Toric lens design
View Patent ↗This invention is related to contact lenses. In particular, the present invention is related to a toric contact lens design with thickness zones in the carrier portion of the lens for increased rotational stability.
1. A toric contact lens design comprising a central optical zone, a vertical meridian, a transition zone surrounding said central optical zone, and a carrier extending from said transition zone outward and having three thickness zones in said carrier, wherein the thickness zones are designed to achieve rotational stability, wherein said thickness zones are symmetrical across the vertical meridian on the sides of said lens design, wherein the slope of the thickness profile of the second zone is a linear function, wherein the thickness profile is measured along angular meridians radiating from the central optical zone, and wherein the thickness change along each of the second zone angular meridians is equal to or less than 10% of the maximum thickness of the meridian.
2. The design of claim 1 , wherein the boundary between the first zone and second zone is between about 15 degrees from the vertical meridian and about 45 degrees from the vertical meridian.
3. The design of claim 1 , wherein the boundary between the third zone and second zone is between about 30 degrees from the vertical meridian and about 60 degrees from the vertical meridian.
4. The design of claim 1 , wherein there is a relatively consistent thickness section at each angular meridian in zones one and two.
5. The design of claim 1 , wherein a thickness range from the upper boundary to the lower boundary of the second zone is between about 0.065 mm to about 0.45 mm.
6. The lens created by claim 1 .
7. The design of claim 1 , further comprising a second transition zone at the edge of the lens.
8. A toric contact lens design comprising a central optical zone, a vertical meridian, a transition zone surrounding said central optical zone, a carrier extending from said transition zone outward and three thickness zones in said carrier, wherein the thickness zones are designed to achieve rotational stability, wherein said thickness zones are symmetrical across the vertical meridian on the sides of said lens design, wherein the slope of the thickness profile of the second zone gradually increases and subsequently decreases from the upper boundary to the lower boundary, wherein the thickness profile is measured along angular meridians radiating from the central optical zone, and wherein the thickness change along each of the second zone angular meridians is equal to or less than 10% of the maximum thickness of the meridian.
9. The design of claim 8 , wherein the boundary between the first zone and second zone is between about 15 degrees from the vertical meridian and about 45 degrees from the vertical meridian.
10. The design of claim 8 , wherein the boundary between the third zone and second zone is between about 30 degrees from the vertical meridian and about 60 degrees from the vertical meridian.
11. The design of claim 8 , wherein there is a relatively consistent thickness section at each angular meridian in zones one and two.
12. The design of claim 8 , wherein a thickness range from the upper boundary to the lower boundary of the second zone is between about 0.065 mm to about 0.45 mm.
13. The lens created by claim 8 .
14. The design of claim 8 , further comprising a second transition zone at the edge of the lens.
15. A toric contact lens design comprising a central optical zone, a vertical meridian, a transition zone surrounding said central optical zone, a carrier extending from said transition zone outward and a plurality of thickness zones in said carrier, wherein the thickness zones are designed to achieve rotational stability, wherein said thickness zones are symmetrical across the vertical meridian on the sides of said lens design, wherein width of a relatively consistent thickness is at least 30% of the zone width, wherein the thickness profile is measured along angular meridians radiating from the central optical zone, and wherein the thickness change along each of the second zone angular meridians is equal to or less than 10% of the maximum thickness of the meridian.
16. The design of claim 15 , wherein said plurality of said thickness zones further comprises three thickness zones.
17. The design of claim 16 , wherein the boundary between the first zone and second zone is between about 15 degrees from the vertical meridian and about 45 degrees from the vertical meridian.
18. The design of claim 16 , wherein the boundary between the third zone and second zone is between about 30 degrees from the vertical meridian and about 60 degrees from the vertical meridian.
19. The design of claim 16 , wherein there is a relatively consistent thickness section at each angular meridian in zones one and two.
20. The design of claim 16 , wherein a thickness range from the upper boundary to the lower boundary of the second zone is between about 0.065 mm to about 0.45 mm.
21. The lens created by claim 15 .
22. The design of claim 15 , further comprising a second transition zone at the edge of the lens.
23. A toric contact lens design comprising a central optical zone, a carrier extending from said central optical zone outward and three thickness zones in said carrier, wherein the thickness zones are designed to achieve rotational stability, wherein the slope of the thickness profile of the second zone is a linear function, wherein the thickness profile is measured along angular meridians radiating from the central optical zone, and wherein the thickness change along each of the angular meridians in a second thickness zone is equal to or less than 10% of the maximum thickness of the meridian.
24. The design of claim 23 , wherein the boundary between the first and second zone is between about 15 degrees from the vertical meridian and about 45 degrees from the vertical meridian.
25. The design of claim 23 , wherein the boundary between the third zone and second zone is between about 30 degrees from the vertical meridian and about 60 degrees from the vertical meridian.
26. The design of claim 23 , wherein a thickness range from the upper boundary to the lower boundary of the second zone is about 0.065 mm to about 0.45 mm.
27. The design of claim 23 , wherein there is a relatively consistent thickness section at each angular meridian in zones one and two.
28. The lens created by claim 23 .
29. The design of claim 23 , further comprising a transition zone at the edge of the lens.
30. A toric contact lens design comprising a central optical zone, a carrier extending from said central optical zone outward and three thickness zones in said carrier, wherein the thickness zones are designed to achieve rotational stability, wherein the slope of the thickness profile of the second zone gradually increases and subsequently decreases from the upper boundary to the lower boundary, wherein the thickness profile is measured along angular meridians radiating from the central optical zone, and wherein the thickness change along each of the second zone angular meridians is equal to or less than 10% of the maximum thickness of the meridian.
31. The design of claim 30 , wherein the boundary between the first and second zone is between about 15 degrees from the vertical meridian and about 45 degrees from the vertical meridian.
32. The design of claim 30 , wherein the boundary between the third zone and second zone is between about 30 degrees from the vertical meridian and about 60 degrees from the vertical meridian.
33. The design of claim 30 , wherein there is a relatively consistent thickness section at each angular meridian in zones one and two.
34. The design of claim 30 , wherein a thickness range from the upper boundary to the lower boundary of the second zone is about 0.065 mm to about 0.45 mm.
35. The lens created by claim 30 .
36. The design of claim 30 , further comprising a transition zone at the edge of the lens.
37. A toric contact lens design comprising a central optical zone, a carrier extending from said central optical zone outward and a plurality of thickness zones in said carrier, wherein the thickness zones are designed to achieve rotational stability, wherein width of a relatively consistent thickness is at least 30% of the zone width, wherein the thickness profile is measured along angular meridians radiating from the central optical zone, and wherein the thickness change along each of the angular meridians in a second zone is equal to or less than 10% of the maximum thickness of the meridian.
38. The design of claim 37 , wherein said plurality of said thickness zones further comprises three thickness zones.
39. The design of claim 38 , wherein the boundary between the first zone and second zone is between about 15 degrees from the vertical meridian and about 45 degrees from the vertical meridian.
40. The design of claim 38 , wherein the boundary between the third zone and second zone is between about 30 degrees from the vertical meridian and about 60 degrees from the vertical meridian.
41. The design of claim 38 , wherein there is a relatively consistent thickness section at each angular meridian in zones one and two.
42. The design of claim 38 , wherein a thickness range from the upper boundary to the lower boundary of the second zone is between about 0.065 mm to about 0.45 mm.
43. The lens created by claim 37 .
44. The design of claim 37 , further comprising a second transition zone at the edge of the lens.