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Home > Archive > Lasik Eyes Surgery > July 2006 > Re: This guy had a scary complication in left eye, lost some vision, also poor night v
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Re: This guy had a scary complication in left eye, lost some vision, also poor night v
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| Who cares about the 20/8 estimate, its totally wrong. Like I said, I
have a friend online who is between 20/7 and 20/6 and he has a friend
who is 20/5.
Let me google it.
20/20 is considered normal vision. 20/10 is twice as good. Perfect
vision is about 20/5 which is the limit of resolution of photoreceptors
in the retina and so called diffraction limit for the optical system of
the eye. For all practical purposes 20/10 could be considered perfect.
Our eyes should be able to separate objects that are as close as 0.3
arcminutes apart.
Our eyes have imperfections in the cornea and lens that reduces the
resolution to a practical limit of about 1 arcmin-a factor of about
3.
My comments: This means a 20/15 person may have "perfect" vision devoid
of the tiniest refractive errors or he has mild hyperopia that can be
fully accomodated. Yet his high order aberrations keep him from the
best possible vision of 20/5 or even 20/4 depending on his retina and
optics.
Several other websites show some humans can be capable of 20/5 if you
remove all their aberrations
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