luminous intensity

noun Optics.
the luminous flux in lumens emitted per unit solid angle by a light source, measured in candles.
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Collins
World English Dictionary
luminous intensity
 
n
Iv a measure of the amount of light that a point source radiates in a given direction. It is expressed by the luminous flux leaving the source in that direction per unit of solid angle

Collins English Dictionary - Complete & Unabridged 10th Edition
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American Heritage
Science Dictionary
luminous intensity  
The luminous flux per unit solid angle (per steradian), as measured in a given direction relative to a light source. Its unit is the candela. See also luminance.
The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
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Encyclopedia Britannica
Encyclopedia

luminous intensity

the quantity of visible light that is emitted in unit time per unit solid angle. The unit for the quantity of light flowing from a source in any one second (the luminous power, or luminous flux) is called the lumen. The lumen is evaluated with reference to visual sensation. The sensitivity of the human eye is greatest for light having a wavelength of 555 nanometres (10-9 metre); at this wavelength there are 685 lumens per watt of radiant power, or radiant flux (the luminous efficiency), whereas at other wavelengths the luminous efficiency is less. The unit of luminous intensity is one lumen per steradian, which is the unit of solid angle-there are 4pi steradians about a point enclosed by a spherical surface. This unit of luminous intensity is also called the standard candle, or candela, one lumen per steradian.

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Encyclopedia Britannica, 2008. Encyclopedia Britannica Online.
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Example sentences
Schematic of a setup for using an absolutely calibrated photometer to perform luminous intensity and illuminance measurements.
The luminous intensity shall be controlled automatically by a photocell utilizing pulse width modulation.
The effect of position lamps can be increased by optimizing their color, luminous intensity and distance from the headlamp.
Our additional tests of color quality, luminous intensity, luminance and glare showed similar degrees of variation.
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