Preparation of hydrophobicshortwaveband antireflective film by SolGel process and its performance analysis

With the development of largescale high power laser system, large size shortwaveband（such as 355nm）antireflective coatings are needed. In this paper, the SolGel deriving SiO2 nanostructure shortwaveband antireflective coatings were prepared. Ellipsometer, FTIR, UVVisVIR spectrometer and AFM were used to characterize the properties of the films. The refractive index of the film is about 1.22, and the thickness is 75nm. The reflectance of the film（on silica substrate）at 355nm is reduced to 0.2％. The scratchresistant property of film was improved obviously after ammonia treatment, the maximum transmission values of the film are only reoluced 0.13% and 0.39% after 20 and 50 times scratch by the tampon with dirty. After surface modification the hydrophobicity of the film is