Research On Influencing Factors Of Defect Detection Resolution Of Optical Elements

In recent years,high-precision optical elements have been widely used in various large-scale laser optical systems.The quality of laser components affects the improvement of the laser system performance directly.However,restricted to the processing technology of optical elements,it is inevitable that optical components get defects.The defects will affect operation of the entire optical system.Therefore,the requirement for defect detection of optical elements are gradually increasing.The existing defect detection methods of optical elements each have their own shortcomings,and a better method needs to be developed.The optical cavity ring-down technique can accurately detect the ultra-high reflectivity.By using CRD technique,the reflectivity distribution map of the optical element can be obtained.In essence,data in the measured reflectivity distribution map is the convolution result between the light spot and the real defect.A mathematical deconvolution algorithm can be used to make the result more accurate and improve defect resolution.Therefore,this article focuses on the theory about defect detection resolution of optical components and influencing factors,including:(1)Based on the theory about optical cavity ring-down and deconvolution,a method for improving the defect detection resolution of optical elements is studied.Compared with the traditional optical element defect detection methods,deconvolution of the reflectivity distribution map based on optical cavity ring-down scanning technique can improve defect detection resolution.(2)High-reflection laser elements were measured by using the optical cavity ringdown experiment system.The reflectivity figures of high-reflection elements were scanned in one and two dimensions,and the deconvolution algorithm was used to process the data to get the exact reflectivity map of the optical components.(3)An improved deconvolution algorithm was programmed and numerical simulation was performed on MATLAB.This paper proved its correctness from positive side and negative side.The result of numerical simulation demonstrated that the deconvolution method can well process the reflectivity distribution map of the highreflection optical element.The deconvolution algorithm can eliminate the influence of the spot size and effectively improve the accuracy of the detection result.The deconvolution method can make the result closer to the actual reflectivity.(4)The influence of different factors on resolution of defect detection of optical elements was studied.The effect of the spot size on the convolution results was analyzed.The range of defects that can be detected by using a specific light spot was studied.Also,the effect of different scan steps on the deconvolution results was analyzed.