7/11/2023 0 Comments Candela serratThe Commission Internationale de l'Éclairage (International Commission on Illumination) and the CIPM proposed a "new candle" based on this basic concept. This made it easy for anyone to measure the standard, as high-purity platinum was widely available and easily prepared. The light intensity was due to the Planck radiator (a black body) effect, and was thus independent of the construction of the device. Jules Violle had proposed a standard based on the light emitted by 1 cm 2 of platinum at its melting point (or freezing point), calling this the Violle. It became clear that a better-defined unit was needed. Germany, Austria and Scandinavia used the Hefnerkerze, a unit based on the output of a Hefner lamp. One candlepower was the light produced by a pure spermaceti candle weighing one sixth of a pound and burning at a rate of 120 grains per hour. One of the best-known of these was the English standard of candlepower. These were typically based on the brightness of the flame from a "standard candle" of defined composition, or the brightness of an incandescent filament of specific design. Prior to 1948, various standards for luminous intensity were in use in a number of countries.
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