Patent ID: 8500273

Claim:
A soft contact lens for treating ametropia comprising the following circumferential zones: an optical zone in the center of the lens having a back curvature defined by a first optical base curve, a front curvature defined by a first optical front curve, a minimum axial thickness, and a maximum axial thickness, wherein the maximum axial thickness of the optical zone is at the center of the optical zone and the thickness of the optical zone decreases toward an outer edge of the optical zone; a pressure control zone extending radially outwardly from the optical zone, the pressure control zone having a back curvature defined by a pressure control base curve, a front curvature defined by pressure control front curve, a minimum axial thickness, and a maximum axial thickness, wherein the minimal axial thickness of the pressure control zone is in a radially central portion of the pressure control zone and the axial thickness of the pressure control zone increases radially from the central portion of the pressure control zone toward the optical zone and toward the peripheral zone; and an alignment zone extending radially outwardly from the pressure control zone, the alignment zone having a back curvature defined by alignment base curve, a front curvature defined by alignment front curve, a minimum axial thickness, and a maximum axial thickness, wherein the maximum axial thickness of the alignment zone is in a radially central portion of the alignment zone and the axial thickness of the alignment zone decreases from the central portion of the alignment zone toward the pressure control zone, wherein the minimum axial thickness of the pressure control zone is less than the minimum axial thickness of the optical zone and the minimum axial thickness of the alignment zone, and, wherein the optical zone and the pressure control zone have a thickness drop of between 0.03 mm and 1 mm, and the pressure control zone and the alignment zone have a thickness drop of between 0.03 mm and 1 mm, and wherein the contact lens is pliable and is made from a material containing between 20% and 70% water.