为提高红外材料光学表面的抗反射能力, 设计了一种具有双周期嵌套式结构抗反射超表面。通过分析在双周期嵌套式结构周围的介电常数ε变化情况, 仿真模拟得到反射率。重点分析了当微纳结构发生变化时这种嵌套结构与单一结构表面抗反射特性的差别。通过改变嵌套结构表面占空比、顶底端直径比以及长径比等参数仿真模拟, 对抗反射特性进行分析, 最终优化出的结构在2.4~12 μm的超宽波长范围内反射率均低于3.5%, 在中长波实用波段范围内平均反射率低于1%。这种结构有效地保护了微结构形貌不被破坏, 实现了单一结构抗反射特性效果的叠加, 进一步降低了元件表面的反射率, 可以作为一种新型的减反增透表面应用于红外窗口。

In order to improve the anti-reflection ability of the optical surface of infrared materials, an anti-reflection super-surface with a double-cycle nested structure was designed. By analyzing the variation of the dielectric constant ε around the two-cycle nested structure, the reflection efficiency of the double-cycle nested structure was obtained by simulation. The difference between the anti-reflection characteristics of this nested structure and the surface of a single structure was analyzed when the micro structure changed. By changing the surface duty ratio of the nested structure, the diameter ratio of the top and bottom ends, and the aspect ratio simulation, the anti-reflection characteristics of the double-period nested microstructure surface were analyzed, and the double-cycle nesting was finally optimized. The structure could effectively improve the anti-reflection effect in the ultra-wide wavelength range of 2.4-12 μm, the reflectance was below 3.5%, and the average reflectance was less than 1% in the practical band range of mid-long infrared wave. The structure effectively protects the micro-structure from damage, realizes the superposition of the anti-reflection characteristics of the single structure, further reduces the reflectivity of the surface of the component, and can be applied as a novel anti-reflection surface in the infrared window.