Meta-Standards for Color Rendering Metrics and Implications for Sample Spectral Sets

摘要

There is compelling, largely agreed-upon evidence that thernCIE Color Rendering Index (CRI) is not a sufficiently accuraternmeasure of the average color rendering difference between tworndifferent spectral irradiance distributions. This has becomernparticularly evident with the consideration of white light sourcesrnemploying several narrow band light emitters. In this presentationrnan approach is suggested for reducing the error, based onrnconsideration of certain meta-standards for evaluation of proposedrnCRI calculation methods. Here we focus mainly on one such metastandardrn–the idea that the spectral sensitivity of the CRI should bernreasonably uniform and largely independent of the details of thernselected sample set. A key problem with the current CRIrncalculation method, and some suggested improvements, has beenrntheir lack of this important characteristic. By employing thisrnguiding principle, we have devised an improved sample set thatrnsubstantially eliminates the problem of non-uniform spectralrnsensitivity.