User:Tharring/sandbox

Thomas L. Harrington, contemporaneously and independently from Tyler, discovered the phenomenon of "self-stereopsis" where stereoscopic depth information is woven into a single pattern rather than into a pair of disparate patterns, one for the left eye and the other for the right.

The patterns of Tyler and others were produced by "shingling." Rows of visual shingles, "vanes," of various shapes were drawn on the display such that, when the viewer's eyes were crossed or diverged appropriately, adjacent shingles overlapped and were seen in illusory depth. The resulting surface of shingles obscured the presumptive ground behind them. The impression of shingled depth is emphatic but, as Tyler noted, the shingled, discontinuous appearance is an inherent limitation of shingled self-stereoptic displays over standard standard stereo pairs.

Harrington employed a shingle free procedure using iterative equations for producing horizontal self stereoptic rows of arbitrarily small widely spaced pattern points. Instead of seeing individual textural objects, shingles, at various depths with a surface presumed by the brain to lie under them, the surfaces in Harrington's patterns are seen as surfaces, per se. They are smoothly continuous, emphatically visible and yet totally transparent.

These self-stereoptic patterns have several additional features. Among them is the possibility of simulating layers of multiple surfaces lying at different depths one behind another, even intersecting one another. Thus multiple layered physical surfaces such as geologic strata can be represented. The figural elements of these individual surfaces can be variously colored or otherwise delineated in order to name them or distinguish them from one another, though this is not visually necessary. Inherent in the geometry of the situation is an especially apparitional feature. It is well known that when viewing a self-stereoptic display with eyes appropriately converged or diverged for viewing the simulated 3-dimensional object, if the eyes are converged or diverged even  more the simulated depth is enhanced or diminished. The original surface disappears and a new one emerges from the display. Additional increases of convergence or divergence elicit additional surfaces, each seen individually (unlike the multiple layered surfaces described above). Thus each self-stereoptic display has a manifold of surfaces embedded in it that depend on where the viewer fixates. The tantalizing extension is this: suppose that one first simulates a surface or object self-stereoptically and then makes an actual physical duplicate of the visual simulation with plaster of Paris or some other homogeneous modeling medium. Then appropriate figural elements are added to the plaster such that the physical model and the self-stereoptic object are perceptually identical  when the self-stereoptic display is viewed with the eyes appropriately "verged" and the physical object is viewed normally. Imagine that the viewer is viewing the flat self-stereoptic display and when he/she blinks you deftly place the real object on the flat display exactly where the simulation had appeared to be--the viewer, in theory, would not notice a difference. Next discard the flat self-stereoptic display and in its place view the real object as though it were a flat self-stereoptic display. First, of course, you will see the simulated surface, real this time. Then, with the same successive mis-fixations as used above, the real object will disappear and the same manifold of individual surfaces will be seen as were seen with the self-stereoptic manifold. This manifold will include the original flat pattern.

forms such as lettering lying on the surfaces In the 1970s, Christopher Tyler invented autostereograms, random-dot stereograms that can be viewed without a stereoscope.[9] This led to the popular Magic Eye pictures.

Gian Poggio and others found neurons in V2 of the monkey brain that responded to the depth of random-dot stereograms.[8]

In 1989 Medina demonstrated with photographs

NOTES…………………………………………… seems too detailed for 'stereopsis' maybe just claim the date and put the details elsewhere.

there are some other articles--autostereograms(?). autostereopsis, magic eye? etc. autostereogram (“Magic Eye” “random-dot autostereogram” (also known as single-image random-dot stereogram tyler has an immense vita on wiki wiki article Autostereogram notes follow: An autostereogram is a single-image stereogram (SIS) autostereogram has a very large with examples wallpaper autostereogram. When viewed with proper vergence, the repeating patterns appear to float above or below the background. The Magic Eye books feature another type of autostereogram called a random dot HISTORYautostereogram. Brewster also discovered the "wallpaper effect"

wallpaper-style "autostereograms" (also known as single-image stereograms).[2]

In 1979, Christopher Tyler of Smith-Kettlewell Institute, a student of Julesz and a visual psychophysicist, combined the theories behind single-image wallpaper stereograms and random-dot stereograms to create the first "random-dot autostereogram" (also known as single-image random-dot stereogram). WOULD BE A GOOD PLACE FOR HARRINGTON CONTEMPORANEOUSLY AND INDEPENDENTLY……

TYLER'S APPROACH ET AL START FROM MODULATING THE SINGLE-IMAGE RANDOM-DOT WALLPAPER STEREOGRAM

NEED TO NAME MY PATTERN TECHNIQUE

But Dr. Christopher Tyler, inventor of the autostereogram, consistently refers to single-image stereograms as autostereograms to distinguish them from other forms of stereograms.[7] Is also known as Single Image Random Dot Stereogram (SIRDS). This term also refers to autostereograms where the hidden 3D image is created using a random pattern of dots.[17]

Tyler, C.W. and Clarke, M.B. (1990) "The Autostereogram". Stereoscopic Displays and Applications, Proc. SPIE Vol. 1258:182–196.