|a screen or mat covered with a dark material for shielding a camera lens from excess light or glare.|
|a children's mummer's parade, as on the Fourth of July, with prizes for the best costumes.|
|lambert (lām'bərt) Pronunciation Key
A unit of luminance in the centimeter-gram-second system, equivalent to the luminance of a perfectly diffusing surface that emits or reflects one lumen per square centimeter. The lambert is named after the Swiss mathematician and physicist Johann Heinrich Lambert (1728-1777).
unit of luminance (brightness) in the centimetre-gram-second system of physical measurement. (See the International System of Units.) It is defined as the brightness of a perfectly diffusing surface that radiates or reflects one lumen per square centimetre. The unit was named for the 18th-century German physicist Johann Heinrich Lambert. It is used by astronomers as well as by physicists, engineers, and photographers.
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