Title: diffuse reflectance
Long Title: IUPAC Gold Book - diffuse reflectance
DOI: 10.1351/goldbook.08235
Status: current

Definition
Diffuse reflected (remitted) radiant power (\(P_{\rm{rem}}\)) divided by incident radiant power (\(P_{0}\)). \(R = P_{\rm{rem}}/P_{0}\).


Notes
1) The sum of remittance, transmittance, and absorptance equals one.
2) Some authors distinguish between remittance and diffuse reflectance by excluding specular reflection in the latter.

Related Term
- specular reflection: https://goldbook.iupac.org//terms/view/08292

Source
- PAC, 2021, 93, 647. 'Glossary of methods and terms used in analytical spectroscopy (IUPAC Recommendations 2019)' on page 655 (https://doi.org/10.1515/pac-2019-0203)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/08235/html
- json: https://goldbook.iupac.org/terms/view/08235/json
- xml: https://goldbook.iupac.org/terms/view/08235/xml

Citation: Citation: 'diffuse reflectance' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. 10.1351/goldbook.08235
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Disclaimer: The International Union of Pure and Applied Chemistry (IUPAC) is continuously reviewing and, where needed, updating terms in the Compendium of Chemical Terminology (the IUPAC Gold Book). Users of these terms are encouraged to include the version of a term with its use and to check regularly for updates to term definitions that you are using.
Accessed: 2026-06-29T05:19:21+00:00