What is binocular overlap?
Most animals have at least some binocular overlap, i.e., a region of space that is viewed by both eyes. This reduces the overall visual field and raises the problem of combining two views of the world, seen from different vantage points, into a coherent whole.
What is stereo overlap?
Binocular overlap refers to the visible overlapping portion between the two eyes of a stereoscopic vision system. In other words, it describes how much of the viewed scene can be seen by both eyes as opposed to by just one of the eyes.