title: Contrast matching of two-dimensional compound gratings.
abstract: The contrast of a two-dimensional compound grating consisting of 2, 3 or 4 components with the same spatial frequency but different orientations was matched to the contrast of a simple cosine grating. At all spatial frequencies and contrast levels studied the stimuli which matched in apparent contrast had nearly equal r.m.s. (root-mean-square) but different Michelson contrasts. Thus, matching was based on r.m.s. contrast which takes into account the distribution of luminance levels in the stimulus. A matched filter provides a simple model to explain the contrast matching results.
authors.affiliation: Department of Vision Sciences, University of Aston, Birmingham, England.
authors.forename: K
authors.initials: K
authors.lastname: Tiippana
authors.forename: R
authors.initials: R
authors.lastname: Näsänen
authors.forename: J
authors.initials: J
authors.lastname: Rovamo
mesh_terms: D015350:Contrast Sensitivity / Q000502:physiology*; D006801:Humans; D008433:Mathematics; D008959:Models, Neurological; D010364:Pattern Recognition, Visual / Q000502:physiology*; D012399:Rotation