Patent ID: 6851806
Filing Date: 2005-02-08
Classification: G02C

Abstract:
1. A progressive multifocal lens for correcting an eyesight, said lens having a progressive refractive surface on an eyeball side, said progressive refractive surface comprising: a far-use portion, a near-use portion having a refractive power different from the far-use portion, and a progressive portion whose refractive power changes progressively between the far-use and near-use portions, wherein the progressive refractive surface is a combination of an original progressive refractive surface for remedying only eyesight and an original toric surface for remedying only astigmia based on a following formula: where z-axis is an axis which passes through a center of the progressive refractive surface from an object side onto the eyeball side, x-axis is in a direction of an cylinder axis of the original toric surface, and y-axis is an axis which is orthogonal to the z-axis and the x-axis, z C C