Color temperature is measured in Kelvin (K) because it is based on the concept of thermal radiation and the behavior of heated objects. Kelvin is a unit of temperature that is commonly used in scientific and technical fields, particularly in the study of thermodynamics and physics.
Color temperature is a characteristic of light sources, such as light bulbs or the sun, that describes the quality of the light emitted in terms of its perceived color. It is based on the principle that objects at different temperatures emit light with different color appearances.
When an object is heated, it begins to emit light, and the color of the light emitted depends on its temperature. At lower temperatures, the light appears reddish, while at higher temperatures, it becomes bluish. This relationship between temperature and color is known as Planck's law of black-body radiation.
The Kelvin scale is used to measure color temperature because it is an absolute temperature scale that starts from absolute zero (-273.15 degrees Celsius or -459.67 degrees Fahrenheit), the theoretical temperature at which all molecular motion ceases. The Kelvin scale allows for precise measurements and calculations related to temperature, making it suitable for describing color temperatures accurately.
By using Kelvin to measure color temperature, it provides a standardized and objective way to describe the color appearance of light sources, allowing for comparisons and consistent terminology across different lighting technologies and applications.