Study On Key Techniques Of Complex Optical Surface Precision Grinding

With the development of demand,the tradition optical elements are difficult to meet the growing performance requirements of optical system.With the advantages such as high freedom,flexible design and ability to improve performance and simplify structure of the optical system,optical elements with complex surfaces have been developed and applied,thus becoming a new generation of optical elements.As the rough machining part of optical manufacturing,precision grinding is greatly challenged when facing with complex optical surface elements,and lots of key techniques need to be solved urgently.This paper focuses on the theme of surface accuracy control in the grinding of complex surface,and theoretical modeling and experimental verification are carried out to conduct research in several aspects,with the purposes to get a further understanding of the difficulty in precision grinding of complex surface and solve some key technical problems.The main research work of this paper includes the following aspects:1.Modeling for the grinding of complex surface.The grinding process of complex surface is analyzed,and the mathematical model for grinding is established based on the normal vector matching principle.To make full use of the grinding model,it is applied to analyze the grinding process,calculate coordinates of the tool position point,detect and eliminate interference,conduct modeling and simulation of influencing factors on the surface form error,and so on.2.Study on key control techniques of form and position accuracy for the grinding of complex optical surface.Modeling and simulation for scallop-height and linear approximation error are conducted,and the influences of step pitch,path interval,shape and size of grinding wheel and surface gradient are studied,and the analysis results are used to optimize process parameters for grinding.In order to study the influence of grinding wheel on complex optical surface grinding,modeling and simulation of radius error,arc form error and wear of grinding wheel are conducted respectively,and the theoretical analysis results are verified by a series of experiments.Compensation method for surface form error is put forward and different compensation modes are compared.Surface form error caused by position error is analyzed to guide workpiece localization and according to the surface matching process,a method to control surface position error is presented.After compensation grinding,the PV value and RMS value of the complex convex surface are 5.01?m and 0.84?m respectively;and as for the complex concave surface,the results are 7.03?m and0.94?m respectively.3 Study on the precision grinding technological process of complex optical surface.Based on the overall research content,the grinding technological process is established by summarizing research ideas,process route and other important factors.According to the grinding technological process,a complex optical surface is machined and the good experimental results prove the correctness of grinding technological process and research content.