Abstract: In ultra-precision optical systems, the loss of highly reflective thin films is less and less required. A method to reduce scattering loss by plating one or more thin films to control field intensity is proposed. Firstly, TFCalc optical film analysis software is used to construct three Al high-reflective films, G/Al/A, G/AlLH/A and G/AlLHLH/A (high and low refractive index materials are TiO₂ and SiO₂), respectively, using K9 glass as the base and metal Al, and their reflectivity and field intensity are analyzed respectively. Secondly, the scattering models of interface roughness under completely correlated and completely uncorrelated conditions are established respectively, and the relationship between BRDF and scattering angle of the film surface is first increased and then decreased by simulation analysis of three film systems. The surface scattering of membrane system G/AlLH/A and membrane system G/AlLHLH/A decreased by 42.32% and 48.84%, respectively, compared with that of membrane system G/Al/A under completely uncorrelated conditions. It is shown that the decrease in scattering coincides with the decrease at the electric field interface. Therefore, the scattering can be effectively reduced by interfacial electric field regulation, which provides guidance for the preparation of low loss thin films.