Subsurface modified intraocular lens for high definition and extended depth of focus

Abstract

An intraocular lens configured to provide an extended depth of focus. The lens includes a virtual aperture including a first sub-surface region having a first refractive index and a plurality of modified sub-surface locations. The modified sub-surface locations have a second refractive index different from the first refractive index. The locations can be configured to diffract light to distribute the light broadly across the retina.

Description

[Technical field]

[0001] (CROSS REFERENCE TO RELATED APPLICATIONS) This application claims priority to U.S. patent application Ser. No. 63 / 257,405, filed on October 19, 2021, entitled "HIGH DEFINITION AND EXTENDED DEPTH OF FIELD VIA SUBSURFACE MODIFICATION OF INTRAOCULAR LENS," the contents of which are incorporated by reference in their entirety herein. [Background technology]

[0002] The human eye often suffers from aberrations, such as defocus and astigmatism, which must be corrected to provide acceptable visual acuity in order to maintain a high quality of life. The correction of these defocus and astigmatism aberrations can be achieved with lenses. Lenses can be placed, for example, on the spectacle surface, on the corneal surface (contact lenses or corneal implants), or even within the eye, either as a phakic (phakic: lens intact) or aphakic (aphakic: lens removed) intraocular lens (IOL).

[0003] In addition to basic aberrations such as defocus and astigmatism, the eye often has higher-order aberrations such as spherical aberration and other aberrations. The eye also has chromatic aberrations (which are generally caused by the change in focus depending on the wavelength of visible light). These higher-order and chromatic aberrations have a negative impact on the quality of a person's vision. The negative impact of higher-order and chromatic aberrations is greater the larger the pupil. Vision that eliminates these aberrations is sometimes called high definition (HD) vision.

[0004] Presbyopia is a condition in which the eye loses the ability to focus on objects at different distances. Aphakic eyes are presbyopic. A standard monofocal IOL implanted in an aphakic eye restores vision at a single focal distance. Various devices and techniques are used to obtain improved vision at various distances, including the use of a monofocal IOL in combination with bifocal or progressive-addition spectacles. Monovision IOL systems are another option for restoring near and distance vision -- one eye is set at a different focal distance than the fellow eye, providing binocular summation of the two foci to provide a blended view. Monovision is the most common method of correcting presbyopia today, where an IOL is used to correct the dominant eye for distance vision and the nondominant eye for near vision to achieve glasses-free binocular vision from far to near.

[0005] IOLs may also be multifocal, for example bifocal (having two focal regions - usually distance and near) or trifocal (having three focal regions - usually distance, intermediate, and near). Many multifocal IOLs are designed with one or more focal regions distributed in the addition range. However, the use of elements with discrete foci is not the only possible design strategy. The use of extended depth of field (EDOF) elements, i.e. elements that generate continuous focal segments over the required addition (or addition range), can also be considered. These methods are not fully acceptable because stray light from the various focal regions reduces the person's vision. Summary of the Invention

[0006] Systems, devices and methods are disclosed that overcome the limitations of IOLs by providing at least a phakic or aphakic IOL that simultaneously provides correction of defocus and astigmatism, reduces higher order and chromatic aberrations, and provides extended depth of focus to improve quality of vision. Additionally, the central optic of the IOL provides a small "add" sector to improve quality of vision corresponding to objects in the "near vision" region.

[0007] The disclosed IOL has an optical configuration in which central focused light reaches a central focal region of the retina and disperses defocused and aberrated light broadly across the retina's periphery. High power refraction and / or total internal reflection are employed in one or more regions of the IOL that scatter the defocused and aberrated light broadly across the retina. The result is an optical configuration that can increase depth of focus and reduce monochromatic and chromatic aberrations to provide high definition vision across a wide range of objects from far to near vision.

[0008] In one aspect, an intraocular lens configured to provide an extended depth of focus is disclosed, the intraocular lens having: an optical zone including at least one anterior optical surface and at least one posterior optical surface; a first peripheral region peripherally located relative to the optical zone, the first peripheral region including a virtual aperture, the virtual aperture including an anterior virtual aperture surface and a posterior virtual aperture surface, the virtual aperture including a first subsurface region having a first refractive index, the virtual aperture further including a plurality of modified subsurface locations. and a second peripheral region located peripherally relative to the first peripheral region, the second peripheral region comprising haptics for positioning the intraocular lens within an eye, the haptics including an outermost region of the intraocular lens; wherein when the intraocular lens is implanted in an eye, a first plurality of light rays incident on the anterior optical surface pass through the optical zone to form an image on a retina, and a second plurality of light rays incident on the anterior virtual aperture surface are widely dispersed in a downstream direction from the intraocular lens toward the retina and across the retina, whereby the image comprises an extended depth of focus, and further, the virtual aperture reduces monochromatic and chromatic aberrations of the image.

[0009] The details of one or more variations of the subject matter described herein are set forth in the accompanying drawings and the description below. Other features and advantages of the subject matter described herein will become apparent from the description and drawings, and from the claims. [Brief description of the drawings]

[0010] [Figure 1A] FIG. 1A illustrates a basic method of utilizing the pupil size of the myopic eye to reduce monochromatic aberrations and increase or extend the depth of focus. [Figure 1B] FIG. 1B illustrates a basic method of utilizing the pupil size of the myopic eye to reduce monochromatic aberrations and increase or extend the depth of focus. [Figure 2A] FIG. 2A shows a basic method of using the pupil size of a hyperopic eye to reduce monochromatic aberrations and increase depth of focus. [Figure 2B] FIG. 2B illustrates a basic method of using the pupil size of a hyperopic eye to reduce monochromatic aberrations and increase depth of focus. [Figure 3A] FIG. 3A shows a basic method of using the pupil size of the emmetropic eye to reduce monochromatic aberrations and increase depth of focus. [Figure 3B] FIG. 3B illustrates a basic method of using the pupil size of the emmetropic eye to reduce monochromatic aberrations and increase depth of focus. [Figure 4A] FIG. 4A shows a basic method for using pupil size to reduce chromatic aberration. [Figure 4B] FIG. 4B shows a basic method for using pupil size to reduce chromatic aberration. [Figure 5A] FIG. 5A illustrates the basic concept of a virtual aperture for limiting the effective pupil size. [Figure 5B] FIG. 5B illustrates the basic concept of a virtual aperture for limiting the effective pupil size. [Figure 6A] FIG. 6A illustrates the overall structure of an exemplary IOL. [Figure 6B] FIG. 6B illustrates the overall structure of an exemplary IOL. [Figure 6C]FIG. 6C illustrates the overall structure of an exemplary IOL. [Figure 6D] FIG. 6D illustrates another embodiment of an exemplary IOL. [Figure 7] FIG. 7 shows an exemplary IOL with sampled hexagonal microlenses within the virtual aperture zone. [Figure 8] FIG. 8 shows an exemplary hexagonal geometry for the microlenses. [Figure 9] FIG. 9 shows the center portion of a two-dimensional array of microlenses. [Figure 10A] FIG. 10A shows two adjacent hexagons, adjacent corresponding microlens spheres, and a smooth surface profile supporting minimal curvature. [Figure 10B] FIG. 10B shows two adjacent hexagons, adjacent corresponding microlens spheres, and a smooth surface profile supporting minimal curvature. [Figure 11] FIG. 11 illustrates an exemplary division of the optical zone of an IOL to provide near and far vision partitions. [Figure 12] FIG. 12 relates to a system for modifying the sub-surface region of an IOL. [Figure 13] FIG. 13 relates to a system for modifying the sub-surface region of an IOL. [Figure 14] FIG. 14 relates to a system for modifying the sub-surface region of an IOL. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] [Detailed Description] Before further describing the subject matter, it is to be understood that the subject matter described herein is not limited to the particular embodiments described, and may, of course, vary. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only, and is not intended to be limiting. All technical terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this subject matter belongs, unless otherwise defined.

[0012] Systems, devices, and methods are disclosed that overcome the limitations of IOLs by at least providing a phakic or aphakic IOL that provides correction of defocus and astigmatism, reduces higher order monochromatic and chromatic aberrations, and provides extended depth of focus to improve quality of vision. The disclosed IOLs may be referred to herein as Z+ optics or Z+ IOLs. PCT application PCT / US20 / 37014 describes related systems and methods and is incorporated herein by reference in its entirety.

[0013] An explanation of the basic principles used to reduce monochromatic and chromatic aberrations and provide increased depth of focus is provided. Figure 1A shows a schematic of a single converging lens 1 centered on an optical axis 2. An incident ray 3 from a distant object is parallel to the optical axis and intersects with the focal point 4 of the lens (subscripted b, c, d, e, or f based on the corresponding figure). If the lens power is properly selected, the focal point will coincide with the observation plane 5, otherwise there will be a mismatch between the lens power and the position of the observation plane and the focal point will be in front of or behind the observation plane.

[0014] In FIG. 1A, the focal position is in front of the observation plane. If all the incident rays at the same ray height as the incident ray 3 are traced, a blur circle 6 is formed on the observation plane 5. The observation plane is perpendicular to the optical axis, so it is shown as a vertical line in the figure. For the sake of visualization, the blur circles 6 and 8 are shown in the plane of the drawing, but in reality, the blur circle is included in the observation plane. Other incident rays with a ray height lower than the incident ray 3 fall inside this blur circle 6. One such ray is the incident ray 7, which is closer to the optical axis than the incident ray 3. The incident ray 7 also intersects the focal point 4 and then the observation plane 5. If all the incident rays are traced at the same ray height as the incident ray 7, a blur circle 8 smaller than the blur circle 6 is traced.

[0015] FIG. 1B shows the same optical system as FIG. 1A, but now the incident rays are for an object close to the optical system, as indicated by the inclination of the incident rays 3b and 7b. The focal point 4 for the close object (with subscripts a, b, c, d or f, based on the corresponding figure) is closer to the observation plane, with the effect that both blurring circles 6b and 8b are smaller than their counterparts in FIG. 1A, but the principle remains the same: rays intersecting the lens 1 near the optical axis have less blurring on the observation plane. Relating this simple optical structure of FIG. 1 to the human eye, the converging lens 1 represents the principal plane of the optical system of the eye, including the cornea and the crystalline lens or intraocular lens. The observation plane 5 represents the retina. As depicted, the focal point 4 is in front of the observation plane (retina), so this illustration is for a myopic or nearsighted eye. The size of the blur circle 6, 8 (or 6b, 8b) represents the amount of defocus on the retina, with a smaller blur circle diameter providing a sharper view than a larger blur circle diameter.

[0016] It should be noted that a similar relationship between the height of the incident ray and the size of the blur circle also holds for a presbyopic or hyperopic eye. This is illustrated diagrammatically in Figures 2A and 2B, which show rays corresponding to a hyperopic eye. The lower the ray height, the smaller the blur circle at the retina (viewing surface) in Figure 2A for rays 3, 7 from a distant object, and in Figure 2B for rays 3b, 7b.

[0017] Similarly, Figures 3A and 3B (collectively referred to as Figure 3) show that the characteristics of the height of parallel rays and the diameter of the blur circle are the same for an emmetropic eye. For distant objects, the focal point 4e is on the retina (because the eye is emmetropic), and the radius of the blur circles 6e and 8e is zero. For close objects, the focal point 4f is behind the retina, and the blur circle 8f corresponding to the ray 7b closer to the optical axis has a smaller diameter than the blur circle 6f corresponding to the ray 3b further from the optical axis.

[0018] In general, the eye has aberrations, which means that the focal point in the eye changes as the position of the incoming light beam changes. But regardless of where the focal point is (in front of the retina, on the retina, or behind the retina), the lower the height of the incoming light beam, the smaller the diameter of the blur circle on the retina. In other words, for a given amount of ocular defocus (dioptric error), a lower height of the incoming light beam improves vision. This principle is used when we squint our eyes, blocking incoming light beams away from the eye's optical axis with our eyelids in an attempt to see unfocused distant or nearby objects more clearly.

[0019] The ray traces shown in Figures 1A-3B are for a single wavelength of incident light. For polychromatic light, there are multiple wavelengths. This is generally illustrated by three rays of different wavelengths as shown in Figures 4A and 4B (collectively referred to as Figure 4). It is well known that the refractive index of the eye components and typical optical materials decreases with increasing wavelength of light.

[0020] In FIG. 4A, a converging lens 21 has an optical axis 22. An incident colored light beam 23 consists of three wavelengths of light: blue (450 nm), green (550 nm), and red (650 nm), which span the visible light range. Due to the different refractive indices of the three wavelengths, the blue light beam 24 is refracted more than the green light beam 25, which is refracted more than the red light beam 26. If the green light beam is in focus, it will intersect the viewing surface 27 at the optical axis. The color spread of these three light beams creates a colored blur circle 28 on the viewing surface.

[0021] In FIG. 4B, the chromatic incident rays 29 have a lower ray height than the chromatic rays 23 in FIG. 4A. This results in less chromatic blur 33 at the viewing plane. Thus, similar to the monochromatic blur of FIGS. 1A-3B, the lower height of the chromatic rays results in less chromatic blur. The situation in FIG. 4 can be related to the eye by considering the converging lens 21 as the eye's principal plane and the viewing plane 27 as the retina. Since the human eye typically has a large chromatic aberration (approximately 1.0-1.2 diopters over the central visual range), reducing the chromatic aberration can be significant resulting in a noticeable improvement in the quality of the eye's vision, especially as measured by its contrast sensitivity.

[0022] Taken together, Figures 1A-4B show that lowering the beam height reduces both monochromatic and chromatic aberrations at the retina, and therefore improves the quality of vision. This can be achieved by reducing the pupil diameter to block rays that are far from the axis, or by spreading the light from those rays more uniformly and / or more widely across the retina, so that less of the many aberrant rays contribute to the central retinal blur circle. Another feature of this effect is the increased depth of focus as the beam height is lowered, as shown in Figures 1B, 2B, and 3B.

[0023] FIG. 5A shows a converging lens 34 with an optical axis 2 and an aperture 35. A parallel incident ray 36 passes just through the aperture and then through the lens focal point 37, intersecting with the observation plane 38. All parallel rays at the same height as ray 36 trace a small blur circle 39 on the observation plane. A parallel incident ray 40 is blocked by the aperture and cannot proceed to the observation plane and produce a large blur circle 41. Thus, the aperture, which reduces the height of the incident ray, reduces the diameter of the blur at the observation plane.

[0024] FIG. 5B shows a "virtual aperture" - that is, an aperture that does not actually block light rays, but the optical effect on central vision is similar. In this figure, a bundle of light rays 40b entering the virtual aperture propagates through the virtual aperture 42 and is further refracted, diffracted, scattered, reflected, and / or diffused, so that the resulting light rays 43 are widely spread out and contribute very little to the stray light (blurring light) at any one point on the viewing surface. This is the main mechanism of operation of the disclosed IOL.

[0025] One type of light altering mechanism in a virtual aperture is a number of holes of a predetermined size arranged in the area or throughout the virtual aperture. The holes are individually or collectively configured to allow light to pass through to produce a diffraction effect or to achieve or change a desired opacity. The holes have a spatial arrangement / pattern, diameter, depth, and / or density of the hole pattern that allows a particular light scattering pattern on the retina to achieve a desired diffusion effect, such as uniform light distribution and / or light scattering. In one embodiment, the holes have a density throughout the virtual aperture to achieve between 10 percent and 100 percent light transmission in the virtual aperture, and the holes are arranged to achieve this.

[0026] [Example optical layout of an intraocular lens] 6A-6C show exemplary IOL layouts employing optical principles to achieve the benefits of reduced monochromatic and chromatic aberrations and increased depth of focus. FIG. 6A shows a front view of the IOL, which may be a front view. FIG. 6B shows a rear view of the IOL, which may be a posterior view. FIG. 6C shows a side view of the IOL. The IOL includes a central optical zone 46 (having a back surface 46b) that provides other corrections required for the lens, such as defocus, astigmatism, and spherical aberration. In general, IOLs employing virtual apertures have a smaller central optical zone diameter compared to conventional IOLs. This results in a smaller central thickness, which in turn facilitates implantation of the IOL and allows for smaller corneal incisions during surgery, e.g., about 2.2 mm incision.

[0027] The IOL includes a virtual aperture 48 located further outwardly with respect to the central location of the central optical zone 46. Moving outwardly from the virtual aperture 48, at least one IOL haptic 50 (having a back surface 50b) is located on the IOL. The haptic 50 can be formed of one or more arms extending outwardly from the periphery, defining the peripheral most edge of the IOL. In a non-limiting example, the diameter of the optical zone is 1.5 mm. A 1.5 mm diameter optical zone has been shown to be at or near the minimum threshold required to admit sufficient light to the eye under mesonic conditions (or intermediate viewing conditions). In another non-limiting example, the diameter of the optical zone is sized from 1.5 mm to 2.8 mm or 3 mm. In another embodiment, the size of the optical zone is 1.5 mm to 3.3 mm, which corresponds to the diameter. As another non-limiting example, the diameter of the optical zone is 1.65 mm or 3.3 mm. The haptic 50 can define the outermost peripheral region of the IOL. When the IOL is placed in the eye, a first plurality of light rays incident on the anterior optical surface of the optical zone can pass through the optical zone to form an image on the retina, while a second plurality of light rays incident on the anterior surface of the virtual aperture are directed from the IOL toward the retina and are widely dispersed in a downstream direction across the retina, such that the image includes an extended depth of focus, and further, the virtual aperture reduces monochromatic and chromatic aberrations of the image. The optical zone can include at least one of a bifocal optical system, a trifocal optical system, and a multifocal optical system.

[0028] The virtual aperture is connected to the optical zone 46 by a first transition region 47 located at the periphery of the optical zone 46, and the virtual aperture becomes a first peripheral region surrounding or partially surrounding the optical zone. The haptics can include a second peripheral region for positioning the intraocular lens in the eye. The first transition region is located outside the periphery of the optical zone 46. The second transition region 49 connects the haptics 50 to the virtual aperture 48. The first transition region 47 and the second transition region 49 are configured to ensure zero-order and first-order continuity of the outer surface of the IOL on either side of the respective transition regions. A common way to achieve this is a polynomial function, such as a cubic Bezier function. Transition methods such as these are known to those skilled in the art. A common way to achieve these transition regions is a polynomial function, such as a cubic Bezier function. Transition methods such as these are known to those skilled in the art. At the back side of the IOL is a central optical zone 46b, haptics 50b, and a transition 47b between them. 6A-6C are not necessarily to scale, and the haptic shapes are for illustrative purposes only. Other haptic shapes and sizes known to those of skill in the art may be suitable as well. The first and second transition regions do not necessarily have to be present in the IOL.

[0029] The IOL has an anterior surface and a posterior surface, and each of the components of the IOL, including the optic zone 46, the first transition region 47, the second transition region 49, the virtual aperture 48, and the haptics 50, can have respective anterior and posterior surfaces. The optic zone 46 has an anterior optical surface that can include at least one multifocal zone and / or a toric region. At least a portion or region of the anterior and / or posterior surface, such as the region of the virtual aperture or other portions of the IOL, can have a surface contour or shape that can achieve a desired or predetermined effect on the light passing therethrough. In a non-limiting example, the surface contour of the anterior and / or posterior surface includes a region with a ripple-type contour, such as a wave shape, an undulating shape that forms a series of raised and lowered surfaces. The surface contour can achieve various effects on the light passing through the IOL. For example, the surface contour can cause the spread of stray light to be wider or wider depending on the type of surface contour used. The surface contour can be used to achieve a spreading of stray light that is directed away from the retinal focal point.

[0030] 6D shows a front view of another embodiment of an IOL that includes a central optic zone, a plurality of peripheral haptics 605, and at least one zone having a surface contour such as a ripple or wave, as described further below. In one example, the optic zone has a diameter of 1.5 mm and functions as a lens to sharply focus distant objects onto the central retina.

[0031] The IOL includes one or more orientation structures 610, such as one or more protrusions or nubs. In the illustrated embodiment, the orientation structures 610 are disposed on a portion of the periphery of the IOL, with at least one orientation structure 610 disposed on a first side of the vertical meridian of the IOL and a second orientation structure 610 disposed on a second side of the vertical meridian. meridian The vertical meridian is shown in dashed line in Figure 6D. The orientation structure 610 is configured to allow a clinician, such as a surgeon, to easily detect that the correct side of the IOL is facing the front of the eye. Note that if the IOL is oriented with its back surface facing the front of the eye, the orientation structure 610 will be counterclockwise relative to the vertical of the lens.

[0032] As explained, the haptics 605 provide the mechanical interface with the eye and hold each zone of the IOL in the proper position relative to the eye.

[0033] [Detailed example of optical zone - hexagonal microlens virtual aperture] 7 shows a front view of an IOL including a virtual aperture having one or more hexagonal structures. The IOL has a central optical zone 709, a first transition zone 710, a hexagonal microlens virtual aperture 711, a second transition zone 712, and haptics 713. The first transition zone 710 connects the central optical zone 709 to the hexagonal microlens virtual aperture 711, and the second transition zone 712 connects the hexagonal microlens virtual aperture 711 to the haptics 713.

[0034] The virtual aperture employs microlenses in a two-dimensional hexagonal sampling array that mimics the photosensor sampling of the retina, a layout that is beneficial for spreading light widely across the retina when the IOL is implanted in the eye.

[0035] The hexagonal microlens virtual aperture 711 includes a plurality of hexagonal shaped microstructures disposed on the front and / or back surface of the IOL. The hexagonal shape refers to the outer boundary of each hexagonal micro-structure, which has an outer boundary defined by the hexagonal micro-structure when viewed from the front or back side of the IOL. That is, the hexagonal micro-structure can have an outer boundary defined by a hexagon. Inside the boundary of each hexagonal micro-structure, a small lens is disposed. The lens can be a structure disposed on or within the microstructure. The lens may be monolithically formed as part of the microstructure during manufacturing. To help prevent unwanted light patterns on the retina, the centers of the micro-lenses inside each hexagon are randomly moved or positioned on the IOL, and the radius of the micro-lenses is also adjusted. To facilitate the fabrication of hexagonal microlens virtual apertures, a blending region or fillet is placed between the hexagonal boundaries of the microlens having a radius of curvature larger than the radius of the lathe cutter that forms the microlens, which radius is, in a non-limiting example, about 0.05 mm.

[0036] The hexagons can have a variety of dimensions. In one embodiment, the hexagons of the microstructure are taller than they are wide. In another embodiment, the hexagons of the microstructure are wider than they are tall. In another embodiment, the outer boundary of the microstructure is a polygon of any shape.

[0037] With further reference to FIG. 7, a first transition zone 710 is configured to provide a smooth structural blend between the edge of the optic zone 709 and the central hexagonal microlens region 711. A second transition zone 712 is responsible for providing a smooth structural blend between the peripheral hexagonal microlens region 711 and the haptics 713. These transition zones can be effectively achieved using Bezier curves or portions of Bezier surfaces to define the surfaces of the respective zones. Other transition functions may be suitable as well and are known to those skilled in the art. It should be understood that any of the embodiments of the IOLs described herein may be configured to not include a transition zone.

[0038] The microlenses are implemented as one or more surfaces at least partially defined by a spherical, conical, or other similar surface capable of achieving high optical power to spread incident light rays widely across the retina. For example, the microlenses are implemented as one or more surfaces at least partially defined by a prism or pyramidal shape. As an example, the following discussion illustrates an embodiment with spherical microlenses.

[0039] [Nominal hexagonal sampling] An exemplary hexagon is shown in FIG. 8 illustrating an exemplary microstructure of a virtual aperture with the microstructure defined by a hexagon 1014. In FIG. 8, the hexagon 1014 is shown within a circumscribing circle 1015 that defines the shape or size of the hexagon. The hexagon has a width 1016 and a height 1017. As shown, the height of the hexagon is equal to the diameter of the circumscribing circle 1015. With respect to the radius of the circumscribing circle, the width of the hexagon is found using the Pythagorean theorem given by Equation (1) below, and the height is given by Equation (2):

[0040]

number

[0041] Also, (a) each interior angle of the hexagon is 120 degrees, (b) each side and the center point form an equilateral triangle with an interior angle of 60 degrees, and (c) the length of the sides of the hexagon is equal to the radius of the circumscribing circle.

[0042] The center portion of a hexagonal 2D array (or 2D array) is shown in Figure 9. The dimensions of the hexagonal 2D array are defined by equation (3).

[0043]

number

[0044] In this formula, N is a positive even integer, for example 50. The center position (x, y) of each hexagon is given by formulas (4a) and (4b).

[0045]

number

[0046]

number

[0047] The indices of the two-dimensional hexagonal array elements (or hexagonal array elements) and the hexagon center coordinates (x, y) are shown as pairs of numbers above and below each hexagon center in FIG.

[0048] [Smooth profile across the entire microlens] FIG. 10A shows two exemplary adjacent hexagons at the center of a two-dimensional array. The center of the array may coincide with the optical axis of the IOL. Hexagon 1018 has its center at the center of the optical axis of the IOL. Microlens sphere 1020 has its center located at a random (x,y) distance from the center of hexagon 1018. Hexagon 1019 is directly adjacent to hexagon 1018, and microlens sphere 1021 has its center located at a random (x,y) distance from the center of hexagon 1019. The radius of microlens sphere 1020 is larger than the radius of microlens sphere 1021. In FIG. 10A, coordinates are referred to as (x,y), where z is out of the page (or up on the page), x is to the right, and y is up. This therefore represents a view looking down onto the surface of the lens, with each microlens sphere being convex, thus creating a local positive high power surface. Figure 10A also shows the profile AA', which extends through the centers of microlens spheres 1020 and 1021.

[0049] FIG. 10B shows a side view of the shape shown in FIG. 10A. Spheres 1020 and 1021 are shown corresponding to the same spheres in FIG. 10A. The centers of the spheres are shown as points 1022 and 1023, which correspond to spheres 1020 and 1021, respectively. The coordinates in this view are referred to as (x, z), with y pointing inward (or downward) to the page, x pointing to the right, and z pointing upward. Here, profile AA′ is seen to be the curve on the surface of the microlens array (or microlens array) due to spheres 1020 and 1021 and spherical fillet 1024. The spheres shown in FIG. 10B are convex and the fillet sphere is concave. In another example, the microlens sphere is concave and the fillet sphere is convex. This latter sphere orientation offers the advantage of being able to use a smaller fillet sphere radius that is not limited by the radius of the cutting tool.

[0050] According to the manufacturing process of the IOL, the radius of the spherical fillet is selected to be larger than the radius of the lathe cutting tool so that the surface can be generated with a given cutting tool. To find the surface points of the smooth profile AA', the center 1025 of the spherical fillet 1024 is defined as a known radius. For simplicity, the center of the microlens is constrained to have a z value on a plane perpendicular to the optical axis. Point P shown in FIG. 10B has the same (x, y) coordinates as the center 1025 of the fillet sphere 1024 and is located on the line connecting the microlens centers 1022 and 1023. The coordinates of point P are given by equation (5a).

[0051]

number

[0052] where

[0053]

number

[0054] In these formulas:

[0055]

number

[0056]

number

[0057] TIFF2024536565000010.tif1279

[0058] The set of center points of the fillet sphere centers relative to the entire microlens sphere can be determined from equation (6a).

[0059]

number

[0060] where

[0061]

number

[0062] The angle θ lies in a plane containing P and is perpendicular to a line intersecting the centers of the two microlens spheres. Using this geometry, surface points can be traced along the curved segments AB, BB', and B'A'. These points form a continuous blending between each microlens in the virtual aperture, which can be cut on a lathe using a tool with a radius smaller than the radius of the fillet spheres.

[0063] To define the surface of an IOL using the above concepts, the following is performed: First, the central optics of the IOL is identified, for example, as described in PCT Patent Application No. PCT / US20 / 37014 and U.S. Patent Application No. 16 / 380,622, the contents of which are incorporated herein by reference in their entirety. The diameter of the optic zone may be approximately 1.5 mm, in non-limiting examples, and may be between (1.4 mm and 1.6 mm). The optical powers of the optic zone range from -10D to 40D, varying in 0.25D or 0.5D increments. The cylinder powers for a toric IOL (or astigmatic IOL) range from 0.5D to 6.0D, varying in 0.25D to 0.5D increments.

[0064] A virtual aperture for the microlens array is then generated using the concepts above, where the radius of the circle enclosing the hexagon is approximately 0.125 mm. The centers of the individual microlens spheres are randomly varied in x and y by 0.05 mm. The radius of the microlens spheres is randomly varied in 0.05 mm increments from an average radius of approximately 0.2 mm. The width of the virtual aperture area is approximately 2.0 mm.

[0065] The radius of the fillet sphere of the microlens array is set to be about 25% larger than the radius of the lathe tool, which may be about 0.05 mm.

[0066] The width of the front transition regions is set to about 0.15 mm each, and the width of the back transition regions is set to about 2.3 mm.

[0067] The haptic configuration is constructed according to routine procedures within the skill of those skilled in the art.

[0068] Once the anterior and posterior surfaces have been designated, individual profile samples are taken from the center to the periphery of the IOL to designate points for the lathe cutting tool (or lathe cutting file).

[0069] [Multi-area optical zone] FIG. 11 illustrates a schematic of a multi-region, e.g., two-region, optical zone 1101 that may be included in any of the IOLs described herein. The regions are labeled 1109 and 1110. These represent two separate regions within the optical zone for two separate powers. For example, a first separate (discrete) region is the central region 1109, which typically provides distance vision. A second separate (discrete) region is the peripheral region 1110, which typically provides near vision. The "add" of the near vision region is approximately 3.0D, with a range of 2.0-35D.

[0070] Due to the nature of the optical mechanism of IOLs, providing a bifocal (or two-focal) optical zone is not as problematic as a regular-sized optical zone of 5.0 mm or more, because the extra aberrations caused by incoming rays outside the typical 1.5 mm central optical zone diameter are distributed widely across the retina and do not adversely affect the central vision of the eye.

[0071] [Optical Zone Area Distribution] In an exemplary configuration, the distance power area of ​​the central optic occupies 75% of the optical zone area and the near power area of ​​the central optic occupies 25% of the optical zone area. The central optical zone is typically 1.5 mm in diameter, so the central region 1109 of the optical zone is 1.3 mm in diameter, with the remainder of the optical zone providing 25% for the near vision area 1110.

[0072] In some eyes, it may be preferable to allocate the area of ​​the far and near vision zones 50% each, or 25% for far vision and 75% for near vision. Providing one eye with the majority of the optical zone area for far vision (e.g., 75%-100%) and the other eye with more optical zone area for near vision may be used in extended depth of focus / monovision patients. In this case, both eyes have extended depth of focus, but one eye (usually the dominant eye) has slightly better performance for far vision and the other eye has slightly better visual performance for near vision.

[0073] [Optical surface in optical zone area] Either a conic refractive profile or a diffractive profile can be used to provide the desired optical power in the optic zone region.

[0074] For a simple conic refractive profile, each optical zone provides its optical power (or refractive power) through a conic section, whereby the apex radius of curvature provides the desired optical power, and the conic constant (K) value is set to reduce spherical aberration in that region. Optimization to find the apex radius of curvature and the conic constant can be done numerically using a commercially available optical design program such as Zemax, or using closed-form analytical equations. Both of these methods are known to those skilled in the art. Additionally, the conic constant value can be adjusted to further improve the depth of focus performance of the IOL. Conic constant values ​​in the range of -7.5 to -9.5, typically -8.717, provide such improvement over an equivalent biconvex conic optical zone.

[0075] When a simple conic refractive profile is used, with the central region 9 of the optical zone providing distance vision and the peripheral region 10 providing near vision, there is negligible transition between the regions, This is the preferred arrangement since the transition region generally introduces stray light that would otherwise be properly focused by one of the two optical power regions.

[0076] When a simple conic refractive profile is used, with a central region 9 of the optical zone providing near vision and a peripheral region 10 providing distance vision, a transition between the regions is necessary to smoothly join the regions. This transition profile is typically implemented by either a Bezier curve or a circular fillet, both of which are known to those skilled in the art.

[0077] [Peripheral add zone] In another embodiment, the summing zone can be located in the virtual aperture region. In yet another embodiment, the summing zone can be located on the posterior side in the large transition region. A peripheral summing zone can exist along with a central optic summing zone.

[0078] [Cylinder power for astigmatism correction] To correct astigmatism, a cylinder component can be added to one or both sides of the IOL's optic zone. Cylinder powers for this purpose range from 0.5 to 6.0 diopters, varying in increments of 0.25 or 0.5 D.

[0079] To define the surface of an IOL using the concepts described above, the following is done: First, the central optic of the IOL is identified as described above. The diameter of the optic zone is approximately 1.5 mm, for example between (1.4 mm and 1.6 mm). The optical power (or refractive power) of this optic zone ranges from -10D to 40D, varying in 0.25D or 0.5D increments. The cylinder power (or cylindrical power) for a toric IOL (or astigmatic IOL) ranges from 0.5D to 6.0D, varying in 0.25D to 0.5D increments.

[0080] A virtual aperture is then generated using the concepts described in the previous disclosure. The width of the virtual aperture area is approximately 2.0 mm.

[0081] The width of the front transition regions is set to about 0.15 mm each, and the width of the back transition regions is set to about 2.3 mm.

[0082] The design of haptics is considered a separate problem and is a routine procedure for those skilled in the art.

[0083] Once the anterior and posterior surfaces have been designated, individual profile samples are taken from the center to the periphery of the IOL to designate points for the lathe cutting tool (or lathe file).

[0084] [Subsurface correction of IOL] In one embodiment, at least one region of the IOL, e.g., the virtual aperture 48 of the IOL, includes at least one subsurface modification, including at least a portion of the IOL's internal structure. The IOL may include such subsurface modifications as well as, optionally, features of the anterior and / or posterior outer surfaces of the IOL, such as shape changes or contours on the outer surfaces. The subsurface modifications are configured to achieve a desired optical effect, such as diffusing, homogenizing, or redirecting light, for light passing through or otherwise interacting with the subsurface modifications. The IOL subsurface modifications provide an alternative, efficient, and reproducible mechanism for diffusing and / or homogenizing light passing through at least one region of the IOL. As described below, the degree of light diffusion and / or homogenization can be tailored to specific requirements by varying the size of the laser damage spot or the modified refractive index loci. To achieve a degree of light diffusion, the spacing or density of the placement of the damage spots or loci, or the number of layers of those damage spots or loci, can be varied. The configuration (or placement) of the damage spots or loci can also be used to achieve control over the direction of light, for example, to direct the light in a desired direction. This allows fine-tuning or customizing the optical properties of the IOL or light diffusion device. The intraocular lens can be part of a system that includes a laser delivery device configured to deliver a laser to the material based on which the IOL is formed.

[0085] In any embodiment, the particular loci may intersect the anterior or posterior surface (e.g., located tangent to the respective surface), and these loci may be located at any depth relative to the anterior or posterior surface, including at the surface itself.

[0086] The apparatus (or device) can achieve diffraction of light in a variety of ways, for example, through diffractive features contained within or coupled to the apparatus, such as an IOL. The diffractive features are designed to be small enough in size to impart and produce a diffractive effect on light rays that interact with the diffractive features, dispersing the light widely on the retina (or other object). Examples of diffractive features include subsurface modifications, prisms (or portions thereof, e.g., edges, points, vertices), step shapes, holes or openings in the IOL, and / or masks disposed on the IOL. The apparatus can also be configured to achieve diffraction of light through diffractive features disposed on the apparatus (or on a surface of the apparatus) or on the top side of the apparatus.

[0087] In one embodiment, the subsurface modifications are not located in a virtual aperture, but rather are part of the IOL's optical correction zone, which may or may not be in the area of ​​the IOL's virtual aperture 48. In another embodiment, the subsurface modifications form a light diffusing region of an IOL, or form a light diffusing region of an optically transparent body or structure that is not an IOL. For example, the features described herein can be used in light diffusing devices that are not IOLs.

[0088] In a first exemplary embodiment of the subsurface modification, a laser is configured to interact with an interior region (i.e., a subsurface region or location) of the IOL to achieve a subsurface modification, such as modifying a structure of the IOL at a subsurface (subsurface) location. The same laser or a different laser can also interact with a surface region of the IOL, with a first laser interacting with the surface region and a second laser or a different laser interacting with the subsurface region. The subsurface region is located at least between the anterior and posterior surfaces of the IOL. For example, a laser is focused on the subsurface (subsurface) of the IOL to heat the material of the IOL and form a damage region or damage spot at the subsurface location within the material of the IOL.

[0089] 12 shows a schematic diagram of a laser system 1205 designed to interact with an IOL 1210 (or a portion or body of material that is later formed within, disposed on, or incorporated into the IOL 1210, or a material that forms a non-IOL device, e.g., a light diffusing device). The laser system 1205 is designed to emit a laser 1220 that interacts with the IOL, e.g., the laser 1220 is focused or otherwise emits a predetermined amount of energy at a specific location on a sub-surface of the IOL 1210.

[0090] The laser system 1205 is designed to focus the laser 1220 on the subsurface of the IOL material (e.g., glass or polymeric material, as non-limiting examples) or emit a predetermined level of energy at a subsurface location. In one embodiment, the laser is rapidly pulsed. The laser 1220 creates one or more microscopic damage spots in the interior of the IOL material (i.e., below the outer surface of the IOL material or between the anterior and posterior surfaces). In an exemplary embodiment, the pulsed laser causes rapid heating and expansion of the material near the focused laser spot, which creates stress and small-scale fractures in the material, gas expansion, thereby creating the damage spots. The resulting spallation or damage spots can be of very small dimensions (e.g., on the order of tens of microns).

[0091] The laser can be moved rapidly and precisely in the lateral X / Y directions while remaining focused at a specific depth (Z direction) within the material relative to the front or rear exterior surface. A pattern or array of damage spots can be created at this depth. It is also possible to create two or more layers of damage spots. The depth of the laser focus is rapidly and precisely controlled with micron depth resolution.

[0092] In this manner, the laser forms a two-dimensional or three-dimensional array of damage spots that may be arranged in any of a wide variety of patterns. A two-dimensional array includes two or more damage spots arranged in the same plane. A three-dimensional array includes two or more two-dimensional arrays. FIG. 13 is a schematic diagram of a portion of an IOL 1210. In FIG. 13, for ease of illustration, a portion of the IOL 1210 is depicted as prismatic in shape, but it should be understood that the shape may vary and is not limited to a prismatic shape. A two-dimensional or three-dimensional array of damage spots 1305 is disposed completely below the outer surface of the IOL 1210. The array includes one or more damage spots. In the illustrated example, the damage spots form an equally spaced rectangular array, but the shape and spatial arrangement of the array, as well as the damage spots within the array, may vary.

[0093] In one example of an IOL manufacturing process, the following steps may be performed: First, an IOL is formed from a plastic (or other material) blank, such as on a lathe, using known processes for forming IOLs. The IOL is machined from a variety of materials with an optical zone in the central portion configured to allow for extended depth of focus or monocular focusing. In one embodiment, the IOL is configured to have the features described herein with reference to Figures 6A-7. Next, a virtual aperture may be formed with flat posterior and anterior surfaces (i.e., the outer surfaces are not machined or otherwise modified), or the anterior or posterior surfaces may be machined to include desired surface features, such as grooves, ridges, waves, ripples, prisms, or other surface features. Next, one or more haptics are machined into the substrate blank to specifications to allow for surgical implantation and proper placement within the eye.

[0094] A laser system 1205 is then used to create a two- or three-dimensional pattern of damage spots within the virtual aperture of the IOL, as described above. That is, the damage spots can be aligned in a common plane. In another embodiment, the IOL includes a series of planes arranged to form a three-dimensional array of planes, each plane including one or more damage spots.

[0095] A process or system can be used to properly align the IOL to properly and precisely target the laser damage. The two- or three-dimensional array of damage spots is configured to allow a predetermined or desired amount of light transmission and diffusion. For example, the pattern of damage spots can be a pattern of 5-10 layers of 50 micron spots spaced 50 microns apart and arranged in a rectangular or annular grid. The pattern can include an offset between layers so that gaps are filled when viewed axially. Because a uniform distribution of damage spots can result in visual artifacts when implanted in the eye, the exemplary spot pattern employs a pseudorandom placement strategy.

[0096] In a second exemplary embodiment of subsurface modification, a femtosecond pulsed laser (FSPL) is configured to interact with the IOL (e.g., focused at subsurface locations of the IOL) to modify the refractive index. The femtosecond pulsed laser creates modified loci at the subsurface locations, which have a different refractive index than the material prior to modification. Different patterns of modified loci may provide selected dioptic power, toric tuning, and / or aspheric tuning. The refractive index of the modified loci may also differ from the refractive index of the surrounding subsurface locations. The different refractive index may be caused by nonlinear absorption of photons resulting from exposure to focused laser light by the femtosecond pulsed laser.

[0097] Referring again to FIG. 12, the laser system 1205 can be configured to emit a femtosecond pulsed laser 1220. The femtosecond laser is focused to a point on the subsurface of the IOL 1210 and pulsed with a very specific time and intensity profile. The laser can be controlled in the XY plane, for example using a Galvo positioning controller, which allows for very fast and precise positioning of the beam in the XY plane. Furthermore, this system allows for very high frequency and very precise focusing control when coupled with or using an acoustically controlled focusing mechanism. This allows for extremely fast and precise positioning of the femtosecond laser's focused spot at any depth and at any XY coordinate within the substrate.

[0098] Femtosecond laser pulses impact the interior regions of the IOL, altering the refractive index of specific subsurface regions of the IOL to form specific loci. This process can be applied to various IOL materials, for example glass, hydrophobic and hydrophilic acrylics. The mechanism that results in the change in refractive index varies from substrate to substrate, but in all mentioned substrates, the area affected by the laser has a lower refractive index than the surrounding material. The decrease in refractive index may depend on various factors, such as the properties of the substrate, the intensity and time of laser irradiation, and the thickness of the material. Generally, a change in refractive index of about 0.06 is consistently achievable. For example, if the original hydrophilic acrylic substrate has a nominal refractive index of 1.459 in a fully hydrated state, the refractive index of the treated area after laser irradiation may be as low as 1.399.

[0099] 14 is a schematic diagram showing a portion of an IOL 1210. An array of modified refractive index loci 1405 (each having a modified refractive index) is disposed completely underneath the outer surface of the IOL 1210. The array includes one or more loci. In the illustrated example, the loci form an equally spaced rectangular array, although the shape and spatial arrangement of the array, as well as the loci within the array, may vary.

[0100] In the sample manufacturing process, an IOL is formed using a lathe to form an IOL with a virtual aperture as described herein. Referring to Figure 12, the IOL is aligned with a femtosecond laser device 1205, which emits a focused femtosecond laser 1210 at a sub-surface location to create a desired pattern of regions of modified refractive index to achieve the desired light diffusion, transmission and beam steering.

[0101] In either embodiment of subsurface modification, multiple layers (or multi-layering) of damage spots or loci within the array can diffuse and homogenize a thin beam of light as it enters the IOL.

[0102] To the extent that the IOL or a portion of the IOL diffuses light, that diffusion may be achieved by various features or techniques associated with the IOL or associated with the manufacture of the IOL. These techniques may include one or more surface modifications of the IOL, such as using an annular lathe to modify the surface of the IOL. Annular or non-annular surface modifications, including microlenses, may be used. These modifications may be randomly or pseudo-randomly placed on the IOL. In another embodiment, the surface of the IOL is polished (via sandblasting, polishing with specific abrasives, etc.) to randomly roughen the surface or to achieve a desired surface roughness. The surface may also be roughened by chemically etching it or by using a laser to selectively burn away surface material (or surface substances). A combination of the aforementioned techniques may also be used.

[0103] In another embodiment, diffusion is achieved by modifying the interior aspects of the IOL while leaving the exterior unmodified (or combined with modifications to the exterior surface of the IOL). The IOL can incorporate a holographic diffuser (or holographic diffuser plate) whose interference pattern is either sandwiched inside the IOL or formed directly during the IOL's manufacture, such as during polymer curing. The IOL can also, or alternatively, employ a milky material, such as a combination of two or more diffusive materials that are homogeneously translucent but not transparent. This can increase the attenuation and scattering of light. Sub-surface laser engraving can also be employed to achieve diffusion.

[0104] IOLs can be manufactured by a variety of processes and equipment, including lathing, injection molding, sandwich construction, ablative lasers, masked lasers, and the use of cured polymers. Subsurface laser marking, embossing, glass embossed plates, silicone molding, and surface casting can also be used. It is also possible to modify the surface of the IOL using chemical etching.

[0105] Although this specification contains many specifications, these should not be construed as limiting the scope of the invention as claimed or as it may be claimed, but rather as a description of features embodying a particular embodiment. Certain features described herein in the context of separate embodiments may also be implemented in combination in a single embodiment. Conversely, various features described in the context of a single embodiment may also be implemented in multiple embodiments separately or in any suitable subcombination. Furthermore, even if features are described above as acting in a particular combination and are originally claimed as such, one or more features of the claimed combination may be deleted from the combination in some cases, and the claimed combination may be directed to a subcombination or variation of the subcombination. Similarly, although operations are depicted in the figures in a particular order, this should not be understood as requiring such operations to be performed in the particular order or sequence shown, or to perform all of the operations shown, to achieve desired results. Only some examples and implementations have been disclosed. Variations, modifications and extensions to the described examples and implementations, as well as other implementations, may be made based on the disclosed content.

Claims

1. 1. An intraocular lens configured to provide an extended depth of focus, the intraocular lens comprising: an optical zone including at least one anterior optical surface and at least one posterior optical surface; a first peripheral region peripherally positioned relative to the optical zone, the first peripheral region including a virtual aperture, the virtual aperture including a front virtual aperture surface and a rear virtual aperture surface, the virtual aperture including a first sub-surface region having a first refractive index, the virtual aperture further including a plurality of modified sub-surface locations, the modified sub-surface locations having a second refractive index different from the first refractive index resulting from nonlinear absorption of photons due to illumination by focused laser light; and a second peripheral region located peripherally relative to the first peripheral region, the second peripheral region including a haptic for positioning the intraocular lens in the eye, the haptic including the outermost region of the intraocular lens; when the intraocular lens is implanted in an eye, a first plurality of light rays incident on the anterior optical surface pass through the optical zone and form an image on the retina; An intraocular lens, wherein a second plurality of light rays incident on the anterior virtual aperture surface are widely dispersed in a downstream direction from the intraocular lens toward the retina and across the retina, thereby causing the image to include an extended depth of focus, and further, the virtual aperture reduces monochromatic and chromatic aberrations in the image.

2. The intraocular lens of claim 1 , wherein the anterior or posterior surface of the virtual aperture comprises a hexagonal microstructure having an outer boundary defined by a hexagon.

3. The intraocular lens of claim 1 , wherein the anterior or posterior surface of the virtual aperture comprises a hexagonal microstructure having microlenses.

4. The intraocular lens of claim 3 , wherein at least one microlens comprises a convex sphere.

5. The intraocular lens of claim 3 , wherein at least one microlens comprises a concave sphere.

6. The intraocular lens of claim 3 , wherein at least one microlens comprises a conical surface.

7. The intraocular lens of claim 1 , wherein the first peripheral region is connected to the central optical zone by a first transition region.

8. 8. The intraocular lens of claim 7, wherein the second peripheral region is connected to the first peripheral region by a second transition region.

9. The intraocular lens of claim 1 , wherein the optical zone comprises at least two discrete regions including a first discrete region and a second discrete region.

10. The intraocular lens of claim 9, wherein the first individual region is a central region and the second individual region is a peripheral region located around the central region.

11. 10. The intraocular lens of claim 9, wherein the first discrete region includes a first distance power and the second discrete region includes a second distance power.

12. The intraocular lens of claim 1, wherein the first peripheral region includes a plurality of holes of a predetermined size, the plurality of holes being collectively configured to allow light to pass therethrough to produce a diffraction effect.

13. 10. The intraocular lens of claim 1, wherein the size of the optical system is between 1.5 mm and 3.3 mm.

14. The intraocular lens of claim 1 , wherein at least one sub-surface location is configured to allow light to pass therethrough to produce a diffraction effect.

15. The intraocular lens of claim 1 , wherein the plurality of modified subsurface locations are arranged in a two-dimensional array of locations.

16. The intraocular lens of claim 1 , wherein the plurality of modified subsurface locations are arranged in a three-dimensional array of locations.

17. 17. The intraocular lens of claim 16, wherein the sub-surface locations form a rectangular array of equally spaced locations.

18. The intraocular lens of claim 1 , wherein the second refractive index differs from the first refractive index by 0.06.

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