

Autostereogram -- Wikipedia (hacking binocular vision) - randomwalker
http://en.wikipedia.org/wiki/Autostereogram

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randomwalker
As you go down the page, there are a series of increasingly insightful and
enjoyable examples. I particularly liked the animated random-dot
autostereogram, the one illustrating binocular rivalry (I had no idea there
was a way to experience binocular rivalry without a stereoscope!) and the
chessboard one (where even the pattern is 3D).

Incidentally, I have poor eye accomodation (ability to change focus quickly),
and so once I acquire the stereo perception of a stereogram, I can easily
retain it for 10-15 seconds even if I close my eyes. On the flip side, it's
been 10 minutes since I read that article and I still can't focus my eyes
normally on the screen!

