Research On CGH Aspheric Testing Technology Based On SLM

In the fields of the optical research, non-spherical optical elements have been widely used in modern optical system, because they can reduce the size of system, cut down the weight of equipment, improve optical performance and the images quality. However, the non-spherical technology has been largely restricted for itself testing methods, because it can not be achieved by a simple, efficient and quick testing process.Computer-generated hologram (CGH) doesn't dependent on the advantages of standard aspheric, and the incomparable real-time of the spatial light modulator (SLM). offers possibility for testing aspheric surface with the method of simple, efficient and accurate. Therefore, the paper mainly studied real-time aspheric testing technology based on computer-generated hologram. The paper divides into six parts:The first part of the paper describes the existing test status of aspheric surface in domestic and foreign, and confirms the contents and the key of the subjects; The second part of the paper analyses the test method of aspheric surface at present, and meanwhile focuses on the traditional CGH test method of aspheric surface; The third part of the paper emphasizes on the influence of the pixel structure and respectively test the phase and amplitude modulation characteristic of the SLM on the basis of discussing the optical properties of SLM and its application. Part four researched on the CGH coding method which matches the SLM. the kinoform or phase hologram, and in view of the different phase encoding algorithm, discusses its characteristics; Part five discusses the real-time aspheric surface testing technology program, and based on the ZEMAX optical design software, acquires CGH parameters which matches the measured aspheric surface and finished CGH coding. The optimal result shows that the optimal model effectively solves the problems that is hard to producing the standard wave surface to overlap and interfere with the reference beam in real-time aspheric surface testing; Part six summarizes and prospects the subject work.The paper takes the aspheric surface testing technology as the background, and the holographic technology as backing, do a detailed analysis and research on several key techniques in real-time testing process of aspheric surface. The research provides the reliable theory foundation and experimental basis for real-time testing of aspheric surface.