Optical filter that excludes
radiation of
wavenumber greater (wavelength lower) than a certain value and passes
radiation of
wavenumber below (wavelength greater than) this value.
Electrical filter that blocks signal with a modulation frequency above a certain cut-on value and passes signals of frequency below this value.
See also: high-pass filter
Source:
PAC, 2021, 93, 647. 'Glossary of methods and terms used in analytical spectroscopy (IUPAC Recommendations 2019)' on page 666 (https://doi.org/10.1515/pac-2019-0203)