Evidently they have changed eye charts since I was a kid. The letters used
to be spaced farther apart and larger. Now they are much smaller, jammed
together and harder to read, especially at the DMV and eye doctor. Probably
these new-fangled computers. Since they've become popular the eye charts
have deteriorated; therefore they must be the cause.
Someone should do something about this! Soon!
You know it's time to clean the refrigerator
when something closes the door from the inside.
I recall a chart that was E's in various orientations.
There are different goals for different types of charts.
Are you trying to *measure* and *characterize* the subjects
vision? E.g., to generate a numerical eyeglass Rx?
Are you checking field of view/peripheral vision?
Are you checking color sensitivity? etc.
I've found most typical approaches to generating a *good*
Rx fail miserably. I attribute this to the fact that we
involuntarily squint -- bringing focusing power to bear -- when
trying to figure out WHAT letter is being displayed.
I had a provider years back who took a very different approach.
Two *large* letters that you examined CASUALLY as he altered
the settings on the phoropter. As you *knew* what the letters
were (they never changed), you didn't "try" to see them clearer.
As a result, you concentrated on "what looks better" instead
of trying to see fine detail.
After coming to satisfactory settings on the phoropter, he'd THEN
put up an eye chart and ask to see how far you could comfortably
read -- to verify the settings!
I've not seen this approach since the early 80's. Eye doctors (optometrists
and opthamologists alike) all seem intent on using a multiline display
(currently a projector using a mirror to "shorten" the size of the
room needed, otherwise) with ever shrinking (and changing!) letters.
Once the "provisional" Rx has been dialed into the phoropter, the
examiner has you review the same chart to see how/if your net vision
[SWMBO went last week -- "new" doctor, same projector approach]
I've not seen the "two large letters" (i.e., 1 foot tall) approach
anywhere but that *one* doctor's office. As a result, I am always
suspicious of the Rx's I've been given in the years, since (which
all seem to suggest my vision hasn't changed in 30+ years! Do I
Define "see". :>
I can sense light vs dark. I can tell round vs. square. I can read
at normal reading distance (haven't developed the "arms too short"
problem). I can spot a pin on the floor from several feet away.
But, I can't read the markings on integrated circuits ("chips")
anymore, without lots of light and magnification. I can't remove a
sliver from my finger without "magnification". I often can't make out
the names on street signs at a distance (but can reason that "the first
letter is round-ish so it's probably OAK street and not ELM"). I
can't recognize faces in passing cars at night (and have to rely on my
knowledge of who drives which types of vehicle, etc.).
I can't legally drive without my glasses. Yet, my Rx is so weak that
folks can mistake it for "clear glass".
So, can I see?
Don't they all do that? I've been wearing glasses for over 60 years so
I've had many exams and every one was done that way. A or B?
When I was a kid they had a big tray of lenses and had to swap them back
and forth by sliding them in and out. I think the alphabet only had 10
letter back then too.
A large (12"?) BLACK 'A' on a green background sitting next to a
large black 'A' on a RED background. "Which is clearer?"
It's called a duochrome test. Your eyes are 8relaxed* while you are
taking it. You're not trying to see the fine detail of a tiny little
'O' (that may actually be a 'C') or 'E' (that may actually be an 'F').
There is no incentive to squinting; you KNOW what the GIANT 'A' is
and it never changes. Squinting doesn't change the RELATIVE clarity
of the red A vs. the green A (i.e., you are seeing two DIFFERENT
images through one eye -- instead of seeing the same image through
two different LENSES!)
What most doctors do is have you focus on some TINY letters and
then play the "which is better; 1 or 2 (2 or 3; 2 or 4; 4 or 5; etc.)"
game -- for each eye.
I can usually read the entire eye chart -- though I can't *see* it!
Instead, I *think* about what each letter likely is -- and I tell
the examiner this ("I can't SEE it but I'm pretty sure it is a 'P',
not an 'F'" "That's fine. What about this next line...?")
On my next exam, I will leave my existing glasses in the car so
the examiner can't check THEIR prescription but has to "work blind"
to come up with my "real" Rx. I'm not sure how I can censor the
"I can't see it" qualifier -- unless I simply refuse to give any
opinion as to what I *think* the letter is!
On Tuesday, March 22, 2016 at 12:10:08 PM UTC-4, KenK wrote:
I often attend meetings in my partner's office and sit in a chair that makes
reading his computer monitor very difficult. The monitor is about 5 feet away.
I also have to be able to read material on the table in front of me and take
notes. I found myself putting my reading glasses on for the closeup work, then
taking them off and squinting to see the monitor. It got really annoying.
I went to the eye doctor and explained the problem. He called his assistant
into the room and had her stand 5 feet away, holding an eye chart. He then
went through the normal "better now, or now" routine with his lens machine
and came up with a bifocal prescription customized for these meetings.
Less trouble and fewer headaches.
I have had the opposite experience.
Used to be I could not even make out the big "E".
Now I am constantly misplacing my glasses because I take them off and am
able to function sometimes for hours without them.
Go figure.... (but it can't be a sign of anything good....)
More importantly, the font they are using now has really fuzzy edges
that make it hard to figure out what the letter is without squinting.
I've also noticed that publishers are using a similar font for books,
which makes it difficult to read the book up close.
Getting older, I know that there can be several different problems with
Besides the need for bifocals, I have incipient AMD and early cataracts.
Surprisingly with glasses I have 20/20 vision and prescription has not
changed in over 5 years but right eye has some central vision haze due
to AMD making it tougher to read books.
Eye doctor also gave me a prescription for computer glasses where top
lens is focused for a couple of feet and bottom for maybe a foot.
Eye doctor recommends taking fish oil and eye vitamins with lutein. My
AMD has not gotten worse in the past 5 years and may just stay the same.
There is nothing you can do about it but you have to keep tabs on it
like looking at an Amsler grid as if it crosses over to wet AMD you can
do things to fix it.
Might also mention that Americans are being hosed for price of glasses.
I get mine at Zenni Optical for about 10% of what suppliers here sell
for. My wife had cataract surgery where Medicare pays 40% for price of
new glasses but it still cost her $500. She won't buy from Zenni and
send her money to China but I tell her I spend savings for American beer.
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