Binocular Cue: Retinal Disparity

To better explain retinal disparity, I must define what a binocular cue is first. A binocular cue is a depth cue that depends on the use of two eyes working together to form a picture. Retinal disparity is one cue that falls under the category of a binocular cue. Retinal disparity is the slight difference in the two retinal images due to the angle from which each eye views an object. The picture below helps to explain how this type of cue works. When closing one eye at a time, the picture that one will see is shown on the left hand side. The tree will seem as if it moves some distance to the left or the right, depending on which eye is closed. The picture on the right, however, is the picture of the tree that we would normally see. Both eyes' pictures blend together to create one "whole" for an object. Just for one last clarification, the retinal disparity is the distance that is between those two trees that we see from each eye, or the picture on the left side.

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