Panum's Fusional Area.
Illustration of the limited region in space where binocular fusion
(seeing a single image arising from both eyes) is possible. For
illustration purposes, this fusional area is 10 times the size it is in
Binocular Suppression and Rivalry.
Illustration of binocular suppression, where the image from one eye
blocks the perception of the image from the other eye, and binocular
rivalry, where the images from the two eye are alternatively seen.