縦格子を通した二次元平面の両眼視によって生じる波状立体面の知覚

Abstract

Subjects observe a horizontal random-dot surface through a transparent board on which stripes of vertical lines are printed. Under this condition, the surface is illusory perceived as a sequence of wave-like three-dimensional surface that does not exist. This phenomenon has not been known so far, and is related to depth perception by stereo-disparity information because the wave-like surface does not appear by monocular viewing. In this paper, we conducted a psychophysical experiment to measure frequencies and locations of those waves. Results of the experiment showed that a frequency of waves increased as an Interval between vertical lines were decreased and as the subject observed the nearer region of the surface. Then we conducted computer simulations based on a computational theory: in that when neighboring two points on the surface are hidden by vertical lines from either left or right retina, they were matched as a congruent point. This algorithm predicted that the stereo matching of those points resulted in a wave-like three-dimension surface. The results of the simulation corresponded to that of the psychophysical experiment with respect to a frequency of waves. It is needed for future investigations to manipulate experimental parameters as widths of vertical lines or density of the random-dot surface, and to onstruct the better computational model explaining how the wave-like surface are constructed by the gross of matched points.