A method of calculating an optical system of an ophthalmic lens according to a given spectacle frame comprising the steps of: • providing geometrical data of the spectacle frame, • providing wearer data, • optimization of the optical system according to criteria consisting of the geometrical data of the spectacle frame, the wearer data and at least one positioning data, so as to generate an optical surface, wherein the at least one positioning data comprises at least the 3D or 2D position of the front face of the ophthalmic lens according to the contour of a front face of the spectacle frame, characterized in that said optimization generates at least two optical surfaces (S1, S2) comprising a front face of the ophthalmic lens and a rear face of the ophthalmic lens, and in that during the optimization step: - edging and beveling parameters are generated which include at least the 2D or 3D position and shape of a bevel on an external profile of the ophthalmic lens, the edging and beveling parameters and the rear face of the ophthalmic lens being calculated according to the geometry of the front face of the ophthalmic lens, and - the ophthalmic lens is calculated so as to position the front face of the ophthalmic lens at a given distance from the front face of the spectacle frame, wherein the optimization criteria further comprise the average distance d between Pf and Pl, Pf being the junction point between the front face of the spectacle frame and the internal profile of the spectacle frame and Pl being the junction point between the front face of the ophthalmic lens and the external profile of the ophthalmic lens, and wherein the positioning data of the ophthalmic lens is calculated so as to have said distance d smaller than 1 mm. • providing geometrical data of the spectacle frame, • providing wearer data, • optimization of the optical system according to criteria consisting of the geometrical data of the spectacle frame, the wearer data and at least one positioning data, so as to generate an optical surface, wherein the at least one positioning data comprises at least the 3D or 2D position of the front face of the ophthalmic lens according to the contour of a front face of the spectacle frame, characterized in that said optimization generates at least two optical surfaces (S1, S2) comprising a front face of the ophthalmic lens and a rear face of the ophthalmic lens, and in that during the optimization step: - edging and beveling parameters are generated which include at least the 2D or 3D position and shape of a bevel on an external profile of the ophthalmic lens, the edging and beveling parameters and the rear face of the ophthalmic lens being calculated according to the geometry of the front face of the ophthalmic lens, and - the ophthalmic lens is calculated so as to position the front face of the ophthalmic lens at a given distance from the front face of the spectacle frame, wherein the optimization criteria further comprise the average distance d between Pf and Pl, Pf being the junction point between the front face of the spectacle frame and the internal profile of the spectacle frame and Pl being the junction point between the front face of the ophthalmic lens and the external profile of the ophthalmic lens, and wherein the positioning data of the ophthalmic lens is calculated so as to have said distance d smaller than 1 mm. - edging and beveling parameters are generated which include at least the 2D or 3D position and shape of a bevel on an external profile of the ophthalmic lens, the edging and beveling parameters and the rear face of the ophthalmic lens being calculated according to the geometry of the front face of the ophthalmic lens, and - the ophthalmic lens is calculated so as to position the front face of the ophthalmic lens at a given distance from the front face of the spectacle frame, wherein the optimization criteria further comprise the average distance d between Pf and Pl, Pf being the junction point between the front face of the spectacle frame and the internal profile of the spectacle frame and Pl being the junction point between the front face of the ophthalmic lens and the external profile of the ophthalmic lens, and wherein the positioning data of the ophthalmic lens is calculated so as to have said distance d smaller than 1 mm.