radiation

radiation (In French rayonnement) electromagnetic waves characterized by wavelength or their reciprocal frequency, intensity, density, spectral composition and thus also their interactions with the environment. Photometric factors are special cases of radiation field factors:

Q = luminous energy quantité de lumière [lumen × second] = radiant energy énergie rayonnante [joule]

Φ = luminous flux flux lumineux [lumen] = radiant power/flux puissance rayonnante, flux énergétique [watt]

I = luminous intensity intensité lumineuse [candela] = radiant intensity intensité énergétique/de rayonnement [watt per steradian]

E = illuminance, illumination éclairement [lux] = irradiance éclairement énergétique [watt per square meter]

L = luminance, lightness luminance [candela per square meter] = radiance, radiant density radiance, luminance énergétique [watt per steradian × square meter]

H = light exposure, illumination quantity exposition lumineuse, lumination [lux × second] = radiant exposure, irradiation exposition énergétique [joules per square meter]