Principles and Nomenclature for the Quantification of Light

  • Lars Olof Björn


This chapter does not deal with any practical aspects of light measurement, only with theoretical concepts. The following concepts are explained: energy fluence, energy fluence rate, photon fluence, photon fluence rate and radiance, mol, as well as the following superfluous or obsolete terms and synonyms: actinic flux, space irradiance, scalar irradiance, spherical irradiance, vectorial irradiance, and einstein. The chapter furthermore deals with spectral weighting of radiation and some psychophysical concepts, such as illuminance, lumen, lux, etc.


Fluence Rate Energy Fluence Unit Cross Sectional Area Photon Fluence Rate Photon Irradiance 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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  1. Björn, L.O. (1995) Estimation of fluence rate from irradiance measurements with a cosine corrected sensor. J. Photochem. Photobiol. B. Biol. 29, 179–183.CrossRefGoogle Scholar
  2. Björn, L.O. and Vogelmann, T.C. (1996) Quantifying light and ultraviolet radiation in plant biology. Photochem. Photobiol. 64, 403–406.Google Scholar
  3. Braslavsky, S.E. et al. (2007) Glossary of terms used in photochemistry. 3rd ed. (International Union of Pure and Applied Chemistry recommendations 2006). Pure Appl. Chem. 79, 293–465. Available at or Scholar
  4. Grum, F. and Becherer, R.J. (1979) Optical radiation measurements. Academic Press, New York, pp. 14–15.Google Scholar
  5. Handbook of Chemistry and Physics (many editions). CRC Press, Cleveland, OH.Google Scholar
  6. Rupert, C.S. (1974). Dosimetric concepts in photobiology. Photochem. Photobiol. 20, 203–212.Google Scholar

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© Springer Science+Business Media, LLC 2008

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  • Lars Olof Björn

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