title: Adaptive shift of visual sensitivity balance under ambient illuminant change.
abstract: We examined the relationship between the ambient illuminant chromaticity and changes in the sensitivity balance of the visual system, using illuminants of various chromaticities. The sensitivity of observers was measured in a room with a variable-chromaticity illuminant. The observer's state of chromatic adaptation was measured with unique-white settings. Our results showed that the change in visual sensitivity has a nonlinear correlation with the change in illuminant chromaticity; chromatic adaptation was nearly complete for desaturated illuminants, but the degree of chromatic adaptation became worse as the illuminant became more saturated. We defined a new index, relative cone weights, which represents this relationship well. To measure the role of chromatic induction from the immediate-surround area of the matching stimulus, we performed additional experiments by presenting the test inside a colored or black immediate surround. The results showed that the unique-white settings were not disturbed by the change in immediate-surround color. Our results imply that the room illuminant chromaticity was the primary factor in changing the observer's state of chromatic adaptation.
authors.affiliation: Imaging Science and Engineering Laboratory, Tokyo Institute of Technology, Yokohama, Japan. ikuriki@n.cc.titech.ac.jp
authors.forename: I
authors.initials: I
authors.lastname: Kuriki
authors.forename: K
authors.initials: K
authors.lastname: Uchikawa
mesh_terms: D000222:Adaptation, Physiological / Q000502:physiology; D003118:Color Perception / Q000502:physiology*; D006801:Humans; D008029:Lighting; D010775:Photic Stimulation / Q000379:methods