# why is 20/20 vision considered the standard for good vision? How does the eye differ when people have 20/10 vs 20/200?

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why is 20/20 vision considered the standard for good vision? How does the eye differ when people have 20/10 vs 20/200?

In: Biology

The measurement is a comparison between your vision and the vision of the average person, at the baseline distance of 20 feet.

If you have 20/10 vision, it means that you can see something just as sharp from 20 feet away as a normal person would need to be 10 feet away to see. In other words, 20/10 is substantially above-average eyesight.

Whereas, if your eyesight is 20/200, it means that when you’re 20 feet away from something, you can only see it as well as a normal person can see it from 200 feet away. So 20/200 is really bad eyesight.

Both numbers in 20/20 have meaning. They mean “You can see this from 20 feet away”/”people with normal sight can see this from 20 feet away.” so basically you match up with the expected average

if someone has 20/10 vision, their eyesight is twice as good as the average because everyone else needs to get much closer to see things. If someone have 20/200 vision, that’s the bar for being declared legally blind because you need to practically be right next to something compared to people seeing it clearly from across the room

Is it correct to interpret this as “20/20 vision = average eye sight”?

If so, why wouldn’t lasik make your eyes better than 20/20?