Abstract: Disclosed is a progressive ophthalmic lens including a front surface and a rear surface, each surface having in each point an altitude, a mean sphere value and a cylinder value, the front surface of the lens including: —a far vision zone having a far vision reference point; —a near vision zone having a near vision reference point; —a main meridian, wherein the front surface is regressive and has: —a sphere gradient normalized value of less than 7.50·10?1 mm?1 at any point in a central portion of the lens including a portion of the main meridian (32), the far vision reference point (FV) and the near vision reference point (NV); —a cylinder gradient normalized value of less than 1.45 mm?1 at any point in the central portion of the lens.

Abstract: A method for designing a mould (120) for casting a semi-finished ophthalmic lens blank, wherein the surface of the mould (120) is designed so that the surface of the mould fits a predetermined closed curve, wherein the predetermined closed curve is representative of the geometry of a gasket (160) to be used in association with the mould (10). A method for assembling a mould assembly (100) and a method for casting a semi-finished ophthalmic lens blank, and a computer program product including software code portions for performing steps of these methods are also described.

Abstract: A process for designing an ophthalmic progressive eyeglass comprises providing an initial front surface and an initial back surface. Respective addition values of front and back surfaces of the eyeglass are varied based on said initial front and back surfaces using a surface derivation tool. These surface addition values are selected so that the eyeglass exhibits an eyeglass addition value which matches a wearer's prescription and a value for a design feature which matches a target value. Said target value may be used for customizing the ophthalmic progressive eyeglass. The process does not require point-to-point surface optimization.

Abstract: Method for customizing an initial ophthalmic lens, the initial ophthalmic lens being customized so as to provide a customized ophthalmic lens, the method comprising: a initial ophthalmic lens data providing step (S1) in which initial data representing the initial ophthalmic lens is provided; a constraint data providing step (S2) in which constraint data comprises at least the outline, the minimum thickness at the optical centre and the minimum thickness at the edges of the initial ophthalmic lens; a prism determining step (S3) in which the prism to be applied to the initial ophthalmic lens so as to minimize the difference between the value of the chosen geometrical parameter of the customized ophthalmic lens and a desired value of the chosen geometrical parameter is determined, wherein the angle of the prism is smaller than or equal to 10°; and the customized ophthalmic lens fulfils the same constraint as the initial ophthalmic lens.