| 摘要 |
Ophthalmic no-line progressive addition lenses (10) for spectacles are provided with increased sizes of usable intermediate and near addition zones (18, 16). A preferred lens (10) of the present invention comprises a distance zone (14), one or more intermediate addition zones (18) and a near add zone (16), wherein each of the zones (14, 18, 16) has a generally spherical base curve. The intermediate and near addition zones (18, 16) are combined with the distance zone (14) by connecting wedges (20) which have aspheric base curves. The intermediate and near addition zones (18, 16) are preferably defined and separated by zones of inflection elimination (22) which are generally, radially equidistant from the optical center of the lens (10). An aspheric fringe (24) is used to flatten the peripheral area of the bottom portion (28) of the lens (10), thereby providing a thin and cosmetically acceptable lens (10).
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