Color Kinetics Incorporated - 1 -
COLOR TEMPERATURE AND SOLID STATE LIGHTING
Color Temperature is a generally accepted means of describing the color of white light. The term
‘temperature’ refers to a real temperature of a physics concept called a ‘black body’. A black body
absorbs all light and energy that impacts it, but conversely, according to thermodynamics, is also a
perfect emitter. The close equivalent of this can be seen in such materials as iron, which as it is
heated gradually glows hot enough to see in the red, then orange, then yellow up through white
and blue. The temperatures that correspond to those colors are the Color Temperatures.
The temperature scale is a real temperature scale, measured in degrees Kelvin. The Kelvin
temperature scale is the Celsius scale less 273 degrees. Thus, room temperature is about 22C or
300K. The colors then corresponding to particular temperatures are shown in the curve within the
CIE diagram below. The 2000, 3000, 5000 etc are in degrees Kelvin and are shown usually as
2000K, 3000K etc.
Correlated color temperature refers to the closest point on the black body curve to a particular color
as defined by its chromaticity value. This is the x, y value on the CIE Chromaticity chart. The
reference source(s) are color temperatures that fall on the black body curve