That looks like somebody looking at you crosseyed.
Now, look back at him crosseyed. Cross your eyes far enough that you fuse the image from the right eye with the image from the left eye.
Now, you see three Cyclops, that trio of one-eyed gods of ancient times. The one in the middle is seen stereoscopically: His eye is in front, and his pupil is now seen to actually be a retina, located far in the back of his head.
Study of stereopsis, and discovery of stereopsis blindness, was the major work of one-time radar engineer, Bela Julesz of Bell Telephone Laboratories (now Lucent Technologies). His study of seeing through snow on radar screens led to his development of the random-dot stereogram as a research tool. He named his field of study, "Cyclopean perception" because it deals with brain activity in the visual cortex, located in the back of the brain where information from the two eyes is combined and processed. Julesz called this "the cyclopean retina."
Stereopsis is a fascinating phenomenon to study, to play with, to develop into extensions of our perception. It's also a valuable exemplar for helping us understand and form useful models for other human information processing skills.
Do you know where...?
In 1972, I worked out techniques of using random and quasi-random dot patterns in the arts. That year, I gave several seminars around the Northwest on this topic (at Mt Angel College, Portland Art Museum, Evergreen State College, and Portland State University, for example). For those seminars, I made a largely dittoed booklet of stereoscopic patterns and explanations of how to use random-dot patterns in a variety of ways. It was titled, "Cyclopean Art." The first page had at its top the Cyclops stereogram that's at the top of this page. Does anyone know where any copies of that booklet are located today?
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