Patent ID: 7108373

Claim:
A method of manufacturing a single vision bi-aspherical spectacle lens, comprising: preparing as semi-finished lenses, axially symmetrical aspherical lenses in which a concave surface has a plurality of predetermined common base curves and are expressed by the following equation (1): Z1 = c · r 2 / ( 1 + 1 - ( 1 + k ) · c 2 · r 2 ) + ∑ n ⁢ a ⁡ ( n ) · r n ( 1 ) wherein the term of the c·r 2 /(1+√{square root over (1−(1+k)·c 2 ·r 2 )} is a rotary secondary curved surface, c denotes a center of the curvature, k denotes a conical coefficient, r denotes a distance between a lens position projected on a horizontal surface of a cylindrical coordinate system and an original point a (n) denotes the coefficient of r n , and ∑ n ⁢ a ⁡ ( n ) · r n denotes a deviation from the rotary secondary curved surface, selecting one of the prepared semi-finished lenses according to a prescription; and designing a concave surface as an aspherical surface expressed by the following equation (2) to satisfy the prescription: Z2 = c ⁡ ( θ ) · r 2 / ( 1 + 1 - ( 1 + k ⁡ ( θ ) ) · c ⁡ ( θ ) 2 · r 2 ) + ∑ n ⁢ a ⁡ ( n , θ ) · r n ( 2 ) where: c(θ), k(θ) are functions for an azimuth θ; a(n, θ) is a coefficient of r n , and a function of the azimuth θ; as for a definition domain of the azimuth θ, 0 degrees to 90 degrees represents 0 degrees to 360 degrees due to plane symmetry of an astigmatic lens; c(θ) is a curvature of a lens center and is expressed by the following equation (3) based on Euler's theorem, letting a curvature of a spectacle principal meridian in a Gaussian curve theorem be c(0) at 0 degrees and c(90) at 90 degrees, wherein 0 degrees is a spherical diopter axis and 90 degrees is an astigmatic diopter axis: c (θ)= c (0)·cos 2 θ+c (90)·sin 2 θ (3); k(θ), is similar to said c(θ), and is expressed by an equation similar to said equation (3) in which the c is replaced by k; and a(n, θ) satisfies requirements of plane continuity and plane symmetry, is a surface capable of controlling an aberration due to an angle deviation which occurs due to Listing's Law, and further satisfies conditions (i) to (iv), as follows: (i): having a functional relation of the azimuth θ from 0 degrees to 90 degrees; (ii): a linear differential coefficient of the azimuth θ is 0 at 0 degrees and 90 degrees; (iii): a high degree differential coefficient is continuous; and (iv): having a control parameter group Ps(n) which is capable of controlling a function, with the azimuth θ set between 0 degrees and 90 degrees (where s is 1, 3 or a number there-between and n refers to a high order function in said equation (2)).