Patent ID: 6709103
Filing Date: 2004-03-23
Classification: G02C

Abstract:
A multifocal ophthalmic lens, comprising an optic zone comprising one or more multifocal power zones having a distance vision power and a near vision power and wherein a speed for the optic zone is determined by the following equation:Add(x)=Addpeak*(1/(a*(1+(x/xc)2n))â€ƒâ€ƒ(I) wherein:Add(x) is an instantaneous add power at any point x on a surface of the lens; x is a point on the lens surface at a distance x from the center of the lens; a is a constant; Addpeak is a full peak dioptric add power; xc is a cutoff semi-diameter; n is a variable between 1 and 40; and Add is a value that is equal to the difference in power between the near vision power and distance vision power of the lens.