Patent ID: 7731357
Filing Date: 2010-06-08
Classification: G02C

Abstract:
1. A method for producing a group of bi-aspherical type progressive-power lenses with each lens having a progressive refractive power action dividedly allotted to a first refractive surface being an object side surface and a second refractive surface being an eyeball side surface, in which lens, when a surface refractive power in a horizontal direction and a surface refractive power in a vertical direction, at a far vision power measurement position F a surface refractive power in a horizontal direction and a surface refractive power in a vertical direction, at a near vision power measurement position N surface astigmatism components at F producing the group of bi-aspherical type progressive-power lenses so that the same first refractive surface is used for at least two or more lenses of different addition powers.