Abstract. Antireflective nanostructured surfaces (ARSS) enhance optical transmission through suppression of Fresnel reflection at boundaries between layered media. Previous studies show that random ARSS (rARSS) exhibit broadband enhancement and polarization insensitivity in transmission when applied to flat optical windows. Zinc selenide windows with rARSS treatment were fully characterized (transmittance, reflectance, and angular scatter) in the midwave and long-wave infrared range (2 to 12 μm). Four morphologically different, random nanoroughness, antireflective surfaces were tested at: normal incidence transmission, at 15 deg angle of incidence, and 15 deg to 45 deg angle of reflection. The angular reflectance distribution resembles a diffuse dipole radiator due to the finite elongated beam cross section at the incidence surface. Scattering diagrams with main and side lobes are presented. Partially integrated scatter values were obtained, allowing the comparison of random antireflective boundary performance to optically flat surfaces. Comparing axial transmission and specular reflection with the scattered performance, an accurate determination of the redistribution of the incident energy is obtained. Measurements of the rARSS feature topology were determined from autocorrelation of the scanning electron microscope images of the nanoroughened substrates, to assess the structured surfaces’ feature scales. The results show differences in scattered intensity over the wavelength bands of interest, correlating with surface random feature populations.

中文翻译：

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抑制反射率的纳米结构表面的窄角散射

摘要。抗反射纳米结构表面 (ARSS) 通过抑制分层介质之间边界处的菲涅耳反射来增强光学传输。先前的研究表明，当应用于平面光学窗口时，随机 ARSS (rARSS) 在传输中表现出宽带增强和偏振不敏感性。使用 rARSS 处理的硒化锌窗在中波和长波红外范围（2 至 12 μm）中得到了充分表征（透射率、反射率和角散射）。四种形态不同的随机纳米粗糙度抗反射表面在以下条件下进行测试：垂直入射透射、15 度入射角和 15 度至 45 度反射角。由于入射表面的有限细长光束横截面，角度反射分布类似于漫射偶极辐射器。提供了具有主瓣和旁瓣的散射图。获得了部分积分的散射值，允许将随机抗反射边界性能与光学平坦表面进行比较。将轴向透射和镜面反射与散射性能进行比较，可以获得对入射能量重新分布的准确确定。rARSS 特征拓扑的测量由纳米粗糙基底的扫描电子显微镜图像的自相关确定，以评估结构化表面的特征尺度。结果显示在感兴趣的波段上散射强度的差异，与表面随机特征种群相关。允许将随机抗反射边界性能与光学平坦表面进行比较。将轴向透射和镜面反射与散射性能进行比较，可以获得对入射能量重新分布的准确确定。rARSS 特征拓扑的测量由纳米粗糙化基材的扫描电子显微镜图像的自相关确定，以评估结构化表面的特征尺度。结果显示在感兴趣的波段上散射强度的差异，与表面随机特征种群相关。允许将随机抗反射边界性能与光学平坦表面进行比较。将轴向透射和镜面反射与散射性能进行比较，可以获得对入射能量重新分布的准确确定。rARSS 特征拓扑的测量由纳米粗糙化基材的扫描电子显微镜图像的自相关确定，以评估结构化表面的特征尺度。结果显示在感兴趣的波段上散射强度的差异，与表面随机特征种群相关。rARSS 特征拓扑的测量由纳米粗糙化基材的扫描电子显微镜图像的自相关确定，以评估结构化表面的特征尺度。结果显示在感兴趣的波段上散射强度的差异，与表面随机特征种群相关。rARSS 特征拓扑的测量由纳米粗糙化基材的扫描电子显微镜图像的自相关确定，以评估结构化表面的特征尺度。结果显示在感兴趣的波段上散射强度的差异，与表面随机特征种群相关。