optical filter

Also contains definition of: interference filter
https://doi.org/10.1351/goldbook.O04307
A device which reduces the spectral range (bandpass, cut-off, and interference filter) or @R05046@ of incident radiation (neutral density or @A00514@) upon @T06477@ of radiation.
Source:
PAC, 1996, 68, 2223. (Glossary of terms used in photochemistry (IUPAC Recommendations 1996)) on page 2257 [Terms] [Paper]