Contact lenses and methods related thereto

Abstract

A contact lens (301) and a method of manufacturing such a lens (301) are described. The glasses (301) comprise an optical zone (302). The optical zone (302) includes a central region (305) having a first optical axis, a center of curvature located on the first optical axis, and a diameter less than 2.0 mm. The optical zone (302) comprises an annular region (303). The annular region (303) comprises a plurality of concentric treatment zones (303a, 303b), where each treatment zone (303a, 303b) has a radial sagittal diopter profile that increases as the radial distance from the optical axis increases.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to contact lenses. The present disclosure relates in particular but not exclusively to contact lenses for slowing the progression of myopia. The present disclosure also relates in particular but not exclusively to contact lenses for use by hyperopic individuals. The present disclosure also relates to methods of manufacturing such lenses. BACKGROUND ART

[0002] Many people, including children and adults, require contact lenses to correct myopia, and many adults may require glasses to correct hyperopia (age-related inability to accommodate and thus focus on near objects).

[0003] Uncorrected myopia focuses incoming light from distant objects to a position in front of the retina. Thus, the light converges towards a plane in front of the retina and diverges towards the retina and is out of focus when it reaches the retina. Conventional glasses for correcting myopia (e.g., spectacle lenses and contact lenses) reduce convergence (for contact lenses) or cause divergence (for spectacle lenses) before the incoming light from distant objects reaches the eye, such that the position of the focus is shifted onto the retina.

[0004] The internal lens of a hyperopic eye does not change shape to increase the diopter required to focus on near objects. Conventional glasses for correcting hyperopia (e.g., spectacle lenses and contact lenses) include an additional positive diopter missing in bifocal or progressive glasses, which include regions optimized for near vision and regions optimized for far vision. Hyperopia can also be treated using bifocal or multifocal glasses or monovision glasses (where different prescriptions are provided for each eye, one eye being provided with glasses for far vision and one eye being provided with glasses for near vision).

[0005] It was proposed decades ago that the progression of myopia in children or young people could be slowed or prevented by undercorrection, i.e., shifting the focus towards but not fully onto the retina. However, this approach necessarily results in degraded far vision compared to the vision obtained with glasses that fully correct myopia. In addition, it is now questioned whether undercorrection effectively controls the progression of myopia. A more recent approach to correcting myopia is to provide glasses that have both one or more regions with full correction for providing far vision and one or more regions with undercorrection or deliberately induced myopic defocus. It has been proposed that this approach can prevent or slow the development or progression of myopia in children or young people while providing good far vision.

[0006] In the case of spectacles having areas that provide defocus, the area that provides full correction of distance vision is typically referred to as the base power area, and the area that provides undercorrection or deliberately induces myopic defocus is typically referred to as the myopic defocus area or the add power area (due to the refractive power correction or less minus power than the distance area). The surface of the add power area (usually the front surface) has a radius of curvature that is less than the radius of curvature of the distance power area and thus provides a more plus or less minus refractive power to the eye. The add power area is designed to focus incoming parallel light (i.e., light from a distance) in front of the retina within the eye (i.e., closer to the spectacles), while the distance power area is designed to focus light and form an image at the retina (i.e., further away from the spectacles).

[0007] A known type of contact lens that reduces myopia progression is the bifocal contact lens available under the name MISIGHT (CooperVision). This bifocal lens differs from bifocal or multifocal contact lenses configured to improve the vision of hyperopic individuals in that the bifocal lens is configured with specific optical dimensions to enable a person who uses distance correction (i.e., base power) to view both distant and near objects. The treatment area of the bifocal lens with add power also provides myopic defocus images at both distant and near viewing distances.

[0008] Although these lenses have been found to be beneficial in preventing or slowing the development or progression of myopia, the annular add power area can cause unwanted vision side effects. Light focused in front of the retina by the annular add power area diverges from the focus to form a defocused ring at the retina. Thus, in some cases, wearers of these lenses may see rings or "halos" around the images formed on the retina, particularly for small bright objects such as streetlights and car headlights. Additionally, in theory, the wearer could use the additional focus in front of the retina caused by the annular add power area to focus on near objects rather than using the natural accommodation of the eye (i.e., the natural ability of the eye to change its focal length) to focus on near objects; in other words, the wearer could inadvertently use the lenses in the same way as glasses for hyperopic correction, which is not desirable for young subjects and could impair their ability to slow myopia progression by removing myopic defocus light.

[0009] Further glasses have been developed for the treatment of myopia and are designed to eliminate the halos observed around the image at the focusing distance. In these glasses, the annular region is configured such that a single on-axis image is not formed in front of the retina, thereby preventing this image from being used to avoid the need for the eye to accommodate to near targets. The fact is that a distant point source is imaged by the annular region into an annular focal line at the near additional diopter focal plane, thus preventing a useful image from being produced at this plane. A second advantage of this type of glasses is that when reaching the retina, the light rays forming the annular image can overlap, resulting in a small spot size on the retina without the surrounding "halo" effect.

[0010] For the treatment of myopia, it should be recognized that providing glasses that introduce additional myopic defocus can be beneficial. For the treatment of hyperopia, providing glasses that produce an extended depth of focus can be beneficial. Summary of the Invention

[0011] According to a first aspect, the present disclosure provides a contact lens comprising an optical zone. The optical zone includes a central region having a first optical axis, a center of curvature located on the first optical axis, and a diameter less than 2.0 mm. The optical zone includes an annular zone, wherein the annular zone includes a plurality of concentric treatment zones. Each treatment zone has a radial sagittal diopter profile that increases as the distance from the optical axis increases.

[0012] According to a second aspect, the present disclosure provides a method of manufacturing glasses. The method may include forming a contact lens. The contact lens comprises an optical zone including a central region having a first optical axis, a center of curvature located on the first optical axis, and a diameter less than 2.0 mm. The optical zone includes an annular region comprising a plurality of treatment zones, wherein each treatment zone has a radial sagittal diopter profile that increases as the radial distance from the optical axis increases.

[0013] Of course, it will be understood 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

[0014] Embodiments of the present disclosure will now be described by way of example only with reference to the accompanying drawings, in which:

[0015] Figure 1A is a top view of a prior art contact lens for preventing myopia;

[0016] Figure 1B is Figure 1A a side view of the contact lens;

[0017] Figure 2A is Figure 1A a ray diagram of the glasses;

[0018] Figure 2B The light pattern formed by a distant point source at the proximal focal plane of the spectacle shown in Figure 1A ;

[0019] Figure 2C The light pattern formed by a distant point source at the telecentric focal plane of the spectacle shown in Figure 1A ;

[0020] Figure 3A is a top view of different contact lenses with non - coaxial optics;

[0021] Figure 3B is Figure 3A a side view of the contact lens shown in

[0022] Figure 4A is Figure 3A and 3B a ray diagram of the spectacle shown in

[0023] Figure 4B The light pattern formed by a distant point source at the proximal focal plane of the spectacle shown in Figure 3A and 3B ;

[0024] Figure 4C The light pattern formed by a distant point source at the telecentric focal plane of the spectacle shown in Figure 3A and 3B ;

[0025] Figure 4D is Figure 3A and 3B a partial ray diagram of the spectacle shown in

[0026] Figure 5A and circles indicating the radius of curvature of the central distance region (solid line) and the annular addition region (dashed line) of the contact lens; Figure 1A and 1B the spectacle shown in Figure 3A and 3B ;

[0027] Figure 5B is a graph showing the sagittal refractive power change of the spectacle shown in Figure 1A and 1B ; Figure 3A and 3B ;

[0028] Figure 6A is a top view of a spectacle according to an embodiment of the present disclosure;

[0029] Figure 6B is Figure 6ASide view of a contact lens;

[0030] Figure 7 is a display of Figure 6A and 6B a graph showing the changes in sagittal refractive power and curvature refractive power of the glasses shown in;

[0031] Figure 8 is Figure 6A and 6B a ray diagram of the glasses of;

[0032] Figure 9A is a top view of the glasses according to an embodiment of the present disclosure;

[0033] Figure 9B is Figure 9A a side view of the contact lens of;

[0034] Figure 10 is a display of Figure 9A and 9B a graph showing the changes in sagittal refractive power and curvature refractive power of the glasses shown in;

[0035] Figure 11 is Figure 9A and 9B a ray diagram of the glasses of;

[0036] Figure 12A is a top view of the glasses according to an embodiment of the present disclosure;

[0037] Figure 12B is Figure 12A a side view of the contact lens of;

[0038] Figure 13 is a display of Figure 12A and 12B a graph showing the changes in sagittal refractive power and curvature refractive power of the glasses shown in;

[0039] Figure 14 is Figure 12A and 12B a ray diagram of the glasses of; and

[0040] Figure 15 is a flowchart showing a method of manufacturing glasses according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0041] According to a first aspect, the present disclosure provides a contact lens. The glasses include an optical zone including a central region having a first optical axis, a center of curvature located on the first optical axis, and a diameter less than 2.0 mm. The optical zone includes an annular zone, wherein the annular zone includes a plurality of concentric treatment zones. Each treatment zone has a radial sagittal refractive power profile that increases as the radial distance from the optical axis increases.

[0042] As used herein, the term contact lens refers to an ophthalmic lens that can be placed on the front surface of the eye. It will be appreciated that this contact lens will provide clinically acceptable movement with the eye and is not incorporated into one or more of a person's eyes. The contact lens can be in the form of a corneal lens (e.g., a lens placed 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 for preventing or slowing the progression or deepening of myopia. The lens can be a lens for providing an extended depth of focus to a hyperopic eye.

[0043] The contact lens according to the present disclosure includes an optical zone. The optical zone encompasses the portion of the lens that has optical functionality. The optical zone is configured to be positioned above the pupil of the eye during use. For the contact lens according to the present disclosure, the optical zone includes a small central region and an annular region surrounding the central region. The optical zone can be surrounded by a peripheral zone. The peripheral zone is not part of the optical zone, but is located outside the optical zone and above the iris when the lens is worn, and it provides mechanical functions, such as increasing the size of the lens, thereby making the lens easier to handle, providing a weight to prevent the lens from rotating, and / or providing a shaping region that improves the comfort of the lens wearer. The peripheral zone can extend to the edge of the contact lens.

[0044] The contact lens according to an embodiment of the present disclosure can include a weight for orienting the lens when positioning the lens on the wearer's eye. When placed on the wearer's eye, the embodiment of the present disclosure incorporating the weight into the contact lens will rotate to a predetermined rest angle under the action of the wearer's eyelid; for example, the weight can be a wedge, and the rotation can be caused by the action of the eyelid on the wedge. Weighted contact lenses are well known in the art for orienting contact lenses; for example, toric contact lenses are weighted to orient the lens so that the orthogonally cylindrical correction provided by the lens correctly aligns with the astigmatism of the wearer's eye.

[0045] The contact lens can be substantially circular in shape and have a diameter of from about 4 mm to about 20 mm. The optical zone can be substantially circular and can have a diameter of from about 2 mm to about 10 mm. In some embodiments, the contact lens has a diameter of 13 mm to 15 mm, and the optical zone has a diameter of 7 mm to 9 mm.

[0046] The first optical axis can be along the center line of the glasses. The first optical axis is defined with reference to a far point light source. Light from a far point light source on the optical axis of the glasses (hereinafter referred to as the on-axis far point light source) will be focused on the optical axis of the glasses. The central region can have a substantially circular shape. The central region can have a substantially oval or elliptical shape. The central region has a small diameter of less than 2.0 mm. The central region can have a diameter of less than 1 mm, less than 0.5 mm, or less than 0.25 mm. If the central region is substantially elliptical or oval in shape, then the maximum diameter can be less than 2.0 mm, less than 1.0 mm, less than 0.5 mm, or less than 0.25 mm.

[0047] The annular region can extend radially outward from the perimeter of the central region. The perimeter of the central region can define the boundary between the central region and the annular region, and thus, the annular region can be adjacent to the central region. The annular region can be a substantially annular region surrounding the optical zone, which can have a substantially circular shape or a substantially elliptical shape, which can completely surround the optical zone, which can partially surround the optical zone.

[0048] The annular region includes a plurality of concentric treatment zones. The annular region can include between 2 and 10 concentric treatment zones, preferably between 4 and 8 concentric treatment zones. Each treatment zone can have a radial width between about 0.1 mm and 2.5 mm, preferably between about 0.2 mm and 1.2 mm, more preferably between about 0.3 mm and 1.0 mm. Each treatment zone can have the same radial width. The treatment zones can have different radial widths.

[0049] Each treatment zone can be directly adjacent to an adjacent treatment zone, i.e., the outer perimeter of the first treatment zone can define the boundary between the first treatment zone and the second treatment zone. Thus, the second treatment zone can be adjacent to the first treatment zone.

[0050] In ophthalmology, the term "sagittal" is used in two different ways, to describe oblique astigmatism and to describe an optical surface.

[0051] In general optics, the term "sagittal" is used when describing oblique astigmatism. Oblique astigmatism occurs when rays from an off-axis position pass through the glasses obliquely. Astigmatism is mainly attributed to the cosine compression that occurs in the meridian along which the rays are emitted. For example, if the rays come from the horizontal peripheral field, the surface (and thus the radius of curvature) will appear cosine-compressed horizontally, resulting in an increase in the diopter (and thus astigmatism) in the meridian. The diopter in the meridian is labeled the "tangential" diopter, while the diopter in the vertical meridian is labeled the "sagittal" diopter. Astigmatism causes a point object to be imaged to two spatially separated and orthogonal line foci, namely the sagittal focal line and the tangential focal line.

[0052] The second use of the term "sagittal" stems from the description of optical surfaces, for example in ophthalmology, where it is crucial for clinical measurements of the anterior eye surface (i.e., in corneal topography). Terms including "sagittal diopter", "tilt diopter", and "axial diopter" are synonyms and can be used interchangeably to describe the diopter of an ophthalmic surface obtained from the position where a ray passing through the surface crosses the optical axis. In the paraxial approximation, the sagittal diopter is equal to the "diopter" of the ophthalmic lens.

[0053] Optical surfaces are usually defined by their radii because the radius is directly related to the diopter (diopter = refractive index difference / radius). For most optical systems, in the paraxial approximation, we consider the surface to have a single radius (i.e., we assume it is part of a sphere), but for the human eye, the anterior corneal surface is far from spherical, so a single radius is insufficient to define this surface because the local radius varies along the surface. Similarly, aspheric ophthalmic lenses (such as contact lenses) have local radii that vary along the ophthalmic surface.

[0054] Due to the aspheric nature of eye and contact lens optics, two radii definitions are used. The radius of curvature of the sagittal of the local surface is the distance to the point where the surface normal intersects the optical axis; using the small angle approximation, this is equal to the distance from the pupil center to the point, and thus the distance from the pupil center is usually used.

[0055] However, for a complete picture of the surface diopter, another radius that should be considered is the local radius of curvature based on the local curvature of the surface. (The sagittal radius is sometimes called the axial radius and the local radius is sometimes called the instantaneous radius.)

[0056] Using the paraxial optical equation (diopter = refractive index difference / radius), the sagittal radius is used to calculate the sagittal diopter and the local radius is used to calculate the curvature diopter (which is also called the local diopter or instantaneous diopter, the latter implying its relationship with the local radius of curvature). Since the sagittal diopter is determined by the slope of the optical surface, it is also called the slope-based diopter.

[0057] As further explained below, when describing an optical wavefront, the sagittal diopter is defined as the slope of the wavefront divided by the radial distance (r) from the optical axis of the ophthalmic lens (usually the center of the lens), i.e., it is related to the first derivative of the wavefront. The (local) curvature diopter is defined by the second derivative of the wavefront.

[0058] For low aberration optics (such as single vision lenses), the sagittal diopter and the curvature diopter can be similar. For a wavefront W, at a point with a normal radial distance r from the center of the wavefront (usually the center of the lens), W(r) = A * r 2 , where A is a function. The curvature diopter is and for a simple spherical lens, it is The sagittal diopter is and for simple spherical glasses is Thus, for simple glasses with spherical wavefronts, under the paraxial approximation, P C = P S .

[0059] However, for some recently developed myopia control glasses that employ "off-axis optics", the values of the slope and curvature diopters can be very different from each other. These glasses have surface regions that focus light from an on-axis source onto regions that are offset from the optical axis, such that the distance that local rays travel to reach the focus can be very different from the distance that they cross the axis. For these types of glasses, the distinction between sagittal (axial) and curvature (local) diopters becomes important. For off-axis optics, the description of the curvature diopter does not provide a complete description of the optics. Adjacent regions of the glasses can have the same fixed curvature diopter, but not the same fixed sagittal diopter (rays from each region cross the axis at different distances from the local focal length and at different distances from each other). For example, for glasses that contain off-axis micro-lenses, the resulting sagittal and curvature diopter values are significantly different. The curvature diopter map of this glass shows a consistent additional diopter for each micro-lens, but the sagittal diopter map shows a sagittal diopter that decreases with increasing radial distance.

[0060] The sagittal diopter is directly related to the ray position at the image plane (the retina plane of the eye) and is thus directly related to image quality. When off-axis optics are implemented, these relationships generally do not exist for the curvature diopter.

[0061] In practice, an example way to measure the wavefront of light passing through an ophthalmic glass is to use an aberrometer, such as a Shack-Hartmann aberrometer. The Shack-Hartmann aberrometer contains a regular array of microlenses. In use, the wavefront to be measured is sampled by a two-dimensional array of microlenses (microlenses), each microlens focusing a different part of the wavefront to a different focus. If the wavefront is planar, then the spatial arrangement of the resulting point spread function will reflect the arrangement of the lenses, and thus the lenses will focus the wavefront to a corresponding regular array of focal spots.

[0062] However, if the wavefront is tilted, then the focal array will be shifted in X and Y, and in the presence of other optical aberrations, the focal array will not replicate the geometry of the microlens array. Instead, parts of the non-planar wavefront will arrive at the lenses at an angle (i.e., not normal incidence), and thus the lenses will focus that part of the wavefront to a focus that is laterally shifted from the position where the wavefront is planar. The magnitude of the lateral shift depends on the average local slope of the part of the wavefront imaged by the lenses relative to the planar wavefront. Thus, the distance of the shifted focal points of the lens array provides a measure of the wavefront slope of the corresponding part of the wavefront.

[0063] The wavefront phase is typically estimated from discrete slope measurements using numerical fitting methods or numerical integration. A more common approach is to fit the slope data with a series of polynomials, which are themselves the differentials of a set of basis functions, namely the Zernike polynomials. The wavefront W(x,y) is represented as a series of k polynomials of order n with coefficients Thus:

[0064]

[0065] Differentiating the expression provides the relationship between the wavefront slope and the differential of the Zernike polynomial:

[0066]

[0067] The coefficients are obtained by fitting the differential Zernike polynomials to the measured wavefront slopes using (2) and (3) The wavefront W(x,y) is thus calculated as a series of Zernike basis functions whose coefficients are obtained by fitting the first derivatives of the basis functions to the measured wavefront slope data.

[0068] The second method (usually applied to data that cannot be fitted with polynomials, e.g., in cases where the refractive power distribution of the spectacle has a sudden local change) uses numerical integration, e.g., by calculating the value of a point from the values of adjacent points and the rate of change of the said value at the adjacent points.

[0069] The effect of a given spectacle on the wavefront is measured by inserting the spectacle into the measurement path at a position optically conjugate to a small spectacle array.

[0070] Thus, the wavefront slope can be measured at intervals across the spectacle, e.g., across the visual zone of a contact lens. For example, a single-pass Shack-Hartmann aberrometer with a (monochromatic, i.e., narrowband) 540 nm light source (e.g (available from www.lumetrics.com obtained)) can be used to measure the wavefront slope every 104 μm across a 10 mm aperture.

[0071] In the real world, the measured wavefront will not be an ideal plane or spherical wavefront. The optical wavefront measurements derived by the aberrometer are typically quantified relative to a standard reference case, which is usually a plane wave or spherical wave expected from the known refractive power of the spectacle under test. The former method results in a wavefront error map that includes all the refractive power and aberrations (low-order and high-order) of the spectacle.

[0072] However, generally, the measured wavefront is known not to be planar even theoretically, for example because it is known to be a diverging or converging wavefront, such as from spectacles with negative or positive diopters respectively. Thus, in an aberrometer, the foci obtained from a converging or diverging wavefront are expected to deviate from a regular array, and the aberration of the spectacles can be separated by subtracting the expected spherical wavefront from the measured wavefront. Specifically, in an aberrometer, the measured offsets of individual spot images will be different from the expected offsets, and the wavefront error is calculated based on these differences. The wavefront error map obtained by subtracting the expected spherical wavefront (due to spectacles with a specific refractive power) from the measured wavefront does not contain the diopter of the spectacles, but may contain low-order (prism, defocus, and astigmatism) and high-order (e.g., coma and spherical aberration) aberrations.

[0073] As described above, numerical fitting or numerical integration methods can be used to calculate the wavefront error map of the pupil from the measured wavefront slopes. The wavefront error map can be corrected for prism (the prism can be removed from the wavefront error data as it disrupts the calculation of the sagittal refractive power).

[0074] In the case where the wavefront error map is oriented such that the principal curvature directions are horizontal (x) and vertical (y), the wavefront error W(x, y) has local horizontal and vertical slopes which can be obtained from the measured wavefront error, for example using numerical differentiation. The sagittal refractive power (i.e., the slope refractive power or the axial refractive power) at each sampling position is here the wavefront error slope divided by the distance r of the sampling position from the center of the spectacles; thus, for example, the radial sagittal refractive power is defined as

[0075]

[0076] where r 2 = x 2 + y 2 .

[0077] The mean curvature refractive power is defined as the local mean curvature of the wavefront error, i.e.,

[0078]

[0079] The Laplace operator averages the local curvatures in all X - Y directions. The Laplace curvature refractive power is defined as twice the mean curvature. The Laplace curvature of a sphere of a given radius will be twice the Laplace curvature of a cylinder of the same radius. (Similarly, the mean curvature of a sphere will be twice the mean curvature of a cylinder.)

[0080] The radial curvature refractive power is defined as:

[0081]

[0082] Similarly, the circumferential (or tangential) curvature power in the direction of the varying angle θ, orthogonal to the radius, is defined as:

[0083]

[0084] For example, consider glasses with a central region having spherical diopter and a toric surface having additional diopter and surrounding the central region, where the toric surface is the surface of a torus, non-spherical, i.e., the additional diopter is focused not on a point on the optical axis but on a ring of off-axis points. In a toric surface, the radial curvature will be greater than the circumferential or tangential curvature. As described above, an aberrometer typically subtracts the spherical diopter of the glasses. The remaining curvature is in the radial direction, passing through the toric surface; the circumferential curvature is flat (since the spherical curvature has been removed). A local x-y differentiator like the Laplacian measures the average change in slope; in the case where the remaining circumferential change in curvature after subtracting the spherical diopter is zero, the measured diopter will thus be half of the radial curvature, and thus the measured curvature diopter derived using the Laplacian is doubled to give the measured radial curvature diopter of the torus.

[0085] In an embodiment of the present disclosure, each treatment region is radially inclined relative to the central region. Accordingly, each treatment region has a radial sagittal diopter profile that increases as the radial distance from the optical axis increases. The radial sagittal diopter profile of the central region may be approximately flat. Alternatively, the radial sagittal diopter profile across the central region may have a curved profile. The radial sagittal diopter profile across the central region may have a quadratic or parabolic shape. As used herein, the inclination of the treatment region means a radial inclination rather than a lateral inclination. Thus, for example, in a radial cross-section of the glasses, the outer end of the arc of the front surface defining the first annular region may be shifted above or below its position in the corresponding non-inclined treatment region. Correspondingly, in three dimensions, the circular perimeter of the treatment region (formed by the ends of the radial arcs) may be shifted above or below its position in the corresponding non-inclined treatment region. In fact, the inclination may be embodied in the optical design of the front surface of the treatment region of the glasses. Alternatively, the inclination may be embodied in the optical design of the rear surface of the treatment region of the glasses, or in the optical designs of both the front surface and the rear surface of the treatment region of the glasses.

[0086] Radially tilting the treatment area relative to the central area shifts the center of curvature of the treatment area away from the optical axis. A greater radial tilt relative to the central area will result in a greater shift of the center of curvature of the treatment area and a steeper gradient of the radial sagittal refractive power profile. Light rays from a distant point source passing through the radially tilted treatment area will not focus towards a single point on the optical axis, but instead towards an off-axis point. For an annular treatment area with a constant radial sagittal refractive power, light rays from a distant point source passing through the radially tilted treatment area will form an annular ring at the focal plane. The diameter of the annular ring will depend in part on the tilt of the treatment area relative to the central area. The diameter of the annular ring will also depend on the radial distance of the treatment area from the optical axis and the radial additional refractive power of the treatment area.

[0087] In glasses having concentric annular regions that provide focusing, light can be considered to be "focused" by the annular regions in two different ways.

[0088] In the first form of focusing, light is focused by the local curvature of the annular region. Considering a transverse 2D cross-section through the glasses, and under the approximation of geometric optics, adjacent light rays from a distant source passing through the radial width of the annular region (i.e., passing through a single "side" of the annulus, i.e., the portion of the radius between the inner perimeter and the outer perimeter of the annular region) are focused to a point by the local curvature of the annular region; and the points from each of the radial widths around the annulus together form a focal ring around the optical axis of the glasses. This local focusing caused by the local curvature within the radial width of the annular region is referred to herein as focusing, and the surface containing the focal ring is referred to as the focal plane. The curvature refractive power of the annular region depends on the degree of (local) focusing.

[0089] In the second form of focusing, light can be focused by the global curvature of one or more annuli combined together. Again considering a transverse 2D cross-section through the glasses, and under the approximation of geometric optics, light rays from a distant source passing through the midpoint of the radial width of the annular region travel in a direction determined by the radial position of the annulus on the glasses and the radial "tilt" of the annular region. The tilt can be selected to ensure that light rays passing through the midpoints of the radial widths on opposite "sides" of the annulus converge to a point on the optical axis. When the glasses contain multiple annuli, light rays passing through the midpoints of the radial widths of all the annuli can converge to the same point. Light rays passing through the entire annulus (not just the midpoint) can converge to a small light spot at this point. To more clearly distinguish it from the first form of focusing, this global focusing caused by the curvature of the glasses and the radial tilt of the annuli is referred to herein as convergence, and the surface containing the point to which the midpoints converge is referred to as the convergence surface. The sagittal refractive power of the annular region depends on the degree of (global) convergence.

[0090] As used herein, the terms focal plane and converging surface do not refer to a physical surface, but rather to a surface upon which a point at which light from a distant object will be focused or reach a locally minimum spot size can be drawn. The eye focuses light onto a curved retina, and in a fully focused eye, the curvature of the surface will match the curvature of the retina, so the eye does not focus light onto a flat mathematical plane. However, in the art, the curved surface of the retina is commonly referred to as a plane.

[0091] In embodiments of the present disclosure, at least two of the treatment zones may have different radial sagittal dioptric profiles. At the boundary between the central zone and the first innermost annular zone, a change in the gradient of the radial sagittal dioptric profile may exist. At the boundary between adjacent treatment zones, a change in the gradient of the radial sagittal diopter may exist. The annular region may include between 2 and 10 concentric treatment zones, preferably between 4 and 8 concentric treatment zones. Each treatment zone may have a different radial sagittal dioptric profile. Alternatively, alternate treatment zones may have the same radial sagittal dioptric profile. The radial sagittal dioptric profile of each treatment zone may have a gradient between about 0.5 D / mm and about 20.0 D / mm, preferably between about 0.5 D / mm and about 10.0 D / mm, more preferably between about 1.0 D / mm and about 5.0 D / mm. The first innermost treatment zone (i.e., closest to the central region) may have a first radial sagittal dioptric profile gradient. The second adjacent treatment zone may have a second different radial sagittal dioptric profile gradient, and the third treatment zone adjacent to the second treatment zone may have the same radial sagittal dioptric profile gradient as the first treatment zone. The first innermost treatment zone (i.e., closest to the central region) may have a first radial sagittal dioptric profile gradient, and the second adjacent treatment zone may have a second greater radial sagittal dioptric profile gradient. The radial sagittal dioptric profile gradient of any or all of the treatment zones may depend on the radial distance of the treatment zone from the first optical axis. Treatment zones at a greater radial distance from the first optical axis may have a greater radial sagittal dioptric profile gradient than treatment zones at a smaller radial distance from the optical axis. Treatment zones at a greater radial distance from the first optical axis may have a greater radial sagittal dioptric profile gradient and a greater radial width compared to treatment zones at a smaller radial distance from the optical axis.

[0092] Tilting the treatment zone radially with respect to the central region changes the radial sagittal dioptric profile of the treatment zone because this is a function of the first derivative of the wavefront, but does not change the radial curvature diopter of the treatment zone, which is a function of the second derivative of the wavefront.

[0093] For glasses according to an embodiment of the present disclosure, the central region may have a substantially flat radial sagittal refractive power profile. The radial sagittal refractive power of the central region will be equal to the radial curvature refractive power of the central region. This may be referred to hereinafter as the base refractive power of the central region. The radial sagittal refractive power across the central region may have a curved profile. The radial sagittal refractive power profile across the central region may have a parabolic or quadratic shape.

[0094] Glasses according to an embodiment of the present disclosure will have a nominal distance refractive power (which is typically the refractive power written on the contact lens packaging). The nominal distance refractive power of the glasses depends on the position of the optimal far focal plane, and this depends on the path of light from a distant point source passing through the treatment area. As discussed above, light from a distant point source passing through the midpoint of the radial width of each treatment area (i.e., midway across the radial width of each treatment area) converges to a point centered on the optical axis and contained within a converging surface. For a first approximation, the optimal far focal plane may be defined as the converging surface where the spot size of the light passing through the radial width of each treatment area is minimized. The position of this optimal far focal plane determines the nominal distance refractive power of the glasses.

[0095] For glasses for treating myopia, the nominal distance refractive power of the glasses will be negative or close to zero. The nominal distance refractive power may be between +0.5 diopters (D) and -15.0 D. The nominal distance refractive power may be between -0.25 D and -15.0 D.

[0096] For glasses according to an embodiment of the present disclosure, the central region may have a base refractive power approximately equal to the nominal distance refractive power. The central region may have a base refractive power less than (i.e., more ametropic or more negative than) the nominal distance refractive power. The central region may have a radial sagittal refractive power that varies with the curved profile. The average radial sagittal refractive power across the central region may be approximately equal to the nominal distance refractive power, or may be less than (i.e., more ametropic or more negative than) the nominal distance refractive power. The average radial sagittal refractive power across the central region may be greater than (i.e., more refractive or less myopic than) the nominal distance refractive power.

[0097] For glasses according to an embodiment of the present disclosure, at least one treatment area may have a radial curvature refractive power greater than the nominal distance refractive power of the glasses. Each treatment area may have a radial curvature refractive power greater than the nominal distance refractive power of the glasses. Thus, each treatment area may provide a radial curvature additional refractive power. Thereafter, the difference between the radial curvature refractive power of each treatment area and the nominal distance refractive power may be referred to as the radial curvature additional refractive power or the curvature additional refractive power.

[0098] Increasing the radius of curvature of the treatment zone will change the radial curvature diopter of the treatment zone, as this is a function of the second derivative of the wavefront. The radial curvature diopter of each treatment zone can be determined by the curvature of at least one surface of the annular region. The radial curvature diopter of each treatment zone can be caused by the curvature of the front surface and / or the back surface of the spectacle. Each treatment zone can have a radius of curvature greater than or less than that of the central region. The front surface of each treatment zone can have a curvature greater than or less than the curvature of the central region. Alternatively or additionally, the back surface of each treatment zone can have a curvature greater than the curvature of the central region.

[0099] The nominal distance diopter of the spectacle can be positive, and each treatment zone can have a curvature diopter more positive than the nominal distance diopter. In this case, light passing through each treatment zone from a distant point source will be focused towards an additional diopter focal plane closer to the spectacle than the far focal plane.

[0100] The nominal distance diopter of the spectacle can be negative, and each treatment zone can have a curvature diopter less negative than the nominal distance diopter, or each treatment zone can have a positive curvature diopter. Considering the spectacle positioned on the cornea, if the curvature diopter of the treatment zone is less negative than the base diopter, then light passing through the treatment zone from a distant point source will be focused towards an additional diopter focal plane further forward in the eye than the far focal plane. Considering the spectacle not positioned on the cornea, if the curvature diopter of the treatment zone is positive, then the additional diopter focal plane will be on the (image) side of the spectacle relative to the far focal plane (which will be a virtual focal plane on the object side of the spectacle); if the curvature diopter of the treatment zone is negative (but less negative than the nominal distance diopter), then the virtual additional diopter focal plane will be further away from the spectacle than the virtual far focal plane.

[0101] For a spectacle according to an embodiment of the present disclosure, the radial curvature diopter of the central region can be equal to or approximately equal to the nominal distance diopter. In this case, when the spectacle is positioned on the eye, light passing through the central region from a distant point source can be focused to a light point on the first optical axis at the far focal plane. Alternatively, the central region can have a radial curvature additional diopter less than the nominal distance diopter. In this case, when the spectacle is positioned on the eye, light passing through the central region from a distant point source can be focused to a light point on the first optical axis closer to the spectacle than the far focal plane.

[0102] The first innermost treatment zone can have a first radial curvature diopter value greater than (i.e., more positive or less negative than) the nominal distance diopter. When the spectacle is positioned on the eye, the first innermost treatment zone can focus light from a distant point source towards a focal plane closer to the spectacle than the far focal plane.

[0103] Each treatment zone may have a different radial curvature addition diopter. The radial curvature diopter of the first innermost treatment zone may have a first value, and the radial curvature diopter of an adjacent second treatment zone located at a greater radial distance from the first optical axis may have a second greater value. This can improve the vision of a spectacle wearer. Alternatively, the second treatment zone located at a greater radial distance from the first optical axis may have a second smaller value. The first innermost treatment zone may have a radial curvature addition diopter between +0.5D and +20.0D, preferably between about +2.0D and +10.0D, more preferably between about +1.0D and +5.0D. The second adjacent treatment zone may have a greater radial curvature addition diopter between +0.5D and +20.0D, preferably between +4.0D and +20.0D. The radial curvature addition diopter of the treatment zones may alternate between a high radial curvature addition diopter value and a low radial curvature addition diopter value, the high radial curvature diopter being greater than the nominal distance diopter of the spectacle. Both the high radial curvature addition diopter value and the low radial curvature addition diopter value may be greater than the nominal distance diopter of the spectacle. The high radial curvature addition diopter may be between +4.0D and +20.0D. The low radial curvature addition diopter may be between +1.0D and +5.0D. For spectacles on an eye, the high radial curvature addition diopter treatment zone focuses light from a distant point source towards a proximal focal plane closer to the spectacle than the far focal plane. The low radial curvature addition diopter treatment zone may focus light from a distant point source towards an intermediate focal plane located between the proximal focal plane and the far focal plane.

[0104] Alternatively, each treatment zone may have the same radial curvature addition diopter. The radial curvature addition diopter of each treatment zone may be greater than the nominal distance diopter.

[0105] At the boundary between adjacent treatment zones, depending on the relative radial curvature addition diopters of the treatment zones, there may be a sharp, discontinuous increase or decrease in the radial curvature diopter.

[0106] At the boundary between adjacent treatment zones, there may be a sharp, discontinuous increase or decrease in the radial sagittal diopter. At the midpoint across the radial width of the first innermost treatment zone, the radial sagittal diopter may match the nominal distance diopter of the spectacle. At the midpoint across the radial width of any or all of the treatment zones, the radial sagittal diopter may match the nominal distance diopter of the spectacle.

[0107] At the midpoint across the width of each treatment zone, the radial sagittal diopter may be the same.

[0108] At any boundary between adjacent treatment zones, there may be a sharp increase in the radial sagittal diopter. The radial sagittal diopter at the midpoint across the radial width of each treatment zone will be less than the radial curvature diopter of the treatment zone. At least one treatment zone may be a sagittal addition treatment zone having a radial sagittal diopter greater than the nominal distance diopter of the spectacle across the width of the treatment zone. For each treatment zone, the radial curvature diopter may be greater than the radial sagittal diopter across the width of the treatment zone. The sagittal addition treatment zone is radially tilted in such a way that the radial sagittal diopter is greater than the nominal distance diopter of the spectacle across the width of the treatment zone. The radial sagittal diopter across the width of the sagittal addition treatment zone will be less than that of a coaxial or on-axis treatment zone having the same radial curvature addition diopter. For these treatment zones, light from a distant point source passing through the radial midpoint of the treatment zone will be focused towards the sagittal addition diopter focal plane. For a spectacle on the eye, the sagittal addition diopter focal plane will be closer to the spectacle than the far focal plane of the spectacle.

[0109] Contact lenses can include an elastomeric material, a polysiloxane elastomeric material, a hydrogel material, a polysiloxane hydrogel material, or a combination thereof. As understood in the field of contact lenses, a hydrogel is a material that retains water in equilibrium and does not have a polysiloxane-containing chemical. A polysiloxane hydrogel is a hydrogel that contains a polysiloxane-containing chemical. As described in the context of the present disclosure, hydrogel materials and polysiloxane hydrogel materials have an equilibrium water content (EWC) of at least 10% to about 90% (wt / wt). In some embodiments, the hydrogel material or the polysiloxane hydrogel material has an EWC of about 30% to about 70% (wt / wt). In contrast, as described in the context of the present disclosure, polysiloxane elastomeric materials have a water content of about 0% to less than 10% (wt / wt). Generally, the polysiloxane elastomeric materials used with the present method or device have a water content of 0.1% to 3% (wt / wt). Examples of contact lens formulations suitable for glasses include contact lens formulations 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, 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.

[0110] Alternatively, the contact lenses can include a polysiloxane elastomeric material, consist essentially of a polysiloxane elastomeric material, or consist of a polysiloxane elastomeric material. For example, the contact lenses can include a polysiloxane elastomeric material having a Shore A hardness of 3 to 50, consist essentially of a polysiloxane elastomeric material having a Shore A hardness of 3 to 50, or consist of a polysiloxane elastomeric material having a Shore A hardness of 3 to 50. The Shore A hardness can be determined using conventional methods as understood by those of ordinary skill in the art (e.g., using Method DIN 53505). Other polysiloxane elastomeric materials can be obtained, for example, from NuSil Technology or Dow Chemical Company.

[0111] According to a second aspect, the present disclosure provides a method of manufacturing glasses. The method may include forming a contact lens. The contact lens includes an optical zone including a central region having a first optical axis, a base radial sagittal refractive power, a center of curvature located on the first optical axis, and a diameter less than 2.0 mm. The optical zone includes an annular region including a plurality of treatment zones, wherein each treatment zone has a radial sagittal refractive power profile that increases with an increasing radial distance from the optical axis.

[0112] The glasses may include any of the features described above with respect to the first aspect of the present disclosure.

[0113] The manufacturing method may include forming a master mold member having a concave lens forming surface and a male mold member having a convex lens forming surface. The method may include filling a gap between the master mold member and the male mold member with a bulk lens material. The method may further include curing the bulk lens material to form the glasses.

[0114] The contact lens may be formed using a lathe machining process. The glasses may be formed by a casting molding process, a rotational casting molding process, or a lathe machining process or a combination thereof. As understood by those skilled in the art, casting molding refers to molding the glasses by placing a lens forming material between a master mold member having a concave lens member forming surface and a male mold member having a convex lens member forming surface.

[0115] Figure 1A Schematic top view showing prior art glasses for slowing down myopia progression (e.g., myopia control). Figure 1B Showing Figure 1A Schematic cross-sectional side view of the glasses. Glasses 1 include an optical zone 2 that generally covers the pupil and a peripheral zone 4 located above the iris. The peripheral zone 4 provides mechanical functions, including increasing the size of the glasses, thereby making the glasses 1 easier to handle, providing a pendant weight to prevent the glasses 1 from rotating, and providing a shaping area that improves the comfort of the wearer of the glasses 1. The optical zone 2 provides the optical functionality of the glasses 1, and the optical zone 2 includes an annular region 3 and a central region 5. For these glasses 1, the central region 5 has a base curvature refractive power corresponding to the distance refractive power of the glasses 1. The annular region 3 has a radial curvature refractive power greater than the base curvature refractive power of the central region 5. Figure 2A is a schematic ray diagram showing how the glasses focus light when Figures 1A to 1B the glasses 1 are positioned on the eye. The focus 11 of the annular region 3 is located on the proximal focal plane 13, and the focus 15 of the central region 5 is located on the distal focal plane 17, which is further away from the rear surface of the glasses 1. The focus 11 of the annular region 3 and the focus 15 of the central region 5 share a common optical axis 19. As Figure 2A and 2CAs shown in, for a point source at infinity, the light rays focused by the central region 5 form a focused image 23 at the remote focal plane 17. As Figure 2A and 2B shown in, the light rays focused by the central region 5 also produce an unfocused blurred light spot 27 at the proximal focal plane 13.

[0116] As Figure 2A and 2B shown in, the light rays focused by the annular region 3 form a focused on-axis image 21 at the proximal focal plane 13. The light rays focused by the annular region 3 diverge behind the proximal focal plane 13, and as Figure 2A and 2C shown in, the diverging light rays produce an unfocused annulus 25 at the remote focal plane 17. As discussed above, the unfocused annulus 25 image can cause the wearer of the glasses to see a "halo" around the focused distance image. Figures 1A to 2C The annular region 3 of the glasses 1 can be referred to as a coaxial annular region 3 because the light rays from a distant point source passing through the annular region 3 are focused onto a light spot on the optical axis 19.

[0117] Figure 3A and 3B show a schematic top view of another known pair of glasses 101. Similar to Figure 1A and 1B the glasses 1 shown in, the glasses 101 include an optical zone 102 and a peripheral zone 104 surrounding the optical zone 102. The optical zone 102 includes a central region 105 and a first annular region 103 surrounding the central region 105. As Figure 4A and 4D shown in, the central region 105 has a center of curvature located on the optical axis 119. The first annular region 103 is radially inclined with respect to the central region 105, and the first annular region 103 has an off-axis center of curvature at a first distance from the optical axis 119. The front surface of the first annular region 103 has a greater curvature than the front surface of the central region 105, and thus provides a curvature diopter greater than the base curvature diopter of the central region 105. Figure 4D is a partial ray diagram of the glasses 101 when Figures 3A to 3B the glasses 101 are positioned on the glasses and circles indicating the radii of curvature of the central distance region (solid circle) and the annular addition region (dashed circle) of the glasses 101. As Figure 4D shown in, the front surface of the central region 105 defines a portion of the surface of a sphere having a larger radius 109. The front surface of the annular region 103 defines a curved annular surface having a smaller radius 106.

[0118] Figure 4A and 4C show when Figures 3A to 3BThe light pattern formed by a distant point source at the telecentric focal plane 117 of the glasses 101 when the glasses are positioned on the eyes. At the telecentric focal plane 117, the light rays passing through the central region 105 are focused. The light rays passing through the midpoint of the width of the annular region 103 converge at the same point where the light rays passing through the central region 105 are focused. The annular region 103 acts as a light beam stop, which results in a small light spot 133 of light at the telecentric focal plane 117.

[0119] Figure 4B Shows the light pattern formed by a distant point source at the proximal focal plane 113 of the glasses 101 when the glasses 101 are positioned on the eyes. A single image is not formed at the proximal focal plane 113. At the proximal focal plane 113, for a point source at infinity, the light rays passing through the central region 105 produce a blur circle 128. However, the light rays passing through the annular region 103 from a distant point source produce an annular ring 122, as shown in Figures 3A to 3B which surrounds the blur circle 128. Figure 4B as shown in Figure 4B Shows the light pattern produced for a distant point source.

[0120] Compared with Figure 1A and 1B the glasses 1 of Figure 2A and 2B the glasses 101 do not produce a single image or an on-axis image at the proximal focal plane 113, which can be used to avoid the need for the eyes to accommodate to nearby objects. For a distant extended object, the image formed at the proximal focal plane 113 is the convolution of (i) the focused image of the extended object obtained with conventional glasses having an optical diopter with an annular region and (ii) the optical transfer function representing the optical effect of the annular region 103.

[0121] Compared with Figure 1A and 1B the prior art glasses of Figures 3A to 3B the annular region 103 of the glasses 101 can be referred to as a non-coaxial annular region 103 or an off-axis annular region 103 because the light rays passing through the annular region 103 from a distant point source are not focused at a light spot on the optical axis 119.

[0122] Figure 5A Shows a comparison between the radial sagittal diopter profile 231 (dashed line) of glasses having two coaxial or on-axis additional diopter annular regions (i.e., annular regions that focus the light from a distant point source towards a light spot on the optical axis) with a width of 203, 203' and the radial sagittal diopter profile 233 (solid line) of glasses having two non-coaxial or off-axis additional diopter annular regions (i.e., annular regions that do not focus the light towards a light spot on the optical axis) with a width of 203, 203'. Figure 5BA corresponding comparison of the radial curvature profile 232 (dashed line) of an eyeglass having two coaxial addition diopter annular regions spanning widths 203 and 203' and the radial curvature diopter profile 234 (solid line) of an eyeglass having two non - coaxial addition diopter annular regions spanning widths 203, 203' is shown. The radial sagittal diopter and the radial curvature diopter in diopters (D) are plotted as varying with the radial distance from the center (r = 0) of the eyeglass. Both eyeglasses have a flat radial sagittal profile and a radial curvature diopter across the central region 205. At the boundary between the central region 205 and the first annular region 203, for the on - axis or coaxial eyeglass, there is a sharp increase in the radial sagittal diopter 231 and a sharp increase in the radial curvature diopter 232; the radial sagittal diopter profile 231 and the radial curvature diopter profile 232 are constant across the width of the annular region 203. At the boundary between the central region 205 and the annular region 203, for the non - coaxial eyeglass, there is a sharp increase in the radial curvature diopter 234, but a sharp decrease in the radial sagittal diopter 233. Due to the radial tilt of the annular region relative to the central region, for the non - coaxial eyeglass, the radial sagittal diopter 233 increases with a constant gradient across the radial width of the annular region 203. For the non - coaxial eyeglass, at the mid - point across the width of the annular region 203, the radial sagittal diopter 233 matches the radial sagittal diopter 233 across the central region 205, which in this case corresponds to the distance diopter of the eyeglass. Both eyeglasses have a second annular region located at a greater radial distance from the center of the eyeglass. Both eyeglasses have the same radial curvature diopters 232, 234 across the two annular regions 203, 203'. For the coaxial eyeglass, the radial sagittal diopter 231 across the width 203' of the second annular region is substantially the same as the radial sagittal diopter 231 across the first annular region 203. For the non - coaxial eyeglass, a smaller radial sagittal addition diopter is required to achieve the same radial curvature diopter, and thus the gradient of the radial sagittal diopter profile 233 across the second annular region 203' is less than the gradient across the first annular region 203. Both eyeglasses have a distance diopter region 207 having a substantially flat radial sagittal diopter profile 231, 233 and a substantially flat radial curvature diopter profile 232, 234 between the first 203 and second 203' annular regions. The radial curvature diopters 232, 234 across the distance diopter region 207 match the radial curvature diopters 232, 234 across the central region 205.

[0123] Figure 6A A schematic top - view of an eyeglass 301 according to an embodiment of the present disclosure is shown. Figure 6B Show Figure 6ASchematic cross-sectional view of glasses 301. The glasses 301 include an optical zone 302 that generally covers the pupil and a peripheral zone 304 located above the iris. The peripheral zone 304 provides mechanical functions, including increasing the size of the glasses, thereby making the glasses 301 easier to handle, providing a pendant weight to prevent the glasses 301 from rotating, and providing a shaping area that improves the comfort of the wearer of the glasses 301. The optical zone 302 provides the optical functionality of the glasses 301. The optical zone 302 includes a small central area 305 having a diameter of 0.5 mm and an annular area 303 surrounding the central area 305. The annular area 303 includes two concentric treatment zones 303a, 303b. Each treatment zone 303a, 303b is radially inclined with respect to the central zone 305. Each treatment zone 303a, 303b provides a radially curved additional diopter. For these glasses 301, the radially curved additional diopter is caused by the greater curvature of the front surface of the glasses 301. The inner treatment zone 303a has a low radially curved additional diopter, and the outer treatment zone 303b has a high radially curved additional diopter.

[0124] Figure 7 Shows the radial sagittal diopter profile 331 and the radial curvature diopter profile 332 taken along Figure 6A and 6B the radial diameter of the glasses 301 shown in. Across the width of the central area 305, the radial sagittal diopter profile 331 is flat. Across the width of the central area 305, the radial sagittal diopter 331 is equal to the radial curvature diopter 332. For Figure 6A and 6B the glasses 601, the radial sagittal diopter 331 and the radial curvature diopter 332 across the central area 305 are more negative than the nominal distance diopter of the glasses (indicated by the dashed line 330).

[0125] At the boundary between the central zone 305 and the inner treatment zone 303a, there is an increase in the radial curvature diopter 332. The inner treatment zone 303a has a greater curvature than the central zone 305 and thus provides a radially additional curvature diopter. The radial curvature diopter 332 is approximately constant across the width of the inner treatment zone 303a. At the boundary between the inner treatment zone 303a and the outer treatment zone 303b, there is another sharp increase in the radial curvature diopter 332. The outer treatment zone 303b has a greater curvature than the innermost treatment zone 303a and provides a greater radially curved additional diopter.

[0126] Across the inner treatment zone 303a, the radial sagittal diopter 331 increases with a constant positive gradient. At the midpoint of the radial width across each treatment zone 303a, 303b, the radial sagittal diopter 331 matches the nominal distance diopter of the glasses 303. The gradient of the radial sagittal diopter profile 331 across the outer treatment zone 303b is greater than the gradient across the inner treatment zone 303a.

[0127] Figure 8 Is to show Figure 6A and 6B Schematic partial ray diagram (not to scale) of how the treatment zones 303a, 303b of the eyeglass 301 focus light when the eyeglass 301 is positioned on the eye. Light from a distant point source passing through the small central area 305 is focused toward a spot on the optical axis 319 at the central zone focal plane 318. The inner treatment zone 303a and the outer treatment zone 303b are both radially inclined relative to the central zone 305, and therefore light from distant point sources passing through the treatment zones 303a, 303b is not focused toward a single spot on the optical axis 319. Light rays from distant point sources passing through the radial midpoint of each treatment zone 303a, 303b converge at a converging surface 317 that intersects the optical axis 319, and the converging surface 317 is positioned behind the eyeglass 301 when the eyeglass 301 is positioned on the eye. This converging surface 317 is the optimal long-range focal plane and determines, to a first approximation, the nominal distance power of the eyeglass 301. For Figures 6A to 6B In the eyeglasses 301 , the nominal distance diopter is greater than the radial curvature diopter of the central zone 305 , and therefore the optimal remote focal plane is located in front of the eye compared to the central zone focal plane 318 .

[0128] against Figure 6A and 6B , each treatment zone 303a, 303b has a radial curvature diopter that is greater than the nominal distance diopter and radial curvature diopter of the central zone 305. Thus, light from a distant point source passing through the treatment zones 303a, 303b is focused toward surfaces 341, 343 that are located in front of the eye compared to the nominal distance focal plane 317 and the central zone focal plane 318. The radial curvature diopter profile is approximately constant across the width of each treatment zone 303a, 303b.

[0129] The innermost radial treatment zone 303a has a low radial curvature add power. Therefore, the focal plane 341 of light rays from distant point sources passing through this treatment zone 303a is shifted closer to the eyeglass 301 than the remote focal plane 317. This inner treatment zone 303a is radially tilted relative to the central zone 305, and therefore, light rays from distant point sources passing through this treatment zone 303a are not focused toward a single spot on the optical axis 319. Instead, light rays from distant point sources passing through the innermost treatment zone 303a form an annular ring 337 at the low add focal plane 341.

[0130] The outer treatment zone 303b, which is located adjacent to the inner treatment zone 303a at a relatively large radial distance from the optical axis 319, has a high radial curvature addition power that is greater than the radial curvature addition power of the inner treatment zone 303a. Accordingly, this outer treatment zone 303b focuses light from a distant point source towards a high addition focal plane 343 that is closer to the spectacle 301 compared to the telecentric focal plane 317 and the low addition focal plane 341. The outer treatment zone 303b is also tilted relative to the central zone 305, and thus light passing through the second treatment zone 303b from a distant point source is not focused towards a point on the optical axis 319, but instead forms an annular ring 339 at the high addition focal plane 343.

[0131] Figure 9A FIG. shows a schematic top view of a spectacle 401 according to another embodiment of the present disclosure. Figure 9B FIG. shows Figure 9A a schematic cross-sectional view of the spectacle. The spectacle 401 includes an optical zone 402 that generally covers the pupil and a peripheral zone 404 that is located above the iris. The peripheral zone 404 provides mechanical functions, including increasing the size of the spectacle 401, thereby making the spectacle 401 easier to handle, providing a pendant weight to prevent the spectacle 401 from rotating, and providing a contoured area that improves the comfort of the wearer of the spectacle 401. The optical zone 402 provides the optical functionality of the spectacle 401. The optical zone 402 includes a small central area 405 having a diameter of 0.5 mm and an annular area 403 that surrounds the central area 405. The annular area 403 includes two concentric treatment zones 403a, 403b. The two treatment zones 403a, 403b are radially tilted relative to the central zone 405. The two treatment zones 403a, 403b have a radial curvature power that is greater than the radial curvature power of the central zone 405 and greater than the nominal distance power of the spectacle 401. For this spectacle 401, each treatment zone 403a, 403b provides the same radial curvature addition power relative to the central area 405.

[0132] Figure 10 FIG. shows a radial sagittal power profile 431 and a radial curvature power profile 432 taken along the Figure 9A and 9B radial diameter of the spectacle 401 shown in FIG. Across the width of the central area 405, the radial sagittal power profile 431 and the radial curvature profile 432 are flat. Across the width of the central area 405, the radial sagittal power 431 is equal to the radial curvature power 432, and this may hereinafter be referred to as the base power. For the Figure 9A and 9B spectacle 401, the base power is equal to the nominal distance power of the spectacle (indicated by the dashed line 430).

[0133] At the boundary between the central zone 405 and the inner treatment zone 403a, there is a sharp increase in the radial curvature diopter 432. The inner treatment zone 403a has a greater curvature than the central zone 405 and thus provides a radial additional curvature diopter. The radial curvature diopter 432 is constant across the width of the innermost treatment zone 403a. At the boundary between the inner treatment zone 403a and the outer treatment zone 403b, there is no change in the radial curvature diopter 432. The outer treatment zone 403b has the same radial curvature additional diopter as the inner treatment zone 403a.

[0134] At the boundary between the central zone 405 and the inner treatment zone 403a, there is a sharp decrease in the radial sagittal diopter 431, and across the inner treatment zone 403a, the radial sagittal diopter 431 increases with a constant positive gradient. At the boundary between the inner treatment zone 403a and the outer treatment zone 403b, there is another sharp decrease in the radial sagittal diopter 431. The gradient of the radial sagittal diopter profile 431 is small across the outer treatment zone 403b because at a greater radial distance from the optical axis, a smaller radial sagittal diopter is required to produce the same radial curvature diopter.

[0135] Figure 11 Is a schematic partial ray diagram (not to scale) showing how the treatment zones 403a, 403b of the spectacle 401 focus light when Figure 9A and 9B the spectacle 401 is positioned on the eye. Light passing through the small central region 405 from a distant point source is focused towards a light point on the optical axis 419 at the central zone focal plane 418. Both the inner treatment zone 403a and the outer treatment zone 403b are radially inclined with respect to the central zone 405, and thus light passing through the treatment zones 403a, 403b from a distant point source is not focused towards a single light point on the optical axis 419. Rays passing through the radial midpoints of each treatment zone 403a, 403b from a distant point source converge at a converging surface 417 that intersects the optical axis 419, and when the spectacle 401 is positioned on the eye, the converging surface 417 is positioned behind the spectacle 401. This converging surface 417 is the best far - field focal plane and determines the nominal distance diopter of the spectacle 401 to a first approximation. For Figures 9A to 9B the spectacle 401, the best far - field focal plane coincides with the central zone focal plane 418.

[0136] For Figure 9A and 9B the spectacle 401 shown in, the two treatment zones 403a, 403b have the same radial curvature additional diopter. Due to the radial curvature additional diopter, light passing through the treatment zone 403a or the treatment zone 403b from a distant point source is focused at an additional diopter focal plane 441 closer to the spectacle 401 than the far - field focal plane 417.

[0137] This innermost treatment zone 403a is radially inclined with respect to the central zone 405, and thus, light rays passing through this treatment zone 403a from a distant point source are not focused towards a single spot on the optical axis 419. Instead, as Figure 11 shown in

[0138] the light rays passing through the innermost treatment zone 403a from a distant point source form an annular ring 437 at the additional dioptric focal plane 441. The outer treatment zone 403b is also inclined with respect to the central zone 405 and with respect to the inner treatment zone. Light passing through the outer treatment zone 403b from a distant point source is not focused towards a spot on the optical axis 419, but instead forms an annular ring 439 at the additional dioptric focal plane 441. Since the outer treatment zone 403b is located at a greater radial distance from the optical axis compared to the inner treatment zone 403a, and since the relative radial inclinations of the inner treatment zone 403a and the outer treatment zone 403b are different, the diameter of the annular ring 439 formed by the light passing through the outer treatment zone 403b is greater than the diameter of the annular ring 437 formed by the light passing through the inner treatment zone 403a.

[0139] Figure 12A FIG. shows a schematic top view of glasses 501 for slowing myopia progression (e.g., myopia control) according to another embodiment of the present disclosure. Figure 12B FIG. shows Figure 12A a schematic cross-sectional view of the glasses 501. The glasses 501 include an optical zone 502 that generally covers the pupil and a peripheral zone 504 located above the iris. The peripheral zone 504 provides mechanical functions, including increasing the size of the glasses, thereby making the glasses 501 easier to handle, providing a pendant weight to prevent the glasses 501 from rotating, and providing a contoured area that improves the comfort of the wearer of the glasses 501. The optical zone 502 provides the optical functionality of the glasses 501. The optical zone 502 includes a small central area 505 having a diameter of 0.5 mm and an annular area 503 surrounding the central area 505. The annular area 503 includes two concentric treatment zones 503a, 503b. The two treatment zones 503a, 503b are radially inclined with respect to the central zone 505, and the two treatment zones 503a, 503b provide a radial curvature addition diopter with respect to the central area 505 and with respect to the nominal distance diopter of the glasses 505.

[0140] Figure 13 FIG. shows the radial sagittal diopter profile 531 and the radial curvature diopter profile 532 taken along the Figure 12A radial diameter of the glasses 501 shown in 12B and Figure 12A FIG. 12BThe glasses 501 have a radial sagittal refractive power 531 and a radial curvature refractive power 532 across the central region 505 that are more negative than the nominal distance refractive power of the glasses (indicated by the dashed line 530).

[0141] Both treatment zones 503a, 503b have a radial curvature refractive power 532 greater than the nominal distance refractive power. At the boundary between the central zone 505 and the inner treatment zone 503a, there is a sharp increase in the radial curvature refractive power profile 532. The inner treatment zone 503a has a curvature greater than that of the central zone 505 and the nominal distance refractive power of the glasses 501, and thus provides a radial additional curvature refractive power. The radial curvature refractive power 532 is constant across the width of the innermost treatment zone 503a. At the boundary between the inner treatment zone 503a and the outer treatment zone 503b, there is a further increase in the radial curvature refractive power 532. The outer treatment zone 503b has a greater radial curvature additional refractive power than the inner treatment zone 503a.

[0142] Across the innermost treatment zone 503a, the radial sagittal refractive power 531 increases with a constant positive gradient. The outer treatment zone 503b is tilted relative to the central region 505 and the inner treatment zone 503a, and the radial sagittal refractive power 531 across the width of the outer treatment zone 503 is greater than the radial sagittal refractive power 531 across the width of the inner treatment zone 503a. Across the width of the outer treatment zone 503b, the radial sagittal refractive power 531 increases with a constant gradient. Across the width of the outer treatment zone 503b, the radial curvature refractive power 532 of the outer treatment zone is greater than the radial sagittal refractive power 531.

[0143] Figure 14 is a schematic partial ray diagram (not to scale) showing how the treatment zones 503a, 503b of the glasses 501 focus light when Figure 12A and 12B the glasses 501 are positioned on the eye. Light passing through the small central region 505 from a distant point source is focused towards a light point on the optical axis 519 at the central zone focal plane 518. Both the inner treatment zone 503a and the outer treatment zone 503b are radially tilted relative to the central zone 505, and thus light passing through the treatment zones 503a, 503b from a distant point source is not focused towards a single light point on the optical axis 519. Rays passing through the radial midpoints of the treatment zones 503a, 503b from a distant point source converge at a converging surface 517 that intersects the optical axis 519, and when the glasses 501 are positioned on the eye, the converging surface 517 is located behind the glasses 501. The converging surface 517 is the optimal far focal plane and determines the nominal distance refractive power of the glasses 501 to a first approximation. For Figures 12A to 12B the glasses 501, the nominal distance refractive power is less negative than the radial curvature refractive power of the central region 505, and thus the optimal far focal plane 517 is closer to the glasses 501 than the central zone focal plane 518.

[0144] For Figure 12A and 12B the spectacle 501 shown in Figure 12A and 12B , the inner treatment zone 503a has a nominal distance dioptric power and a radial curvature dioptric power greater than that of the central zone 505 but less than the radial curvature dioptric power of the outer treatment zone 503b. Thus, light passing through the inner treatment zone 503a from a distant point source is focused towards a low addition dioptric power focal plane 541 closer to the spectacle 501 than the telecentric focal plane 517 and the central zone focal plane 518. The inner treatment zone 503a is radially inclined with respect to the central zone 505, and thus light passing through the inner treatment zone 503a from a distant point source forms an annular ring 537 at the low addition dioptric power focal plane 541. The outer treatment zone 503b is inclined with respect to the central zone 505 and the inner treatment zone 503a, and the outer treatment zone 503b has a radial sagittal dioptric power across its width greater than the radial sagittal dioptric power across the inner treatment zone 503a. Light rays passing through the radial midpoint of the outer treatment zone 503b (i.e., the midpoint across the radial width of the outer treatment zone 503b) from a distant point source converge at a point 544 on the optical axis at the sagittal addition dioptric power converging surface 545. Light rays passing through the outer treatment zone 503b from a distant point source are focused towards a high addition dioptric power focal plane 543 closer to the spectacle 501 than the low addition dioptric power focal plane 541, the telecentric focal plane 517, and the central zone focal plane 518. The outer treatment zone 503b is radially inclined with respect to the central zone 505, and thus light passing through the outer treatment zone 503b from a distant point source forms an annular ring 539 at the high addition dioptric power focal plane 541.

[0145] Figure 15 is a flowchart showing a method 660 of manufacturing a contact lens according to an embodiment of the present disclosure. The contact lens includes an optical zone including a central region having a first optical axis, a base radial sagittal dioptric power, a center of curvature located on the first optical axis, and a radial diameter less than 0.5 mm. The optical zone includes an annular region including a plurality of treatment zones, wherein each treatment zone has a radial sagittal dioptric power profile that increases with an increase in the radial distance from the optical axis. The spectacle may include any of the features stated above. In a first step 661, the method includes forming a master mold member having a concave spectacle forming surface and a male mold member having a convex spectacle forming surface. In a second step 663, the method includes filling the gap between the master mold member and the male mold member with a bulk spectacle material. In a third step 665, the method includes curing the bulk spectacle material to form the spectacle.

[0146] In an alternative embodiment of the present disclosure, a lathe machining process, a casting molding process, a rotational casting molding process, or several lathe machining processes or a combination thereof may be used to form the spectacle.

[0147] 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.

[0148] In the example embodiments of the present disclosure described above Figures 6A to 14 the contact lens includes two concentric treatment zones. In other embodiments, the contact lens may include more than two concentric treatment zones. For example, the contact lens may include between two and ten concentric treatment zones. In the example embodiments of the present disclosure described above Figures 6A to 14 the treatment zones have approximately the same radial width. In other embodiments, the treatment zones may have different radial widths.

[0149] In embodiments of the present disclosure, the coaxial and non-coaxial regions of the contact lens may have the same curvature diopter. In other embodiments, the coaxial and non-coaxial regions of the contact lens may have different curvature diopters.

[0150] Although integers or elements with known obvious or foreseeable equivalents have been mentioned in the foregoing description, such equivalents are incorporated herein as if individually set forth. Reference should be made to the claims to determine the true scope of the present disclosure, which should be construed to cover any such equivalents. The reader will also appreciate that the 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. Additionally, it should be understood that although such optional integers or features may be beneficial in some embodiments of the present disclosure, they may not be desired and thus may not be present in other embodiments.

Claims

1. A contact lens, the lens comprising an optical zone, the optical zone comprising: a central region having a first optical axis, a center of curvature located on the first optical axis, and a diameter of less than 2.0 mm; and an annular region including a plurality of concentric treatment zones, wherein each treatment zone has a radial sagittal refractive power profile that increases with an increasing radial distance from the optical axis.

2. The contact lens according to claim 1, wherein at least two of the treatment zones have different radial sagittal refractive power profiles.

3. The contact lens according to claim 1 or claim 2, wherein the annular zone includes between 2 and 10 concentric treatment zones.

4. The contact lens according to any one of the preceding claims, wherein each of the plurality of concentric treatment zones has a different radial sagittal refractive power profile.

5. The contact lens according to any one of the preceding claims, wherein each treatment zone has a radial width between about 0.1 mm and 2.5 mm.

6. The contact lens according to any one of the preceding claims, wherein each treatment zone has a radial sagittal refractive power gradient between about 0.5 D / mm and about 20.0 D / mm.

7. The contact lens according to any one of the preceding claims, having a nominal distance refractive power between +0.5 D and -15.0 D.

8. The contact lens according to claim 7, wherein at least one treatment zone has a radial curvature refractive power greater than the nominal distance refractive power of the lens.

9. The contact lens according to claim 7, wherein each treatment zone has a radial curvature refractive power greater than the nominal distance refractive power of the lens.

10. The contact lens according to any one of the preceding claims, wherein the radial curvature refractive power of the central region is equal to the nominal distance refractive power.

11. The contact lens according to any one of claims 1 to 9, wherein the nominal distance refractive power of the lens is greater than the radial curvature refractive power of the central region.

12. The contact lens according to any one of claims 7 to 8 or claims 10 to 11, wherein alternating concentric treatment zones provide a higher radial curvature refractive power and a lower radial curvature refractive power, wherein the higher radial curvature refractive power is greater than the nominal distance refractive power of the lens.

13. The contact lens according to claim 12, wherein the lower radial curvature additional refractive power is greater than the nominal distance refractive power of the lens.

14. The contact lens according to any one of claims 7 to 10 or claim 12, wherein each treatment zone provides a radial curvature additional refractive power between +2.0 D and 10.0 D.

15. The contact lens according to any one of the preceding claims, wherein at a midpoint across the innermost radial width of the treatment zone, the radial sagittal refractive power of the treatment zone matches the nominal distance refractive power of the lens.

16. The contact lens according to claim 15, wherein at the midpoint of the radial width across each treatment zone, the radial sagittal refractive power of the treatment zone matches the nominal distance refractive power of the lens.

17. The contact lens according to any one of claims 1 to 15, wherein at least one treatment zone is a sagittal addition treatment zone having a radial sagittal refractive power greater than the nominal distance refractive power of the lens across the width of the treatment zone.

18. The contact lens according to any one of the preceding claims, wherein the radial sagittal refractive power profile across the central region is approximately flat.

19. The contact lens according to any one of the preceding claims, wherein the radial sagittal refractive power profile across the central region is curved.

20. The contact lens according to claim 19, wherein the radial sagittal refractive power profile across the central region has a quadratic or parabolic shape.

21. The contact lens according to any one of the preceding claims, wherein the radial curvature refractive power of each treatment zone is caused by the curvature of the front surface and / or the back surface of the lens.

22. The contact lens according to any one of the preceding claims, wherein the lens comprises an elastomeric material, a polysiloxane elastomeric material, a hydrogel material, or a polysiloxane hydrogel material or a mixture thereof.

23. The contact lens according to any one of the preceding claims, wherein the lens is formed using a lathe machining process or a casting molding process.

24. A method of manufacturing a contact lens, the method comprising: forming a contact lens according to any one of the preceding claims.

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