Study On The Mechanism Of Surface Micro Nano Structure On Optical Properties

The traditional method of antireflection for optical elements is to coat one or more layers of antireflection film on the surface of optical elements to achieve the purpose of antireflection.However,due to the limitations of physical and chemical properties,it leads to thermal mismatch,stability and other problems,which makes this method have some defects.When the eye microstructure of moth is found to have antireflection effect,and the structure has excellent mechanical properties,not affected by physical and chemical properties and other factors,its superior properties reveal the broad application prospects,making it immediately become the focus of many researchers.Therefore,two kinds of surface micro-nano structures,spherical and conical,are directly processed on the optical surface to realize the anti-reflection effect.This paper first introduces several theoretical methods for analyzing and calculating the antireflection of micro-nano structures,strictly coupled wave analysis,moment method,finite difference time domain method,finite element method and so on,moment method,finite-difference time-domain method,finite element method,etc.After that,the micro nano structure of the optical element surface is modeled,and the periodic elements are divided.Finally,the hexagonal period is selected and the feature size is determined.Then,the theoretical process of the analysis is deduced,and the diffraction characteristics of the periodic array with surface micro nano structure are analyzed.In the process of finite element calculation,the diffraction order and direction of the model are analyzed by vector diffraction theory,the electric field strength and magnetic field strength are calculated by finite element method,and the diffraction efficiency is calculated by Floquet theory analysis.At last,two kinds of optical elements are tested in the band of 200nm-900 nm by spectrophotometer.The reflectivity of the optical elements is lower than 600 nm,and the effect of antireflection is improved.The simulation results of the two structures are in good agreement with the experimental data.Therefore,in conclusion,the microstructure of spherical and conical surfaces has an obvious enhancement effect on light transmission.The research results can provide reference for the influence of surface micro nano structure on the optical transmission performance,and for the optimal design and manufacture of micro nano optical devices in the future.