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Me? or the archaic eye charts?

I've had three pairs of glasses made up, and returned, over the past two months.  The same MD has done all three exams.  I have no complicating medical problems, and nothing bizarre about my vision.  So, I have no glasses, and the MD, who was already frustrated by visit 2, "just doesn't know," and also repeats his mantra that "you shouldn't expect perfect vision," no matter how many times I assure him I don't expect to.  I do, however, expect to be able to read road signs from a reasonable distance.

So, the eye chart sits there.  It does not move.  It is highlighted in a darkened room.  "What's the lowest line you can read?"  "Focus on the big "E."  None of this is real life, and, besides, they never seem to care if you can only read part of a line, or if you tell them that a letter like "B" is completely illegible to you.  What's the mystery?

The MD firmly, and impatiently, believes that the prescriptions he has written must be accurate.  How can they be, if I have to be almost on top of a large road sign in order to read it?  These charts have been used since the 1860s.  Life is not as slow as it was in the 1860s, and measuring vision within 20 feet - and I'm sure it is far less than 20 feet in this MD's office, isn't rational, is it?

Shouldn't testing equipment match the myriad lights that we're exposed to, the speed of road travel?  How hard would it be?  I paid my money, but don't need to be made to feel like a pain in the neck, and I don't know any office where other than the Snellen chart has been abandoned in favor of more realistic testing, so what to do?
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7765252 tn?1395096028
SD, I imagine the difference in my case may be because I have monofocal IOLs after cataract surgery.  My guess is I don't have the accommodation I used to have.  I should have pointed that out.  Sorry.
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Avatar universal
Correction: "suggests a   prescription enough each time " should of course have been "suggests a   change in prescription large enough each time " to warrant a new pair of glasses.

The result Nancy_in_GA mentions is unusual and doesn't match what should be expected, perhaps someone else has an idea what caused that since I can't think of  anything offhand that would account for that large a difference in a prescription between optical infinity and 20 feet.
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Avatar universal
The fact that you had multiple pairs of glasses made (rather than each prescription matching the others exactly, or close enough not to bother) suggests a   prescription enough each time to warrant making a new pair of glasses. Its unusual for that to happen, and suggests the possibility of another eye health issue that the doctor should be looking for. If the prescription didn't really vary much (vision can vary through the day slightly, and due to various factors like how dry your eye is and fatigue) its possible he gave you a new prescription anyway just in case.   It is  possible if there is an error each time that it is with the place that made the glasses, rather than the doctor.

In addition to the change in prescription, the difficulty seeing road signs suggests there may be other eye issues at play preventing your vision from being as sharp as it could be, unless there really is an error on the part of the doctor or whoever made the glasses.

Since there seems to be an issue with the results from this doctor I'd suggest getting a refraction done someplace else to compare, and preferably trying a different place to have the glasses made (or having another shop test the prescription on the glasses to be sure they match what was requested). . Many MDs are surgeons and focus on that rather than basic tasks like refraction (which they often leave to other staff in their office). Some people say optometrists tend to do better refractions since they do it more often.

There is only a slight difference in strength to focus at optical infinity compared to 20 feet.

http://www.tedmontgomery.com/the_eye/acuity.html
"Traditionally, optical infinity has been accepted to be 20 feet or, approximately, 6 meters.  However, at this distance, there is an accommodative demand on the eye of about 1/6 D (one-sixth of a diopter). "

Although in theory its a concern and some notice the difference like that person, it seems unlikely its going to make enough of a difference to lead to much more difficulty reading reading road signs. The measurements I assume   take into account that 0.17 diopter difference between where the chart is and optical infinity. Even if they didn't   it would either not alter the prescription (which is usually  in 0.25D steps) or only alter it 0.25D, which can make a difference, but not a huge one, likely not enough to cause a big problem seeing road signs..
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7765252 tn?1395096028
Although my optometrist insisted that the eye chart at 20 feet is good enough for "infinity," I insisted he determine my prescription looking out the window across the street.  He held the various lenses in front of my eyes.  It made a 0.75 diopters difference versus using the eye chart.  I'm glad I did, because I can now see road signs clearly enough away that they're actually useful.
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