激光防护是一种可广泛应用的技术,论文针对目前红外激光防护技术中存在的可见光波段吸收强、镜面反射造成设备或人员损伤等问题,提出一种形成于光学窗口表面的红外激光非镜面反射光学微结构,具有对可见光透过率影响小,同时对1 064 nm红外激光大角度散射的功能,从而实现激光防护。文中采用光线追迹方法设计具有移位结构的双面微柱透镜阵列,阵列周期T与透镜单元曲率半径R之间需满足0〈T〈R/2√7的关系。应用Virtual—Lab光学建模软件对设计的柱面微结构进行模拟,模拟结果为:可见光平均透过率下降7%,对实用结果影响很小,并可以通过可见波段镀制增透膜进行弥补;1064nm红外激光反射率约为75%,发散角大于30°。采用数字掩模光刻技术完成微柱透镜阵列实验,实验结果与模拟结果趋势相同,最终得出结论:微柱透镜阵列能实现大角度散射,能够极大降低激光单一方向反射回波能量,从而达到了激光防护的目的。
Laser protection is a technology of wide application, Aimed at the problem that strong absorption in visible wavelengths and equipment or operator injury caused by laser high-reflective film specular reflection exist in infrared laser protection technology, an infrared laser non-specular reflection optical micro-structure formed on optical material surface was presented. It had little effect on visible light transmission and large-angle scattering to 1 064 nm laser. Light track method was used to design double-side micro-cylindrical lens arrays with a dislocation construction. Array period T and curvature radius of lens units R should meet the condition: O〈T〈R/2 √7. Virtual-Lab optical modeling software was applied for the simulation of designed micro-cylindrical lens arrays. The results is that, average transmittance rate of visible light drops 7%, which has little impact on practical result, and which can be made up by visible wavelengths fabrication antireflection coating; 1 064 nm infrared laser reflection is greater than 75%, divergence angle is greater than 30°, Fabrication experiment of micro-cylindrical lens arrays was finished by digital mask lithography technology, the test result was similar to simulation result. The conclusion is that, micro-cylindrical lens arrays can cause wide-angle scattering, which greatly reduces the single-directivity reflection echo energy of laser to achieve the purpose of laser protection.