Band-pass filters


We develop and manufacture optical band-pass filters for a broad range of applications. Band-pass filters are used to transfer energy in a specified, sharply delimited wavelength range and to prevent the transmission of energy outside this range. This is why these filters are specified by quoting the pass band and the blocking band.

Optical band-pass filters usually consist of specially-arranged packs of interference layers which generate high transmission values in the pass band. These dielectric interference filters can be deposited by ion-assisted processes. Ion-beam sputtering (IBS) is used for filters with very strict requirements. This makes it possible to block the blocked areas of the spectrum up to an optical density of OD6.

The filter designs can be combined with absorbing materials or other layer systems and coloured glass products to produce the desired spectral function. Sophisticated filter designs are usually involved in order to satisfy the demanding requirements of their application.

Optical functions

Application examples

  • Band-pass filters for various laser wavelengths in biomedicine
  • Metrology
  • Medical technology
  • Video projectors
  • Events technology


More about applications