Where did you get them, and are your glasses rimless? Different materials are used by different retailers, and for different kinds of frames.
Many opticians will use CR39 (index 1.5) because it gives the best quality optics. But it results in thicker lenses that are easily scratched, and they're not unbreakable. Many mass market stores (WalMart, for instance) use polycarbonate (index 1.56 or so) by default. The optics are good enough, but have the added benefit of being tough and almost unbreakable. For certain purposes requiring extra strength (rimless for instance) they'll sell you another high index polymer like Trivex. And, high index (thinnest lenses) is a common upsell, so if you paid for extra-thin lenses, you may have one of these. Index can be anything, but 1.67 and 1.61 are common. If you can provide us some additional information, like which frames, and what your priorities are, then we could make some much more useful suggestions for you. In the meantime, play with the online thickness calculator at http://www.opticampus.com/tools/thickness.php to see if you want to spend the extra money on the thinner lenses. -- Chuck Knight On Wed, Jan 20, 2010 at 2:49 AM, Elle <[email protected]> wrote: > Hi, > > I have some quick questions if anyone is able to answer - > > I don't know what my current lenses are, except that they're plastic > not glass. If I order from Coastal/Clearly Contacts, which lens should > I go with - the free 1.5 lens, the 1.59, or upgrade to the 1.61? > > Here's my prescription - > sph cyl ax > R -3.25 +50 90 > L -3.25 > > I was thinking of going with the 1.59, any thoughts? > > thanks > > > > -- > Check us out at the oft-updated http://glassyeyes.blogspot.com! > > You received this message because you are subscribed to the Google Groups > "GlassyEyes" group. > To post to this group, send email to [email protected] > To unsubscribe from this group, send email to > [email protected] > For more options, visit this group at > http://groups.google.com/group/glassyeyes?hl=en >
-- Check us out at the oft-updated http://glassyeyes.blogspot.com! You received this message because you are subscribed to the Google Groups "GlassyEyes" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/glassyeyes?hl=en
