Progressive multifocal ophthalmic lens designed to inhibit progressive myopia of the wearer

A method of providing a lens as a progressive multifocal ophthalmic lens for positioning in front of an eye under usual wear conditions having a power addition prescription and an astigmatism prescription, the method comprising:

• providing a far vision point on the lens, such that a far-vision zone is around the far vision point, the far-vision zone corresponding to an intersection of the lens and a far vision cone, the far vision cone being a right circular cone with an axis of the far vision cone passing through a center of rotation of the eye and the far vision point, an aperture of the far vision cone being greater than or equal to
• PL
• 9
• and smaller than or equal to
• PL
• 3
• ,
• with PL as an angular progression length of the lens;
• providing a near vision point on the lens, such that a near-vision zone is around the near vision point, the near-vision zone corresponding to an intersection of the lens and a near vision cone, the near vision cone being a right circular cone with an axis of the near vision cone passing through the center of rotation of the eye and the near vision point, an aperture of the near vision cone being greater than or equal to
• PL
• 9
• and smaller than or equal to
• PL
• 3
• ;
• and
• providing an intermediate vision point on the lens, such that an intermediate-vision zone is around the intermediate vision point, the intermediate-vision zone corresponding to an intersection of the lens and an intermediate vision cone, the intermediate vision cone being a right circular cone with an axis of the intermediate vision cone passing through the center of rotation of the eye and the intermediate vision point, an aperture of the intermediate vision cone being greater than or equal to
• PL
• 9
• and smaller than or equal to
• PL
• 3
• ,
• and the intermediate vision point is positioned between the far vision point and the near vision point, so that:
• ⅓|αF−αN|≦|≦|αF−αI|≦⅔|αF−αN|;
• and
• min(βN,βF)≦βI≦max(βN,βF),
• with αF, βF, αN, βN, αI and βI as angular coordinates of respectively the far vision point, the near vision point and the intermediate vision point in a Fick system;
• in which a resulting astigmatism in the far-vision and near-vision zones is smaller than or equal to
• Add
• 3
• ,
• with Add as a value of the power addition prescription, and
• a resulting astigmatism in the intermediate-vision zone is greater than or equal to 0.4×Add and smaller than or equal to 2×Add.

A method for providing a progressive multifocal ophthalmic lens comprising:

• obtaining wearer data comprising at least prescription information associated with a wearer in need of the progressive multifocal ophthalmic lens,
• obtaining an initial set of data about the wearer's vision, the initial set of data including at least a fitting cross, a near vision point and a main meridian line passing through the fitting cross and the near vision point,
• producing by an optimization surface data for the progressive multifocal ophthalmic lens, such that with the surface data, an intermediate vision zone is provided that contains resulting astigmatism with or without optical aberrations so that the wearer under usual wear conditions when provided the progressive multifocal ophthalmic lens will look through another part of the progressive multifocal ophthalmic lens rather than the intermediate vision zone,
• the producing includes lowering of a viewing direction below the fitting cross, and positioning an intermediate vision point in accordance with (1):
• αF−αI≦0.5×|αF−αN (1),
• in which αF, αN, and αI are each an angular coordinate of respectively a far vision point, the near vision point and the intermediate vision point in a Fick system,
• wherein the surface data further provides a near vision zone and a far vision zone, the intermediate vision zone between the far vision and the near vision zones, such that optical quality to the wearer is higher when looking through the near vision and far vision zones as compared with looking through the intermediate vision zone and the resulting astigmatism in the intermediate zone is greater than or equal to 0.4×Add and smaller than or equal to 2×Add, in which Add is a value of a power addition prescription.