Study of the Tests of Large-aperture and Fast Focal Ratio Convex Hyperboloid Mirrors with a "Stitching"Method

Based on analyzing and comparing conventional testing methods for large-aperture convex aspheric mirrors, a new methodology is proposed to solve the problem of excessively large aperture of the standard spherical mirror which is used in a traditional Hindle test.There are two Hindle tests in this new method:one is used to test the inner zone of a convex mirror, the others is used to test the outer zone.Each test requires a much less aperture of standard mirror as compared to a single Hindle test of the entire convex mirror.The data for the two areas are combined with a suitable algorithm to derive the surface shape of whole mirror"stitching".In this paper, the principle of the method and algorithm of the stitching are discussed.The results of an experiment show the feasibility of the new method.