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Quote:
Originally Posted by jyl View Post
OD -10.50 +2.00 093
OS -11.00 +2.75 092
I was just curious jyl, with a prescription like that, your eye doctor must be a 70 year old Ophthalmologist that still uses ancient vision testing equipment....

Back in the 60's the global optical industry decided to switch to a "minus cylinder" lens design, whereby the cylindrical RX (your astigmatism correction) would be "ground" on the back of the lens, as opposed to a "plus cylinder" design which is ground on the front. This design greatly reduces lens thickness and weight. Plus cylinder lenses and the vision testing equipment that is calibrated to measure plus cylinder correction, if I recall, was pretty much obsolete by the late 60's...not that I've been practicing that long!

So your RX jyl, when transposed (converted) to a minus cylinder format would actually be:

OD: -8.50 / -2.00 X 003
OS: -8.25 / -2.75 X 002

So, in actual fact, you're not as "blind" as you think you are!

Alex
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Old 03-05-2014, 09:45 AM
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