A method for determining the optical constants of an absorbing film entering into the composition of a layered system

A matrix method of calculating the refractive index and the absorption factor of an absorbing film entering into the composition of a multilayer thin-film system (for example, of the dielectric-metal-dielectric type) from the measured transmission and reflection spectra of the system is proposed. The method is based on solution of the matrix equation for the layered system by the iterative method of continuous differential descent. The method developed was applied to determine the optical constants of a real silver film in the composition of a three-layer energetically efficient titanium dioxide-silver-titanium dioxide coating.