Term: attenuance filter
https://doi.org/10.1351/goldbook.A00514

Definition:
An optical device (filter) which reduces the radiant power of a light beam by a constant factor over all wavelengths within its operating range. Sometimes called attenuator or neutral density filter.

Related Terms:
1) filter (http://doi.org/10.1351/goldbook.F02384).
2) radiant power (http://doi.org/10.1351/goldbook.R05046).

Source: PAC, 1996, 68, 2223. 'Glossary of terms used in photochemistry (IUPAC Recommendations 1996)' on page 2229 (https://doi.org/10.1351/pac199668122223)

Citation: 'attenuance filter' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.A00514

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