Stereopsis with chromatic signals from the blue-sensitive mechanism.
Evidence is presented that the depth seen in dim violet targets superimposed on a bright yellow background is mediated solely by the blue-sensitive mechanism. In forced-choice experiments using these stimuli, observers could discriminate between crossed and uncrossed disparities when the targets were either figural or random dot stereograms. Stereo thresholds for a three bar target whose spatial parameters were adjusted for the B cone mechanism were on the order of 40 sec of arc, a value considerably smaller than the spacing between B cones. With the additional assumption that signals from the blue-sensitive mechanism do not contribute to luminance, these results confirm that purely chromatic signals have access to stereoscopic mechanisms.
D003118:Color Perception / Q000502:physiology*; D003867:Depth Perception / Q000502:physiology*; D006801:Humans; D008027:Light; D010364:Pattern Recognition, Visual / Q000502:physiology; D010786:Photoreceptor Cells / Q000502:physiology; D012684:Sensory Thresholds / Q000502:physiology; D014792:Visual Acuity