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lumen
(redirected from lumens)

   Also found in: Dictionary/thesaurus, Medical, Wikipedia, Hutchinson 0.03 sec.
lumen: see photometry photometry (fōtŏm`ətrē)
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lumen

A unit of measurement of the amount of brightness that comes from a light source. Lumens define "luminous flux," which is energy within the range of frequencies we perceive as light. For example, a wax candle generates 13 lumens; a 100 watt bulb generates 1,200 lumens.

Lumen Ratings for Data Projectors
When choosing a data projector, the lumen rating is an important specification. In a darkened room, 500 lumens may be ample; however, in a conference room with normal lighting, 1,000 lumens would be better. In a room with daylight, 2,000 lumens is preferred. The standard lumen rating of a data projector is the average of photometer readings at several points on a full white image on the screen. See ANSI lumen, candela and spectrum.


lumen [′lü·mən]
(anatomy)
The interior space within a tubular structure, such as within a blood vessel, a duct, or the intestine.
(optics)
The unit of luminous flux, equal to the luminous flux emitted within a unit solid angle (1 steradian) from a point source having a uniform intensity of 1 candela, or to the luminous flux received on a unit surface, all points of which are at a unit distance from such a source. Symbolized lm.
(science and technology)
The space within a tube.


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LUGA comes in natural white, with an output of 400 lumens, and warm white, with an output of 280 lumens and an average color rendering index of 84.
If transformers aren't your style, the company has also released the wireless TDP-TW100U, which has 2700 lumens and retails for $1,699.
If transformers aren't your style, Toshiba has also released the wireless TDP-TW100U, which has 2700 lumens and retails for $1,699.
 
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