uniform chromaticity scale (UCS)

A Uniform Chromaticity Scale (USC) is a two-dimensional color chart in which color changes have the same distance from the perception. The color perception shown refers to colors with the same brightness. Thus, for example, perceived hue decreases are represented in the USC color chart at the same distance from each other. This behavior refers to the entire UCS color diagram.

USC color charts are used in lighting technology for the color evaluation of light sources.