Buying glasses online - get lens blanks?

I've just talked to a friend of my mother's who is an optometrist (my previous optometrist) but has not been practising for 2 years.


I told her I'd bought glasses online (zenni-optical) but that the glasses didn't seem to be quite the right prescription.


She told me that the most frequent problem with online glasses is that they fit the lenses into the glasses wrongly. She said I should buy "lens blanks" from an online glasses shop (lhuge lenses made to my prescription but not cut/fitted into my frame), then have them fitted into the frame by a local optometrist. This is because the local optometrist gets the measurement of the PD (the distance between your pupils - so do the online stores), but they also measure the distance between the bottom of your frame/lens and your pupil for each eye - which is apparently really important if you have a CYLINDER measurement on your prescription.





HAVE ANY OF YOU BOUGHT LENS BLANKS from an online glasses store? Which stores sell them? Ta!

Buying glasses online - get lens blanks?
I'm not sure how much money that would really save you. Single-vision lens blanks are very cheap; the real cost is the labor of fitting them to the frame. Try Walmart's optical department; for $60 they'll put single vision or basic bifocal lenses into your own frame.
Reply:Why don't you just bring the frame to them and have the lenses made there. It seems like an awful lot of trouble to save a few bucks. This way you'll know they are (hopefully) going to be made right and if there is a problem you actually have someone to help you.
Reply:Almost all online optical vendors mandate having your PUPILLARY DISTANCE, and make your glasses using this measurement. If you ordered from Zenni, you gave them this information and it was used in making your eyeglasses.





If you suspect the PD is faulty, it's easy to check--move the glasses around on your face and try to "center" them to see if the vision is any better than what dead center is now, while on your face. I have done this with my online ordered glasses and I could find no better "sweet spot" than how they sent the glasses to me.





As Footprint mentioned, the vertical measurement is really only important for progressive lenses--or possibly for very, very short lens designs--with a lens that only has a B measurement of 21mm or less, you would have to watch it and be careful of vertical fit. But I have not seen any online vendors offer such short designs (though I have seen them at opticians locally).





As for buying lens blanks--try www.globaleyeglasses.com. They are here in the US, in NYC, and are good about customizing work. They might be able to help you...





P.S. I had Global install some single vision lenses in some Silhouette frames I had, and while the drilling work on the rimless fitting was sloppier than expecxted, the lenses were dead on and fit me, in terms of pupil centration, perfectly. This for $43, as opposes to $259 at my OD's office...
Reply:I doubt very much that any online optical would have any interest in selling you the uncut lenses.





The only time a measurement is taken from bottom of the frame to the pupil is for determining the height to place the reading portion in a progressive bifocal lens.





The center, vertically is always on the geometric centers of the frame...otherwise unwanted prism would be induced when you look down to the bottom portion of the lens.





If you have an astigmatism correction in them, they may be a few degrees off axis.