Classic geometrical illusion 8
since November 2, 2007
"Shepard illusion with slim and fat girls"
The left girl appears to be slimmer than the right one, though they are identical to each other. This apparent difference depends on the Shepard illusion, one of the most striking geometrical illusions. The Shepard illusion refers to the apparent difference in shape or size between the left and right parallelograms (physically the same shape or size) on that the ladies are drawn.
Copyright Akiyoshi Kitaoka 2008 (April 23)
Shepard illusion or table-top illusion:
Shepard, R. N. (1990) Mind sights: original visual illusions, ambiguities, and other anomalies, with a commentary on the play of mind in perception and art. New York: Freeman.
"Underestimation of the height of a fat person"
The fatter the person is, the smaller he/she appears than he/she is. In contrast, the slimmer the person is, the taller he/she appears than he/she is.
Copyright Akiyoshi Kitaoka 2008 (April 21)
References
"Overestimation of the longer axis of an ellipse"
The slimmer the ellipse is, the longer its longer axis appears than it is.
Copyright Akiyoshi Kitaoka 2007 (December 17)
"Turned-up paper"
The left image appears to be turned up.
Copyright Akiyoshi Kitaoka 2008 (January 14)
"Kaigishitsu no onesan"*
*Ladies in a meeting room
The leftmost, middle and the rightmost ladies appear to be larger than the rest though they are the same in size.
Copyright Akiyoshi Kitaoka 2007 (December 23)
"Ebbinghaus (Titchener) illusion with a lady"
The middle lady in the left group appears to be larger than the one in the right group, though they are the same in size.
Copyright Akiyoshi Kitaoka 2007 (December 23)
"Ponzo illusion and Jastrow's trapezoid illusion with a lady"
The left lady appears to be slightly larger than the right though they are the same in size.
Copyright Akiyoshi Kitaoka 2007 (December 23)
"Ponzo illusion with a lady"
The left lady appears to be slightly larger than the right though they are the same in size.
Copyright Akiyoshi Kitaoka 2007 (December 23)
"Microtubule"
Each inset of the twelve concentric circles appears to be larger (Delboeuf illusion) or thicker than the central circle, though they are physically identical.
Copyright Akiyoshi Kitaoka 2007 (November 3)
Note: A microtubule is a cylinder that has empty space inside and consists of surrounding thirteen tubulins in one cycle. A flagellum has two microtubules at the center and nine mictotubules in the surround. The title of this illusion design came from my confusion between them.
"Nesting Ebbinghaus illusion"
The inset of the left half appears to be larger than that of the right half, though they are the same in size or line thickness.
Copyright Akiyoshi Kitaoka 2007 (November 2)
"Genmitsu tilt illusion"*
*Genmitsu = exactness, strictness
The uppermost two rows appear to tilt clockwise, the next two counterclockwise, and so on. In addition, letter rows appear to move laterally.
Copyright Akiyoshi Kitaoka 2007 (November 2)
Classic geometrical illusion 7
Classic geometrical illusion 6
Classic geometrical illusion 5
Classic geometrical illusion 4
Classic geometrical illusion 3
Classic geometrical illusion 2
Classic geometrical illusion 1