Ophthalmic lens with light scattering for treating myopia

Abstract

An ophthalmic lens, the ophthalmic lens comprising: a lens material having two opposing curved surfaces that define a lens axis; and a light scattering region surrounding an aperture for light passage. The aperture for light passage and the light scattering region are substantially centered on the lens axis, and the light scattering region has a plurality of spaced-apart scattering centers (e.g., on the lens surface and / or embedded in the lens material), sized and shaped to scatter incident light, and the scattering centers are arranged in a pattern that includes random variations in the spacing between adjacent points and / or random variations in the point size.

Description

[0001] Cross - reference to related applications

[0002] This application claims priority to Provisional Application No. 62 / 624,038, filed on January 30, 2018, entitled "Method for Forming Ophthalmic Lenses for the Treatment of Myopia", Provisional Application No. 62 / 663,938, filed on April 27, 2018, entitled "Ophthalmic Lenses with Light Scattering for the Treatment of Myopia", and Provisional Application No. 62 / 671,992, filed on May 15, 2018, entitled "Ophthalmic Lenses with Light Scattering for the Treatment of Myopia". The entire content of each of these provisional applications is incorporated herein by reference. Technical field

[0003] The present invention features an ophthalmic lens for treating myopia and reducing myopia progression. Background art

[0004] The eye is an optical sensor in which light from an external source is focused by the lens onto the surface of the retina (a wavelength - dependent array of photoreceptors). Each of the various shapes that the eye lens can assume is associated with a focal length at which external light is optimally or nearly optimally focused to produce an inverted image on the retina surface corresponding to the external image observed by the eye. In each of the various shapes that the eye lens can assume, the eye lens optimally or nearly optimally focuses light emitted or reflected by external objects within a certain distance range from the eye, and less desirably or fails to focus objects beyond that distance range.

[0005] In an individual with normal vision, the axial length of the eye, or the distance from the lens to the retina surface, corresponds to the focal length for near - optimal focusing of distant objects. An eye of an individual with normal vision focuses on distant objects without neural input to the muscles that exert force to change the shape of the eye lens, a process called "accommodation". As a result of accommodation, a normal individual focuses on nearer nearby objects.

[0006] However, many people suffer from eye - length - related disorders such as myopia ("nearsightness"). In a myopic individual, the axial length of the eye is longer than the axial length required to focus distant objects without accommodation. As a result, a myopic individual can see nearby objects clearly, but distant objects are blurry. Although myopic individuals can usually accommodate, the average distance at which they can focus on an object is shorter than that of an individual with normal vision.

[0007] Typically, a baby is born farsighted, with an eye length shorter than the length required to optimally or nearly optimally focus on distant objects without accommodation. During the normal development of the eye (termed "emmetropization"), the axial length of the eye increases relative to the other dimensions of the eye to a length that provides nearly optimal focusing of distant objects without accommodation. Ideally, as the eye grows to its final adult size, the biological process maintains a nearly optimal relative eye length for the eye size. However, in myopic individuals, the relative eye axial length for the overall eye size continues to increase during development beyond the length that provides nearly optimal focusing of distant objects, resulting in the progression of myopia becoming increasingly evident.

[0008] It is believed that myopia is influenced by both behavioral factors and genetic factors. Thus, myopia can be mitigated by treatment devices that address the behavioral factors. For example, treatment devices for treating diseases related to eye length, including myopia, are described in U.S. Patent Publication No. 2011 / 0313058A1. SUMMARY OF THE INVENTION

[0009] Glasses and contact lenses are disclosed that reduce signals in the retina responsible for eye length growth. Exemplary embodiments are fabricated using, for example, polycarbonate or Trivex lens blanks that are processed by applying a pattern of scattering centers or "dots" that have a dot-free aperture on the visual axis. The result is a reduction in the contrast of the retinal image, which is believed to reduce eye growth associated with myopia development. The dot-free aperture on the lens axis allows the user to experience maximum visual acuity when viewing objects on the axis, while viewing objects in the periphery of the user's visual field with reduced contrast and acuity.

[0010] For these glasses, the contrast of the focused image is reduced in the peripheral region of the retina compared to an image typically used to correct (but not treat) refractive errors. The exact amount of contrast reduction depends on the relative amounts of dark and light regions in the transmitted image. For the example above, with 24% uniform dispersion of light, the maximum contrast reduction would be 48%, where contrast is defined as the illuminance difference / average illuminance. Experiments have demonstrated that this amount of contrast reduction in the peripheral region of the retina has a significant effect on the eye physiology related to the mechanism responsible for controlling eye length growth.

[0011] Aspects of the present invention are summarized as follows:

[0012] Generally, in a first aspect, the present invention features an ophthalmic lens that includes a lens material having two opposing curved surfaces; and a scattering region surrounding the light-transmitting aperture, wherein the scattering region has a plurality of spaced-apart scattering centers sized and shaped to scatter incident light, and the scattering centers are arranged in a pattern that includes an irregular variation in the spacing between adjacent scattering centers and / or an irregular variation in the size of the scattering centers.

[0013] Embodiments of the ophthalmic lens may include one or more of the following features and / or features of other aspects. For example, the scattering centers may be placed relative to a regular array of lattice sites, where each scattering center is offset from a corresponding one of the lattice sites by an amount equal to or less than the jitter amplitude in at least one dimension (e.g., the x and / or y directions), and the jitter amplitude is a fraction of the distance between adjacent lattice sites. The jitter amplitude may be 0.5 or less (e.g., 0.01 to 0.5, 0.02 or greater, 0.03 or greater, 0.04 or greater, 0.05 or greater, 0.08 or greater, 0.1 or greater, 0.12 or greater, 0.15 or greater, 0.18 or greater, 0.2 or greater, 0.25 or greater, 0.3 or greater, 0.35 or greater, 0.4 or greater).

[0014] The scattering centers may have dimensions that vary randomly from a nominal value, and the random variation is equal to or less than the jitter amplitude. The jitter amplitude may be 0.5 times or less of the nominal value (e.g., 0.01 to 0.5, 0.02 or greater, 0.03 or greater, 0.04 or greater, 0.05 or greater, 0.08 or greater, 0.1 or greater, 0.12 or greater, 0.15 or greater, 0.18 or greater, 0.2 or greater, 0.25 or greater, 0.3 or greater, 0.35 or greater, 0.4 or greater).

[0015] The scattering centers may have volumes that vary randomly from a nominal volume, and the random variation is equal to or less than the jitter amplitude. The jitter amplitude may be 0.5 times or less of the nominal volume (e.g., 0.01 to 0.5, 0.02 or greater, 0.03 or greater, 0.04 or greater, 0.05 or greater, 0.08 or greater, 0.1 or greater, 0.12 or greater, 0.15 or greater, 0.18 or greater, 0.2 or greater, 0.25 or greater, 0.3 or greater, 0.35 or greater, 0.4 or greater).

[0016] The lens may have a lens axis, and the aperture and the annular region are substantially centered on the lens axis.

[0017] The scattering region may include a first scattering region and a second scattering region, the second scattering region being disposed between the light-transmitting aperture and the first scattering region. The second scattering region includes scattering centers, the size and arrangement of which are such that the incident light is scattered less strongly than the scattering centers of the first scattering region. The lens may have a lens axis, and the aperture as well as the first and second scattering regions are substantially centered on the lens axis, and the scattering centers in the second scattering region have sizes that increase monotonically (e.g., linearly or geometrically) with increasing radial distance from the lens axis. The lens may have a lens axis, and the aperture as well as the first and second scattering regions are substantially centered on the lens axis, and the scattering centers in the second scattering region have sizes and / or volumes that vary monotonically (e.g., linearly or geometrically) with increasing radial distance from the lens axis.

[0018] An irregular variation in the scattering center spacing may be a random variation. An irregular variation in the scattering center size may be a random variation.

[0019] The spacing between the scattering centers and / or the size of the scattering centers may be varied to encode information into the scattering centers.

[0020] The scattering centers may be of a substantially circular shape. The shape of the scattering centers may be a logo or an alphanumeric symbol.

[0021] The lens may be a plano lens, a single vision lens or a multifocal lens. The lens may be an ophthalmic lens for glasses or a contact lens.

[0022] The scattering region may be an annular region. The light-transmitting aperture may be a circular aperture.

[0023] In another aspect, the present invention features a method for treating a disease related to eye length, comprising: identifying a disease related to eye length in a patient; and using an ophthalmic lens according to the prior art to reduce the contrast of an image in the visual periphery of the patient.

[0024] In another aspect, the present invention features a pair of glasses, comprising: a glasses frame; and a pair of ophthalmic lenses according to the above aspects respectively mounted in the frame.

[0025] Embodiments of the glasses may include one or more of the following features and / or features of other aspects. For example, the dot pattern may reduce the image contrast of an object viewed through the dot pattern by at least 30% (e.g., at least 35%, at least 40%, at least 45%, at least 50%, at least 55%, at least 60%, up to 80%) compared to the image contrast of an object viewed through the light-transmitting aperture.

[0026] The lens may have a dioptric power to correct the wearer's on-axis vision to 20 / 20 or better through the clear aperture, and for at least a portion of the wearer's peripheral vision through the dot pattern, the lens may correct the wearer's vision to 20 / 25 or better.

[0027] In another aspect, the invention features a method of treating a disease related to eye length, including identifying a disease related to eye length in a patient; and using the glasses described above to reduce the contrast of images in the visual periphery of the patient.

[0028] Generally, in another aspect, the invention features a method including: focusing a laser beam to a focal point; exposing an ophthalmic lens to the focused laser radiation to form optical scattering features in a pattern on the surface of the ophthalmic lens. Exposing the ophthalmic lens includes causing relative movement between the laser beam and the lens such that different positions on the lens surface intersect the laser beam at different positions relative to the focal point.

[0029] The implementation of the method may include one or more of the following features and / or features of other aspects. For example, the optical scattering features formed by the laser beam may vary according to the position of the lens surface relative to the focal point. As the distance of the lens surface from the focal point increases, the degree of scattering caused by the optical scattering features may decrease.

[0030] The pattern may include an annular region of optical scattering features that surrounds the clear aperture corresponding to the viewing axis of the ophthalmic lens. The optical scattering features may include discrete points. The points may be arranged in an array, each point spaced apart by a distance of 1 mm or less, and the maximum size of each point is 0.5 mm or less. The clear aperture may be a region without points, having a maximum size greater than 1 mm.

[0031] The laser may be an infrared laser. The laser may be a CO2 laser.

[0032] The ophthalmic lens may be exposed to pulsed laser radiation.

[0033] The laser may have sufficient energy to remove lens material from the lens surface.

[0034] The laser may have a power in the range of 0.5 W to 60 W.

[0035] During the exposure, the laser radiation may be focused to a spot size of about 0.1 mm or less (e.g., about 0.05 mm or less, about 0.025 mm or less).

[0036] The ophthalmic lens may be exposed such that each position exposed on the lens surface undergoes a corresponding discrete exposure of the same duration and the same energy.

[0037] The exposed surface can be a convex surface or a concave surface.

[0038] Generally, in another aspect, the present invention features a method of forming scattering centers in an ophthalmic lens, the method comprising: exposing a region of the ophthalmic lens to laser radiation having a wavelength and power sufficient to cause foaming of the material of the ophthalmic lens. Bubbles from the foaming form scattering centers in the ophthalmic lens. The implementation of the method may include one or more features of other aspects.

[0039] Generally, in another aspect, the present invention features a method comprising: simultaneously exposing an ophthalmic lens formed of lens material to two or more laser radiation beams such that the two or more beams overlap in a portion of the lens material, and the intensity of the laser radiation in the overlapping beams is sufficient to form an optical scattering feature in the lens material; and varying the position of the overlapping beams in the lens to form a pattern of optical scattering features in the lens.

[0040] The implementation of the method may include one or more of the following features and / or features of other aspects. For example, the laser intensity of a single beam among the two or more beams may not be sufficient to form an optical scattering feature in the lens material in an exposure to the laser beam of less than 10 seconds.

[0041] The laser radiation in the overlapping beams may interact with the lens material to change the refractive index of the lens material.

[0042] The laser radiation in the overlapping beams may change the refractive index of the lens material by causing a photochemical change in the lens material.

[0043] The laser radiation in the overlapping beams may change the refractive index of the lens material by causing a photothermal change in the lens material.

[0044] In another aspect, the present invention features a pair of glasses comprising a spectacle frame and a pair of ophthalmic lenses mounted in the frame, each lens including a pattern distributed on each lens formed using one of the above methods.

[0045] Embodiments of the glasses may include one or more of the following features and / or features of other aspects. For example, each pattern may include a region that includes an optical scattering feature that surrounds a light-transmitting aperture that has no scattering feature. A dot pattern may reduce the image contrast of an object viewed through the dot pattern by at least 30% (e.g., at least 35%, at least 40%, at least 45%, at least 50%, at least 55%, at least 60%) compared to the image contrast of the object viewed through the light-transmitting aperture.

[0046] The lens can have a refractive power to correct the wearer's on-axis vision to 20 / 20 or better through the clear aperture, and for at least a portion of the wearer's peripheral vision through the dot pattern, the lens can correct the wearer's vision to 20 / 25 or better.

[0047] Among other advantages, the disclosed embodiments are characterized by glasses that include the following features: reducing the signals in the retina responsible for eye length growth in both eyes on the lens without reducing the user's on-axis vision in either eye to a disruptive level for the user. For example, a dot pattern is provided that moderately blurs the wearer's peripheral vision while allowing normal on-axis viewing through the clear aperture, enabling the wearer to use it all day, every day. Compared to methods involving alternating between different pairs of glasses or using glasses accessories, the disclosed embodiments can also provide therapeutic benefits for users of both eyes with just one pair of glasses.

[0048] In addition, the dot pattern may be substantially unnoticed by others, especially in the case where the dot pattern is transparent and colorless and / or contact lenses are used. The subtlety of the dot pattern can lead to more consistent use by certain wearers, especially children, who might otherwise be self-conscious when using more conspicuous devices on a daily basis (e.g., at school or among peers). For example, a gradient dot pattern can be used to reduce the conspicuity of the dot pattern to third parties.

[0049] The dot pattern can also be optimized to improve the observer's comfort. For example, the dot pattern can have a transition zone that can smooth the transition from the clear aperture of the lens to the scattering zone in the observer's field of view. Alternatively or additionally, random dithering can be applied to the dot pattern (e.g., to dot size and / or dot spacing). Such randomization can reduce the undesirable optical effects associated with a uniform array of optical features (e.g., diffraction effects or interference effects). For example, random dithering can be used to reduce the glare experience of the user. The conspicuity of the dot pattern to third parties can also be reduced by reducing diffraction or interference effects in reflections.

[0050] Information can be encoded into the dot pattern. For example, the dots can be shaped as symbols (e.g., alphanumeric symbols) or logos. Alternatively or additionally, the shape, size, and / or spacing of the dots can be changed according to a key for embedding information into the dot pattern.

[0051] The disclosed embodiments can allow for the effective and economical formation of a dot pattern for mitigating eye elongation on a conventional ophthalmic lens, for example, by forming the dot pattern on the surface or block of the lens. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] Figure 1A A pair of glasses containing an ophthalmic lens for treating myopia is shown.

[0053] Figure 1B shows Figure 1A a dot pattern on the ophthalmic lens shown

[0054] Figure 2 shows the contrast reduction experienced using an exemplary ophthalmic lens for treating myopia

[0055] Figure 3A shows a cross - sectional view of an exemplary lens material removed from the surface of the lens

[0056] Figure 3B shows a cross - sectional view of an exemplary lens having scattering inclusions between opposite surfaces of the lens

[0057] Figure 4A and Figure 4B shows a lens blank having a dot pattern with a transition zone between the clear aperture and the dot pattern

[0058] Figure 4C shows dots having a random displacement from a uniform spacing

[0059] Figure 5A shows an exemplary dot pattern having a transition zone and dots with a uniform spacing

[0060] Figure 5B shows an exemplary dot pattern having a transition zone and dots having a random displacement from a uniform spacing

[0061] Figure 5C shows another exemplary dot pattern having a transition zone and dots with a uniform spacing

[0062] Figure 5D shows another exemplary dot pattern having a transition zone and dots having a random displacement from a uniform spacing

[0063] Figure 5E shows yet another exemplary dot pattern having a transition zone and dots with a uniform spacing

[0064] Figure 5F shows yet another exemplary dot pattern having a transition zone and dots having a random displacement from a uniform spacing

[0065] Figure 6A shows an exemplary lens having a graded dot pattern with different spacings between adjacent dots

[0066] Figure 6B shows an exemplary lens having a graded dot pattern with varying dot sizes

[0067] Figure 7AAn exemplary lens with a pattern is shown, the pattern having information encoded by dots of varying size.

[0068] Figure 7B An exemplary lens with a pattern is shown, the pattern having information encoded by dots of different shapes.

[0069] Figure 7C An exemplary lens is shown having a pattern formed by dots in the form of a logo.

[0070] Figure 8 An exemplary machine-readable system is shown.

[0071] Figure 9 is a schematic diagram of a laser system for forming recesses on the surface of a lens.

[0072] Figure 10 is a schematic diagram of another laser system for forming recesses on the surface of a lens.

[0073] Figure 11A is a graph of the refractive index change of a lens material versus laser intensity.

[0074] Figure 11B is a schematic diagram of a laser system for forming inclusions in the bulk material of an exemplary lens. Detailed Description

[0075] Referring to Figure 1A , glasses 100 for reducing myopia are disclosed, which allow simultaneous treatment of both eyes with substantially no impairment of clear vision. In addition, the glasses are strong enough and unobtrusive so that the wearer can perform the same daily activities without the glasses malfunctioning and without being self-conscious about their appearance, which is particularly desirable since glasses are commonly used to prevent eye elongation in children.

[0076] The glasses 100 for reducing myopia consist of a pair of frames 101 and ophthalmic lenses 110a and 110b mounted in the frames. Typically, the ophthalmic lenses can be plano lenses, single vision lenses (e.g., with positive or negative optical power), or multifocal lenses (e.g., bifocal or progressive lenses). The ophthalmic lenses 110a and 110b each have light-transmitting apertures 120a and 120b respectively surrounded by contrast-reducing regions 130a and 130b. The light-transmitting apertures 120a and 120b are positioned to coincide with the wearer's on-axis viewing positions, while the contrast-reducing regions 130a and 130b correspond to the wearer's peripheral vision. Also referring to Figure 1B, the contrast - reducing regions 130a and 130b consist of an array of dots 140 that reduce the contrast of objects in the wearer's peripheral vision by scattering light passing through those regions into the wearer's eyes. Typically, the dots 140 can be provided by forming protrusions and / or depressions on one or both surfaces of each lens in regions 130a and 130b, and / or by forming scattering inclusions within the lens material itself in these regions.

[0077] The size and shape of the light - passing aperture may vary. Generally, the light - passing aperture provides a visual cone for the wearer, and their visual acuity can be optimally corrected for it (e.g., to 20 / 15 or 20 / 20). In some embodiments, the maximum dimension of the aperture (in the x - y plane) is in the range of about 0.2 mm (e.g., about 0.3 mm or greater, about 0.4 mm or greater, about 0.5 mm or greater, about 0.6 mm or greater, about 0.7 mm or greater, about 0.8 mm or greater, about 0.9 mm or greater) to about 1.5 cm (e.g., about 1.4 cm or less, about 1.3 cm or less, about 1.2 cm or less, about 1.1 cm or less, about 1 cm or less). In the case where the aperture is circular, for example, as Figure 1A shown, this dimension corresponds to the diameter of the circle (i.e., A x = A y ), but non - circular (e.g., elliptical, polygonal, A x ≠A y ) apertures can also be used.

[0078] Within the observer's field of view, the light - passing aperture can subtend a solid angle of about 30 degrees or less (e.g., about 25 degrees or less, about 20 degrees or less, about 15 degrees or less, about 12 degrees or less, about 10 degrees or less, about 9 degrees or less, about 8 degrees or less, about 7 degrees or less, about 6 degrees or less, about 5 degrees or less, about 4 degrees or less, about 3 degrees or less). The solid angles subtended in the horizontal and vertical visual planes can be the same or different.

[0079] Generally, the dot patterns in the contrast-reducing regions 130a and 130b can be selected based on a variety of design parameters to provide a desired degree of light scattering on the user's retina. Generally, these design parameters include, for example, dot density, its size and shape, and its refractive index, and these parameters will be discussed in more detail below. Ideally, the dot pattern is selected to provide high visual acuity on the fovea and reduced image contrast on other parts of the retina, and low enough discomfort to the wearer to allow for long-term, continuous wear. For example, for children, it may be desirable to be able to wear the glasses comfortably for most, if not all, of the day. Alternatively or additionally, the dot pattern can be designed for specific tasks, especially tasks that are thought to strongly promote eye length growth, such as video games, reading, or other wide-angle, high-contrast image exposures. For example, in such cases (e.g., where the user experiences high contrast in their peripheral vision and / or where the wearer does not need to use their peripheral vision to move and orient themselves), the scattering intensity and scattering angle in the periphery may increase, while considerations of awareness and self-esteem may decrease. This can result in higher efficiency of reducing peripheral contrast in such high-contrast environments.

[0080] It can be considered that reducing the image contrast on the fovea of the user's eye is less efficient in controlling eye growth compared to reducing the image contrast on other parts of the user's retina. Therefore, the dot pattern can be customized to reduce (e.g., minimize) the light scattered into the user's fovea, while relatively more light on other parts of the retina is scattered light. The amount of scattered light on the fovea can be affected by the size of the light-transmitting apertures 120a and 120b, respectively, but also by the nature of the dots, especially the nature of the dots closest to the light-transmitting apertures. For example, in some embodiments, the dots closest to the light-transmitting apertures can be designed to have lower scattering efficiency than the more distant dots. Alternatively or additionally, in some embodiments, the dots closest to the light-transmitting apertures can be designed to have a smaller angle of forward scattering compared to the dots farther from the aperture.

[0081] In certain embodiments, the dots can be designed to transmit reduced narrow-angle scattering and increased wide-angle scattering to create a uniform light distribution / low-contrast signal on the retina while maintaining acuity through the geometry of the scattering centers. For example, the dots can be designed to generate significant wide-angle forward scattering (e.g., such as greater than 10%, 20% or more, 30% or more, 40% or more, 50% or more, deflected more than 2.5 degrees). The narrow-angle forward scattering (i.e., within 2.5 degrees) can be kept relatively low (e.g., 50% or lower, 40% or lower, 30% or lower, 20% or lower).

[0082] Generally, various different metrics can be used to evaluate the performance of a dot pattern to optimize the dot pattern for glasses for reducing myopia. For example, the dot pattern can be empirically optimized based on physical measurements of lenses having different dot patterns. For example, light scattering can be characterized based on haze measurements (such as international test standards for haze (e.g., ASTM D1003 and BS EN ISO13468)). Conventional haze meters can be used, such as BYK-Gardner haze meters (such as the Haze-GardPlus instrument), which measure the total amount of light transmitted through the lens, the amount of undisturbed transmitted light (e.g., within 0.5 degrees), the amount of light deflected more than 2.5 degrees, and clarity (amount within 2.5 degrees). To empirically optimize the scattering pattern, other devices can also be used to characterize light scattering. For example, a device that measures light diffusion by measuring the light in an annulus around about 2.5 degrees (e.g., a device from Hornell) can be used.

[0083] Alternatively or additionally, the dot pattern can be optimized by computer modeling software (e.g., Zemax or Code V).

[0084] In some embodiments, the dot pattern can be designed based on the optimization of the point spread function, which is a representation of the image of the scattering centers on the retina. For example, the size, shape, and spacing of the scattering centers can be changed to evenly spread the illumination of the retina so that the retina outside the fovea is evenly covered by scattered light to reduce (e.g., minimize) the contrast in that retinal region.

[0085] Alternatively or additionally, the dot pattern can be designed based on the optimization of the modulation transfer function, which refers to the spatial frequency response of the human visual system. For example, the size, shape, and spacing of the scattering centers can be changed to smooth the attenuation of a range of spatial frequencies. The design parameters of the dot pattern can be changed to increase or decrease certain spatial frequencies as needed. Generally, the spatial frequencies of visual interest are 18 cycles per degree on the fine side and 1.5 cycles per degree on the coarse side. The dot pattern can be designed to provide enhanced signals on certain subsets of spatial frequencies within this range.

[0086] The foregoing metrics can be used to evaluate the dot pattern based on the size and / or shape of the dots, both of which can vary as needed. For example, the dots can be substantially circular (e.g., spherical), elongated (e.g., elliptical), or irregularly shaped. Generally, the size of the protrusions (e.g., as Figure 1BThe diameter shown should be large enough to scatter visible light, but small enough so that it is not distinguishable by the wearer during normal use. For example, the size of the dots (measured in the x-y plane) can range from about 0.001 mm or greater (e.g., about 0.005 mm or greater, about 0.01 mm or greater, about 0.015 mm or greater, about 0.02 mm or greater, about 0.025 mm or greater, about 0.03 mm or greater, about 0.035 mm or greater, about 0.04 mm or greater, about 0.045 mm or greater, about 0.05 mm or greater, about 0.055 mm or greater, about 0.06 mm or greater, about 0.07 mm or greater, about 0.08 mm or greater, about 0.09 mm or greater, about 0.1 mm) to about 1 mm or less (e.g., about 0.9 mm or less, about 0.8 mm or less, about 0.7 mm or less, about 0.6 mm or less, about 0.5 mm or less, about 0.4 mm or less, about 0.3 mm or less, about 0.2 mm or less, about 0.1 mm).

[0087] Note that for smaller dots, such as those having dimensions comparable to the wavelength of light (e.g., 0.001 mm to about 0.05 mm), light scattering can be considered Rayleigh scattering or Mie scattering. For larger protrusions, such as about 0.1 mm or greater, light scattering may be due to geometric scattering.

[0088] Generally, on each lens, the size of the dots can be the same or can vary. For example, the size can increase or decrease according to the position of the protrusion (e.g., as measured from the clear aperture) and / or according to the distance from the edge of the lens. In some embodiments, the protrusion size varies monotonically (e.g., monotonically increasing or monotonically decreasing) with the distance from the center of the lens. In some cases, the monotonic increase / decrease in size includes linearly changing the diameter of the protrusion according to the distance from the center of the lens.

[0089] Figure 1B The dots shown in are arranged on a square grid, spaced equally in each direction. This is shown by D in the y direction y and D in the x direction x shown. Generally, these dots are spaced such that they together provide sufficient contrast reduction in the periphery of the observer to reduce myopia. Typically, a smaller dot spacing will result in a greater contrast reduction (assuming adjacent dots do not overlap or merge). Typically, D x and D yIn the range of from about 0.05 mm (e.g., about 0.1 mm or greater, about 0.15 mm or greater, about 0.2 mm or greater, about 0.25 mm or greater, about 0.3 mm or greater, about 0.35 mm or greater, about 0.4 mm or greater, about 0.45 mm or greater, about 0.5 mm or greater, about 0.55 mm or greater, about 0.6 mm or greater, about 0.65 mm or greater, about 0.7 mm or greater, about 0.75 mm or greater) to about 2 mm (e.g., about 1.9 mm or less, about 1.8 mm or less, about 1.7 mm or less, about 1.6 mm or less, about 1.5 mm or less, about 1.4 mm or less, about 1.3 mm or less, about 1.2 mm or less, about 1.1 mm or less, about 1 mm or less, about 0.9 mm or less, about 0.8 mm or less). As an example, the dot pitch can be 0.55 mm, 0.365 mm, or 0.240 mm.

[0090] Although the dots shown in Figure 1B are arranged at equal intervals in the x - direction and y - direction, more generally, the intervals in each direction can be different. In addition, the protrusions can be arranged in a non - square grid. For example, a hexagonal grid can be used. Non - regular arrays are also possible, for example, random or semi - random dot placement can be used. In the case of a random pattern, the dimensions given will be the average spacing of the dots in the x and y directions.

[0091] Generally, the coverage of the dots on the lens can vary as needed. Here, the coverage refers to the proportion of the total lens area, as projected onto the x - y plane corresponding to the dots. Generally, a lower dot coverage will result in lower scattering than a higher dot coverage (assuming that the individual dots are discrete, i.e., they do not merge to form larger dots). The dot coverage can vary from 10% or more to about 75%. For example, the dot coverage can be 15% or more, 20% or more, 25% or more, 30% or more, 35% or more, 40% or more, 45% or more, such as 50% or 55%). The dot coverage can be selected according to the user's comfort, for example, to provide a sufficient level of peripheral vision comfort so that the wearer will voluntarily wear the glasses for a long time (e.g., all day).

[0092] Although in Figure 1B the dots are depicted as having circular footprints, more generally, the dots can have other shapes. For example, in the case of an elliptical dot, the dot can be elongated in one direction (e.g., in the x - direction or y - direction). In some embodiments, the shape of the dot is random.

[0093] It can be considered that the light from the scene incident on the lens in the regions 130a and 130b with reduced contrast between the points contributes to forming an image of the scene on the user's retina, while the light from the scene incident on the points does not. Additionally, the light incident on the points still transmits to the retina, thus having the effect of reducing the image contrast while substantially not reducing the light intensity at the retina. Therefore, it can be considered that the amount of contrast reduction in the user's peripheral vision is related (e.g., approximately proportional) to the ratio of the surface area of the regions with reduced contrast covered by the points. Generally, the points occupy at least 10% (e.g., 20% or more, 30% or more, 40% or more, 50% or more, such as 90% or less, 80% or less, 70% or less, 60% or less) of the area of the regions 130a and 130b with reduced contrast (as measured in the x - y plane).

[0094] Generally, the dot pattern reduces the contrast of the object image in the wearer's peripheral vision without significantly reducing the observer's visual acuity in that region. Here, peripheral vision refers to the field of view outside the clear aperture field of view. The image contrast in these regions can be reduced by 40% or more (e.g., 45% or more, 50% or more, 60% or more, 70% or more, 80% or more) relative to the image contrast observed using a defined clear aperture. The contrast reduction can be set according to the requirements of each individual case. It can be considered that a typical contrast reduction will be in the range of about 50% to 55%. A contrast reduction below 50% can be used for very mild cases, while subjects with a higher inclination may require a contrast reduction above 55%. The peripheral visual acuity can be corrected to 20 / 30 or better (e.g., 20 / 25 or better, 20 / 20 or better) through subjective refraction while still achieving a meaningful contrast reduction.

[0095] The contrast here refers to the luminance difference between two objects within the same field of view. Therefore, contrast reduction refers to the change in this difference.

[0096] The contrast and contrast reduction can be measured in various ways. In some embodiments, the contrast can be measured based on the luminance difference between different parts (such as a checkerboard of black and white squares) of a standard pattern obtained through the clear aperture and the dot pattern of the lens under controlled conditions.

[0097] Alternatively or additionally, contrast reduction can be determined based on the optical transfer function (OTF) of the lens (see, e.g., http: / / www.montana.edu / jshaw / documents / 18%20EELE582_S15_OTFMTF.pdf). For the OTF, the contrast of the transmission for stimuli is specified, where the bright and dark regions are sinusoidally modulated at different "spatial frequencies". These stimuli look like alternating bright and dark bars, and the spacing between the bars varies within a certain range. For all optical systems, the transmission of the contrast of the sinusoidally varying stimulus with the highest spatial frequency is the lowest. The relationship that describes the transmission of the contrast for all spatial frequencies is the OTF. The OTF can be obtained by performing a Fourier transform on the point spread function. The point spread function can be obtained by imaging a point source passing through the lens onto a detector array and determining how the light from the point is distributed across the entire detector.

[0098] If conflicting measurement results occur, the OTF technique is preferred. In some embodiments, the contrast can be estimated based on the ratio of the area of the lens covered by the point to the area of the clear aperture. In this approximation, it is assumed that all the light hitting the point is evenly spread across the entire retinal area, which reduces the amount of light available in the brighter regions of the image and thus adds light to the darker regions. Therefore, the contrast reduction can be calculated based on the transmission measurements through the clear aperture of the lens and the point pattern.

[0099] Generally, the ophthalmic lenses 110a and 110b can be transparent or colored. That is, the lenses can be optically transparent, appear transparent, and / or colorless for all visible wavelengths, or can include a spectral filter that appears colored. For example, the ophthalmic lens can include a filter that reduces the amount of red light transmitted to the wearer. It is believed that overstimulating the L cone cells in the human eye (especially in children) may lead to non-optimal eye elongation and myopia. Therefore, spectral filtering of red light using an ophthalmic lens can further reduce myopia in the wearer.

[0100] Spectral filtering can be provided by applying a film on the surface of the lens. The film can be applied by physically depositing a material onto the lens surface, coating a layer of material on the surface, or laminating a preformed film onto the surface. Suitable materials include absorptive filter materials (e.g., dyes) or multilayer films that provide interference filtering. In some embodiments, spectral filtering can be provided by including a filter material in the lens material itself and / or in the material used to form the protrusions.

[0101] Reference Figure 2, the effect of spectral filtering and contrast reduction from a dot pattern is shown by viewing black text on a white background using glasses 210. The white background of the text has a green appearance due to the filtering of red wavelengths by the glasses. Image contrast is unaffected at clear apertures 220a and 220b, but is reduced elsewhere in the observer's visual frame.

[0102] As described above, in general, the dots may be provided as protrusions and / or depressions on one or both surfaces of each lens and / or as scattering inclusions in the lens material itself. In some embodiments, the dots may be formed by an array of protrusions on a surface (e.g., the back surface or the front surface) of each of the lenses 110a and 110b.

[0103] The protrusions can be formed from an optically clear material having a similar refractive index to the underlying lens, which is 1.60 for polycarbonate. For example, in embodiments where the lens is formed from polycarbonate, the protrusions can be formed from a polymer having a refractive index similar to PC, such as a light-activated polyurethane or epoxy-based plastic. In addition to PC, the lens itself can also be made from allyl diglycol carbonate plastic, urethane-based monomers, or other impact-resistant monomers. Alternatively, the lens can be made from one of the denser high-index plastics with a refractive index greater than 1.60. In some embodiments, the lens is made from an optically clear material with a lower refractive index (e.g., CR39 is 1.50 and Trivex is 1.53).

[0104] The surface dot pattern can also be formed by creating recesses on one or both surfaces of the lens. Figure 3A , the lens 300 includes a dot pattern formed by recesses 304 formed on the surface of the lens body 302. In this example, a meniscus lens of negative refractive power is depicted. More generally, positive refractive power lenses or lenses with no refractive power may also be used. The recesses 304 may have a size and / or spacing similar to the protrusions described above. The recesses 304 may be formed using a variety of techniques, such as etching (e.g., physical etching or chemical etching) or ablating material from the lens surface (e.g., using laser radiation or a molecular or ion beam). In some embodiments, the recesses are formed when the lens is molded. In some cases, the recesses may respectively correspond to areas of the lens surface in which sufficient material has been removed to roughen the surface so that the lens surface scatters rather than refracts incident light.

[0105] The lens 300 also includes an optical coating 306 on a surface of the lens body 302 opposite the recess 304. The optical coating 306 may perform one or more functions, such as anti-reflection, spectral filtering (eg, UV filtering), and / or a protective hard coating.

[0106] In some embodiments, the contrast reduction is produced by other diffusing structures, such as a rough surface. A holographic diffuser or a ground glass diffuser can be used. In some embodiments, the diffuser can be provided by a film laminated on the lens surface.

[0107] Reference Figure 3B , a cross-sectional view of another lens 310 is shown. The lens includes a lens body 312, and the lens body 312 includes embedded scattering centers 314. The lens 310 also includes an optical coating 316 on one of the surfaces of the lens body. Optical coatings on both surfaces are also possible. The scattering centers are typically formed of a material with a refractive index that does not match that of the bulk lens material. For example, when molding the lens, appropriately sized transparent beads can be dispersed in the lens material, where the refractive index of the bead material and the bulk lens material are different. The clear aperture is formed only by the bulk lens material.

[0108] In some embodiments, a process that selectively induces a refractive index change in the lens bulk material can be used to form the embedded scattering centers 314. For example, exposure to a laser beam causes a local change in the refractive index of the bulk lens material, e.g., through photochemical and / or photothermal interactions. Exemplary laser exposure methods for positioning dot patterns are described in detail below.

[0109] Generally, the refractive index mismatch between the lens material and the dot material affects the amount of light scattered at each protrusion, e.g., as calculated using the point spread function. Generally, the greater the refractive index mismatch between the materials, the more the incident light will be scattered. Thus, the refractive index mismatch can be used as a design parameter to optimize the scattering characteristics of the dots.

[0110] In some embodiments, the protrusion material is selected to have a refractive index (e.g., as measured at one or more wavelengths in the visible light range) within 0.1 of the refractive index of the lens material (e.g., 0.09 or less, 0.08 or less, 0.07 or less, 0.06 or less, 0.05 or less, 0.04 or less, 0.03 or less, 0.02 or less, 0.01 or less, 0.005 or less, 0.002 or less, 0.001 or less).

[0111] In certain embodiments, a larger refractive index mismatch (e.g., greater than 0.1) is possible. For example, the protrusion material can be selected to have a refractive index that differs from the refractive index of the lens material by 0.15 or more (e.g., 0.2 or more, 0.25 or more, 0.3 or more, 0.35 or more, such as up to about 0.4).

[0112] Typically, the refractive index of each point can be the same or different. For example, in the case where each point is formed of the same material, each point can have the same refractive index. Alternatively, in some embodiments, the refractive index can vary between points or between different groups of points. For example, in certain embodiments, the refractive index mismatch between the points and the lens block material can increase as the radial distance from the lens axis increases, so as to increase the amount of light scattering from each point as the radial distance from the lens axis increases.

[0113] In some cases, the points can be formed of a material that absorbs at least some of the light incident thereon, such as a dye. The material can be selected to absorb broadband visible light, or only light of certain wavelengths (e.g., absorb short wavelength components or long wavelength components). It can be considered that the light-absorbing material can help reduce glare and / or provide another design parameter for the point spread function for shaping the points. In some embodiments, exposure to radiation can change the lens material from transparent to absorptive at a specific wavelength. For example, exposure to radiation can burn the lens material so as to form light absorption centers in or on the surface of the lens material.

[0114] As previously mentioned, typically, the size, spacing, and arrangement of the point pattern can vary. In some embodiments, the point pattern is characterized by, for example, a gradient in point size and / or spacing. The point pattern can be characterized by a gradient in the scattering efficiency of the points (e.g., due to a gradient in the refractive index mismatch and / or shape of each point). A graded point pattern can reduce the conspicuity of the pattern. For example, a gradual transition from the transparent part to the scattering part of the lens may not be as conspicuous as a sharp transition.

[0115] In some embodiments, the lens can have features of different regions, where the point pattern varies from region to region. For example, referring to Figure 4A and Figure 4B , lens 400 includes a light transmissive aperture 410, a transition region 420, and a scattering region 430. The light transmissive aperture 410 has a radius R410, and the transition region 420 is an annular region surrounding the light transmissive aperture, and the annular region has an inner diameter R 410 and an outer diameter R 420 . The remainder of the lens region forms the scattering region 430.

[0116] The transition region 420 is characterized by a point pattern that scatters less incident light than the point pattern in the scattering region 430, thereby providing a transition in the scattering characteristics of the lens from the light transmissive aperture to the scattering region. This transition can be advantageous because it reduces the scattering into the fovea compared to the scattering that would be provided if the scattering region extended to the light transmissive aperture. Another advantage is that the transition region can reduce the visibility of the point pattern to the user, thereby providing a more comfortable wearing experience. This is particularly important for children because the likelihood of a child wearing glasses regularly for long periods depends on the child's comfort.

[0117] Typically, the dot pattern in the transition region 420 can vary. In some embodiments, the transition region is characterized by a uniform dot pattern, where the dots have the same shape and size and are evenly spaced. Alternatively, in certain embodiments, the dot pattern in the transition region can be characterized by a varying dot density, spacing, and / or size. For example, the dot pattern can be selected to provide the weakest scattering closest to the clear aperture and monotonically increasing scattering as the radial distance from R 410 to R 420 increases. For example, in some embodiments, the dot density increases monotonically (e.g., linearly) from R 410 to R 420 . By way of example, as the radial distance from the lens axis increases from R 410 to R 420 , the dot diameter can increase linearly from a first value (e.g., 0.05 mm) to a second value (e.g., 0.17 mm). Alternatively or additionally, the dot spacing can decrease monotonically (e.g., linearly) from R 410 to R 420 .

[0118] Typically, R 410 is in the range of about 1 mm to about 3 mm (e.g., 1.0 mm to 1.1 mm, 1.1 mm to 1.2 mm, 1.2 mm to 1.3 mm, 1.3 mm to 1.4 mm, 1.4 mm to 1.5 mm, 1.5 mm to 1.6 mm, 1.6 mm to 1.7 mm, 1.7 mm to 1.8 mm, 1.8 mm to 1.9 mm, 1.9 mm to 2.0 mm, 2.0 mm to 2.1 mm, 2.1 mm to 2.2 mm, 2.2 mm to 2.3 mm, 2.3 mm to 2.4 mm, 2.4 mm to 2.5 mm, 2.5 mm to 2.6 mm, 2.6 mm to 2.7 mm, 2.7 mm to 2.8 mm, 2.8 mm to 2.9 mm, 2.9 mm to 3.0 mm).

[0119] R 420It can be in the range of about 2 mm to about 6 mm (e.g., 2.0 mm to 2.2 mm, 2.2 mm to 2.4 mm, 2.4 mm to 2.6 mm, 2.6 mm to 2.8 mm, 2.8 mm to 3.0 mm, 3.0 mm to 3.2 mm, 3.2 mm to 3.4 mm, 3.4 mm to 3.6 mm, 3.6 mm to 3.8 mm, 3.8 mm to 4.0 mm, 4.0 mm to 4.2 mm, 4.2 mm to 4.4 mm, 4.4 mm to 4.6 mm, 4.6 mm to 4.8 mm (4.8 mm to 5.0 mm, 5.0 mm to 5.2 mm, 5.2 mm to 5.4 mm, 5.4 mm to 5.6 mm, 5.6 mm to 5.8 mm, 5.8 mm to 6.0 mm).

[0120] In some embodiments, the dot pattern includes randomly displaced dots relative to a regular array. Introducing random displacements can reduce optical effects associated with regularly spaced scattering centers (such as starburst glare). See, for example, https: / / www.slrlounge.com / diffraction-aperture-and-starburst-effects / , which illustrates starburst effects related to photography. Thus, including random displacements in the dot pattern can provide a more comfortable experience for the user compared to a similar dot pattern where the scattering centers are evenly spaced. Alternatively or additionally, randomization of the dot pattern can reduce optical effects (such as diffraction or interference effects) exhibited in the reflected light, thereby reducing the perceptibility of the dot pattern to an observer.

[0121] In Figure 4C a random displacement is shown, which shows dots 401a - 401e positioned relative to an array lattice, where adjacent lattice nodes are spaced D from each other in the x - direction x , and D from each other in the y - direction y . As shown, D x = D y , however, more generally, the vertical and horizontal lattice spacings can be different.

[0122] For each dot, δx = A x ·D x ·RN[0,1] and δy = A y ·D y ·RN[0,1], where A x and A y are the dither amplitudes between 0 and 1 in the x - and y - directions, respectively, which can be the same or different. RN[0,1] is a random number between 0 and 1.

[0123] The dot size can also vary randomly, which can reduce optical effects associated with an array of dots of uniform size, such as glare. For example, as Figure 4C shown, the radial dimension of each dot can be different from the nominal dot radius r0. As shown, dot 401d has a nominal dot radius r0, while dots 401b and 401e have radii r b and r e and r b ≠r e . The dot radius can be set according to the formula r i = r0 + Δr, where Δr = A r ·r0·RN[0,1], where i represents the i-th dot, and A r is the dot radius jitter amplitude, which is set to a value between 0 and 1.

[0124] More generally, although the above example relates to the dot radius of nominal circular dots, jitter can be applied to other dot size parameters depending on the application. For example, jitter can be applied to the dot volume or other dot dimensions (e.g., the x-dimension, the y-dimension).

[0125] In some embodiments, the dot pattern can include both random jitter in dot position and random jitter in dot size.

[0126] In Figures 5A - 5F an exemplary dot pattern characterized by a transition region is shown. Figure 5A 、 5C and the patterns in 5E are characterized by dots evenly spaced in the scattering region. Figure 5B 、 5D and the patterns in 5F are characterized by dots randomly shifted from uniform spacing. The units of the horizontal and vertical axes are both mm. Figures 5A - 5F Each of

[0127]

[0128] In some embodiments, the dot pattern is characterized by a gradient in, for example, dot size and / or spacing. The dot pattern can be characterized by a gradient in the scattering efficiency of the dots (e.g., due to a gradient in the refractive index mismatch and / or shape of each dot). A graded dot pattern can reduce the conspicuousness of the pattern. For example, a gradual transition from the transparent part to the scattering part of the lens may not be as conspicuous as a sharp transition.

[0129] Referring to Figure 6A and 6B , exemplary graded dot patterns are shown.

[0130] Specifically, Figure 6AShows a graded dot pattern 600 with different spacings between adjacent dots. The light transmission aperture 610 transitions to a low-density region 620. In region 620, the distance between adjacent dots is relatively large, so dots with a low density are presented in region 620. Then, the low-density region 620 transitions to a high-density region 530, where the spacing between adjacent dots is small, so dots with a high density are presented. Then, the high-density region 630 transitions to a low-density region 640, in which the spacing between adjacent dots increases again. As a result, due to the graded transition from the light transmission aperture 610 to the outer edge of the lens, the graded dot pattern may be less conspicuous compared to a transition to a higher density, uniform dot pattern.

[0131] The dot density can be controlled not only by the spacing between adjacent dots, but also by the dot size. Refer to Figure 6B , for example, the dot pattern 650 is characterized in that the dots closer to the light transmission aperture 660 are smaller in size compared to the dots closer to the edge 680 of the dot pattern.

[0132] In another example, the lens can have a graded dot pattern that has both a varying dot size and a varying dot-to-dot distance.

[0133] The shape and / or composition of the dots can also vary radially, resulting in a graded pattern. For bulk scattering centers, for example, compared to the scattering centers at the center of the dot pattern, by forming scattering centers with a lower refractive index mismatch compared to the lens block material closer to the edge of the dot pattern, a graded pattern can be provided.

[0134] In some embodiments, information can be encoded into the dot pattern. For example, changes in the spacing, size, and / or shape of the dot pattern can be introduced according to a key, such that the information can subsequently be read by a person with that key. In some cases, information about the wearer can be encoded as a dot pattern, such as their identity and information about their vision.

[0135] In some embodiments, the dots can be dots of varying size. Refer to Figure 7A , the lens 700 includes a light transmission aperture 702 and a dot pattern including dots of different sizes: small dots 704 and large dots 706. In one embodiment, the small dots 704 are small relative to the large dots 706, and thus, the large dots 706 are large relative to the small dots 704.

[0136] In some embodiments, the small dots 704 and the large dots 706 can correspond to binary components. For example, the small dots 704 correspond to 0 and the large dots 706 correspond to 1 because the intensity of the reflected light departing from the small dots 704 and the large dots 706 will be different and can be interpreted as a binary code. When read in string form, the small dots 704 and the large dots 706 form a sequence of binary codes encoding information that includes, but is not limited to, the identity of the wearer or visual information. For example, the encoded information can include lens prescription information.

[0137] In some embodiments, in addition to the small dot size 704 and the large dot size 706, there can be other dot sizes. For example, the dot sizes of the dot pattern are not limited to two sizes. For example, when the sensor detects the reflected light of the encoded dot pattern from the lens 700, various dot sizes corresponding to different outputs can be used. The sensor can be configured to detect reflected light of three or more different intensities (e.g., the intensities of the reflected light from three or more different dot sizes of the dot pattern on the lens 700).

[0138] In some embodiments, the dots can be dots of an annular ring having a varying thickness. Refer to Figure 7B , the lens 720 includes a light transmission aperture 722 and a dot pattern including "annular rings" 724 (e.g., dots having an annular ring and a transparent center) and dots 726.

[0139] In some embodiments, the annular rings 724 and the dots 726 can correspond to binary components. For example, the annular rings 724 correspond to 0 and the dots 726 correspond to 1, and when read in string form, the annular rings 724 and the dots 726 form a sequence of binary codes encoding information that includes, but is not limited to, the identity of the wearer or visual information. For example, the encoded information can include lens prescription information.

[0140] In one embodiment, the size, shape, and / or thickness of the annular ring of the annular rings 724 vary, and thus, the intensity of the reflected light varies. The sensor can be configured to detect the varying intensity of the reflected light to convert it into an analog signal sent to the decoder. For example, certain shapes, sizes, and thicknesses of the annular rings of the annular rings 724 can correspond to predetermined encoded information. For example, an annular ring having a certain thickness can correspond to a predetermined lens prescription strength, and as the thickness of the annular ring increases, the prescription strength of the lens also increases.

[0141] In some embodiments, the dots can be shaped as symbols, such as alphanumeric symbols or logos. Refer to Figure 7C , the lens 740 includes a light transmission aperture 742 and a dot pattern of symbols 744.

[0142] In some embodiments, symbol 744 can be a logo, the same symbol, various symbols, simple shapes, complex shapes, alphanumeric digits, letters, and / or words. For example, symbol 744 can be a number indicating the prescription strength. In another example, symbol 744 can be the manufacturer's logo to indicate where to order replacement lenses. In another example, symbol 744 can be a shape indicating the diagnosis of a particular wearer (e.g., an ellipse with changes in meridian length and height corresponding to the myopia and astigmatism levels of the wearer).

[0143] Generally, changes in dot pitch, size, and / or shape are invisible to unaided human vision, and magnifying optics and / or machine reading systems are used to read out the encoded information. In some embodiments, a microscope reader is used to read out the encoded information. For example, a microscope or a similar magnifying optical system is used to enable an optometrist or a lens technician to read the encoded information from the lens.

[0144] In some embodiments, a machine reading system is used to read out the encoded information. Referring to Figure 8 , machine reading system 800 includes a lens 801 having a light - passing aperture 802 surrounded by a dot pattern 803, a light emitter 812, light 814, reflected light 816, a sensor 818, a database 820, a decoder circuit 822, and a controller 824.

[0145] In some embodiments, system 800 includes a light emitter 812. For example, light emitter 812 irradiates light 814, such as an LED or a laser, onto dot pattern 803. Dot pattern 803 is the encoded pattern as shown in Figures 7A - 7C .

[0146] Light 814 is (or is not) reflected away from dot pattern 803 in the form of reflected light 816. The intensity of reflected light 816 changes (e.g., ranging from no reflection to 100% reflection), as the presence or absence of certain dots can cause total reflection or non - reflection of light 814. Reflected light 816 can also be partial reflection of light 814. Similarly, in some embodiments, transmitted light or a combination of transmitted light and reflected light can be used to read out the encoded information

[0147] In some embodiments, system 800 includes a sensor 818. For example, sensor 818 is a light detector, such as a phototube. Various embodiments of sensor 818 can include, but are not limited to, laser scanners and camera - based readers. Sensor 818 detects and measures the intensity of reflected light 816 and outputs a signal. For example, the signal output by sensor 818 is an analog signal representing the intensity of reflected light 816. The signal corresponding to the intensity of reflected light 816 generated by sensor 818 is output to decoder circuit 822. For example, the intensity of reflected light 816 can be converted into a signal such as a switching pulse.

[0148] In some embodiments, the signal generated by sensor 818 is sent to database 820. For example, database 820 can cross-reference symbols (i.e., perform an image recognition search of the symbol, e.g., from Figure 7C to decode the signal. Database 820 can contain a library of symbols, images, alphanumerics, etc. For example, if dot pattern 803 includes a complex shape such as a logo or symbol, the sensor can send a signal related to the complex shape to database 820 for cross-referencing.

[0149] In one embodiment, decoder circuit 822 decodes the signal from sensor 818 and converts it into a digital signal. The digital signal is a digital representation of the signal from sensor 818, such as a binary code, where 0 represents an off pulse and 1 represents an on pulse.

[0150] Decoder circuit 822 sends the digital signal to controller 824. The digital signal can be read by controller 824. For example, decoder circuit 822 can send a binary code that controller 824 converts to text, and thus, the encoded information on dot pattern 803 can be read.

[0151] Although the above embodiments are characterized by examples where the regions of reduced contrast are annular (e.g., concentric circles around the light-transmitting aperture), more generally, other shapes are possible. For example, an elongated (e.g., oval) shape is possible. Generally, the regions of reduced contrast can cover the entire lens outside the light-transmitting aperture, or only a portion, leaving a clear lens at the lens periphery.

[0152] Generally, dots can be formed by the lens in a variety of ways. For example, dots can be formed using inkjet technology, such as those techniques disclosed in PCT / US2017 / 044635, titled "Ophthalmic Lens for the Treatment of Myopia," filed on July 31, 2017, the entire content of which is incorporated herein by reference.

[0153] In some embodiments, points are formed on the lens by exposing the lens to laser radiation. The laser radiation interacts locally with the lens material to create the points. Generally, as discussed in the following examples, lasers can be used to form points on the lens surface or in the bulk material of the lens. For example, exposing the lens surface to a laser beam having sufficient energy can create points by leaving small depressions and / or roughened spots on the surface. By selectively exposing regions of the lens surface to laser radiation, a point pattern can be formed on the surface. For example, when the laser beam is pulsed, the laser beam can be moved relative to the surface. The relative movement between the beam and the lens surface can be caused by moving the beam while keeping the surface fixed, moving the surface while keeping the beam fixed, or moving both the beam and the surface.

[0154] Generally, the optical properties of the points formed on the lens surface using a laser can be affected in a variety of ways. For example, the energy density of the laser beam pulses will generally affect the physical and / or chemical interaction of the laser with the lens material. For example, for certain pulse energies, the lens material can be melted at the places where it is exposed to form points. At some pulse energies, points can be formed by foaming the lens material. This can occur at higher energies relative to melting the lens. For some pulse energies, the interaction between the laser and the lens material can cause the lens material to change color (e.g., by carbonization). In other cases, lens material can be removed from the lens surface by ablation.

[0155] Other laser parameters can also affect the nature of the points formed using a laser. These parameters include laser wavelength, exposure time (e.g., the exposure time at each point location), and number of passes (e.g., multiple exposures of an area, with other areas exposed in between each exposure), and each of these can be selected to achieve the desired surface modification. Additionally, the interaction between the laser and the lens material will depend on the lens material itself. For example, lower pulse energies or fewer pulses can be used to form points in a lens material with a relatively low glass transition temperature compared to forming points in a lens material with a relatively high glass transition temperature.

[0156] In some embodiments, the laser and its operating parameters are selected to provide points having a specific range of forward scattering angles (e.g., between 3 degrees and 30 degrees). In particular, the laser parameters can be selected to achieve surface modification that results in a forward scattering angle of 15.5 to 19.5 degrees. In certain cases, the laser parameters are selected to achieve a scattering efficiency (e.g., haze) of 10 - 50%. In particular, the laser parameters can be selected to achieve a scattering efficiency of 15% to 19% and 38% to 42%.

[0157] The resolution of the laser beam at the lens surface can be less than the desired spot size. For example, the beam resolution (e.g., as determined by the FWHM of the intensity distribution) can be about 50% or less of the size of the spot (e.g., about 25% or less, about 10% or less, about 5% or less, about 1% or less). In some embodiments, the beam is capable of forming features that are 100 μm or less in size (e.g., 50 μm or less, 20 μm or less, 10 μm or less, 5 μm or less).

[0158] Reference Figure 9 , a laser system 900 for forming dots on the surface of a lens includes a laser 920, a beam chopper 930, focusing optics 940, a mirror 950, and a gantry 970. The laser 920 directs a laser beam towards the mirror 950, which deflects the beam towards the lens 901, and the lens 901 is positioned relative to the mirror 950 by the gantry 970. An actuator 960 (e.g., a piezoelectric actuator) is attached to the mirror 950. The gantry includes a lens mounting surface 980 that supports the lens 901. The laser system 900 also includes a controller (e.g., a computer controller) that communicates with the laser 920, the beam chopper 930, and the actuator 960.

[0159] The beam chopper 930 and the focusing optics 940 are positioned in the beam path. The chopper 930 periodically blocks the beam such that the lens 901 is exposed to discrete laser pulses. The focusing optics 940, which typically includes one or more optical elements (e.g., one or more lenses), focuses the beam onto a small enough spot on the surface of the lens 901 such that the area ablated on the lens surface by the beam corresponds to the desired spot size. The actuator 960 changes the orientation of the mirror 950 relative to the beam to scan the pulsed beam to different target points on the lens surface. The controller 910 coordinates the operation of the laser 920, the chopper 930, and the actuator 960 such that the laser system forms a predetermined dot pattern on the lens.

[0160] In some embodiments, the gantry 970 also includes an actuator. The gantry actuator can be a multi-axis actuator, e.g., moving the lens in two transverse dimensions orthogonal to the beam propagation direction. Alternatively or additionally, the actuator can move the gantry along the beam direction. Moving the gantry along the beam direction can be used to keep the exposed portion of the lens surface at the focal position of the beam, regardless of the curvature of the lens surface, thereby maintaining a substantially constant spot size across the lens surface. The gantry actuator can also be controlled by the controller 910, which coordinates this gantry movement with the other elements of the system. In some embodiments, the gantry actuator is used instead of the mirror actuator.

[0161] Typically, the laser 920 can be any type of laser capable of generating light with sufficient energy to ablate the lens material. Gas lasers, chemical lasers, dye lasers, solid-state lasers, and semiconductor lasers can be used. In some embodiments, an infrared laser can be used, such as a CO2 laser (having an emission wavelength of 9.4 μm or 10.6 μm). Commercially available laser systems can be used, such as (for example) a CO2 laser system manufactured by Universal Laser Systems, Inc. (Scottsdale, Arizona) (e.g., the 60W VLS4.60 system). In some embodiments, a femtosecond laser can be used. For example, a commercial femtosecond laser system can be used, such as a femtosecond laser system manufactured by Trumpf (Santa Clara, California) (e.g., the TruMicro 2030 laser device as part of the TruLaser Station 5005), to form a dot pattern of a desired shape and size. Compared to the maximum energy of a single pulse, the burst mode of such a laser device can achieve a much higher burst energy, resulting in a higher ablation rate. This exemplary laser system can provide a pulse duration of less than 400 femtoseconds and a maximum pulse energy of 50 μJ.

[0162] The pulse duration and pulse energy are typically selected to provide dots of a desired size. For example, in some embodiments, the laser 920 forms a predetermined dot pattern on the lens 901 by melting the surface of the lens 901 (e.g., laser etching). For example, the laser 920 heats and melts a portion of the surface of the lens 901 to form a dot because laser etching causes the melted material of the lens 901 to expand, such that a recessed pit and a raised well around it are formed, thereby forming a dot.

[0163] In certain embodiments, the laser 920 forms a predetermined dot pattern on the lens 901 using laser foaming. For example, when the laser interacts with the lens material, the material softens or melts, and bubbles are formed in the softened / melted material. These bubbles are trapped when the material cools and returns to its room temperature state. The trapped bubbles can effectively scatter light, thereby providing dots.

[0164] In an embodiment, the laser 920 forms a predetermined dot pattern on the lens 901 using laser marking. For example, laser marking forms a predetermined dot pattern on the lens 901 by causing a color change on the lens 901, for example, due to a chemical or physical change in a portion of the lens 901 that forms the predetermined dot pattern. In another embodiment, the laser 920 forms a predetermined dot pattern on the lens 901 by carbonizing the lens 901 using laser marking.

[0165] In some embodiments, the laser 920 is used to ablate a predetermined dot pattern on the lens 901. For example, the laser 920 is used to ablate (e.g., remove material) the lens 901 by locally evaporating or sublimating the material of the lens 901 to form a predetermined dot pattern. After ablation, pits are formed on the lens 901.

[0166] In some embodiments, to reduce the conspicuity of the dot pattern (e.g., reduce backscattering and reflection due to ablation pits at the scattering centers), the surface of the ablation pits on the lens 901 is modified to reduce surface roughness. Reducing surface roughness can reduce the effect of small-angle light scattering (e.g., for scattering angles less than 3 degrees). For example, the surface of the ablation pits on the lens 901 can be modified by a second pass to melt the rough surface of the ablation pits (e.g., by using a lower energy beam). The lower energy beam can be achieved, for example, by defocusing the laser 920 (e.g., by increasing the beam width of the laser 920). In some embodiments, continuously reducing the conspicuity of the dot pattern involves defocusing the laser 920 in multiple iterations. For example, the laser 920 is defocused with increasing defocus (e.g., increasing the beam width with each pass) in several passes (e.g., every second, third, fourth, etc. pass) to affect the taper of the pits (e.g., feathering or smoothing the pit edges). In some embodiments, reducing the conspicuity of the dot pattern includes performing multiple overlapping ablations to form an ablation pit having multiple overlapping ablation pits (e.g., two or more overlapping concentric circles).

[0167] In some embodiments, reducing the conspicuity of the dot pattern includes coating an anti-reflection layer on the back surface of the lens 920. In some embodiments, a reflective layer is coated on the front surface of the lens. This is particularly beneficial if laser ablation is performed on the back surface of the lens 901. Generally, the laser 920 has a greater effect on the coating compared to the material of the lens 901, thereby affecting the taper of the pits (e.g., feathering or smoothing the pit edges).

[0168] In some embodiments, a focusing optical device with a small depth of focus can be used in combination with the curvature of the lens surface to provide variable dot sizes across the lens surface. For example, refer to Figure 10, and similar to system 900, a laser system 1000 for forming dots on the surface of a lens 1001 includes a laser 1020, a beam chopper 1030 (or other modulator for generating laser pulses), focusing optics 1040, a mirror 1050, and a gantry 1080. The laser 1020 directs a laser beam 1025 towards the mirror 1050, which deflects the beam 1025 towards the lens 1001, and the lens 1001 is positioned relative to the mirror 1050 by the gantry 1080. An actuator 1060 is attached to the mirror 1050. The laser system 1000 also includes a controller 1010 that communicates with the laser 1020, the beam chopper 1030, and the actuator 1060.

[0169] The beam chopper 1030 and the focusing optics 1040 are positioned in the beam path. The chopper 1030 periodically blocks the beam 1025 such that the lens 1001 is exposed to discrete laser pulses. The focusing optics 1040 focus the beam 1025 onto a small enough spot 1045 on or near the surface of the lens 1001 such that the area ablated on the lens surface by the beam 1025 corresponds to the desired dot size. The actuator 1060 changes the orientation of the mirror 1050 relative to the beam 1025 to scan the pulsed beam 1025 to different target points on the lens surface. The controller 1010 coordinates the operation of the laser 1020, the chopper 1030, and the actuator 1060 such that the laser system 1000 forms a predetermined dot pattern on the lens 1001.

[0170] As Figure 10 indicated by the arrow in, moving the gantry 1080 laterally moves the lens 1001 parallel to the focal plane 1035 of the laser beam 1025. Due to the curvature of the lens surface, the lens surface will not always coincide with the focal plane 1035 at the focal spot 1045 of the laser beam, which means that the intensity of the laser radiation on the lens surface will vary according to the lateral position of the lens relative to the spot 1045. Generally, the amount of etching on the lens surface will depend on the intensity of the laser radiation it receives. Therefore, positions on the lens surface exposed to the defocused beam are etched less strongly than those where the lens surface coincides with the focal plane 1035. Assuming that the laser pulse time and the lateral translation speed are constant, the result is that at positions where the lens surface coincides with the focal plane 1035, the etching rate will be the highest, and the further the lens is translated from this position, the etching rate will decrease. Thus, a graded pattern can be obtained simply based on the curvature of the lens surface.

[0171] Of course, other exposure parameters (e.g., pulse time, pulse energy, dot composition, such as the position of forming dots through multiple overlapping or nearby ablation centers, foaming or melting regions) can be used in conjunction with or separately from the lens curvature to obtain the desired graded dot pattern.

[0172] The laser system can also be used to form scattering centers in the bulk material of the lens. In many cases, the effect of laser radiation on the bulk properties of an optical material (such as plastic or glass) depends on the intensity of the laser radiation. These changes can occur through one or more different mechanisms, such as photochemical changes, photothermal changes (e.g., light-induced heating that alters the properties of the material), and / or some other mechanism. Generally, the greater the intensity, the greater the change in the optical material. In many cases, this change is not necessarily a linear relationship. For example, there may be a certain threshold intensity below which, even if any changes occur in the bulk material, they are minimal. At a certain threshold intensity, changes begin to occur. For example, referring to Figure 11A , a graph showing this non-linear relationship between the refractive index change of the lens material and the laser intensity is shown.

[0173] Laser radiation with a relatively low intensity I0 only produces a small change ΔR0 in the refractive index; however, when the laser intensity reaches 2I0, a significant change ΔR0 in the refractive index occurs.

[0174] This non-linear behavior of the refractive index change can be used to locate the scattering centers embedded in the lens material. For example, the lens can be exposed to two or more laser beams, each with a beam intensity less than the threshold intensity required to cause a significant refractive index change. Although each laser beam is too weak to produce an obvious refractive index change, the region where the laser beams overlap (e.g., all laser beams can be focused on the same point) will experience sufficient refractive index change, which corresponds to the creation of scattering centers. Alternatively, if the beam focus is within the bulk material, an optical device with a narrow focal region can be used.

[0175] For example, referring to Figure 11B , a laser system 1105 is shown. The laser system 1105 uses two overlapping beams to create embedded scattering centers in the lens 1101. The laser system 1105 includes two lasers 1120A and 1120B, beam choppers 1130A and 1130B, focusing optics 1140A and 1140B, mirrors 1150A and 1150B, actuators 1160A and 1160B, and a gantry 1180. A controller 1110 is connected to each of the actuators, focusing optics, and lasers. Each laser operates in a manner similar to that described in Figure 10 . The focusing optics and mirrors are configured to focus the beams 1185A and 1185B onto a common region 1190 inside the lens 1101, where the intensity of the overlapping beams is sufficient to affect the change in the lens material sufficient to form scattering centers. Outside the overlapping region, the intensity rapidly drops to a value below any threshold for significant refractive index change.

[0176] More than two lasers can be used. Alternatively or additionally, the beam from a single laser can be split and separately directed to the lenses such that they overlap at the target area, thereby creating scattering centers.

[0177] Other arrangements are possible. For example, multiple laser beams can enter the lens from the same surface rather than from opposite surfaces as Figure 11B shown.

[0178] Although the foregoing description relates to ophthalmic lenses for glasses, the disclosed principles can be applied to other forms of ophthalmic lenses, such as contact lenses. In some embodiments, dot patterns can be provided on the contact lens to provide a similar therapeutic effect. The size and spacing of the dots in the dot pattern of the contact lens can be adjusted to subtend a comparable solid angle in the user's field of view to the dot pattern described above for the spectacle lenses.

[0179] Examples

[0180] Using a Trumpf Trumark 5000 marking laser station equipped with a nanosecond UV laser with a pulse repetition rate of 20 kHz, dots were formed on Trivex lenses. The laser station was operated at a scanning speed of 1,000 mm / s and 100% output power. The diameter of these dots was approximately 170 microns, and depending on the dot spacing, a haze of 15% to 42% was produced. In some cases, the dots were formed by marking two concentric overlapping circles with radii of approximately 0.06 mm and 0.03 mm, consisting of individual laser marks with a diameter of approximately 0.04 mm, thereby producing dots with a total diameter of 0.17 mm. The spacing between adjacent dots was 0.24 mm or 0.365 mm.

[0181] Other embodiments

[0182] Multiple embodiments have been described. Other embodiments are in the following claims.

Claims

1. An ophthalmic lens, comprising: a lens material having two opposing curved surfaces; and A scattering region that surrounds the light-transmitting aperture, wherein the scattering region has a plurality of spaced-apart scattering centers, the size and shape of the scattering centers being such as to scatter incident light, the scattering centers being arranged in a pattern such that each scattering center is located at or near a corresponding array point of a two-dimensional array, in which array the spacing between array points is a first distance D in a first direction of the plane of the array x , and a second distance D in a second direction of the plane of the array y , the second direction being orthogonal to the first direction wherein the center of each scattering center is displaced by an amount δx in the first direction and by an amount δy in the second direction relative to the corresponding array point, where δx = A x ·D x ·RN[0,1], and δy = A y ·D y ·RN[0,1], where A x and A y are respectively fixed dither amplitudes between 0 and 1 in the first direction and the second direction, A x and A y are the same or different, and RN is a random number between 0 and 1.

2. The ophthalmic lens according to claim 1, wherein the spacing between the array points ranges from 0.2 mm to 1 mm.

3. The ophthalmic lens according to claim 1, wherein, The maximum size of the scattering centers in the plane of the array ranges from 0.08 mm to 0.5 mm.

4. The ophthalmic lens according to claim 1, wherein, The arrangement of the scattering centers includes a displacement of each scattering center relative to the corresponding array point.

5. The ophthalmic lens according to claim 1, wherein, At least some of the scattering centers have a size that varies relative to other scattering centers in the plane of the array.

6. The ophthalmic lens according to claim 5, wherein, The variation in the size of at least some of the scattering centers in the plane of the array is 0.5 times or less of the nominal value.

7. The ophthalmic lens according to claim 1, wherein, At least some of the scattering centers have a volume that varies relative to other scattering centers in the volume of the scattering centers.

8. The ophthalmic lens according to claim 7, wherein, The variation in the volume of at least some of the scattering centers is 0.5 times or less of the nominal value.

9. The ophthalmic lens according to claim 1, further comprising a lens axis, wherein the light transmission aperture and the scattering region are substantially centered on the lens axis.

10. The ophthalmic lens according to claim 1, wherein, The scattering region includes a first scattering region and a second scattering region, the second scattering region being arranged between the light transmission aperture and the first scattering region, the second scattering region including scattering centers, the size and arrangement of the scattering centers being such that they scatter incident light less strongly than the scattering centers of the first scattering region.

11. The ophthalmic lens according to claim 1, wherein, The pattern includes an irregular variation in the size of the scattering centers.

12. The ophthalmic lens according to claim 1, wherein, At least one of the spacing and size of at least some of the scattering centers is changed to encode information into the scattering centers.

13. The ophthalmic lens according to claim 1, wherein, In the plane of the array, the shape of the scattering centers is substantially circular.

14. The ophthalmic lens according to claim 1, wherein, At least some of the scattering centers are shaped as at least one of a logo and an alphanumeric symbol.

15. The ophthalmic lens according to claim 1, wherein, The ophthalmic lens is one of a plano lens, a single vision lens, or a multifocal lens.

16. The ophthalmic lens according to claim 1, wherein, The ophthalmic lens is one of an eyeglass lens and a contact lens.

17. The ophthalmic lens according to claim 1, wherein, The scattering region is an annular region.

18. The ophthalmic lens according to claim 1, wherein, The light transmission aperture is a circular aperture.

19. A pair of glasses, comprising: a frame; and one or more ophthalmic lenses mounted in the frame, each ophthalmic lens comprising: a lens material having two opposing curved surfaces; and A scattering region that surrounds the light-transmitting aperture, wherein the scattering region has a plurality of spaced-apart scattering centers, the size and shape of the scattering centers being such as to scatter incident light, the scattering centers being arranged in a pattern such that each scattering center is located at or near a corresponding array point of a two-dimensional array, in which array the spacing between array points is a first distance D in a first direction in the plane of the array x , and a second distance D in a second direction in the plane of the array y , the second direction being orthogonal to the first direction wherein the center of each scattering center is displaced by an amount δx in the first direction and by an amount δy in the second direction relative to the corresponding array point, where δx = A x ·D x ·RN[0,1], and δy = A y ·D y ·RN[0,1], where A x and A y are respectively fixed dither amplitudes between 0 and 1 in the first direction and the second direction, A x and A y are the same or different, and RN is a random number between 0 and 1.

20. The glasses according to claim 19, wherein, the size and arrangement of the scattering centers are such that the image contrast of an object viewed through the scattering region is reduced by at least 30% compared to the image contrast of the object viewed through the light transmission aperture.

21. The pair of glasses according to claim 19, wherein, the one or more ophthalmic lenses have a refractive power that corrects the wearer's vision to 20 / 20 or better through the light transmission aperture; and for at least a portion of the wearer's peripheral vision through the scattering region, the lens corrects the wearer's vision to 20 / 25 or better.

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