Patent ID: 6964478
Filing Date: 2005-11-15
Classification: G02C

Abstract:
1. Spectacle lens comprising: a region (distance portion) designed for viewing at greater distances and, in particular, “to infinity”; a region (near portion) designed for viewing at short distances and, in particular, “reading distances”; a progression zone disposed between the distance portion and the near portion, in which the power of the spectacle lens increases from the value at the distance reference point located in the distance portion to the value at the near reference point located in the near portion along a line (principal meridian) curving towards the nose; wherein the astigmatic deviation along the principal meridian, i.e. the difference between the prescribed and the actual astigmatism, is less than 0.2 dpt; the maximum astigmatic deviation is less than 1.2 times the addition power (add) which is defined as the difference between the mean “as worn” powers at the distance reference point (D the maximum astigmatic deviation occurs on the nasal side of the principal meridian; and the value of the maximum astigmatic deviation on the nasal side is at most 0.15 dpt greater than the value of the maximum astigmatic deviation on the temporal side wherein the mean “as worn” power D the “as worn” power DN in the region for which y<<(BZ)−7 mm is given by the spacing xA (B   xA ( B F )≧0.06/(add); the spacing xD (B the spacing xA (B the spacing xA (B