Patent ID: 7216977

Claim:
An ophthalmic lens with progressive addition of spherical power, the lens possessing a far vision zone (VL), a near vision zone (VP), and an intermediate vision zone (VI) situated between the two preceding zones, these three zones being crossed by a main progression meridian (MM′) along which the spherical refractive power (Pu) of the lens varies progressively, said lens having optical corrective power defined in particular by: spherical power addition (ΔPu) equal to the variation in spherical refractive power between a reference point (L) of the far vision zone and a reference point (P) of the near vision zone (VP), these two points (P, L) being situated on the main progression meridian (MM′); nominal spherical power (ΔPn) equal to the spherical refractive power at said reference point (L) of the far vision zone (VL); and nominal astigmatism (An) equal to the cylindrical refractive power at said reference point (L) of the far vision zone (VL) of less than 1 diopter; the lens presenting horizontal prismatic refractive power (Prh) that varies progressively along the main progression meridian (MM′) with an addition of horizontal prismatic power (ΔPrh) greater than 2 prismatic diopters in absolute value, said addition of horizontal prismatic power (ΔPrh) being defined as the difference between the horizontal prismatic refractive power (Prh(L)) at the reference point (L) of the far vision zone and the horizontal prismatic refractive power (Prh(P′)) at the projection point (P′) of the reference point (P) of the near vision zone (VP) onto the vertical line passing through the reference point (L) of the far vision zone.