Characterization of dielectric-coated, metal mirrors using surface plasmon spectroscopy

The surface plasmon spectroscopy (SPS) technique is used in the characterization of dielectric-coated metal mirrors. Experiments performed on a MgF(2)-coated aluminum mirror indicate good agreement between SPS and ellipsometry techniques for the determination of coating thickness. In addition, the optical constants of aluminum obtained from the same experiment agree well with values presented in the literature. Advantages of SPS are that it is a simple procedure providing a high degree of accuracy, and only a single measurement is required to yield both the film thickness and the complex permittivity of the substrate.