Spectacle lens for half-eye spectacles
AssigneeOptische Werke G. Rodenstock
InventorRudolf Barth
Life of this patent
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Abstract
A spectacle lens for half-eye spectacles is described which in accordance with the present invention has at least one aspherical surface whose surface focal power increased progressively from the upper rim area of the spectacle lens towards the lens bottom. In a preferred version example, the spectacle lens has a prismatic power of zero in the upper rim area. In a further preferred version example, the power of the spectacle lens increases progressively from a value other than zero in the upper rim towards the lens bottom.
Claims20
A spectacle lens for half-eye spectacles, the lens having a front surface and a rear surface facing the eye and defining an upper rim, at least the front surface having a progressive zone below the upper rim and a reading portion below the progressive zone, the lens defining a main meridian including a distance reference point above the upper rim and a near reference point below the upper rim, the lens focal power increasing progressively from an area of the upper rim along the main meridian to a value in the reading portion which the wearer requires for near vision, said front surface being aspherical and having a surface focal power which contributes to the increasing focal power, the radius of curvature for said front surface of lines formed from the intersection of planes orthogonal to the main meridian decreasing throughout the entirety of the progressive zone with increasing distance from the main meridian at least in a region surrounding the main meridian.
A spectacle lens for half-eye spectacles as set forth in claim 14 wherein the other of said surfaces is spherical.
A spectacle lens for half-eye spectacles, the lens having a front surface and a rear surface facing the eye and defining an upper rim, at least the rear surface having a progressive zone below the upper rim and a reading portion below the progressive zone, the lens defining a main meridian including a distance reference point above the upper rim and a near reference point below the upper rim, the lens focal power increasing progressively from an area of the upper rim along the main meridian to a value in the reading portion which the wearer requires for near vision, said rear surface being aspherical and having a surface focal power which contributes to the increasing focal power, the radius of curvature for said front surface of lines formed from the intersection of planes orthogonal to the main meridian increasing throughout the entirety of the progressive zone with increasing distance from the main meridian at least in a region surrounding the main meridian.
Dependencies are inferred from the claim text.