本文采用溶胶-凝胶法制备了SiO₂增透膜，然后对其进行等离子体结合六甲基二硅胺烷（HMDS）表面改性处理。研究了后处理改性对增透膜表面形貌、微观结构、光学性能及激光损伤性能的影响规律，获得了抗真空有机污染的二氧化硅增透膜。结果表明，增透膜在采用等离子体结合HMDS表面改性处理后，膜层收缩、粗糙度下降、极性羟基等有机基团含量减少；两步后处理改善了增透膜膜层结构和光学性能，显著提高了膜层疏水能力和真空条件下的抗污染性能，并且对溶胶-凝胶二氧化硅增透膜的高损伤阈值属性不产生影响。

Boron nitride (BN) nanosheets incorporated silica antireflective (AR) coating was successfully prepared on fused silica substrate to improve the antilaser-damage ability of transmissive optics used in high-power laser systems. The BN nanosheets were obtained by urea assisted solid exfoliation, and then incorporated into basic-catalyzed silica sols without any further treatment. The transmission electron microscope (TEM) images indicated that the BN nanosheets generally consisted of 2–10 layers. The antireflective BN/$\text｛SiO｝_｛2｝$ coating exhibited excellent transmittance as high as 99.89% at 351 nm wavelength on fused silica substrate. The thermal conductivity $0.135~\text｛W｝\cdot \text｛m｝^｛-1｝\cdot \text｛K｝^｛-1｝$ of the BN/$\text｛SiO｝_｛2｝$ coating with 10% BN addition was about 23% higher than $0.11~\text｛W｝\cdot \text｛m｝^｛-1｝\cdot \text｛K｝^｛-1｝$ of the pure $\text｛SiO｝_｛2｝$ AR coating. The laser-induced damage threshold (LIDT) of that BN/$\text｛SiO｝_｛2｝$ coating is also 23.1% higher than that of pure $\text｛SiO｝_｛2｝$ AR coating. This research provides a potential application of BN/$\text｛SiO｝_｛2｝$ coatings in high-power laser systems.

A type of $\unicode[STIX]{x1D706}/4$–$\unicode[STIX]{x1D706}/4$ ultra-broadband antireflective coating has been developed using modified low refractive silica and high refractive silica layers by a sol–gel dip coating method for amplifier blast shields of the Shen Guang II high power laser facility (SG-II facility). Deposition of the first layer (high refractive index silica) involves baking at $200\,^{\circ }\text{C}$ in the post-treatment step. The second layer (low refractive index, $n=1.20$) uses low refractive index silica sol modified by acid catalysis. Thermal baking at temperatures no less than $500\,^{\circ }\text{C}$ for 60 min offers chemical stability, ethanol scratch resistance, and resistance to washing with water. The average residual reflection of dual-side-coated fused silica glass was less than 1% in the spectral range from 450 to 950 nm. Transmission gain has been evaluated by taking into account angular light, and the results show that the transmission gain increases with increasing light incidence. Even at $60^{\circ }$, the transmission spectrum of the broadband antireflective coating effectively covered the main absorption peak of Nd:glass.