I see, well, honestly I don't use glasses myself...I don't really need them but a quick search on Google landed me on these: click here for the website
I really like these. I am looking into them for myself. I will probably check to see if my eye doctor can put my prescription in the lenses though so I can have them exclusively for biking. I wear contacts or high strength prescription glasses all of the time so wearing actual sunglasses is a luxury, especially when I'm out of contacts.