Aspheric surface measurement based on sub-aperture stitching interferometry

作     者：王孝坤 

作者机构：Key Laboratory of Optical System Advanced Manufacturing Technology Changchun Institute of Optics Fine Mechanics and Physics Chinese Academy of Sciences Changchun 130033 China 

出 版 物：《Chinese Optics Letters》 (中国光学快报（英文版）)

年 卷 期：2013年第11卷第14期

页      面：59-62页

核心收录：

学科分类：08[工学] 082701[工学-核能科学与工程] 0827[工学-核科学与技术] 0803[工学-光学工程] 

主　　题：120.6650 Surface measurements, figure 120.0120 Instrumentation, measurement, and metrology 240.0240 Optics at surfaces 

摘      要：In order to test convex aspheric surfaces without the aid of other null optics, a novel method combined sub-aperture stitching and interferometry called SSI （sub-aperture stitching interferometry） is introduced. In this letter, the theory, basic principle, and flow chart of SSI are researched. A synthetical optimization stitching mode and an effective stitching algorithm are established based on homogeneous coordinate＇s transformation and simultaneous least-squares fitting. The software of SSI is devised, and the prototype for testing of large aspheres by SSI is designed and developed. The experiment is carried out with five sub- apertures for a convex silicon carbide （SIC） aspheric mirror with a clear aperture of 130 ram. The peak-to- valley （PV） and root-mean-square （RMS） error are 0.186 λand 0.019 λ, respectively. For the comparison and validation, the TMA system which contained the convex asphere is tested by interferometry. The wavefront error of the central field of the optical system is 0.068 λRMS which approaches to diffraction limitation. The results conclude that this technique is feasible and accurate. It enables the non-null testing of aspheric surfaces especially for convex aspheres.