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
Formula symbol: Φe
Units: W
How to cite the article; suggest additional literature
Author: Dr. Rüdiger Paschotta
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 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.
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See also: radiant energy, optical power, radiant intensity, optical intensity, irradiance, radiometry
and other articles in the categories general optics, light detection and characterization, optical metrology
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2020-05-23
I would like to find the power per unit area reached.
Answer from the author:
Look for irradiance or optical intensity. (Radiant intensity is something different.)