Many Types of 3D Images STEREO PAIR:The great-granddaddy of all 3D images! In 1838 Charles Wheatstone invented the first stereoscopic viewer for the 3D viewing of stereo pairs. Later in the nineteenth century, the viewing of stereo cards became a popular past time. Perhaps your grandparents or great-grandparents had a hand-held stereoscope in their livingroom. To this day, all 3D pictures involve a pair of side-by-side stereo images. Even Magic Eye stereograms have stereo pairs hidden within them. To make things easier at this site, the term "stereo pair" will be used when an actual PAIR of images is visible to the naked eye.
STEREO PHOTOGRAPHS:Stereo photography was very popular in the nineteenth and early twentieth century (hello, Keystone). If you have never viewed a true stereo 3D photograph, you are missing a treat! The detail is amazing and you really feel like you are immersed in the environment you are viewing. A good number of people still take stereo photographs. To find out more visit the site of the National Stereoscopic Association.
STEREOGRAM:Technically, any stereo picture, but in recent years this term has more commonly been used to refer to computer generated Single Image Random Dot Stereograms. A long name, isn't it? That's why Single Image Random Dot Stereograms are also called S.I.R.D.S. At this site, the term "stereogram" is used only to refer to S.I.R.D.S.
RANDOM DOT STEREOGRAM:The prototype for S.I.R.D.S. and Magic Eye stereograms was invented in1959 by Bela Julesz, vision scientist and recipient of the MacArthur Award (a.k.a., the "genius" award). With the random dot stereogram, Dr. Julesz created a computer-generated image that could be perceived only with binocular (two-eyed) depth perception. In one interview the late Dr. Julesz was quoted as saying that he dreamed of inventing a tactile version of the random-dot stereogram, so blind people could experience them. Was this guy cool or what? Of course, random dot stereograms are pretty cool, too.
SINGLE IMAGE RANDOM DOT STEREOGRAM (S.I.R.D.S.):a computer-generated stereogram in which the depth information is combined into a single image (a stereo pair is no longer visible to the naked eye). The first single image random dot stereogram was programmed on an Apple II computer in 1979 by Maureen Clarke and Christopher Tyler.
ANAGLYPH:A stereo image that requires glasses with red and green (or blue) lenses for 3D viewing. The two stereo images are printed on top of each other, but offset. To the naked eye, the image looks overlapping, doubled and blurry. Traditionally, the image for the left eye is printed in red ink and the right eye image is printed in green or blue ink.
LENTICULAR:Most people have seen this type of 3D image in a card shop (perhaps as a postcard of a religious figure). A Lenticular is a thin, portable, full color stereo picture. Thin plastic "lenses" placed over the photograph restrict the view of each eye to a particular part of the picture. Lenticulars can be composed on a computer, but can not viewed on a computer without the aid of expensive specialized attachments. Most of the images on this site involve free-viewing.
Top of Page
Stereo Vision Project
How to See 3D
Magic Eye How to See 3D copyright © 1995; Out-of-Print
by Magic Eye, Inc. and Rachel Cooper, Advocate of Vision Therapy Eye Exercises for Lazy Eye.
All other images and text: copyright © 1996- by Rachel Cooper. All rights reserved.