SiO2纳米微球表面结构在可见光波段的减反特性

研究了不同尺寸SiO2胶体微球形成纳米结构薄膜的光学传输特性和光子带隙。通过在玻璃基底上自组装透光的SiO2胶体微球形成胶体晶体薄膜, 依据布拉格定律，分析微球尺寸对胶体晶体光子带隙的影响。为实现可见光波段的全方位减反射，提出通过改变胶体粒径将胶体晶体带隙位置移动至紫外波段，理论计算得出当粒径为112 nm，占空比为0.45时能实现可见光波段0.5%的平均反射率。实验结果表明，玻璃基底在400~800 nm间的平均反射率从4.3%降低至0.7%，最小反射率达0.3%。通过控制微球粒径移动光子带隙位置，优化晶体结构参数实现了可见光波段的减反射，有效提高了光学组件对可见光的利用率。

Antireflection of Silica Nano-Microsphere Surface Structure in Visible Light

The optical transmission characteristics and the photonic band gap (PBG) of the nano-film are studied which consists of silica colloidal microspheres with different sizes. Nano-colloid crystal film is self-assembled with light transmitted colloidal SiO2 microspheres on glass substrate. Bragg law is used to analyze the influence of the microspheres size on photonic band gap. In order to achieve omni-directional antireflection in the range of visible light, it is proposed to move the bandgap of colloidal crystals to the ultraviolet (UV) band by changing the size of colloidal particle. It is found that close to 0.5% average reflection can be achieved when the particle size is 112 nm, and duty ratio is 0.45. Experimental results show that the average reflectance of glass surfaces is reduced from 4.3% down to 0.7% in the wavelength range from 400 nm to 800 nm. Through controlling colloidal particle size to move the photonic bandgap position, optimizing crystal structure parameters, the antireflection in visible light band is achieved, and the utilization of visible light by the optical components is effectively improved.