Ophthalmic lens
A progressive multifocal ophthalmic lens has a complex surface having a prism reference point, a fitting cross, a progression meridian having a power addition greater than or equal to 1.5 diopters. The lens has, under conditions when being worn: - a reduced root mean square, normalized to the additi...
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Zusammenfassung: | A progressive multifocal ophthalmic lens has a complex surface having a prism reference point, a fitting cross, a progression meridian having a power addition greater than or equal to 1.5 diopters. The lens has, under conditions when being worn: - a reduced root mean square, normalized to the addition prescription, of less than 0.65 microns per diopter in a zone delimited by a circle centred on the prism reference point and with a diameter corresponding to a sweep of vision of 80°, - a progression length of less than or equal to 25°, and - a difference in normalized reduced root mean square between pairs of symmetrical points relative to a vertical axis passing through the fitting cross of less than 0.12 microns per diopter in a zone delimited by a semi-circle centred on the fitting cross and with a radius corresponding to raising viewing by 25°. |
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