Measuring the Depth Perception Invoked by a Simple, Sustained, Polarity-Reversed Stereogram

Abstract

The same-sign hypothesis suggests that only those edges in the two retinal images whose luminance gradients have the same sign can be stereoscopically fused to generate a perception of depth. If true, one would expect that the magnitude of the depth induced by a polarity-reversed stereogram (i.e. one where the corresponding figures in the two stereo half images have opposite luminance polarity) should be determined by the disparity of the samesign edges. Here we present a simple, sustained, polarity-reversed stereogram which we believe to be the first example of a polarity-reversed stereogram where this prediction is shown to be true. We conclude by discussing possible reasons why this prediction fails for other polarity-reversed stereograms.