Preparation method of depolarization beam-splitting film with environmental stability

Abstract

The invention discloses a preparation method of a depolarization beam-splitting film with environmental stability, and relates to the technical field of optical thin films. The initial structure of the prepared thin film is GM (LMHM) PLA, G is a substrate, M is SiO2, the refractive index is 1.465, L is MgF2, the refractive index is 1.376, H is TiO2, the refractive index is 2.24, P is a period, generally 5-10 periods, A is air, the substrate is K9 glass, a layer of SiO2 thin film is plated on the substrate in advance and is tightly combined with the substrate, a MgF2 sealing film is used on the outermost layer, and the thickness of the SiO2 thin film is smaller than that of the K9 glass. And the attack of corrosive substances in the environment on the film is effectively resisted in the use process. And secondly, a radio frequency ion assisted evaporation coating method is adopted, and the coated product is subjected to annealing treatment for multiple times, so that enough energy and growth time are provided for the growth of the film. According to the depolarization beam-splitting film prepared by the invention, the polarization spectrum separation amount of the transition zone P-and S-at 50% transmittance is relatively small at an incident angle of 45 + / -10 degrees, meanwhile, the environmental stability of the film is improved, and the service life of the film is prolonged.

Images