Study On The Directional Enhanced Retro-Reflective Micro Structure Device

Directional retro-reflective devices have good retro-reflective effects,and are widely used in road traffic,body safety signs,night safety warning clothing and other fields.Because its bright reflective effect can effectively enhance the visibility of objects,play a prominent role,and ensure safety.In recent years,with the application of high-performance directional retro-reflective devices in various optical systems and laser design simulators,it has attracted widespread attention in the military field.This article focuses on the research of directional retro-reflective microstructure devices with high reflection regression performance for 808 nm semiconductor laser.Based on the occurrence of retro-reflective phenomenon,based on the optical path of glass micro-beads,the optical path tracing method was used to theoretically analyze the refractive index of glass micro-beads and the characteristics of retro-reflected light when retro-reflection occurred,In order to directionally enhance the retro-reflective performance of open-type retro-reflective devices,glass micro-bead structural units were established.By simulating three refractive index glass micro-beads of 1.93,2.0,and 2.2 on two kinds of substrates(a common substrate with 10% reflectance and reflection The size of the retro-reflective performance on a highly reflective substrate with a rate of 99%)was simulated and analyzed.The results show: Highly reflective substrates can enhance the retro-reflective properties of glass micro-bead retro-reflective microstructure devices.High-reflectivity substrates by plating optical films,based on the results of the simulation analysis,the preparation of a highly reflective optical film substrate at 808 nm was studied.According to the optical characteristics of the material,a reasonable film material is screened.Based on the optical thin film theory,a metal+dielectric structure film system was designed with the help of film system design software.During the film preparation process,optimization of various process parameters that affect the film properties is studied.Finally,a directional retro-reflective microstructure device was prepared in combination with the developed optical film substrate.According to the test results,the main factors that caused the reduction in retro-reflective performance were analyzed,and the preparation process was further optimized and improved.In order to increase the density of glass micro-beads for regression elements,a spin coating method was proposed to complete the preparation of directional retro-reflective microstructure devices.The 1.93 refractive index glass microspheres were selected,directional enhanced retro-reflective microstructure devices were fabricated on the two substrates by the beading method.The surface microstructure of retro-reflective devices was characterized by SEM,and the main factors leading to the reduction of retro-reflective performance were analyzed.Aiming at the non-uniformity of glass microspheres,spin coating was used to preparedirectional retro-reflective microstructure devices,and the preparation process was further optimized and modified.The test results show that the substrate reflectance can be used to enhance the retro-reflective performance of retro-reflective microstructure devices;The retro-reflective microstructure device prepared on the high-reflectivity optical film substrate has a retro-reflectivity of 46.2% when the light is incident perpendicularly,which is 3.6times that of the ordinary substrate;when the incident angle increases to 30°,the retro-reflectivity is 25.5% The ordinary substrate has a retro-reflectivity of zero;Although the actual results are lower than the simulation results,the overall changes are consistent,which can meet the requirements of the 808 nm semiconductor laser for the retro-reflector of the analog system.