High definition and extended depth of field intraocular lens

Abstract

Systems, devices and methods to overcome IOL deficiencies are disclosed by providing at least one of a phakic or aphakic IOL to provide correction of defocus and astigmatism, reduce higher order monochromatic and chromatic aberrations and provide extended depth of field to improve visual quality. The IOL includes a virtual aperture integrated into the IOL. The structure and design allow light rays that intersect the virtual aperture and are widely dispersed across the retina, effectively preventing the light rays from reaching a detectable level on the retina. The virtual aperture helps to eliminate monochromatic and chromatic aberrations, resulting in a high-definition retinal image. The depth of field is increased on larger diameter optic zone IOLs for a given definition of acceptable vision.

Description

[0001] Priority Statement

[0002] This application claims priority to U.S. Patent Application No. 62 / 861,120, filed June 13, 2019, entitled "High-Resolution and Extended Depth-of-Field Intraocular Lens," U.S. Patent Application No. 62 / 986,115, filed March 6, 2020, entitled "High-Resolution and Extended Depth-of-Field Intraocular Lens," and U.S. Patent Application No. 62 / 988,802, filed March 12, 2020, entitled "Microprism Region for Extending Depth of Focus of Intraocular Lens." The contents of the aforementioned referenced applications are hereby incorporated in their entirety into this document. Background Technology

[0003] The human eye frequently suffers from aberrations such as defocus and astigmatism, which must be corrected to provide acceptable vision for maintaining a high quality of life. These aberrations can be corrected using lenses. The lens can be located, for example, at the spectacle plane, the corneal plane (contact lenses or corneal implants), or within the eye as a phakic (fully lenticulum) or aphakic (removed lens) intraocular lens (IOL).

[0004] In addition to the basic aberrations of defocus and astigmatism, the human eye also frequently experiences higher-order aberrations such as spherical aberration. Chromatic aberration, usually caused by variations in wavelength within the visible spectrum, also exists in the eye. These higher-order aberrations and chromatic aberrations negatively impact visual quality. The negative effects of higher-order aberrations and chromatic aberrations increase with pupil size. Vision free from these aberrations is often referred to as high-definition (HD) vision.

[0005] Presbyopia is the loss of the eye's ability to focus on objects at different distances. Aphakic eyes are susceptible to presbyopia. Implanting a standard monofocal intraocular lens (IOL) into an aphakic eye restores vision at a single focal length. Various devices and procedures are used to provide improved vision at a range of distances, including the use of a monofocal IOL combined with bifocal or progressive supplemental lenses. A monocular IOL system is another option for restoring near and far vision—one eye has a different focal length setting than the other, thus providing a binocular sum of two focal points and providing mixed vision. Monoopia is currently the most common method for presbyopia correction, using an IOL to correct the dominant farsighted eye and the non-dominant nearsighted eye, aiming to achieve binocular vision from far to near without glasses.

[0006] Furthermore, IOLs can be multifocal, such as bifocal (with two focal areas—typically far and near) or trifocal (with three focal areas—far, intermediate, and near). Most multifocal IOLs are designed to distribute one or more focal areas within an additional range. However, using elements with a set of discrete focal points is not the only possible design strategy: elements with extended depth of field (EDOF), i.e., elements that produce a continuous focal length across the desired addition, can also be considered. These approaches are not entirely acceptable because stray light from the individual focal areas can reduce visual acuity. Summary of the Invention

[0007] This invention discloses systems, apparatus, and methods for overcoming IOL defects, which at least by providing a phakic or aphakic IOL to correct defocus and astigmatism, reduce higher-order monochromaticity and chromatic aberration, and provide extended depth of field to improve visual quality. The IOL includes a virtual aperture integrated into it. This structure and design allow light rays to intersect with and be widely dispersed across the retina, effectively preventing light from reaching detectable levels on the retina. The virtual aperture helps eliminate monochromaticity and chromatic aberration, producing a high-resolution retinal image. For a given definition of acceptable visual acuity, the depth of field increases over a larger diameter optical zone (IOL).

[0008] On one hand, the present invention discloses an intraocular lens for providing extended depth of field, the intraocular lens comprising: an optical region including at least one anterior optical surface and at least one posterior optical surface; a first peripheral region located peripherally relative to the optical region, the first peripheral region including a virtual aperture including an anterior virtual aperture surface and a posterior virtual aperture surface; and a second peripheral region positioned peripherally relative to the first peripheral region, the second peripheral region including a tactile element for positioning the intraocular lens within the eye, wherein the tactile element includes the outermost region of the intraocular lens; wherein, when the intraocular lens is implanted... When inserted into the eye, a first multiple beam of light incident on the anterior optical surface passes through an optical region to form an image on the retina; and at least one of: (a) a first surface profile on the anterior surface of the intraocular lens, the first surface profile including at least one annular region; (b) a second surface profile on the posterior surface of the intraocular lens, the second surface profile including at least one annular region; wherein the second multiple beam of light incident on the anterior virtual aperture surface is widely dispersed from downstream of the intraocular lens toward and through the retina, such that the image includes an extended depth of field, and further wherein the virtual aperture reduces aberrations in monochrome and color images.

[0009] In related methods, such as any embodiment of the IOL described herein, the IOL is implanted or otherwise coupled to the eye, such as the human eye. The IOL is used to modify or adjust the transmission of light to the retina of the eye according to the features described herein.

[0010] Details of one or more variations of the subject matter described herein are set forth in the accompanying drawings and the following description. Other features and advantages of the subject matter described herein will be apparent from the description and drawings, as well as from the claims. Attached Figure Description

[0011] Figure 1A and 1B This demonstrates a basic method for using the pupil size of a nearsighted eye to reduce monochromatic aberration and increase or expand depth of field.

[0012] Figure 2A and 2B The illustration shows a basic method for using the pupil size of a farsighted eye to reduce monochromatic aberration and increase depth of field.

[0013] Figure 3A and 3B This demonstrates a basic method for using the pupil size of an emmetropic eye to reduce monochromatic aberration and increase depth of field.

[0014] Figure 4A and 4B The illustration shows a basic method for reducing chromatic aberration using pupil size.

[0015] Figure 5A and 5B The basic concept of virtual aperture that limits the effective pupil size is illustrated.

[0016] Figure 6A , 6B The diagram 6C illustrates the overall structure of the example IOL.

[0017] Figure 7 The diagram illustrates the variables used to calculate the principal optical power of the optical region.

[0018] Figure 8 The diagram illustrates the ray tracing process used to optimize the conic constant K for a given meridian.

[0019] Figure 9 The illustration shows specific points and distances along the meridian of an exemplary IOL profile.

[0020] Figure 10 The illustration shows the details of the virtual aperture distribution.

[0021] Figure 11A and 11B The results of cubic Bézier curves and minimizing curvature along the curves are shown.

[0022] Figure 12 An example embodiment showing the corrugated profile is provided, wherein a series of annular, concentric corrugations are formed on the surface of a virtual aperture.

[0023] Figure 13An example embodiment of a microprism shape on a virtual aperture surface is shown.

[0024] Figure 14 An example embodiment of a smooth surface with a virtual aperture is shown.

[0025] Figure 15 A table showing a variety of combinations of surface profiles between the front and rear surfaces of an IOL or between a portion of an IOL.

[0026] Figure 16 A side view outline of an IOL with a front corrugated virtual aperture and a rear microprism region is shown.

[0027] Figure 17 A close-up of the microprism-to-tactile transition area of ​​the IOL is shown.

[0028] Figure 18 An example geometry of the transition from microprism to tactile rounded corners is shown.

[0029] Figure 19 A close-up of the transition area from the microprism to the optical zone is shown.

[0030] Figure 20 The geometry of the transition fillet from the microprism to the optical zone is shown.

[0031] Figure 21 The refraction and total internal reflection of light at the rear surface of the microprism region are shown.

[0032] Figure 22 An example structure of the microprism region is shown.

[0033] Figure 23 The valley and peak rounded corners in the microprism region are shown.

[0034] Figure 24 An example configuration of the first valley fillet and the first peak fillet is shown.

[0035] Figure 25 The diffusion of stray light in the front surface of the corrugated virtual aperture and the smooth back surface IOL is shown.

[0036] Figure 26 The increased diffusion of stray light in the front surface of the corrugated virtual aperture and the back surface IOL of the microprism is shown.

[0037] Figure 27 The last peak of the microprism is shown.

[0038] Figure 28 A schematic diagram of at least a portion of an IOL is shown, the IOL having a central optical region surrounded by first and second annular regions. Detailed Implementation

[0039] Before further describing the invention, it should be understood that the subject matter described herein is not limited to the specific embodiments described, and therefore variations are naturally possible. It should also be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting. Unless otherwise defined, all technical terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0040] This invention discloses systems, apparatus, and methods for overcoming IOL defects, which improve visual quality by providing at least a phakic or aphakic IOL to correct defocus and astigmatism, reduce higher-order monochromaticity and chromatic aberration, and provide extended depth of field. The IOLs disclosed herein are sometimes referred to herein as Z+ lenses or Z+IOLs. Related systems and methods are described in U.S. Patent No. 10,285,807 and U.S. Patent Application Serial No. 16 / 380,622, both of which are incorporated herein by reference in their entirety.

[0041] The present invention now provides a description of the basic principles for reducing monochrome aberration and chromatic aberration and providing increased depth of field. Figure 1A A single converging lens 1 centered on the optical axis 2 is schematically shown. Incident rays 3 from a distant object are parallel to the optical axis and intersect the focal point 4 of the lens (based on the suffixes b, c, d, or e in the corresponding figures). If the lens power is chosen appropriately, the focal point coincides with the observation plane 5; otherwise, if the lens power does not match the position of the observation plane, the focal point will be in front of or behind the observation plane.

[0042] exist Figure 1A In the diagram, the focal point is in front of the observation plane. If all incident rays are traced at the same ray height as incident ray 3, then blur circle 6 lies on the observation plane 5. The observation plane is orthogonal to the optical axis and is therefore shown as a vertical line in the diagram. Blur circles 6 and 8 are shown in the plane of the diagram for visualization convenience; however, the blur circles are actually contained within the observation plane. Other parallel incident rays with ray heights less than incident ray 3 fall within blur circle 6. One such ray is parallel incident ray 7, which is closer to the optical axis than incident ray 3. Incident ray 7 also intersects the focal point 4 and then the observation plane 5. By tracing all incident rays with ray heights equal to incident ray 7, a blur circle 8 with a diameter smaller than blur circle 6 can be found.

[0043] Figure 1B The diagram shows... Figure 1A The same optical system is used, but now the incident light rays are directed towards an object closer to the optical system, as shown by the slopes on incident rays 3b and 7b. The effect is that the focal point 4 of the closer object (based on the corresponding pattern having sufficient a, b, c, or d) is now closer to the viewing plane, and the blur circles 6b and 8b are both smaller than their counters. Figure 1AWhile it involves a portion of the same element, the principle remains the same: the closer the light rays are to the optical axis and intersect with lens 1, the less blurring occurs on the viewing surface. In order to... Figure 1A and Figure 1B This simple optical structure is associated with the human eye. The converging lens 1 represents the principal plane of the eye's optics, including the cornea and the lens or artificial lens. The viewing plane 5 represents the retina. As shown, the focal point 4 is located in front of the viewing plane (retina), so this diagram applies to nearsighted or myopic eyes. The sizes of the blur circles 6 and 8 (or 6b and 8b) represent the amount of defocus on the retina, with smaller blur circle diameters providing sharper vision than larger ones.

[0044] It is important to note that the same relationship between the incident ray height and the size of the blur circle also applies to farsightedness or hyperopia. This is in Figure 2A and 2B The diagram schematically illustrates the light rays corresponding to farsightedness. Figure 2A Light rays from distant objects 3 and 7 and Figure 2B The smaller light heights of 3b and 7b result in a smaller blur circle on the retina (viewing surface).

[0045] Similarly, Figure 3A and 3B The same parallel ray height is shown with the blur circle diameter property applied to an emmetropic eye. For distant objects, focus 4e is now on the retina (because the eye is emmetropic), and the radii of blur circles 6e and 8e are zero. For closer objects, focus 4f is behind the retina, and the diameter of blur circle 8f corresponding to ray 7b, which is closer to the optical axis, is smaller than the diameter of blur circle 6f corresponding to ray 3b, which is farther from the optical axis.

[0046] Generally, the eye has aberrations, meaning that the focal point in the eye changes as the position of the incident light ray changes. But regardless of where the focal point is located (in front of, above, or behind the retina), as the height of the incident light ray decreases, the diameter of the circle of blur on the retina also decreases. In other words, for a given amount of defocus (refractive error) in the eye, vision improves as the height of the incident light ray decreases. This principle is used when someone strabismus causes their eyelids to block incident light rays that are off-axis of the eye in an attempt to see objects at a distance or near in focus more clearly.

[0047] Figure 1A-3B The ray tracing shown is for incident light of a single wavelength. For polychromatic light, there are multiple wavelengths. This is typically achieved by... Figure 4A and 4B The three different wavelengths of light shown are used to illustrate this. It is well known that for components of the eye and typical optical materials, the refractive index decreases as the wavelength of light increases.

[0048] exist Figure 4A In this structure, the converging lens 21 has an optical axis 22. The incident colored light 23 consists of three wavelengths: blue (450 nm), green (550 nm), and red (650 nm), roughly spanning the visible light spectrum. Due to the different refractive indices of the three wavelengths, the blue light 24 refracts more than the green light 25, and the green light refracts more than the red light 26. If the green light is focused, it then passes through the observation surface 27 at the optical axis. The dispersion of these three rays results in chromatic blurring 28 on the observation surface.

[0049] exist Figure 4B In this case, the incident chromatic aura 29 is at a lower height than chromatic aura 23 in 4A. This results in a slight chromatic aura blur 33 at the observation surface. Therefore, it is like... Figure 1A-3B Similar to monochrome blur, color blur decreases as the height of colored light decreases. This is achieved by considering the converging lens 21 as the principal plane of the eye and the viewing surface 27 as the retina. Figure 4A and Figure 4B The condition in the eye can be related to the eyes. The human eye typically has a large amount of color difference (the refractive power in the central visual range is about 1.0 to 1.2 diopters), so reducing this color difference can significantly improve the visual quality of the eye, especially as measured by contrast sensitivity.

[0050] In short, Figure 1A-4B This explains that lowering the light height reduces monochromatic and chromatic aberrations at the retina, thereby improving visual quality. This can be achieved by reducing the pupil diameter to block light rays that are further from the optical axis, or by distributing the light from these rays evenly and / or widely across the retina, so that more aberrant light contributes less light to the central retinal blur circle. Another characteristic of this effect is that as the light height decreases, the depth of field increases, such as... Figure 1B , 2B As shown in 3B.

[0051] Figure 5A A converging lens 34 with an optical axis 2 and an aperture 35 is shown. An incident parallel ray 36 passes just through the aperture and thus through the lens focal point 37, intersecting the observation plane 38. All parallel rays have a small circle of blur 39 that follows ray 36 on the observation plane. An incident parallel ray 40 is blocked by the aperture and therefore cannot continue to the observation plane, resulting in a larger circle of blur 41. Thus, the aperture, by reducing the height of the incident ray, reduces the blur diameter on the observation plane.

[0052] Figure 5BThe diagram illustrates a "virtual aperture." That is, it is not an actual aperture that blocks light, but its optical effect is nearly identical in central vision. In this diagram, a beam 40b incident on the virtual aperture propagates through the virtual aperture 42 and, through refraction, diffraction, scattering, and / or reflection, produces widely dispersed rays 43, thus contributing very little to stray light (blurred light) at any point on the viewing surface. This is the main operating mechanism of the disclosed IOL.

[0053] Exemplary optical design of IOL

[0054] Figures 6A-6C The design of an example IOL is shown, which uses optical principles to achieve the benefits of reducing monochrome aberration and chromatic aberration, as well as increasing depth of field. Figure 6A The front view of the IOL is shown, where the front view can be anterior view. Figure 6B The rear view of the IOL is shown, where the rear view can be a posterior view. Figure 6C A side view of the IOL is shown. The IOL includes a central optical zone 46 (with a back face 46b), which provides correction for defocus, astigmatism, and any other lens-related corrections, such as correction for spherical aberration. Typically, for IOLs using a virtual aperture, the diameter of the central optical zone is smaller than that of a conventional IOL. This results in a smaller central thickness, making the IOL easier to implant and allowing for a smaller corneal incision during surgery. The IOL includes a virtual aperture 48, which is positioned more peripherally outward relative to the central location of the central optical zone 46. Moving outward from the periphery of the virtual aperture 48, at least one IOL tactile element 50 (with a back face 50b) is located within the IOL. The tactile element 50 may be formed by one or more arms that extend peripherally outward to define the outermost edge of the IOL. In one example, the optical zone has a diameter of 1.5 mm. The tactile element 50 may 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 virtual surface can pass through the optical zone to form an image on the retina. The aperture surface is widely dispersed downstream of the IOL, facing and passing through the retina, such that the image includes an extended depth of field, and that the virtual aperture reduces monochromatic aberration and chromatic aberration in the image. The optical zone may include at least one of bifocal optics, trifocal optics, and multifocal optics.

[0055] A virtual aperture is connected to an optical region 46 via a first transition region 47 located at the peripheral edge of the optical region 46, such that the virtual aperture surrounds or partially surrounds the first peripheral region of the optical region. The haptic element may include a second peripheral region for positioning the intraocular lens within the eye. The first transition region is located at the periphery of the optical region 46. A second transition region 49 connects the haptic element 50 to the virtual aperture 48. The first transition region 47 and the second transition region 49 are configured to ensure continuity of the outer surface of the IOL on either side of the zero-order and first-order corresponding transition regions. A common method for implementing these transition regions is a polynomial function, such as a cubic Bessel function. Transition methods such as these are known to those skilled in the art. On the back side of the IOL are the central optical region 46b, the haptic element 50b, and the transition 47b between them. Figures 6A-6C The tactile shapes are not necessarily drawn to scale and are for illustrative purposes only. Other tactile shapes and dimensions known to those skilled in the art will also be appropriate. The first and second transition zones are not necessarily present in the IOL itself.

[0056] An IOL has a front surface and a rear surface, and components of the IOL, including an optical region 46, a first transition region 47, a second transition region 49, a virtual aperture 48, and a tactile element 50, may each have their own front and rear surfaces. The optical region 46 has a front optical surface that may include at least one multifocal region and / or a tortuous surface. At least a portion or region of the front and / or rear surfaces, such as in the virtual aperture or other parts of the IOL, may have a surface profile or shape through which a desired or predetermined effect of light transmission is achieved. In a non-limiting example, the surface profile of the front and / or rear surfaces includes regions with corrugated profiles, such as a wave-like or wavy shape forming a series of raised and lowered surfaces. Figure 12 An example embodiment showing the corrugated profile is provided, wherein a series of concentric annular corrugated regions are formed on the surface of a virtual hole. The corrugations can be, for example, annular corrugations or a series of annular corrugations radiating outward from a central location.

[0057] The corrugations (or other surface profiles) can be arranged in any of a variety of patterns on the rear and / or front surfaces of the IOL. In one embodiment, the surface profiles are arranged as a series of concentric, annular (or partially annular) shapes, patterns, or regions radiating from the center or other point on the IOL. In another embodiment, the surface profiles can be microprismatic shapes or a series of microcrystalline shapes arranged on the surface. Figure 13 An example embodiment of a microprism shape on a virtual aperture surface is shown. The front and / or rear surfaces may also be smooth surfaces. Figure 14 An example embodiment of a smooth surface with a virtual aperture is shown. Some example embodiments of microprism configurations are described below.

[0058] Virtual aperture and / or microprism regions can exist on the front and / or rear surfaces of the IOL. Furthermore, in some applications, a ring for the virtual aperture and a ring for the microprism region may be beneficial. Figure 28 An example of such an embodiment is shown, wherein the central optical region 2801 is surrounded by a first annular region 2802 and is in turn surrounded by a second annular region 2803. The first annular region may depict a corrugated virtual aperture and the second annular region may depict a microprism region, and vice versa. The rear surface may have similar two-ring structures, wherein the regions are the same as or opposite to those on the front surface. Furthermore, the two annular regions may or may not have the same range from the center of the IOL. The IOL may have any number of annular regions with surface profiles on its front or rear surfaces.

[0059] In other applications, having more than two such annular regions on the front and / or rear surfaces of the lens may be beneficial.

[0060] It should be understood that various combinations of surface profiles or smooth surfaces can be achieved between the front and rear surfaces of the IOL, for example, in the region of the virtual aperture. Figure 15 A table is displayed, which contains various combinations of surface profiles between the front and rear surfaces.

[0061] Surface profiles can achieve various effects regarding light passing through the IOL. For example, depending on the type of surface profile used, a surface profile can achieve wider or broader stray light propagation. Surface profiles can be used to diffuse stray light, directing it away from the focal point of the retina.

[0062] Example of detailed information about the optical area

[0063] The optical zone is configured to provide the eye with improved focused light. For most eyes, good vision is provided by implementing improved spectacle correction, i.e., the optical zone corrects spherical, cylindrical, and axial errors for the eye. Spherical, cylindrical, and axial corrections are collectively referred to as astigmatism correction. In addition to astigmatism correction, spherical aberration in the optical zone is also optimally reduced. Correction of spherical aberration means that all or substantially all parallel incident rays in the optical zone have the same focal point, regardless of ray height. For aphakic intraocular lenses, the shape of the optical zone is chosen to have an equal conical surface. Previous experience with this design shape and spherical aberration correction has shown that it is less sensitive to real-world positioning errors, such as lens tilt and eccentricity relative to the eye's optical axis.

[0064] To determine the astigmatism power of the optical zone used to correct astigmatism errors in a particular eye, clinicians use IOL power calculation programs or algorithms. IOL power calculation algorithms can be provided as standalone programs (such as software programs) or as part of an instrument that acquires some or all of the ocular measurements required to perform the IOL power calculation. These measurements typically include the refractive power of the cornea (corneal curvature), anterior chamber depth (measured from the cornea to the iris or lens), and axial length (measured from the cornea to the retina). Once the measurements are entered into the IOL power calculation algorithm, the theoretical power of the IOL is calculated. Currently, an available IOL power (typically quantized in 0.5 diopters) is chosen that approximates the theoretical power of the implanted eye.

[0065] Calculate the radius of curvature R of each meridian.

[0066] To work well with the IOL power calculation algorithm, the disclosed IOL power markings are ideally accurate when placed in the eye. Generally, the power markings include astigmatism correction, which requires calculating the two principal powers along the two orthogonal principal meridians. For astigmatism correction, it is written as:

[0067] Sphere + Cylindrical x-axis

[0068] The units for spherical and cylindrical surfaces are diopters, and the units for axes are degrees (0 to 180). The two main diopters, P1 and P2, are given by formula (1).

[0069] P1 = sphere

[0070] P2 = sphere + cylinder (1)

[0071] In this formula, optical power P1 acts along the meridian given by the axis, and optical power P2 acts along the meridian given by (axis + 90) modulus 180. To calculate the optical power of the main optical zone with equal surface optical power shapes, start with the lens manufacturer's formula given in formula (2).

[0072] (2)

[0073] Given the primary lens power PE in diopters, the optical zone center thickness d in millimeters, and the refractive index nIOL of the lens material (known to at least three decimal places), the IOL optical zone is given by formula (3).

[0074] (3)

[0075] Surface optical power for calculating refractive power P 1 and P 2所 The main parameters involved are in Figure 7 It is shown schematically in the diagram. Figure 7 The optical region (or rear) surface 53, passing through the center of the optical axis 51IOL of the front (or anterior) surface 52 and the rear surface, is schematically shown. The front and rear surfaces 52 and 53 are equal, meaning they are two conic sections with radii equal to their apex radii. ř 一个 In millimeters and conic constants ķ The front and rear surfaces separate at the center, with a center thickness of [missing information]. d The unit is mm54. The lens material has known properties. of In situ Refractive index n IOL 55. The medium surrounding the lens inside the eye has In situ Refractive index n EYE 56.

[0076] Once the principal focal length of the optical zone surface is obtained using formulas (1)-(3) P 1 and P 2 Then use formula (4) to calculate each meridian. θ The power.

[0077] (4)

[0078] Then, given the meridian θ Diopter (diopter), the radius of curvature of a surface in a meridian. R(θ) (mm) is calculated using formula (5).

[0079] (5)

[0080] In this formula,

[0081] nIOL = the refractive index of IOL material.

[0082] nEYE = the refractive index of the medium inside the eye (1.336),

[0083] P(θ) = Power in meridian θ

[0084] R(θ) = Meridian radius θ.

[0085] The surfaces of equal complex optical zones can be calculated using formulas (1)-(5), where each meridian θ has a radius of curvature R(θ). If cylinder = 0 in formula (1), the radius is constant R(θ) = R for each meridian.

[0086] Calculation of the optimal conic coefficient K for each meridian

[0087] To provide spherical aberration correction, each meridian profile is represented as a conic section and the conic constant K is optimized to best reduce spherical aberration. The conic section [3] is given by equation (6).

[0088] (6)

[0089] In this formula,

[0090] x = distance along the optical axis, in mm, positive to the right.

[0091] y = distance perpendicular to the optical axis, in mm, positive upward.

[0092] r = radius of curvature at the apex in mm.

[0093] K = conic constant (dimensionless), for a circle K = 0.

[0094] Solving for x (6) gives the equation for the sag of the curve, as shown in equation (7).

[0095] (7)

[0096] The derivative of the cone sag is given in formula (8).

[0097] (8)

[0098] The analytical derivative in Equation (8) can also be numerically approximated by those skilled in the art using difference operators such as forward, backward, or central difference equations, and can be a first-order or higher-order difference equation. This derivative is used to calculate the normalized tangent vector T(y), as shown in Equation (9).

[0099] (9)

[0100] As described below, the tangent vector is used to match the tangent vectors of the transition region to provide first-order continuity between the transition region and the curve profiles they connect.

[0101] Once the optimal conic constant K(θ) is obtained for a given meridian vertex radius R(θ), to minimize spherical aberration is calculated. In a previous method for optimizing the conic constant of an isoconical IOL optics (described in U.S. Patent No. 7,350,918), a single conic constant for the entire surface was found by considering only a single meridian and a single ray height. Optimization was performed using a Newton-Raphson iteration to set the longitudinal ray aberration of that single meridian / single ray height to zero. In the present case, the conic constant is optimized for each meridian. This optimization is performed using a dense set of incident ray heights along the meridian and finding the resulting ray height on the observation plane located at the back focal point of the optical region. The location of the back focal point is given in Equation (10).

[0102] (10)

[0103] In this formula,

[0104] nIOL = the refractive index of IOL material.

[0105] nEYE = the refractive index of the medium inside the eye (1.336),

[0106] P = diopter at meridian θ

[0107] BFL = Back focal length in millimeters.

[0108] During optimization, an exhaustive search is performed on the value of the conic constant K to find the value that minimizes the cost function E. This cost function E is given in equation (11).

[0109] (11)

[0110] n = indexer on the tracing ray (0 to N-1).

[0111] N = number of rays being tracked.

[0112] y0(n) = the height n of the incident ray at the front surface of the optical region.

[0113] y1(n) = the height of ray n on the observation plane located at the back focal point.

[0114] p = transverse ray error power, a scalar that controls the behavior of the cost function.

[0115] In the cost function equation, the lateral ray error y1(n) is weighted by its corresponding incident ray height y0(n) to describe the area of ​​the optical sector it represents. For the application, a suitable value for the lateral ray error power p is 3. This value is chosen as p=2 (specifying a typical Euclidean norm and relating it to RMS error) and p=∞ (i.e., the maximum error or infinite norm). Choosing this value for p provides an excellent error norm for the application because the maximum lateral ray error value is smaller than typical RMS optimization, but still retains the maximum error that might occur when most lateral ray error values ​​are smaller than the infinite norm. This exhaustive search optimization for K is performed in the range of K=(-1 to 0), where N=10,000 equidistant incident ray heights, in order to find the optimal K that retains 4 decimal places.

[0116] Figure 8 A single ray 57 is schematically shown in this IOL optimization calculation. An incident ray 58 with ray height y0 propagates from left to right onto the front surface 59 of the optical zone. When the outgoing ray 60 leaves the rear surface 61 of the optical zone, it intersects the observation surface 62 and then the optical axis 63. The longitudinal ray error 64 is the distance from the focal point 65 to the point where the outgoing ray intersects the optical axis. The lateral ray error 66 is the distance from the focal point 65 to the point where the outgoing ray intersects the observation surface 62. The values ​​used in the cost function equation are the height y0 of the incident ray 58 and the height y166 of the outgoing ray 60 when it intersects the observation surface 62.

[0117] The example value range for this optical region is as follows:

[0118] scope unit scope First choice spherical diopter From 5.0 to 40.0, with a step size of 0.5. all cylinder diopter Increment by 1.0 from 0.0 to 6.0, with a step size of 0.5. all axis Bachelor of Science 1 to 180, with a step size of 1. all Center thickness millimeters 0.4 to 1.0 0.6 Optical zone diameter millimeters 1.3 to 4.0 1.5、2.25、3.0

[0119] Calculation of optical zone diameter

[0120] The following are simple equations for estimating visual acuity for a given pupil diameter and spherical refractive error. They are given in equations (12 and 13).

[0121] (12)

[0122] (13)

[0123] A = visual acuity in arcminutes (A = Sd / 20), i.e., minimum resolution angle.

[0124] k = a constant determined by clinical studies, with an average value of 0.65.

[0125] D = Pupil diameter (mm)

[0126] E = spherical refractive error in diopters

[0127] Sd = Snellen denominator.

[0128] Assuming the second formula is more accurate for low levels of refractive error and gives a reasonable result when E=0, this gives A=1 minute in radians or 20 / 20.

[0129] Solving for E(13) yields equation(14).

[0130] (14)

[0131] Equation (13) yields the acuity A given a depth of field range (Ex2) (in diopters) and pupil diameter D. Equation (14) yields the depth of field range in diopters given the acuity A and pupil diameter D. For example, for:

[0132] Visual acuity 20 / 40, A = 40 / 20 = 2 arc minutes.

[0133] D=3.0mm,

[0134] k=0.65,

[0135]

[0136] Depth of field = 2E = 1.8D, using (13),

[0137]

[0138] Note that these equations for sensitivity and depth of field are approximations that do not include diffraction effects. Using A=2(20 / 40 sensitivity), approximate depth of field values ​​can be calculated for the following three principal diameters:

[0139] Pupil diameter (mm) Approximate depth of field (diopter) (2x) 1.5 1.78(3.55) 2.25 1.18(2.37) 3.0 0.89(1.78)

[0140] Detailed description of virtual aperture

[0141] The following variables are defined for the virtual aperture IOL.

[0142] variable definition Computed tomography Center thickness ET Edge thickness RM) The vertex radius of curvature m in the meridian K (meters) Conic constant in meridian m TF1W Front transition zone 1 width VAFW Front virtual aperture region width TF2W Front transition zone 2 width LD Lens diameter OZ Optical zone diameter TBW Post-transition zone

[0143] The virtual aperture is entirely or partially responsible for scattering incident light rays intersecting the front surface of the virtual aperture extensively across the retina. In an example embodiment, the virtual aperture includes alternating high-power positive and negative profiles on the front surface and a smooth curve connecting the rear surface of the optical zone to the haptic element on the rear surface. This in Figure 9 The figure shows the optical axis 67, center thickness 68, edge thickness 69, and surface markers P0-P9 of the IOL. Figure 9The outline represents the upper half of the IOL and is not necessarily drawn to scale. The front surface 76 shows the front optical zone between points P0 and P1, with an optical zone half-diameter (OZD / 2) 71. The first transition region of the front surface has a width of 72 and lies between points P1 and P2. The virtual aperture has a width of 73 and lies between points P2 and P3. The second transition region of the front surface has a width of 74 and lies between points P3 and P4. The front tactile surface has a width of 75 and lies between points P4 and P5. The rear surface 77 has a rear tactile surface width of 78 and lies between points P6 and P7. The rear transition region has a width of 70 and lies between points P7 and P8. The total lens half-diameter is 79. The nominal virtual aperture reference line is located at 80.

[0144] Start locating surface landmarks from P0 = (0, 0). Figure 9 In the diagram, the X-axis increases to the right, and the Y-axis increases upwards. These points have the following coordinates:

[0145] Surface markers

[0146]

[0147] Figure 10 The diagram shows details of the virtual aperture distribution of the IOL, which is not necessarily drawn to scale. Virtual aperture 43 is shown on the left side of the diagram as a continuous thick line with varying radii of curvature, alternating in shape from bottom to top as concave / convex / concave / ... The bottom point P2 of the diagram corresponds to... Figure 9 Point P2 in the graph. Similarly, vertex P3 in this graph corresponds to... Figure 9 Midpoint P3. The bottom left circular area is surrounded by a dashed circle, which is magnified on the right side of this figure. In the magnified part of this figure, the concave portion of the circle with surface profile VS0, the center VC0, the vertex VA0, the starting point VP0, and the ending point VP1 of the circle are shown. These three points VP1:VC0:VP0 form a right angle, as shown by the small square at VC0. The virtual aperture nominal baseline 81 is a vertical line containing the boundary points between alternating circular surface profiles VS0, VS1, etc. Knowing that this is a part of a circle with a radius of curvature r0, and having the following vector relationship:

[0148] (15)

[0149] (16)

[0150] (17)

[0151] In the example embodiment, there are an even number J, for example 14, alternating circular surface profiles in the virtual aperture profile. Each of these circular surface profiles VSj has its corresponding center VCj, starting surface point VPj, surface vertex VAj, ending surface point VP(j+1), and radius rj. Given a sequence of radii rj of length J and the width of the virtual aperture region VAFW, a scaling factor S is calculated. If all radii are multiplied by S, the virtual aperture perfectly fits its required width. This scaling factor is calculated using formula (18).

[0152] (18)

[0153] After the scaling factor is calculated, the sequence rj values ​​are multiplied by S to obtain a set of radii used to determine the final virtual aperture profile. The preferred set of virtual aperture radii is randomly selected within the range of 0.05 to 0.10 mm. The virtual aperture width is 2.05 mm, and the average radius per ring is 0.075 mm, approximately: week.

[0154] Below are example radii for 18 circles that provide a virtual aperture width of 2.05mm:

[0155] J numerical values J numerical values 0 0.060 9 0.068 1 0.071 10 0.119 2 0.095 11 0.067 3 0.081 12 0.060 4 0.109 13 0.091 5 0.070 14 0.096 6 0.102 15 0.070 7 0.078 16 0.087 8 0.065 17 0.063

[0156] Then, given a starting point P2 and a continuous circular profile, the circle of the virtual aperture profile is constructed to precisely fit the desired virtual aperture width.

[0157] In an alternative embodiment, the radii r of the continuous circular profiles are equal and the number of alternating circular surface profiles J and the width of the virtual aperture region VAFW are given in formula (19) as equal radii.

[0158] (19)

[0159] Detailed description of the transition zone

[0160] In an example embodiment, the front surface transition region of the IOL provides: (1) a smooth blend between the outer edge of the central optical region of the front surface and the inner edge of the virtual aperture of the front surface, and (2) a smooth blend between the outer edge of the virtual aperture of the front surface and the inner edge of the front surface of the haptic element. The rear surface transition region provides a smooth blend between the outer edge of the central optical region of the rear surface and the inner edge of the rear surface of the haptic element. These transition regions can generate a set of surface points for turning files or other manufacturing equipment (e.g., lasers).

[0161] To smoothly blend or connect the various regions of the lens, i.e., to provide at least zero-order and first-order continuity between these regions, cubic Bézier curves are employed. The smoothness of the transition regions prevents visual artifacts. The two-dimensional (and three-dimensional) parametric Bézier curve F(t) is given in Equation (20).

[0162] (20)

[0163] in:

[0164] n = the order of the Bézier curve; for a third-order curve, n = 3.

[0165] t = parameter variable from 0 to 1, because the curve moves from the first control point to the last control point.

[0166] pi = control point.

[0167] The blending function used here is a cubic Bézier curve, therefore there are four points numbered p0 to p3. The width of the transition region (in degrees) is given by the variable WT. The cubic Bézier curve passes through point p0 at t=0 and p3 at t=1. When the endpoints p0 to p3 are set to equal to the last point in the surface connected by the transition region (e.g., ...), ... Figure 9 When the control points p1 and p2 are considered (in the context of the curve), zero-order continuity is guaranteed. The derivative of the curve at point p0 is equal to the slope of the line from p0 to p1. The derivative of the curve at point p3 is equal to the slope of the line from p2 to p3. Therefore, it is important to place the control point p1 along a line passing through point p0 (the end of the curve in the previous region) and whose slope is equal to the slope of the previous curve at p0. Similarly, the placement of point p2 is also important. These constraints on the control points p1 and p2 ensure first-order continuity at the edges of the regions connected by the transition curves.

[0168] Four Bézier control points form the convex hull of the Bézier curve. The influence of intermediate control points p1 and p2 on the curve shape increases and decreases with varying distances from boundary points p0 and p3. The parameter FT (transition section) is used to control the position of these intermediate control points within the blend region.

[0169] Small FT values ​​(e.g., 0.1) keep intermediate control points p1 and p2 near their respective terminal control points p0 and p3. Small FT values ​​do not maintain the derivative of the blending curve at endpoints far into the blending region. Larger FT values ​​(e.g., 0.5) push intermediate control points closer to the middle of the blending region. Larger FT values ​​maintain the derivative of the blending curve further into the blending region. Thus, the FT can control the characteristics of the transition curve within the blending region.

[0170] To optimize or otherwise improve the smoothness of the transition curve and thus prevent visual artifacts, the cubic Bézier curve in the transition region can have minimum curvature at all points along the curve, except for maintaining zero-order and first-order continuity at the endpoints, as described above. The curvature of the cubic Bézier curve is calculated using formula (21).

[0171] (twenty one)

[0172] Equation (21) shows that the curvature C(t) at a point given the parameter variable t is the norm of the cross product of the first and second derivatives divided by the norm of the cube of the first derivative. The cubic Bessel vector function and its first and second derivatives are given in equations (22), (23) and (24).

[0173] (twenty two)

[0174] (twenty three)

[0175] (twenty four)

[0176] In these formulas, p0 to p3 are the four control points of the cubic Bézier curve. As mentioned above, points p1 and p2 are chosen such that the first derivatives at endpoints p0 and p3 match the region to be connected. The normalized tangent vectors at p0 and p3 are defined using formulas (25) and (26).

[0177] (25)

[0178] (26)

[0179] These normalized tangent vectors can also be obtained by directly evaluating the neighborhood of the region to be mixed at points p0 and p3. Then, when searching for the minimum curvature cubic Bézier curve, the internal control points p1 and p2 are set according to formulas (27) and (28).

[0180] (27)

[0181] (28)

[0182] In these formulas, s is the distance between endpoints p0 and p3, and frac is a scalar value between (0,1) used to minimize the curvature of all points along the Bézier curve in formula (20). For further illustration, Figure 11A The image shows two Bézier curves with endpoint positions p0 and p3 and tangent vectors T0 and T3. One curve has a significantly greater curvature than the other, which has been optimized to have a minimum maximum curvature. The corresponding curvature plot is shown in... Figure 11BThe information is provided in the text. Figure 11B The maximum curvature of the unoptimized Bézier curve is approximately 2.6, while the maximum curvature of the optimized Bézier curve is approximately 0.5. This corresponds to a radius of curvature of 0.4 for the high-curvature Bézier curve and 2.0 for the optimized Bézier curve. This not only results in a smoother transition curve and minimal visual artifacts, but it also allows for lathe cutting tool radii up to five times larger than those with greater curvature.

[0183] To summarize the calculation of the transition region of Bézier curves, the following steps are performed:

[0184] Set endpoints p0 and p3 as the corresponding endpoints of the equation of the surface profile to be connected.

[0185] Calculate the tangent vectors T0 and T3 at the endpoints using the equations of the surface profiles to be connected.

[0186] Perform an exhaustive search on frac in the range [0,1] to minimize the curvature C(t) in the range [0,1].

[0187] Use optimized frac values ​​to calculate interior points p1 and p2.

[0188] Use four Bezier points p0 to p3 to calculate the transition curve profile using formula (22).

[0189] The virtual aperture can be located on the back of the IOL instead of the front, or it can be located on both the front and back surfaces of the IOL. The same applies to the microprism area. The optical area shown in Figure 1 is biconvex, but the lens can be meniscus or biconcave, depending on the required refractive power of the lens and its intended use as a phakic or aphakic IOL.

[0190] Example microprism virtual aperture structure

[0191] Figure 16 An example profile of an extended depth-of-focus lens (IOL) is shown, illustrating a side view of the IOL lens, which is symmetrical about a horizontal intermediate axis. The IOL has a front surface and a rear surface. Due to its symmetry, only the upper half of the lens is described. The lens profile has an optical axis 161 passing through the center of the lens. The front surface has a front optical region 162, a corrugated virtual aperture region 163, and a tactile element 164. The rear surface has a transition region 165 connecting a microprism region 166 to the tactile element 164, a microprism region 166, a transition region 167 connecting the microprism region 166 to the optical region 168, and a rear optical region 168.

[0192] Figure 17An example profile is shown of the transition area connecting the microprism region 166 to the haptic element 164. The edge of the haptic element 164 is connected to at least one of the curved, circular, or rounded profiles of the outermost portion of the microprism region 166 via a rounded corner 1710.

[0193] Figure 18 The geometric details of an example rounded corner 1710 are shown. The rounded corner 1710 is specified by its center 1712, radius 1713, starting point 1714, and ending point 1715. To calculate the corner specification, the corner radius, the intersection point 1716 of the line segments 1717 and 1718 connected by the corner, and the unit-length direction vectors 1719 and 1720 parallel to line segments 1717 and 1718, respectively, are provided. We represent these given data as:

[0194] r = fillet radius, a scalar.

[0195] P = the intersection of the line segments, a vector of length 2.

[0196] D0, D1 = a unit-length direction vector parallel to the line segment, a vector with a length of 2.

[0197] The light rays 1721 and 1722, which are parallel to line segments 1717 and 1718 respectively, are constructed as follows.

[0198] (29)

[0199] in,

[0200]

[0201] Here, each ray is defined by its origin and a direction vector per unit length. The ray origins P0 and P1 are located at... Figure 18 The two rays are identified as elements 1723 and 1724. The intersection of these two rays is the center of the rounded circle, 1712. This intersection point 1712 is found by solving for the parameter t0 or t1 from equation (30) and then substituting that value into the ray equation (29) above.

[0202] (30)

[0203] In formula (30), the columns of the 2x2 matrix on the right contain vectors D0 and -D1. We denote the center C. The remaining fillet specifications correspond to... Figure 18 The points Pa and Pb of elements 1714 and 1715 are calculated using formula (31).

[0204] (31)

[0205] The rounded corners connecting the microprism region to the tactile region are configured to provide a smooth transition, preventing visual artifacts that might be present at that location in some abrupt designs. Other methods can also be used for this smooth transition, such as Bézier curves known to those skilled in the art.

[0206] Figure 19 An example geometry of the transition region connecting the microprism region to the optical region is shown. The edge of the optical region 1825 is connected to the first part of the microprism region 1826 by a rounded corner 1827.

[0207] Figure 20 The details of the rounded corner connecting the optical region to the microprism region are shown. The rounded corner is specified by its center 1928, radius 1929, start point 1930, and end point 1931. To calculate the rounded corner specification, the rounded corner radius is provided, and the start point 1930 at the edge of the optical region is connected by the rounded corner, the unit-length tangent vector 1932, and the slope 1926 of the microprism segment. The given data is represented as:

[0208] r = fillet radius, a scalar.

[0209] Pa = a vector of length 2 starting point.

[0210] T = A unit-length tangent vector with the same slope as the endpoints of the optical region, a vector of length 2.

[0211] s = slope of the microprism segment, a scalar.

[0212] The tangent vector T can be calculated analytically from an equation representing the distribution of the optical region (e.g., a conic equation) or numerically using a difference equation. The difference equation can be a forward difference equation, a backward difference equation, or a central difference equation, and can be a first-order or higher-order difference equation. For example, if the optical region has a circular profile, it can represent an astigmatic or glaucous optical region centered at point Co on the optical axis; in this case, the tangent vector T per unit length is given by equation (31b).

[0213] (31b)

[0214] Figure 20 The diagram also shows dashed lines 1933 and 1934. The area below line 1934 is the optical region, the area above line 1933 is the microprism region, and the area between lines 1933 and 1934 is the transition region realized as a rounded circle. The center of the rounded circle C1928 is found using equation (32).

[0215] (32)

[0216] To find the fillet specification endpoint 1931, locate the point on the circle where the slope of the microprism segment 1926 matches the slope of the fillet circle. The coordinates of this endpoint 1931 are given by formulas (33a) and (33b).

[0217] (33a)

[0218] (33b)

[0219] The rounded corners connecting the microprism region to the optical region are intended to provide a smooth transition and prevent visual artifacts that might be present at that location in some abrupt designs. Other methods can also be used for this smooth transition, such as Bézier curves known to those skilled in the art.

[0220] In the example embodiment, the microprism array profile is placed on the posterior surface of the IOL. The microprism profile works by using a combination of refraction of some light rays and total internal reflection of others, and some light rays will be both refracted and totally internally reflected. In the discussion below, the microprism array profile is located on the back of the intraocular lens, and light travels from left to right, i.e., into the eye.

[0221] Figure 21 An example of the basic microprism array profile is shown. The shaded portion of the array represents the interior of the intraocular lens (IOL), while the anterior surface of the IOL is not shown. The refractive index N1 inside the IOL is greater than the refractive index N2 outside the IOL. Typical values ​​for N1 and N2 are 1.459 and 1.336, respectively. Ray 2035 intersects the microprism surface at an intersection 2036 with a surface normal 2037. This incident ray 2035 forms an angle of incidence 2038 relative to the surface normal 2037. Snell's law describes how ray 2035 refracts at the intersection 2036 and is given in equation (34).

[0222] (34)

[0223] In this formula, the angle of incidence is A1 and the angle of refraction is A2. In the diagram, A1 corresponds to component 2038, and A2 corresponds to component 2039. For example, using typical values ​​for N1 and N2, if the angle of incidence 2038 is 45 degrees, then the angle of refraction 3209 is 50.6 degrees. Figure 21 The small amount of light reflected around point 2036 is not mentioned because it is generally negligible. Refraction works in this way until the angle of incidence 2038 is greater than the so-called critical angle αc. For angles of incidence greater than the critical angle, the light is reflected at intersection 2. The critical angle is calculated by equation (35).

[0224] (35)

[0225] Using the typical refractive index values ​​N1 and N2 given above, the critical angle is 66.3 degrees. Figure 21 In the equation, incident ray 2041 intersects the surface of the microprism at intersection point 2042 with surface normal 2043. This incident ray 2041 forms an angle of incidence 2044 relative to the surface normal 2043. If the angle of incidence is 70 degrees, then according to equation (35), the ray undergoes total internal reflection at surface point 2042, with a reflection angle 2045 equal to the angle of incidence 2044, and the reflected ray 2046 is the result. Figure 21 The continuous path of the reflected ray 2046 is not shown in the diagram because it is subsequently refracted by the surface of the microprism.

[0226] In the example embodiment, the microprism array spanning the microprism region is non-uniform. This non-uniformity is... Figure 22 As shown in [the image]. Figure 22 In the diagram, the total height of 2147 is the distance from the end of the optical zone at the bottom of the diagram to the beginning of the tactile element at the top of the diagram. Four semi-microprisms are used... Figure 22 As shown, the size of the microprisms decreases from the bottom to the top of the figure, while the bottom position of each microprism remains constant along a single X-value, as indicated by the vertical dashed line in the figure below. As the microprism size decreases, the slope of the upper and lower portions of the microprism remains constant.

[0227] All segment slopes 2148 are constant values ​​of 0.5 and all segment slopes 2049 are constant values ​​of -0.5. The reduction in size from the center of the lens (bottom of the figure) to the periphery (top of the figure) allows for a reduction in lens thickness from the center to the tactile component, a typical feature of IOLs. The height of a single microprism decreases geometrically from bottom to top. For example, the height 2150 of a microprism is equal to the height 2151 of the previous microprism multiplied by a scaling factor a, where the scaling factor is less than 1. In the literature, our scaling factor a is also called the common ratio, denoted by the symbol r, but since we have already used the symbol r to represent the fillet radius, we have chosen an alternative symbol a. Given the starting point PA2154 of the optical zone edge and the ending point PB2155 of the tactile origin, the microprism slope s, and the common ratio a, we calculate the geometrically scaled microprisms using the following method.

[0228] Starting point P is Figure 22 The first complete microprism 2156 shown in the figure is given by formula (36).

[0229] (36)

[0230] in:

[0231] The coordinates of PA are represented as (Ax, Ay).

[0232] The coordinates of PB are represented as (Bx, By).

[0233] The base height h02151 of the first microprism is given by formula (37).

[0234] (37)

[0235] The base height of this series of microprisms is given by formula (38).

[0236] (38)

[0237] The sum of the heights of each base gives the total height H, which is calculated using formula (39).

[0238] (39)

[0239] The approximate number N of individual microprisms can be calculated from formula (40).

[0240] (40)

[0241] Given an integer number of individual microprisms N calculated in formula (12), we refine the initial base width h0 so that we end exactly at point PB2155. This fine-tuning of the initial base width is performed using formula (41).

[0242] (41)

[0243] The peaks and valleys of each microprism point n=0,...N-1 are calculated using formula (42).

[0244] (42)

[0245] After locating these peaks and valleys, applications such as Figure 23 The peaks and valleys are shown with rounded corners. (Using a combination...) Figure 18 These fillets are calculated using the methods described in formulas (29)-(31). To ensure that these fillets follow the correct sign convention, valley fillets (concave surfaces) will have positive radii, while peak fillets (convex surfaces) will have negative radii.

[0246] For example, the first valley rounded corner is in Figure 24 It is displayed as component 2460. Figure 24 The vertical dashed line 2462 in the middle coincides with the vertex of each valley rounded corner and has the same x-coordinate value XV. The center CV2465 of each valley rounded corner has the same x-coordinate given by formula (43).

[0247] (43)

[0248] In this formula, rV It is the radius of the valley fillet. The y-coordinate of the center CV of each valley fillet is given by equation (42) for the corresponding Valley. n The point is given. The boundary point of the rounded circle is at... Figure 24 The coordinates of points P0 and P1 are represented as P02463 and P12464, respectively. The coordinates of points P0 and P1 are given in formula (44).

[0249] (44)

[0250] In these formulas, the subscript n represents the number of valleys. For example... Figure 24 As shown, the radius rV of the valley rounded corner is assigned a positive value.

[0251] For example Figure 24 For the peak fillet shown in component 2461, we first use equation (42) to find the peak, and then use equation (45) to find the center CP of the peak fillet.

[0252] (45)

[0253] In this formula, rP is the radius of the peak rounded corner circle. Similar to the valley start and end points, the start and end points P0 and P1 of the peak rounded corner circle are calculated using formula (46).

[0254] (46)

[0255] Figure 24 The center, start point, and end point of the peak fillet are shown for elements 2468, 2466, and 2467, respectively.

[0256] Figure 25 The diagram illustrates how light passes through the Z+IOL distribution, which has a corrugated front surface and a smooth rear surface. Figure 26 This demonstrates that when the back surface is replaced by a back surface containing microprism regions, the diffusion of light on the retina is improved.

[0257] As an alternative to the aforementioned rounded corners, those skilled in the art can use other transition methods, such as Bézier curves.

[0258] In some applications, using random fillet radii and / or microprism slope values ​​may be advantageous.

[0259] Example Implementation Values ​​and Value Ranges

[0260] In the example embodiment, specific values ​​are selected for the microprism features described above. Furthermore, these values ​​can also be selected from a reasonable range of preferred values. These values ​​and ranges are listed in the table below.

[0261] scope numerical values minimum Maximum Microprism region height 2.25 mm 1.5 mm 2.75 mm Valley corner radius 0.02 mm (Tool radius) 0.06 mm Peak fillet radius 0.01 mm 0.0 mm 0.06 mm Microprism slope 0.5 0.25 (Critical angle) Microprism to tactile fillet radius 0.05 mm (Tool radius) 0.06 mm Microprism to optical zone fillet radius 0.01 mm 0.0 mm 0.06 mm

[0262] PCO (Posterior capsule opacification) barrier

[0263] Posterior capsule opacification (PCO) is a possible complication after cataract surgery. To reduce cell migration into the virtual aperture or microprism region, sharp, square edges can be presented at the tactile point. Furthermore, the last peak in the microprism region does not necessarily have rounded corners. Such a sharp last peak... Figure 27 The peak is displayed as 2559.

[0264] To apply the above concepts to the surface of a Z+IOL, the following steps are performed. First, the central optical element of the intraocular lens is specified. In a non-limiting example, the diameter of the optical region is approximately 1.5 mm, falling between 1.4 and 1.6 mm. The power of this optical region varies between -10 and 40 D, or in units of 0.25 or 0.5 D. The cylindrical power of the toric IOL varies between 0.5 and 6.0 D, with an amplitude of 0.25 to 0.5 D.

[0265] Then, a virtual aperture is generated using the concept described in previous disclosures. The width of the virtual aperture region is approximately 2.0 mm.

[0266] The width of the transition area on the front surface is set to approximately 0.15 mm. The dimensions of the microprism area on the back are described in the table above.

[0267] Once the front and rear surfaces are specified, obtain individual profile samples from the center to the periphery of the IOL to specify the points of the lathe cutting file.

[0268] While this specification contains numerous details, these should not be construed as limiting the scope of the claimed invention or any potentially claimed scope, but rather as descriptions of features specific to particular embodiments. Certain features described in the context of individual 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 individually or in any suitable sub-combination in multiple embodiments. Furthermore, although the foregoing features may be described as functioning in certain combinations, or even initially claimed, one or more claimed combinations may be removed from the combination in certain circumstances, and the claimed combination may be for sub-combinations or variations thereof. Similarly, although operations are described in a specific order in the drawings, this should not be construed as requiring such operations to be performed in the specific order or sequence shown, or to perform all illustrated operations to obtain the desired result. Only a few examples and implementations are disclosed. Variations, modifications, and enhancements may be made to the described examples and implementations, as well as other implementations, based on the disclosure.

Claims

1. An intraocular lens for providing extended depth of field, the intraocular lens comprising: An optical region, comprising at least one front optical surface and at least one rear optical surface; A first peripheral region, which is located on the periphery relative to the optical region, includes a virtual aperture, the virtual aperture including a front virtual aperture surface and a rear virtual aperture surface; as well as A second peripheral region is positioned peripherally relative to a first peripheral region, the second peripheral region including a tactile element for positioning an intraocular lens within the eye, wherein the tactile element includes the outermost region of the intraocular lens; When an artificial lens is implanted into the eye, multiple beams of light incident on the anterior optical surface pass through the optical zone to form an image on the retina. Its features are: The artificial lens has a first surface profile on its anterior surface, the first surface profile being located on the virtual aperture, and the first surface profile including at least an annular region formed by corrugations located on the surface of the anterior virtual aperture; The artificial lens has a second surface profile on its posterior surface, which is located on the virtual aperture. The second surface profile includes at least one annular region formed by a microprism array located on the surface of the posterior virtual aperture. The microprism array is connected to the optical region by rounded corners. The microprism array is non-uniform. In this process, a second multiple beam of light incident on the surface of the anterior virtual aperture is widely dispersed from downstream of the artificial lens toward and through the retina, such that the image includes an extended depth of field, and further wherein the virtual aperture reduces aberrations in monochrome and color images.

2. The intraocular lens according to claim 1, wherein the corrugations comprise a series of concentric annular corrugated regions.

3. The intraocular lens according to claim 1, wherein the first surface profile and the second surface profile are concentrically arranged within the virtual aperture region.

4. The intraocular lens of claim 1, wherein the optical region is separated from the virtual aperture by a first transition region.

5. The intraocular lens of claim 4, wherein the first transition region comprises a smooth Bézier curve transition.

6. The intraocular lens of claim 1, wherein the radius of the rounded corner is between 0.01 mm and 0.06 mm.

7. The intraocular lens according to claim 1, wherein the slope of the microprism array is between 0.25 and 0.

5.

8. The intraocular lens of claim 1, wherein the diameter of the optical zone is between 1.3 mm and 3.0 mm.

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