Abstract
“Smart Lighting” revolution relies on Light Emitting Diode (LED) lighting sources with unprecedented flexibility, sensing and control. It is now possible to meet individual preferences in lighting and also provide preferred lighting for large groups of people or for specific applications. Alongside with costs and energy savings, smart lighting can greatly improve the perceived quality of light. The key issue is how to take advantage of these enormous opportunities accounting for multichannel LEDs spectral power distributions that are dramatically different from those for more conventional lighting sources. The traditional metrics of light quality are not suitable for LED light sources. To address this issue, we introduced the statistical metrics of color rendering. Now, for the first time, we upgrade the statistical metrics to account for the effects of luminance on human color perception. We report on the revision of the MacAdam ellipses, which are one of the industry de-facto standard for Just Noticeable Difference (JND) perception in color for illuminants by demonstrating and accounting for their dependence on luminance. We will also discuss the application of these results for the trades-off between the LED lighting efficacy and color rendering for different luminance levels (which has implications for energy metrics) and for the implementation of smart lighting systems.