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color temperature

The color temperature is a means to know the color of the rays emitted by the different light sources.. Credit for laying its foundations goes to an English naturalist named Lord Kelvin. Therefore, the color temperature unit is called the Kelvin degree. These units were built on the basis that if the temperature was raised. black, its color will first turn to standing red, then orange, then yellow, then what is expressed as hot white, and finally its color will tend towards bluish, and the color temperature of the rays is determined based on the temperature of the hot black body when its color is similar to the color of the rays emitted by the source. The black body (which we mentioned) is the one that does not reflect any rays while it is in the cold state, but rather absorbs all the rays falling on it, and it is also required that it be able to resist high temperatures, so this example applies to an iron bar, for example.

On this basis, the units of measurement for color temperature, known by the previous name Kelvin, which is symbolized by the letters (K) and (K), were developed. For example, if the temperature of the body reaches 1000 degrees Celsius, a standing red light will be emitted, and here it is said that the color temperature of this body = 1273 Kelvin. with

And since the color temperature is based only on the relationship between each of the color and the temperature of the black body when it is heated, therefore we find that the color temperature is indicative of the real temperature unless the body is capable of increasing its temperature (such as iron or hot coal, for example). If we mentioned

For example, the temperature of the color of the hot body is 2273 caffeine, which means that its actual temperature = 2000 Celsius, and in that case we mention that the color temperature of this body is a true color temperature. However, the color temperature is often expressed metaphorically, as if we mentioned that the color temperature of the blue sky = 25,000 C, then the color temperature is not a real indication that the actual temperature in the sky = 273 - 25000 24,727 sperm!! In support of the saying that measuring the color temperature is in fact only a figurative expression and has nothing to do with the actual temperature of the hot body, we suppose that we have analyzed the color temperature of the rays coming out of the two-eighth lamp as 3400 K, then we put a yellow optical filter in front of it, it will increase The percentage of yellow rays that pass through the filter, and then we express the color temperature of the rays after placing the filter in a lower unit (such as 2500 K), although its actual temperature has not changed by placing the yellow optical filter or raising it. If we put a blue filter in front of the light source, we express it Color temperature greater than 3400K, such as approximately 6500K, although the light bulb temperature has not changed as a result of the placement or removal of the blue filter. We conclude from the foregoing that the color temperature of the rays coming out from the source. via

A specific photometric is nothing more than a description of the color of the rays it emits only