Varifocals

Varifocal lenses allow the wearer the closest thing to the natural vision that they had in their youth.  Most designs require some adaptation time to allow the wearer to become acclimatised to the changing strength of the lenses; and some element of compromise may be required, based on the design chosen, they have no dividing  line visible on the lens surface, allowing the wearer a smooth transitions from distance through to the rear vision.