For chromaticity coordinates in the CIE color system, what does x + y + z equal?

In the CIE color system, chromaticity coordinates are defined in a way that they represent the color information of a light source or object, independent of its intensity. The coordinates are often denoted as (x, y, z). The key aspect of these coordinates is that they are normalized, meaning that when you sum x, y, and z, the total is always equal to 1.

This normalization allows for the representation of colors within a standard gamut and enables colors to be compared or mixed in a consistent manner. Thus, the equation x + y + z = 1 holds true in the context of chromaticity coordinates in the CIE color system. This means that the values of x, y, and z, which correspond to the proportions of three primary colors, must always add up to one.

Every point in the chromaticity diagram corresponds to a particular color and is represented as a point with its coordinates adding up to unity, which supports a simplified representation of color perception and matching in visual contexts.