Sensory System


What does it mean to have 20/20 vision?

Many people think that 20/20 vision equals perfect eyesight, but it actually means that the eye can see clearly at 20 feet (6 meters), which is average for a normal human eye. Some people can see even better, such as 20/15, for example. With 20/15 vision they can view objects from 20 feet (6 meters) away with the same sharpness as a normal-sighted person standing 15 feet (4.5 meters) away.


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