Research On CNC Processing Technology Of Silicon Aspheric Surface

On the medium wave infrared(3-5um)band,Silicon single crystal with a very low absorption rate,high refractive index and low dispersion and high hardness,excellent characteristics of infrared optical lens an ideal material for making silicon manufacturing.For a long time silicon single crystals has not been widely used in aspherical infrared lens element.This is due to the characteristics of a silicon single crystal of brittle hard,so that the silicon lens during processing of low processing efficiency,precision is not high,becoming the main reason for restricting the silicon lens production.In this paper,according to commonly used medium-diameter Silicon aspheric lens,based on Preston theory,using CNC grinding and polishing machine to study the ?41 Silicon lens.By combining flexible polishing mould with small-caliber polished mould,CNC polishing for Silicon aspheric surface.In this paper,a lot of tests on the whole process,especially CNC grinding,and polishing process,conducted in-depth and particular research.The main impact on the abrasive wheel size,abrasive wheel speed,axle revolving speed,feed rate and other non-spherical grinding parameters were studied;Research by polishing cloth types,polishing speed,vector angle,pressure and other factors of aspheric polishing parameters were studied.Through continuous optimization,arrive at the most suitable combination of processing parameters.We got to meet the requirements of the silicon aspheric surface.Improve the processing accuracy and processing efficiency,we have the ability to batch production silicon aspheric lens.