Laminated composite lens
A composite lens comprises an anterior rigid gas permeable layer, and an annulus of soft material bonded to a posterior surface of the anterior rigid gas permeable layer, wherein a central zone of the composite lens is rigid and without a soft layer, wherein a peripheral zone of the composite lens is generally rigid in its anterior aspect and soft in its posterior aspect.
1. A composite lens, comprising:
a central zone and a peripheral zone;
an anterior rigid layer; and
an annulus of soft material bonded to a posterior surface of the anterior rigid layer, the annulus having regions that vary in thickness;
wherein the regions that vary in thickness are substantially orthogonal such that a deepest region and a shallowest regions are substantially 90° apart.
2. The composite lens of claim 1 , wherein providing an annulus having regions that vary in thickness reduces flexure in the rigid layer.
3. The composite lens of claim 1 , wherein providing an annulus having regions that vary in thickness provides rotational stability due to conformance to ocular contour by the non-uniform thickness of the annulus.
4. The composite lens of claim 1 , wherein the thickness of the annulus varies to accommodate scleral contour.
5. The composite lens of claim 1 , wherein the thickness of the annulus varies to accommodate peripheral corneal contour.
6. The composite lens of claim 1 , wherein a region of the annulus that varies in thickness is located in the scleral region.
7. The composite lens of claim 1 , wherein a region of the annulus that varies in thickness is located in the corneo-scleral region.
8. The composite lens of claim 1 , wherein a region of the annulus that varies in thickness is located in the corneal region.
9. The composite lens of claim 1 , wherein a thickness of the soft annulus varies to accommodate ocular contour.
10. The composite lens of claim 1 , wherein the central zone is rigid and without a posterior soft layer.
11. The composite lens of claim 1 , wherein a peripheral aspect of the central zone is rigid in its anterior aspect and soft in its posterior aspect.
12. The composite lens of claim 1 , wherein the peripheral zone is soft and without an anterior rigid layer.
13. The composite lens of claim 1 , wherein the central zone of the composite lens is 7 mm to 16 mm in diameter.
14. The composite lens of claim 1 , wherein the central zone of the composite lens is 9 mm to 13 mm in diameter.
15. The composite lens of claim 1 , wherein a radial width of the soft annulus is 250 microns to 5 mm.