Lens Materials for Semi-Rimless Frames
I would like to re-lens my RX semi rimless frame. I've browsed a website that offers 1.56 index lens with transion at competitive price and i was just wandering if this type of lens will fit quite well in a semi rimless frame?
Well, the first thing is that in semi-rimless frames the only material possible to shape is the plastic. With the glass, lenses are not feasible because the optician cannot make the correct shape for the thin wire that holds the lens in place.
The polycarbonate lens is hard to shape and impossible to fit for this kind of frame.
The second thing is that the diopters are critical because a very thin lens is also not possible to shape for this sort of lens. There is a minimum thickness the lens must have to shape it the right way.
So I would say that you should ask your optician about the lens index before you order it and show him the frame so he can calculate the thickness of the glass after shaping.
It also matters if you have (-) or (+) diopters and how high the diopters are because they have different thicknesses and act differently in this kind of frame.
Hope this helps,