MULTIFOCAL LENS COMBINING THE ADVANTAGES OF PROGRESSIVE ADDITION LENSES AND DIFFRACTIVE LENSES

摘要

A multifocal lens (22) having far and near vision zones, the multifocal lens comprising a combination of a progressive addition lens and a diffractive element (26), wherein: said progressive addition lens is a substrate (24) carrying said diffractive element, which is in the form of a modulation on the surface of the substrate; said substrate has refractive power distribution defining far and near vision zones, selected in accordance with respective prescribed values of optical power required for the patient's eye at his distance and reading vision, and an intermediate transition region between the far and near vision zones; and said modulation produces locally variable optical power addition to the optical power of the substrate, said locally variable optical power addition being maximal within said intermediate transition region and decreasing gradually towards the far and near vision zones of the substrate, said far and near vision zones of the multifocal lens being thereby wider than said far and near vision zones of the substrate. 3514 כ" ו בכסלו התשס" ג - December 1, 20