Research On Laser Scattering Microscopic Imaging Detection System For Mirror Surface

As a typical high-precision optical component,high-reflection mirrors directly affect the performance and accuracy of optical test systems.The scattering amount on the surface of the high mirror can be detected by the laser scattering microscopic imaging system.In this paper,the imaging technique is used to measure and evaluate the local solid angle scattering distribution,and further to mark and measure the surface flaw,which is of great significance for the surface research of high mirrors.In order to ensure the detection efficiency and accuracy requirements of the whole system,firstly,on the hardware system,select the laser source and CCD that meets the requirements,design a 20×microscope objective lens,calculate the size of the spot;secondly,in order to get better Scattering images of defects,for the scratches and pitting,focus on the effects of different incident angles of the light source and the difference in scattered light at different azimuth angles of the same incident angle on the imaging quality of the defects,and the relationship between laser irradiation in spatial domain and scattering light imaging of defects is obtained;Finally,a microscopic imaging test software based on Labview was developed,the software controls the rotation angle and position of the high mirror through the stepper motor,and collects the scattering image in real time,focus on how to accurately register and fuse the acquired subaperture images quickly and efficiently,and complete the algorithm design of all subaperture image stitching on the surface of high mirrors.In order to facilitate the processing of the defects image on the high mirror surface,the software framework of the defects image processing system is compiled,which achieved the purpose of efficient detection of defects on the surface of high mirrors.Based on the design of the above software and hardware system,the laser scattering microscopic imaging test system was built,the test system was calibrated with a standard resolution plate with a pitch of 25?m,the calibration results prove that the test system can meet the testing requirements of high mirrors surface defects.Test results of defects information can be obtained by testing the ?5mm area of the high-reflection mirror sample.By analyzing the accuracy of the entire test system,the microscopic defects can be resolved at 20×magnification,and the overall system detection time is less than 10 minutes.