Patent ID: 7677725
Filing Date: 2010-03-16
Classification: A61F,G02B,G02C

Abstract:
1. A method of designing an aspheric ophthalmic lens with both refractive and diffractive powers that is capable of reducing chromatic aberration and at least one monochromatic aberration of an eye characterized by combining aspherical refractive and diffractive surfaces, selecting an appropriate eye model, establishing a design lens having at least one aspheric surface with a capacity to reduce monochromatic aberration in said eye model, establishing a diffractive lens element that corrects for chromatic aberration of the model eye; and adjusting the lens surface design in order to obtain a suitably high polychromatic image quality in a form that is weighted to comply with a spectral merit function, wherein said spectral merit function describes a wavelength dependent sensitivity of an eye for selected lighting conditions, wherein the spectral merit function is obtained from a combination of functions and wherein the functions are selected from the group consisting of photopic, scotopic, and mesotopic luminosity functions.