Warped Squares Optical Illusion

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This is an optical illusion where a checkerboard seems to be warped, but by turning the disks or small squares from white to black, you can check that the squares are not deformed.
Contributed by: Enrique Zeleny (February 2014)
Open content licensed under CC BY-NC-SA
Snapshots
Details
Reference
[1] Optical Illusion: Check Your Brain! [Video]. (Dec 17, 2009) www.youtube.com/watch?v=QKCSBkdEUXQ.
Permanent Citation
"Warped Squares Optical Illusion"
http://demonstrations.wolfram.com/WarpedSquaresOpticalIllusion/
Wolfram Demonstrations Project
Published: February 19 2014