TEILDURCHLAESSIGES OPTISCHES FILTER UND VERFAHREN ZU SEINER HERSTELLUNG.

摘要

A semi-transparent or reflecting optical body and its mfr. are claimed, in which the body has a series of alternately high and low refractive index layers of dielectric materials on a substrate which is transparent at least to long wave radiation. The novelty is that: (a) the total optical thickness (D) of the layer series has a value corresponding to the reference wavelength of the long wave radiation so that the layer series has the properties of an anti-reflection layer for the reference wavelength; and (b) a large number of individual layers are present within the total optical thickness (D) so that the individual optical thickness (S) is small relative to the reference wavelength and has a value corresp. to the reference wavelength of the short wave radiation so that the layer series has the properties of a reflection layer for the short waves.