20/10 vision

MachFly

MachFly

En-Route
Joined
Oct 3, 2011
Messages
2,514
Display Name
Display name:
MachFly
I'm thinking about getting glasses that will give me 20/10 vision in order to increase my situational awareness and traffic spotting. From a medical prospective is there any disadvantage in me wearing such glasses?
Is it possible that my eyes will gets used to glasses and my vision without glasses will deteriorate? I don't plan on wearing them all day long, only when I fly.

Thanks
 
My guess is not an issue. Near sighted people routinely go through life with 20/10 or 20/15 vision with glasses, myself included, and it's never been mentioned as a potential problem and we wear them all the time.

Of course our vision was crap to begin with so....
 
The potential problem, as explained by my optometrist, Dr. Jil Klein, is that overcorrection results in reduced image size, and can make it harder to see small objects far away. This would be counterproductive to spotting traffic in flight. She demonstrated this in her office using various lenses and small objects. If you correct to an honest 20/20, you're at an optimal balance between precision and image size, and you shouldn't try to fix something that isn't broken.
 
Ron Levy said:
The potential problem, as explained by my optometrist, Dr. Jil Klein, is that overcorrection results in reduced image size, and can make it harder to see small objects far away. This would be counterproductive to spotting traffic in flight. She demonstrated this in her office using various lenses and small objects. If you correct to an honest 20/20, you're at an optimal balance between precision and image size, and you shouldn't try to fix something that isn't broken.
Click to expand...

He's right. I had I done and large objects do look smaller.
 
Last edited:
over-correction for myopia....generally does not usually occur unless your doctor is very sloppy and the teeny bit that might be over-corrected won't make a difference in situational awareness. 20/10 isn't going to make the plane twice as big compared to someone who only sees 20/20. Measuring Snellen vision has to do with measuring the difference between 2 points in a static background with a certain amount of illuminance. Obviously you want to see as well as possible but I've got plenty of patients who have spouses that see the same on my eyechart with correction but one says they can read street signs better than the other.

Also, glasses have magnification or minification distortion that is much greater than when one wears contact lenses. A farsighted person that wears glasses gets a bonus, sorta, because their glasses provide a magnification effect. The opposite effect occurs for a nearsighted person.
 
Would a farsighted person wear glasses for anything other than reading?
 
Silvaire said:
Would a farsighted person wear glasses for anything other than reading?
Click to expand...

From experience, yes- once you reach the age where your eyes can no longer "auto correct" your farsightedness.

Jim
 
that's called presbyopia. seems like a lot of people don't know that word but it's what everyone gets in their 40's.

farsightedness is not quite the opposite of nearsightedness because a lot of people can be young, see distance and near perfectly and they're still farsighted. When we're kids we've have a whole lot of focus power and many times there's no need to correct their farsightedness unless there are complaints.

Silvaire said:
Would a farsighted person wear glasses for anything other than reading?
Click to expand...
 
you got it! I was thinking of making it my vanity license plate but maybe only an OD might figure it out.

and btw, presbyopia means old eyes in Greek. Just what my patients want to hear, right :)



Ron Levy said:
BTW, I see that "od" in your ID -- Doctor of Optometry, like my pal Jil Klein, right?
Click to expand...
 
I have 20/15 corrected in my one and only eye. I took a SODA with the FAA a while back and passed with flying colors. I only used those glasses for flying, with no ill effects.

-John
 
Sac. Dude, that was just so uncalled for on this forum.



Sent from my iPad using Tapatalk HD
 
Oh, wow, I totally forgot I posted that. Oh well.
 
I always though that 20/20 is what a normal human sees in 20 feet, is that not true? If it is true then 20/10 should be twice as good.

I guess I can understand how things can appear smaller but as far as I understand it just seems that way because you see more. Just like looking at a high resolution picture on a small computer screen, the quality is good but because there is a lot in the picture you don't notice anything. So on a computer screen when you what to analyze something specific you just zoom in, human eye technically can do the same by focusing on the object.
 
pilotod said:
that's called presbyopia. seems like a lot of people don't know that word but it's what everyone gets in their 40's.

farsightedness is not quite the opposite of nearsightedness because a lot of people can be young, see distance and near perfectly and they're still farsighted. When we're kids we've have a whole lot of focus power and many times there's no need to correct their farsightedness unless there are complaints.
Click to expand...

So then myself, as a near sighted person in his late 50's and wearing bi-focals, now suffers from both conditions? :sad: Well, at least when I'm wearing my glasses. Without my glasses I have perfect vision from about six to ten inches, which comes in handy for threading needles or reading tiny numbers on 24 gauge wires but not much else.
 
Ron Levy said:
If you correct to an honest 20/20, you're at an optimal balance between precision and image size, and you shouldn't try to fix something that isn't broken.
Click to expand...

I don't understand what this is all about. If your vision can be improved to better than 20/20, by eliminating astigmatism for example, that's a great thing, and it does not make the image size any different.

My vision was a lot better than 20/20 after wavefront lasik surgery. Nothing looked small. It just looked sharp. Really sharp.

Six years later, I've regressed to 20/20, due to the development of astigmatism. Nothing looks larger. Just less sharp. Not complaining, but I know for sure after my experience that 20/20 is not the best somebody can hope for.
 
I had lasik surgery over ten years ago and mine was corrected from 20/400 to 20/15. Objects indeed looked smaller initially but my (brain?) quickly adjusted. The same effect happened when I switched from old glasses to new glasses.

I still have 20/15 vision.
 
yes, I can diagnose from a distance. you have both myopia (nearsightedness) and your new (relatively) condition (since you wear bifocals) is presbyopia. But you also can take your glasses off and read just fine....because you're nearsighted. people who are not nearsighted and are 58 can't see clearly up close...ok, there are a fewsome who will argue about that.

Silvaire said:
So then myself, as a near sighted person in his late 50's and wearing bi-focals, now suffers from both conditions? :sad: Well, at least when I'm wearing my glasses. Without my glasses I have perfect vision from about six to ten inches, which comes in handy for threading needles or reading tiny numbers on 24 gauge wires but not much else.
Click to expand...
 
I came across this thread while doing a Google search on 20/10 vision. I am highly interested in the subject and do work in this area. It first came about when I was in the process of correcting a patient's vision with some new lens design. The patient had a bad LASIK result and was only correcting to 20/30 vision with any contact lens. I created a lens with wavefront guided optics and got her vision to 20/10 or better. Since then I have had a number of similar results. From what I am able to determine, the true incidence of 20/10 or better vision in the general population is about 1 in 300.

Vision scientists have determined that the retinal limits of vision are in the 20/8 range, and that the vision of most people is limited by the optics of the eye. It follows that if the optics can be improved, then 20/10 or better vision should be achievable for most people. This is not a matter of over-correction, it is a matter of a more precise correction and creating a coherent wavefront where all the light reaches the intended spot at the same time. Further, it is not believed that this result can be achieved with eyeglasses because of registration error in the optics.

I hope these comments contribute a little more understanding to the subject, and also open the door to further discussion if there is an interest.
 
Last edited:
I am not a medical person but my understanding is that you don't want to be too overcorrected, especially when you get older, or you will have more trouble focusing close. As someone said, I think it has to do with the muscles in your eyes not being as efficient as when you were young.
 
Certainly you are correct. However, as I said in my post, this is not a matter of over-correction. It is a matter of more precise correction. If you over-correct a myope, you're in effect creating an artificial hyperope (farsighted eye). If you over-correct a hyperope, you are creating an artificial myope (nearsighted eye).

This idea of creating custom 20/10 vision with contact lenses has been around for awhile, but researchers sort of gave up on it save a few because of lack of commercial interest from the big boys. It then migrated to the surgical correction arena (LASIK, PRK, etc.), but the results weren't so predictable.

I got interested because I work with so many wonky eyes and if I can find one more line of vision for them they are very grateful.
 
Last edited:
DrG-OD said:
Certainly you are correct. However, as I said in my post, this is not a matter of over-correction. It is a matter of more precise correction. If you over-correct a myope, you're in effect creating an artificial hyperope (farsighted eye). If you over-correct a hyperope, you are creating an artificial myope (nearsighted eye).

This idea of creating custom 20/10 vision with contact lenses has been around for awhile, but researchers sort of gave up on it save a few because of lack of commercial interest from the big boys. It then migrated to the surgical correction arena (LASIK, PRK, etc.), but the results weren't so predictable.

I got interested because I work with so many wonky eyes and if I can find one more line of vision for them they are very grateful.
Click to expand...

In my mind it's one thing to experiment with contacts but surgery is something else.

My eye doctor corrected me in contacts to 20/20 then told me to wear cheaters if I felt I needed them. That was OK for a long time but there are many times I want to wear glasses instead so now I am going to try progressives. I ordered them but haven't gotten them yet.
 
Agreed. However, the use of wavefront optics is beyond the experimental stage. Wavefront LASIK is now routine.

I'm signing off for now as I have to go earn a living. Thanks for the interest and the discussion.
 
DrG-OD said:
Agreed. However, the use of wavefront optics is beyond the experimental stage. Wavefront LASIK is now routine.

I'm signing off for now as I have to go earn a living. Thanks for the interest and the discussion.
Click to expand...

I meant experimenting with 20/10. I know the surgery itself has been around for awhile.
 
DrG-OD said:
Vision scientists have determined that the retinal limits of vision are in the 20/8 range, and that the vision of most people is limited by the optics of the eye. It follows that if the optics can be improved, then 20/10 or better vision should be achievable for most people. This is not a matter of over-correction, it is a matter of a more precise correction and creating a coherent wavefront where all the light reaches the intended spot at the same time. Further, it is not believed that this result can be achieved with eyeglasses because of registration error in the optics.
Click to expand...

Sounds reasonable to me, based on my experience as a LASIK patient.
 
DrG-OD said:
I came across this thread while doing a Google search on 20/10 vision. I am highly interested in the subject and do work in this area. It first came about when I was in the process of correcting a patient's vision with some new lens design. The patient had a bad LASIK result and was only correcting to 20/30 vision with any contact lens. I created a lens with wavefront guided optics and got her vision to 20/10 or better. Since then I have had a number of similar results. From what I am able to determine, the true incidence of 20/10 or better vision in the general population is about 1 in 300.

Vision scientists have determined that the retinal limits of vision are in the 20/8 range, and that the vision of most people is limited by the optics of the eye. It follows that if the optics can be improved, then 20/10 or better vision should be achievable for most people. This is not a matter of over-correction, it is a matter of a more precise correction and creating a coherent wavefront where all the light reaches the intended spot at the same time. Further, it is not believed that this result can be achieved with eyeglasses because of registration error in the optics.

I hope these comments contribute a little more understanding to the subject, and also open the door to further discussion if there is an interest.
Click to expand...

Good to know, thanks.
 
Better off looking outside more. I'd like to see a study of pilots using one of those retina tracking devices to measure how much pilots are really looking outside. My guess is we'd be embarrassed, appalled, and afraid of the results. Not any of us here of course, those other pilots...
 
ClimbnSink said:
Better off looking outside more. I'd like to see a study of pilots using one of those retina tracking devices to measure how much pilots are really looking outside. My guess is we'd be embarrassed, appalled, and afraid of the results. Not any of us here of course, those other pilots...
Click to expand...

Ha, now that's interesting. Of course you might be right and it makes me rethink how pilots really do function in their environments. I've heard it said by another vision consultant that some of combat pilots with the best kill records enjoyed slightly less than 20/20 vision. Perhaps 20/10 would not be that much of an advantage for a pilot, and that is what I am trying to figure out.
 
ClimbnSink said:
Better off looking outside more. I'd like to see a study of pilots using one of those retina tracking devices to measure how much pilots are really looking outside. My guess is we'd be embarrassed, appalled, and afraid of the results. Not any of us here of course, those other pilots...
Click to expand...

I wouldn't mind that at all, I really do think that I spend minimum time inside.
 
DrG-OD said:
Ha, now that's interesting. Of course you might be right and it makes me rethink how pilots really do function in their environments. I've heard it said by another vision consultant that some of combat pilots with the best kill records enjoyed slightly less than 20/20 vision. Perhaps 20/10 would not be that much of an advantage for a pilot, and that is what I am trying to figure out.
Click to expand...

I flown with one guy who had 20/10, he could spot traffic better than a freaken TIS.
 
I'm slightly over corrected due to mistakes made by optometrists (not Docs) when I was young, and how annoyed I get if I get a normal 20/20 pair of glasses.

Since I work a lot at computer screens, it's also a good reminder method to look away frequently at something else, letting the eyeballs do some focusing work. I go back and forth from the monitor to looking outside at stuff fairly far away pretty regularly at the office.

Working from home, I haven't got the windows to do it, so I get up and go outside for a bit every hour or so. Usually during conference calls, when I like to pace around with the cordless phone, anyway.

I'm decent at traffic spotting and even better at reading street signs far enough away to get in the correct lane. Drives the Mrs. nuts. She's corrected to worse than 20/20 due to some other problems she's had that give her a varying amount of astigmatism that never stops changing.
 
I will try to paint a picture.

There are special instruments called aberrometers. Essentially what those do is measure the the path of light that exits the pupil using an array of tiny lenslets. It compares that with the reference beam. The type I have utilizes a low power laser and measures 256 points sequentially in a few hundred milliseconds. From that a power map or wavefront map can be generated for every eye. The power map looks like a potato chip because the optics are imperfect. Essentially the brain fills in for the imperfections. The potato chip moves up and down the power scale depending on whether the eye is nearsighted or farsighted. The perfect eye would have a map that is perfectly flat, and at zero on the power scale. Then one could say that the vision in that eye was no longer optically limited, but limited only by the resolution of the retina and the brain.

Those imperfections are called aberrations. Some of those change from day to day, others over a period of years. Eye surgery alters them dramatically, which is why this technology is so important to the LASIK industry. They are also pupil dependent, so people with smaller pupils tend to have less aberrated vision. If some treatments can make them worse, then why not try to make them better with a contact lens? Anyway, that's what interests me.
 
You must log in or register to reply here.
Back
Top