As we age, we naturally lose the ability to focus clearly between near and far distances. Bifocal and trifocal lenses are the predecessors of varifocal lenses.
Varifocal lenses provide people with presbyopia with clear vision for two or three different ranges, most often for distance, intermediate and near vision.
With a segment in the lower area of the lens, a bifocal or trifocal displays two different or three dioptric powers and meets specific requirements of the wearer.
Varifocals have a soft gradual change in optical power so there is no disconcerting jump from one strength to another, plus the focus is more centre-based.
Varifocal lenses are provided in a wide range of versions.