This paper describes the formation of dielectric interference coatings with refractive index and thickness that are variable in the radial coordinate. Such coatings can be obtained by simultaneously depositing film-forming substances from two evaporators with different rates through a stop located parallel to the plane of the evaporators. The refractive-index distribution of a coating formed by simultaneously evaporating two film-forming substances from sources at different distances from the substrate’s axis of rotation is investigated. Experimental data are presented concerning the refractive index of the films when two oxides are evaporated simultaneously. It is shown that the form factors of these pairs differ: it equals unity in titanium and silicon oxides and zero in hafnium and silicon oxides.
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