Research On Precision Testing Technology Of Small Optical Aspheric Surface

Using aspheric component in optical system can acquire high imaging quality, improve the optical characteristic, simplify system structure, and minish system volume. Aspheric surface workpiece is hard to manufacture for a long time. Especially testing technology of aspheric workpiece is the bottleneck of manufacturing technology of aspheric surface. Many human and material resources have been put into by experts and specialists over the world in order to studymanufacture and testing technology thoroughly.This paper is derived from National 863 Plan"Non-contacting measurementsensor of 0.1μm", Program for Innovative Research Team in Science and Technologyin Fujian Province University and Project for Technology Innovation of Xiamen University. According to the surface profile measuring of aspheric surface, a new type of testing device with contacting and non-contacting probe is discussed. Technologies of detecting platform building and measurement software designing are studied. In this paper working principle of the testing device is introduced; measurement software modules are designed; systematic errors that may exist are analyzed and mathematics models of these systematic errors are built up. Main efforts are put on analyzing the causes of these errors and how to eliminate them. According to the type of systematic errors, error compensation methods are put forward respectively.Through many experiments that carried out and data processing, this kind of self developed, installation and adjustment testing device of aspheric surface is proved to reach the design requirements of aspheric measurement. After error compensation, measuring data could reflect the real surface profile of the aspheric work piece. The device can fulfill the task of surface profile measuring of fine grinding optical aspheric surface in laboratory and workshop and the accuracy is controlled in±5μm.More important, research results of this paper can improve the detecting efficiency and reduce the cost of aspheric measurement by providing technical support for widespread appliance of aspheric work piece.