Choose Your Appropriate Lenses
That is, answer this question : Eyeglasses, what for ?
You may need them to correct:
Distance vision only: you need single vision lenses (clear ,or tint or photochromic) with just 1 focal correction for distance vision
Near vision only: requires single vision lenses (clair, or photochromic, or tint) with 1 focal correction for near vision like reading, computer work, or driving
Distance, intermediate, and near vision altogether: you need Progressive lenses -- also known as varifocal or multifocal – (clair, or photochromic ,or tint) appropiately programmed with these 3 corrections. progressive lenses are currently replacing Bifocal lenses given that they have no visible horizontal line in the middle and they deliver a smoother transition between farsightedness and shortsightedness.
Free Form progressive hi-tech lenses provide the same progressive corrections as above (clair or photochromic or tint) but they are individually programmed on their rear surface, near the eye, at the user's specifications and their frame size. Free Form lenses offer the highest vision accuracy.
For further details please referv to “All About Lenses and Frames” page on control bar