This is a first, and a real boon for those that are considering bifocals, trifocals or progressives.

First let me tell you that my parents have tried the bifocals, trifocals and the progressives and none of them seem to stick. They make the user nauseous in many cases the more the different focal lengths come into play.

With true focals, just flicking a slider mechanism will bring nearby or faraway objects into focus.