Segmented multifocal ophthalmic lens with undivided central area

摘要

A multifocal refractive lens to focus light on the retina of the eye. The lens is comprised of a plurality of segments, having different optical powers, at least one for distance vision and another for near. The lens does not require orientation to produce adequate far and near vision and normal stereoscopic effect. One or both of the segments having the optical powers may have aspherical lens surface. The central zone of the lens consists of only one lens segment, providing a clear central axis. Segments of the other optical power border the first segment along a path defined by a semi-circle or hyperbola that extends from one point along the periphery of the adjoining segments to another point along the periphery of the adjoining segments.