Metal interference filter
A metal interference filter is a filter that works based on interference . See also anti-reflective coating and interference filter .
Such a filter essentially consists of several thin layers of glass, between which the incident light is reflected, so that a path difference occurs. Due to this path difference, the phases of the electromagnetic wave are shifted from one another, which leads to destructive interference. This extinguishes the light for certain wavelengths. The metal interference filter differs from "normal" interference filters in that one side is vaporized with a thin, semi-permeable metal layer so that the filter can also be exposed to high light intensities or a larger part of the light is reflected several times.
Metal interference filters are used with the pre-mirrored side facing the light, as the other side is dark and there is otherwise the risk that the filter will be too warm and thus damaged.
Individual evidence
- ↑ Internship manuscript HU Berlin: Interference filter (PDF file; 118 kB). gpr.physik.hu-berlin.de, April 22, 2010.