PROGRESSIVE LENS ELEMENTS AND METHODS FOR DESIGNING AND USING SAME

摘要

A series of progressive opthalmatic lens elements, each lens element including a lens surface having an upper viewing zone having a surface power to achieve a refracting power corresponding to distance vision; a lower viewing zone having a greater surface power than the upper viewing zone to achieve a refracting power corresponding to near vision; a corridor of relatively low surface astigmatism connecting the upper and lower zones, said corridor having a surface power varying from that of the upper viewing zone to that of the lower viewing zone; the progressive ophthalmic lens series including a first set of lens elements having a base curve(s) suitable for use in providing a range of distance prescriptions for a first category of patient; and a second set of lens elements having a base curve(s) suitable for use in providing a range of distance prescriptions for a second category of patient; each lens element within a set differing in prescribed addition power and including a progressive design, in at least one of the upper and lower viewing zones, depending upon the addition power of the lens element; the lens elements in the first set differing substantively in progressive design from the corresponding lens elements in the second set due to the differences in base curve(s).