LM has various meanings in the NASA category. Discover the full forms, definitions, and usage contexts of LM in NASA.
An empirical measure of the quantity of light. It is based upon the spectral sensitivity of the photosensors in the human eye under high (daytime) light levels. Photometrically it is the luminous flux emitted with a solid angle (1 steradian) by a point source having a uniform luminous intensity of 1 candela. Standard unit of measure for light flux or light energy. Lamp light output is measured in Lumens. It measures the rtotal amount of visible light emitted from any light source. It is SI derived unit of luminous flux. symbol is im.
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