Abstract

The characteristic of the retinal images projected from two objects lying in the same visual direction is that the order of the retinal images in one eye is reversed with regard to that in the other eye. To examine how the brain solves the correspondence problem when two matches violate ordering constraint, we measured depth of double images in this stimulus configuration. The results show that the perceived distance between two objects is the half of the actual one when two objects differs in size or luminance contrast, implying that the depth of the double image is determined by multiple matching. By contrast, the perceived distance between two stimuli is the same as the actual one when they are different in contrast polarity. These results suggest that the visual system apply the ordering constraints between matches with different size or different contrast, not between those with different polarity.