Fourteen university, government, and industrial laboratories prepared a total of twenty pairs of single-layer titanium dioxide films. Several laboratories analyzed the coatings to determine their optical properties, thickness, surface roughness, absorption, wetting contact angle, and crystalline structure. Wide variations were found in the optical and physical properties of the films, even among films produced by nominally the same deposition techniques.

High-reflectivity dense multilayer coatings were produced for the ultraviolet spectral region. Thin-film single layers and UV mirrors were deposited by ion plating and plasma ion-assisted deposition high-energetic technologies. Optical characterizations of HfO2 and SiO2 single layers are made. The optical constants obtained for these two materials are presented. HfO2 and SiO2 mirrors with a reflectance of approximately 99% near 250 nm are reported.

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We present a theoretical and experimental study of a simple layer-by-layer photonic crystal structure designed for the control of the thermal emission in the infrared wavelength domain. We show that a relatively simple structure made of alternated ZnSe homogenous layers and gold microstructured grids can act as a thermal source itself giving us the unique opportunity to tailor its emission spectra. Comparisons between computed and measured transmission and emissivity spectra illustrate the relevance of our approach.

We investigate the origin of low-level scattering from high-quality coatings produced by ion-assisted deposition and ion plating. For this purpose we use the polarization ratio of light scattering to separate surface and bulk effects that characterize the intrinsic action of the thin-film materials. In the first step the method is tested and validated at scattering levels greater than 10(-5). In the second step it is applied at low levels, and the results reveal some anomalies. To conclude, we perform a detailed analysis of scattering resulting from the presence of a few localized defects in the coatings.