correcting vision better than 20/20

Discussion in 'Eye-Care' started by Bucky, Nov 30, 2006.

  1. Bucky

    Bucky Guest

    Can vision be safely corrected better than 20/20? I'm guessing there
    must be tradeoffs of correcting vision with glasses, contacts, or laser
    beyond 20/20.
    Bucky, Nov 30, 2006
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  2. Bucky

    otisbrown Guest

    Dear Bucky,

    Subject: The "standard" 20/20.

    Most people (no medical condition -- and young), will
    have visual resolution of 1 minute-of-angle, or be
    able to read 3/8 inch letters at 20 feet.

    A number of people can have vision sharper than
    20/20, with the use of a stronger minus lens.

    Some ODs use this as a standard to prescribing
    a minus lens, and this is called prescribing
    for "Best Visual Acuity".

    Most DMV tests require 20/40 with both
    eyes, or 20/40 in the better eye, with no

    Bucky wrote:

    Otis> That is a "loaded" question. It depends on exactly
    what you mean by "safely". Ther are those who
    suggest that a strong minus lens accellerates
    the development of nearsightedness. The
    "jury" is still out on that subject. Some ODs
    call the minus, "poision glasses for children."

    I'm guessing there
    Otis> That is a judgment you will have to make for yourself.


    otisbrown, Dec 1, 2006
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  3. Bucky

    Dan Abel Guest

    20/20 simply means that you see at 20 feet what a "normal" person sees
    at 20 feet.

    The goal in correcting vision is to give you the best possible, not some
    arbitrary number.
    Dan Abel, Dec 1, 2006
  4. Bucky

    Neil Brooks Guest

    This is all very interesting, Otis. WITHOUT pointing to any point of
    your own anatomy, could you kindly cite your source for this

    Neil Brooks, Dec 1, 2006
  5. As Regan once said, "There you go again!".

    In fact, the vast majority of humans can see better than 20/20. Some do
    so with a little plus. Some with a lot of plus. Some with some cyl.
    Some with a zero power rigid contact lens. Some with no lens at all (in
    fact MOST humans in the world fall into this category). And yes, some
    do so with minus lenses. Some with WEAKER minus lenses, some with
    moderate power minus, and yes, a few do so with strong power minus. So
    what? Get over it.

    w.stacy, o.d.
    William Stacy, O.D., Dec 1, 2006
  6. Bucky

    Bucky Guest

    OK, I'm not talking about long term safety. I just mean "safely"
    meaning you can wear that correction all day without getting a
    headache. Can a typical nearsighted person be corrected to 20/5 or
    20/1, or what's the limit?
    Bucky, Dec 1, 2006
  7. Bucky

    Bucky Guest

    So why not attempt to correct nearsighted people's vision to 20/5 or
    20/1? Isn't that better than 20/20?
    Bucky, Dec 1, 2006
  8. Bucky

    otisbrown Guest

    Yes it is, but the AVERAGE of a population was measured
    and established to be about 1 minute-of-arc resolution.

    Or the AVERAGE person could be "corrected" to 20/20,
    or reading 0.9 cm letters at 6 meters.

    Obviously, some can do better, and some can not
    read this size letters.

    In recognition of this fact, the DMV departments had
    set their standard as reading 1.8 cm letters at 6 meters.

    Because some people can not even be "corrected"
    to 20/20.


    otisbrown, Dec 1, 2006
  9. Bucky

    VicTek Guest

    In my experience when the lens was made stronger (beyond optimal) the acuity
    didn't improve. I just experienced discomfort and realized I needed a
    better optometrist.
    VicTek, Dec 1, 2006
  10. Bucky

    odtobe Guest

    To those that may care recent research has determined that if use the
    photoreceptor density in the fovea, part of the eye that gives most
    detailed vision in normal eyes, the estimate for acuity is around 20/8,
    believe it or not. Now that is not the entire story, the light gets
    scattered/reflected/lost a little bit while traveling through the eye
    detracting from this 20/8 possibility.

    I can see 20/15+ with both eyes, corrected with toric soft contact
    lenses, anything less and I go nuts. However, not everyone
    needs/appreciates better acuity, but most are happy with 20/20. The
    reason for the 20/20 can have a lot to due with leading an exam, if
    20/20 acuity or better is met you can rule out a lot of pathology or
    additional problem, if 20/20 is not met investigation as to why is

    Sorry to be long winded.
    odtobe, Dec 1, 2006
  11. Bucky

    Dan Abel Guest

    They better be happy. By definition, 20/20 is "normal" vision.
    Dan Abel, Dec 1, 2006
  12. Bucky

    Bucky Guest

    Ahh, thank you, that was a helpful analogy.

    How about lenses that also magnify then? Let's say a baseball player
    who is 20/20 wants to be 20/10. Could he get lenses that magnify to
    achieve that resolution? In this case, I suppose that the tradeoff
    would be field of view. But is this possible?
    Bucky, Dec 1, 2006
  13. Bucky

    otisbrown Guest

    Dear Bucky,

    Bucky> How about lenses that also magnify then? Let's say a baseball
    Yes, a 4 power telescope will provide that type
    of angular magnification -- but not very practical.


    otisbrown, Dec 2, 2006
  14. Bucky

    A Lieberma Guest

    Dear Bucky,

    Please disregard Otis's postings. He is not in the medical profession and
    not in any position to give medical advice.


    A Lieberma, Dec 2, 2006
  15. Ok otis, now you amaze me. You actually made a statement that makes
    sense. I'm dumbfounded. I don't know what to say. If you are that
    smart, why then do you keep posting the other nonsense stuff on this

    w.stacy, o.d.
    William Stacy, O.D., Dec 2, 2006
  16. Bucky

    otisbrown Guest

    Ok otis, now you amaze me. You actually made a statement that makes
    sense. I'm dumbfounded. I don't know what to say. If you are that
    smart, why then do you keep posting the other nonsense stuff on this

    Otis> Thanks!

    Otis> And as you might know, I do have friends in both ophthamology
    and optometry. But we respect each other. They have been



    w.stacy, o.d.
    otisbrown, Dec 3, 2006
  17. Bucky

    David Combs Guest

    For absolute proof of that, just look at people's
    eyeglasses -- how clean/dirty they are!

    (Likewise, check out their cars' windshields -- same

    David Combs, Dec 22, 2006
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