Orthokeratology lens with displaced shaping zone
A contact lens for application in practice of orthokeratology on an eye, including a curved shell having a concave surface and a convex surface. The concave surface includes a carrier zone and a back shaping zone, the back shaping zone having a first curvature and the carrier zone having at least one second curvature. The curved shell has a geometric center and the back shaping zone has a shaping zone center and the back shaping zone center is offset peripherally from the geometric center. The curved shell can have an overall diameter that approximates a corneal limbal diameter of the eye to which the contact lens is to be applied.
1. A contact lens for application in practice of orthokeratology on an anterior corneal surface of an eye, comprising:
a curved shell having a concave surface and a convex surface, the concave surface including a carrier zone and a back shaping zone, the back shaping zone having a first spherical or toric curvature and the carrier zone having at least one second spherical or toric curvature different from the first spherical or toric curvature;
the curved shell adapted to shape an anterior corneal surface by physical interaction between the back shaping zone and the anterior corneal surface whereby refractive error of the eye is temporarily or permanently reduced;
the curved shell having a geometric center and the back shaping zone having a shaping zone center, the back shaping zone center being offset peripherally from the geometric center; and
the curved shell defines structure that stabilizes rotation of the contact lens relative to the eye.
2. The contact lens as claimed in claim 1 , wherein the at least one second spherical or toric curvature further comprises a second curve and the second curve is centered on the shaping zone center.
3. The contact lens as claimed in claim 1 , wherein the at least one second spherical or toric curvature further comprises a second curve and the second curve is centered on the geometric center.
4. The contact lens as claimed in claim 1 , wherein the contact lens is a reverse curve design.
5. The contact lens as claimed in claim 1 , wherein the contact lens comprises a three curve design.
6. The contact lens as claimed in claim 1 , wherein the contact lens comprises a four curve design.
7. The contact lens as claimed in claim 1 , wherein the overall diameter approximates a corneal limbal diameter of the eye to which the contact lens is to be applied.
8. The contact lens as claimed in claim 1 , wherein the overall diameter is in a range between 10.5 and 13.0 millimeters.
9. The contact lens as claimed in claim 1 , wherein the overall diameter is in a range between 10.5 and 12.5 millimeters.
10. The contact lens as claimed in claim 1 , wherein the overall diameter is in a range between 11.0 and 12.0 millimeters.
11. The contact lens as claimed in claim 1 , further comprising an orientation marker thereon.
12. The contact lens as claimed in claim 1 , wherein the structures that stabilize rotation of the contact lens relative the eye comprise a superior thin zone and an inferior thin zone.