converting drug-store-cheapie magnification to diopters?

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David Combs - 25 Nov 2008 15:23 GMT

While on long car-trip, at say 7pm on a Saturday night (opticians closed til
Monday), suppose I lose or break my (fortunately both eyes the same!)

(OD +200 sph; OS +200 sph) eyeglasses.

[Actually, this is (I think) for bifocals for which the TOP is
for COMPUTER-BIGSCREEN-DISTANCE and the BOTTOM is for normal reading.]

For an emergency replacement from the nearest drugstore, how to
convert the above prescription, say, into the "stgrength"-measurement
(eg "1.75") printed on drugstore "reading-assist" glasses?

[assume for the above that you end up at Costco or other like
place where you can buy three of the same for $15 -- where all
three come in one of those hard plastic display-containers (where
you end cutting yourself while trying to open it!) -- that is,
you can's just try on various ones to see which works best for you.

ie, it's gotta be by calculation.]

Thanks!

David

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Salmon Egg - 25 Nov 2008 16:07 GMT

> While on long car-trip, at say 7pm on a Saturday night (opticians closed til
> Monday), suppose I lose or break my (fortunately both eyes the same!)
[quoted text clipped - 19 lines]
>
> David

To match the prescription YOUR GIVE ABOVE, use 2.0 reading glasses. This
leaves out any subtleties that may be associated with bifocals. Just try
them out.

I am not a vision professional--it is just a hobby. You don't get advice
worth more than you pay for.

If you are lucky, you might be able to find such glasses at a dollar
store. I still see real cheapies at my 99¢ store and a swap meet.

Bill

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Private Profit; Public Poop! Avoid collateral windfall!

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Dan Abel - 25 Nov 2008 19:55 GMT

> While on long car-trip, at say 7pm on a Saturday night (opticians closed til
> Monday), suppose I lose or break my (fortunately both eyes the same!)
[quoted text clipped - 15 lines]
>
> ie, it's gotta be by calculation.]

Then I guess you're just plain out of luck. Costco (at least mine)
closes at 6PM on the weekends.

:-)

I was going to say that it was really simple, but then I read both
Bill's reply and what you wrote above. I think you are missing the most
important part of your prescription.

Go back to your prescription, and then come back and write down every
number and letter that your doctor wrote down. Perhaps an answer can be
derived from that.

To put it simply, what is marked on reading glasses purchased OTC is the
same as is marked on your prescription. ODs, for some reason, leave out
the decimal point, so the above translates into +2. So, just find
reading glasses marked +2.

A simpler solution would be to go to a drugstore where you can actually
try on the glasses, and find the ones that help you for what you want to
do.

Signature

Dan Abel
Petaluma, California USA
dabel@sonic.net

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David Combs - 26 Nov 2008 13:56 GMT

>> While on long car-trip, at say 7pm on a Saturday night (opticians closed til
>> Monday), suppose I lose or break my (fortunately both eyes the same!)
>>
>> (OD +200 sph; OS +200 sph) eyeglasses.

That is exactly what the optomitrist wrote down.

>> [Actually, this is (I think) for bifocals for which the TOP is
>> for COMPUTER-BIGSCREEN-DISTANCE and the BOTTOM is for normal reading.]
[quoted text clipped - 32 lines]
>try on the glasses, and find the ones that help you for what you want to
>do.

THANKS!

David

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Dr Judy - 26 Nov 2008 14:07 GMT

> While on long car-trip, at say 7pm on a Saturday night (opticians closed til
> Monday), suppose I lose or break my (fortunately both eyes the same!)
[quoted text clipped - 7 lines]
> convert the above prescription, say, into the "stgrength"-measurement
> (eg "1.75") printed on drugstore "reading-assist" glasses?

The number printed on the glasses is the dioptre power, so +2.00 is
2.00. The prescription you posted is not a bifocal prescription
however.

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