Experimental study on subaperture stitching testing of convex hyperboloid surface

We propose a non-null subaperture stitching method to measure the convex aspheric surfaces. In the method, the non-null configuration avoids the introduction of auxiliary optical elements which must be specially designed and customized, and their compensating effects cannot be independently measured. In order to obtain the full aperture result, a non-null stitching algorithm based on ray tracing method and least square method is developed to stitch all phase data together. Both simulation and experimental results justify the proposed method.