On a recent visit to the eye doctor, at the end of my son’s appointment, the Doc commented to my young son that “someday” he’d be a good candidate for laser surgery to bring his eyes up to 20/20 vision.
On the ride home my son asked me, “If they can correct eyes to 20/20 - can they improve them to better than 20/20?” Good question, but a better question if you’d have asked the Doc 20 minutes ago.
Searching online only show me lots of websites for laser, but I can’t find anything that answers my son’s question: Is it possible to improve human eyes to better than 20/20 vision? If so, why don’t they do it? If not, why not?
Yes. It is really hard to get it that perfect, lots of small flaws can add up. Your fovea nerve density, various small particles trapped in your eye, small flaws in the lens after healing from the corrective surgery, and so on and so forth. The eye charts usually do have a 20/15 line, and it is possible to pass it if everything is just right or you have exceptionally good natural vision.
I’ve heard the people with full lens replacements sometimes hit 20/15.
I’ve also read proposals to make smart glasses with gaze trackers and lidar. Their lenses would deform to perfectly correct your eye to the absolute limits allowed by your fovea, allowing for 20/5 vision in theory. Of course the equipment you’d need wouldn’t come close to fitting in a pair of glasses today, it’s just a proposal.
Accopding to Wiki, yes, it can be better than 20/20, but testers don’t bother to try to exceed that value.
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an eye exam seeks to find the prescription that will provide the best corrected visual performance achievable. The resulting acuity may be greater or less than 6/6 = 1.0. Indeed, a subject diagnosed as having 6/6 vision will often actually have higher visual acuity because, once this standard is attained, the subject is considered to have normal (in the sense of undisturbed) vision and smaller optotypes are not tested. *
TLTE –
Anecdotally, it is said that many athletes had much better vision. Babe Ruth, reputedly, could stand on a newspaper and read the want ads.
Apparently, I once had quite acute corrected vision. I once had a new lens put in to replaced a broken one in my glasses, and when I tried them on, I looked over the salesgirl’s shoulder and she asked what I was looking at. There was a typewritten memo on the wall behind her, at least ten feet away. I told her I was reading that memo, just to check and see if the Rx was accurate. She was surprised that I could read it.
With corrective lenses (such as glasses), sure. My vision is shit without glasses (something equivalent to 20/300-ish), but with them I can read at least the 20/15 line on the Snellen chart. (I didn’t think this was anything unusual.) With laser surgery, I have no idea, though.
I was born with that super vision. I thought the doctors called it 20/18 but it must have been 20/15. I was the only one of 6 siblings not to need glasses. Sigh, that was a long time ago. Still not too bad, I’m 72 and don’t need glasses for ordinary use, although I wear a pair of cheap 1.00 lens while driving to make signs sharper. And 3.25 reading glasses.
I had 20/15 vision when I was 12. Opthamologist told my Mother how good that was. Didn’t last though- at 30 I needed glasses for mild farsightedness and astigmatism, which eventually became extreme in my 60’s.
20/20 is another way of saying ‘normal’ - it means that at 20 feet from the eye chart, you can see what the average person can see when they are 20 feet from the eye chart.
Because that’s based on an average, that means some people already have better than 20/20 - and if their eyes are configured to work better than 20/20, there seems to be no reason why vision couldn’t be corrected to better (just maybe not in all cases though).
If you don’t mind scoping this outside of laser surgery, then improving human vision beyond 20/20 is simple. Use binoculars.
I’ve got a better idea. Let’s just wear our VR headsets around all the time, and put a camera in front that is better than human eyesight. Then we can be enjoying fantasy land most of the time, but when we have to view the real world, it’ll be better than our eyes can do.
Far-sightedness is the inability of your eye lens to focus incoming images on your retina. Not related to VA (visual acuity) which is the ability to discern fine details in a properly focused image. One of them shouldn’t have affected the other.
It seems to me that there are two separate issues, here: The quality of your optics, and the quality of your retina. Glasses and/or contacts can help with the former, but not with the latter. And I think you’d need a better-than-normal retina to get better than 20/20 for both nearby and distant objects.
20/20 has always struck me as odd. I got tested when in my 20’s and given a score better than 20/20. But lots of people do. It could be that the resolution of the the fovea does vary enough between people that this is just the distribution around the mean. It may also be that the original definition of 20/20 was systematically flawed. (Which would not be the first time for such a metric.)
jtur88 is correct; farsightedness is expressed not as a variation from 20/20 distance vision but in some other fashion. (I don’t recall what, but a farsighted person can normally see things clearly at 20 feet, it’s the stuff that’s 3 feet away and closer that gives them fits).
Astimatism, on the other hand, does indeed play havoc with the ability to see things at 20 feet. I have nearsightedness + astigmatism and I’m fully in the “Huh? Top line of the chart, you say? WHAT chart?” category without eyeglasses.