The emergence of SSL technology quickly challenged longstanding performance metrics used for assessing color quality, particularly the International Commission on Illumination (CIE) Test Color Method (which includes the General Color Rendering Index R_a, commonly known as CRI). The introduction of new measures of color rendition, especially Illuminating Engineering Society (IES) TM-30-15, has stirred debate within the lighting industry on the relative merits of the tools, as well as the amount of difference between the new tools and prior tools, such as CIE R_a.

As part of its efforts to help industry develop and implement new methods and measures that address CRI’s widely acknowledged limitations, DOE conducts foundational research to augment our understanding of color rendition, and reports on it in peer-reviewed journals. One such article, published online by the journal LEUKOS, is entitled “Comparing Measures of Average Color Fidelity.”