Ophthalmic lenses and related methods

Abstract

An ophthalmic lens (101), a method of manufacturing such a lens (101) and a method of designing such a lens (101) are described. The lens (101) comprises an optical zone (103) centered on an optical axis (102) and a peripheral zone (105) surrounding the optical zone (103). Within the optical zone (103), along a first meridian (107a), the lens (101) has a first radial diopter measurement curve that varies continuously in a first radial direction from the optical axis (102) to the peripheral zone (105). Along a second different meridian (107b), the lens has a second different radial curvature diopter measurement curve that varies continuously in a second radial direction from the optical axis (102) to the peripheral region.

Description

Technical Field

[0001] The present disclosure relates particularly (but not exclusively) to ophthalmic lenses for slowing down myopia progression and for use by presbyopes, the lenses having different diopter variation curves. The present disclosure also relates to methods of manufacturing such lenses and methods of designing such lenses. Background Art

[0002] Many people, including children and adults, need ophthalmic lenses to correct myopia (nearsightedness) and many adults may need lenses to correct presbyopia (age-related inability to adapt and therefore focus on close objects). Ophthalmic lenses may also be needed to correct hyperopia (farsightedness), astigmatism, or keratoconus (a condition whereby the cornea gradually bulges to form a cone).

[0003] Without the use of optical correction, a myopic eye focuses incoming light from distant objects to a location in front of the retina. Thus, the light converges toward a plane in front of the retina, beyond which it then diverges and is out of focus when it reaches the retina. Conventional lenses used to correct myopia, such as spectacle lenses and contact lenses, reduce convergence (for contact lenses) or cause incoming light from distant objects to diverge (for spectacle lenses) before it reaches the eye, causing the focal position to shift onto the retina.

[0004] In presbyopia, the lens does not change shape effectively to accommodate near objects, and therefore a person with presbyopia is unable to focus on near objects. Conventional lenses (e.g., eyeglass lenses and contact lenses) used to correct presbyopia include bifocal lenses or progressive lenses that include an area optimized for near vision and an area optimized for distance vision. Presbyopia can also be treated using bifocal or multifocal lenses or single vision lenses (where different prescriptions are provided for each eye, one eye is provided with a distance vision lens, and one eye is provided with a near vision lens).

[0005] Decades ago it was suggested that the progression of myopia in children or young adults could be slowed or prevented by undercorrection (i.e., moving the focus toward but not completely onto the retina). However, such methods necessarily result in degraded distance vision compared to the vision obtained using a lens that fully corrects myopia. Furthermore, it is now doubtful that undercorrection is effective in controlling the progression of myopia. A more recent approach is to provide lenses with both fully corrected areas that provide distance vision and areas that are undercorrected or intentionally induce myopic defocus. Lenses can also be provided that increase the scattering of light in certain areas compared to light traveling through the fully corrected areas of the lens. It has been suggested that these methods can prevent or slow the progression or progression of myopia in children or young adults while providing good distance vision.

[0006] In the case of a lens with zones that provide defocus, the zone that provides full correction for distance vision is often referred to as a base power zone and the zone that provides undercorrection or intentionally induced myopic defocus is often referred to as a myopic defocus zone or an added power zone (because the power is more positive or less negative than the power of the distance zone). The surface (usually the front surface) of the added power zone has a smaller radius of curvature than the radius of curvature of the distance power zone and thus provides more positive or less negative power to the eye. The added power zone is designed to focus incoming parallel light (i.e., light from a distance) into the eye in front of the retina (i.e., closer to the lens), while the distance power zone is designed to focus light and form an image at the retina (i.e., farther away from the lens). When the lens wearer is looking near an object and uses accommodation to focus light traveling through the distance power zone, the added power zone focuses the light in front of the retina.

[0007] One known type of contact lens that reduces myopia progression is a bifocal contact lens available under the name MISIGHT (CooperVision, Inc.). This bifocal lens is different from bifocal or multifocal contact lenses that are configured to improve vision for presbyopes, where the bifocal lens is configured to have specific optical dimensions to enable an adaptable person to use distance correction (i.e., base power) to view both distant and near objects. The treatment area of ​​the bifocal lens with the added power also provides a myopic out-of-focus image at both distant and near viewing distances.

[0008] While these lenses have been found to be beneficial in preventing or slowing the development or progression of myopia, the annular additional power zone can produce unwanted visual side effects. Light focused in front of the retina by the annular additional power zone diverges from the focal point to form an out-of-focus ring at the retina. As a result, wearers of these lenses may see rings or 'halos' around the images formed on the retina, particularly for small bright objects such as street lamps and car headlights. Moreover, instead of using the eye's natural accommodation (i.e., the eye's natural ability to change focus) to bring nearby objects into focus, the wearer could, in theory, use the additional annular additional power zone to focus on near objects; in other words, the wearer could inadvertently use the lens in the same manner as a presbyopia correction lens, which is undesirable for young subjects.

[0009] Additional lenses have been developed that can be used to treat myopia. In these lenses, the annular zone is configured so that no single on-axis image is formed in front of the retina, thereby preventing this image from being used to focus near objects and avoiding the need for the eye to accommodate. Rather, a point source of distant light is imaged by the annular zone to an annular focal line at the near additional diopter focal plane, resulting in a small spot size of light on the retina at the distance focal plane, without a surrounding 'halo' effect.

[0010] To treat myopia, it will be appreciated that it may be beneficial to provide a lens that introduces additional myopic defocus. To treat presbyopia, it may be beneficial to provide a lens that produces an extended depth of focus. The present disclosure seeks to provide such a lens. Such lenses may also be beneficial in correcting or improving vision associated with hyperopia, astigmatism, keratoconus or other refractive errors. Summary of the invention

[0011] According to a first aspect, the present disclosure provides an ophthalmic lens according to technical solution 1.

[0012] According to a second aspect, the present disclosure provides a method for manufacturing a lens according to technical solution 23.

[0013] According to a second aspect, the present disclosure provides a method for designing a lens according to technical solution 24.

[0014] Of course, it should be appreciated that features described with respect to one aspect of the present disclosure may be incorporated into other aspects of the present disclosure. For example, the method of the present disclosure may incorporate features described with reference to the apparatus of the present disclosure and vice versa. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Embodiments of the present invention will now be described, by way of example only, with reference to the accompanying schematic drawings, in which:

[0016] Figure 1 is a diagram showing how the direction of the meridian is defined with respect to the lens;

[0017] Figure 2A is a schematic top view of a lens according to an embodiment of the present disclosure;

[0018] Figure 2B Is displayed along Figure 2A A diagram of the radial curvature diopters of the lens at two different meridians;

[0019] Figure 3A is a schematic top view of a lens according to another embodiment of the present disclosure;

[0020] Figure 3B Is displayed along Figure 3A A diagram of the radial curvature diopters of the lens at two different meridians;

[0021] Figure 4A is a schematic top view of a lens according to another embodiment of the present disclosure;

[0022] Figure 4B Is displayed along Figure 4A A diagram of the radial curvature diopters of the lens at two different meridians;

[0023] Figure 5Ais a schematic top view of a lens according to another embodiment of the present disclosure;

[0024] Figure 5B Is displayed along Figure 5A A diagram of the radial curvature diopters of the lens at two different meridians;

[0025] Fig. 6A is a schematic top view of a lens according to another embodiment of the present disclosure;

[0026] Figure 6B Is displayed along Fig. 6A A diagram of the radial curvature diopters of the lens at two different meridians;

[0027] Fig. 7A is a schematic top view of a lens according to another embodiment of the present disclosure;

[0028] Figure 7B Is displayed along Fig. 7A A diagram of the radial curvature diopters of the lens at two different meridians;

[0029] Figure 8 is a flow chart showing a method of manufacturing a lens according to an embodiment of the present disclosure; and

[0030] Fig. 9 is a flow chart illustrating a method of designing a lens according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0031] According to a first aspect, the present disclosure provides an ophthalmic lens. The lens comprises an optical zone centered on an optical axis and a peripheral zone surrounding the optical zone. Within the optical zone, along a first meridian, the lens has a first radial curvature refractive variable curve that continuously changes in a first radial direction from the optical axis to the peripheral zone. Along a second meridian, the lens has a second different radial curvature refractive variable curve that continuously changes in a second radial direction from the optical axis to the peripheral zone.

[0032] The ophthalmic lens may be a spectacle lens. The ophthalmic lens may be a contact lens.

[0033] Eyeglass lenses may include PMMA, CR-39, polycarbonate, Trivex, or crown glass.

[0034] As used herein, the term contact lens refers to a lens that can be placed on the front surface of the eye. It should be understood that such a contact lens will provide clinically acceptable on-eye movement and will not adhere to the person's (two) eyes. An ophthalmic lens can be a corneal lens (e.g., a contact lens that rests on the cornea of ​​the eye). An ophthalmic lens can be a soft contact lens, such as a hydrogel contact lens or a silicone hydrogel contact lens. An ophthalmic lens can be a rigid contact lens.

[0035] An ophthalmic lens may be a lens used to prevent or slow the development or progression of myopia. A lens may be a lens used to provide extended depth of focus for presbyopia.

[0036] An ophthalmic lens according to the present disclosure includes an optical zone. The optical zone encompasses the portion of the lens that is optically functional. The optical zone is configured to be positioned above the pupil of the eye when in use. For an ophthalmic lens according to the present disclosure, the optical zone includes a small central area, and an annular area surrounding the central area.

[0037] An ophthalmic lens according to an embodiment of the present disclosure includes a peripheral zone surrounding the optical zone. The peripheral zone is not part of the optical zone, but surrounds the optical zone and is located outside the optical zone. For embodiments of the present disclosure in which the ophthalmic lens is a contact lens, the peripheral zone is located above the iris when the lens is worn, and it provides a mechanical function, such as increasing the size of the lens, thereby making the lens easier to handle, providing a stable shaping area to prevent the lens from rotating and / or providing improved comfort for the lens wearer. The peripheral zone may extend to the edge of the contact lens. The peripheral zone may have a substantially circular outer periphery. In embodiments of the present disclosure in which the ophthalmic lens is a spectacle lens, the peripheral zone surrounds the optical zone and is located outside the optical zone. The peripheral zone may have a substantially circular outer periphery. The peripheral zone may have a substantially elliptical, oval or rectangular outer periphery. The peripheral zone may extend to the edge of the spectacle lens. The peripheral zone may be surrounded by another zone that is not optically active.

[0038] For embodiments of the present disclosure in which the ophthalmic lens is a contact lens, the peripheral zone may include a stabilizing portion to orient the lens when positioned on the wearer's eye. Embodiments of the present disclosure incorporating a stabilizing portion into a contact lens will rotate to a predetermined repose angle under the action of the wearer's eyelid when placed on the wearer's eye; for example, the stabilizing portion may be a wedge and the rotation may result from the action of the eyelid on the wedge. Stabilizing contact lenses to orient contact lenses is well known in the art; for example, stabilizing toric contact lenses to orient the lens so that the orthogonal cylindrical correction provided by the lens is properly aligned for the astigmatism of the wearer's eye.

[0039] For embodiments of the present disclosure in which the ophthalmic lens is a spectacle lens, the shape of the lens may be substantially circular. The shape of the lens may be elliptical. The shape of the lens may be oval. The shape of the lens may be rectangular. The shape of the lens may be square. The front surface of the lens may have a 1200 mm 2 With 3000mm 2 The area between.

[0040] In embodiments of the present disclosure where the ophthalmic lens is a contact lens, the lens may be substantially circular in shape and may have a diameter from about 4 mm to about 20 mm.

[0041] The optic zone of the ophthalmic lens may be substantially circular in shape and may have a diameter from about 2 mm to about 10 mm.

[0042] For embodiments of the present disclosure where the ophthalmic lens is a contact lens, the contact lens may have a diameter from 13 mm to 15 mm, and the optic zone may have a diameter from 7 mm to 9 mm.

[0043] The reference light is a distant point source defining the optical axis of the lens. Light from a distant point source on the optical axis of the lens (which may be referred to hereinafter as an on-axis distant point source) will be focused onto the optical axis of the lens. The optical axis may be located along the centerline of the lens. For example, when the lens is a contact lens, the optical axis is typically located along the centerline of the lens. However, the optical axis may of course not be along the centerline of the lens; this may be the case with spectacle lenses, the position of the optical axis of the lens will be determined by the wearer's pupillary distance, which may not coincide with the centerline of the lens depending on the geometry of the lens.

[0044] The power of a lens within the optical zone can be defined as sagittal curvature power, circumferential curvature power, sagittal sagittal power, and circumferential sagittal power.

[0045] In ophthalmology, the word "sagittal" is used in two different ways to describe oblique astigmatism and to describe optical surfaces.

[0046] In general optics, the word "sagittal" is used when describing oblique astigmatism. Oblique astigmatism occurs when light rays from an off-axis position pass through the lens obliquely. Astigmatism is primarily due to cosine compression occurring in the meridian along which the light rays originate, e.g., if the light rays originate from a horizontal peripheral field, then the surface (and therefore the radius of curvature) will exhibit cosine compression horizontally, resulting in an increase in power (and therefore astigmatism) in that meridian. The power in that meridian is labeled the "tangential" power, and the power in the perpendicular meridian is labeled the "sagittal" power. Astigmatism causes an object point to be imaged into two spatially separated and orthogonal line foci - the sagittal focal line and the tangential focal line.

[0047] The second usage of the word "sagittal" originates from the description of optical surfaces, for example in ophthalmology, where it is the center of clinical measurements of the anterior ocular surface (i.e., in corneal topography). Sagittal optical power is determined by the slope of the optical surface along a given direction; it is also called slope-based power. Terms including "sagittal power," "slope power," and "axial power" are synonyms that can be used interchangeably. Curvature power is determined by the local curvature of the optical surface along a given direction.

[0048] In this disclosure, the terms sagittal and curvature power may be used in the context of optical surfaces to describe the power of an ophthalmic lens surface.

[0049] Both sagittal and curvature powers are defined along a given direction. For an ophthalmic lens according to an embodiment of the present disclosure, the radial sagittal and radial curvature powers are along a direction extending radially outward from the optical axis of the lens. The circumferential sagittal and circumferential curvature powers are along a direction perpendicular to the radial direction.

[0050] For lenses with coaxial optics, the values ​​of sagittal power and curvature power may be similar or identical in the paraxial approximation. However, for some recently developed myopia control lenses that employ non-coaxial optics, the values ​​of slope and curvature power may be very different from each other. These lenses have a surface area that focuses light from an on-axis light source onto an area that is offset from the optical axis, so that the distance that a local beam of light from the light source reaches the focal point may be very different from the distance it crosses the optical axis. For these types of lenses, the distinction between sagittal and curvature power becomes important. For non-coaxial optics, a description of curvature power does not provide a complete description of the optics. Adjacent areas of a lens may have the same curvature power, but different sagittal powers (because the light from each area crosses the axis at different distances from the local focal length and from each other). For example, for a lens that includes non-coaxial lenslets, the resulting sagittal and curvature power values ​​are significantly different. The curvature power plot for this lens shows a constant add power per lenslet, but the sagittal power plot shows that the sagittal power decreases with increasing sagittal distance.

[0051] The sagittal power is directly related to the position of the rays at the image plane (the retinal plane in the eye), and therefore directly related to the image quality. This is not necessarily true for the curvature power when non-coaxial optics are implemented.

[0052] The sagittal and curvature powers of an ophthalmic lens can be determined by measuring the wavefront of light passing through the lens. When describing the optical wavefront passing through the lens, the sagittal power of the lens at a given point is related to the first derivative of the wavefront, as it is calculated as the slope of the wavefront divided by the radial distance (r) from the optical axis of the lens (usually the center of the lens). The radial (local) curvature power at that point is calculated as the second derivative of the wavefront.

[0053] In practice, an example method of measuring the wavefront of light passing through an ophthalmic lens is to use an aberrometer, such as a Shack-Hartmann aberrometer with a (monochromatic, i.e. narrow-band) 540 nm light source, e.g. (Available from www.lumetrics.com). The Shack-Hartmann aberrometer comprises a planar regular array of small mirrors. In use, the wavefront to be measured is sampled by a two-dimensional array of small mirrors (lenses) that each focus a different part of the wavefront to a different focal point. If the wavefront is planar, then the spatial arrangement of the resulting point spread function will reflect the arrangement of the mirrors, so that the mirrors focus the wavefront to a corresponding regular array of focal spots.

[0054] Optical wavefront measurements derived from an aberrometer are usually quantified relative to a standard reference situation. For example, when using a Shack-Hartmann aberrometer, the standard reference is usually a plane wavefront passing through a two-dimensional array of mirrorlets (lenses), as described previously.

[0055] The effect of a given lens on the wavefront is measured by inserting the lens into the measurement path at a position optically conjugate to the lenslet array. The plane wavefront then passes through the two-dimensional lenslet array and through the lens.

[0056] For a simple lens, the resulting wavefront will be a diverging or converging wavefront, and when the lens is not present, an array of spots will be produced that are displaced relative to their position. In practice, the magnitude and direction of the spot displacements may also be caused by additional aberrations of the lens. A wavefront error map is determined by measuring the displacement of the displaced spots from a regular array of focal spots, and the wavefront error map can be used to calculate the sagittal and curvature powers of the lens.

[0057] The wavefront error map can be measured at intervals across the lens, such as across the optic zone of a contact lens; for example, a Shack-Hartmann aberrometer can be used to measure the wavefront error map every 104 μm over a 10 mm aperture.

[0058] For the lenses described herein and in accordance with embodiments of the present disclosure, the sagittal power (i.e., slope power or axial power) at a given position is the first derivative of the wavefront error (i.e., wavefront error slope, such as can be obtained from a wavefront error map) with respect to r, divided by r, where r is the radial distance of the position from the optical axis of the lens; therefore, the sagittal power is defined as

[0059]

[0060] For the lenses described herein and in accordance with embodiments of the present disclosure, the radial curvature power at a given location is the second derivative of the wavefront error with respect to r (which can be obtained, for example, from a wavefront error map), where r is the radial distance of that location from the optical axis of the lens; the radial curvature power is thus defined as:

[0061]

[0062] The term meridian is used herein to describe a line extending radially outward from the optical axis within the optical zone to a point on the boundary between the optical zone and the peripheral zone. The direction of a meridian around the optical zone can be defined by an angle θ, where θ varies between 0° and 360°. Figure 1 In the description. Figure 1 A lens 1 is shown having an optical zone 3 centered on an optical axis 2. A peripheral zone 5 surrounds the optical zone 3. A first example meridian 7a is located along a line θ=0 / 360° and extends from the optical axis 2 to a boundary 9 of the optical zone 3 and the peripheral zone 5. A second example meridian 7b is located along a line θ=90° and extends from the optical axis 2 to a boundary 9 of the optical zone 3 and the peripheral zone 5. A third example meridian 7c is located along a line θ=180° and extends from the optical axis 2 to a boundary 9 of the optical zone 3 and the peripheral zone 5. A fourth example meridian 7d is located along a line θ=270° and extends from the optical axis 2 to a boundary 9 of the optical zone 3 and the peripheral zone 5. Although in Figure 1 Only four orthogonal meridians are shown in FIG. 1 , but the meridians are located along the lines of all values ​​of θ, i.e., 0°<=θ<360°. In addition, the degree of each meridian is referred to the accompanying drawings. It can be understood that in the field of contact lenses, for example, Figure 1 The 90-degree meridian shown in the figure can actually be understood as the 0 / 360-degree meridian, and Figure 1 The 0 / 360 degree meridian shown in can be understood as a 90 degree meridian, so that the degrees of each meridian increase in a counterclockwise direction.

[0063] In an embodiment of the present disclosure, the radial curvature power of the optical zone varies continuously (i.e., has a smooth and continuous change in value) in a radial direction along a first meridian (i.e., in a radial direction extending outward from the optical axis of the lens to a point in the boundary between the optical zone and the peripheral zone), thereby generating a first radial curvature diopter variation curve. A first average radial curvature power can be defined as the average radial curvature power value measured along the meridian having the first radial curvature diopter variation curve.

[0064] At or toward the optical axis, the first radial curvature refractive diopter curve may provide a distance diopter. At the optical axis, the first radial curvature refractive diopter curve may provide a diopter between +0.5 diopters (D) and -25.0D. The first radial curvature refractive diopter curve may provide a diopter between -0.25D and -15.0D. Alternatively, the first radial curvature refractive diopter curve may provide a near diopter. At the optical axis, the first radial curvature refractive diopter curve may provide a diopter between +0.5 diopters (D) and +25.0D. At the optical axis, the first radial curvature refractive diopter curve may provide a diopter between +0.5 diopters (D) and +10.0D.

[0065] In embodiments of the present disclosure, along at least one second different meridian within the optical zone (i.e., a second radial direction extending outward from the optical axis of the lens to a point on the boundary between the optical zone and the peripheral zone), the radial curvature power also varies continuously (i.e., has a smooth and continuous change in value), but exhibits a radial curvature power variation that is different from the first radial curvature power variation curve, thereby producing a second different radial curvature power variation curve. A second average radial curvature power may be defined as the average radial curvature power values ​​taken along the meridian having the second radial curvature power variation curve. The second average radial curvature power may be different from the first average radial curvature power. The second average radial curvature power may be the same as the first average radial curvature power.

[0066] Advantageously, lenses according to embodiments of the present disclosure having different curvature diopter curves along different meridians can allow eye muscles to relax. This is particularly useful in lenses used to improve vision at everyday working distances and can produce an anti-fatigue effect.

[0067] At or towards the optical axis, the second radial curvature refractive diopter curve may provide a distance diopter. At the optical axis, the second radial curvature refractive diopter curve may provide a diopter between +0.5 diopters (D) and -25.0D. The second radial curvature refractive diopter curve may provide a diopter between -0.25D and -15.0D. Alternatively, the second radial curvature refractive diopter curve may provide a near diopter. At the optical axis, the second radial curvature refractive diopter curve may provide a diopter between +0.5 diopters (D) and +25.0D. At the optical axis, the second radial curvature refractive diopter curve may provide a diopter between +0.5 diopters (D) and +10.0D.

[0068] At the optical axis, the second radial curvature diopter variation curve may have the same radial curvature diopter as the first radial curvature diopter variation curve. Alternatively, the first radial curvature diopter variation curve and the second radial curvature diopter variation curve may approach two different radial curvature diopter values. Towards the optical axis, the first curvature diopter variation curve or the second curvature diopter variation curve may provide a distance diopter, and the other of the first curvature diopter variation curve and the second curvature diopter variation curve may provide a near diopter. Thus, advantageously, the lens may provide both a central near diopter and a central distance diopter.

[0069] The first radial curvature diopter variation curve and the second radial curvature diopter variation curve may have the same or similar radial curvature diopter value at or toward the optical axis, but may have different radial curvature diopter values ​​at or toward the boundary between the optical zone and the peripheral zone. Alternatively, the first radial curvature diopter variation curve and the second radial curvature diopter variation curve may have the same or similar or may have different radial curvature diopter values ​​at or toward the boundary between the optical zone and the peripheral zone.

[0070] Along the first radial curvature diopter variation curve, the radial curvature diopter may vary with an oscillating diopter variation curve. Along the first radial curvature diopter variation curve, the radial curvature diopter may continuously increase, or continuously decrease. The first radial curvature diopter variation curve may have a monotonic decrease in radial curvature diopter with increasing radial distance from the optical axis, or a monotonic increase in radial curvature diopter with increasing radial distance from the optical axis. The gradient of the first radial curvature diopter variation curve may be constant, or may change with increasing radial distance from the optical axis. Along the first radial curvature diopter variation curve, the radial curvature diopter may vary in a pseudo-random manner.

[0071] Along the second radial curvature diopter variation curve, the radial curvature diopter may vary with an oscillating diopter variation curve. Along the second radial curvature diopter variation curve, the radial curvature diopter may increase continuously, or decrease continuously. The second radial curvature diopter variation curve may show a monotonic decrease in radial curvature diopter with increasing radial distance from the optical axis, or a monotonic increase in radial curvature diopter with increasing radial distance from the optical axis. The gradient of the second radial curvature diopter variation curve may be constant, or may change with increasing radial distance from the optical axis. Along the second radial curvature diopter variation curve, the radial curvature diopter may vary in a pseudo-random manner.

[0072] The first radial curvature diopter profile may be selected to produce a desired first mean radial curvature diopter value along a first meridian.The second radial curvature diopter profile may be selected to produce a second mean radial curvature diopter along a second meridian.

[0073] The first radial curvature refractive index variation curve may have substantially the same shape as the second radial curvature refractive index variation curve, but the first mean radial curvature diopter may be different from the second mean radial curvature diopter. Alternatively, the first curvature refractive index variation curve may have a first mean radial curvature diopter value measured along a first meridian, and the second radial curvature refractive index variation curve may also have a first mean radial curvature diopter value measured along a second meridian, and the first radial curvature refractive index variation curve may have a different shape than the second radial curvature refractive index variation curve.

[0074] The first radial curvature refractive power curve may have a shape opposite to the second radial curvature refractive power curve. For example, one of the first curvature refractive power curve and the second curvature refractive power curve may include at least one peak at a first radial distance from the optical axis of the lens, and the other of the first curvature refractive power curve and the second curvature refractive power curve may include at least one valley at the first radial distance from the optical axis of the lens. The first radial curvature refractive power curve may include a series of peaks at a series of radial positions along the meridian, while the second radial curvature refractive power curve may include a series of valleys at the same radial positions along the meridian. In this case, the first average radial curvature power may be the same as the second average radial curvature power, or it may be different from the second average radial curvature power. In this article, the term peak may be used to describe the maximum radial (i.e., most positive or least negative) curvature power value along the radial curvature refractive power curve. A peak may be a global peak (i.e., the absolute maximum radial curvature diopter value along the radial curvature refractive measurement curve), or a local peak (i.e., the maximum radial curvature diopter value compared to the radial curvature diopter values ​​on either side of the peak). The term valley may be used to describe the minimum (i.e., the smallest positive or most negative) radial curvature diopter value along the radial curvature refractive measurement curve. A valley may be a global valley (i.e., the absolute minimum radial curvature diopter value along the radial curvature refractive measurement curve), or a local peak (i.e., the minimum radial curvature diopter value compared to the radial curvature diopter values ​​on either side of the valley).

[0075] One of the first radial curvature refractive index variation curve and the second radial curvature refractive index variation curve may have a higher curvature refractive index value (i.e., more positive or less negative) toward the optical axis than toward the boundary between the peripheral zone and the optical zone, and the other of the first radial curvature refractive index variation curve and the second radial curvature refractive index variation curve may have a lower curvature refractive index value (i.e., less positive or more negative) toward the optical axis than toward the boundary between the peripheral zone and the optical zone. One of the first radial curvature refractive index variation curve and the second radial curvature refractive index variation curve may increase monotonically with increasing distance from the optical axis. The other of the first radial curvature refractive index variation curve and the second radial curvature refractive index variation curve may decrease monotonically with increasing distance from the optical axis.

[0076] The first radial curvature refractive power variation curve may include at least one peak in the radial curvature power. The first radial curvature refractive power variation curve may include at least one valley in the radial curvature power. The first radial curvature refractive power variation curve may include multiple peaks and / or valleys in the radial curvature power at different radial distances from the optical axis of the lens. The different peaks and / or valleys in the first radial curvature refractive power variation curve may be global or local peaks and / or valleys, i.e., they may have different radial curvature power values. The second radial curvature refractive power variation curve may include at least one peak in the radial curvature power. The second radial curvature refractive power variation curve may include at least one valley in the radial curvature power. The second radial curvature refractive power variation curve may include multiple peaks and / or valleys in the radial curvature power at different radial distances from the optical axis of the lens. The different peaks and / or valleys in the second radial curvature refractive power variation curve may be global or local peaks and / or valleys, i.e., they may have different radial curvature powers.

[0077] At least one peak and / or valley in the first radial curvature refractive index curve may be at the same radial distance from the optical axis of the lens as at least one peak and / or valley in the second radial curvature refractive index curve. Each peak and / or valley in the first radial curvature refractive index curve may be at the same radial distance from the optical axis of the lens as each peak and / or valley in the second radial curvature refractive index curve. Each peak in the first radial curvature refractive index curve may be at the same radial distance from the optical axis of the lens as a valley in the second radial curvature refractive index curve, or vice versa.

[0078] The first radial curvature refractive measurement curve may span a diopter range of at least 2.0D, preferably at least 5.0D. The second radial curvature refractive measurement curve may span a diopter range of at least 2.0D, preferably at least 5.0D. The first radial curvature refractive measurement curve and the second radial curvature refractive measurement curve may span a diopter range having the same magnitude, for example, both the first radial curvature refractive measurement curve and the second radial curvature refractive measurement curve may span a 5.0D diopter range. The first radial curvature refractive measurement curve and the second radial curvature refractive measurement curve may span different absolute diopter values. The range of diopter values ​​spanned by the first radial curvature refractive measurement curve may overlap with the range of diopter values ​​spanned by the second radial curvature refractive measurement curve.

[0079] The first and second radial curvature diopter profiles may have substantially the same shape but may span different diopter values, which may be overlapping diopter ranges or may be non-overlapping diopter values.

[0080] In the optical zone, a first set of meridians may have a first curvature diopter variation curve, and a second set of meridians may have a second curvature diopter variation curve. The first curvature diopter variation curve may have a first mean radial curvature diopter, and thus, the first set of meridians may have a first mean radial curvature diopter. The second radial curvature diopter variation curve may have a second mean radial curvature diopter value, and thus, the second set of meridians may have a second mean radial curvature diopter.

[0081] The first set of meridians may be distributed at regular intervals (i.e., at regularly spaced θ values) around the optical zone. The angular spacing between each meridian in the first set of meridians may be about 90°, about 45°, about 30°, about 20°, or about 10°. The angular spacing between each meridian in the first set of meridians may be less than 5°, less than 2°, less than 1°, or less than 0.5°. The second set of meridians may be distributed at regular intervals (i.e., at regularly spaced θ values) around the optical zone. The angular spacing between each meridian in the set of meridians may be about 90°, about 45°, about 30°, about 20°, or about 10°. The angular spacing between each meridian in the first set of meridians may be less than 5°, less than 2°, less than 1°, or less than 0.5°. The first set of meridians and the second set of meridians may be staggered, and they may form an alternating pattern around the optical zone. The angular spacing between a meridian in the first set of meridians and its adjacent meridian from the second set of meridians may be less than 5°, less than 2°, less than 1°, or less than 0.5°. The angular spacing between a meridian from the first set of meridians and its adjacent meridian from the second set of meridians may be small enough that the eye of the lens wearer cannot distinguish between the two meridians.

[0082] The average radial curvature power of meridians in a first direction may be different from the average radial curvature power of meridians in a second orthogonal direction, resulting in a toric mean diopter profile. For example, the second set of meridians may be orthogonal to the first set of meridians (i.e., each meridian in the first set of meridians having a first average radial curvature power may be orthogonal to a meridian in the second set of meridians having a second average radial curvature power). Thus, the optical zone of the lens may have a toric diopter profile.

[0083] A first set of meridians distributed at regular intervals around the optical zone may have a first mean radial curvature power, and a second set of meridians distributed at regular intervals around the optical zone may have a second mean curvature diopter profile. Alternatively, the second set of meridians having the second mean radial curvature power may form an alternating pattern with the first set of meridians having the second mean radial curvature power. Thus, the first set of meridians and the second set of meridians may result in a star-shaped diopter profile, wherein the periodic variation in radial curvature power moves in a circumferential direction around the optical zone. The angular spacing between a meridian from the first set of meridians having the first mean radial curvature power and an adjacent meridian from the second set of meridians having the second mean radial curvature power may be less than 1°.

[0084] Along at least one other meridian in the optical zone, the radial curvature power may vary along a third radial curvature power curve that is different from the second curvature power curve and the first curvature power curve.

[0085] The radial curvature diopter variation curve along the meridians within the optical zone can vary continuously with angle θ. Each meridian around the optical zone can have a peak in radial curvature diopter at a different radial distance of each meridian from the optical axis. Thus, the location of the peak or valley along each meridian (i.e., the radial distance of the peak or valley from the optical axis of the lens) can vary with angle θ. The location of the peak or valley around the circumference of the optical zone can define a portion of a spiral, i.e., the radial distance of the peak or valley from the optical axis can increase as angle θ increases or can decrease as angle θ increases.

[0086] The radial curvature power of the optical zone may be derived from the curvature of the front surface of the lens.The radial curvature power of the optical zone may be derived from the curvature of the back surface of the lens.The radial curvature power of the optical zone may be derived from the combination of the curvatures of the front and back surfaces of the lens.

[0087] For embodiments of the present disclosure in which the ophthalmic lens is a contact lens, the lens may include an elastomeric material, a silicone elastomeric material, a hydrogel material, or a silicone hydrogel material, or a combination thereof. As understood in the field of contact lenses, a hydrogel is a material that keeps water in a state of equilibrium and is free of silicone-containing chemicals. A silicone hydrogel is a hydrogel containing silicone-containing chemicals. As described in the context of the present disclosure, the hydrogel material and the silicone hydrogel material have an equilibrium water content (EWC) of at least 10% to about 90% (wt / wt). In some embodiments, the hydrogel material or the silicone hydrogel material has an EWC of from about 30% to about 70% (wt / wt). In contrast, as described in the context of the present disclosure, the silicone elastomeric material has a water content of from about 0% to less than 10% (wt / wt). Generally speaking, the silicone elastomeric material used with the method or apparatus of the present invention has a water content of from 0.1% to 3% (wt / wt). Examples of suitable lens formulations include lens formulations with 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, nofilcon)A, sanofilcon B, sanofilcon C, narafilcon A, narafilacon B, balafilcon A, samfilcon A, lotrafilcon A, lotrafilcon B, somofilcon A, riofilcon A, delefilcon A, verofilcon A, kalifilcon A and the like.

[0088] Alternatively, the lens may include, consist essentially of, or consist of a silicone elastomeric material. For example, the lens may include, consist essentially of, or consist of a silicone elastomeric material having a Shore A hardness from 3 to 50. The Shore A hardness may be determined using conventional methods as understood by one of ordinary skill in the art (e.g., using method DIN 53505). For example, other silicone elastomeric materials may be obtained from NuSil Technology or Dow Chemical Company.

[0089] According to a second aspect, the present disclosure provides a method of manufacturing a lens. The lens may comprise any of the features set out above in relation to the first aspect of the invention. The method may comprise forming the lens.

[0090] For embodiments of the present disclosure in which the ophthalmic lens is a contact lens, the manufacturing method may include forming a female mold part having a concave lens forming surface and a male mold part having a convex lens forming surface. The method may include filling a gap between the female and male mold parts with a bulk lens material. The method may further include curing the bulk lens material to form the lens.

[0091] For embodiments of the present disclosure in which the ophthalmic lens is a contact lens, the lens may be formed using a turning process. The lens may be formed by a cast molding process, a spincast molding process, or a turning process, or a combination thereof. As understood by those skilled in the art, cast molding refers to molding a lens by placing a lens forming material between a female mold member having a concave lens component forming surface and a male mold member having a convex lens component forming surface.

[0092] According to a third aspect, the present disclosure provides a method of designing a lens. The lens may include any of the features set forth above. The method includes selecting a first mean radial curvature diopter value, and selecting a second, different mean radial curvature diopter value. The method includes designing a first curvature diopter variation curve that produces the first mean radial curvature diopter value and designing a second curvature diopter variation curve that produces the first mean radial curvature diopter value. The method includes designing an optical zone of the lens, wherein the optical zone includes a meridian having the first curvature diopter variation curve and a meridian having the second curvature diopter variation curve.

[0093] Figure 2A A schematic top view of a lens 101 according to an embodiment of the present disclosure is shown. The lens 101 includes an optical zone 103 centered on the optical axis 102 and a peripheral zone 105 surrounding the optical zone 103. A first meridian 107a (only a single meridian 107a is labeled, the other meridians in the group are indicated using dotted lines) forming part of a set of first meridians 107a extends from the optical axis 102 to a boundary 109 between the optical zone 103 and the peripheral zone 105. Along the first meridian 107a, the radial curvature power varies smoothly and continuously and has a first radial curvature power variation curve 111a, as shown in FIG. Figure 2B1. The first radial curvature diopter variation curve 111a oscillates between peaks 113a and valleys 115a. The two peaks 113a have the same radial curvature diopter value, and the two valleys 115a have the same radial curvature diopter value. The second meridian 107b extends from the optical axis 102 to the boundary 109 of the optical zone 103 and the peripheral zone 105. The second meridian 107b forms part of a group of second meridians 107b (only a single meridian 107b is marked, the other meridians in the group are indicated using dashed lines), and also has a radial curvature diopter that varies smoothly and continuously with the second radial curvature diopter variation curve 111b, as shown in FIG. Figure 2B 11. This second radial curvature refractive power profile 111b also oscillates between peaks 113b and valleys 115b, but has an opposite variation to the first radial curvature refractive power profile 111a, such that the valleys 115b of the second radial curvature refractive power profile 111b are at the same radial distance from the optical axis 102 as the peaks 113a of the first radial curvature refractive power profile 111a, and vice versa. The first radial curvature refractive power profile 111a and the second radial curvature refractive power profile 111b have the same average radial curvature power indicated by the dashed line 117.

[0094] like Figure 2A As shown in FIG. 1 , around the optical zone 103, there is a diopter variation curve 111a having a first radial curvature (see Figure 2B ) of the first group of meridians 107a and the second group of meridians 107a and the second group of meridians 107a and the first ... Figure 2B ). The angular spacing between each of the meridians 107a in the first group is about 45°, and the angular spacing between each of the meridians 107b in the second group is about 45°, so that the angular spacing between a meridian 107a from the first group and its adjacent meridian from the second group is about 22.5°.

[0095] Figure 3A A schematic top view of a lens 201 according to another embodiment of the present disclosure is shown. The lens 201 includes an optical zone 203 centered on the optical axis 202 and a peripheral zone 205 surrounding the optical zone 203. A first meridian 207a forming part of a set of first meridians 207a (only a single meridian 207a is marked, the other meridians in the set are indicated using dotted lines) extends from the optical axis 202 to a boundary 209 between the optical zone 203 and the peripheral zone 205. Along the first meridian 207a, the radial curvature diopter varies smoothly and continuously and has a first radial curvature diopter variation curve 211a, as shown in FIG. Figure 3B In the Figure 3BA first radial curvature diopter variation curve 211a along this first meridian 207a is shown in FIG. The first radial curvature diopter variation curve 211a has a radial curvature diopter value that decreases with increasing distance from the optical axis 202. The gradient of the radial curvature diopter variation curve 211a varies with distance from the optical axis 202.

[0096] The second meridian 207b extends from the optical axis 202 to the boundary 209 between the optical zone 203 and the peripheral zone 205. Along the second meridians 207b forming part of a group of second meridians 207b (only a single meridian 207b is marked, the other meridians in the group are indicated using dashed lines), the radial curvature power also varies smoothly and continuously, and has a second radial curvature power variation curve 211b, as shown in FIG. Figure 3B 21. The second radial curvature refractive index variation curve 211b has a radial curvature diopter value that increases with increasing radial distance from the optical axis 202. The gradient of the radial curvature refractive index variation curve 211b varies with the distance from the optical axis 202. The second radial curvature refractive index variation curve 211b shows an opposite variation to the first radial curvature refractive index variation curve 211a. The first radial curvature refractive index variation curve 211a and the second radial curvature refractive index variation curve 211b have the same average radial curvature diopter indicated by the dashed line 217.

[0097] like Figure 3A As shown in FIG. 2 , around the optical zone 203, there is a diopter variation curve 211a having a first radial curvature (see Figure 3B ) of the first group of meridians 207a and the second group of meridians 207a and the second group of meridians 207a and the first ... 207b from the second group of meridians 207a and 207b having a second radial curvature refractive index curve 211b (see Figure 3B ). The angular spacing between each of the meridians 207a in the first group is about 10°, and the angular spacing between each of the meridians 207b in the second group is about 10°, so that the angular spacing between a meridian 207a from the first group and its adjacent meridian 207b from the second group is about 5°.

[0098] Figure 4A A schematic top view of a lens 301 according to another embodiment of the present disclosure is shown. The lens 301 includes an optical zone 303 centered on the optical axis 302 and a peripheral zone 305 surrounding the optical zone 303. A first meridian 307a (only a single meridian is labeled, the other meridians 307a in the group are indicated using dotted lines) forming part of a set of first meridians 307a extends from the optical axis 302 to a boundary 309 between the optical zone 303 and the peripheral zone 305. Along the first meridian 307a, the radial curvature power varies smoothly and continuously and has a first radial curvature power variation curve 311a, as shown in FIG. Figure 4B. A first radial curvature diopter variation curve 311a along this first meridian 307a has a radial curvature diopter value that decreases with increasing distance from the optical axis 302. The gradient of the first radial curvature diopter variation curve 311a varies with the distance from the optical axis 302. A second meridian 307b extends from the optical axis 302 to a boundary 309 of the optical zone 303 and the peripheral zone 305. Along a second meridian 307b forming part of a set of second meridians 307b (only a single meridian is labeled, the other meridians 307b within the set are indicated using dashed lines), the radial curvature diopter also varies smoothly and continuously and has a second radial curvature diopter variation curve 311b, as shown in FIG. Figure 4B The second radial curvature diopter variation curve 311b along the second meridian 307b also has a radial curvature diopter value that decreases as the distance from the optical axis 302 increases.

[0099] At the optical axis 302 (by Figure 4B The first radial curvature refractive power curve 311a has a higher radial curvature refractive power value than the second radial curvature refractive power curve 311b. At the boundary between the optical zone 302 and the peripheral zone 305 (indicated by the point marked with 'X' in FIG. Figure 4B 'Y' in the figure), the first radial curvature refractive index curve 311a has the same radial curvature diopter value as the second radial curvature refractive index curve. The first radial curvature refractive index curve 311a has a higher average radial curvature diopter (indicated by dashed line 317a) than the average radial curvature diopter (indicated by dashed line 317b) of the second radial curvature refractive index curve 311b.

[0100] like Figure 4A As shown in FIG. 3 , around the optical zone 303, there is a diopter variation curve 311a having a first radial curvature (see Figure 4B ) of the first group of meridians 307a and the second group of meridians 307a and the second group of meridians 307a and the first ... 307b from the second group of meridians 307a and 307b having a second radial curvature refractive index curve 311b (see Figure 4B ). The angular spacing between each of the meridians 307a in the first group is about less than 2°, and the angular spacing between each of the meridians 307b in the second group is about 2°, so that the angular spacing between a meridian 307a from the first group and its adjacent meridian 307b from the second group is less than 1°. When the lens 301 is worn by a lens wearer, the lens wearer's eye will not be able to resolve the two different radial curvature diopter profiles.

[0101] Figure 5AA schematic top view of a lens 401 according to another embodiment of the present disclosure is shown. The lens 401 includes an optical zone 403 centered on the optical axis 402 and a peripheral zone 405 surrounding the optical zone 403. A first meridian 407a (only a single meridian is labeled, the other meridians 407a in the group are indicated using dotted lines) forming part of a set of first meridians 407a extends from the optical axis 402 to a boundary 409 between the optical zone 403 and the peripheral zone 405. Along the first meridian 407a, the radial curvature power varies smoothly and continuously and has a first radial curvature power variation curve 411a, as shown in FIG. Figure 5B . A first radial curvature diopter variation curve 411a along this first meridian 407a varies in a pseudo-random manner, with a peak in the radial curvature diopter at a first radial distance from the optical axis (indicated by dashed line 412a). The gradient of the first radial curvature diopter variation curve 411a varies with the distance from the optical axis 402. A second meridian 407b extends from the optical axis 402 to a boundary 409 between the optical zone 403 and the peripheral zone 405. Along a second meridian 407b forming part of a group of second meridians 407b (only a single meridian is labeled, the other meridians 407b within the group are indicated using dashed lines), the radial curvature diopter also varies smoothly and continuously, with a second radial curvature diopter variation curve 411b, as shown in FIG. Figure 5B The second sagittal curvature diopter variation curve 411b along this second meridian 407b varies in a pseudo-random manner, with peaks in the sagittal curvature diopter (indicated by dashed lines 412b) at second different distances from the optical axis.

[0102] like Figure 5A As shown in FIG. 4 , around the optical zone 403, there is a diopter variation curve 411a having a first radial curvature (see Figure 5B ) of the first group of meridians 407a and the second group of meridians 407a and the second group of meridians 407a and the first ... 407b from the second group of meridians 407a having a second radial curvature refractive index curve 411b (see Figure 5B ). The angular spacing between each of the meridians 407a in the first group is about less than 2°, and the angular spacing between each of the meridians 407b in the second group is about 2°, so that the angular spacing between a meridian 407a from the first group and its adjacent meridian 407b from the second group is less than 1°. When the lens 401 is worn by a lens wearer, the lens wearer's eye will not be able to resolve the two different radial curvature diopter curves.

[0103] Fig. 6AA schematic top view of a lens 501 according to another embodiment of the present disclosure is shown. The lens 501 includes an optical zone 503 centered on the optical axis 502 and a peripheral zone 505 surrounding the optical zone. A first meridian 507a (dotted line) extends from the optical axis 502 to a boundary 509 between the optical zone 503 and the peripheral zone 505. Along the first meridian 507a, the radial curvature diopter changes smoothly and continuously and has a first radial curvature diopter variation curve 511a, as shown in FIG. Figure 6B . A first radial curvature diopter variation curve 511a along this first meridian 507a has a peak in the radial curvature diopter at a first radial distance from the optical axis (indicated by dashed line 512a). A second meridian 507b (dashed line) extends from the optical axis 502 to the boundary 509 of the optical zone 503 and the peripheral zone 505. Along the second meridian 507b, the radial curvature diopter also varies smoothly and continuously, with a second radial curvature diopter variation curve 511b, as shown in FIG. Figure 6B . A second radial curvature diopter variation curve 511b along this second meridian 507b has a peak in the radial curvature diopter at a second radial distance from the optical axis (indicated by dashed line 512b). A third meridian 507c (dashed line) extends from the optical axis 502 to the boundary 509 of the optical zone 503 and the peripheral zone 505. Along the third meridian 507c, the radial curvature diopter also varies smoothly and continuously, with a third radial curvature diopter variation curve 511c, as shown in FIG. Figure 6B 507c. A third radial curvature diopter variation curve 511c along this third meridian 507c has a peak in radial curvature diopter at a third radial distance from the optical axis (indicated by dashed line 512c). Around the optical zone 503 (i.e., with a different angle θ), each meridian has a peak in radial curvature diopter at a different distance from the optical axis. Thus, the peak defines a portion of a spiral extending in a circumferential direction around the optical zone 503.

[0104] like Fig. 6A As shown in FIG. 5 , around the optical zone 503 , the angular spacing between meridians 507a , 507b , 507c is approximately 2°.

[0105] Fig. 7A A schematic top view of a lens 601 according to another embodiment of the present disclosure is shown. The lens 601 includes an optical zone 603 centered on an optical axis 602 and a peripheral zone 605 surrounding the optical zone 603. A first meridian 607a extends from the optical axis 602 to a boundary 609 between the optical zone 603 and the peripheral zone 605. Along the first meridian 607a, the radial curvature diopter changes smoothly and continuously and has a first radial curvature diopter variation curve 611a, as shown in FIG. Figure 7B. A first radial curvature diopter variation curve 611a along this first meridian 607a varies in a pseudo-random manner, with a global peak (i.e., an absolute maximum) in the radial curvature diopter at a first radial distance from the optical axis (indicated by dashed line 612a). The gradient of the first radial curvature diopter variation curve 611a varies with the distance from the optical axis 602. A second meridian 607b extends from the optical axis 602 to a boundary 609 of the optical zone 603 and the peripheral zone 605. The second meridian 607b is orthogonal to the first meridian 607a, wherein the first meridian 607a is positioned along the line θ=0° and the second meridian 607b is positioned along the line θ=90°. Along the second meridian 607b, the radial curvature diopter also varies smoothly and continuously, with a second radial curvature diopter variation curve 611b, as shown. Figure 7B The second radial curvature refractive power variation curve 611b along this second meridian 607b varies in a pseudo-random manner, with a global peak (i.e., an absolute maximum) in the radial curvature refractive power at a second different distance from the optical axis (indicated by dashed line 612b). The average radial curvature refractive power of the first radial curvature refractive power variation curve 611a (indicated by dashed line 612b) is Figure 7B The dashed line 617a in FIG. 6 shows a second radial curvature diopter 611b having an average radial curvature diopter (indicated by Figure 7B 617a is higher. The first meridian 607a is part of a group of first meridians having a first radial curvature refractive measurement curve 611a (only one first meridian 607a is marked, the other first meridians are indicated as dotted lines). The second meridian 607b is part of a group of second meridians having a second radial curvature refractive measurement curve 611b (only one second meridian 607b is marked, the other second meridians are indicated as dotted lines). Each meridian in the first group of meridians has a corresponding orthogonal meridian as part of the second group of meridians (only one first meridian 607a is marked, the other first meridians are indicated as dotted lines), that is, each meridian having a first radial curvature refractive measurement curve 611a is positioned at 90° to a meridian having a second radial curvature refractive measurement curve 611b. Therefore, the optical zone 603 of the lens 601 has a toric refractive measurement curve.

[0106] Figure 81001 is a flow chart showing a method 1001 of manufacturing a lens according to an embodiment of the present disclosure. The lens includes an optical zone centered on the optical axis and a peripheral zone surrounding the optical zone. Within the optical zone, along a first meridian, the lens has a first radial curvature diopter variation curve that continuously changes in a first radial direction from the optical axis to the peripheral zone. Along a second meridian, the lens has a second different radial curvature diopter variation curve that continuously changes in a second radial direction from the optical axis to the peripheral zone. The lens may include any of the features stated above. In a first step 1003, the method includes forming a female mold part having a concave lens forming surface and a male mold part having a convex lens forming surface. In a second step 1005, the method includes filling a gap between the female and male mold parts with a bulk lens material. In a third step 1007, the method includes curing the bulk lens material to form the lens.

[0107] In alternative embodiments of the present disclosure, the lens may be formed using a lathe process, a spincast molding process, or a turning process, or a combination thereof.

[0108] Fig. 9 is a flow chart showing a method 2001 of designing a lens according to an embodiment of the present disclosure. The lens comprises an optical zone centered on an optical axis and a peripheral zone surrounding the optical zone. Within the optical zone, along a first meridian, the lens has a first radial curvature diopter profile that varies continuously in a first radial direction from the optical axis to the peripheral zone. Along a second meridian, the lens has a second different radial curvature diopter profile that varies continuously in a second radial direction from the optical axis to the peripheral zone. The lens may comprise any of the features set forth above. In a first step 2003, the method comprises selecting a first mean radial curvature diopter value. In a second step 2005, the method comprises selecting a second different mean radial curvature diopter value. In a third step 2007, the method comprises designing a first curvature diopter profile that produces a first mean radial curvature diopter value. In a fourth step 2009, the method comprises designing a second curvature diopter profile that produces the first mean radial curvature diopter value. In a sixth step 2011, the method comprises designing an optical zone of the lens, wherein the optical zone comprises a meridian having a first diopter profile of curvature and a meridian having a second diopter profile of curvature.

[0109] Those of ordinary skill in the art will appreciate that the features of these example embodiments may be combined in other embodiments that fall within the scope of the present disclosure. Although the present disclosure has been described and illustrated with reference to specific example embodiments, those of ordinary skill in the art will appreciate that the present disclosure lends itself to many different variations that are not specifically described herein. By way of example only, certain possible variations will now be described.

[0110] In the example embodiments of the present disclosure described above, the lens is substantially circular and has a peripheral zone having a substantially circular outer periphery surrounding the optical zone. In embodiments of the present disclosure, particularly in embodiments where the ophthalmic lens is a spectacle lens, the peripheral zone may have a non-circular outer periphery. The outer periphery of the peripheral zone may be substantially oval, elliptical, or rectangular. The peripheral zone may be surrounded by another non-optically active zone.

[0111] When an integer or element with a known obvious or foreseeable equivalent is mentioned in the foregoing description, such equivalents are incorporated herein as if individually stated. Reference should be made to the claims for determining the true scope of the present disclosure, which should be interpreted as covering any such equivalents. The reader should also understand that 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. In addition, it should be understood that such optional selection of integers or features, although having possible benefits in some embodiments of the present disclosure, may be undesirable and therefore may not exist in other embodiments.

Claims

1. An ophthalmic lens comprising an optical zone centered on an optical axis and a peripheral zone surrounding the optical zone, wherein within the optical zone, along a first meridian, the lens has a first radial curvature refractive measurement curve that continuously changes in a first radial direction from the optical axis to the peripheral zone, and along a second, different meridian, the lens has a second, different radial curvature refractive measurement curve that continuously changes in a second radial direction from the optical axis to the peripheral zone.

2. The ophthalmic lens of claim 1 , wherein the first curvature diopter profile has a first mean radial curvature diopter value measured along the first meridian, and the second radial curvature diopter profile has a second different mean radial curvature diopter value measured along the second meridian. 3 . The ophthalmic lens of claim 2 , wherein the first curvature diopter curve and the second curvature diopter curve have substantially the same shape.

4. An ophthalmic lens according to claim 1, wherein the first curvature refractive power variation curve has a first average radial curvature refractive power value measured along the first meridian, and the second radial curvature refractive power variation curve also has the first average radial curvature refractive power value measured along the second meridian, and wherein the first radial curvature refractive power variation curve has a different shape than the second radial curvature refractive power variation curve.

5. The ophthalmic lens of any preceding claim, wherein at the optical axis, at least one of the first and second radial curvature diopter profiles provides a distance power between +0.5 and -25.0D.

6. The ophthalmic lens of any preceding claim, wherein at the optical axis, at least one of the first and second radial curvature diopter profiles provides a near power between +0.5 and +25.0D.

7. An ophthalmic lens according to any preceding claim, wherein at the optical axis, the first radial curvature refractive diopter variation curve or the second radial curvature refractive diopter variation curve provides distance refractive power, and the other of the first curvature refractive diopter variation curve and the second curvature refractive diopter variation curve provides near refractive power.

8. An ophthalmic lens according to any of the preceding claims of claims 1 to 6, wherein at the optical axis, the first radial curvature refractive measurement curve and the second radial curvature refractive measurement curve have the same value, and at the boundary between the optical zone and the peripheral zone, the first radial curvature refractive measurement curve and the second radial curvature refractive measurement curve have different values.

9. An ophthalmic lens according to any of the preceding claims, wherein one of the first curvature refractive power variation curve and the second curvature refractive power variation curve increases monotonically in radial curvature refractive power as the radial distance from the optical axis increases, and the other of the first curvature refractive power variation curve and the second curvature refractive power variation curve decreases monotonically in radial curvature refractive power as the radial distance from the optical axis increases.

10. An ophthalmic lens according to any preceding claim, wherein one of the first curvature refractive diopter variation curve and the second curvature refractive diopter variation curve comprises at least one peak at a first radial distance from the optical axis of the lens, and the other of the first curvature refractive diopter variation curve and the second curvature refractive diopter variation curve comprises at least one valley at the first radial distance from the optical axis of the lens.

11. An ophthalmic lens according to any preceding claim, wherein the first curvature refractive power variation curve has a peak in radial curvature refractive power at a first radial distance from the optical axis, and the second curvature refractive power variation curve has a peak in radial curvature refractive power at a second, different distance from the optical axis.

12. The ophthalmic lens according to any preceding claim, wherein the first curvature diopter variation curve and / or the second curvature diopter variation curve spans a diopter range of at least 5.0D.

13. An ophthalmic lens according to any preceding claim, wherein a first set of meridians regularly spaced about the optical zone have a first mean radial curvature diopter, and a second set of meridians regularly spaced about the optical zone have a second mean curvature diopter profile.

14. The ophthalmic lens of claim 13, wherein meridians from the first set of meridians form an alternating pattern with meridians from the second set of meridians around the lens.

15. The ophthalmic lens of claim 13 or claim 14, wherein the angular spacing between a meridian from the first set of meridians and an adjacent meridian from the second set of meridians is less than 1°.

16. The ophthalmic lens of any preceding claim, wherein along at least one other meridian in the optical zone, the radial curvature power varies with a third radial diopter variation curve that is different from the second curvature diopter variation curve and the first curvature diopter variation curve.

17. The ophthalmic lens of any preceding claim, wherein each meridian about the optical zone has a peak in radial curvature power at a different radial distance of each meridian from the optical axis.

18. The ophthalmic lens of claim 17, wherein the peak in radial curvature power around the optical zone defines a portion of a spiral.

19. An ophthalmic lens according to any preceding claim, wherein a first set of meridians has the first mean radial curvature diopter and a second set of meridians has a second different mean radial curvature diopter profile, and wherein each meridian in the second set of meridians is orthogonal to a meridian in the first set of meridians.

20. The ophthalmic lens according to any preceding claim, wherein the radial curvature power of the optical zone is derived from the curvature of the front surface of the lens.

21. The ophthalmic lens of any preceding claim, wherein the lens is a contact lens.

22. The ophthalmic lens of any one of claims 1-20, wherein the lens is a spectacle lens.

23. A method of making an ophthalmic lens, wherein the method comprises forming a lens according to any one of claims 1 to 22.

24. A method of designing an ophthalmic lens according to any one of claims 1 to 22, the method comprising: selecting a first mean radial curvature diopter value; selecting a second different mean radial curvature diopter value; Designing a first curvature diopter variation curve for generating the first mean radial curvature diopter value; Designing a second curvature diopter variation curve for generating the second mean radial curvature diopter value; and An optical zone of the lens is designed, wherein the optical zone includes a meridian having the first curvature diopter variation curve and a meridian having the second curvature diopter variation curve.

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