Class A Color Designation for Light Sources Used in General Illumination

Abstract

Solid state lighting has reignited interest among lighting specialists and manufacturers in the color qualities of illumination used in architectural applications. This renewed interest has highlighted the known problems with the two currently accepted metrics used by the lighting industry to communicate the color qualities of sources of illumination, correlated color temperature (CCT) and color rendering index (CRI). These two metrics are poor predictors of viewer responses to the color characteristics of illumination and both metrics are poorly understood among consumers. The proposed “Class A color” designation serves two important purposes for helping to move the consumer market toward a broader acceptance of solid state lighting. First, the “Class A color” designation reflects bundled metrics shown to be predictive of user acceptance of color attributes from sources of illumination and, second, the designation can be readily understood by consumers as denoting light sources of high color quality.