Contact lenses and related methods

Abstract

A contact lens (201) comprises an optical zone (202) centered on an optical axis (219) and a peripheral zone (204) surrounding the optical zone (202). A cross-sectional slice of the optical zone (202) taken along a meridian includes a series of consecutive circular arcs (203a-h) having a radial curvature-power profile that increases monotonically with radial distance from the optical axis (219). Light rays from a distant point source passing through the midpoint of each arc (203a-h) converge towards a point (215) on the optical axis, and for each arc (203a-h), light rays from a distant point source passing through the arc (203a-h) converge towards a point (216) at a first distance from the optical axis. A method for designing and manufacturing such a contact lens (201) is also described.

Description

[Technical Field]

[0001] The present invention relates to contact lenses. The invention particularly (but not exclusively) relates to contact lenses for slowing the progression of myopia. The invention particularly (but not exclusively) relates to contact lenses for use by presbyopes. The invention also relates to methods of manufacturing such lenses and methods of designing such lenses. [Background technology]

[0002] Many people, both children and adults, need contact lenses to correct myopia (nearsightedness), and many adults may need lenses to correct presbyopia (the inability to focus on nearby objects due to age-related loss of accommodation).

[0003] A myopic eye focuses incident light from distant objects at a location in front of the retina. As a result, light converges toward the plane in front of the retina and diverges toward the retina, reaching the retina out of focus. Conventional lenses for correcting myopia (e.g., eyeglass lenses and contact lenses) reduce the convergence of incident light from distant objects (in the case of contact lenses) or cause the incident light to diverge (in the case of eyeglasses) before it reaches the eye, thereby shifting the focus position onto the retina.

[0004] Presbyopic eyes cannot effectively change shape to accommodate near objects. This prevents people with presbyopia from focusing on near objects. Traditional lenses for correcting presbyopia (e.g., eyeglass lenses and contact lenses) include bifocal and progressive lenses, which include an area optimized for near vision and an area optimized for distance vision. Presbyopia can also be treated using bifocal and multifocal lenses, or monovision lenses (where each eye is provided with a different prescription, such as one eye provided with a lens for distance vision and the other eye provided with a lens for near vision).

[0005] Decades ago, it was proposed that the progression of myopia in children and adolescents could be slowed or prevented by undercorrection, i.e., by bringing the focal point closer to the retina but not completely onto it. However, this approach inevitably resulted in decreased distance vision compared to that achieved with lenses that fully correct myopia. Furthermore, the effectiveness of undercorrection in controlling myopia progression is now considered questionable. A more recent approach to correcting myopia is to provide lenses that have both one or more regions that provide full correction of distance vision and one or more regions that undercorrect, i.e., intentionally induce myopic defocus. It has been suggested that this approach can prevent or slow the onset or progression of myopia in children and adolescents while providing good distance vision. In lenses with regions that provide defocus, the region that provides full correction of distance vision is typically referred to as the base power region, and the region that provides undercorrection or intentionally induces myopic defocus is typically referred to as the myopic defocus region or add power region (where the power is more positive or less negative than the power (diopter) of the distance region).

[0006] The surface of the add-power region (typically the anterior surface) has a smaller radius of curvature than the distance-power region, thus providing a more positive or less negative optical power (diopter) to the eye. The add-power region is designed to focus incoming parallel light (i.e., light from farther away) into the eye in front of the retina (i.e., closer to the lens). The distance-power region is designed to focus light to form an image on the retina (i.e., closer to the lens).

[0007] A known type of contact lens that reduces the progression of myopia is the bifocal contact lens, available under the name MISIGHT (CooperVision, Inc.). Unlike bifocal and multifocal contact lenses designed to improve vision in presbyopic individuals, bifocal lenses are constructed with predetermined optical dimensions that provide the use of distance correction (i.e., base power) to view both distant and near objects. The treatment zone of the bifocal lens, which has an add power, provides myopic defocused images at both distant and near viewing distances.

[0008] While these lenses have been found to be beneficial in preventing or slowing the onset or progression of myopia, the annular add-power region can cause undesirable visual side effects. Light focused by the annular add-power region in front of the retina diverges from its focal point, forming a defocused ring on the retina. Thus, wearers of these lenses may see a ring or "halo" around the image formed on the retina, especially for small, bright objects such as street lamps or car headlights. Furthermore, rather than using the eye's natural accommodation (i.e., the eye's natural ability to change focal length) to focus on nearby objects, the wearer could theoretically utilize the additional focal point in front of the retina resulting from the annular add-power region to focus on nearby objects. This, in turn, could lead to the wearer unconsciously using the lenses in the same manner as presbyopia-correcting lenses, which is undesirable for young subjects.

[0009] It has been recognized that for the treatment of myopia, it may be beneficial to provide a lens that introduces additional myopic defocus. For the treatment of presbyopia, it may be beneficial to provide a lens that extends the depth of focus. The present disclosure aims to provide improved lenses that introduce additional myopic defocus and benefit from the improved image quality made possible by off-axis imaging techniques such as those described above. Summary of the Invention

[0010] According to a first aspect, the present disclosure provides a contact lens comprising an optic zone centered on an optical axis and a peripheral zone surrounding said optic zone, wherein a cross-sectional slice of said optic zone taken along a meridian reveals a series of contiguous multiple peripheral zones having a radial curvature power profile that increases monotonically with radial distance from said optical axis. Curve Each Curve A plurality of light rays from a distant point source passing through the midpoint of the first optical axis converge toward a single point on the first optical axis. Curve Regarding the Curve The light rays passing through converge towards a point at a first distance from the optical axis.

[0011] According to a second aspect, the present disclosure provides a method of manufacturing a lens, the method comprising forming a lens according to the first aspect of the invention.

[0012] According to a third aspect, the present disclosure provides a method for designing a contact lens, the method comprising the steps of modeling a contact lens, the lens including an optic zone centered on an optical axis and a peripheral zone surrounding the optic zone, a cross-sectional slice of the optic zone taken along a meridian having a radial curvature power profile that increases monotonically with radial distance from the optical axis, and a central portion of the optic zone centered on the optical axis. Curve A series of continuous multiple Curve The method further comprises dividing the series of consecutive pluralities of the model into Curve Each in Curve The relevant Curve tilted around the midpoint of each Curve A plurality of light rays from a distant point source passing through the midpoint of the Curve Regarding Curveconverging a plurality of light rays passing through the lens toward a point at a first distance from the optical axis. The method further comprises designing a lens based on the modeled lens.

[0013] Of course, it will be understood that features described in connection with one aspect of the present disclosure may be incorporated in other aspects of the present disclosure, for example, a method of the present disclosure may incorporate features described with reference to an apparatus of the present disclosure, and vice versa.

[0014] Embodiments of the present invention will now be described, by way of example only, with reference to the accompanying schematic drawings. [Brief explanation of the drawings]

[0015]

Figure 1A

[0016]

Figure 1B

[0017]

Figure 2A

[0018]

Figure 2B

[0019]

Figure 2C

[0020]

Figure 3

[0021]

Figure 4A

[0022]

Figure 4B

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Figure 5A

[0024]

Figure 5B

[0025]

Figure 6A

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Figure 6B

[0027]

Figure 6C

[0028]

Figure 6D

[0029] [[ID=2 FIG. 7A is a plot (graph) showing the variation of sagittal power in the radial direction for the lens shown in FIGS. 5A and 5B.

[0030] ​ FIG. 7B is a plot (graph) showing the variation of the radial curvature power of the lens shown in FIGS. 5A and 5B.

[0031] ​ FIG. 8A is a plan view of a lens according to one embodiment of the present disclosure.

[0032] ​ FIG. 8B is a cross-sectional slice through the optical zone of the lens of FIG. 8A along meridian AA.

[0033] ​ FIG. 9 is a partial ray diagram of the lens of FIG. 8A, showing the focal points of multiple rays passing through the central region and multiple concentric annular regions.

[0034] ​ FIG. 10 is a flow chart illustrating a method for designing a contact lens according to one embodiment of the present disclosure.

[0035] ​ FIG. 11A is a schematic plan view of a contact lens modeled in a first step of a method for designing a contact lens according to an embodiment of the present disclosure.

[0036] ​ FIG. 11B is a cross-sectional slice along a meridian view of a contact lens modeled using a method for designing a contact lens according to an embodiment of the present disclosure.

[0037] ​FIG. 11C is a schematic plan view of the final contact lens modeled using a method for designing a contact lens according to an embodiment of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0038] According to a first aspect, the present disclosure provides a contact lens comprising an optic zone centered on an optical axis and a peripheral zone surrounding the optic zone, wherein a cross-sectional slice through the optic zone taken along a meridian defines a series of contiguous multiple peripheral zones having a radial curvature power profile that increases monotonically with radial distance from the optical axis. ​ Each ​ A plurality of light rays from a distant point source passing through the midpoint of the first optical axis converge toward a single point on the first optical axis. ​ Regarding the ​ The light rays passing through converge towards a point at a first distance from the optical axis.

[0039] As used herein, the term contact lens refers to an ophthalmic lens that can be placed on the front of the eye. It will be understood that such contact lenses provide clinically acceptable on-eye movement and do not bond to the human eye. The contact lens can be in the form of a corneal lens (e.g., a lens that rests on the cornea of ​​the eye). The contact lens can be a soft contact lens, such as a hydrogel contact lens or a silicone hydrogel contact lens. The lens can be a lens used to prevent or slow the onset or progression of myopia, or a lens used to provide an extended depth of focus to a myopic eye.

[0040] A contact lens according to the present disclosure comprises an optic zone. The optic zone encompasses a portion of the lens having an optical function. The optic zone is configured to be positioned over the pupil of the eye during use. The optic zone is centered on an optical axis. The optical axis may be along the centerline of the lens. A series of contiguous multiple optic zones extending radially outward from the optical axis along any meridian may be included. ​ In addition, a center with a constant radial curvature power ​ Alternatively, two central lenses with constant radial curvature power may be used. ​ The lens may include a central region centered on the optical axis, and the central portion may extend in opposite directions outward from the optical axis. ​ or multiple centers ​ The central region of the lens may be a central region. ​ or center ​ The distal focal plane is an area spanned by a first optical axis, but allows light from a distant point object to be focused (converged) onto a spot on the first optical axis at the distal focal plane. As used herein, the term plane does not refer to a physical surface, but rather to a plane that can be depicted through the point at which light from a distant object is focused. Such a plane is also called an image plane (which may be curved) or an image shell. The eye focuses light onto a curved retina. In a perfectly focused eye, the curvature of the image shell matches the curvature of the retina. Thus, the eye does not focus light onto a flat mathematical plane. Nevertheless, in the art, the curved surface of the retina is commonly referred to as a (planar) surface.

[0041] In the context of this disclosure, a series of multiple ​ is a series of multiple wires that are connected end to end. ​ In the context of this disclosure, ​ represents a 2D (two-dimensional) slice taken along the meridian of a 3D (three-dimensional) lens. ​ There may be a transition section linking (connecting) a series of multiple ​ Each in ​is centered around the midpoint of its length ​ A series of multiple ​ In the above, the plurality of ​ The curvature of increases monotonically with increasing distance from the optical axis. Therefore, when considering a lens in 3D, the radial curvature of that lens increases monotonically with increasing radial distance from the optical axis.

[0042] All ​ When you think about it, each ​ Light rays from a distant point source passing through the midpoint of converge to a point on the first optical axis, which coincides with the spot formed by light focused along the optical axis.

[0043] A single point along a given meridian ​ Considering this, the single ​ Light rays from a distant point source passing through a single ​ The rays passing through the optical axis are directed to a point (the ​ The first distance is a non-zero distance. ​ The point around the half-length of ​ The distance from the optical axis is the result of the relative tilt of the lens. ​ It will depend on the radial distance of the lens. ​ In this case, ​ The point where multiple light rays passing through converge is far from the center of the lens. ​ will be closer to the optical axis in the radial direction than in the single ​ The rays passing through converge to a point in front of the far focal plane (i.e., closer to the lens).

[0044] The lens is centered on the optical axis and ​ The central region may be substantially circular in shape and may have a diameter of about 2 mm to about 9 mm, preferably 2 to 7 mm. The central region may be substantially oval in shape.

[0045] The optic zone may be surrounded by a peripheral zone, which is not part of the optic zone but is located outside the optic zone and above the iris when the lens is worn, and which serves a mechanical function, such as increasing the size of the lens to make it easier to handle, providing ballast to prevent lens rotation, and / or providing a geometric region that improves comfort for the lens wearer. The peripheral zone may extend to the edge of the contact lens.

[0046] A contact lens according to an embodiment of the present disclosure may include a ballast for orienting the lens when positioned on a wearer's eye. An embodiment of the present disclosure incorporating a ballast into a contact lens rotates to a predetermined angle of repose when placed on the wearer's eye by the action of the wearer's eyelid. For example, the ballast may be a wedge, and rotation may occur through the action of the eyelid on the wedge. Ballasting contact lenses to orient the contact lens is well known in the art. For example, toric contact lenses are ballasted to orient the lens so that the orthogonal cylindrical correction provided by the lens is precisely aligned with the astigmatism of the wearer's eye. Contact lenses of the present disclosure may provide specific benefits to the wearer in a given orientation. For example, a contact lens may provide specific benefits to the wearer when the maximum addition power meridian is in a particular direction.

[0047] The contact lens may be substantially circular in shape and have a diameter of about 4 mm to about 20 mm. The optic zone may be substantially circular in shape and have a diameter of about 2 mm to about 10 mm. In some embodiments, the contact lens has a diameter of 13 mm to 15 mm, and the optic zone has a diameter of 7 mm to 9 mm.

[0048] In the context of this disclosure, the refractive power of the lens at any point in the optical zone may be defined as the radial curvature power, the circumferential curvature power, the mean curvature power (which is the average of the radial curvature power and the circumferential curvature power), the radial sagittal power, the circumferential sagittal power, and the mean sagittal power (which is the average of the radial sagittal power and the circumferential sagittal power).

[0049] The curvature power and sagittal power are defined as follows:

[0050] For a given wavefront W, at a point a radial distance r (pupil radius) from a line perpendicular to the center of the wavefront, W(r) = A*r 2 where A is a function.

[0051] The wavefront curvature, or curvature power Pc, is a function of the second derivative of the wavefront. The wavefront slope, or slope-based power Ps, is a function of the first derivative of the wavefront and varies with the slope (gradient) of the wavefront.

[0052] For a simple spherical lens, the curvature power Pc is defined as follows: JPEG0007781290000001.jpg942 The slope-based refractive power Ps is defined as follows: JPEG0007781290000002.jpg936In other words, in the case of a simple lens assumed to be paraxial (paraaxial), Pc = Ps.

[0053] Radial curvature power is the curvature power in a direction extending radially outward from the center of curvature of the lens. Circumferential curvature power is the curvature power at a constant radial coordinate extending along the circumference of the lens.

[0054] Radial sagittal power is the sagittal power in a direction extending radially outward from the center of the lens. Circumferential sagittal power is the sagittal power at a constant radial coordinate extending along the circumference of the lens.

[0055] A series of consecutive multiple ​ Each in ​ is the ​ The optic zone will have a radial curvature (i.e., curvature along its length) that is proportional to the radial curvature power of the lens along the optic zone. The optic zone may have a curvature power resulting from the curvature of the anterior or posterior surface of the lens. ​ The curvature of the arc can be the curvature of the anterior surface of the lens, or it can be the curvature of the posterior surface of the lens. ​ The radial curvature of the lens along can result from the combination of the curvature of the posterior surface of the lens and the curvature of the anterior surface of the lens.

[0056] For lenses according to some embodiments of the present disclosure, the radial curvature power increases monotonically from the center of the lens radially outward along the meridian, which may increase spherical aberration.

[0057] The increase in radial curvature power may be continuous or may be in a stepwise or discontinuous manner. Thus, a plurality of successive axial curvatures along a given meridian may be increased. ​ The radial curvature power may increase from the center of the lens to the outside, and ​ The radial curvature power can be (relatively) smaller, and the farther away from the center of the lens, the ​ can have a (relatively) larger radial curvature power.

[0058] A series of consecutive multiple ​ Each in ​ may be tilted about a halfway point (midpoint) along its length, ​ The sagittal power of the radial direction is reduced, but the ​The radial curvature power of the lens does not change. ​ Each in ​ As a result of the local gradient of ​ The focus of light passing through this will be shifted from the optical axis.

[0059] A series of consecutive multiple ​ Each in ​ is the ​ Therefore, each ​ The radial curvature power along the length of the lens may be constant.

[0060] Along any meridian, center ​ There may be a center ​ may be centered on the optical axis and have a constant radial curvature and a constant radial curvature power. Alternatively, along any meridian, two central ​ There may be segments that extend radially outward from the optical axis in opposing directions. ​ or center ​ The radial curvature power of the portion may provide the base power of the lens, which may be between +0.5D and -15.0D, preferably between about -0.25D and -15.0D.

[0061] A series of consecutive points along a given meridian ​ any of ​ or all ​ However, ​ Moving outward from the center of the lens, the lens may have a continuous plurality of radial curvatures. ​ The radial curvature and power of each successive lens increases. ​ At the junctions between successive ​ There may be a transition region between successive ​ At each junction between the first and second junctions, a continuous or discontinuous increase in radial curvature power may be provided.

[0062] Along each meridian ​ The radial curvature power provided by may provide an add power, which may be between +0.5D and +20.0D, preferably between +0.5D and +10.0D. ​ The net power along the line can be the sum of the base power and the add power. ​ provides less additional power and is located further from the center of the lens ​ can provide greater add-on power.

[0063] A series of multiple ​ Each in ​ is the ​ Within the lens, the curvature may increase with radial distance from the center of the lens.

[0064] each ​ The radial curvature along the length of the lens may not be constant, but may increase with radial distance from the center of the lens. ​ The radial curvature refractive power along the length of the ​ This may result in a continuous increase in radial curvature power extending radially outward along any given meridian. The increase in radial curvature power extending outward from the optical axis may be a linear increase in radial curvature power. ​ , or two opposite central points extending radially outward from the optical axis along any given meridian. ​ The portion may have a constant radial curvature, which may provide the base power. ​ or center ​ A series of multiple extending radially outward from the portion ​ Other in ​ may have a curvature that increases with increasing radial distance from the center of the lens. ​ or center ​The optic zone (which may span a portion) may have a constant optical power, and the remainder of the optic zone may have an additive optical power that increases as it extends radially outward from the central region.

[0065] A series of consecutive multiple lines along the meridian ​ is a series of symmetrical multiple beams centered on the optical axis. ​ A series of multiple lines along the meridian may be ​ is at least six radially outwardly extending from the optical axis ​ A series of multiple lines along the meridian may be ​ is at least 10 radially outwardly extending from the optical axis ​ A series of consecutive multiples along the meridian may be ​ at least three radially outwardly extending beams on each side of the optical axis; ​ A series of consecutive multiples along the meridian may be ​ at least five radially outwardly extending beams on each side of the optical axis; ​ A series of consecutive multiple ​ Each in ​ may have the same length. Alternatively, a series of multiple ​ Some in ​ However, they may have different lengths.

[0066] All cross-sectional slices taken along all meridians of the optical zone may have substantially the same curvature profile. ​ The circumferential curvature power, and optionally the circumferential sagittal power, of the central region of the lens spanned by each meridian may be constant at a constant radial distance from the center of the lens. ​ The curvature power of the entire central region can be determined by the central ​ may span and be constant.

[0067] Along each meridian, the radial curvature power profile may be the same, in which case the circumferential curvature power around the lens may be constant for a certain radial distance from the center of the lens. Alternatively, along different meridians, the radial curvature power profile may be different from a plurality of ​ When the number and length of ​ The circumferential curvature power profile around the optic zone may vary as the curvature of the lens changes. In this case, the circumferential curvature power profile around the optic zone may vary according to the meridian around the lens. The circumferential curvature power profile around the optic zone may vary periodically or aperiodically. The circumferential curvature power may oscillate between a maximum and a minimum value. The circumferential curvature power profile may oscillate with a sinusoidal, sawtooth, or step-like profile.

[0068] Consider a 3D lens formed by summing 2D cross-sectional slices along each meridian, and a series of multiple ​ may be summed to form a series of concentric annular regions extending outward from a central region. ​ If each of the curvature profiles has substantially the same radial curvature profile, ​ may form circular concentric annular regions extending outward from the center of the lens. ​ If the concentric annular regions are of the same length, then each of the concentric annular regions may have the same width. ​ may have different radial curvature power profiles, which may result in concentric annular regions extending partially around the circumference of the lens, or oval or elliptical annular regions.

[0069] Cross-sectional slices taken along any meridian of the optical zone may have substantially the same sagittal power profile. ​ Each ​ may be tilted about the midpoint of its length, ​Along each meridian, the radial-sagittal power profile may be the same, in which case the circumferential sagittal power around the lens is constant. Alternatively, along different meridians, the radial-sagittal power profile may be different from the multiple meridians of each series. ​ are tilted by different amounts, or multiple ​ The circumferential sagittal power profile around the optical zone may vary when the number and length of the axially extending optics change. In this case, the circumferential sagittal power profile around the optical zone may vary according to the meridian around the lens. The circumferential sagittal power profile around the optical zone may vary periodically or aperiodically. The circumferential sagittal power may oscillate between a maximum and a minimum value. The circumferential sagittal power profile may oscillate with a sinusoidal, sawtooth, or step-like profile.

[0070] Contact lenses may include elastomer materials, silicone elastomer materials, hydrogel materials, or silicone hydrogel materials, or combinations thereof. As understood in the contact lens field, a hydrogel is a material that retains water in equilibrium and does not contain silicone-containing compounds. A silicone hydrogel is a hydrogel that contains silicone-containing compounds. As described in the context of this disclosure, hydrogel and silicone hydrogel materials have an equilibrium water content (EWC) of at least 10% to about 90% (wt / wt). In some embodiments, hydrogel or silicone hydrogel materials have an EWC of about 30% to about 70% (wt / wt). By comparison, as described in the context of this disclosure, silicone elastomer materials have a water content of about 0% to less than 10% (wt / wt). Typically, silicone elastomer materials used in the present methods or devices have a water content of 0.1% to 3% (wt / wt).Examples of suitable lens formulations (compositions) include those having the following United States Adopted Names (USAN): methafilcon A, ocufilcon A, ocufilcon B, ocufilcon C, ocufilcon D, omafilcon A, omafilcon B, comfilcon A, enfilcon A, stenfilcon A, fanfilcon A, etafilcon A, senofilcon A, senofilcon B, senofilcon C, senofilcon D ... Senofilcon A, Senofilcon B, Senofilcon C, Narafilcon A, Narafilcon B, Balafilcon A, Samfilcon A, Lotrafilcon A, Lotrafilcon B, Somofilcon A, Riofilcon A, Delefilcon A, Verofilcon A, Kalifilcon A, and the like.

[0071] Alternatively, the lens may comprise, consist essentially of, or consist of a silicone elastomer material. For example, the lens may comprise, consist essentially of, or consist of a silicone elastomer material having a Shore A hardness of 3 to 50. Shore A hardness may be determined using conventional methods (e.g., using method DIN 53505), as understood by those skilled in the art. Other silicone elastomer materials may be obtained, for example, from NuSil Technology or Dow Chemical Company.

[0072] According to a second aspect, the present disclosure provides a method of manufacturing a contact lens, the method may comprise forming a contact lens including an optic zone centered on an optical axis and a peripheral zone surrounding the optic zone, wherein a cross-sectional slice through the optic zone taken along a meridian defines a series of contiguous multiple peripheral zones extending radially outward from the optical axis. ​ Each ​ A plurality of light rays from a distant point source passing through the midpoint of the first optical axis converge toward a single point on the first optical axis. ​ Regarding the ​ Light rays from a distant point source passing through converge towards a point at a first distance from the optical axis.

[0073] The lens may include any of the features previously described with respect to the first aspect of the present disclosure.

[0074] The manufacturing method may include forming a female member having a concave lens-forming surface and a male member having a convex lens-forming surface. The method may include filling a gap between the female member and the male member with bulk lens material. The method may further include curing the bulk lens material to form a lens.

[0075] Contact lenses can be formed using lathing. Lenses can be formed by a cast molding process, a spin casting process, or a lathing process, or a combination thereof. As understood by those skilled in the art, cast molding refers to the process of forming a lens by placing a lens-forming material between a female mold member having a concave lens-forming surface and a male mold member having a convex lens-forming surface.

[0076] According to a third aspect, the present disclosure provides a method of designing a contact lens, the method comprising the steps of modeling a contact lens, the lens including an optic zone centered on an optical axis and a peripheral zone surrounding the optic zone, a cross-sectional slice of the optic zone taken along a meridian having a radial curvature power profile that increases with radial distance from the optical axis, and a central portion of the optic zone centered on the optical axis, the central portion of the peripheral zone surrounding the optic zone ... ​ A series of continuous multiple ​ The method further comprises dividing the series of consecutive pluralities of the model into ​ Each in ​ The relevant ​ tilted around the midpoint of each ​ A plurality of light rays from a distant point source passing through the midpoint of the ​ Regarding ​ converging a plurality of light rays passing through the lens toward a point at a first distance from the optical axis. The method further comprises designing a lens based on the modeled lens.

[0077] The lens may be designed using modeling, which may be computer-implemented modeling. The designed lens may include any of the features described above.

[0078] FIG. 1A shows a schematic plan view of a contact lens using a therapeutic zone that provides a myopic defocused image to reduce myopia progression. FIG. 1B shows a schematic side view of the contact lens of FIG. 1A. Lens 1 includes an optical zone 2, which generally covers the pupil, and a peripheral zone 4, which is located above the iris. Peripheral zone 4 provides mechanical functions, including increasing the size of the lens to make it easier to handle, providing ballast to prevent rotation of lens 1, and providing a geometric region that improves comfort for the wearer of lens 1. Optical zone 2 provides the optical function of lens 1 and includes an annular region 3 and a central region 5. Lens 1 has a base radial curvature power, which is equal to the base radial sagittal power. The base power results from the radii of curvature of the surfaces of lens 1. The center of curvature of central zone 5 lies on first optical axis 19 (shown in FIG. 2A). The annular region 3 has a radial curvature refractive power greater than that of the base. The radial curvature refractive power of the annular region 3 is provided by a radius of curvature 6 of the annular region 3, which is smaller than a radius of curvature 7 of the central region 5, as shown in FIG. 3 . The center of curvature of the annular region 3 is on a first optical axis 19. The annular region 3 has a greater refractive power than the central region 5. As shown in FIG. 2A , the focal point 11 of the annular region 3 and the focal point 15 of the central region 5 share a common optical axis 19. The focal point 11 of the annular region 3 is on a near focal plane 13, and the focal point of the central region 5 is on a distal focal plane 17, which is further away from the posterior surface of the lens. As shown in FIG. 2C , for a point source at infinity, light rays focused by the central region 5 form a focused image 23 at the distal focal plane 17. The light rays focused by the central region 5 also produce an unfocused (out of focus) blur spot 27 in the near focal plane 13 .

[0079] 2B, the light rays focused by the annular region 3 form a focused image 21 at the proximal focal plane 13. The light rays focused by the annular region 3 diverge after the proximal focal plane 13, and the diverging light rays produce a defocused (unfocused) annular (ring-shaped) image 25 at the distal focal plane 17. As previously mentioned, the defocused annular image 25 can result in the wearer of the lens 1 seeing a "halo" around the focused distance image.

[0080] Figure 4A is a plot 31 showing the variation of sagittal power in the radial direction for lens 1 shown in Figures 1A and 1B, and Figure 4B is a plot 33 showing the variation of curvature power in the radial direction for lens 1 shown in Figures 1A and 1B. Figures 4A and 4B show the variation of power along the radial diameter of lens 1. For this lens 1, because annular region 3 has a greater power than central region 5 and because annular region 3 has an on-axis center of curvature, the sagittal power in the radial direction (shown by curve 35) is greater over annular region 3 than over central region 5. The curvature power in the radial direction (shown by curve 37) is also greater over annular region 3 than over central region 5.

[0081] FIG. 5A shows a schematic plan view of a contact lens 101 with non-coaxial optics for reducing myopia progression. The lens 101 has an off-axis center of curvature and does not form an on-axis image at the near focal plane. FIG. 5B shows a schematic side view of the lens of FIG. 5A. Similar to the lens 1 of FIGS. 1A and 1B, the lens 101 includes an optical zone 102 that generally covers the pupil and a peripheral zone 104 that is located above the iris. The peripheral zone 104 provides mechanical functions, including increasing the size of the lens to make it more manageable, providing ballast to prevent rotation of the lens 101, and providing a geometric region that improves comfort for the wearer of the lens 101. The optic zone 102 provides the optical function of the lens 101 and includes an annular region 103 and a central region 105. The lens 101 has a base radial curvature power that is equal to the base radial sagittal power. The base power results from the radii of curvature of the surface of the lens 101. The center of curvature of the central region 105 lies on the first optical axis 119 (shown in FIG. 6A ). The annular region 103 has a radial curvature power that is greater than the base radial curvature power. The radial curvature power of the annular region 103 is provided by the radius of curvature of the annular region 103, which is smaller than the radius of curvature of the central region 105. However, in contrast to lens 1 of FIG. 1A, in lens 101 shown in FIGS. 5A and 5B, the curvature of annular region 103 cannot be defined by a single spherical surface, and the center of curvature of annular region 103 does not lie on first optical axis 119. This is shown in FIG. 6D. Annular region 103 is tilted relative to central region 105, with the outer edge of annular region 103 being higher relative to its inner edge than in lens 1 of FIGS. 1A and 1B (see FIG. 5B). This changes the radial sagittal refractive power of annular region 103, but does not change the radial curvature refractive power of annular region 103. As shown in FIG. 6D, the annular front surface of central region 105 defines a portion of the surface of a sphere 107 of larger radius. The annular front surface of annular region 103 defines a curved annular surface 106 having a smaller radius.

[0082] At the distal focal plane 117, the light rays passing through the central region 105 are focused (converged). The annular region 103 acts as an optical beam stop, which results in a small spot size 124 of light at the distal focal plane 117, as shown in FIG. 6C.

[0083] No single image is formed at the near focal plane 113. As shown in FIG. 6B , at the near focal plane 113, for a point source at infinity, light rays passing through the central region 105 produce a blur circle 128, similar to the lenses of FIGS. 1A-2B . On the other hand, light rays from a distant point source passing through the annular region 103 produce a focused ring 122, which surrounds the blur circle 128, as shown in FIG. 6B . FIG. 6B illustrates the light pattern produced for a distant point source. In contrast to lens 1 of FIGS. 1A and 1B , lens 101 of FIGS. 5A and 5B does not produce a single image or an on-axis image at the near focal plane 113, which could be used to avoid the need for the eye to adapt to near objects. For an extended object at a distance, the focused image formed at the near focal plane 113 is the convolution of (i) the focused image of the extended object that would be obtained with a conventional lens having the refractive power of the annular region 103 and (ii) an optical transfer function that represents the optical effect of the annular region 103.

[0084] In contrast to the lenses of FIGS. 1A and 1B, no annular or "halo" effect occurs at the distal focal plane 117.

[0085] Figure 7A is a plot 131 showing the radial sagittal power variation for the lens 101 shown in Figures 5A and 5B. Figure 7B is a plot 133 showing the radial curvature power variation for the lens 101 shown in Figures 5A and 5B. Figures 7A and 7B show the power variation along the radial diameter of the lens 101. For this lens 101, the annular region 103 has a higher power than the central region 105, which means that the radial curvature power (shown by curve 137) is greater across the annular region 103 than across the central region 105. However, the annular region 103 is tilted relative to the central region 105, so that the annular region 103 has an off-axis center of curvature. The tilt of the annular region 103 relative to the central region 105 means that at the boundary between the central region 105 and the annular region 103, the radial sagittal power is more negative than the radial sagittal power of the central region 105, as shown by curve 135. The radial sagittal power may increase with increasing radial distance towards the outer edge of the annular region 103.

[0086] FIG. 8A is a schematic plan view of a contact lens 201 according to one embodiment of the present disclosure. Similar to lens 1 of FIGS. 1A and 1B and lens 101 of FIGS. 5A and 5B, lens 201 includes an optic zone 202 that generally covers the pupil and a peripheral zone 204 that is located above the iris. Peripheral zone 204 provides mechanical functions, including increasing the size of lens 201 to make it more manageable, providing ballast to prevent rotation of lens 201, and providing a geometric region that improves comfort for the wearer of lens 201. Optical zone 202 provides the optical function of lens 201. Optical zone 202 includes a central region 205 and a series of concentric annular regions 203′, 203″, 203′′, and 203′″.

[0087] 8B shows a cross-sectional slice of the optic zone 202 of the lens 201 shown in FIG. 8A taken along line AA. In 2D (two dimensions), the cross-sectional slice of the optic zone 202 spans the central region 205. ​Showing 205a. Center ​ 205a has a radial curvature profile that provides a base radial curvature power. ​ 205a. A series of continuous plural ​ 203a to 203h extend symmetrically from the central region 205 outward in the radial direction. ​ 203a-203h have a constant radial curvature profile along their length, but have a continuous plurality of ​ The radial curvature of ​ 205a and outwards, so that the innermost ​ 203a and 203e are the outermost ​ The radial curvature power of the optic zone 202 increases from the central region 205 of the lens 201 outward. ​ A stepwise increase is observed at the junction between 203a and 203h.

[0088] each ​ 203a-203h are inclined about the half-length point; ​ For 203a, the point is marked with a symbol X. ​ 230a~203h tilting around its midpoint, ​ 203a-203h, but reduces the radial and sagittal refractive power along the length of ​ The radial curvature power along the length of 203a to 203h is not changed.

[0089] For the lens shown in Figure 8A, cross-sectional slices taken along any meridian produce the same curvature profile. Thus, when considering the optical zone 202 in 3D, the optical zone 202 has a central ​ 205a; and a plurality of continuous ribs extending radially outward from the central region 205. ​8A and 8B, each lens is made up of a series of concentric annular regions 203', 203", 203"', and 203"" formed from 203a to 203h. ​ Concentric annular regions 203', 203", 203'" and 203"" are circular and have substantially the same radial width.

[0090] FIG. 9 shows a partial ray diagram of the lens 201 of FIGS. 8A and 8B. ​ 205a) converge towards a spot 215 on the optical axis 219 in the distal focal plane 217. ​ The multiple rays (dashed lines) passing through the midpoints of 203a-203h also converge towards the same spot 215 on the optical axis 219 in the distal focal plane 217. ​ In the case of 203e, the distance from a distant point light source to the target ​ The rays (dashed lines) passing through converge towards a point 216 at a first distance (designated Y) from the optical axis 219 in a focal plane that is anterior (i.e., closer to the lens) than the distal focal plane 217.

[0091] 10 illustrates a method 501 for designing a contact lens, the lens being a lens according to one embodiment of the present disclosure. In a first step 503, the method includes modeling the contact lens. The lens includes an optic zone centered on the optical axis and a peripheral zone surrounding the optic zone. A cross-sectional slice of the optic zone taken along a meridian has a radial curvature power profile that increases with radial distance from the optical axis. In a second step 505, the method includes modeling the optic zone by dividing the cross-sectional slice into a central portion centered on the optical axis. ​ A series of continuous pluralities extending radially outward from ​ In a third step 507, the method divides the model into a series of contiguous multiple ​ Each in ​ The relevant ​tilting about the midpoint of each ​ A plurality of light rays from a distant point light source passing through the midpoint of the ​ Regarding ​ causing a plurality of light rays passing through the optical axis to converge toward a point at a first distance from the optical axis.

[0092] 11A-11C show an example of a lens 601 modeled using the method 501 described in FIG. 10. In a first step 503, the lens 601 shown in FIG. 11A is modeled. The lens 601 includes an optical zone 602 centered on an optical axis 619 and a peripheral zone 604 surrounding the optical zone 602. The optical zone 602 has a central region 605 centered on the optical axis. Light from a distant point source passing through the central region 605 converges toward a point 615 on the optical axis at a distal focal plane 617. FIG. 11B shows a cross-sectional slice of the optical zone 602 taken along a meridian, with the dashed curve 701 indicating the radial curvature profile of the lens 601 modeled in the first step 503. The central ​ 705a spans the central region 605 of the lens. The radial curvature power profile of the lens 601 increases with radial distance from the optical axis 619. In a second step 505, cross-sectional slices of the lens 601 are represented in the model as a series of contiguous multiple ​ and in a third step 507, the series of consecutive multiple ​ Each in ​ However, ​ This produces the red curve 801 shown in Figure 11B. This curve is based on the center of the lens modeled in the first step. ​ Center unchanged from 705a ​ 805a and a series of consecutive multiple inclinations ​ 805a to 805h. ​ Even if you tilt 805a to 805h, the ​ The curvature refractive power of the radial direction of 805a to 805h does not change. ​Light rays (shown as dashed lines) from a distant point source passing through the midpoints of 805a-805h converge towards a point on the optical axis 619 of the far focal plane 617. ​ When you tilt 805a to 805h, ​ The sagittal power of 805a to 805h in the radial direction is reduced, so each ​ Regarding 805a to 805h, ​ 11B. Light rays (shown as dotted lines) passing through converge toward a point 816 at a first distance (designated H) from the optical axis 619. FIG. 11C shows a schematic plan view of a lens 901 designed based on the dotted line curve 801. The lens 901 has an optical zone 902 that generally covers the pupil and a peripheral zone 904 that sits above the iris. The optical zone 902 provides the optical function of the lens 901. The optical zone 902 has a central region 905 and a series of concentric annular regions 903', 903", 903'" and 903"" that have the radial curvature of the curve 801 shown in FIG. 11B.

[0093] Those skilled in the art will appreciate that features of these exemplary embodiments may be combined in other embodiments within the scope of the present disclosure.

[0094] Where the foregoing description refers to integers or elements that have known, obvious, or foreseeable equivalents, such equivalents are hereby incorporated by reference as if individually set forth herein. Reference should be made to the claims to determine the true scope of the present disclosure. The claims should be construed to embrace all such equivalents. The reader will also understand that any integers or features of the present disclosure described as advantageous, convenient, or the like are optional and do not limit the scope of the independent claims. Furthermore, it should be understood that such optional integers or features may be beneficial in some embodiments of the present disclosure, but may be undesirable in other embodiments and, therefore, may not be present in other embodiments.

Claims

1. A contact lens, an optical zone centered on the optical axis; a peripheral zone surrounding the optical zone; Equipped with a cross-sectional slice of the optical zone taken along a meridian includes a series of continuous curves having a radial curvature power profile that increases monotonically with radial distance from the optical axis; a plurality of light rays from a distant point source passing through the midpoint of each curve converge toward a first point on the optical axis; For each curve, a plurality of light rays from the distant point source passing through the curve converge toward respective second points each at a first distance from the optical axis. A contact lens characterized by:

2. The series of continuous curves are joined end to end.

2. The contact lens of claim 1.

3. Each curve in the series of consecutive curves has a constant curvature within the curve.

3. The contact lens according to claim 1 or 2.

4. Each curve in the series of consecutive curves has a curvature that increases with radial distance from the center of the lens within the curve.

3. The contact lens according to claim 1 or 2.

5. The series of continuous curves is a series of symmetric curves centered on the optical axis.

3. The contact lens according to claim 1 or 2.

6. The series of consecutive curves includes at least six curves.

3. The contact lens according to claim 1 or 2.

7. The series of consecutive curves includes at least 10 curves.

3. The contact lens according to claim 1 or 2.

8. cross-sectional slices taken along any meridian of said optical zone have the same radial curvature power profile; 3. The contact lens according to claim 1 or 2.

9. cross-sectional slices taken along any meridian of said optical zone have the same radial and sagittal power profile; 3. The contact lens according to claim 1 or 2.

10. The circumferential curvature power profile of the optical zone varies with the meridian around the lens.

3. The contact lens according to claim 1 or 2.

11. The sagittal power profile of the optical zone varies with the meridian around the lens.

3. The contact lens according to claim 1 or 2.

12. At the center of the optical zone, the lens has a base power between -0.25D and -15.0D.

3. The contact lens according to claim 1 or 2.

13. The series of consecutive curves has curvatures that provide add power between +0.5D and +20.0D.

3. The contact lens according to claim 1 or 2.

14. The optic zone has a curvature power resulting from the curvature of the anterior and / or posterior surfaces of the lens.

3. The contact lens according to claim 1 or 2.

15. The lens comprises an elastomeric material, a silicone elastomeric material, a hydrogel material, or a silicone hydrogel material, or a mixture thereof.

3. The contact lens according to claim 1 or 2.

16. A method for manufacturing a contact lens, comprising: A process for forming the contact lens according to claim 1 or 2. A method comprising:

17. 1. A method for designing a contact lens, comprising: The process of modeling contact lenses Equipped with The lens is an optical zone centered on the optical axis; a peripheral zone surrounding the optical zone; Including, a cross-sectional slice of the optical zone taken along a meridian has a radial curvature power profile that increases monotonically with radial distance from the optical axis; The method further comprises: dividing, within the model, the cross-sectional slice of the optical zone into a series of contiguous curves beginning with a central curve centered on the optical axis and radiating radially outward; tilting each curve in the series of consecutive curves within the model about its midpoint so that light rays from a distant point source passing through the midpoint of each curve converge toward a first point on the optical axis, while light rays from the distant point source passing through each curve converge toward a respective second point at a first distance from the optical axis; designing a lens based on the modeled lens; A method comprising:

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