Correlation of various light source quality indices with the colour discrimination capacity

The quality of a light source can be measured against various criteria – colour rendering, durability, etc. Another criterion is the quality of the colour of the objects it illuminates. Traditionally, this aspect has been associated almost exclusively with that of colour rendering, but the emergence of new light‐emitting diode technology light sources has led to its being re‐examined. In particular, questions have been raised as to whether colour quality can be calculated by a single measure. Instead, it seems a multidimensional index might better cover such concepts as colour rendering, colour discrimination, harmony, etc. The present work describes a visual colour discrimination experiment whose results corroborate the existence of a multidimensional index, even although some of the parameters commonly used to describe the quality of a light source might be correlated with each other.