Sapphire window with double-sided anti-reflection microstructure and preparation method of sapphire window

The sapphire window comprises a sapphire substrate layer and is characterized in that a first microstructure array is prepared on the upper surface of the sapphire substrate layer, a second microstructure array or a first optical thin film is prepared on the lower surface of the sapphire substrate layer, and a second microstructure array or a second optical thin film is prepared on the lower surface of the sapphire substrate layer. The first microstructure array and the second microstructure array are of a one-dimensional grating structure, the depth of a groove ranges from 140 nm to 220 nm, and the transmittance within the wavelength range of 715 nm to 920 nm is 98% or above. According to the method, the transmittance can be improved while the window is resistant to corrosion, high temperature and high in stability. The preparation difficulty and the etching difficulty on the sapphire can be effectively reduced. 本发明提出了一种双面增透微结构的蓝宝石窗口及其制备方法，包括蓝宝石基板层，其特征在于在该蓝宝石基板层上表面制备第一微结构阵列，在该蓝宝石基板层下表面制备第二微结构阵列或者第一光学薄膜，所述第一微