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Hermann Grid Illusion

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A regular 2-D arrangement of squares separated by vertical and horizontal ``canals.'' Looking at the grid produces the illusion of gray spots in the white Area between square Vertices. The illusion was noted by Hermann (1870) while reading a book on sound by J. Tyndall.


Fineman, M. The Nature of Visual Illusion. New York: Dover, pp. 139-140, 1996.

© 1996-9 Eric W. Weisstein