3D cross-eye stereogram

A stereogram is an optical illusion of depth created from flat, two-dimensional images. Originally, stereogram referred to a pair of stereo images which could be viewed using stereoscope.

Stereogram was discovered by Charles Wheatstone in 1838. He found an explanation of binocular vision which led him to construct a stereoscope based on a combination of prisms and mirrors to allow a person to see 3D images from two 2D pictures.

Here are some really impressive photos I’ve found on the net and there are hundreds of them. These images do not need stereoscopes to view and can be viewed by slightly defocusing your eyes and then cross them until an image appears in the middle and then relax your eyes to get a stable 3-D image. It’s worth the trouble.

Click on pictures for larger view

And finally a video stereogram,