Patent ID: 7360891

Claim:
A method for designing ophthalmic lenses in which at least one surface among the set of refractive surfaces on the object side and eye side in the mounted state has a spherical or aspherical surface shape that is formed beforehand, and at least one refractive surface has an aspherical surface shape, said method being characterized in that designing is performed so that the shape of the refractive surface whose shape is not formed beforehand among the set of refractive surfaces is an aspherical surface shape which is such that the aberration of the ophthalmic lens is corrected in consideration of the laws of Donders-Listing in accordance with at least the refractive power that is necessary for refractive correction of the user or the refractive power that is necessary for astigmatic correction, or both, said method further being characterized in that an arbitrary meridian of the refractive power necessary for refractive correction of the user is taken as a standard meridian in arbitrary principal rays passing through the plane of the ophthalmic lens, and the shape of the refractive surface whose shape is not formed beforehand is determined so that ΔPall expressed by Equation (1) below shows a minimum value or a specified value or less, where E(α) is the refractive power in the meridian direction that is required for the refractive correction of the eye of the user in the meridian direction at an arbitrary angle of α from the standard meridian, and D(α) is the refractive power in the meridian direction of the lens Δ ⁢ ⁢ Pall = ∫ a b ⁢  Δ ⁢ ⁢ P ⁡ ( α )  ⁢ ⁢ ⅆ α ( 1 ) where, ΔP(α) is a function expressed as ΔP(α)=D(α)−E(α), and a and b are values that satisfy the equation b−a =nπ, where n is a natural number.