Luminous flux

Total quantity of light energy emitted per second by a light source

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Luminous flux

Luminous flux is the total quantity of light energy emitted per second by a light source.

It is designated by the symbol F and is expressed in lumens.


Luminous flux measurement of artificial light sources is carried out within a perfectly diffusing white sphere, called an Ulbricht sphere.

This equipment measures the total amount of lumens emitted by the tested light source by comparison with a calibrated lamp.

 Albrecht Sphere measures luminous flux
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