Reducing light scattering of single-layer TiO2 and single-layer SiO2 optical thin films

The interface roughness of optical thin film is responsible for light scattering losses. Light scattering from optical thin films are becoming increasingly important for manufacturing high quality optical film devices. In this paper, the reducing scattering conditions of single layer optical thin films are analyzed by scattering theory. The ranges of the interfacial roughness ratio for reducing light scattering of single layer with high refractive index and low refractive index are given respectively. The optimal values of roughness ratio corresponding to zero backscattering of single layer film are given. The experimental results are in good agreement with theoretical analysis for single-layer TiO2 thin film of optical thickness lambda/2 and single-layer SiO2 thin film of optical thickness lambda/4.