What does having 20/20 vision mean?!
Question: What does having 20/20 vision mean!?
Ok whats so special about 20/20 vision, why not 17/18 vision or 77/4 vision, like what does it mean, and what would it mean if you had vision in higher or lower numbersWww@Answer-Health@Com
Answers:
20/20 vision means that you see the "20" letter when you are 20 feet away from it!. The "20" letter is a letter that subtends 5 degrees of arc when viewed from 20 feet!.
17/18 would mean that you can see the "18" letter from a distance of 17 feet!. The "18" letter is a letter that subtends 5 degrees of arc when viewed from 18 feet!.
77/4 vision would mean that you can see the "4" letter from a distance of 77 feet!. The "4" letter is a letter that subtends 5 degrees of arc when viewed from 4 feet!.
I think you can see the pattern here!. The top number specifies the distance from the letter chart!. The bottom number specifies the size of letter seen!. By convention, the test distance is 20 ft and the size of letters commonly used are 10, 15, 20, 25, 30, 40, 50, 60, 70, 80, 100, 200 and 400!.
Being able to see a letter that subtends 5 degrees of arc is considered average vision for an eye without disease, so 20/20 is considered average vision!. If you can see a smaller letter
from a further distance, your vision is better than average!. If you can see a larger letter from a closer distance, your vision is worse than average!. So 20/15 is better and 20/40 is worse!.Www@Answer-Health@Com
17/18 would mean that you can see the "18" letter from a distance of 17 feet!. The "18" letter is a letter that subtends 5 degrees of arc when viewed from 18 feet!.
77/4 vision would mean that you can see the "4" letter from a distance of 77 feet!. The "4" letter is a letter that subtends 5 degrees of arc when viewed from 4 feet!.
I think you can see the pattern here!. The top number specifies the distance from the letter chart!. The bottom number specifies the size of letter seen!. By convention, the test distance is 20 ft and the size of letters commonly used are 10, 15, 20, 25, 30, 40, 50, 60, 70, 80, 100, 200 and 400!.
Being able to see a letter that subtends 5 degrees of arc is considered average vision for an eye without disease, so 20/20 is considered average vision!. If you can see a smaller letter
from a further distance, your vision is better than average!. If you can see a larger letter from a closer distance, your vision is worse than average!. So 20/15 is better and 20/40 is worse!.Www@Answer-Health@Com
20/20 means that your vision is clear and that you can distinguish between two objects at 20 feet!. If you have really good vision, it's 20/10; meaning that at 20 feet, you see things that most people can only see at 10 feet!. If your vision isn't as good, maybe it's 20/100-at 20 feet, it looks like something is as blurry as it is 100 feet away for most people!.
It is a silly system in some regards, but they had to come up with something, right!? Just google "visual acuity" and you'll find lots of info!.Www@Answer-Health@Com
It is a silly system in some regards, but they had to come up with something, right!? Just google "visual acuity" and you'll find lots of info!.Www@Answer-Health@Com
it means that a person can see an object or person clearly from a distance of 20 units!.!.!.!. when a person with normal vision can see the same object from a distance of 20 units!. 17/18 would mean, what a normal person can see from 18 units, u need to be 1 unit closer to see it!.!.!.Www@Answer-Health@Com
20/20 is perfect in each eye!. varying numbers would mean varying problems with that particular eye
and as for what the other answerer said, 20 is not the max!. you can be 20 in one eye, 40 in another (or any other number)Www@Answer-Health@Com
and as for what the other answerer said, 20 is not the max!. you can be 20 in one eye, 40 in another (or any other number)Www@Answer-Health@Com
20/20 is the best Vision!.Not a lot of people have it because people tend to watch tv and go on the Computer a lot or find some other way to ruin there eyes(not intentionally though)Www@Answer-Health@Com
the meaning of 20/20 means at you can see 20 feet away and read the 20/20 line Www@Answer-Health@Com
20/20 vision is perfect vision!.!.!.as in there is nothing wrong with ur sight at all!.Www@Answer-Health@Com
perfect vision no need for glasses =]
20 is like a score-the maxWww@Answer-Health@Com
20 is like a score-the maxWww@Answer-Health@Com
perfect sight!. it has something to do with $/$Www@Answer-Health@Com