Surface Topography Modeling And Optical Performance Analysis Of Microstructures

As the core optical components,microstructures are widely used in measurement,optical communication and other fields.Its surface quality is an important factor in determining the performance and stability of optical components.However,the shape and size of microstructures are difficult to detect with precision equipment and identify whether the surface topography meets the design requirements.Although some domestic and foreign scholars have carried out related research on the relationship between surface topography and optical performance,they are mainly limited to a single plane or a single curved surface,and there is no correlation between the shape change of the microstructure and the influence of the surface topography on the optical performance.In summary,the establishment of the relationship between the surface morphology of the microstructure and its optical performance is conducive to the rapid and accurate detection of the surface morphology of a large-area microstructure array.This paper takes the corner cube reflector(CCR)as an example to analyze the influence of corner prism bending deformation on the reflective effect.By simulating the rough surface and building a corner cube with topography,the influence of the corner prism surface topography parameters on the reflective effect is studied.The main contents of this thesis are:(1)Based on the principle of volume invariance,the mapping relationship between the CCR bending angle and the dihedral angle of the reflecting surface is established,and the influence of the dihedral angle error and surface shape error of the CCR on its reflective characteristics is analyzed.Based on Kirchhoff’s theory,the influence of random rough surface on optical performance is analyzed,and the relationship between reflected light intensity and rough surface parameters is obtained.Analyze the topography parameters of the processed surface with different processing methods.(2)Use two-dimensional digital filtering technology to simulate random surfaces,select an exponential autocorrelation function that conforms to most of the topography distribution,and use Matlab to generate Gaussian surfaces with a specified root mean square size and different correlation lengths;through Johnson the conversion system converts the Gaussian surface into a non-Gaussian surface with specified parameters(root mean square,kurtosis,skewness and its autocorrelation length);analyzes the error between the input and output surface topography parameters and the autocorrelation function.And the actual surface simulation results show that the simulated surface height distribution is consistent with the actual surface height distribution.(3)Establish a solid model of a random rough surface and a corner cube with surface morphology.Three point cloud reconstruction methods are used to reconstruct the simulated rough surface,compare and analyze the quality of the reconstructed solid surface,and choose the best method for surface reconstruction.On this basis,according to the CCR processing process,the reflecting surface is reconstructed.In order to solve the gap between the reconstructed CCR reflecting surface,the right angle side of the reconstructed reflecting surface is linearized,and the linearized surface is analyzed quality.(4)Perform optical simulation on rough surface,CCR with surface topography and curved CCR.By changing the incident angle of light,the effects of surface parameters root mean square,kurtosis,skewness,autocorrelation length and its bending deformation on the optical performance of CCR were studied,and the relationship between different surface parameters and reflectivity was established.Simulation results shows that the root mean square of the surface parameters has the greatest influence on the reflectivity.