| 摘要 |
The present invention provides a myopia and/or astigmatism-correcting contact lens for correcting myopia and/or astigmatism based on the alteration in the shape of a patient's cornea. The myopia and/or astigmatism-correcting contact lens comprises a pressure zone having a first surface defined by the inner surface of the contact lens located on the side of the patient's cornea and positioned at the center of the contact lens. The first surface is formed in a concave shape having a curvature less than that of the central surface of the patient's cornea. The contact lens further includes a relief zone having a concave-shaped second surface defined by the inner surface of the contact lens located on the side of the patient's cornea and positioned at the periphery of the pressure zone, and an anchor zone having a concave-shaped third surface defined by the inner surface of the contact lens on the side of the patient's cornea and positioned at the periphery of the relief zone. The first surface has a curvature determined based on the shape of the patient's cornea to induce a specific desired alteration in the shape of the patient's cornea. Further, each of the curvatures of the first, second and third surfaces is arranged to satisfy the following formulas, <?in-line-formulae description="In-line Formulae" end="lead"?>RC=BC +7.0~9.0 D (diopter), and<?in-line-formulae description="In-line Formulae" end="tail"?> <?in-line-formulae description="In-line Formulae" end="lead"?>AC=BC +2.0~4.0 D<?in-line-formulae description="In-line Formulae" end="tail"?> where BC is the curvature of the first surface, RC is the curvature of the second surface, and AC is the curvature of the third surface.
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