Progressive spectacle lens having two aspherical progressive surfaces
AssigneeRodenstock GmbH
InventorsWalter Haimerl, Herbert Pfeiffer, Gregor Esser, Helmut Altheimer
Life of this patent
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Abstract
A progressive spectacle lens having two aspherical and in particular progressive surfaces, i.e. surfaces contributing to the rise in the effect (addition Add.) from the distance vision portion to the near vision portion, in which the sagittal heights zi=zi(x,y) of at least one (i) progressive surface (i=1,2) are chosen such that the sagittal height z of this respective surface at the edge of the spectacle lens given by yi=fi1(x) for y≧0 and yi=fi2(x) for y<0 assume predefined values without this surface (i) or the other surface (j) having a reversal of curvature forming a supporting edge.
Claims30
A progressive spectacle lens having two progressive surfaces contributing to a rise in effect Add. from a distance portion to a near portion, wherein the effect rises along a main line from the distance portion to the near portion, and the main line is formed as a curve which curves toward a side of a wearer's nose, and wherein the main line curve between the distance portion and the near portion is offset differently on the front surface than on the eye-side surface of the lens.
Dependencies are inferred from the claim text.