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Incandescence is the emission of electromagnetic radiation (including visible light) from a hot body as a result of its temperature. The term derives from the Latin verb ''incandescere,'' to glow white. Incandescence is a special case of thermal radiation. Incandescence usually refers specifically to visible light, while thermal radiation refers also to infrared or any other electromagnetic radiation. For a detailed discussion of the intensity and spectrum (color) of incandescence, see the article: thermal radiation. ==Observation and use== (詳細はDraper point. The incandescence does not vanish below that temperature, but it is too weak in the visible spectrum to be perceivable. At higher temperatures, the substance becomes brighter and its color changes from red towards white and finally blue. Incandescence is exploited in incandescent light bulbs, in which a filament is heated to a temperature at which a fraction of the radiation falls in the visible spectrum. The majority of the radiation however, is emitted in the infrared part of the spectrum, rendering incandescent lights relatively inefficient as a light source. If the filament could be made hotter, efficiency would increase; however, there are currently no materials able to withstand such temperatures which would be appropriate for use in lamps. More efficient light sources, such as fluorescent lamps and LEDs, do not function by incandescence. Sunlight is the incandescence of the "white hot" surface of the sun. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Incandescence」の詳細全文を読む スポンサード リンク
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