Whiteness metric for light sources of arbitrary color temperatures: proposal and application to light-emitting-diodes

We study the quantification of whiteness perception under illumination from various light sources. We discuss an existing metric for sources with high correlated color temperature (CCT), CIE whiteness, and propose a procedure to adapt it to sources of any CCT. We illustrate our approach by comparing the ability of different warm-white sources to render whiteness. We show that a careful engineering of the spectrum -facilitated by the flexibility of light-emitting diode sources - is essential to render whiteness.