Human Body

Nerves and Senses

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) what a normal eye can see clearly at that distance. Some people can see even better—20/15, for example. With their eyes, they can view objects from 20 feet (6 meters) away with the same sharpness that a normal-sighted person would have to move in to 15 feet (4.5 meters) to achieve.


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