Antireflection film, optical element, optical system, method of producing antireflection film

Abstract

An antireflection film is formed by laminating an interlayer, a silver-containing metal layer containing silver, and a dielectric layer in this order from the substrate, an anchor region including an oxide of an anchor metal is provided between the silver-containing metal layer and the interlayer, a cap region including an oxide of the anchor metal included in the anchor region is provided between the silver-containing metal layer and the dielectric layer, a crystal grain size obtained by X-ray diffraction measurement in the silver-containing metal layer is less than 6.8 nm, and the anchor metal has a surface energy less than a surface energy of silver and greater than a surface energy of a layer of the interlayer closest to the silver-containing metal layer.

Dependencies are inferred from the claim text.