摘要
In order to solve tile difficulty of testing large mirror, the sub-aperture stitching interfhrometry （SSI） is proposed and expatiated. Tile basic theory and principle of this method are introduced and analyzed. A reasonable stitching algorithm a.nd mathematical model are established based on least-squares fitting, triangulation algorithm, homogeneous coordinate transformation, etc., and the relative program and flow chart are established. Some marked points are used to accomplish the alignments between sub-apertures and calibrate the relationship between the coordinate of the mirror and the pixeh With engineering examples, a large rectangular mirror with an irregular aperture of 720×165 （mm） is tested by SSI. The peak-to-valley and root mean square of the stitched surface error are 0.451 λ and 0.042 ）λ （λ is 632.8 nm）, respectively.
In order to solve tile difficulty of testing large mirror, the sub-aperture stitching interfhrometry （SSI） is proposed and expatiated. Tile basic theory and principle of this method are introduced and analyzed. A reasonable stitching algorithm a.nd mathematical model are established based on least-squares fitting, triangulation algorithm, homogeneous coordinate transformation, etc., and the relative program and flow chart are established. Some marked points are used to accomplish the alignments between sub-apertures and calibrate the relationship between the coordinate of the mirror and the pixeh With engineering examples, a large rectangular mirror with an irregular aperture of 720×165 （mm） is tested by SSI. The peak-to-valley and root mean square of the stitched surface error are 0.451 λ and 0.042 ）λ （λ is 632.8 nm）, respectively.
基金
This work was supported by the National High Technology Research and Development Program of China （No. O8663NJ090） and the National Natural Science Foundation of China （No. 61036015）.
