将子孔径拼接技术与干涉技术相结合提出了一种新的检测离轴非球面的方法，该方法无需其他辅助光学元件就可以实现对大口径、离轴非球面的测量.对其基本原理进行了分析和研究；并基于齐次坐标变换、最小二乘拟合建立了综合优化和误差均化的拼接数学模型；开发了子孔径拼接检测非球面的算法软件，并设计和搭建了子孔径拼接干涉检测装置；利用综合优化的拼接模型对一口径为376×188 mm2的离轴非球面进行了拼接干涉测量，通过子孔径拼接算法得到了精确的全口径面形分布；且对该非球面进行零位补偿测量，其全口径面形与拼接全口径面形是一致的，面形分布的PV值和RMS值的偏差仅为0.047λ和 0.006λ.从而提供了除零位补偿检测外另一种定量测试大口径非球面以及离轴非球面的手段.

In order to test large and off-axis aspheric surfaces without the aid of other null optics,a new method subaperture stitching interferometry(SSI) is introduced.The basic principle of the technique is analysed,and the synthetical optimization stitching model and effective stitching algorithm are established based on homogeneous coordinates transformation and simultaneous least-squares method.The stitching software and prototype for testing of large aspheres by SSI are devised and developed.An off-axis asphere with the aperture of 376×188 mm2 is tested by this method.For the comparison and validation,the asphere is also tested by null compensation,the synthesized surface map is consistent to the entire surface map from the null test,and the difference of PV and RMS error between them is 0.047λ and 0.006λ,respectively.So it provides another quantitive measurement for testing large aspheric surfaces and off-axis aspheres besides null-compensation.