Testing large aspheric surfaces with complementary annular subaperture interferometric method

Annular subaperture interferometric method has provided an alternative solution to testing rotationally symmetric aspheric surfaces with low cost and flexibility. However, some new challenges, particularly in the motion and algorithm components, appear when applied to large aspheric surfaces with large departure ill the practical engineering. Based oil our previously reported annular subaperture reconstruction algorithm with Zernike annular polynomials and matrix method, and the experimental results for all approximate 130-mm diameter and f/2 parabolic mirror, all experimental investigation by testing an approximate 302-mm diameter and f/1.7 parabolic mirror with the complementary annular subaperture interferometric method is presented. We have focused on full-aperture reconstruction accuracy, and discuss some error effects and limitations of testing larger aspheric surfaces with the annular subaperture method. Sonic considerations about testing sector segment with complementary sector subapertures are provided.