用于表面增透的二元光学结构模拟

Binary Optical Structure Simulation for Surface Antireflection

采用退火算法,以台阶模型作为基础,在纯石英玻璃基底上,以光线入射角度0°~70°,波长0.3~1.2μm范围内的s光与p光最小反射率作为优化目标,对单层、4层和6层二维台阶表面结构中的各层厚度和等效折射率进行了优化,得到优化后的各层等效折射率和物理厚度,以二阶等效介质理论为基础计算各层的占空比,得到了由多层台阶组成的表面微结构。同时,分别采用传递矩阵方法和严格耦合波理论计算单层、4层和6层二维表面台阶微结构的表面反射率,对比了二阶等效介质理论和严格耦合波理论方法计算得到的表面反射曲线。使用这一方法设计的多台阶二元光学表面结构具备宽光谱大角度薄膜增透效果,对模拟设计并制备最优性能的表面增透微结构具有指导意义。

Using the annealing algorithm,based on the step model,on the pure fused silica glass substrate,the minimum reflectance of s-light and p-light in the wavelength range of 0.3-1.2μm with the incident angle of light from 0°to 70°is used as the optimization target.The thickness and equivalent refractive index of each layer in the single-layer,4-layer and 6-layer two-dimensional stepped surface structures are optimized,and the optimized equivalent refractive index and physical thickness of each layer are obtained,which are calculated based on the second-order equivalent medium theory.The duty cycle of each layer was determined,and the surface microstructure composed of multi-layer steps was obtained.At the same time,the surface reflectance of single-layer,4-layer and 6-layer two-dimensional surface step microstructures are calculated by transfer matrix method and rigorous coupled wave theory respectively,and the surface reflectance curves calculated by second-order equivalent medium theory and rigorous coupled wave theory are compared.The designed multi-step binary optical surface structure of this method has low surface reflectivity with wide spectrum scale and incident angle of light,and it is useful and significant for guiding the actual preparation process and design of the surface anti-reflection microstructure with optimal performance.