Design and fabrication of computer-generated holograms for testing optical freeform surfaces

作     者：沈华 朱日宏 高志山 E. Y. B. PUN W. H. Wong 朱效立 

作者机构：School of Electronic Engineering and Photo-Electric Technology Nanjing University of Science and Technology Department of Electronic Engineering City University of Hong Kong Key Laboratory of Nano-Fabrication and Novel Devices Integrated Technology Institute of Microelectronic of Chinese Academy of Sciences 

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

年 卷 期：2013年第11卷第3期

页      面：64-68页

核心收录：

学科分类：0808[工学-电气工程] 080901[工学-物理电子学] 0809[工学-电子科学与技术（可授工学、理学学位）] 08[工学] 080401[工学-精密仪器及机械] 0804[工学-仪器科学与技术] 0805[工学-材料科学与工程（可授工学、理学学位）] 0803[工学-光学工程] 0702[理学-物理学] 

基　　金：supported by the Natural Science Foundation of Jiangsu Province of China under Grant No.BK2012802 

主　　题：Computer generated holography Design Electron holography Optical systems 

摘      要：Freeform optical surfaces （FOSs） will be the best elements in the design of compact optical systems in the future. However, it is extremely difficult to measure freeform surface with sufficient accuracy, which im- pedes the development of the freeform surface. The design and fabrication of computer-generated hologram （CGH） , which has been successfully applied to the tests for aspheric surfaces, cannot be directly adopted to test FOSs due to their non-rotational asymmetry. A novel ray tracing planning method combined with successively optimizing even and odd power coefficients of phase polynomials in turn is proposed, which can successfully design a non-rotational asymmetry CGH for the tests of FOSs with an F-O lens. A new eight-step fabrication process is also presented aiming to solve the problem that the linewidth on the same circle of the CGH for testing freeform surface is not uniform. This problem cannot be solved in the original procedure of CGH fabrication. The test results of the step profiler show that the CGH fabricated in the new nrocedure meets the reauirements.