Re: Issues with my new high-index lenses...

Thank you, Mark, for this information..and Ann for your input re. the
polished edges. When I ordered the glasses, the salesperson held some
kind of machine up to my eyes and asked me to focus on a central point
in it. He took some readings from this, but there was no fitting done
with regards to the actual frame and definitely no marks made on the
frame's sample lenses. Does the machine's measurements provide the
equivalent of this? It would seem to me that it could not...

This afternoon, I took my glasses to the optician from whom I'd
purchased my previous pair (the Hoya 1.6's) to get his opinion. He
said that the power of the new lenses is correct but the one thing that
struck him was the difference in curve between the old and new lenses.
He suggested that if I ask them to redo the new lenses, fitting them to
the curve of the old ones, he thinks I should see better. I do not
quite understand what he meant... how do opticians determine which
curve of lens to use?

He also said, Ann, as was true in your experience, that they would have
to remake the lenses in order to resolve the polished edge issue...

Thanks again, so much for helping me sort this thing out. You guys are
amazingly generous with your time and expertise!




Before your lenses are made, the optician must first "fit" the frame on your
face in a position that is relatively close to your eyes so that you can
achieve the best vision when the lens is mounted. Then they must mark the
fitting height (just below the horizontal center line of your pupils) and
the pupil distance (pd) which is the width of your pupils. The optician then
makes marks on the sample lens that comes with the frame where these two
points cross on each eye, which is where the optical center point of the
lens must be mounted in your frame.

The lens (which is usually about 75mm round) is then cut to fit the outline
of your frame so the optical center point of the lens is in the correct
position on the frame (as previously determined). I have left out a few
details, but hopefully you get the idea of what a proper fitting entails. In
order for you to have optimal, the fitting must be done properly, and done
accurately. It is not unusual for the fitting to be quite far off, and a
remake is sometimes required.

If you cannot find out from your optician what lens and AR your received, I
would take them to another optician and ask if they know.

Polished edges on a minus power lens can cause internal reflections and be
bothersome, depending on edge thickness and the type of frame.

.

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