Accession Number : ADA268398


Title :   The Effects of Luminance Boundaries on Color Perception


Descriptive Note : Final rept. 15 Mar 1989-14 Jan 1993


Corporate Author : HARVARD UNIV CAMBRIDGE MA DIV OF APPLIED SCIENCES


Personal Author(s) : Kronauer, Richard E ; Stromeyer, III, Charles F ; Chaparro, Alex


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a268398.pdf


Report Date : 20 Jul 1993


Pagination or Media Count : 40


Abstract : The luminance and red-green chromatic detection mechanisms respond to, respectively, the sum and difference of the long-wave (L) and middle-wave (M) cone contrast signals. The most-detectable stimulus is not a small patch of luminance drifting grating, as suggested by others, but rather a small, foveal red-green chromatic flash. Even at the smallest test size examined, 2.3' diameter, the red-green mechanism is more sensitive than the luminance mechanism, which has profound implication for visual physiology. When a suprathreshold luminance flash (a pedestal) occurs coincidentally with a red- green chromatic flash, detection of color is facilitated approx. 2-fold, regardless of spot size, as shown by forced-choice results, and this constant facilitation contrasts with the much larger facilitation reported earlier for small flashes. The lack of chromatic masking by suprathreshold luminance pedestals supports the view of separable luminance and red-green detectors.


Descriptors :   *VISUAL PERCEPTION , *LUMINANCE , *COLOR VISION , TEST AND EVALUATION , CONTRAST , DETECTION , RED(COLOR) , MOTION , FLASHES , PERIPHERAL VISION , MASKING , GREEN(COLOR) , THRESHOLDS(PHYSIOLOGY) , GRATINGS(SPECTRA) , SIGNALS , COLORS , RETINA


Subject Categories : Anatomy and Physiology
      Optics


Distribution Statement : APPROVED FOR PUBLIC RELEASE