Purkinje phenomenon
(also Purkinje's phenomenon, phenomenon of Purkinje)
noun
A decrease in the apparent brightness of light of long wavelength (e.g. red) compared with light of short wavelength (e.g. blue) when the degree of illumination falls.
Origin
Late 19th century; earliest use found in American Journal of Psychology. Perhaps after French phénomène de Purkinje; described by Purkinje in Mag. f. die ges. Heilkunde 20 225.