摘要:
A method for generating a trimming setpoint for an ophthalmic lens to be fitted in a surround of a spectacle frame, includes: a) within a coordinate system of the surround identified by a horizontal axis, acquiring the shape of a longitudinal profile of the surround and the perimeter length of this longitudinal profile; b) within an optical coordinate system of the ophthalmic lens which is identified by a centering point and by a horizontal axis and which is made to coincide with the coordinate system of the surround, centering and orienting the longitudinal profile, c) projecting the acquired longitudinal profile onto a curved surface deduced from a curvature parameter of the ophthalmic lens or from the spectacle frame, d) correcting in two operations, the shape of the projected longitudinal profile, so as to equalize its perimeter length with the perimeter length of the acquired longitudinal profile, and e) deducing from the corrected longitudinal profile the trimming setpoint.
摘要:
A method of calculating a shaping setpoint for an ophthalmic lens along a longitudinal profile includes: an operation of acquiring an initial longitudinal profile; an operation of centering the initial longitudinal profile on the lens; an operation of searching for two remarkable points of the initial longitudinal profile as a function of determined criteria; an operation of calculating a modified axial coordinate for each remarkable point in order to ensure proper mounting and esthetic appearance of the lens in its eyeglass frame; and an operation of calculating a final longitudinal profile resulting from a transformation of the initial longitudinal profile that is such that the final longitudinal profile passes through the two remarkable points.
摘要:
A method for generating a trimming setpoint for an ophthalmic lens for it to be mounted in a surround of a spectacle frame, includes: a) acquiring the shape of a first longitudinal profile of the surround, b) constructing, on a two-dimensional projection of the first longitudinal profile, at least two predetermined geometrical figures, by adjusting their dimensions to those of the two-dimensional projection, c) calculating differences between the two-dimensional projection of the first longitudinal profile and each of the predetermined geometrical figures, d) from the target geometrical figures, each of which has an associated trimming parameter, selecting the target geometrical figure that is closest to the first longitudinal profile according to the differences, e) calculating the trimming setpoint according to the shape of the first longitudinal profile and the trimming parameter associated with the selected target geometrical figure.
摘要:
A predictive calculation method for calculating the shape of a cross-section of an engagement ridge of an ophthalmic lens obtained by beveling the lens with a beveling grindwheel driven in accordance with an initial path setting. The method includes the following steps: acquiring the initial path setting for the beveling grindwheel relative to the lens; determining at least two approximations (Sii, Sij) of the shape of the cross-section under consideration of the engagement ridge, the approximations being deduced from the intersection between the beveling grindwheel and the ophthalmic lens when the beveling grindwheel is situated at two distinct positions of the initial path setting; determining the intersection between these two approximations; and deducing therefrom the shape (Si) of the cross-section under consideration of the engagement ridge.
摘要:
A predictive calculation method for calculating the shape of a cross-section of an engagement ridge of an ophthalmic lens obtained by beveling the lens with a beveling grindwheel driven in accordance with an initial path setting. The method includes the following steps:acquiring the initial path setting for the beveling grindwheel relative to the lens;determining at least two approximations (Sii, Sij) of the shape of the cross-section under consideration of the engagement ridge, the approximations being deduced from the intersection between the beveling grindwheel and the ophthalmic lens when the beveling grindwheel is situated at two distinct positions of the initial path setting;determining the intersection between these two approximations; anddeducing therefrom the shape (Si) of the cross-section under consideration of the engagement ridge.