Research On Removal Characteristics And Control Techniques Of Intelligent Polishing Methods

Aspheric optical lenses with high form accuracy have been widely used in the high-tech fields such as laser fusion, large astronomical telescope, digital audio-video equipment, medical instrument and optical fiber communication, since the application of aspheric optical lenses can obtain high quality of graphic effects and optical properties. For this reason, the precision manufacturing techniques of aspheric optical lens have been concerned by a lot of countries. And polishing as the final step of precision manufacturing procedures is the basis for obtaining fine surface texture and roughness of aspheric optical lens. At present, intelligent polishing techniques controlled by computer have been adopted in optical lenses polishing. Therefore it is very necessary to strengthen the study of intelligent polishing techniques to improve polishing accuracy and efficiency.According to the characteristic of intelligent polishing techniques, key technical research on intelligent polishing have been conducted to improve polishing accuracy and efficiency, mainly including analysis of material removal characteristic, optimization of motion control algorithm, software development and polishing experiments. The main work in this paper is as follows.(1) The models of removal function have been established based on the removal mechanism of three kinds of polishing methods, CCOS, CCAL and bonnet polishing. And then the analysis of correction ability of spatial frequency error is investigated through Fourier transformation of established removal function models.(2) The movement control model for bonnet tool polishing is presented in order to process non-axisymmetric aspheric lenses with precession. And then some simulations are carried out to verify the movement model and control algorithm.(3) A new polishing path based on Prim algorithm is put forward to improve polishing efficiency, by comparative analysis of motion characteristics of raster path and spiral path.(4) The process control software of intelligent polishing has been developed, including the function, interferometric data result input and data processing, polishing parameters setting, polishing path generation and NC program output.(5) Polishing experiments are carried out to support the theoretic work presented in this paper.