Method of manufacturing an ophthalmic lens comprising an asymmetric gradient refractive index optical element

Abstract

A method (100) of manufacturing an ophthalmic lens is described. The method includes providing a lens substrate (103) and providing a photocurable film (105). The method includes using a digital light projection system to photocure at least one region of the film, thereby producing at least one photocured gradient index optical element (107) having an asymmetric refractive index profile. The method includes applying the film to a surface (109) of the lens substrate.

Description

Technical Field

[0001] The present disclosure relates to methods of manufacturing an ophthalmic lens having a film applied to a surface thereof, wherein the film comprises at least one gradient index optical element having an asymmetric refractive index profile that has been photocured using digital light projection (DLP) technology. Background Art

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

[0003] Without 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, then diverges away from that plane and is out of focus when it reaches the retina. Conventional lenses used to correct myopia (e.g., spectacle lenses and contact lenses) reduce the convergence (for contact lenses) of incoming light from distant objects before it reaches the eye, or cause it to diverge (for spectacle lenses), so that the location of the focal point is shifted onto the retina.

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

[0005] It was proposed several decades ago that the progression of myopia in children or young adults could be slowed or prevented by undercorrection (i.e., moving the focus toward the retina but not completely onto the retina). However, such approaches necessarily result in reduced distance vision compared to the vision obtained using lenses that fully correct myopia. Furthermore, it is now considered doubtful that undercorrection is effective in controlling developing myopia. A newer approach is to provide lenses with both fully corrected zones that provide distance vision and zones that are undercorrected or intentionally induce myopic defocus. Lenses that increase the scattering of light in specific zones compared to light that passes through the fully corrected zones of the lens can also be provided. It has been proposed that these approaches can prevent or slow the development or progression of myopia in children or young adults while providing good distance vision.

[0006] In the case of lenses with zones that provide defocus, the zone that provides full correction for distance vision is often referred to as the base power zone, and the zone that provides undercorrection or intentionally induced myopic defocus is often referred to as the add power zone or myopic defocus zone (because the dioptric power is more positive or less negative than the dioptric power of the hyperopic correction base power zone). The surface (usually the front surface) of the add power zone has a smaller radius of curvature than the radius of curvature of the hyperopic power zone, and therefore provides more positive or less negative refractive power to the eye. The add power zone is designed to focus incoming parallel light (i.e., light from a distance) in front of the retina in the eye (i.e., closer to the lens), while the hyperopic 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 viewing a near object and uses accommodation to focus light passing through the hyperopic power zone, the add power zone will focus the light in front of the retina.

[0007] In the case of lenses that increase light scattering in specific areas, features that increase scattering can be introduced into the lens surface or can be introduced into the material used to form the lens. For example, scattering elements can be produced into the lens surface by thermal or mechanical or light induced methods, or embedded in the lens. The scattering elements can be, for example, laser induced material changes to form optical elements embedded in the lens material.

[0008] A known type of contact lens that reduces myopia progression is a bifocal contact lens available under the name MISIGHT (CooperVision). This bifocal lens differs from bifocal or multifocal contact lenses configured to improve vision for presbyopes in that the bifocal lens is configured with specific optical dimensions to enable an adaptable person to view both distant and near objects using the hyperopic correction (i.e., base power). The treatment area of ​​the bifocal lens with added power also provides a myopic defocused image at both distant and near viewing distances.

[0009] While these lenses have been found to be beneficial in preventing or slowing the development or progression of myopia, the annular add power zone may produce unwanted visual side effects. Light focused in front of the retina by the annular add power zone diverges from the focal point to form a defocused ring at the retina. As a result, wearers of these lenses may see a ring or "halo" surrounding the image formed on the retina, especially for small, bright objects such as street lamps and car headlights. Furthermore, in theory, the wearer could utilize the additional annular add power zone to focus on near objects, rather than using the eye's natural accommodation (i.e., the eye's instinct to change focus) to bring near objects into focus; in other words, the wearer may inadvertently use the lens in the same manner as a presbyopia correction lens, which is undesirable for young subjects.

[0010] Further 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. Instead, a far point source of light is imaged by the annular zone to an annular focal line at the near add power focal plane, resulting in a small spot size of light on the retina at the distance focal plane, without a surrounding "halo" effect.

[0011] For treating myopia, it may be beneficial to provide a lens that introduces additional myopic defocus. For treating presbyopia, it may be beneficial to provide a lens that produces an extended depth of focus.

[0012] It is recognized that known lenses that include a therapeutic portion for introducing defocus are generally designed to provide a specific treatment to the lens wearer. The lenses can be expensive and complex in design, and over time, if the needs of the lens wearer change, they may need to purchase different lenses that provide different levels of correction.

[0013] The present invention seeks to provide a simple and cost-effective alternative to known lenses for preventing or slowing the progression of myopia.Such lenses may also be beneficial in correcting or improving vision associated with presbyopia, hyperopia, astigmatism, keratoconus or other refractive abnormalities. Summary of the invention

[0014] According to a first aspect, the present disclosure provides a method according to technical solution 1. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Example embodiments will now be described, by way of example only, with reference to the accompanying schematic drawings.

[0016] Figure 1 is a flow chart illustrating a method of manufacturing an ophthalmic lens according to an embodiment of the present disclosure;

[0017] Figure 2Ais a top view of a film including a plurality of photocured GRIN optical elements according to an embodiment of the present disclosure;

[0018] Figure 2B yes Figure 2A A top view of one of the GRIN optical elements of the lens;

[0019] Figure 2C yes Figure 2A A perspective view of the GRIN optical element shown in FIG.

[0020] Figure 2D It is a display Figure 2B and 2C A diagram of the refractive index distribution of the GRIN optical element shown in FIG.

[0021] Figure 2E Applied to ophthalmic lenses Figure 2A A cross-sectional view of a membrane;

[0022] Figure 3 is a flow chart showing a method for manufacturing an ophthalmic lens using a grayscale image according to an embodiment of the present disclosure;

[0023] Figure 4 is a grayscale image for controlling light from a DLP to produce a single photocured GRIN optical element with an asymmetric refractive index profile;

[0024] Figure 5A is a schematic diagram of a grid for defining desired locations of photocured GRIN optical elements according to an embodiment of the present disclosure;

[0025] Figure 5B is a grayscale image of a triangular lattice arrangement used to control light from a DLP to produce a photocured GRIN optical element with an asymmetric refractive index profile;

[0026] Figure 6 is a 2D plot showing a modeled refractive index profile of a GRIN optical element having an asymmetric refractive index profile;

[0027] Figure 7 is a flow chart showing the conversion of a modeled desired refractive index profile into a light intensity map for use in a method according to an embodiment of the present disclosure;

[0028] Fig. 8A is a top view of a lens having a film including a plurality of photocured GRIN optical elements produced using a method according to an embodiment of the present disclosure;

[0029] Figure 8B yes Fig. 8A a cross-sectional side view of a lens; and

[0030] Fig. 9 is a front view of a pair of eyeglasses incorporating lenses made according to the methods of the present disclosure. DETAILED DESCRIPTION

[0031] According to a first aspect, the present disclosure provides a method of manufacturing an ophthalmic lens. The method includes providing a lens substrate, and providing a photocurable film. The method includes using a digital light projection system to photocuring at least one region of the film, thereby producing at least one gradient index optical element having an asymmetric refractive index profile. The method includes applying the film to a surface of the lens substrate.

[0032] The membrane may be a cross-linked polymer membrane. The membrane may be a thin film. The membrane may have been formed from a matrix of uncross-linked polymer. The membrane may be HX membrane. The membrane can have a uniform thickness.

[0033] An ophthalmic lens (which may be referred to hereinafter as a lens) may be a lens for preventing or slowing the development or progression of myopia. A lens may be a lens for correcting or improving vision associated with presbyopia, hyperopia, astigmatism, keratoconus, or another refractive abnormality.

[0034] The lens substrate may be applied to the ophthalmic lens during manufacture of the lens.Alternatively, the lens substrate may be an ophthalmic lens.

[0035] The film may cover the entire surface of the lens, or substantially all of the surface of the lens. Alternatively, the film may cover a portion of the surface of the lens. The film may cover a central portion of the surface of the lens, for example, the portion configured to be located in front of the eye of the lens wearer when the ophthalmic lens is in use. The film may cover an annular area of ​​the surface surrounding the center of the lens. There may be a peripheral area of ​​the lens that is not covered by the film.

[0036] The base refractive index of the film may be uniform. The base refractive index of the film may be between 1.3 and 1.8, preferably about 1.5. Each of the at least one GRIN optical element may have an average refractive index greater than the base refractive index. Alternatively, each of the at least one GRIN optical element may have an average refractive index less than the base refractive index.

[0037] The lens will have an optical axis. The optical axis of the lens is defined with reference to a distant point source of light. 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 along the centerline of the lens. For example, where the lens is a contact lens, the optical axis is typically 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, where the position of the optical axis of the lens will be determined by the wearer's pupil distance, which, depending on the lens geometry, may not coincide with the centerline of the lens. When the film is applied to the lens, at least one gradient refractive index (GRIN) optical element will focus light from a distant point source on the optical axis to a point at a first distance from the optical axis of the lens.

[0038] When the film is applied to the lens, light passing through the film from a distant on-axis point source will be focused to a focal point on the optical axis of the lens. The base power focal plane can be defined as a surface that is perpendicular to the optical axis of the lens and passes through the focal point of the lens. The term surface as used herein does not refer to a physical surface, but rather to a surface that can be drawn through a point that will focus light from a distant object. This surface is also called an image plane (even though it may be a curved surface) or an image shell. The eye focuses light onto the curved retina, and in a perfectly focusing eye, the curvature of the image shell will match the curvature of the retina. Therefore, the eye does not focus light onto a flat mathematical plane. However, in the art, the curved surface of the retina is typically referred to as a plane. When the film is applied to the lens, light passing through the film from an on-axis point source is focused to a focal point on the optical axis of the lens at the base power focal plane.

[0039] In the context of the present disclosure, each of the at least one GRIN optical element is an element having a varying and asymmetric refractive index distribution in a plane parallel to the surface of the film. Each element may be substantially cylindrical, or cylindrical with an elliptical or oval cross section, and may have its cylindrical axis perpendicular to the plane of the layer. Each element may be substantially spherical or cubic. Each element may have a circular, elliptical, oval or square cross section in a plane parallel to the surface of the film. Each element may have a circular, elliptical, oval or square cross section and a flat plane flush with the surface of the film. In embodiments of the present disclosure, the refractive index variation across at least one GRIN optical element will be asymmetric in at least one lateral direction (i.e., the direction parallel to the surface of the layer). Due to the asymmetric refractive index distribution, when the film is applied to the lens, light passing through at least one GRIN optical element from a far point source on the axis will be directed toward a point that is not on the optical axis of the lens (i.e., off-axis focus).

[0040] Each of the at least one GRIN optical element is a lens having its own local optical axis. When the film is applied to the lens, the local optical axis of each of the at least one GRIN optical element is tilted relative to the optical axis of the lens due to the asymmetric refractive index distribution. The local optical axis of each of the at least one GRIN optical element is defined with reference to a distant point source. Light from a distant point source on the local optical axis of the GRIN optical element (which may be referred to as an on-axis distant point source hereinafter) will be focused onto the local optical axis of the GRIN optical element. A GRIN optical element having an asymmetric refractive index variation in a direction parallel to the surface of the film (i.e., a transverse direction) will have a local optical axis tilted relative to the optical axis of the lens, and therefore, light from an on-axis distant point source passing through each of the GRIN optical elements will be focused to a point at a first distance from the optical axis of the lens. The focal power of each of the GRIN optical elements will depend on the refractive index distribution of the GRIN optical element.

[0041] Any or all of the at least one GRIN optical element may be configured such that when the film is applied to the lens, light from an on-axis distant point source passing through the GRIN optical element forms a small spot of light centered on the optical axis of the lens at the base power focal plane. Thus, although each of the GRIN optical elements may focus light toward an off-axis focus, the approximate superposition of the image formed by light passing through the region of the lens having the base refractive index and the defocused image formed by light passing through the GRIN optical element may improve the quality or contrast of the image formed at the retina, and may improve the vision of the lens wearer. Alternatively, any or all of the at least one GRIN optical element may be configured such that when the film is applied to the lens, light from an on-axis distant point source passing through the GRIN optical element does not intersect the optical axis of the lens at the base power focal plane. This may result in reduced contrast or reduced image quality of the image formed at the retina, which may be advantageous in reducing myopia progression.

[0042] The asymmetric refractive index variation may be a radial refractive index variation, i.e., the refractive index may vary extending radially outward from a point at the center of the GRIN optical element and in a plane parallel to the surface of the film (i.e., a transverse plane). The asymmetric refractive index variation may be in a circumferential direction, i.e., the refractive index may vary around the circumference of the GRIN element in a plane parallel to the surface of the film, and the refractive index variation may be different along different meridians of the GRIN optical element.

[0043] An asymmetric refractive index variation may be a variation in a linear direction parallel to the surface of the film.

[0044] The asymmetric refractive index variation may be a combination of variation in a linear direction in the transverse plane and variation in the radial and / or circumferential directions.

[0045] Advantageously, GRIN optical elements can provide defocus. It is believed that defocus can help prevent or slow the progression of myopia. It is believed that defocus can help correct or improve vision associated with presbyopia, hyperopia, astigmatism, keratoconus or other refractive abnormalities. GRIN optical elements can be arranged so that they provide random refractive index modulation across the membrane, thereby increasing the spread of light across the retina and reducing image contrast.

[0046] The refractive index variation of any of the at least one GRIN optical element may be defined by an asymmetric polynomial function.

[0047] The film may include a plurality of GRIN optical elements. The film may include a plurality of GRIN elements randomly distributed across the layers. A plurality of GRIN elements may be randomly distributed across portions of the film. The film may include a plurality of GRIN optical elements arranged to form at least one annular ring. At least one annular ring may be circular, oval or elliptical in shape. The film may have a film axis extending in a direction substantially perpendicular to the plane of the film. If the film has a substantially circular cross-section, the film axis may be positioned at the radial midpoint of the film, or the film axis may be oriented toward the radial midpoint of the film. At least one annular ring may be centered on the film axis. When the film is applied to the lens, the film axis may coincide with the optical axis of the lens. When the film is applied to the lens, the film may be configured so that at least one annular ring is centered on the optical axis of the lens. The film may be configured so that a plurality of GRIN optical elements may be arranged to form at least two concentric annular rings positioned at different radial distances from the optical axis of the lens.

[0048] If the lens is a spectacle lens, it may be advantageous to distribute the GRIN optical elements across a relatively large area of ​​the lens substrate, as this may enable the defocus caused by the GRIN optical elements to be maintained as the lens wearer's eye moves relative to the lens. Multiple GRIN optical elements distributed across a spectacle lens may enable consistent myopic defocus to be maintained.

[0049] GRIN optical elements can be positioned at regular intervals across the entire film or portions of the film. GRIN optical elements can be arranged at the grid points of a triangular lattice. GRIN optical elements can be arranged at the grid points of a square or rectangular lattice.

[0050] The GRIN optical elements can be arranged to form an annular pattern on the film. When the film is applied to a lens, the film can be configured so that the annular pattern leaves a central region of the lens without GRIN optical elements. The lens can have a central region with a diameter of up to 8 mm that does not have GRIN optical elements. The annular pattern can include a single ring or multiple concentric rings.

[0051] The film may include at least one second annular ring of GRIN optical elements. When the film is applied to a lens, the second annular rings of optical elements may be positioned at different radial distances from the optical axis of the lens.

[0052] At least two of the GRIN optical elements may be substantially identical, i.e., they may have the same size and shape, and they may have the same asymmetric refractive index profile. In this case, when the film is applied to the lens, the at least two GRIN optical elements may focus light from an on-axis distant point source toward a point that is not on the optical axis of the lens and is located on the same focal plane. The refractive index profiles of the at least two GRIN elements may vary so that when the lens is positioned on the eye, light from an on-axis distant point source that passes through the GRIN optical elements will be located at a surface that is closer to the back surface of the lens than the base refractive power focal plane. The refractive index profiles of the at least two GRIN elements may vary so that when the lens is positioned on the eye, light from an on-axis distant point source that passes through the GRIN optical elements will be focused at a surface that is farther from the back surface of the lens than the base refractive power focal plane.

[0053] When the film is applied to a lens, substantially identical GRIN optical elements positioned at the same radial distance from the optical axis of the lens (e.g., GRIN optical elements arranged in circular concentric rings centered on the optical axis) can focus light toward off-axis points equidistant from the optical axis from the lens and located on the same focal plane. Thus, the focal points formed by light passing through these GRIN optical elements can form a circular ring at the focal plane. Similarly, substantially identical GRIN optical elements can be arranged to form an elliptical or oval ring centered on the optical axis, and the focal points formed by light passing through these GRIN optical elements from a distant point source on the axis can form an elliptical or oval ring at the focal plane.

[0054] At least two of the GRIN optical elements may have different asymmetric refractive index profiles. In this case, at least two GRIN optical elements will have different local optical axes. When the film is applied to the lens, for the first and second GRIN elements having different refractive index profiles and positioned at the same radial distance from the optical axis of the lens, light from an on-axis distant point source passing through the first GRIN optical element may be focused to a point a first distance away from the optical axis of the lens, and light from an on-axis distant point source passing through the second GRIN optical element may be focused to a point a second, different distance away from the optical axis of the lens. The focal point of each of the GRIN optical elements will depend on the asymmetric refractive index profiles of the GRIN elements, and the positions of the GRIN optical elements.

[0055] When the film is applied to a lens, at least two of the GRIN optical elements having different refractive index profiles can focus light toward different focal planes.

[0056] Each of the plurality of GRIN optical elements may have a different refractive index variation. Alternatively, some GRIN optical elements may have the same refractive index variation and other elements may have different refractive index variations. The plurality of GRIN optical elements may be distributed such that GRIN optical elements with the same or similar refractive index variation may be clustered or grouped in an ordered arrangement. The film may be divided into a plurality of distinct portions, wherein each portion includes a GRIN optical element with the same or similar refractive index variation.

[0057] When the film is applied to a lens, there may be a correlation between the refractive index profile of each of the at least one GRIN optical element and the radial position of the element from the film axis and / or the optical axis of the lens. GRIN optical elements positioned at the same radial distance from the film axis and / or the optical axis of the lens (e.g., positioned around a ring centered around the film axis and / or the optical axis of the lens) may have the same refractive index profile. GRIN elements positioned at different radial distances from the film axis and / or the optical axis of the lens may have different refractive index profiles.

[0058] GRIN optical elements positioned at a greater radial distance from the film axis and / or the optical axis of the lens may have a refractive index profile that results in greater power than GRIN optical elements positioned at a smaller radial distance from the film axis and / or the optical axis of the lens. When the ophthalmic lens is in use, the GRIN optical elements positioned at a greater radial distance from the optical axis of the lens may focus light from an on-axis distant point source toward a surface closer to the posterior surface of the lens substrate than the GRIN optical elements positioned at a smaller radial distance from the optical axis of the lens.

[0059] The film may include GRIN optical elements forming a first annulus and these GRIN elements may have a first refractive index distribution. The film may include GRIN elements forming a second annulus and these GRIN elements may have a second different refractive index distribution. The first annulus may be at a smaller radial distance from the optical axis of the lens and / or the axis of the film than the second annulus. When the film is applied to the lens, the first refractive index distribution may cause the GRIN optical elements forming part of the first annulus to focus light toward the first focal plane, and the second refractive index distribution may cause the GRIN elements forming the second annulus to focus light toward the second focal plane. When the lens is worn by a user, the first focal plane and / or the second focal plane may be closer to the back surface of the lens than the base focal plane. The first focal plane may be closer to the back surface of the lens than the second focal plane. The first focal plane may be farther away from the back surface of the lens than the second focal plane.

[0060] The film may include GRIN optical elements forming a plurality of concentric annular rings. The GRIN optical elements within the same annular ring may have the same refractive index profile. The GRIN optical elements forming different annular rings may have different refractive index profiles. An annular ring positioned at a greater radial distance from the optical axis of the lens and / or the axis of the film may include a GRIN element having a refractive index variation that results in a greater focal power of the element. When the lens is in use, an annular ring positioned at a greater radial distance from the optical axis of the lens substrate may include a GRIN element that focuses light toward a surface closer to the rear surface of the lens than an annular ring positioned at a smaller radial distance from the optical axis of the lens. Alternatively, an annular ring positioned at a greater radial distance from the optical axis of the lens and / or the axis of the film may include a GRIN element with a smaller focal power. When an ophthalmic lens including the lens is in use, an annular ring positioned at a greater radial distance from the optical axis of the lens may include a GRIN element that focuses light toward a surface farther from the rear surface of the lens than an annular ring positioned at a smaller radial distance from the optical axis of the lens.

[0061] Each of the at least one GRIN optical element can produce additional scattering of light incident on the GRIN optical element compared to light incident on the remainder of the film.

[0062] Each of the at least one GRIN optical element may have a minimum refractive index difference of at least 0.001, preferably at least 0.005, compared to the base refractive index. Each of the at least one GRIN optical element may have a minimum refractive index of 0.001 greater than the base refractive index. Each of the at least one GRIN optical element may have a minimum refractive index of 0.005 greater than the base refractive index. Each of the at least one GRIN optical element may have a maximum refractive index of 0.005 less than the base refractive index. Each of the at least one GRIN optical element may have a maximum refractive index of 0.001 less than the base refractive index. Each of the at least one GRIN optical element may have a maximum refractive index difference of less than 0.1, preferably less than 0.025, compared to the base refractive index. Each of the at least one GRIN optical element may have a maximum refractive index of 0.1 greater than the base refractive index. Each of the at least one GRIN optical element may have a maximum refractive index of 0.025 greater than the base refractive index. Each of the at least one GRIN optical element may have a minimum refractive index of 0.1 less than the base refractive index. Each of the at least one GRIN optical element may have a minimum refractive index that is 0.025 less than the base refractive index. Each of the at least one GRIN optical element may have a minimum refractive index that is equal to the base refractive index. Each of the at least one GRIN optical element may have a minimum refractive power between -25D and +25D, preferably between -0.25D and +25.0D. For lenses used to prevent or slow the development or progression of myopia, each GRIN optical element may have a minimum refractive power between -0.25D and +25.0D. For lenses used to prevent or slow the development or progression of hyperopia, each GRIN optical element may have a minimum refractive power between 0.0 and -25.0D.

[0063] The film has a finite thickness, and each of the at least one GRIN optical element may extend through the thickness of the film. Each of the at least one GRIN optical element may extend only partway through the thickness of the film. Each of the at least one GRIN optical element may be embedded within the film. The thickness of the film may be uniform. Each of the at least one GRIN optical element may be embedded within the film without changing the thickness of the film. Each of the at least one GRIN optical element may have a uniform thickness. Each of the at least one GRIN element may have a flat surface flush with the surface of the film.

[0064] The film may be a cross-linked polymer film comprising at least one GRIN optical element. The film may have been formed from a matrix of uncross-linked polymer. The film may be bonded to a lens substrate. Plasma may be used to bond the film to the lens substrate. The film may be adhered to the lens substrate. A curable adhesive may be used to adhere the film to the lens substrate.

[0065] The film may be disposed on the lens substrate and / or the front surface of the lens. The film may be disposed on the lens substrate and / or the back surface of the lens. The film may be disposed on the lens substrate and / or both the front and back surfaces of the lens. The film may include HX Film. The film may be releasably adhered or otherwise applied to a lens substrate, i.e., it may be easily removed from the lens substrate. The film may be reusable, such that the film may be easily removed and reapplied to the same substrate or a different lens substrate.

[0066] The film may have a uniform thickness.

[0067] The film may be a flexible transparent film. For contact lenses, the film may have a thickness between 1 μm and 100 μm, preferably between 10 μm and 20 μm, and more preferably between 14 μm and 18 μm. For eyeglass lenses, the film may have a thickness between 1 μm and 1000 μm, preferably between 10 μm and 20 μm, and more preferably between 14 μm and 18 μm.

[0068] The lens substrate may be applied to an ophthalmic lens during manufacture of the lens. The lens substrate may be releasably adhered or otherwise applied to the ophthalmic lens, i.e., it may be easily removed from the ophthalmic lens. The lens substrate may be reusable, such that the lens substrate may be easily removed and reapplied to the same lens substrate or a different lens substrate. Alternatively, the lens substrate may be an ophthalmic lens.

[0069] The ophthalmic lens may be a spectacle lens. The spectacle lens may include PMMA, CR-39, polycarbonate, Trivex, or crown glass. The ophthalmic lens may be a contact lens. The film may be disposed on the front surface of the ophthalmic lens. In the context of the present disclosure, the front surface of the ophthalmic lens is the front-facing or outer surface of the lens when the ophthalmic lens is worn by a lens wearer.

[0070] The ophthalmic lens may be circular in shape. The ophthalmic lens may be elliptical in shape. The ophthalmic lens may be oval in shape. The ophthalmic lens may be rectangular in shape. The ophthalmic lens may be square in shape. The front surface of the ophthalmic lens may have a diameter between 1200 mm and 1200 mm. 2 Up to 3000mm 2 The area between. The ophthalmic lens may be formed from clear glass or a rigid plastic such as polycarbonate. The ophthalmic lens may be substantially planar and may have at least one curved surface that provides the refractive power of the lens.

[0071] The ophthalmic lens may be a contact lens. 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 such a contact lens will provide clinically acceptable supraorbital movement and will not be combined with one or both eyes of a person. The contact lens may be in the form of a corneal lens (e.g., a lens that rests on the cornea of ​​the eye). In embodiments where the lens is a contact lens, the lens may have a diameter between 60 mm and 100 mm. 2 Up to 750mm 2 The lens may have a surface area between 10 mm and 15 mm. The lens may have a circular shape. The lens may have an oval shape. The lens may have an elliptical shape. The lens may have a diameter between 10 mm and 15 mm.

[0072] The lens may be a rigid contact lens. The lens may be a rigid gas permeable contact lens.

[0073] The contact lens may be a toric contact lens. For example, a toric contact lens may include an optical zone that is shaped to correct a person's astigmatism. The lens may be a scleral contact lens.

[0074] The ophthalmic lens may be a soft contact lens, such as a hydrogel contact lens or a silicone hydrogel contact lens.

[0075] The ophthalmic 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 equilibrium and is free of silicone-containing chemicals. A silicone hydrogel is a hydrogel containing silicone-containing chemicals. The hydrogel material and silicone hydrogel material as described in the context of the present disclosure have an equilibrium water content (EWC) of at least 10% to about 90% (wt / wt). In some embodiments, the hydrogel material or silicone hydrogel material has an EWC of from about 30% to about 70% (wt / wt). In contrast, the silicone elastomeric material as described in the context of the present disclosure has a water content of from about 0% to less than 10% (wt / wt). Typically, the silicone elastomeric material used with the present method or apparatus has a water content of from 0.1% to 3% (wt / wt). Examples of suitable lens formulations include those 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, 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, lehfilcon A, and the like.

[0076] Alternatively, the ophthalmic lens may comprise, consist essentially of, or consist of a silicone elastomer material. For example, the lens may comprise, consist essentially of, or consist of a silicone elastomer material having a Shore A hardness 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). Other silicone elastomer materials may be obtained, for example, from NuSil Technology or Dow Chemical.

[0077] An ophthalmic lens may have 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 or in front of the pupil of the eye when in use. The optical zone may be surrounded by a peripheral zone. The peripheral zone is not part of the optical zone, but is located outside the optical zone. For contact lenses, the peripheral zone may be located above the iris when the lens is worn. The peripheral zone may provide mechanical functions, such as increasing the size of the lens, thereby making the lens easier to handle. For contact lenses, the peripheral zone may provide ballasting to prevent rotation of the lens, and / or provide a shaped zone that improves the comfort of the lens wearer. The peripheral zone may extend to the edge of the lens. In embodiments of the present disclosure, when the film is applied to the lens substrate, the film may cover the optical zone, but it may be the case that it does not cover the peripheral zone.

[0078] Each of the at least one GRIN optical element may have a width between 1 μm and 5 mm, preferably between 10 μm and 2 mm. Each of the at least one GRIN optical element may have a width between 1 μm and 5 mm, preferably between 10 μm and 2 mm. 3 Up to 5mm 3 between, preferably between 10 μm 3 Up to 2mm 3 The plurality of GRIN optical elements may occupy between 5% and 80% of the volume of the film. The plurality of GRIN optical elements may cover between 20% and 80% of the surface area of ​​the film. The film may contain between 2 and 5000 GRIN optical elements.

[0079] The lens may have a central area and an annular area surrounding the central area. When the film is applied to the lens, the film may cover part of the annular area. It may be the case that the film does not cover the central area, and therefore the central area may not have GRIN optical elements. The film may cover the entire annular area, or part of the annular area. As used herein, the term annular area refers to a zone that may extend around the entire outer edge of the central area or may extend partially around the outer edge of the central area. The annular area may be circular, oval or elliptical in shape. The annular area may include multiple GRIN optical elements. Multiple GRIN optical elements may be distributed around the entire annular area, or may be distributed across parts of the annular area.

[0080] The film may comprise a plurality of concentric annular zones radially separated by zones of the film having a base refractive index.

[0081] The lens may further include an adhesive disposed between the film and the surface of the lens substrate. The adhesive may include a transparent adhesive, such as an epoxy-based adhesive. The adhesive may be an adhesive layer. The adhesive layer may be applied to the front surface of the lens substrate during manufacture of the lens. The adhesive may permanently adhere the layer to the surface of the lens substrate. Alternatively, the film may be bonded to the surface of the substrate. The film may be permanently or irreversibly bonded to the surface of the substrate.

[0082] The lens may further include a protective layer disposed on the front surface of the film. When the lens is in normal use and worn by the lens wearer, the front surface of the film comprising at least one GRIN optical element is the front-facing surface or outer surface of the film. The protective layer may cover all or part of the front surface of the film. The protective layer may be a transparent layer. The protective layer may include polycarbonate (PC). The protective layer may include polyethylene terephthalate (PET) or triacetyl cellulose (TAC). The protective layer may include a substance with negligible birefringence. The protective layer may be impermeable. The protective layer may be scratch-resistant. The protective layer may have a basic refractive index. The protective layer may provide a certain degree of UV protection. The protective layer may be adhered to the film using an adhesive.

[0083] In the context of the present disclosure, a photocured GRIN optical element is a GRIN optical element that has been formed by photocuring or photopolymerization. A photocured GRIN optical element may be produced from photopolymerizable or photocurable molecules or other photocurable elements. Photocuring results in an asymmetrically varying refractive index across the photocured area. The photocurable molecules may be dispersed within the film. The photocurable molecules may be dispersed within a cross-linked polymer matrix, or within a resin.

[0084] Each of the at least one GRIN optical element may have an asymmetric refractive index profile in a plane or direction parallel to the surface of the film. The asymmetric refractive index profile may be defined by an asymmetric polynomial function. Each of the at least one GRIN optical element may have an asymmetric refractive index profile that varies along a radial direction in a plane parallel to the surface of the film. Each of the at least one GRIN optical element may have an asymmetric refractive index profile that varies in at least one linear direction parallel to the surface of the film. Each of the at least one GRIN optical element may have an asymmetric refractive index profile that varies along a circumferential direction in a plane parallel to the surface of the film.

[0085] In the context of the present disclosure, a digital light projection (DLP) system is a light illumination system that is used to direct light toward a photocurable film, thereby enabling regions of the film to be photocured. The DLP system used has a wavelength that is suitable for photopolymerization or photocuring of the target film material. For example, for HX film, the DLP system may have a wavelength in the range between 440nm to 660nm. The pixel resolution of the DLP system may be less than 100μm, preferably less than 30μm, and more preferably less than 10μm. The DLP system may be a commercial DLP system, for example, a 3DLP9000-LED.9" WQXGA light engine with a 460nm wavelength and a 30nm pixel resolution. The DLP system may include a microelectromechanical system (MEMS). The DLP system may include a digital mirror device. The digital mirror device may guide light and / or control light transmission toward the film.

[0086] The DLP system can be used to illuminate the entire film, or a region of the film. The DLP system can be used to photocuring individual photocurable elements or molecules, or multiple individual photocurable molecules. Multiple individual photocurable molecules can be photocured sequentially or simultaneously. The DLP system can be used to illuminate an annular region of the film, or multiple concentric annular regions of the film.

[0087] Using a digital light projection system may include using a grayscale image to control the projection of light onto the film. The grayscale image may provide a template for projecting light from the DLP system onto the film. The grayscale image may be a .bmp image. The grayscale image may mask some areas of the film so that these areas are not exposed to the light from the DLP system while exposing at least one area of ​​the film to the light from the DLP system. The grayscale image may expose multiple areas to the light from the DLP system. The areas of the film exposed to the light from the DLP system may be photocured to produce a photocured GRIN optical element.

[0088] A method of making a lens may include creating a design for a film, wherein the design has a desired pattern of photocured GRIN optical elements with an asymmetric refractive index profile. The method may include using the design to generate a grayscale image.

[0089] The grayscale image may be designed to produce any arrangement of the photocured GRIN elements described above, wherein the GRIN optical elements have an asymmetric refractive index distribution. The grayscale image may include multiple pores that enable light from the DLP system to reach the film. The area of ​​the film illuminated by the light from the DLP system may be photocured. The image may include blocking or shielding multiple portions of the film from light. The area of ​​the film not illuminated by the light from the DLP system will not be photocured. The image may include multiple pores arranged in a pattern. The desired pattern of the photocured GRIN optical element may be an array of GRIN optical elements arranged on the lattice points of the film, and in this case, the image may include multiple pores arranged on the lattice points. The lattice may be a triangular lattice, a square lattice, or a cubic lattice. Alternatively, the desired pattern of the photocured gradient refractive index optical element may include at least one annular ring of the photocured gradient refractive index optical element. The desired pattern of the photocured gradient refractive index optical element may include multiple concentric annular rings of the photocured gradient refractive index optical element.

[0090] The method may include modeling a desired asymmetric refractive index profile for each of at least one photocured GRIN element and determining at least one exposure condition required to produce the desired asymmetric refractive index profile.

[0091] Modeling can be used to determine the intensity of exposure and / or the duration of exposure and / or the wavelength of exposure required to photocure a GRIN element having a desired asymmetric refractive index profile. The conditions may depend on the characteristics of the DLP system, such as the wavelength, intensity, and type of light source. The conditions may depend on the film properties, such as the film material and film thickness. Any suitable modeling software (e.g., MATLAB®) may be used to determine the intensity of exposure and / or the duration of exposure and / or the wavelength of exposure required to photocure a GRIN element having a desired asymmetric refractive index profile. The conditions may depend on the characteristics of the DLP system, such as the wavelength, intensity, and type of light source. The conditions may depend on the film properties, such as the film material and film thickness. TM ) to perform modeling. Modeling may be performed using experimental (measured) data or theoretical (predicted) data. The predicted data may be based on known properties of the film material and / or the DLP system. The desired refractive index profile for each of the photocured GRIN elements may be defined by an asymmetric polynomial function, or may be approximated by an asymmetric polynomial function. The desired asymmetric refractive index profile may be modeled for a single photocured GRIN element, or for multiple photocured GRIN elements. For a film comprising multiple GRIN optical elements, the desired asymmetric refractive index profile for each of at least one photocured GRIN element may be the same, or each of the photocured GRIN elements may have a different desired asymmetric refractive index profile.

[0092] The modeling step may include measuring or plotting a desired refractive index change map that varies depending on exposure conditions. The exposure conditions may be light intensity, duration of exposure, or wavelength of light. The map may be generated as a map with a non-planar surface. The map may be generated as a 3D map. The map may be iteratively updated and / or optimized to produce the desired refractive index distribution of the photocured GRIN optical element. The map may be a refractive index change map of a single photocured GRIN optical element or a plurality of photocured GRIN optical elements. The map may be used to generate a refractive index gradient pixel matrix for use in a DLP imaging system. The pixel matrix may identify the required exposure conditions for each pixel of the DLP imaging system to produce the desired refractive index change across the membrane. The refractive index gradient pixel matrix may be configured to produce a single photocured GRIN optical element, or between 2 and 5000 photocured GRIN elements distributed across the membrane. The refractive index gradient pixel matrix may be configured to produce photocured GRIN elements across an area between 20% and 80% of the membrane.

[0093] The modeling step may include converting the refractive index variation map into a digital light projection intensity map. The digital light projection intensity map may be a pixel matrix for a DLP system. The digital light projection intensity map may be generated from a refractive index gradient pixel matrix. The digital light projection intensity map may be used when generating a grayscale image for use in a DLP system. The digital light projection intensity map may be used to determine the required exposure conditions for use in a DLP system. A DLP intensity map may be used to generate a .bmp image. The image may be an 8-bit map. The exposure conditions may depend on the film type, the desired pattern or arrangement of the photocured GRIN optical elements, the film properties, and the properties of the DLP imaging system. Therefore, the digital light projection intensity map may be used to control the light projection onto the film by determining the required exposure conditions.

[0094] The modeled desired refractive index distribution may result in an asymmetric refractive index distribution when the refractive index variation map is converted into a digital light projection intensity map.

[0095] The desired refractive index profile may result in an asymmetric refractive index profile that varies along a radial direction in a plane parallel to the surface of the film. The desired refractive index profile may result in an asymmetric refractive index profile that varies along at least one linear direction parallel to the surface of the film. The desired refractive index profile may result in an asymmetric refractive index profile that varies along a circumferential direction in a plane parallel to the surface of the film.

[0096] The modeling step may include modeling at least two different desired refractive index profiles of at least two different photocured GRIN optical elements. The modeling step may include selecting a desired refractive index profile of at least one GRIN optical element depending on the position of each of the elements within the desired pattern. If the desired pattern of GRIN optical elements includes a plurality of concentric annular rings of photocured gradient refractive index optical elements, the modeling step may include selecting the same desired refractive index profile of GRIN optical elements forming the same annular ring. The modeling step may include selecting different desired refractive index profiles of GRIN optical elements forming portions of different annular rings. The modeling step may include selecting a desired refractive index for each of at least one GRIN optical element such that GRIN optical elements positioned at the same radial distance from the film axis have the same desired refractive index profile. The modeling step may include selecting a desired refractive index profile for each of at least one GRIN optical element such that GRIN optical elements positioned at a greater distance from the film axis have a more asymmetric desired refractive index profile. Alternatively, the modeling step may include selecting a desired refractive index profile for each of the at least one GRIN optical element such that GRIN optical elements positioned at greater distances from the film axis have a more symmetric desired refractive index profile.

[0097] The method may include exposing the film to light from the DLP using a grayscale image and / or a digital light projection intensity map to control the exposure of light projected across the film. The method may include waiting a minimum amount of time for the film to develop. The method may include flood curing or flood exposing the film using a DLP system or using a UV oven after waiting the minimum amount of time for the film to develop.

[0098] The DLP system may include optics that cause a nonlinear intensity response. The method may involve determining whether there is a significant nonlinear response at any or all pixels. If there is a significant nonlinear response, the method may include adapting the digital light projection intensity map to account for the nonlinear response.

[0099] The desired refractive index profile for each of the at least one GRIN optical element can produce a photocured GRIN optical element having a diameter between about 1 μm and 5.0 mm. The modeled refractive index profile can be configured to produce at least one photocured GRIN optical element having a diameter between about 1 μm and 5.0 mm. The modeled refractive index profile can be optimized or iteratively optimized to produce at least one photocured GRIN optical element having a diameter between about 1 μm and 5.0 mm. The desired refractive index profile for each of the at least one photocured GRIN optical element can produce a photocured GRIN optical element having a diameter between about 1 μm and 5.0 mm. 3 Up to 5mm 3 The desired refractive index profile of each of the at least one photocured GRIN optical element can produce a disk-shaped photocured GRIN element or a spherical photocured GRIN element having an asymmetric distribution in a direction parallel to the surface of the film. The modeled refractive index profile can be optimized or iteratively optimized to produce at least one photocured GRIN optical element having any of the properties described above.

[0100] The method may include applying the film to the surface of the lens or lens substrate after photocuring. The film may be placed on the second substrate for photocuring before being removed from the second substrate and applied to the lens or lens substrate. The second substrate may be a glass slide. The film may be applied to the surface of the lens before photocuring. An adhesive (e.g., an epoxy adhesive) may be used to adhere the film to the surface of the lens. The adhesive may be an adhesive layer. The adhesive layer may be applied to the front surface of the lens during the manufacture of the lens. The adhesive layer may be applied to the back surface of the film before the film is applied to the lens surface. The adhesive may permanently adhere the film to the surface of the lens. The adhesive may releasably adhere the film to the surface of the lens.

[0101] Before applying the film to the lens or lens substrate (this can be before or after the area of ​​the film is photocured), the film can be cut or shaped to be suitable for application to an ophthalmic lens. The film can be cut or shaped to cover the entire surface of the lens, or a portion of the surface of the lens. The film can be cut or shaped into a circular, oval or elliptical shape. The film can be cut or shaped to cover the optical zone of the lens, or the area of ​​the lens that will be positioned in front of the retina of the lens wearer when the lens is worn by the lens wearer.

[0102] Prior to photocuring, a protective layer may be applied to the surface of the film. The method may include removing the protective layer prior to photocuring. The protective layer may include polypropylene.

[0103] After applying the photocured film to the lens, the method may include applying a protective layer to the front surface of the lens (i.e., on top of the photocured layer). The protective layer may cover all or part of the front surface of the film containing at least one photocured GRIN optical element. The protective layer may be a transparent layer. The protective layer may include polycarbonate (PC). The protective layer may include polyethylene terephthalate (PET) or triacetate cellulose (TAC). The protective layer may include a substance with negligible birefringence. The protective layer may be impermeable. The protective layer may be scratch-resistant. The protective layer may have a basic refractive index. The protective layer may provide a degree of UV protection. The protective layer may be adhered to the film containing at least one photocured GRIN optical element using an adhesive.

[0104] Figure 1 is a flow chart showing a method 100 of manufacturing an ophthalmic lens according to an embodiment of the present disclosure. In a first step 103, an ophthalmic lens is provided, and in a second step 105, a photocurable film is provided. In a third step 107, at least one photocured GRIN element having an asymmetric refractive index profile is produced inside the photocurable film using digital light projection (DLP). The DLP system will direct light towards the photocurable film and will illuminate an area of ​​the film, and thereby at least one photocured GRIN element having an asymmetric refractive index profile will be produced. In a fourth step 109, the film is applied to the surface of the lens substrate.

[0105] Figure 2A 1 is a schematic top view of a film 1 for application to an ophthalmic lens produced using a method according to an embodiment of the present disclosure, the film 1 comprising a plurality of light-cured GRIN optical elements 7a, 7b. The GRIN optical elements 7a, 7b are arranged in concentric circles 9a, 9b (dashed lines 9a, 9b are provided as a guide to the eye and do not represent structural features of the film 1). The concentric circles are centered on the film axis 3, which extends in a direction substantially perpendicular to the plane of the film 1. Figure 2B yes Figure 2A A top view of one of the GRIN optical elements 7a of the film 1 shown in FIG. 1 , and Figure 2CThe same element 7a is shown in perspective. Each of the GRIN optical elements 7a, 7b is substantially cylindrical in shape having an elliptical cross-section in a plane parallel to the surface of the film 1. Each of the GRIN optical elements 7a, 7b has a refractive index profile that varies in both the radial direction and the lateral direction in a plane perpendicular to the cylindrical axis of the elements 7a, 7b (i.e., a plane parallel to the surface of the film 1), resulting in an asymmetric refractive index profile across the elements 7a, 7b. The refractive index across the surface of the elements 7a, 7b varies in a plane perpendicular to the cylindrical axis of the element 7a, varies radially outward from point 'X' in a plane parallel to the front surface of the film 1, and varies laterally in a direction parallel to the front surface of the film 1 indicated by arrow 'Y'. The refractive index profile is constant (i.e., does not vary) in the direction 'Z' parallel to the cylindrical axis of the elements 7a, 7b (see FIG. 2 ). Figure 2C ). The refractive index variation has an asymmetric distribution 22 in the direction 'Y', such as Figure 2D As shown in .

[0106] The GRIN optical elements 7a forming the inner circle 9a all have the same refractive index distribution (eg Figures 2B to 2D ) and are all positioned at the same radial distance from the membrane axis 3. Figure 2E The lens substrate 5 (in this case, the lens substrate 5 is an ophthalmic lens 5) is shown applied to the lens substrate 5 Figure 2A 2. A cross-sectional view of the film 1 of FIG. 2. The film axis 3 is aligned with the optical axis 2 of the lens 5. Since the GRIN optical element 7a has an asymmetric refractive index profile, when the film 1 is applied to the lens 5, the local optical axis of the GRIN element 7a will be tilted relative to the optical axis 2 of the lens 5. Light from a distant point source on the optical axis 2 of the lens 5 (hereinafter referred to as an on-axis distant point source) passing through a region of the film 1 having a basic refractive index will be focused to a light spot 11 on the optical axis 2. Light from the on-axis distant point source passing through the GRIN optical element 7a will be focused away from the optical axis 2 of the lens 5. Light from the on-axis distant point source passing through the GRIN optical element 7a forming the inner ring 9a will form a ring of focal points 15a, 15b at the focal plane 17. When the lens 5 is worn by a lens wearer, the GRIN elements 7a forming the inner ring 9a focus light from an on-axis far point source toward an additional power focal plane 17, which is closer to the back surface of the lens 5 (i.e., farther from the retina, or closer to the cornea) than the base power focal plane 13. The local optical axis of each of the GRIN optical elements 7a intersects the optical axis of the lens, and light rays from the on-axis far point source passing through the GRIN optical elements 7a forming the inner ring 9a are guided so that a small spot size of unfocused light is formed at the base power surface 13. This can improve the quality of the image formed at the retina of the lens wearer.

[0107] The GRIN optical elements 7b forming the outer ring 9b all have the same refractive index variation as the GRIN elements 7a forming the inner ring 9a (eg Figure 2A and 2E ). The GRIN optical elements 7a forming the outer ring 9b are all positioned at the same radial distance from the optical axis 2 and the film axis 3 of the lens 5, and at a greater radial distance from the optical axis 2 and the film axis 3 than the GRIN optical elements 7a forming the inner ring 9a.

[0108] GRIN optical elements 7b are arranged in a circle centered on the optical axis 2 of the lens 5 coinciding with the film axis 3. It has the function of focusing light from a distant point source on the axis passing through the GRIN optical element 7b to form focal points 19a, 19b ( Figure 2E 9a). The ring of foci 19a, 19b will have a larger radius than the ring of foci 15a, 15b formed by light passing through the inner ring 9a of the GRIN optical element 7a. The refractive index profile of the GRIN optical element 7b forming the outer ring 9b is the same as the refractive index profile of the GRIN optical element 7a forming the inner ring 9a. When the lens 5 is worn by the wearer, the GRIN optical element 7b forming the outer ring 9b will focus the light toward the same additional power focal plane 17 as the GRIN element 7a forming the inner ring 9a. The local optical axis of each of the GRIN optical elements 7b intersects the optical axis 2 and the membrane axis 3 of the lens 5, and light rays from on-axis distant point sources passing through the GRIN optical element 7b forming the outer ring 9b are guided so that a small spot size of unfocused light is formed at the base power surface 13. This can improve the quality of the image formed at the retina of the lens wearer.

[0109] Figure 3 13 is a flow chart showing a method 1300 for manufacturing an ophthalmic lens using a grayscale image according to an embodiment of the present disclosure. In a first step 1301, a design of a film containing a pattern of GRIN optical elements having an asymmetric refractive index distribution is generated. The desired pattern containing GRIN optical elements is designed. In a second step 1302, a grayscale image is created using the pattern. In a third step 1303, the desired asymmetric refractive index distribution of each GRIN optical element is modeled. In the third step, an ophthalmic lens 1304 is provided, and in a fourth step, a photocurable film 1305 is provided. The grayscale image is used to provide a template for projecting light from a digital light projection system onto the film. The grayscale image masks some areas of the film so that these areas are not exposed to light, while allowing other areas to be exposed to light. The areas of the film exposed to the light from the DLP system will be photocured to produce GRIN optical elements having an asymmetric refractive index distribution. Therefore, in step five 1307, at least one photocured GRIN element is produced inside the photocurable film using the DLP and the grayscale image. In a final step 1309, the film is applied to the surface of the lens substrate.

[0110] Figure 4 is a grayscale image 411 that can be used in a method according to an embodiment of the present disclosure. Dark areas 413 of the grayscale image 411 indicate areas that will not be exposed to light. Brighter areas 415 of the grayscale image 411 indicate areas that will allow light to pass through. The areas of the film exposed to light will be photocured to produce a photocured GRIN optical element.

[0111] Figure 5A 5 is a schematic diagram 517 of a grid used to define desired locations for photocured GRIN optical elements in a method according to an embodiment of the present disclosure. The grid has a triangular grid pattern. Each grid point 510 defines a location on the photocurable film where a GRIN optical element is to be created. The grid pattern is used to generate a grayscale image 511 that includes lighter areas 515 indicating areas where light will be allowed to pass through at each grid point, and darker areas 513 that will not be exposed to light, such as Figure 5B As shown in .

[0112] Figure 6 is a two-dimensional slice 612 taken through a modeled refractive index profile of a GRIN optical element having an asymmetric refractive index profile. The GRIN element has a varying refractive index defined by an asymmetric polynomial function in 3 dimensions (for simplicity, Figure 6 2D slices are shown in Figure ).

[0113] Figure 7 700 is a flowchart showing the steps of converting a modeled desired refractive index profile into a light intensity map for use in a method according to an embodiment of the present disclosure. The flowchart is derived from a modeled refractive index profile of a GRIN element (which is similar to Figure 6 712 ). A refractive index change versus intensity response plot 719 is used to characterize the exposure required to produce a specific refractive index change for a specific film and DLP system. Using this plot 719 and the modeled refractive index distribution, a digital light projection intensity map 721 can be generated, which is a pixel matrix for a DLP system. Figure 7 , a 2D slice through this intensity map 721 is shown. This is used to generate a grayscale image 711, which contains the desired exposure conditions for use in a DLP system. The grayscale image 711 can then be used to expose the photocurable film to light from the DLP to control the pattern of exposure the film experiences. A photocured GRIN optical element with an asymmetric refractive index profile will be produced on the surface of the film.

[0114] Fig. 8A is a top view of an ophthalmic lens 205 manufactured using a method according to an embodiment of the present disclosure. Figure 8B yes Fig. 8A205 is a cross-sectional side view of a lens 205 shown in . The lens 205 has a film 201 having a base refractive index, which is adhered to the front surface of the lens 205 by an adhesive. The film 201 spans a central region of the lens 205. The central region of the lens 205 is surrounded by a peripheral region 204. The film 201 includes a plurality of GRIN optical elements 207 that are photocured using a method according to an embodiment of the present disclosure. The GRIN optical elements 207 are randomly distributed across the surface of the film 201 and extend through the thickness of the film 201. The GRIN optical elements 207 each have a refractive index gradient that varies in a plane perpendicular to the optical axis 202 of the lens 205, in a circumferential direction around the element, and in a radial direction extending outward from the center of the element. Each element 207 has the same refractive index variation. The base refractive index of the film 201 is constant, and the film 201 has a uniform thickness.

[0115] Fig. 9 3 is a front view of a pair of glasses 325 manufactured according to the method of the present disclosure. A pair of glasses 325 contains two lenses 305. Each lens 305 is centered on an optical axis 302 and includes a film 301 disposed on the front surface of the lens 305. The base refractive index of the film 301 is uniform, and the film 301 has a uniform thickness. The film 301 covers the front surface of the lens 305. Light from an on-axis distant point source passing through the film 301 will be focused to a point of light on the optical axis 302 of the lens 305 at the base refractive power focal plane (not shown).

[0116] Each film 301 includes a plurality of GRIN optical elements 307a, 307b arranged in concentric circles 309a, 309b (dashed lines are provided as a guide to the eye and do not represent structural features of the lens 305). Each of the GRIN optical elements 307a, 307b has a refractive index profile that varies in both radial and lateral directions across the elements 307a, 307b parallel to the plane of the film 301, resulting in an asymmetric profile. The GRIN elements 307a forming the inner circle 309a all have the same refractive index variation and are all positioned at the same radial distance from the optical axis 302 of the lens 305. Because the GRIN elements 307a have an asymmetric refractive index profile, light from an on-axis distant point source that passes through the GRIN optical element 307a will be focused away from the optical axis 302. The GRIN optical elements 307a are arranged in a circle centered on the optical axis 302 of each mirror 305, and light from a distant point source passing through the GRIN optical elements 307a forming the inner ring 309a will form a ring of focal points.

[0117] The GRIN optical elements 307b forming the outer ring 309b also all have the same refractive index variation, but these elements 307b have a different refractive index variation than the GRIN optical elements 307a forming the inner ring 309a. The GRIN optical elements 307b forming the outer ring 309b are all positioned at the same radial distance from the optical axis 302 of the lens, and at a greater radial distance from the optical axis 302 than the GRIN optical elements 307a forming the inner ring 309a. Light from a distant point source on the axis passing through the GRIN optical elements 307b forming the outer ring 309b will form a ring of focal points. This ring of focal points will have a larger radius than the ring of focal points formed by light passing through the inner ring 309a of the GRIN optical elements 307a. The refractive index profile of the GRIN optical elements 307b forming the outer ring 309b is different from the refractive index profile of the GRIN optical elements 307a forming the inner ring 309a. When the lens 305 is worn by a wearer, light passing through the GRIN optical elements 307a forming the inner ring 309a will be focused to a point on a first focal plane, and light passing through the GRIN optical elements 307b forming the outer ring 309b will be focused to a point at a second, different focal plane. When the lens 305 is worn by the lens wearer, both the first and second focal planes will be closer to the back surface of the lens 305 than the base power focal plane.

[0118] Although the present disclosure has been described and illustrated with reference to specific example embodiments, those skilled in the art will appreciate that the present disclosure lends itself to many different variations not explicitly described herein. By way of example only, specific possible variations will now be described.

[0119] In the example embodiments of the present disclosure described above, each GRIN element has a refractive index profile that results in a higher power than the base refractive index of the lens. In other example embodiments, the GRIN elements may have a refractive index profile that results in a lower power than the base refractive index of the lens.

[0120] In the example embodiments described above, the film is applied to a surface of a lens (ie, the lens substrate forms part of, or is, the lens). In other embodiments, the layer may be applied to a substrate, which may then be applied to a surface of the lens.

[0121] Although in the foregoing description, integers or elements with known obvious or foreseeable equivalents are mentioned, such equivalents are incorporated herein as if individually set forth. 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 will also understand that integers or features of the present disclosure that are described as advantageous, convenient, or the like are selected and do not limit the scope of the independent technical solutions. In addition, it should be understood that such selected integers or features, while having possible benefits in some embodiments of the present disclosure, may not be desired and therefore may not exist in other embodiments.

Claims

1. A method of manufacturing an ophthalmic lens, comprising: providing a lens substrate; providing a photocurable film; photocuring at least one region of the film using a digital light projection system, thereby producing at least one photocured gradient index optical element having an asymmetric refractive index profile; and The film is applied to the surface of the lens substrate. 2 . The method of claim 1 , wherein using the digital light projection system comprises using a grayscale image to control projection of light from the system onto the film.

3. The method according to claim 2, wherein the method comprises: generating a design for the film, wherein the design comprises a desired pattern of photocured gradient index optical elements; and The grayscale image is generated using the design.

4. The method of claim 3, wherein the desired pattern of photocured gradient refractive index optical elements comprises at least one annular ring of photocured gradient refractive index optical elements.

5. The method of claim 4, wherein the desired pattern of photocured gradient refractive index optical elements comprises a plurality of concentric annular rings of photocured gradient refractive index optical elements.

6. A method according to any preceding claim, wherein the method comprises: modeling a desired asymmetric refractive index distribution for each of the at least one photocured gradient refractive index optical element; and determining at least one exposure condition required to produce the desired asymmetric refractive index distribution.

7. The method of claim 6, wherein the modeled desired refractive index profile of each of the at least one photocured gradient index optical element is defined by an asymmetric polynomial function.

8. The method of claim 7, wherein the modeling a desired refractive index profile results in an asymmetric refractive index profile that varies along a radial direction in a plane parallel to a surface of the film.

9. The method of claim 7 or claim 8, wherein the modeling of a desired refractive index profile results in an asymmetric refractive index profile that varies in at least one linear direction parallel to the surface of the film.

10. The method of claim 7 or claim 8, wherein the modeling of the desired refractive index profile results in an asymmetric refractive index profile that varies along a circumferential direction in a plane parallel to the surface of the film.

11. The method of claim 7 or claim 8, wherein the modeling step comprises modeling at least two different desired refractive index profiles for at least two different photocured gradient index optical elements.

12. A method according to claim 7 or claim 8, when appended to any one of claims 3 to 5, wherein the modeling step includes selecting a desired refractive index distribution of the elements depending on the position of each of the at least one photocured gradient refractive index optical elements within the desired pattern.

13. A method according to claim 7 or claim 8, wherein the modelling step comprises measuring or mapping the variation of the refractive index as a function of exposure conditions.

14. The method of claim 13, wherein the modeling step comprises converting the refractive index variation map into a digital light projection intensity map for controlling the light projection onto the film.

15. The method according to claim 14, comprising: determining whether the digital light projection system produces a significant nonlinear response; and incorporating any significant non-linear responses into the digital light projection intensity map.

16. The method of claim 7 or claim 8, wherein the desired refractive index profile of each of the at least one photocured gradient index optical element produces a photocured gradient index optical element having a diameter or width between 1 μm and 5 mm.

17. The method of any one of claims 1 to 5, wherein the digital light projection system comprises a digital mirror device.

18. The method of any one of claims 1 to 5, wherein the digital light projection system has an illumination wavelength between 440 nm and 660 nm.

19. The method of any one of claims 1 to 5, wherein the digital light projection system has a pixel resolution of less than 100 μm.

20. The method of any one of claims 1-5, wherein the film is applied to the surface of the lens substrate after producing the at least one photocured gradient index optical element.

21. The method of any one of claims 1 to 5, wherein applying the film to the surface of the lens substrate comprises: The film is adhered to the lens substrate using an adhesive.

22. The method of any one of claims 1 to 5, comprising cutting or shaping the film to be suitable for application to the ophthalmic lens.

23. The method of any one of claims 1-5, wherein the ophthalmic lens is a spectacle lens.

24. The method of any one of claims 1-5, wherein the ophthalmic lens is a contact lens.

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