Method for implementing a filter edge or an optical thin-film bandpass filter, optical thin films and optical components therewith

摘要

Proceeding from the need to filter out, in UV installations for therapy or cosmetics, the UV-B and UV-C spectral range on the one hand, the visible and near infrared spectral range on the other hand and thus to obtain at the optical output essentially only UV-A radiation, the filter edge is implemented in the direction of shorter wavelengths, that is to say essentially between the UV-B and the UV-A ranges by means of the absorption edge of a film material. It is recognised here that in the case of such a film material the absorption edge can be shifted to a desired spectral point as a result of the selection of the material composition. In a filter, whose filter edge is implemented in the direction of larger wavelengths by means of interference at thin films and in which the material, whose absorption edge is utilised, is simultaneously utilised as interference-film material, a shift (a, b) of the filter edge in the direction of shorter wavelengths results from the change in the composition of the mentioned material and thus of its absorption edge. IMAGE