Titanium dioxide (TiO2) has been used in optical coatings for the visible region for many years. TiO has two particularly desirable qualities. It provides the highest index film material for the visible region, and it is hard and stable in combination with other oxides. Coating examples using TiO as the high-index material include beam splitters, cold mirrors and heat-reflecting mirrors, and AR on glass and polymer substrates. Absorption below 450 nm limits the applications to the visible and near-ire regions. When paired with SiO films, multilayer combinations totaling in excess of 50 layers have been deposited that show excellent durability and low mechanical stress because the tensile stress of titania layers is balanced by the compressive stress of the silica layers.Information provided by Materion. |