Color-Discrimination Index

Abstract

The area of the gamut, in a uniform chromaticity-scale diagram of the chromaticities of a standard array of object colors, is taken to be a measure of color-discrimination capability of an illuminant. The 1960 CIE u, v chromaticity diagram, and the eight test colors of the interim method for computing a color-rendering index, are used for demonstration. Correlation with long-standing subjective evaluations of color rendering of eight commercial lamps is shown. Artificial illuminants excel daylight and the equal-energy spectrum in the gamut of chromaticities of illuminated samples.