Ophthalmic lens having extended depth of focus

Abstract

To provide an ophthalmic lens having an extended depth of focus.SOLUTION: In certain embodiments, an ophthalmic lens (100) includes an optic (102) having an anterior surface (14), a posterior surface (106), and an optical axis (108). At least one of the anterior surface and the posterior surface includes a first zone (112) extending from the optical axis to a first radial boundary, and a second zone (114) extending from the first radial boundary to the edge of the optic. The first zone includes an inner region (116) and an outer region (118) separated by a phase shift feature (120), the phase shift comprising a ridge extending outwardly from the inner region and the outer region.SELECTED DRAWING: Figure 1A

Description

[Technical field]

[0001] FIELD OF THE DISCLOSURE The present disclosure relates generally to ophthalmic lenses, and more particularly, to ophthalmic lenses having a wide range of depth of focus. [Background technology]

[0002] Intraocular lenses (IOLs) are routinely implanted in patients' eyes to replace the natural crystalline lens during cataract surgery. The refractive power of the natural crystalline lens can change under the influence of the ciliary muscle to provide accommodation for viewing objects at different distances from the eye. However, many IOLs provide a single focal power with no provision for accommodation. Multifocal IOLs are also known that provide distance as well as near power (e.g., by using diffractive structures), thereby providing some degree of pseudoaccommodation. However, there remains a need for improved IOLs that can provide pseudoaccommodative power. Summary of the Invention [Means for solving the problem]

[0003] The present disclosure generally relates to an ophthalmic lens (e.g., an IOL) that (1) controls multiple phase shift changes in a pupil region to increase depth of focus, and (2) provides power adjustment in a central sub-region of the pupil region to shift the through-focus curve and rebalance the energy between intermediate and distance corrections. In some embodiments, the ophthalmic lens includes an optical element having an anterior surface, a posterior surface, and an optical axis. At least one of the anterior surface and the posterior surface includes a first zone extending from the optical axis to a first radial boundary and a second zone extending from the first radial boundary to an edge of the optical element. The first zone includes an inner region and an outer region separated by a phase shift feature, the phase shift including a ridge extending outward from the inner region and the outer region.

[0004] For a more complete understanding of the present disclosure, and the advantages thereof, reference is now made to the following description taken in conjunction with the accompanying drawings, in which like reference characters indicate similar features and in which: [Brief description of the drawings]

[0005] [Figure 1A] 1 shows and illustrates embodiments of intraocular lenses having a wide range of focal depths, according to some embodiments of the present disclosure. [Figure 1B] 1 shows and illustrates embodiments of intraocular lenses having a wide range of focal depths, according to some embodiments of the present disclosure. [Diagram 2] 1 shows a plot of surface sag versus radial distance from the optical axis for an example optical element having inner and outer zones with the same base curvature, in accordance with some embodiments of the present disclosure. [Diagram 3] 3 shows a through-focus plot for the surface profile of the optical element shown in FIG. 2 compared to a through-focus plot for a standard aspheric optical element, according to some embodiments of the present disclosure. [Figure 4] 1 shows a plot of surface sag versus radial distance from the optical axis for an example optical element having inner and outer zones with different base curvatures, in accordance with some embodiments of the present disclosure. [Diagram 5] 5 shows a through-focus plot for the surface profile of the optical element shown in FIG. 4 compared to the through-focus plot for the optical element shown in FIG. 2 according to some embodiments of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0006] Those skilled in the art will appreciate that the drawings described below are for illustrative purposes only and are not intended to limit the scope of Applicant's disclosure in any way.

[0007] The present disclosure generally relates to ophthalmic lenses (such as IOLs) having a surface profile that controls the variation in phase shift of light waves passing through various regions of the lens to extend the depth of focus. In the following description, lens features that provide a wide range of depth of focus are described in the context of intraocular lenses (IOLs). However, the present disclosure contemplates that the features may also be applied to other ophthalmic lenses, such as contact lenses. In this specification, the term intraocular lens (and its abbreviation IOL) is used to describe a lens that is implanted inside the eye, either to replace the eye's natural crystalline lens or to otherwise enhance vision, regardless of whether the natural crystalline lens is removed.

[0008] 1A-1B show and illustrate an embodiment of an intraocular lens 100 having a wide range of focal depths, according to some embodiments of the present disclosure. The IOL 100 includes an optic 102 having an anterior surface 104 and a posterior surface 106 disposed about an optical axis OA 108. The IOL 100 may further include a number of haptics 110 operable to position and stabilize the IOL 100, typically within the capsular bag of a patient's eye.

[0009] 1A, the front surface 104 of the optical element 102 includes a first zone 112 extending from the optical axis 108 to a first radial boundary and a second zone 114 extending from the first radial boundary to an edge of the optical element 102. Further, the first zone 112 may include an inner region 116 and an outer region 118 separated by a phase shift feature 120. In general, the above-mentioned surface features of the optical element 102 may result in different amounts of phase shift of light waves passing through the optical element 102 (depending on the region of the optical element 102 through which the light waves pass), and constructive interference between light waves having different amounts of phase shift may result in a wide range of depths of focus. Although the above-mentioned first and second zones 112, 114 are illustrated and described as being disposed on the front surface 104 of the optical element 102, in addition or alternatively, the present disclosure contemplates that the first and second zones 112, 114 may be disposed on the rear surface 106 of the optical element 102.

[0010] In some embodiments, the phase-shifting features 120 may include ridges that project forward from the front surface 104 of the optical element 102. As a result, moving radially outward from the optical axis 108, the phase-shifting features 120 may produce two phase-shift steps. For example, the surface profile of the first zone may be expressed as the following formula: Z first zone =Z base +Z 2ps Formula (1) is defined as follows:

[0011] In equation (1), Z base is the following formula:

number

[0012] In some embodiments, Z base The formula defining Z can contain only quadratic, quartic, and sextic coefficients. In other words, Z base is the following formula:

number

[0013] Although equations (2) and (3) generally define aspheric profiles, the present disclosure contemplates that the constants included in those equations may be selected such that they define spherical profiles. In other words, the first zone (Z base) can be either spherical or aspherical.

[0014] In equation (1), Z 2ps is the base sag profile (Z base ) and may, in part, define the characteristics of the phase shift region 120. For example, Z 2ps is the following formula:

number

[0015] The overall surface profile of optical element 102 as defined by equations (1)-(4) can be represented graphically as a plot of sag versus radial distance from optical axis 108 as shown in FIG. 2. In the plot of FIG. 2, the sag value is base The plotted sag values ​​have been normalized by removing the contribution of Z 2ps 2, the sag profile is a constant for the first zone 112 and the second zone 114. In other words, it is assumed that equation (1) defines the surface profile of the entire optical element 102, as opposed to only the first zone 112 (i.e., Z 2ps is constant from r5 to the radius of the entire optical element 102.

[0016] FIG. 3 illustrates a standard aspheric optical element (i.e., as represented by formula (4)(Z 2ps ) without adding equation (3)(Z base 3 shows a through-focus plot for the surface profile of the optical element shown in FIG. 2 compared to a through-focus plot for an optical element having a surface profile defined only by (Z 2ps The phase-shifting feature 120 represented by (including phase-shifting feature 120 represented by (120)) produces a wider range of focal depth compared to a standard aspheric lens.

[0017] In some embodiments, the base sag profile may be different for the first zone 112 and the second zone 114. For example, the surface profile of the optical element 102 may be determined according to the following formula: Z optic =Z base +Z 2ps Formula (5)

number

[0018] Although the base profiles defined in equation (6) above include only second-, fourth-, and sixth-order coefficients, the present disclosure contemplates that those base profiles may instead be defined to include any suitable number of higher order coefficients (as in equation (1)).

[0019] Because the first zone 112 and the second zone 114 include different base sag profiles, Δ3 (as defined in equation (8)) may provide a smooth transition between the first zone 112 and the second zone 114. For example, the first zone 112 may be modified with a different base curvature (c), conic constant (k), and / or higher order coefficients (a2, a4, a6) compared to the second zone 114 to shift the through-focus curve in the near vision direction compared to the through-focus curve shown in FIG. 3. FIG. 4 shows a plot of surface sag versus radial distance from the optical axis for an optical element 102 having a surface profile defined by equations (5)-(8) according to some embodiments of the present disclosure. The surface profile plotted in FIG. 4 assumes the following values:

[0020] [Table 1]

[0021] The values ​​shown in Table 1 are provided for illustrative purposes only, and the present disclosure contemplates that each of the values ​​may have different ranges of values. By way of example, the present disclosure contemplates that r1 may range from 0.3 mm to 0.7 mm, r4 may range from 0.8 mm to 1.2 mm, the distance between r1 and r2 may range from 0 mm to 0.2 mm, and the distance between r3 and r4 may range from 0 mm to 0.2 mm. As a further example, the present disclosure contemplates that Δ1 may range from -1.5 μm to -0.5 μm, and Δ2 may range from 0.3 μm to 0.9 μm.

[0022] Figure 5 shows a through-focus plot for the surface profile of the optical element shown in Figure 4 compared to the through-focus plot for the optical element shown in Figure 2, according to some embodiments of the present disclosure. As discussed above, modifying the first zone 112 with a different base curvature, conic constant, and / or higher order coefficients (1) rebalances the energy between the intermediate and distance corrections, and (2) shifts the through-focus curve in the myopic direction (near target direction) compared to the through-focus curve for an optical element in which the first zone 112 and the second zone 114 have the same base curvature.

[0023] A variety of techniques and materials may be used to fabricate the IOL 100 described above. For example, the optic 102 of the IOL 100 may be formed of a variety of biocompatible polymeric materials. Some suitable biocompatible materials include, but are not limited to, soft acrylic polymers, hydrogels, polymethymethacrylate, polysulfone, polystyrene, cellulose, acetate butyrate, or other biocompatible materials. By way of example, in one embodiment, the optic 102 may be formed of a soft acrylic polymer commonly known as Acrysof (a cross-linked copolymer of 2-phenylethyl acrylate and 2-phenylethyl methacrylate). The haptics 104 of the IOL 100 may also be formed of suitable biocompatible materials, such as those described above. In some cases, the optic 102 and haptics 104 of the IOL may be fabricated as an integral unit, while in other cases, they may be formed separately and bonded together using techniques known in the art.

[0024] It will be recognized that various of the above-disclosed and other features and functions, or alternatives thereof, may be desirably combined into many other different systems or applications. It will also be recognized that various presently unforeseen or unanticipated alternatives, modifications, variations, or improvements may occur to those skilled in the art, and that such alternatives, variations, and improvements are also intended to be included within the scope of the following claims.

Claims

1. 1. An optical element comprising an optical axis and an optical profile extending radially from the optical axis, the optical profile comprising: a first zone extending from the optical axis to a first radial boundary, the first zone including an inner region and an outer region having a first curvature; a second zone extending from the first radial boundary toward an edge of the optical element; a phase shifting feature including a first phase shifting step, a second phase shifting step, and a ridge of increased thickness extending from the first phase shifting step to the second phase shifting step; Optical element comprising: An ophthalmic lens comprising:

2. The ophthalmic lens of claim 1 , wherein the phase-shifting feature is located inside the first zone and separates the inner region and the outer region.

3. The ophthalmic lens of claim 1 , wherein the first phase-shifting step has a first height and the second phase-shifting step has a second height that is not the same as the first height.

4. The ophthalmic lens of claim 3 , wherein the first height is greater than the second height.

5. The ophthalmic lens of claim 1 , wherein the inner region and the outer region have the same radius of curvature.

6. The ophthalmic lens of claim 1 , wherein the first curvature comprises a first aspheric profile and the second zone has a second curvature comprising a second aspheric profile different from the first aspheric profile.

7. The optical profile of the first zone is defined by the following formula: Z ｆｉｒｓｔ ｚｏｎｅ =Z ｂａｓｅ +Z ２ｐｓ is defined by Z ｂａｓｅ is the following formula: [0010] where r is the radial distance from the optical axis, c is the base curvature of the first zone; k is the conic constant, a ２ , a ４ , and a ６ are the second, fourth, and sixth order coefficients, respectively; Z ２ｐｓ is expressed by the following formula: [0025] is defined by r ０ is the optical axis, The inner region is located at a distance r from the optical axis. １ It has spread to The phase shift feature is r １ From ４ It has spread to The outer region of the first zone has a diameter of r ４ From ５ It has spread to Δ １ is the step height of the phase-shifting feature relative to the inner region; Δ ２ is the step height of the phase shift feature relative to the outer region; 2. The ophthalmic lens of claim 1.

8. The optical profile of the second zone is Z ２ｐｓ is constant in the second zone, and Z ｓｅｃｏｎｄ ｚｏｎｅ At the boundary point between the first zone and the second zone, ｆｉｒｓｔ ｚｏｎｅ When the formula is the same as Z ｓｅｃｏｎｄ ｚｏｎｅ =Z ｂａｓｅ +(Δ １ +Δ ２ ) 8. The ophthalmic lens of claim 7, defined by:

9. The optical profile of the optical element may be expressed by the following formula: Z ｏｐｔｉｃ =Z ｂａｓｅ +Z ２ｐｓ is defined by Z ｂａｓｅ and Z ２ｐｓ is the following formula: [0030] [0045] where r is the radial distance from the optical axis, r ０ is the optical axis, The first zone is located at a distance r from the optical axis. ５ where the inner region extends from the optical axis to １ and the phase shift feature extends to r １ From ４ and the outer region extends to r ４ From ５ It has spread to The second zone is r ５ From ６ It has spread to c is the base curvature of the first zone; k is the conic constant of the first zone; a ２ , a ４ , and a ６ are the second, fourth, and sixth order coefficients of the first zone, respectively; c′ is the base curvature of the second zone; k′ is the conic constant of the second zone; a ２ ', a ４ ', and a ６ ' are the second, fourth and sixth order coefficients of the second zone, respectively; Δ １ is the step height of the phase-shifting feature relative to the inner region; Δ ２ is the step height of the phase shift feature relative to the outer region; Δ ３ is the following formula, [0050] The ophthalmic lens of claim 1 , defined by:

10. Below c≠c', k≠k', a ２ ≠ a ２ ', a ４ ≠ a ４ ', and a ６ ≠ a ６ ' is true, and Δ ３ 10. The ophthalmic lens of claim 9, wherein x is a constant added to the base curvature of the second zone to ensure continuity between the first zone and the second zone.

11. The ophthalmic lens of claim 1 , wherein the ophthalmic lens comprises an intraocular lens.

12. The ophthalmic lens of claim 1 , wherein the ophthalmic lens comprises a contact lens.

13. an optical element including an optical axis and an optical profile extending radially from the optical axis; a phase shifting feature separating an inner region and an outer region of the optical profile, a first phase shift step extending outward from the outer region of the optical profile, the first phase shift step having a first step height; a second phase shift step extending inwardly from the inner region of the optical profile, the second phase shift step having a second step height; a ridge surface of increased thickness extending from the first phase-shifting step to the second phase-shifting step; Including, An ophthalmic lens, wherein the second step height is greater than the first step height such that the inner region is recessed relative to the outer region.

14. The ophthalmic lens of claim 13 , wherein the inner region and the outer region have the same radius of curvature.

15. The ophthalmic lens of claim 13 , wherein the ophthalmic lens comprises an intraocular lens.

16. The ophthalmic lens of claim 13 , wherein the ophthalmic lens comprises a contact lens.

17. 1. An ophthalmic lens having an optical axis, the ophthalmic lens comprising a lens component comprising: a first zone extending from the optical axis to a first radial boundary, the first zone including an inner region and an outer region; a second zone extending from the first radial boundary toward an edge of the optical element; Including, The surface profile of the first zone is defined by the following formula: Z ｆｉｒｓｔ ｚｏｎｅ =Z ｂａｓｅ +Z ２ｐｓ is defined by Z ｂａｓｅ is the following formula: [006] where r is the radial distance from the optical axis, c is the base curvature of the first zone; k is the conic constant, a ２ , a ４ , and a ６ are the second, fourth, and sixth order coefficients, respectively; Z ２ｐｓ is expressed by the following formula: [0070] is defined by r ０ is the optical axis, The inner region is located at a distance r from the optical axis. １ It has spread to The phase shift feature is r １ From ４ It has spread to The outer region of the first zone has a diameter of r ４ From ５ It has spread to Δ １ is the step height of the phase-shifting feature relative to the inner region; Δ ２ is the step height of the phase shift feature relative to the outer region; Eye lenses.

18. The surface profile of the second zone is Z ２ｐｓ is constant in the second zone, and Z ｓｅｃｏｎｄ ｚｏｎｅ At the boundary point between the first zone and the second zone, ｆｉｒｓｔ ｚｏｎｅ When the formula is the same as Z ｓｅｃｏｎｄ ｚｏｎｅ =Z ｂａｓｅ +(Δ １ +Δ ２ ) 18. The ophthalmic lens of claim 17 defined by:

19. The ophthalmic lens of claim 17 , wherein the ophthalmic lens comprises an intraocular lens.

20. The ophthalmic lens of claim 17 , wherein the ophthalmic lens comprises a contact lens.

Images