Cafe Wall
The famous Cafe Wall Illusion was discovered by Richard Gregory, on a cafe wall in Bristol, England. It develops when a staggered arrangement of light and dark bricks are separated by thin lines of 'mortar' whose brightness is intermediate between the brightness of the light and dark bricks. This creates a powerful impression of criss-crossing 'slant' in the perfectly horizontal 'mortar' lines.
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Distorted Circle
This is a perfectly round circle,
but the slanting lines appear to distort it.
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Hering's Illusion
The vertical lines are straight and parallel,
but they look as if they are bowed outwards.
The slanting lines simulate perspective
and create a false impression of depth.
Discovered by the physiologist Ewald Hering (1861).
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Probably the most famous and most studied illusion was created by German psychiatrist Franz Müller-Lyer in 1889. Which of the two vertical line segments is longer? Although your visual system tells you that the right one is longer, a ruler would confirm that they are equal in length.
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Zollner's Illusion
The horizontal lines are parallel,
but the slanting lines makes them appear to diverge.
Discovered in 1860 by F. Zöllner. He described it in a letter to
physicist and scholar J. C. Poggendorff, editor of
Annalen der Physik und Chemie, who subsequently discovered the
related Poggendorff illusion.
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About,
Ambiguous,
Optical Art,
Chimera,
Distortion,
Dynamic,
Impossible,
Moire,
Motion,
Unstable.
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