Cutting Process Experiment And Thermal Error Compensation Research Of Optical Microstructure On Roller Mold

With the rapid increase of global demand for optoelectronic products and the development of innovative technologies such as glasses-free 3D technology,the demand for optical devices,one of the key components of the photoelectric system,has gradually increased.Meanwhile,the technical requirements are also constantly increasing.So the manufacturing technology of large area,high surface quality and high dimensional accuracy of the optical microstructure array has become one of today’s research hotspots.Roll-to-Roll copy machining technology has gained the attention of scholars from various countries for the advantages of high precision,high efficiency and low cost,and has been widely studied.Our group developed the initial domestic roller mold ultra-precision machine.A systematic study is carried out from the hardware equipment of the machine to the processing technology.In this thesis,process parameters influence on the surface quality of optical microstructures is studied,reason of pitch error caused by thermal field distribution is explained,and a error compensation system is designed to improve the precision of optical microstructure.Firstly,we study the influence factors of the surface quality of the optical microstructure processed by the roller mold ultra-precision machine.The model of cutting force applied to the processed optical microstructure is given by theoretical deduction,whose accuracy has been verified by the cutting force experiment.In order to obtain better optical microstructure surface quality,the dynamic performance of the machine is debugged.The influence of cutting parameters on surface roughness of optical microstructure is given by co MParing the experimental results and the causes are analyzed by the cutting force model,obtaining the reasonable cutting parameters of microstructure array machining.Then we finished the processing experiments of dot array,translot and chute.Secondly,aiming at the problem of the sudden change of the pitch at the closing position found in the whole circle horizontal groove microstructure processing,the causes of the error are analyzed in detail.In order to improve the machining accuracy for the optical microstructure,the thermal deformation analysis of the linear guideway system for the roller mold ultra-precision machine is carried out.The thermal power generated by the heat source of the hydrostatic guide system is calculated.According to the structural characteristics of hydrostatic guideway,an equivalent method of oil film in finite element analysis is presented and the finite element analysis model is established.The thermal-structure coupling analysis of the linear guideway system of the machine tool is carried out by using the finite element software.The thermal deformation error of linear guideway system is obtained.The method to improve the machining accuracy of the optical micro structure of the roller mould machine is presented.The analysis results show that the main reason for the large pitch error at the closing position is the thermal error of the machine tool.Finally,according to the cause of pitch error,the compensation of pitch error is studied from two aspects of control system and processing technology.From the perspective of the control system,the hardware and software of the error compensation system are designed and the error compensation system is verified by experiments.From the perspective of process,the influence factors of pitch error of optical microstructure processing are studied and the pitch mutation at the closing position is analyzed,obtaing the method for reducing the pitch error at the closed area.In order to verify the correctness of the pitch error compensation study,the error compensation system and the analytical method are applied to the microstructure broach to carry out the verification process experiment.And the array of microstructure of the whole circumference surface with high pitch accuracy is obtained.