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Design and certification of a null corrector to test hyperboloid convex mirror

Several methods to test high accuracy hyperboloid convex surfaces were introduced. A kind of arrangement was chosen to test a surface with a diameter of 92mm, radius of 280.25mm, and conic k -3.115. A null corrector for testing was developed, which is made up of three thin lenses with designed residual wavefront aberration less than 0.008λ(RMS). The variation of wavefront aberration of the testing system for manufacture, test, assembly and adjustment errors of the null corrector was analyzed. Finally the test result by the null corrector was shown.