A unit of brightness; the brightness of a perfectly diffusing surface emitting or reflecting a total luminous flux of 1 lumen/sq cm of surface. [J.H. L., German physicist and mathematician, 1728–1777]
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lam·bert 'lam-bərt n the centimeter-gram-second unit of brightness equal to the brightness of a perfectly diffusing surface that radiates or reflects one lumen per square centimeter
Lam·bert 'läm-.bert Johann Heinrich (1728-1777)
German mathematician, physicist, and philosopher. Largely self-educated, Lambert investigated geometry and astronomy, doing so by means of instruments which he himself designed and built. He also made significant contributions to the knowledge of heat and light. In 1760 he demonstrated for the first time how to measure quantitatively the intensity of light. The cgs unit of measurement for light intensity, the lambert, is named in his honor.
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lam·bert (L) (lamґbərt) [J. H. Lambert] a unit of luminance, being the luminous intensity of a perfect diffuser emitting one lumen per square centimeter. The unit generally used is one thousandth of this and is called a millilambert.Medical dictionary. 2011.