| 摘要 |
An ophthalmic lens having a complex surface and a toric or spherical surface is represented in a model using a prism reference point and a prescription point on the complex surface, the normal to the complex surface at the prism reference point, the local characteristics of the complex surface at the prescription point or around the prescription point, lens thickness measured along the axis defined by the normal to the complex surface, the plane tangential to the toric or spherical surface on the axis, and the curvatures of the toric or spherical surface. Representation of the lens in this model allows calculation of the toric or spherical surface without knowing all the characteristics of the complex surface. Calculations are simpler for the fitting of the lens into frames adapted to the wearer.
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