Multifocal ophthalmic lens

• US 7,063,422 B2
• Filed: 04/12/2004
• Issued: 06/20/2006
• Est. Priority Date: 04/16/2003
• Status: Active Grant

• Current Assignee: Alcon Incorporated
• Original Assignee: Novartis Ag
• Inventors: Lindacher, Joseph Michael
• Primary Examiner(s): Schwartz, Jordan
• Assistant Examiner(s): STULTZ, JESSICA T
• Application Number:
  US10/822,564
• Publication Number:
  US 20040207807A1
• Time in Patent Office: 799 Days
• Field of Search: 351/161
• US Class Current: 351/161
• CPC Class Codes: A61F 2/1613 having special lens configurations, e.g. multipart lenses; having particular optical properties, e.g. pseudo-accommodative lenses, lenses having aberration corrections, diffractive lenses, lenses for variably absorbing electromagnetic radiation, lenses having variable focus
• CPC Class Codes: G02C 7/028 Special mathematical design techniques
• CPC Class Codes: G02C 7/043 Translating type
• CPC Class Codes: G02C 7/045 Sectorial configuration
• CPC Class Codes: G02C 7/048 Means for stabilising the orientation of lenses in the eye

Abstract

This invention is generally related to vision corrections by means of multifocal ophthalmic lenses or by means of corneal refractive surgery. In particular, the present invention provides a multifocal contact lens, a multifocal intraocular lens, a method for making a multifocal ophthalmic lens (contact lens and intraocular lens), and a method of correcting presbyopia by reshaping the cornea of an eye.

Claims

1. A contact lens, comprising an anterior surface and an opposite posterior surface, wherein at least one of the anterior and posterior surface includes a vertical meridian, a horizontal meridian, and a central optical zone, wherein the central optical zone has a top boundary, a bottom boundary, a distance vision zone and a rotationally-asymmetrical progressive zone adjacent to the distance vision zone,

wherein the distance vision zone is located in the upper portion of the central optical zone and provides a distance power for distance vision correction,

wherein the rotationally-asymmetrical progressive zone is located in the lower portion of the central optical zone and provides a variable intermediate vision correction and near vision correction,

wherein the rotationally-asymmetrical progressive zone has a surface that provides a power addition profile, along the upper vertically radiating semi-meridian, which is defined by two or more linear functions of equation (1) or by equation (2) or equation

$\begin{array}{c}\{\begin{array}{c}p\end{array}\end{array}$

( x ) = b 1 + k 1 ⁢

x ⁢

0 ≤

x <

x 1 p ⁡

( x ) = b 2 + k 2 ⁢

x ⁢

x 1 ≤

x <

x 2 ⋮

p ⁡

( x ) = b i + k i ⁢

x ⁢

x i - 1 ≤

x <

x i ⋮

( 1 ) p ⁡

( x ) = A 2 ·

cos ⁡

( x X o ⁢

π

) + A 2 ( 2 ) p ⁡

( x ) = A ·

[ 1 - ( x X 0 ) n ] ( 3 )

in which p(x) is an added power at a radial distance of x from the radial center;

b_i is a coefficient which is the intercept of a linear line;

k_i is the rate of change of the added power as function of the distance from the radial center;

A is the maximum added power;

X_o is a radial distance between the radial center and the optical axis; and

n is any number which can be an integer or non-integer larger than 1 but smaller than or equal to 10.

2. The contact lens of claim 1, wherein the rotationally-asymmetrical progressive zone has an upper boundary, a lower boundary, a radial center, an upper vertically radiating semi-meridian and a lower vertically radiating semi-meridian, and wherein the rotationally-asymmetrical progressive zone further has a surface that provides a power profile that increases, along the upper vertically radiating semi-meridian, from the distance power at the upper boundary to a near power at the radial center and remains substantially constant from the radial center to a point near the lower boundary along the lower vertically radiating semi-meridian.

3. The contact lens of claim 2, wherein the anterior surface includes the vertical meridian, the horizontal meridian, and the central optical zone having the top boundary, the bottom boundary, the distance vision zone and the rotationally-asymmetrical progressive zone adjacent to the distance vision zone.

4. The contact lens of claim 2, wherein the central optical zone is a circular zone which is concentric with the geometric center of the anterior or posterior surface, or the center of which is deviated from the geometric center of the anterior or posterior surface by up to 2 mm.

5. The contact lens of claim 4, wherein the circular central optical zone is concentric with the geometric center of the anterior or posterior surface.

6. The contact lens of claim 3, wherein the distance zone extends downwardly from the top boundary of the central optical zone;

wherein the lower boundary line of the distance zone with the rotationally-asymmetrical progressive zone is at or slightly below a horizontal line passing through the center of the central optical zone and parallel with the horizontal meridian, at least in its central portion.

7. The contact lens of claim 6, wherein the apex of the distance vision zone coincides with the center of the central optical zone and wherein the optical axis of the lens passes through the apex of the distance vision zone and the center of the optical zone of the posterior surface.

8. The contact lens of claim 3, wherein the radial center is located below the center of the central optical zone and on the vertical meridian or a line parallel to the vertical meridian and passing through the center of the central optical zone, and wherein the distance between the radial center and the optical axis of the lens, the optical axis passing through the center of the central optical zone, is about 2.0 mm or less.

9. The contact lens of claim 3, wherein the central optical zone is characterized by that the lateral separation between images from the distance vision zone and the rotationally-asymmetrical progressive zone is minimized or eliminated so as to minimize or eliminate ghost images.

10. The contact lens of claim 9, wherein a first line passing through the radial center and the center of curvature at the radial center intersects the optical axis of the lens, wherein the intersection point is within 2 mm or less of the center of curvature at the apex of the posterior surface.

11. The contact lens of claim 10, wherein the intersection point of the first line with the optical axis is within 0.5 mm or less of the center of curvature at the apex of the posterior surface.

12. The contact lens of claim 3, wherein the rotationally-asymmetrical progressive zone is tangent to the distance vision zone at any point along the upper and lower boundaries of the rotationally-asymmetrical progressive zone.

13. The contact lens of claim 3, wherein the contact lens comprises one or more orientation or stabilization features.

14. The contact lens of claim 13, wherein said one or more orientation/stabilization features are selected from the group consisting of:

a prism ballast or the like that uses a varying thickness profile to control the lens orientation;

a faceted surface in which parts of the lens geometry is removed to control the lens orientation;

a ridge feature which orients the lens by interacting with the eyelid;

double slab-off features which have a top slab-off zone and a bottom slab-off zone zones to maintain the lens orientation on the eye; and

non-prism ballast features in the peripheral zone of the lens, the peripheral zone surrounding the optical zone of the lens.

15. The contact lens of claim 13, wherein the contact lens comprises on the anterior surface of the lens a ramped ridge zone which is disposed below the optical zone and includes an upper boundary, a lower ramped boundary, a latitudinal ridge that extends outwardly from the anterior surface, and a ramp that extends downwardly from the lower ramped boundary and has a curvature or slope that provides a varying degree of interaction between the ramped ridge zone and the lower eyelid of an eye depending on where the lower eyelid strikes the ramped ridge zone.

16. The contact lens of claim 13, wherein the anterior surface comprises a blending zone extending outwardly from the central optical zone, a peripheral zone surrounding the blending zone, and an boundary zone circumscribing and tangent to the peripheral zone, wherein the blending zone has a surface which ensures that the peripheral zone, the blending zone and the central optical zone are tangent to each other, wherein the peripheral zone has a surface that, in combination with the posterior surface, provides in the peripheral zone of the lens a thickness profile which is characterized (1) by having a lens thickness which increases progressively from the top of the lens downwardly along each of the vertical meridian and lines parallel to the vertical meridian until reaching a maximum value at a position between the anterior optical zone and the boundary zone and then decreases to the boundary of the boundary zone, or (2) by having a mirror symmetry with respect to a plane cutting through the vertical meridian, by having a substantially constant thickness in a region around the horizontal meridian and by having a thickness which decreases progressively from the horizontal meridian to the top or bottom of the contact lens along each of the vertical meridian and lines parallel to the vertical meridian.

17. The contact lens of claim 2, wherein the contact lens is a hard or soft lens.

18. A contact lens, comprising an anterior surface and an opposite posterior surface, wherein at least one of the anterior and posterior surface includes a vertical meridian, a horizontal meridian, and a central optical zone, wherein the central optical zone has a top boundary, a bottom boundary, a distance vision zone and a rotationally-asymmetrical progressive zone adjacent to the distance vision zone,

wherein the distance vision zone is located in the upper portion of the central optical zone and provides a distance power for distance vision correction;

wherein the rotationally-asymmetrical progressive zone is located in the lower portion of the optical zone and provides a variable intermediate vision correction and near vision correction,

wherein the rotationally-asymmetrical progressive zone has an upper boundary, a lower boundary, a radial center, an upper vertically radiating semi-meridian and a lower vertically radiating semi-meridian, and wherein the rotationally-asymmetrical progressive zone further has a surface that provides a power profile that increases, along the upper vertically radiating semi-meridian, from the distance power at the upper boundary to a near power at the radial center and remains substantially constant from the radial center to a point near the lower boundary along the lower vertically radiating semi-meridian,

wherein the anterior surface includes the vertical meridian, the horizontal meridian, and the central optical zone having the top boundary, the bottom boundary, the distance vision zone and the rotationally-asymmetrical progressive zone adjacent to the distance vision zone,

wherein the anterior surface comprises a blending zone extending outwardly from the central optical zone, a peripheral zone surrounding the blending zone, and an boundary zone circumscribing and tangent to the peripheral zone, and

wherein the blending zone has a surface which ensures that the peripheral zone, the blending zone and the central optical zone are tangent to each other, wherein the peripheral zone has a surface that, in combination with the posterior surface, provides in the peripheral zone of the lens a thickness profile which is characterized (1) by having a lens thickness which increases progressively from the top of the lens downwardly along each of the vertical meridian and lines parallel to the vertical meridian until reaching a maximum value at a position between the anterior optical zone and the boundary zone and then decreases to the boundary of the boundary zone, or (2) by having a mirror symmetry with respect to a plane cutting through the vertical meridian, by having a substantially constant thickness in a region around the horizontal meridian and by having a thickness which decreases progressively from the horizontal meridian to the top or bottom of the contact lens along each of the vertical meridian and lines parallel to the vertical meridian.

19. The contact lens of claim 18, wherein the distance zone extends downwardly from the top boundary of the central optical zone;

wherein the lower boundary line of the distance zone with the rotationally-asymmetrical progressive zone is at or slightly below a horizontal line passing through the center of the central optical zone and parallel with the horizontal meridian, at least in its central portion.

20. The contact lens of claim 19, wherein the apex of the distance vision zone coincides with the center of the central optical zone and wherein the optical axis of the lens passes through the apex of the distance vision zone and the center of the optical zone of the posterior surface.

21. The contact lens of claim 18, wherein the radial center is located below the center of the central optical zone and on the vertical meridian, and wherein the distance between the radial center and the optical axis of the lens is about 2.0 mm or less.

22. The contact lens of claim 18, wherein the central optical zone is characterized by that the lateral separation between images from the distance vision zone and the rotationally-asymmetrical progressive zone is minimized or eliminated so as to minimize or eliminate ghost images.

23. The contact lens of claim 22, wherein a first line passing through the radial center and the center of curvature at the radial center intersects the optical axis of the lens, wherein the intersection point is within 2 mm or less of the center of curvature at the apex.

24. The contact lens of claim 18, wherein the rotationally-asymmetrical progressive zone is tangent to the distance vision zone at any point along the upper and lower boundaries of the rotationally-asymmetrical progressive zone.

25. The contact lens of claim 18, wherein the rotationally-asymmetrical progressive zone has a surface that provides a power addition profile, along the upper vertically radiating semi-meridian, which is defined by two or more linear functions of equation (1) or by equation (2) or equation (3)

$\begin{array}{c}\{\begin{array}{c}p\end{array}\end{array}$

( x ) = b 1 + k 1 ⁢

x ⁢

0 ≤

x <

x 1 p ⁡

( x ) = b 2 + k 2 ⁢

x ⁢

x 1 ≤

x <

x 2 ⋮

p ⁡

( x ) = b i + k i ⁢

x ⁢

x i - 1 ≤

x <

x i ⋮

( 1 ) p ⁡

( x ) = A 2 ·

cos ⁡

( x X o ⁢

π

) + A 2 ( 2 ) p ⁡

( x ) = A ·

[ 1 - ( x X 0 ) n ] ( 3 )

in which p(x) is an added power at a radial distance of x from the radial center;

b_i is a coefficient which is the intercept of a linear line;

k_i is the rate of change of the added power as function of the distance from the radial center;

A is the maximum added power;

X_o is a radial distance between the radial center and the optical axis; and

n is any number which can be an integer or non-integer larger than 1 but smaller than or equal to 10.

26. The contact lens of claim 18, wherein the intraocular lens is a phakic or aphakic intraocular lens.

27. The contact lens of claim 26, wherein the phakic or aphakic intraocular lens comprises haptics.

28. A method for producing a contact lens capable of correcting presbyopia, comprising the steps of designing the anterior surface and the posterior surface of the contact lens, wherein at least one of the anterior and posterior surface includes a vertical meridian, a horizontal meridian, and a central optical zone,

wherein the central optical zone has a top boundary, a bottom boundary, a distance vision zone and a rotationally-asymmetrical progressive zone adjacent to the distance vision zone;

wherein the distance vision zone is located in the upper portion of the central optical zone and provides a distance power for distance vision correction;

wherein the rotationally-asymmetrical progressive zone is located in the lower portion of the central optical zone and provides a variable intermediate vision correction and near vision corrections; and

wherein the rotationally-asymmetrical progressive zone has a surface that provides a power addition profile, along the upper vertically radiating semi-meridian, which is defined by two or more linear functions of equation (1) or by equation (2) or equation (3)

$\begin{array}{cc}\{\begin{array}{cc}p<br><br>\left(x\right)=b_1+k_1<br><br>x& <br><br>0\le <br><br>x<<br><br>x_1\\ p<br><br>\left(x\right)=b_2+k_2<br><br>x& <br><br>x_1\le <br><br>x<<br><br>x_2\\ \mathrm{⋮<br><br>}& \\ p<br><br>\left(x\right)=b_i+k_i<br><br>x& <br><br>x_{i-1}\le <br><br>x<<br><br>x_i\\ \mathrm{⋮<br><br>}& \end{array}& \left(1\right)\\ p<br><br>\left(x\right)=\frac{A}{2}·<br><br>\cos <br><br>\left(\frac{x}{X_o}<br><br>\mathrm{\pi <br><br>}\right)+\frac{A}{2}& \left(2\right)\\ p<br><br>\left(x\right)=A·<br><br>\left[1-{\left(\frac{x}{X_0}\right)}^n\right]& \left(3\right)\end{array}$

in which p(x) is an added power at a radial distance of x from the radial center;

b_i is a coefficient which is the intercept of a linear line;

k_i is the rate of change of the added power as function of the distance from the radial center;

A is the maximum added power;

X_o is a radial distance between the radial center and the optical axis; and

n is any number which can be an integer or non-integer larger than 1 but smaller than or equal to 10.

29. The method of claim 28, wherein the rotationally-asymmetrical progressive zone has an upper boundary, a lower boundary, a radial center, an upper vertically radiating semi-meridian and a lower vertically radiating semi-meridian, and wherein the rotationally-asymmetrical progressive zone further has a surface that provides a power profile that increases, along the upper vertically radiating semi-meridian, from the distance power at the upper boundary to a near power at the radial center and remains substantially constant from the radial center to a point near the lower boundary along the lower vertically radiating semi-meridian.

30. The method of claim 29, wherein the anterior surface includes the vertical meridian, the horizontal meridian, and the central optical zone having the top boundary, the bottom boundary, the distance vision zone and the rotationally-asymmetrical progressive zone adjacent to the distance vision zone.

31. The method of claim 30, wherein the central optical zone is a circular zone which is concentric with the geometric center of the anterior or posterior surface, or the center of which is deviated from the geometric center of the anterior or posterior surface by up to 2 mm.

32. The method of claim 30, wherein the distance zone extends downwardly from the top boundary of the central optical zone;

wherein the lower boundary line of the distance zone with the rotationally-asymmetrical progressive zone is at or slightly below a horizontal line passing through the center of the central optical zone and parallel with the horizontal meridian, at least in its central portion.

33. The method of claim 32, wherein the apex of the distance vision zone coincides with the center of the central optical zone and wherein the optical axis of the lens passes through the apex of the distance vision zone and the center of the optical zone of the posterior surface.

34. The method of claim 30, wherein the radial center is located below the center of the central optical zone and on the vertical meridian or a line parallel to the vertical meridian and passing through the center of the central optical zone, and wherein the distance between the radial center and the optical axis of the lens, the optical axis passing through the center of the central optical zone, is about 2.0 mm or less.

35. The method of claim 30, wherein the central optical zone is characterized by that the lateral separation between images from the distance vision zone and the rotationally-asymmetrical progressive zone is minimized or eliminated so as to minimize or eliminate ghost images.

36. The method of claim 30, wherein a first line passing through the radial center and the center of curvature at the radial center intersects the optical axis of the lens, wherein the intersection point is within 2 mm or less of the center of curvature at the apex of the posterior surface.

37. The method of claim 30, wherein the rotationally-asymmetrical progressive zone is tangent to the distance vision zone at any point along the upper and lower boundaries of the rotationally-asymmetrical progressive zone.

38. The method of claim 30, wherein the contact lens comprises one or more orientation or stabilization features.

39. The method of claim 38, wherein said one or more orientation/stabilization features are selected from the group consisting of:

a prism ballast or the like that uses a varying thickness profile to control the lens orientation;

a faceted surface in which parts of the lens geometry is removed to control the lens orientation;

a ridge feature which orients the lens by interacting with the eyelid;

double slab-off features which have a top slab-off zone and a bottom slab-off zone zones to maintain the lens orientation on the eye; and

non-prism ballast features in the peripheral zone of the lens, the peripheral zone surrounding the optical zone of the lens.

40. The method of claim 38, wherein the contact lens comprises on the anterior surface of the lens a ramped ridge zone which is disposed below the optical zone and includes an upper boundary, a lower ramped boundary, a latitudinal ridge that extends outwardly from the anterior surface, and a ramp that extends downwardly from the lower ramped boundary and has a curvature or slope that provides a varying degree of interaction between the ramped ridge zone and the lower eyelid of an eye depending on where the lower eyelid strikes the ramped ridge zone.

41. The method of claim 38, wherein the anterior surface comprises a blending zone extending outwardly from the central optical zone, a peripheral zone surrounding the blending zone, and an boundary zone circumscribing and tangent to the peripheral zone,

wherein the blending zone has a surface which ensures that the peripheral zone, the blending zone and the central optical zone are tangent to each other, wherein the peripheral zone has a surface that, in combination with the posterior surface, provides in the peripheral zone of the lens a thickness profile which is characterized (1) by having a lens thickness which increases progressively from the top of the lens downwardly along each of the vertical meridian and lines parallel to the vertical meridian until reaching a maximum value at a position between the anterior optical zone and the boundary zone and then decreases to the boundary of the boundary zone, or (2) by having a mirror symmetry with respect to a plane cutting through the vertical meridian, by having a substantially constant thickness in a region around the horizontal meridian and by having a thickness which decreases progressively from the horizontal meridian to the top or bottom of the contact lens along each of the vertical meridian and lines parallel to the vertical meridian.

42. The method of claim 38, further comprising the steps of producing the ophthalmic lens by a manufacturing means.

43. The method of claim 42, wherein the manufacturing means is a computer-controllable manufacturing device.

44. The method of claim 43, wherein the computer controllable manufacturing device is a numerically controlled lathe.

45. A method for producing contact lens capable of correcting presbyopia, comprising the steps of:

designing the contact lens which comprises an anterior surface and an opposite posterior surface, wherein at least one of the anterior and posterior surface includes a vertical meridian, a horizontal meridian, and a central optical zone, wherein the central optical zone has a top boundary, a bottom boundary, a distance vision zone and a rotationally-asymmetrical progressive zone adjacent to the distance vision zone,

wherein the distance vision zone is located in the upper portion of the central optical zone and provides a distance power for distance vision correction;

wherein the rotationally-asymmetrical progressive zone is located in the lower portion of the central optical zone and provides a variable intermediate vision correction and near vision correction;

wherein the rotationally-asymmetrical progressive zone has an upper boundary, a lower boundary, a radial center, an upper vertically radiating semi-meridian and a lower vertically radiating semi-meridian, and wherein the rotationally-asymmetrical progressive zone further has a surface that provides a power profile that increases, along the upper vertically radiating semi-meridian, from the distance power at the upper boundary to a near power at the radial center and remains substantially constant from the radial center to a point near the lower boundary along the lower vertically radiating semi-meridian,

wherein the anterior surface includes the vertical meridian, the horizontal meridian, and the central optical zone having the top boundary, the bottom boundary, the distance vision zone and the rotationally-asymmetrical progressive zone adjacent to the distance vision zone,

wherein the anterior surface comprises a blending zone extending outwardly from the central optical zone, a peripheral zone surrounding the blending zone, and an boundary zone circumscribing and tangent to the peripheral zone, and

wherein the blending zone has a surface which ensures that the peripheral zone, the blending zone and the central optical zone are tangent to each other, wherein the peripheral zone has a surface that, in combination with the posterior surface, provides in the peripheral zone of the lens a thickness profile which is characterized (1) by having a lens thickness which increases progressively from the top of the lens downwardly along each of the vertical meridian and lines parallel to the vertical meridian until reaching a maximum value at a position between the anterior optical zone and the boundary zone and then decreases to the boundary of the boundary zone, or (2) by having a mirror symmetry with respect to a plane cutting through the vertical meridian, by having a substantially constant thickness in a region around the horizontal meridian and by having a thickness which decreases progressively from the horizontal meridian to the top or bottom of the contact lens along each of the vertical meridian and lines parallel to the vertical meridian.

46. The method of claim 45, wherein the distance zone extends downwardly from the top boundary of the central optical zone;

wherein the lower boundary line of the distance zone with the rotationally-asymmetrical progressive zone is at or slightly below a horizontal line passing through the center of the central optical zone and parallel with the horizontal meridian, at least in its central portion.

47. The method of claim 46, wherein the apex of the distance vision zone coincides with the center of the central optical zone and wherein the optical axis of the tens passes through the apex of the distance vision zone and the center of the optical zone of the posterior surface.

48. The method of claim 45, wherein the radial center is located below the center of the central optical zone and on the vertical meridian, and wherein the distance between the radial center and the optical axis of the lens is about 2.0 mm or less.

49. The method of claim 45, wherein the central optical zone is characterized by that the lateral separation between images from the distance vision zone and the rotationally-asymmetrical progressive zone is minimized or eliminated so as to minimize or eliminate ghost images.

50. The method of claim 49, wherein a first line passing through the radial center and the center of curvature at the radial center intersects the optical axis of the lens, wherein the intersection point is within 2 mm or less of the center of curvature at the apex.

51. The method of claim 45, wherein the rotationally-asymmetrical progressive zone is tangent to the distance vision zone at any point along the upper and lower boundaries of the rotationally-asymmetrical progressive zone.

52. The method of claim 45, wherein the rotationally-asymmetrical progressive zone has a surface that provides a power addition profile, along the vertical meridian, which is defined by two or more linear functions of equation (1) or by equation (2) or (3)

$\begin{array}{c}\{\begin{array}{c}p\end{array}\end{array}$

( x ) = b 1 + k 1 ⁢

x ⁢

0 ≤

x <

x 1 p ⁡

( x ) = b 2 + k 2 ⁢

x ⁢

x 1 ≤

x <

x 2 ⋮

p ⁡

( x ) = b i + k i ⁢

x ⁢

x i - 1 ≤

x <

x i ⋮

( 1 ) p ⁡

( x ) = A 2 ·

cos ⁡

( x X o ⁢

π

) + A 2 ( 2 ) p ⁡

( x ) = A ·

[ 1 - ( x X 0 ) n ] ( 3 )

in which p(x) is an added power at a radial distance of x from the radial center;

b_i is a coefficient which is the intercept of a linear line;

k_i is the rate of change of the added power as function of the distance from the radial center;

A is the maximum added power;

X_o is a radial distance between the radial center and the optical axis; and

n is any number which can be an integer or non-integer larger than 1 but smaller than or equal to 10.

53. The method of claim 45, further comprising the steps of producing the contact lens by a manufacturing means.

54. The method of claim 53, wherein the manufacturing means is a computer-controllable manufacturing device.

55. The method of claim 54, wherein the computer controllable manufacturing device is a numerically controlled lathe.