US Patent 7717558 Pseudo-accommodative IOL having diffractive zones with varying areas

In one aspect of the invention, a multifocal ophthalmic lens includes an optic and a plurality of diffractive zones disposes about an optical axis of the optic. At least two of the diffractive zones have different areas so as to cause broadening of optical energy profiles at a near focus and a far focus of the diffractive zones for generating an intermediate focus. A fraction of incident optical energy directed to the intermediate focus is different from a fraction of incident optical energy directed to at least one of the near or far foci.