Research On Ultra-precision Grinding Technology Of Hard And Brittle Materials Micro Lens Array

With the continuous development of science and technology,human beings have begun to learn more deeply from nature.Bionics is a typical example.The microlens array imaging system is a micro-optical imaging system that has been proposed to mimic the compound-eye imaging principle of insects in nature.However,the processing of micro-components has always been a challenge to existing science and technology.The existing processing methods are generally divided into special processing technology and ultra-precision machining technology.In terms of dimensional accuracy,ultra-precision machining has natural advantages.A three-axis linkage generating ultra-precision grinding method is used to achieve high-precision grinding of planar rectangular microlens array.In this paper,the abrasive particle kinematics model is established,and the trajectory of the abrasive grain is analyzed.The grinding wheel speed and the workpiece rotation speed will have a major influence on the surface morphology of the workpiece.When the ratio of the grinding wheel speed to the workpiece speed is large,the surface of the workpiece will form a radial shape.According to the characteristics of the planar rectangular microlens array,an indexing grinding trajectory planning scheme is proposed,which can reduce the workload of machining program writing and shorten the processing time.The single-factor grinding experiment was used to determine the grinding process parameters.The single-factor experimental results show that when the grinding wheel speed is constant,the lower the workpiece rotation speed,the smaller the surface roughness of the workpiece.The grinding of the 9×9 planar microlens array is realized,and the surface roughness of the lens unit detected by the white light interferometer is between 5 nm and 20 nm.The lens unit depth was measured in-situ using the self-built lens unit depth measurement platform.The vector value of the microlens array unit was obtained,the vector height design value was 4.8 ?m,and the processed microlens array unit vector height was 4.51 ?m with a variance of 13.4.The main factors affecting the dimensional consistency were analyzed,and the main cause of the inconsistent lens unit size was the wear of the grinding wheel.