| CPC G02B 5/281 (2013.01) [G02B 5/207 (2013.01); H04N 23/55 (2023.01)] | 10 Claims |

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1. An interference filter, comprising:
a substrate;
a filter stack comprising alternating layers of optical coatings with different refractive indices arranged on the substrate; and
at least one absorption layer of an optically absorbing material arranged on the substrate, wherein
the layers of optical coatings are characterized by an overall transmission spectrum and an overall reflection spectrum that are arranged to give the interference filter one of a long-pass spectrum having at least one spectral cut-on wavelength, a short-pass spectrum having at least one spectral cut-off wavelength, or a band-pass filter spectrum having at least one spectral cut-on wavelength and at least one spectral cut-off wavelength,
the spectral cut-on wavelength corresponds to a wavelength at which the transmission increases to 50% throughput,
the spectral cut-off wavelength corresponds to a wavelength at which the transmission decreases to 50% throughput, and
at least one absorption peak of an absorption spectrum of the at least one absorption layer matches the spectral cut-off wavelength and/or spectral cut-on wavelength.
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