Locate Your Blind Spot |
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Site legend:  = Pop-up window = External window = Adobe .pdf file |      To experience this demonstration, close your left eye and use your right eye to look at the X below. Gradually move closer to or further from the screen (within a range of 4 to 16 inches). At some point you will reach a distance at which the black spot below seems to disappear. At this distance, the spot is falling on your blind spot.  Each eye has a physiologic blind spot. The physiologic blind spot is always present. It is caused by the position of the optic nerve in the rear of the eye. There are no retinal receptors overlying the optic nerve. Fortunately, the physiologic blind spots occur in a different position in each eye. Thus, when both eyes are open, the physiologic blind spots are not apparent. |