The principle of incandescent electric lamps, incandescent lamps are electrical energy into light energy, to provide lighting equipment, the principle of its work is: current through the filament (tungsten wire, melting point of more than 3,000 degrees Celsius) when the heat, continuous heat will be gathered spiral-shaped filament, this causes the filament to reach a temperature of more than 2,000 degrees Celsius. When the filament is in an incandescent state, it gives off light like a red-hot iron. The hotter the filament, the brighter the light it emits. Hence the name Incandescent Light Bulb. In terms of energy conversion, when an incandescent lamp emits light, a great deal of electrical energy is converted into heat, and only a tiny fraction (perhaps less than 1% , uncalculated) can be converted into useful light. Incandescent lamps emit panchromatic light, but the proportion of each color light is determined by the luminous substance (tungsten) and temperature. The imbalance of proportion causes the color deviation of light, so the color of the object under the incandescent lamp is not real enough. The lifetime of an incandescent lamp is related to the temperature of the filament, because the higher the temperature, the more easily the filament will sublimate, these tungsten gas meet the lower temperature of the wall of the lamp and condense on the wall of the lamp and blackened ] , when the tungsten wire sublimated to a relatively thin, after electrifying it is easy to burn off, thus ending the lamp's life. Therefore, the greater the power (wattage) of the incandescent lamp, the shorter its life. What is the principle of electric light? There are two forms of energy release: luminous, EXOTHERMIC, these two forms must coexist. The difference between a filament and a resistive filament is that the filament converts most of its energy into light energy.