Patent ID: 9618771
Date: 2017-04-11
CPC Classifications: G02C

Claim:
1. A computer implemented method for manufacturing a progressive ophthalmic lens from a semi-finished lens blank having a regressive front surface exhibiting a final regression and an unfinished rear surface, the manufacturing method comprising the steps of: defining an upper part on each surface of the lens and a lower part on each surface of the lens; choosing a refractive index of the lens; choosing a base value for the front surface of the lens; determining in a determining step a value of regression (d) to be applied to the whole front surface so that said final regression is less than or equal to said value of regression (d), which is the maximum value among first, second and third intermediate values of regression (d=max [d1, d2, d3]), wherein the determining step comprises the sub-steps of: