公开(公告)号：CA2250615A1

公开(公告)日：1999-04-16

申请号：CA2250615

申请日：1998-10-15

Applicant: ESSILOR INT

Inventor： CHAVEAU JEAN-PIERRE ,  FRANCOIS SANDRINE ,  BOURDONCLE BERNARD

IPC: G02C7/06 ,  A61F2/16 ,  G02C7/02

Abstract: A multifocal ophthalmic lens comprising a far vision region, a near vision region an intermediate vision region and a main meridian of progression passing through these three regions is provided in which a principal length of progression, defined as a ratio between power addition and maximum slope of mean sphere along the meridian is less than 16 mm, sphere varies in a monotonous fashion as a function of angle on a 20 mm radius circle centered on a geometric center of the lens at both sides of said meridian, and in which the far vision region delimited in an upper portion of said lens by lines formed of points for which cylinder is equal to half power addition includes an angular sector having its origin at the geometric center of the lens with an included angle greater than 150.degree.. This provides a good distribution of isocylinder and ionosphere lines over the lens, ensuring progression is very gentle. .theta.