US Patent 10420638 Multifocal ophthalmic lens having chromatic aberration correction

An ophthalmic lens includes an optic comprising an anterior surface, a posterior surface, and an optical axis. At least one of the anterior surface and the posterior surface has a surface profile including a base curvature, a refractive region having the base curvature, and a diffractive region comprising a diffractive profile including a plurality of diffractive steps. At least a portion of the diffractive profile constitutes a combination of a base diffractive profile defining multiple foci for the ophthalmic lens and an achromatizing structure that reduces longitudinal chromatic aberrations.