original question: Which measurement system has the luminous flux units of [Lumen]?
answer: international system of units
answer type: Measurement System.
auxiliary information: The lumen is the SI derived unit of luminous flux, a measure of the total "amount" of visible light emitted by a source. Luminous flux differs from power in that luminous flux measurements reflect the varying sensitivity of the human eye to different wavelengths of light, while radiant flux measurements indicate the total power of all electromagnetic waves emitted, independent of the eye's ability to perceive it. Lumens are related to lux in that one lux is one lumen per square meter. The lumen is defined in relation to the candela as 1 lm = 1 cd‚ãÖsr. A full sphere has a solid angle of 4œÄ steradians, so a light source that uniformly radiates one candela in all directions has a total luminous flux of 1 cd √ó 4œÄ sr = 4œÄ cd‚ãÖsr ‚âà 12.57 lumens.
Can you tell me what measuring system uses luminous flux units of [Lumen]?