Computational experiments on the design of antireflection coatings and an empirical expression for the minimum residual reflectance

A simple empirical expression for the minimum residual reflectance of antireflection coatings is proposed. The expression relates the minimum residual reflectance in the antireflection spectral range to the basic design parameters. The numerically and empirically calculated values of residual reflectance are in good agreement. An accurate qualitative analysis of the expression is given.