Alcon Inc.
INTRAOCULAR LENSES HAVING ZONE-BY-ZONE STEP HEIGHT CONTROL

Abstract:

A method and system provide an ophthalmic device. The ophthalmic device includes an ophthalmic lens having anterior surface, a posterior surface and at least one diffractive structure including a plurality of zones. The at least one diffractive structure is for at least one of the anterior surface and the posterior surface. Each zone includes at least one echelette having a least one step height. The step height(s) are individually optimized for each zone. To compensate chromatic aberration of eye from distance to a range of vision, a greater than 2.pi. phase step height may be employed and the step height(s) folded by a phase, which is an integer multiple of two multiplied by .pi.. Hence chromatic aberration of eye may be compensated to improve vision from distance to near.