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Area Lighting / Radiation, quantities and units

IEV ref 845-21-043

Symbol
Np

en
photon number
number of photons
quotient of radiant energy and photon energy

N p = Q e hν MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgaruWqVvNCPvMCG4uz 3bqee0evGueE0jxyaibaieYdi9WrpeeC0lXdh9vqqj=hEeea0xXdbb a9frFj0=OqFfea0dXdd9vqaq=JfrVkFHe9pgea0dXdar=Jb9hs0dXd bPYxe9vr0=vr0=vqpWqaaeaaciWacmGadaGadeaaeaGaauaaaOqaaa baaaaaaaaapeGaamOta8aadaWgaaWcbaWdbiaabchaa8aabeaak8qa cqGH9aqpdaWcaaWdaeaapeGaamyua8aadaWgaaWcbaWdbiaabwgaa8 aabeaaaOqaa8qacaWGObGaaGjbVlabe27aUbaaaaa@410D@

where Qe is radiant energy, h is the Planck constant, and ν is the frequency of the corresponding electromagnetic wave

Note 1 to entry: Photon number can also be expressed by the time integral of the photon flux, Φp, over a given duration, Δt:

N p = Δt Φ p dt MathType@MTEF@5@5@+=feaagCart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHXgaruavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGeaGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaqFn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpeWZqaaiqaciWacmGadaGadeaabaGaaqaaaOqaaiaad6eadaWgaaWcbaGaaeiCaaqabaGccqGH9aqpdaWdraqaaiabfA6agnaaBaaaleaacaqGWbaabeaaaeaaimaacqWFuoarcaWG0baabeqdcqGHRiI8aOGaaeizaiaadshaaaa@4138@

Note 2 to entry: The photon number has unit one.

Note 3 to entry: This entry was numbered 845-01-29 in IEC 60050-845:1987.


fr
nombre de photons, m
quotient de l'énergie rayonnante par l'énergie photonique

N p = Q e hν MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgaruWqVvNCPvMCG4uz 3bqee0evGueE0jxyaibaieYdi9WrpeeC0lXdh9vqqj=hEeea0xXdbb a9frFj0=OqFfea0dXdd9vqaq=JfrVkFHe9pgea0dXdar=Jb9hs0dXd bPYxe9vr0=vr0=vqpWqaaeaaciWacmGadaGadeaaeaGaauaaaOqaaa baaaaaaaaapeGaamOta8aadaWgaaWcbaWdbiaabchaa8aabeaak8qa cqGH9aqpdaWcaaWdaeaapeGaamyua8aadaWgaaWcbaWdbiaabwgaa8 aabeaaaOqaa8qacaWGObGaaGjbVlabe27aUbaaaaa@410D@

Qe est l'énergie rayonnante, h est la constante de Planck, et ν est la fréquence de l'onde électromagnétique correspondante

Note 1 à l'article: Le nombre de photons peut également être exprimé par l'intégrale par rapport au temps du flux photonique, Φp, pendant une durée donnée, Δt:

N p = Δt Φ p dt MathType@MTEF@5@5@+=feaagCart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHXgaruavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGeaGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaqFn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpeWZqaaiqaciWacmGadaGadeaabaGaaqaaaOqaaiaad6eadaWgaaWcbaGaaeiCaaqabaGccqGH9aqpdaWdraqaaiabfA6agnaaBaaaleaacaqGWbaabeaaaeaaimaacqWFuoarcaWG0baabeqdcqGHRiI8aOGaaeizaiaadshaaaa@4138@

Note 2 à l'article: L'unité de nombre de photons est un.

Note 3 à l'article: Cet article était numéroté 845-01-29 dans l'IEC 60050-845:1987.


ar
الرقم الفوتونى

de
Photonenanzahl, f

it
numero fotonico
numero di fotoni

ko
광자 수

ja
光子数

pl
liczba fotonów, f

pt
número de fotões

zh
光子数

Publication date: 2020-12
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