algorithm.