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Radiant Flux

Definition: radiant energy per unit time which is emitted, transmitted, reflected or received by an object

Alternative terms: radiant power, optical power

German: Strahlungsleistung

Categories: general optics, light detection and characterization, optical metrology

Units: W

Formula symbol: <$\Phi_\textrm{e}$>


Cite the article using its DOI: https://doi.org/10.61835/rkw

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The radiant flux is a term of radiometry. It is defined as the radiant energy per unit time which is emitted, transmitted, reflected or received by an object. In the case of light, it is also simply called the optical power. However, the term radiant flux can be used for any kinds of electromagnetic radiation, including e.g. X-rays, ultraviolet light, infrared light and terahertz radiation.

A related quantity is the spectral flux, defined as the radiant flux per unit frequency or wavelength interval. The units are then W/Hz or W/nm, for example.

See also: radiant energy, optical power, radiant intensity, optical intensity, irradiance, radiometry

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I would like to find the power per unit area reached.

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Look for irradiance or optical intensity. (Radiant intensity is something different.)

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