OPTICAL ELEMENT

摘要

In order to make possible both good laser resistance and good antireflection properties, an optical element (2), in particular for UV lithography, comprising a substrate (20) and a coating on the substrate having at least four layers, is proposed, wherein a first layer (21) comprising a low refractive index inorganic fluoride compound is arranged on the substrate (20), a layer (23) comprising an inorganic oxide-containing compound is arranged as a layer the most distant from the substrate (20), and at least two further layers (222, 223) each comprising an inorganic fluoride compound or an inorganic oxide-containing compound are arranged alternately between the first and the most distant layers (21, 23).