Contact lens for keratoconus

摘要

The present invention is directed to a non-deforming contact lens for keratoconus patients having a displaced central zone. In particular, the central zone is displaced from the geometric center of the lens. The shape of the central zone is egg or spoon-shaped and is rotationally asymmetrical with one semi-meridian that is shorter than a corresponding semi-meridian. An intermediate transition zone is formed integral with the periphery of the central zone, and a peripheral zone is formed integral with the periphery of the intermediate transition zone, forming a round contact lens.

主权项

1. A contact lens for keratoconus having a posterior surface facing toward an eye having at least three zones, comprising:
a central zone displaced from the two-dimensional geometric center of the contact lens in the z direction, wherein the central zone is rotationally asymmetrical having a meridian with a first semi-meridian shorter in radius than a corresponding second semi-meridian; an intermediate transition zone formed integral with a periphery of the central zone; and a peripheral zone formed integral with a periphery of the intermediate transition zone.