Patent ID: 8100527
Filing Date: 2012-01-24
Classification: A61F

Abstract:
1. A multifocal, phakic intraocular lens (IOL) suitable for implantation in an eye while retaining the natural crystalline lens, comprising: an optic providing a far focus and a near focus characterized by an optical power and an add power, the add power being in a range of about 1 D to about 4.5 D, wherein a depth-of-focus associated with at least one of the far or near focus is greater than about 1 D, wherein the optic further comprises an anterior and a posterior optical surface configured to provide the far focus, and a diffractive structure disposed on one of the surfaces providing the add power, wherein the add power of the IOL is selected as a function of a residual accommodation exhibited by the natural crystalline lens, such that a combination of the IOL and the natural crystalline lens provides a visual contrast greater than about 10% at a spatial frequency of about 20 cycles/degree for viewing objects at a distance greater than about 30 cm from the eye, wherein the visual contrast is characterized by a through-focus modulation transfer function (MTF) at a selected radiation wavelength and for a given aperture size, and, wherein the depth-of-focus associated with the far or near focus is selected such that a shift of the far or near focus of the eye caused by the residual accommodation of the natural crystalline lens results in an intermediate or a near vision, respectively, with a visual contrast greater than about 10% at a spatial frequency of about 20 cycles/degree.