The six thin strips within this circle, created by Professor Akiyoshi Kitaoka, appear to tilt alternately.  In reality, each of the strips are all parallel with one another.  It certainly does not appear that way, but if you hold up a straight edge to the side of each of them, you will see that they are all perfectly straight and parallel.

(via Akiyoshi Kitaoka)

Other Optical Illusions You Might Enjoy

Black Hole Rings by Akiyoshi Kitaoka

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Tick by Akiyoshi Kitaoka

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Illusory Blue Dots by Akiyoshi Kitaoka

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Rotating Chains by Akiyoshi Kitaoka

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Water Cushion by Akiyoshi Kitaoka

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Watermelon by Akiyoshi Kitaoka

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