title: Rayleigh matches and unique green.
abstract: There are recurrent reports that Rayleigh matches are bimodally distributed in the colour-normal male population. Similar claims have been made for the distribution of the spectral locus of unique green. Moreover, a positive correlation has sometimes been reported between Rayleigh matches and unique green. Using a computer-controlled Maxwellian colorimeter and bias-free psychophysical methods, we measured both variables for 97 colour-normal male observers. We do not find a bimodal distribution either of Rayleight matches or of settings of unique green. Nor do we find any correlation between the two variables. However, we do observe a very significant relationship between the lightness of the subject's iris and the wavelength that he judges to be unique green.
authors.affiliation: Department of Experimental Psychology, University of Cambridge, England.
authors.forename: G
authors.initials: G
authors.lastname: Jordan
authors.forename: J D
authors.initials: JD
authors.lastname: Mollon
mesh_terms: D000221:Adaptation, Ocular; D000328:Adult; D003118:Color Perception / Q000502:physiology*; D003119:Color Perception Tests / Q000706:statistics & numerical data; D005127:Eye Color; D006801:Humans; D008297:Male; D011601:Psychophysics; D013053:Spectrophotometry