Abstract: The lens presents horizontal prismatic refractive power that varies progressively along the main progression meridian (MM?) with the addition of horizontal prismatic power being greater than 2 prismatic diopters in absolute value, this addition of horizontal prismatic power being defined by the difference between the horizontal prismatic refractive power at the reference point (L) of the far vision zone and the horizontal prismatic refractive power at the projection point (P?) of the reference point (P) of the near vision zone (VP) on the vertical line passing through the reference point (L) of the far vision zone.

Abstract: The lens presents horizontal prismatic refractive power that varies progressively along the main progression meridian (MM?) with the addition of horizontal prismatic power being greater than 2 prismatic diopters in absolute value, this addition of horizontal prismatic power being defined by the difference between the horizontal prismatic refractive power at the reference point (L) of the far vision zone and the horizontal prismatic refractive power at the projection point (P?) of the reference point (P) of the near vision zone (VP) on the vertical line passing through the reference point (L) of the far vision zone.

Abstract: A progressive multifocal ophthalmic lens having a far vision region, an intermediate vision region and a near vision region, a main meridian of progression passing through said three regions, and a power addition equal to a difference in mean sphere between a near vision region control point and a far vision region control point is provided. The lens has a progression length less than 12 mm, defined as the vertical distance between a mounting center and a point on the meridian where mean sphere is greater than mean sphere at the far vision control point by 85% of the power addition value.

Abstract: The invention relates to a multifocal ophthalmic lens, comprising an aspherical surface with a mean sphere and a cylinder at every point thereof, characterized by the equation: L<1/(−0.031×R2+0.139×R+0.014) where L is equal to the ratio (Smax−Smin)/gradSmax, the ratio of the difference between the maximum and minimum values of the mean sphere in a region of a 40 mm diameter circle centered on the geometric center of the lens, this region being limited by vertical straight lines at 1 mm from this center on the temporal side and at 4 mm from this center on the nasal side, on the one hand, to the maximum value of the gradient of the mean sphere in this same region, on the other hand, and where R is equal to the ratio Cmax/(Smax−Smin), the ratio of the maximum cylinder value inside said circle to the difference between the maximum and minimum values of the mean sphere in said region.

Abstract: A progressive multifocal ophthalmic lens having a far vision region, an intermediate vision region and a near vision region, a main meridian of progression passing through said three regions, and a power addition equal to a difference in mean sphere between a near vision region control point and a far vision region control point is provided. The lens has a progression length less than 12 mm, defined as the vertical distance between a mounting center and a point on the meridian where mean sphere is greater than mean sphere at the far vision control point by 85% of the power addition value. To ensure excellent optical performance of the lens despite this short length of progression, the ratio between the product of cylinder times the norm of sphere gradient, and the square of power addition is less than 0.08 mm−1 at every point within a 40 mm diameter disc centered on the center of the lens. Additionally, cylinder within that part of the disc situated above the mounting center is less than 0.

Abstract: A progressive multifocal ophthalmic lens having a far vision region, an intermediate vision region and a near vision region, a main meridian of progression passing through said three regions, and a power addition equal to a difference in mean sphere between a near vision region control point and a far vision region control point is provided. The lens has a progression length less than 12 mm, defined as the vertical distance between a mounting center and a point on the meridian where mean sphere is greater than mean sphere at the far vision control point by 85% of the power addition value. To ensure excellent optical performance of the lens despite this short length of progression, the ratio between the product of cylinder times the norm of sphere gradient, and the square of power addition is less than 0.08 mm−1 at every point within a 40 mm diameter disc centered on the center of the lens. Additionally, cylinder within that part of the disc situated above the mounting center is less than 0.

Abstract: A progressive multifocal ophthalmic lens having a far vision region, an intermediate vision region and a near vision region, a main meridian of progression passing through said three regions, and a power addition equal to a difference in mean sphere between a near vision region control point and a far vision region control point is provided. The lens has a progression length less than 12 mm, defined as the vertical distance between a mounting center and a point on the meridian where mean sphere is greater than mean sphere at the far vision control point by 85% of the power addition value.

Abstract: The invention relates to a multifocal ophthalmic lens, comprising an aspherical surface with a mean sphere and a cylinder at every point thereof, characterized by the equation:

Abstract: There is provided a spectacle frame 1, having a least one corrective lens the characteristics of which do not vary over time and having telemetry means 5 which set off an alarm 9, 10 when the distance measured by the telemetry means is less than a predetermined preference distance. This reference distance can for example be set at between 20 and 50 cm depending on the spectacle wearer. A kit is also provided comprising a frame, telemetry means and an alarm. The spectacle frame can be prescribed for slowing down the evolution of acquired myopia in children who are starting to acquire myopia; here, the spectacle frame is provided with progressive multifocal lenses. The telemetry means and alarm incite the child to respect a sufficient working distance for close vision.

Abstract: In a progressive multifocal ophthalmic lens having an aspherical surface comprising a far vision region (VL), a near vision region (VP), an intermediate vision region, a main meridian of progression passing through these three regions, and a mounting center (CM), the far vision region includes an angular sector with its apex at the mounting center and a central angle of 110°, within which values of sphere and cylinder are less than or equal to 0.50 diopters, and a region of the lens above the near vision reference point and extending substantially up to the middle of the intermediate vision region has a maximum variation in values of cylinder 20 mm to both sides of the meridian limited to less than or equal to 0.30 diopters, and to less than or equal to 10% of the power addition of the lens. The lenses obtained, generally of power addition greater than or equal to 2.

Abstract: In a multifocal ophthalmic lens comprising an aspherical surface having at every point thereon a mean sphere and a cylinder, a far vision region, a near vision region, and an intermediate vision region, the length of progression i.e. the length over which lens power varies by a set amount in different regions of the lens, is short. To avoid distortion at the periphery of the lens which this would otherwise occasion, the isosphere and isocylinder lines are distributed over the surface of the lens so as to ensure variations in sphere are not too sudden along a 20 mm radius circle centered on the geometric center of the lens and variations in cylinder on the surface of the lens inside this circle are also very small. The lens has an enlarged near vision region and progression is less perceptible to the wearer.

Abstract: In a progressive multifocal ophthalmic lens providing excellent performance in the far vision region, good width of the near vision region and gentle progression in the intermediate vision region therebetween, the far vision region comprises an angular sector defined by two half-lines that intersect at the geometrical center of the lens forming an upwardly-directed angular segment with an included angle of preferably more than 145.degree. in which all points have a cylinder less than A/2 diopters, and constraints are applied governing the gentleness of progression in the intermediate vision region and the relative width of the near vision region.

Abstract: A progressive multifocal ophthalmic lens is provided having an aspherical surface comprising a distance vision portion, a near vision portion and an intermediate vision portion, in which the maximum mean sphere gradient value is situated in the intermediate vision portion of the principal meridian of progression of the lens, and the cylinder gradient over the whole aspherical surface of the lens is less than the product obtained by multiplying the power addition value at each point by a constant value coefficient.