Binocular Cues

Binocular cues are instances where we need to use both of our eyes to determine whether objects are close or far away.  In other words we use both of our eyes to judge depth perception. Too help explain this, think of making a shot in billiards.  You mill most likely be more accurate if you have both of your eyeballs open, allowing you to better perceive how far your ball is from the pocket therefore guaranteeing a more accurate shot.  This is due to the fact that binocular cues are more powerful than monocular cues, or instances where we use one eye to judge depth perception.  One of the major binocular cues is called binocular convergence.  To demonstrate this, take a pool cue and hold it at a reasonable distance from your face, then slowly bring it towards your face.  At some point your eyes will lose focus of the pool cue and strain to see it.  This is because your eye muscles were being strained by trying to rotate beyond their inward limit.

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