| 摘要 |
There is provided an intraocular lens, comprising an optic having an anterior surface and a posterior surface disposed about an optical axis, at least one of said surfaces having a profile characterized by superposition of a base profile, the base profile having a base curvature corresponding to a nominal optical power of the lens, and an auxiliary profile, the superposition of the base profile and the auxiliary profile defining a surface comprising an inner refractive region, an outer refractive region and a transition region extending from an outer radial boundary of the inner refractive region to an inner radial boundary of the outer refractive region. The inner refractive region has the base curvature corresponding to the nominal optical power corresponding to a nominal focal plane, the outer refractive region has the base curvature corresponding to the nominal optical power, the transition region (22) is adapted to provide a monotonic change in the optical path difference relative to said outer radial boundary of the inner refractive region (18) as a function of increasing radial distance from the optical axis and wherein the transition region is configured such that an optical phase shift of incident light having a design wavelength across said transition region is defined as: Phase Shift = 2 À » OPD, in which OPD = the optical phase difference, and » designates the design wavelength, which is about 550 nm. So that a first portion of an incoming wavefront in the first refractive region and a second portion of the incoming wavefront in the second refractive region converge in front of or beyond the nominal focal plane. |
