Preparation of a contamination-resistant ultraviolet broadband double-layer antireflective coating

A double-layer broadband antireflection (AR) coating with excellent transmittance at 250–400 nm has been designed and prepared by the sol-gel method. The quarter-half double-layer structure is optimized by FilmStar film design software. The top layer is the mesoporous SiO 2 film prepared from an ethane-epoxy-propane-epoxy-triblock copolymer as a template, and the bottom layer is the ZrO 2 -SiO 2 hybrid coating with a matching refractive index. The refractive indices and film thicknesses of the top layer and bottom layer of the measured AR coating were determined as 1.282, 57.9 nm and 1.636, 93.2 nm, respectively. The obtained double-layer AR coating can achieve an average transmittance of 99.34% in the wavelength range of 250–400 nm. The surface modification of the AR coating uses 1H, 1H, 2H, 2H-perfluorodecyltriethoxysilane, which greatly improves the pollution resistance of the coating. This study provides a way for the preparation of UV AR coatings with good optical performance and environmental stability and has potential applications in optical detectors.