| 摘要 |
In a progressive multifocal ophthalmic lens having an aspherical surface comprising a far vision region (VL), a near vision region (VP), an intermediate vision region, a main meridian of progression passing through these three regions, and a mounting center (CM), the far vision region includes an angular sector with its apex at the mounting center and a central angle of 110.degree., within which values of sphere and cylinder are less than or equal to 0.50 diopters, and a region of the lens above the near vision reference point and extending substantially up to the middle of the intermediate vision region has a maximum variation in values of cylinder 20 mm to both sides of the meridian limited to less than or equal to 0.30 diopters, and to less than or equal to 10% of the power addition of the lens. The lenses obtained, generally of power addition greater than or equal to 2.50, have wider near and intermediate vision regions, as well as a distribution of sphere and cylinder which is as homogeneous as possible over the complete surface of the lens.
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