Optimized multifocal wavefront for presbyopia correction

Abstract

Example embodiments include methods for forming sub-surface optical structures in ophthalmic lenses. A method may include defining a phase wrapped wavefront for an ophthalmic lens to diffract light to a plurality of focal points; defining a spherical wavefront configured to induce spherical aberration in the ophthalmic lens; and generating, based on the wavefront, an energy output parameter for forming a sub-surface optical structure in the ophthalmic lens using an energy source, where the sub-surface optical structure is configured for correcting presbyopia by providing an extended depth of focus that results in increased mid-vision quality. Also disclosed is an ophthalmic lens having a Fresnel earring that causes a phase wrapped wavefront with spherical aberration.

Description

[0001] This invention application is a divisional application of the invention patent application with international application number PCT / US2021 / 040697, international application date July 7, 2021, Chinese national phase application number 202180049124.7, entitled "Optimized Multifocal Wavefront for Presbyopia Correction".

[0002] Cross-references to related applications

[0003] This application claims priority to U.S. Provisional Patent Application Serial No. 63 / 049,277, filed July 8, 2020, which is incorporated herein by reference in its entirety for all purposes. Background Technology

[0004] Optical aberrations that reduce visual acuity are common. Optical aberrations are defects in the eye that reduce the focusing of light onto the retina. Common optical aberrations include lower-order aberrations (e.g., astigmatism, positive defocus (myopia), and negative defocus (hyperopia)) and higher-order aberrations (e.g., spherical aberration, coma, and trefoil).

[0005] Existing treatment options for correcting optical aberrations include eyeglasses, contact lenses, and corneal reshaping through laser eye surgery. Additionally, artificial lenses are typically implanted to replace the natural lens removed during cataract surgery.

[0006] Presbyopia can be defined as a gradual loss of near vision, or the ability to focus on nearby objects, that occurs naturally with age. Presbyopia becomes noticeable in patients as early as their 40s and may continue to worsen over time, until around age 65. As patients age, the lens gradually hardens and enlarges, often making it difficult for the lens to adequately accommodate (or change shape) to focus on nearby objects. Summary of the Invention

[0007] The following is a simplified overview of some embodiments of the invention to provide a basic understanding of the invention. This content is not a broad overview of the invention. It is not intended to identify key / determining elements of the invention or to describe the scope of the invention. Its sole purpose is to present some embodiments of the invention in a simplified form as a prelude to the detailed implementation presented later.

[0008] The embodiments described herein relate to ophthalmic lenses having at least one subsurface optical structure (e.g., a diffractive optical structure and / or a non-diffractive optical structure) with an enhanced refractive index value distribution. In many embodiments, the subsurface refractive index variation is formed by focusing femtosecond-duration laser pulses onto a target sequence of subsurface volumes of the ophthalmic lens. The refractive index of the annular optical structure varies radially relative to the optical axis up to an upper limit refractive index (e.g., providing any suitable phase transition of less than 1.0 wave). The refractive index of the annular optical structure is equal to the upper limit refractive index over a radius from the optical axis (e.g., at least 0.15 mm in length). In many embodiments, the refractive index of the annular optical structure is equal to the lower limit refractive index over a radius from the optical axis (e.g., at least 0.15 mm in length) (e.g., providing a phase transition of 0.0 wave). Fewer laser pulses can be used to form the enhanced refractive index value distribution compared to a corresponding refractive index value distribution determined by a ratio method. Furthermore, limiting the refractive index value to be equal to or less than the upper limit refractive index helps reduce damage caused by laser pulse sequences at a given pulse energy level, compared to forming corresponding subsurface optical structures using refractive index values ​​greater than the upper limit. The method described herein can be used to form (multiple) subsurface optical structures in any suitable ophthalmic lens, such as an intraocular lens, contact lens, cornea, eyeglass, and / or native lens.

[0009] In some embodiments, methods, systems, and apparatus are described for determining parameters for forming optical structures (e.g., subsurface optical structures) in ophthalmic lenses to improve patient vision. These parameters can be used to control an energy source to appropriately form the desired optical structure.

[0010] In many cases, presbyopia patients under the age of 45 can be classified as early presbyopia requiring relatively small correction; presbyopia patients between the ages of 45 and 55 can be classified as intermediate presbyopia requiring moderate correction; and presbyopia patients over the age of 55 (or those who have received non-accommodative focusing intraocular lenses (IOLs)) can be classified as late presbyopia requiring relatively large correction.

[0011] This document discloses a method for forming a subsurface optical structure in an ophthalmic lens to improve patient vision (e.g., for correcting presbyopia). In some embodiments, the method includes defining a first phase-wrapping wavefront corresponding to a first optical structure, the first optical structure being configured to cause the ophthalmic lens to diffract light to a plurality of focal points, wherein the first phase-wrapping wavefront is a wavefront having a first predetermined phase height (e.g., not equal to 1 wave); defining a first spherical wavefront, the first spherical wavefront being configured to induce a first spherical aberration in the ophthalmic lens; and generating energy output parameters for forming a first subsurface optical structure in the ophthalmic lens using an energy source based on the first phase-wrapping wavefront and the first spherical wavefront, wherein the first subsurface optical structure is configured to correct presbyopia by providing an extended depth of focus that produces increased intermediate visual quality.

[0012] In some embodiments, the method may include accessing a patient’s optical prescription, wherein the optical prescription includes one or more prescription parameters for refracting light directed toward the patient’s retina to improve vision; and generating a first variable wavefront based on the optical prescription, wherein the first variable wavefront includes at least one portion having a phase height of more than one wave; wherein generating the first phase-wrapped wavefront includes collapsing the first variable wavefront to a first predetermined phase height.

[0013] In some embodiments, the energy output parameter specifies multiple power levels corresponding to multiple optical zones on the ophthalmic lens. The method may include directing a first energy beam from an energy source to a first subsurface optical zone of the ophthalmic lens for a first duration, wherein the power level of the first energy beam is based on a corresponding power level specified by the energy output parameter; and directing a second energy beam from an energy source to a second subsurface optical zone of the ophthalmic lens for a second duration, wherein the power level of the second energy beam is based on a corresponding power level specified by the energy output parameter. The first and second energy beams may respectively alter the refractive index of the first and second subsurface optical zones, and wherein the first subsurface optical structure includes both the first and second subsurface optical zones.

[0014] In some embodiments, the first optical structure is configured to make the ophthalmic lens a bifocal lens with an added magnification of 2 diopters. In some embodiments, the first optical structure is configured to make the ophthalmic lens a bifocal lens with an added magnification of 1.5 diopters. In some embodiments, the first predetermined phase height is between about 0.5 and 0.6 waves. In some embodiments, the first spherical aberration is about –0.2 μm. In some embodiments, the first spherical aberration is about 0.2 μm.

[0015] In some embodiments, forming a subsurface optical structure includes directing an energy beam toward a volume of an ophthalmic lens to change the refractive index of that volume.

[0016] In some embodiments, the method may include defining a second phase-wrapping wavefront corresponding to a second optical structure configured to cause an ophthalmic lens to diffract light to a plurality of focal points, wherein the second phase-wrapping wavefront is a wavefront having a second predetermined phase height (e.g., not equal to one wave); defining a second spherical wavefront configured to induce a second spherical aberration in the ophthalmic lens; and generating energy output parameters for forming a second subsurface optical structure in the ophthalmic lens using an energy source, based on the second phase-wrapping wavefront and the second spherical wavefront. In some embodiments, a first subsurface optical structure is configured to correct a first stage of a patient's presbyopia, a second subsurface optical structure is configured to correct a second stage of a patient's presbyopia, and the second stage of the patient's presbyopia follows the first stage of the patient's presbyopia.

[0017] Ophthalmic lenses for improving vision (e.g., for correcting presbyopia in patients) are also disclosed, which in some embodiments may be performed using the described methods. In some embodiments, the ophthalmic lens may include a first subsurface optical structure comprising concentric Fresnel rings within the interior of the ophthalmic lens. Each of the Fresnel rings may define a volume having a desired refractive index. The first subsurface optical structure may be configured to: induce a first spherical aberration in the ophthalmic lens; and diffract light to multiple focal points based on a phase-wrapped wavefront having a first predetermined phase height (e.g., not equal to one wave).

[0018] In some embodiments, the ophthalmic lens is a patient's intraocular lens, contact lens, or cornea. In some embodiments, a first subsurface optical structure is configured to make the ophthalmic lens a bifocal lens with an increased magnification of 2 diopters. In some embodiments, the first subsurface optical structure is configured to make the ophthalmic lens a bifocal lens with an increased magnification of 1.5 diopters. In some embodiments, the first predetermined phase height is between about 0.5 and 0.6 waves. In some embodiments, the first spherical aberration is about -0.2 μm. In some embodiments, the first spherical aberration is about 0.2 μm.

[0019] In some embodiments, the ophthalmic lens includes a second subsurface optical structure. A first subsurface optical structure may be embedded in a first layer of the ophthalmic lens. The second subsurface optical structure may be embedded in a second layer of the ophthalmic lens. In some embodiments, the first subsurface optical structure is configured to correct a first stage of a patient's presbyopia, and the second subsurface optical structure is configured to correct a second stage of the patient's presbyopia. The second stage of the patient's presbyopia may occur after the first stage of the patient's presbyopia. Attached Figure Description

[0020] Figure 1 This is a plan view of an ophthalmic lens according to an embodiment, including a subsurface optical structure with an enhanced refractive index variation distribution.

[0021] Figure 2 yes Figure 1 A plan view of the subsurface optical structure of an ophthalmic lens.

[0022] Figures 3A to 3B An example wavefront showing parallel and converging light rays passing through a medium is shown.

[0023] Figures 3C to 3D An example wavefront that can simulate eye aberrations is shown.

[0024] Figure 3E A two-dimensional wavefront diagram and the corresponding first variable wavefront are shown.

[0025] Figure 3F The first phase wrapping wavefront corresponding to the first variable wavefront is shown.

[0026] Figure 4 The second phase-wrapped wavefront with a phase height of less than one wave is shown.

[0027] Figure 5 This illustrates a phase-wrapped wavefront (such as one with an optical phase height of less than one wave) that is phase-wrapped. Figure 4 The wavefront in the image is represented by a two-dimensional graph.

[0028] Figure 6 An example of an optical structure with diffraction properties is shown.

[0029] Figure 7 It is a graph showing the relative distribution of light between the near-vision focal point and the far-vision focal point when the phase height of the wavefront is adjusted between 0 and 1 waves.

[0030] Figure 8 A cross-section of an ophthalmic lens comprising a subsurface optical structure with multiple substructures is shown.

[0031] Figures 9A to 9BAn example conceptualization of an ophthalmic lens with multiple optical zones is shown.

[0032] Figure 10 An example method is shown for determining parameters for forming subsurface optical structures designed to improve patient vision.

[0033] Figure 11 An example of the progression of presbyopia in a patient is shown.

[0034] Figure 12 An example chart showing the progression of presbyopia is provided.

[0035] Figure 13 An example image quality metric is shown using multiple bifocal wavefronts across a range of refractive power.

[0036] Figure 14 This illustrates the concept of spherical aberration in a lens.

[0037] Figure 15 Example image quality measures for presbyopic patients with lenses having positive and negative spherical aberrations, compared to a control with zero spherical aberration.

[0038] Figure 16 It shows that Figure 13 The 2 diopter bifocal line and Figure 15 A curve diagram showing the superposition of spherical aberration lines and control lines.

[0039] Figure 17 The diagram shows lines corresponding to the image quality metrics of the three focal points further superimposed with the phase wrapper. Figure 16 The curve graph.

[0040] Figure 18 A graph is shown that includes several lines previously described, as well as lines corresponding to bifocal points with spherical aberration.

[0041] Figures 19A to 19B It shows the relationship with Figure 18 The cross section of the wavefront corresponding to a specific line.

[0042] Figure 20 This is a table showing example wavefronts that can be implemented for different stages of presbyopia.

[0043] Figure 21 An example method 2000 for forming subsurface optical structures in ophthalmic lenses for the purpose of correcting presbyopia in patients is shown.

[0044] Figure 22The simulated phase-wrapped wavefront for a design of 0.4 wave height is shown due to the practical limitations associated with the design of a phase-wrapped wavefront of 0.4 wave height in artificial or biological optical materials.

[0045] Figure 23 Showing the target Figure 22 The simulated phase-wrapped wavefront yields simulated through-focus retinal image quality.

[0046] Figure 24 Showing the target Figure 22 The phase-wrapped wavefront is obtained by simulating an amplified version of the phase-wrapped wavefront at 0.4 wave height.

[0047] Figure 25 Showing the target Figure 24 The simulated phase-wrapped wavefront is used to obtain the defocused retinal image quality.

[0048] Figure 26 The simulated defocused retinal image quality is shown, demonstrating the benefits of restoring near vision by scaling the design wavefront height. Detailed Implementation

[0049] In the following description, various embodiments of the invention will be described. Specific configurations and details are set forth for illustrative purposes to provide a thorough understanding of the embodiments. However, it will also be apparent to those skilled in the art that the invention may be practiced without these specific details. Furthermore, well-known features may be omitted or simplified so as not to obscure the described embodiments.

[0050] Figure 1 This is a plan view of an ophthalmic lens 10 according to an embodiment, comprising one or more subsurface optical structures 12 having a ring-shaped refractive index variation distribution. The one or more subsurface structures 12 described herein can be formed in any suitable type of ophthalmic lens, including but not limited to intraocular lenses, contact lenses, corneas, spectacle lenses, and native lenses (e.g., human native lenses). The one or more subsurface optical structures 12 having a ring-shaped refractive index variation distribution can be configured to provide appropriate refractive correction for each of a number of optical aberrations, such as astigmatism, myopia, hyperopia, spherical aberration, coma, and trefoil aberration, and any suitable combination thereof.

[0051] Figure 2 This is a plan view of the subsurface optical structure 12 of the ophthalmic lens 10. The subsurface optical structure 12 shown includes concentric circular substructures 14 separated by a median space or gap 16. Figure 2In this context, the size of the median space 16 is shown to be significantly larger than that in many practical embodiments. For example, the exemplary embodiment described herein has an outer diameter of 3.75 mm for the concentric substructures 14 and a median space 16 of 0.25 μm, resulting in 1875 concentric substructures 14 in an embodiment where the concentric substructures 14 extend to the center of the subsurface optical structure 12. Each of the concentric substructures 14 can be formed by focusing a suitable laser pulse onto a successive subvolume of the ophthalmic lens 10 to induce a change in the refractive index of the subvolume, such that each subvolume has a corresponding refractive index different from that of adjacent portions of the ophthalmic lens 10 surrounding the substructures 14 and not being part of any subsurface optical structure 12.

[0052] In many embodiments, a refractive index variation is defined for each sub-volume of the ophthalmic lens 10 that forms the subsurface optical structure 12, such that the resulting subsurface optical structure 12 will provide the desired optical correction when formed within the ophthalmic lens 10. The defined refractive index variation is then used to determine the parameters (e.g., laser pulse power (mW), laser pulse width (fs)) of the laser pulse that is focused onto the respective sub-volume to induce the desired refractive index variation within the sub-volume of the ophthalmic lens 10.

[0053] Although the substructure 14 of the subsurface optical structure 12 has a circular shape in the illustrated embodiment, the substructure 14 can have any suitable shape and refractive index variation distribution. For example, a single substructure 14 with an overlapping helical shape can be employed. Generally, one or more substructures 14 with any suitable shape can be distributed with intermediate spaces to provide the desired diffraction of light incident on the subsurface optical structure 12ss. More information about subsurface optical structures and the formation of such structures can be found in U.S. Provisional Application No. 63 / 001993, which is incorporated herein by reference in its entirety for all purposes.

[0054] In some embodiments, a system including one or more processors can be configured to determine parameters for forming one or more optical structures (e.g., subsurface optical structures) to improve or correct visual acuity. In some embodiments, one or more processors of the system can be configured to access a patient's first optical prescription. The first optical prescription may be issued by, for example, an optometrist. The first optical prescription may include one or more prescription parameters for refracting light directed toward the patient's retina to improve visual acuity. Prescription parameters may be determined based on any suitable measurement means. Prescription parameters may specify any suitable parameter for correcting or improving visual acuity. For example, prescription parameters may include refractive power values ​​for a sphere, cylinder, or axis. Prescription parameters may include parameters for correcting one or more of various low-order aberrations (e.g., myopia, hyperopia, astigmatism) and high-order aberrations (e.g., spherical aberration, coma, trilobal aberration).

[0055] Figures 3A to 3B Example wavefronts 305 and 306 are shown for parallel and converging light rays passing through a medium. A prescription for correcting or improving a patient's vision can essentially be described as a prescription for creating an optical structure that influences the wavefront, configured to modify the incident light rays before they reach the patient's retina. A wavefront is an imaginary surface with a constant phase. A wavefront can also be considered as a surface orthogonal to or perpendicular to the light rays passing through it. Figure 3A The planar wavefront 305 from the parallel light ray is shown. As is clearly visible, the wavefront 305 is perpendicular to the parallel light ray at each intersection. Figure 3B The spherical wavefront 306 from the converging light is shown. Figure 3B An ideal configuration of the eye is simulated, where light rays converge at a single point (on the retina 302). Each ray is perpendicular to the wavefront 307 at its corresponding intersection with the wavefront 307. The rays shown converge at a single point.

[0056] Figures 3C to 3D Example wavefronts 308 and 309 are shown that can simulate eye aberrations. Unlike Figure 3B Rays in the middle, Figure 3C The rays in the image do not converge at a single point on the retina 302 (e.g., at or near the macula). This non-convergence can cause vision problems (e.g., myopia) by preventing the image from focusing. Figure 3D The aberration wavefront 309 (a higher-order aberration) is shown in the simulation of another aberration of the eye. Similarly, each ray is perpendicular to wavefront 309 at its corresponding intersection with wavefront 309. And again, as shown in the figure, Figure 3DThe rays in the eye do not converge at a single point on the retina 302 (and in fact do not converge at all), thus causing vision problems. A suitable optical structure with a corrective wavefront can be used to correct problems caused by aberrations by, for example, refracting the light so that it converges at a single suitable point on the retina 302. Methods, apparatus, and systems for forming such optical structures are disclosed herein. Although this disclosure focuses on methods, apparatus, and systems for correcting ocular aberrations, it also envisions methods, apparatus, and systems for enhancing vision that can be considered normal.

[0057] Figure 3E A two-dimensional wavefront map 310 and a corresponding first variable wavefront 320 are shown. In some embodiments, one or more processors may use a first optical prescription to determine the wavefront of an optical structure for correcting or improving a patient's vision. In some embodiments, one or more processors may generate a wavefront map that can be visualized, for example, by the two-dimensional wavefront map 310. The outline of the two-dimensional wavefront map 310 may specify different optical phases corresponding to the wavefront. For example, different shading in the two-dimensional wavefront map 310 specifies different optical phases corresponding to the wavefront. In some embodiments, one or more processors may first calculate the Zernike coefficient (C) of defocus using the following equation. 2,0 Do it this way:

[0058] (1) C 2,0 = P*r max 2 / (4*sqrt(3)), where P is the magnification factor specified in the first prescription, r max It is the maximum radius of the optical zone.

[0059] The Zernike coefficient is a scalar quantity that can be expressed in micrometers. In some embodiments, a two-dimensional wavefront diagram can then be calculated using the following equation:

[0060] (2) W um = C 2,0 * sqrt(3) * (2 * ρ 2 - 1), where ρ is the normalized radial pupil coordinate (radial coordinate / r) max )

[0061] W um Provide values ​​(e.g., in micrometers) for each point in a two-dimensional wavefront plot. Reference Figure 3D This equation can be used to generate a two-dimensional wavefront diagram 310 for a specific optical prescription.

[0062] In some embodiments, one or more processors may be configured to generate a first variable wavefront based on a first optical prescription. (Reference) Figure 3DFor example, the first variable wavefront 320 can be generated based on details provided by a first optical formulation. The first variable wavefront describes the wavefront in units of waves relative to a specified wavelength. In some embodiments, the first variable wavefront includes at least one portion having a phase height greater than one wave. In some embodiments, the first variable wavefront can be generated based on a two-dimensional wavefront diagram. The first variable wavefront can be generated by plotting the W values ​​at each point... um Divide by the desired wavelength to determine relative to any desired wavelength. For example, the first variable wavefront can be determined relative to the center of the visible spectrum (e.g., 0.555 μm in sunlight). In this example, the following equation can be used to generate the first variable wavefront at 0.555 µm.

[0063] (3) W wv = W um / 0.555 μm

[0064] Figure 3F A first phase-wrapped wavefront 325 corresponding to a first variable wavefront 320 is shown. In some embodiments, one or more processors may be configured to phase-wrap the first variable wavefront, which may include collapsing the first variable wavefront to generate a first phase-wrapped wavefront. Phase-wrapping the first variable wavefront may involve collapsing the first variable wavefront into a wavefront having a predetermined phase height (i.e., the height from the peak to the trough of the wavefront). For example, refer to... Figure 3B The first phase wrapping wavefront 325 can have a phase height of 1 wave. Wrapping a variable wavefront phase to 1 wave does not cause a perceptible change in the diffraction or refraction of light, and therefore may be suitable, for example, for patients who only have myopia. An example Matlab algorithm for wrapping a phase to 1 wave phase height is shown below, where W555 = W wv And Wrap = 1:

[0065] while cnt == 0

[0066] W555( W555 < -Wrap ) = W555( W555 < -Wrap ) + Wrap;

[0067] if sum( W555(:) ​​< -Wrap ) == 0

[0068] cnt = 1;

[0069] end

[0070] end

[0071] cnt = 0;

[0072] while cnt == 0

[0073] W555( W555 > Wrap ) = W555( W555 > Wrap ) - Wrap;

[0074] if sum(W555(:) ​​> Wrap) == 0

[0075] cnt = 1;

[0076] end

[0077] end

[0078] In some embodiments, collapsing the first variable wavefront may include identifying a plurality of discrete segments of the first variable wavefront. In some embodiments, such as Figure 3F In this case, each of these discrete segments (e.g., 320-1 to 320-n) can be a circumferentially discrete segment extending radially around a two-dimensional wavefront pattern 310 of the ophthalmic lens. For example, discrete segment 320-1 in the first variable wavefront 320 can correspond to portion 310-1 in the two-dimensional wavefront 310, discrete segment 320-2 can correspond to segment 310-2, discrete segment 320-3 can correspond to segment 310-3, and so on. In other embodiments, the discrete segments may not be circumferential and the first variable wavefront may be segmented based on, for example, phase height. Figure 3F In the example shown, each of the discrete segments (325-1 to 325-n) is circumferential, and each discrete segment is adjacent to and concentric with another discrete segment. For example, discrete segment 325-2 is adjacent to and concentric with discrete segment 325-1 (similarly, discrete segment 325-3 is adjacent to and concentric with discrete segment 325-2, and so on). In some embodiments, one or more processors of the system can reduce the phase height of each discrete segment by a corresponding scalar so that the peak of the first discrete segment is at a desired phase height. For example, in Figure 3F In this process, the phase height of each discrete segment is reduced to a predetermined phase height of one wave, thereby generating a first phase-wrapped wavefront 325. As described above, collapsing the first variable wavefront 320 into a phase-wrapped wavefront 325 (which is collapsed into one wave) does not result in a perceptible change in diffraction or refraction, and light rays passing through an optical structure based on the collapsed phase-wrapped wavefront 325 behave substantially in the same manner as light rays passing through an optical structure formed based on the first variable wavefront 320. Figure 3E As shown, the resulting phase-wrapped wavefront may include a central discrete segment (e.g., discrete segment 325-1) and multiple surrounding circumferential, adjacent gratings (e.g., discrete segments 325-2 to 325-n).

[0079] Figure 4 A second phase-wrapped wavefront 427 with a phase height of less than one wave is shown. In some embodiments, the system can be configured to phase-wrap a first variable wavefront at a predetermined phase height not at one wave to generate a second phase-wrapped wavefront. For example, refer to... Figure 5 The phase-wrapped wavefront 427 shown has a predetermined phase height of less than one wave. As discussed further below, collapsing a wavefront to a phase height different from one wave results in diffraction, which can be useful for creating multifocal optical structures. Therefore, such a wavefront may be referred to herein as a "diffractive phase-wrapped wavefront". In some embodiments, the phase-wrapped wavefront may collapse with a phase height greater than one wave. The decision about whether the wavefront is collapsed to a phase height greater than or less than one wave can have some practical implications. For example, a phase wrapping greater than one wave can reduce diffraction chromaticity effects. However, a phase wrapping greater than one wave requires more available refractive index variation compared to a phase wrapping less than one wave, and any material used is affected by the possible refractive index variations within a given range, which can be a limiting factor (e.g., limited by material properties). However, in many cases, this may eventually be overcome by writing multilayers or volumetric filling, but limitations still exist. Therefore, there is a trade-off between phase wrapping with a phase height greater than or less than one wave. Whether the wavefront is wrapped by a phase of less than one wave or more can also affect the energy distribution of near / far vision (e.g., for presbyopic patients), and practitioners can control this as needed to achieve the desired effect.

[0080] Figure 5 Phase wrapping (such as) is shown with an optical phase height of less than 1 wave. Figure 4 A two-dimensional representation of the phase-wrapped wavefront 500 of wavefront 427 is shown. The phase-wrapped wavefront shown has an optical region with a diameter of 3.0 mm and a diffractive bifocal with increased magnification of 2.5 diopter (D). The diffractive bifocal wavefront is designed to have an optical phase height of 0.35 waves at a wavelength of 555 nm. As shown, the phase-wrapped wavefront 500 comprises five discrete circumferential segments, each with a phase height that gradually decreases from the inner boundary of the segment to the outer boundary (from 0.35 waves to 0 waves).

[0081] Figure 6 An example of an optical structure 610 with diffractive properties is shown. In some embodiments, an optical structure having a phase-wrapped wavefront with a phase height different from that of a single wave (e.g., less than one wave) has a diffraction effect that creates multiple focal points, which may be useful, for example, for correcting the vision of a patient with presbyopia. Figure 6As shown, light passes through optical structure 610 (optical structure 610 is an optical structure with diffraction properties), and the incident beam can be simultaneously focused at several positions along the propagation axis. This type of diffraction can be used to create multiple focal points, for example, to improve the vision of patients with presbyopia. For example, an optical structure with diffraction properties can have a first focal point for near vision and a second focal point for distance vision.

[0082] Figure 7 This is a graph 700 showing the relative distribution of light between the near-vision focus and the far-vision focus when the phase height of the wavefront is adjusted between 0 and 1 wave. In some embodiments, for conditions such as presbyopia, the system may generate a diffraction phase-wrapped wavefront (e.g., a phase-wrapped wavefront at less than 1 wave or greater than 1 wave), which is designed to provide high optical quality (e.g., good defocus image quality) for both far and intermediate near vision, but it should be understood that trade-offs may exist. Figure 7 An example representation of this tradeoff is shown below. As shown in hyperopia curve 710, as the phase height increases to 1 wavelet, the percentage of light distributed to the focal point of far vision through diffraction of the incident light decreases (and therefore the image quality of far vision generally decreases). In contrast, referring to near vision curve 720, as the phase height increases to 1 wavelet, the percentage of light distributed to the focal point of near vision increases (and therefore the image quality of near vision generally increases). In some embodiments, the desired distribution of this tradeoff can be specified in the optical prescription (e.g., as increased magnification) and can be determined based on any suitable patient-related factors. For example, a patient who frequently engages in highly detailed work (e.g., a watchmaker) may require a relatively high increased magnification (e.g., 4.0 diopters). A relatively low increased magnification (e.g., 1.0 diopters) may be suitable for a patient who does not engage in such highly detailed work. The diffraction phase wrapping wavefront can be generated using a prescription with this consideration to achieve the desired tradeoff.

[0083] In some embodiments, one or more processors may be configured to generate multiple wavefronts, for example, to correct multiple aberrations of the eye. In some embodiments, one or more processors may generate a second variable wavefront based on a second optical prescription, wherein the second optical prescription includes increased magnification for multifocal vision correction. The term “second optical prescription” does not necessarily refer to a single prescription, but may refer to one or more separate parameters for correcting aberrations different from those of a first optical prescription. For example, a patient may receive a single prescription from an optometrist for correcting near vision based on parameters of a first optical prescription and for correcting distance vision based on parameters of a second optical prescription (e.g., including increased magnification). In some embodiments, one or more processors may perform phase wrapping on the second variable wavefront, wherein phase wrapping on the second variable wavefront includes collapsing the second variable wavefront into a second phase-wrapped wavefront having a second predetermined phase height. The second predetermined phase height may be less than one wave to allow for diffraction effects as discussed above. In some embodiments, the first phase-wrapped wavefront may have a phase height of one wave, and the second phase-wrapped wavefront may have a phase height of less than one wave. In these embodiments, for example, a first phase-wrapped wavefront may be useful for correcting myopia, while a second phase-wrapped wavefront may be useful for correcting presbyopia.

[0084] Figure 8 A cross-section of an ophthalmic lens including a subsurface optical structure 810 is shown. In some embodiments, one or more processors may be configured to generate energy output parameters based on a first phase-wrapped wavefront for forming the first optical structure using an energy source. In some embodiments, the first optical structure may be configured to refract light directed toward a patient's retina to improve vision. In some embodiments, the optical structure may be a subsurface optical structure. For example, refer to... Figure 8 The cross-section shown can be a subsurface optical structure having multiple, potentially concentric, substructures 810. As discussed in further detail above, the subsurface optical structure can be achieved by appropriately focusing a laser pulse to a depth within the ophthalmic lens, thereby causing a change in refractive properties at the subvolumes within the ophthalmic lens.

[0085] Conventional methods for forming diffractive ophthalmic lenses involve creating Fresnel rings that project outwards from the outer surface of the lens. This configuration not only increases the lens's thickness profile but can also lead to problems with the lens's optical properties. For example, in the case of contact lenses, placing the Fresnel ring on the outer surface can cause errors in light diffraction or refraction because the tear film level can vary across the peaks and troughs of the Fresnel ring. Furthermore, placing the Fresnel ring on both the inner and outer surfaces of the contact lens can cause patient discomfort. Additionally, the ring on the outer surface of the lens can become a site of debris accumulation, leading to light scattering and loss of contrast.

[0086] Furthermore, conventional methods rely on variations in the thickness of the ophthalmic lens to provide its basic magnification. In these methods, the refractive index of the material throughout the lens can remain constant. This dependence on thickness necessarily means that a relatively thick lens has a relatively high basic magnification. For contact lenses, this can mean patient discomfort. For IOLs, this can mean increased patient risk during surgery and a higher likelihood of complications (e.g., because it may be more difficult to install the IOL in the lens capsule). In contrast, the disclosed method of creating subsurface optical structures using an energy system (e.g., a laser) does not rely on changing the thickness of the ophthalmic lens to obtain basic magnification. Instead, as explained above, the refractive index of a subvolume within the ophthalmic lens is modified to provide the lens's basic magnification, thereby allowing light to refract and / or diffract as needed. Finally, the use of an energy system, as described below regarding the optical region, provides significantly higher resolution compared to more conventional techniques such as cryo-lathes or injection molding.

[0087] Figures 9A to 9B An example conceptualization of an ophthalmic lens 900 with multiple optical zones is shown. In some embodiments, the ophthalmic lens can be divided into multiple pixels, each pixel corresponding to an optical zone. An optical zone can be a sub-region or sub-volume of the ophthalmic lens. This is in... Figure 9A As shown in the figure, Figure 9A An ophthalmic lens 900 is shown, divided into multiple pixels (e.g., pixels 910 and 920) in a grid pattern. Although Figure 9A The illustration shows a uniform square pixel, but pixels in this disclosure can be of any suitable shape (e.g., hexagonal, pentagonal, circular), and they can be non-uniform (e.g., they can be of different shapes and sizes). Pixel regions can correspond to the resolution of an energy delivery system (e.g., a laser system) configured to form an optical structure corresponding to a phase-wrapped wavefront. That is, a pixel region can correspond to a minimum region of a sub-region of an ophthalmic lens, at which the energy delivery system can focus an energy beam (e.g., a laser pulse) to change the refractive index of the sub-volume associated with the sub-region. Figure 9B Another conceptualization of the optical region is shown, in which the ophthalmic lens is not divided into discrete pixels. Instead, the ophthalmic lens is drawn using a coordinate system (e.g., a two-dimensional xy coordinate system or a three-dimensional xyz coordinate system, or a polar coordinate system (radius and angle)). For example, points 912 and 922 could each have corresponding coordinates in the coordinate system.

[0088] In some embodiments, the generated energy output parameters can specify the amount of power delivered by the energy delivery system in one or more optical zones. For example, refer to Figure 9A The energy output parameter can specify the power level (e.g., in watts) of one or more laser pulses delivered by the laser system at pixels 910 and 920. Similarly, refer to Figure 9B The energy output parameters can specify the power level at multiple coordinates (e.g., points 912 and 922) associated with the ophthalmic lens. In some embodiments, the generated energy output parameters can specify a duration during which the energy beam can be directed to one or more optical zones. For example, the energy output parameters can specify the pulse duration used to direct the laser beam to one or more optical zones. In some embodiments, the energy output parameters can specify the depth to which the energy beam is delivered when forming the optical structure. For example, the energy output parameters can specify that a first set of pulses will be delivered along a first layer of the ophthalmic lens to a first set of optical zones at a first depth, and can further specify that a second set of pulses will be delivered along a second layer of the ophthalmic lens to a second set of optical zones at a second depth. In this example, the first layer can be based on a wavefront wrapped with a phase of 1 wave collapse (e.g., for correcting myopia), and the second layer can be based on a wavefront wrapped with a phase of less than 1 wave collapse (e.g., for correcting presbyopia). The first set of pulses in this example can be associated with a first set of energy output parameters (e.g., power level, pulse duration, depth) for multiple optical zones, and the second set of pulses in this example can be associated with a second set of energy output parameters.

[0089] In some embodiments, one or more processors, along with the generated energy output parameters, may apply a calibration function to create a customized set of parameters for real-world conditions. The calibration function can depend on any suitable factor. For example, one or more processors may apply the calibration function based on one or more of the following: the material properties of the ophthalmic lens, the patient's sex, the patient's age, the depth at which the optical structure (e.g., a subsurface optical structure) will be formed in the ophthalmic lens, the number of layers, the distance between the different layers, and / or the properties of the energy source generating the energy output parameters (e.g., scan rate, numerical aperture, wavelength, pulse width, repetition rate, write depth, line spacing, scan architecture).

[0090] In some embodiments, one or more processors may be configured to generate energy output parameters for forming multiple optical structures. For example, one or more processors may generate energy output parameters for forming a first subsurface optical structure based on a first phase-wrapped wavefront with a phase height of 1 wave (e.g., for correcting myopia), and a second subsurface optical structure based on a second phase-wrapped wavefront with a phase height of less than 1 wave to cause light diffraction (e.g., for correcting presbyopia). In these embodiments, the result may be a multifocal ophthalmic lens configured to create multiple focal points within the eye. In some embodiments, these optical structures may be formed as different layers (e.g., in the cornea, contact lenses, or intraocular lenses). In other embodiments, one or more processors may generate parameters for forming a single optical structure as a monolayer that combines a first phase-wrapped wavefront and a second phase-wrapped wavefront, such that the monolayer has the effect specified by the two wavefronts.

[0091] In some embodiments, the system may further include an energy source configured to direct one or more energy beams toward an optical structure to form a first optical structure based on energy output parameters. In other embodiments, the system may not include such an energy source, and the energy output parameters may simply be sent to a different system that includes an energy source for forming the optical structure. In some embodiments, the energy source may be a laser source configured to deliver a target pulsed laser beam or a continuous-wave laser beam.

[0092] While the examples in this disclosure focus on the correction of standard spherical / cylindrical errors and / or presbyopia, this disclosure contemplates the generation of wavefronts that can be used to form optical structures for correcting any suitable aberrations (e.g., customized higher-order aberrations, peripheral errors of myopia progression). For example, wavefronts described by any combination of Zernike polynomials can be generated. Although this disclosure focuses on subsurface optical structures, this disclosure contemplates any suitable optical structure, such as non-subsurface optical structures.

[0093] Figure 10An example method 1000 for determining parameters for forming a subsurface optical structure to improve a patient's vision is illustrated. The method may include, at step 1010, accessing a first optical prescription for the patient, wherein the first optical prescription includes one or more prescription parameters for refracting light directed toward the patient's retina to improve vision. At step 1020, the method may include generating a first variable wavefront based on the first optical prescription, wherein the first variable wavefront includes at least one portion having a phase height greater than one wave. At step 1030, the method may include phase-wrapping the first variable wavefront, wherein phase-wrapping the first variable wavefront includes collapsing the first variable wavefront into a first phase-wrapped wavefront having a first predetermined phase height. At step 1040, the method may include generating energy output parameters based on the first phase-wrapped wavefront for forming a first subsurface optical structure in an ophthalmic lens using an energy source, wherein the first subsurface optical structure is configured to refract light directed toward the patient's retina to improve vision.

[0094] Where appropriate, certain embodiments may be repeated. Figure 10 One or more steps of the method. Although this disclosure will Figure 10 The specific steps of the method are described and shown as occurring in a specific order, but this disclosure contemplates... Figure 10 Any suitable steps of the method occur in any suitable order. Furthermore, although this disclosure describes and illustrates example methods for determining parameters for forming subsurface optical structures to improve patient vision (including...) Figure 10 This disclosure contemplates any suitable method (including any suitable steps, where appropriate, to determine parameters for forming subsurface optical structures for improving patient vision) for determining specific steps of the method, but also any suitable method (including any suitable steps, where appropriate, may include) for determining parameters for forming subsurface optical structures for improving patient vision. Figure 10 All, some, or none of the steps in the method Figure 10 (The steps of the method). Furthermore, although this disclosure describes and illustrates the implementation... Figure 10 The method may refer to a specific component, device, or system for a specific step, but this disclosure contemplates the execution of... Figure 10 Any suitable step of the method, any suitable component, device, or system, or any suitable combination thereof.

[0095] Figure 11An example of the progression of presbyopia in a patient is shown. In order to focus on objects near the eye, the eye's natural lens (e.g., the human lens) needs to be able to adjust or change its shape to properly converge light from the object onto the retina. This is achieved through the contraction of the ciliary muscle, which is coupled to the lens. As patients age, the natural lens tends to harden (decreased elasticity) and / or enlarge (axial and / or equatorial growth), making it increasingly difficult for the ciliary muscle to enable the lens to adjust properly. Therefore, patients may experience a reduced ability to focus on nearby or intermediate objects. This condition can be called presbyopia, and the example progression is shown in... Figure 11 As shown in the figure, Figure 11 The diagram illustrates the possible accommodative amplitude of a patient's natural lens as a function of age. Diopter can be defined as 1 / d, where d is the distance between the eye and the object (in meters). As shown, a patient at age 10 may have a relatively high accommodative amplitude, enabling them to properly adjust for objects as close as approximately 1 / 13 or 1 / 14 of a meter (i.e., 13 or 14 diopters). This accommodative amplitude gradually begins to decrease with age. Presbyopia typically begins to become noticeable around age 40. Figure 11 In the example, around age 40, the patient may be unable to properly adjust for objects farther than 1 / 4 meter away. Generally, patients under 45 years of age can be classified as early presbyopia requiring relatively minor correction. Presbyopia patients between 45 and 55 years of age can be classified as mid-stage presbyopia requiring moderate-level correction. Reference Figure 11 Patients in this age range may have developed presbyopia to the point where they are unable to properly adjust for objects farther than half a meter away. Presbyopia patients over 55 years of age (or those who have received non-accommodative intraocular lenses) can be classified as having advanced presbyopia requiring a relatively large level of correction. Reference Figure 11 After the age of 55, a patient's presbyopia may have progressed to the point where they are no longer able to adjust their vision to focus on objects less than 1 meter away.

[0096] Figure 12 An example chart showing the progression of presbyopia is provided. Figure 12 Typical accommodative capabilities are shown for early, intermediate, and late presbyopia (or those with monofocal non-accommodative IOLs). Figure 12The diagram also illustrates the appropriate increase in magnification that may be needed to improve near and / or intermediate vision for each corresponding stage of presbyopia progression. For example, early presbyopia may require an increase in magnification of 1 diopter, intermediate presbyopia may require an increase of 2 diopter, and late presbyopia may require an increase of 3 diopter. These increases in magnification can be provided, for example, by providing optical structures (e.g., subsurface optical structures within ophthalmic lenses) that enable the diffraction of wavefronts of light to refocus light rays from an object.

[0097] Figure 13 An example image quality metric across the refractive range using multiple bifocal wavefronts is shown. (Reference) Figure 13 Line 1310 illustrates an example of image quality as a function of defocus (in diopters) for a patient with presbyopia. The patient has relatively high image quality at low diopters corresponding to distance vision (e.g., an image quality value of approximately 0.9 at 0 diopters at infinity), while having relatively low image quality at high diopters corresponding to near vision (e.g., an image quality value of approximately 0.2 at 2 diopters at a distance of 0.5 meters). Figure 13 The image quality metrics shown (and in Figure 15 , Figure 16 , Figure 17 and Figure 18Similarly, the image convolution metric is referred to as the "image convolution metric," and many studies have shown that the image convolution metric is an excellent representative of high-contrast visual acuity. More information on such metrics can be found in the following references, which are incorporated herein by reference in their entirety for all purposes: Watson, Andrew B, et al., “Predicting visual acuity from wavefront aberrations”, Journal of Vision 8.4 (2008): 17-17; Zheleznyak, Len, et al., “Modified monovision with spherical aberration to improve presbyopia through-focus visual performance”, Investigative Ophthalmology & Visual Science 54.5 (2013): 3157-3165; Zheleznyak, Len, et al., “Impact of pupil transmission apodization on presbyopia through-focus visual performance with spherical aberration”, Investigative Ophthalmology & Visual Science 55.1 (2014): 70-77; and Kim, Myoung Joon et al., “Improving Through-Focus Visual Performance Using Primary And Secondary Spherical Aberrations”, Investigative Ophthalmology & VisualScience 53.14 (2012): 6332-6332.

[0098] A typical method to improve near vision in presbyopic patients is to use optical elements to diffract light to multiple focal points. For example, bifocal contact lenses, bifocal IOLs, or corneal modifications can be used to focus light from an object at two focal points—for example, a first focal point for nearby objects and a second focal point for distant objects. (Reference) Figure 13 Line 1320 corresponds to a conventional bifocal lens with an increased magnification of 2 diopters. As shown in the figure, the bifocal lens slate produces two peaks of high image quality—the first peak at 0 diopters and the second peak at approximately 2 diopters—corresponding to the two focal points of the bifocal lens. This generally results in an overall improvement in vision by allowing the patient to see relatively well around the two peaks, but it is still suboptimal because there is a large range between the peaks where image quality significantly decreases (intermediate vision).

[0099] In some embodiments, ophthalmic lenses with lower diopter values ​​can be used to shorten the range between peaks. For example, a 1.5 diopter bifocal lens can be used instead of a 2 diopter bifocal lens. Doing so shifts the image quality peaks toward better intermediate visual acuity compared to ophthalmic lenses with higher diopter values, but reduces image quality in the near vision range. In some embodiments, the ophthalmic lens can be made to correspond to a wavefront generated using the phase wrapping process described previously. That is, the wavefront of a typical bifocal lens can collapse to a predetermined phase height of less than one wave. For example, refer to Figure 13 Lines 1330 and 1340 correspond to a 1.5 diopter bifocal lens, with their wavefronts collapsed to 0.4 and 0.5 waves, respectively. As shown, the curvature of the image quality lines is adjusted by phase wrapping the wavefront. The optimal phase height and optimal magnification increase of the lens can be determined based on the patient's "visual diet," for example, by corresponding to the relative percentage of time the patient spends focusing at each distance on a daily basis. As clearly visible from these lines, achieving a diffractive wavefront typically involves a significant trade-off between near, intermediate, and far vision. That is, these diffractive wavefronts on their own usually do not produce optimal visual acuity across the entire visual range from near to far. For example, while lines 1330 and 1440, corresponding to the phase-wrapped wavefront, can be improvements over line 1320, which corresponds to a conventional bifocal lens, they still offer a range of intermediate vision with suboptimal image quality between their respective peaks.

[0100] Figure 14 This illustrates the concept of spherical aberration in lenses. Typically, all spherical lenses possess some degree of spherical aberration. For example... Figure 14As shown, lens 1410 with zero spherical aberration focuses all incident rays at a single focal point. In some embodiments, ophthalmic lenses may intentionally introduce spherical aberration to refocus light to help correct presbyopia. There are two general types of spherical aberration: negative spherical aberration and positive spherical aberration. Negative spherical aberration causes peripheral rays (light rays closer to the periphery of lens 1420) to refract by a smaller amount than central rays (light rays closer to the center or optical axis of lens 1420). Therefore, as... Figure 14 As shown, more central rays passing through lens 1420 reach the focal point before more peripheral rays. Positive spherical aberration causes the peripheral rays passing through lens 1430 to refract more than the central rays. Therefore, as... Figure 14 As shown, more peripheral rays passing through lens 1430 reach the focal point before more central rays.

[0101] Figure 15 Example image quality measures for presbyopic patients with lenses containing both positive and negative spherical aberrations are shown compared to a control with zero spherical aberration. Introducing spherical aberrations (both positive and negative) typically reduces image quality for distance vision but improves image quality for near and intermediate vision compared to a control. For example, reference... Figure 15 Lines 1520 and 1530, corresponding to positive and negative spherical aberration respectively, produce a decrease in image quality at the limit of distance vision (e.g., at 0 diopters) compared to control 1510, and an increase in image quality in the more intermediate and closer ranges (e.g., after approximately 0.4 diopters) compared to control 1510. (As from...) Figure 15 It is clearly visible that positive and negative spherical aberrations have their own trade-offs (for example, positive spherical aberration, as shown by line 1520, produces better intermediate vision but worse near vision, as shown by line 1530, for example). Figure 15 As shown, although spherical aberrations can be used to provide improvements over a control with zero aberrations, their ability to provide an extended range of high image quality from near to far vision is generally limited. That is, while they offer some gain in far vision, it decreases as one moves into near and / or intermediate vision.

[0102] Figure 16 It shows that Figure 13 The 2 diopter bifocal line 1320 and Figure 15 A curve plot showing the superposition of spherical aberration lines 1520, 1530 and the control line 1510. (See also...) Figure 16As can be seen in the example, the image quality measure of the bifocal line 1320 (e.g., at and near the 2 diopter peak) provides improvement for near and / or intermediate visual acuity loss occurring on the spherical aberration lines 1520, 1530. Furthermore, the image quality measure of the spherical aberration lines 1520, 1530 provides improvement for the valleys between the peaks of the bifocal line 1320 (e.g., between approximately 0 and 2 diopters). Therefore, spherical aberration and multifocality (e.g., bifocality) have properties that can complement each other. Embodiments of this disclosure attempt to create lenses corresponding to a unified wavefront that combines both properties, as will be explained below.

[0103] Figure 17 The diagram shows lines corresponding to the image quality metrics of the three focal points further superimposed with the phase wrapper. Figure 16 The graphs show the curves. Lines 1710 and 1720 both correspond to trifocal points centered at 1 diopter and 2 diopter, but line 1710 corresponds to a trifocal point with a phase wrap of 0.6 waves, while line 1720 corresponds to a trifocal point with a phase wrap of 0.5 waves. As shown, the trifocal points offer an improvement over the bifocal point corresponding to line 1610 in the range between 0 diopter and 2 diopter. For example, the trifocal points provide an additional peak at 1 diopter, and due to their respective phase wraps, they generally reduce the image quality degradation between their peaks (i.e., between the peaks at 0 diopter and 1 diopter, and between the peaks at 1 diopter and 2 diopter, in the example shown). However, the degradation between peaks may not allow for consistent image quality, which may be perceptible to the patient, and therefore may still be undesirable in providing a seamlessly extended visual range.

[0104] Figure 18 A graph is shown that includes several previously described lines and lines 1810 and 1820 corresponding to the phase-wrapped wavefronts (in 0.5 waves) of both defocus (1.5 diopters and 2.0 diopters, respectively) and spherical aberration. Line 1810 corresponds to a 1.5 diopters bifocal lens with –0.2 μm spherical aberration. Line 1820 corresponds to a 2 diopters bifocal lens with –0.2 μm spherical aberration. Figure 18 As shown, lines 1810 and 1820 generally provide high and consistent image quality over a large visual range. For example, line 1810 provides relatively high image quality up to about 2 diopters, with image quality remaining relatively constant for most of this range. Similarly, line 1820 provides relatively high image quality up to about 2.5 diopters, also remaining relatively constant (but with a slight decrease) for most of this range. In contrast, other lines exhibit a sharp drop in image quality at one or more points along this range.

[0105] Figures 19A to 19B It shows the relationship with Figure 18 The cross sections of the wavefronts corresponding to lines 1810 and 1820. Figure 19A Corresponding to Line 1810 (a 1.5 diopter bifocal lens with a spherical aberration of –0.2 μm), Figure 19B This corresponds to line 1820 (a 2 diopter bifocal line with spherical aberration of –0.2 μm). As shown in the figure, these wavefronts have been phase-wrapped with a phase height of 0.5 waves.

[0106] In some embodiments, the wavefront can be phase-wrapped as previously described. Any suitable phase height can be predetermined for the phase wrapping. In some embodiments, the phase height can be less than one wave. For example, the wavefront can be phase-wrapped to 0.5 or 0.6 waves. As previously discussed, the phase height chosen for the phase wrapping affects how light energy is distributed between near, intermediate, and far vision. For example, refer to... Figure 7 The example diagram shows that at a phase height of 0.5 waves, light is evenly distributed between near and far vision. As the phase height increases towards 1 wave, more light is distributed towards near vision rather than far vision. In contrast, as the phase height decreases towards 0 waves, more light is distributed towards far vision rather than near vision. The appropriate phase height can be determined for a patient based on, for example, a “visual diet” as previously explained.

[0107] Figure 20 This is a table showing example wavefronts that can be implemented for different stages of presbyopia. As previously explained, presbyopia typically develops with age, and patients can be broadly characterized as early, intermediate, and late-stage presbyopia. As previously stated, any suitable wavefront can be implemented by the described system to form the necessary ophthalmic lens. Figure 20 The document records some example wavefront characteristics for each stage. Optical structures (e.g., subsurface optical structures within the ophthalmic lens) can be formed using an energy source (e.g., a laser) to achieve any suitable wavefront, thereby correcting the patient's vision as needed.

[0108] In some embodiments, these implementations can be phased in as presbyopia progresses. For example, an ophthalmic lens with a wavefront adapted for early presbyopia can be used to treat a patient with early presbyopia. Once the patient's presbyopia has progressed to the intermediate stage, the same patient may later receive further treatment adapted for intermediate presbyopia. Similarly, once the patient's presbyopia has progressed to the late stage, the same patient may later receive further treatment adapted for late presbyopia. The systems and methods described herein are advantageous because they allow for this phased approach even in corneal or IOL ophthalmic lenses. For example, a patient with an IOL designed for early presbyopia can receive further treatment for intermediate or late presbyopia without requiring a new IOL implantation surgery. Alternatively, the energy system (e.g., a laser system) can be used to simply modify the refractive index of the IOL to achieve a suitable wavefront as needed.

[0109] Figure 21 An example method 2100 for generating parameters for forming a subsurface optical structure in an ophthalmic lens to correct presbyopia in a patient is illustrated. The method may include, at step 2110, generating a first phase-wrapping wavefront corresponding to a first optical structure configured to cause the ophthalmic lens to diffract light to multiple focal points, wherein the first phase-wrapping wavefront is a wavefront having a first predetermined phase height of less than one wave. The first phase-wrapping wavefront may be generated based on the patient's optical prescription, wherein the optical prescription includes one or more prescription parameters for refracting light directed toward the patient's retina to improve vision. A first variable wavefront may be generated according to the optical prescription, wherein the first variable wavefront includes at least one portion having a phase height of more than one wave. The variable wavefront may then be collapsed to the first predetermined phase height to generate the first phase-wrapping wavefront. At step 2120, the method may include generating a first spherical wavefront configured to induce a first spherical aberration in the ophthalmic lens. The first spherical wavefront can also be based on a first optical prescription and can be generated based on a simulation of an image quality metric produced by combining the first spherical wavefront with a first phase-wrapping wavefront. The optimal spherical wavefront and phase-wrapping wavefront can be determined based on the simulation, taking into account the patient's lifestyle and the "visual diet" as explained above. At step 2130, the method may include generating energy output parameters based on the first phase-wrapping wavefront and the first spherical wavefront for forming a first subsurface optical structure in an ophthalmic lens using an energy source, wherein the first subsurface optical structure is configured to correct presbyopia by extending the depth of focus, allowing for increased intermediate visual quality.

[0110] Where appropriate, certain embodiments may be repeated. Figure 21 One or more steps of the method. Although this disclosure will Figure 21The specific steps of the method are described and shown as occurring in a specific order, but this disclosure contemplates... Figure 21 Any suitable steps of the method occur in any suitable order. Furthermore, although this disclosure describes and illustrates example methods for generating parameters for forming subsurface optical structures in ophthalmic lenses for correcting presbyopia in patients (including…),… Figure 21 This disclosure contemplates any suitable method (including any suitable steps, which may include, where appropriate, specific steps) for generating parameters for forming subsurface optical structures in ophthalmic lenses to correct presbyopia in patients. Figure 21 All, some, or none of the steps in the method Figure 21 (The steps of the method). Furthermore, although this disclosure describes and illustrates the implementation... Figure 21 The method may refer to a specific component, device, or system for a specific step, but this disclosure contemplates the execution of... Figure 21 Any suitable step of the method, any suitable component, device, or system, or any suitable combination thereof.

[0111] Adjustments made to implementation limitations

[0112] As described herein, a designed phase-wrapped wavefront, as an abstract construct, can have a vertical step, where the wavefront slope undergoes an abrupt, infinite change. However, realizing a designed phase-wrapped wavefront in artificial or biological materials can lead to discrepancies between the resulting optical correction and the optical correction corresponding to the designed phase-wrapped wavefront. These optical discrepancies can be generated by low-pass filtering of the designed phase-wrapped wavefront, as referred to herein. Low-pass filtering of the designed phase-wrapped wavefront can have numerous causes, including but not limited to the magnitude of the laser point spread function, the volume of the laser-induced refractive index change (LIRIC) in the artificial or biological optical material, and / or post-LIRIC changes in the artificial or biological optical material (e.g., bioremodeling, swelling, etc.).

[0113] To evaluate the impact of low-pass filtering, Matlab was used to simulate the image quality (RIQ) of defocused retina with different amounts of low-pass filtering (full width at half maximum (FWHM) from 2 μm to 188 μm) using a Gaussian function (monochrome at 550 nm, pupil diameter of 3 mm, diopter-increased magnification diffraction multifocal wavefront, and image convolution metric). Figure 22 The simulated phase-wrapped wavefronts 2210, 2220, 2230, 2240, 2250, 2260, and 2270 are shown for the desired 0.4 wave height due to the influence of different amounts of low-pass filtering. As shown in the figure, for each increase in the magnitude of the low-pass filtering, the peak wave height of the resulting effective phase-wrapped wavefront gradually decreases in amplitude from the designed 0.4 wave height. Figure 23 Showing the target Figure 22 The simulated defocus (RIQ) values ​​obtained from the phase-wrapped wavefront were 2310, 2320, 2330, 2340, 2350, 2360, and 2370. The simulated defocus RIQ showed a near vision benefit and a gradual decrease in near vision RIQ, and the distance RIQ increased with the increase of the low-pass filter amplitude, eventually recovering to the pre-treatment RIQ at the highest amplitude of the low-pass filter.

[0114] To compensate for the impact of low-pass filtering on out-of-focus (RIQ), the design peak waveform height can be increased or scaled by an appropriate amount. For example, Figure 24 Showing the target Figure 22 The simulated phase-wrapped wavefronts with a design height of 0.4 were amplified to obtain phase-wrapped wavefronts of 2410, 2420, 2430, 2440, 2450, 2460, and 2470. The amplified version of the phase-wrapped wavefront design with a design height of 0.4 was amplified by (1.0 / 0.4) to increase the wavefront peak from 0.4 to 1.0. Figure 24 The simulation of a phase-wrapped wavefront with a design height of 0.4 is shown, with varying amounts of low-pass filtering applied. As the figure shows, the peak wave height of the resulting effective phase-wrapped wavefront gradually decreases from 1.0 wave height with increasing low-pass filtering. Figure 25 Showing the target Figure 24 The simulated defocus (RIQ) values ​​of the phase-wrapped wavefront were obtained at 2510, 2520, 2530, 2540, 2550, 2560, and 2570. For different amounts of low-pass filtering, the simulated defocus RIQ for the amplified version showed a near-vision benefit and near RIQ increase relative to the design phase-wrapped wavefront of 0.4 wave height. Figure 26 The simulated defocused retinal image quality is shown, demonstrating the near vision benefits that can be restored by scaling the designed wavefront height. As illustrated, the amplified version of the designed phase-wrapped wavefront at a height of 0.4 exhibits comparable defocus RIQ 2620 at a higher level of low-pass filtering (94 μm FMHM) compared to a lower level of low-pass filtering (2 μm FWHM). Therefore, amplification of the designed phase-wrapped wavefront can be used to compensate for the effects of the resulting low-pass filtering associated with the phase-wrapped wavefront physically induced in artificial or bio-optical materials.

[0115] Example 1 is a method for generating parameters for forming a subsurface optical structure in an ophthalmic lens to correct presbyopia in a patient. The method of Example 1 includes: defining a first phase-wrapping wavefront corresponding to a first optical structure, the first optical structure being configured to cause the ophthalmic lens to diffract light to a plurality of focal points, wherein the first phase-wrapping wavefront is a wavefront having a first predetermined phase height; defining a first spherical wavefront, the first spherical wavefront being configured to induce a first spherical aberration in the ophthalmic lens; and generating energy output parameters based on the first phase-wrapping wavefront and the first spherical wavefront for forming the first subsurface optical structure in the ophthalmic lens using an energy source, wherein the first subsurface optical structure is configured to correct presbyopia by providing an extended depth of focus that produces increased intermediate visual quality.

[0116] Example 2 is the method of Example 1 (or the method of any other previous or subsequent examples, alone or in combination), wherein the first predetermined phase height is not equal to 1 wave.

[0117] Example 3 is the method of Example 1 (or the method of any other previous or subsequent examples, alone or in combination), further comprising: accessing a patient's optical prescription, wherein the optical prescription includes one or more prescription parameters for refracting light directed toward the patient's retina to improve vision; and defining a first variable wavefront based on the optical prescription. In Example 3, the first variable wavefront includes at least one portion having a phase height of more than one wave. In Example 3, defining the first phase-wrapped wavefront includes collapsing the first variable wavefront to a first predetermined phase height.

[0118] Example 4 is a method of Example 1 (or any other method of previous or subsequent examples, alone or in combination), wherein an energy output parameter specifies multiple power levels corresponding to multiple optical zones on an ophthalmic lens. Example 4 further includes: directing a first energy beam from an energy source to a first subsurface optical zone of the ophthalmic lens during a first duration, wherein the power level of the first energy beam is based on a corresponding power level specified by the energy output parameter; and directing a second energy beam from an energy source to a second subsurface optical zone of the ophthalmic lens during a second duration. In Example 4, the power level of the second energy beam is based on a corresponding power level specified by the energy output parameter. In Example 4, the first and second energy beams respectively change the refractive index of the first and second subsurface optical zones. In Example 4, the first subsurface optical structure includes both the first and second subsurface optical zones.

[0119] Example 5 is a method of any one of Examples 1 to 4 (or any other method of any previous or subsequent example, alone or in combination), wherein a first optical structure is configured to make the ophthalmic lens a bifocal lens with an increased magnification of 2 diopters.

[0120] Example 6 is a method of any one of Examples 1 to 4 (or any other method of the preceding or subsequent examples, alone or in combination), wherein the first optical structure is configured to make the ophthalmic lens a bifocal lens with an increased magnification of 1.5 diopters.

[0121] Example 7 is a method of any one of Examples 1 through 4 (or any other method of any previous or subsequent example, alone or in combination), wherein the first predetermined phase height is between about 0.5 and 0.6 waves.

[0122] Example 8 is the method of Example 7 (or the method of any other previous or subsequent examples, alone or in combination), where the first spherical aberration is approximately -0.2 μm.

[0123] Example 9 is the method of Example 7 (or the method of any other previous or subsequent examples, alone or in combination), where the first spherical aberration is approximately 0.2 μm.

[0124] Example 10 is a method of any one of Examples 1 through 4 (or any other method of the preceding or subsequent examples, alone or in combination), wherein forming a subsurface optical structure includes directing an energy beam toward a volume of an ophthalmic lens to change the refractive index of that volume.

[0125] Example 11 is a method of any one of Examples 1 to 4 (or any other method of previous or subsequent examples, individually or in combination), further comprising: defining a second phase-wrapping wavefront corresponding to a second optical structure, the second optical structure being configured to cause an ophthalmic lens to diffract light to a plurality of focal points, wherein the second phase-wrapping wavefront is a wavefront having a second predetermined phase height; defining a second spherical wavefront, the second spherical wavefront being configured to induce a second spherical aberration in the ophthalmic lens; and generating energy output parameters for forming a second subsurface optical structure in the ophthalmic lens using an energy source based on the second phase-wrapping wavefront and the second spherical wavefront.

[0126] Example 12 is the method of Example 11 (or the method of any other previous or subsequent examples, alone or in combination), wherein the second predetermined phase height is not equal to 1 wave.

[0127] Example 13 is a method of Example 11 (or any other method of previous or subsequent examples, alone or in combination), wherein a first subsurface optical structure is configured to correct a first stage of a patient’s presbyopia, and wherein a second subsurface optical structure is configured to correct a second stage of a patient’s presbyopia, wherein the second stage of a patient’s presbyopia occurs after the first stage of a patient’s presbyopia.

[0128] Example 14 is an ophthalmic lens for correcting presbyopia in a patient. The ophthalmic lens of Example 14 includes a first subsurface optical structure comprising concentric Fresnel rings within the lens. Each of the concentric Fresnel rings may define a volume having a desired refractive index. The first subsurface optical structure is configured to: induce a first spherical aberration in the ophthalmic lens; and diffract light to multiple focal points based on a phase-wrapped wavefront having a first predetermined phase height not equal to one wave.

[0129] Example 15 is an ophthalmic lens of Example 14 (or an ophthalmic lens of any other previous or subsequent example, alone or in combination), wherein the ophthalmic lens is the patient's artificial lens, contact lens, or cornea.

[0130] Example 16 is an ophthalmic lens of Example 14 (or any other ophthalmic lens of the preceding or subsequent examples, alone or in combination), wherein a first subsurface optical structure is configured to make the ophthalmic lens a bifocal lens with an increased magnification of 2 diopters.

[0131] Example 17 is an ophthalmic lens of Example 14 (or an ophthalmic lens of any other previous or subsequent example, alone or in combination), wherein a first subsurface optical structure is configured to make the ophthalmic lens a bifocal lens with increased magnification of 1.5 diopters.

[0132] Example 18 is an ophthalmic lens of Example 14 (or any other ophthalmic lens of previous or subsequent examples, alone or in combination), wherein the first predetermined phase height is between about 0.5 and 0.6 waves.

[0133] Example 19 is an ophthalmic lens of Example 14 (or an ophthalmic lens of any other previous or subsequent example, alone or in combination), wherein the first spherical aberration is approximately -0.2 μm.

[0134] Example 20 is an ophthalmic lens of Example 14 (or an ophthalmic lens of any other previous or subsequent example, alone or in combination), wherein the first spherical aberration is approximately 0.2 μm.

[0135] Example 21 is an ophthalmic lens of any one of Examples 14 to 20 (or any other ophthalmic lens of any previous or subsequent examples, alone or in combination), wherein the ophthalmic lens further includes a second subsurface optical structure, wherein the first subsurface optical structure is embedded in a first layer of the ophthalmic lens, and the second subsurface optical structure is embedded in a second layer of the ophthalmic lens.

[0136] Example 22 is an ophthalmic lens of Example 21 (or any other ophthalmic lens of previous or subsequent examples, alone or in combination), wherein a first subsurface optical structure is configured to correct a first stage of a patient’s presbyopia, and wherein a second subsurface optical structure is configured to correct a second stage of a patient’s presbyopia, wherein the second stage of a patient’s presbyopia occurs after the first stage of a patient’s presbyopia.

[0137] Other variations are within the spirit of the invention. Thus, while the invention is readily adaptable to various modifications and alternative constructions, certain illustrated embodiments are shown in the accompanying drawings and have been described in detail above. However, it should be understood that this is not intended to limit the invention to the one or more specific forms disclosed, but rather to cover all modifications, alternative constructions, and equivalents falling within the spirit and scope of the invention, as defined in the appended claims.

[0138] In the context of describing the invention (especially in the context of the following claims), the terms “a,” “an,” and “the,” and similar designations are intended to be interpreted as covering both the singular and plural, unless otherwise stated herein or obviously contradicted by the context. The terms “comprising,” “having,” “including,” and “covering” should be interpreted as open-ended terms (i.e., meaning “including, but not limited to”), unless otherwise noted. The term “connected” should be interpreted as being partially or wholly included, attached to, or combined, even with some intermediaries. The recitation of value ranges herein is intended only as a shorthand method for individually referring to each individual value falling within that range, unless otherwise stated herein, and each individual value is incorporated into this specification as if it were separately recited herein. All methods described herein may be performed in any suitable order, unless otherwise stated herein or obviously contradicted by the context. The use of any and all examples or exemplary language (e.g., “such as”) provided herein is intended only to better illustrate embodiments of the invention and does not constitute a limitation on the scope of the invention, unless otherwise required. The language in this specification should not be construed as indicating that any unclaimed element is necessary for practicing the invention.

[0139] Preferred embodiments of the invention have been described herein, including the best modes known to the inventors for carrying out the invention. Variations of these preferred embodiments will become apparent to those skilled in the art upon reading the foregoing description. The inventors intend that those skilled in the art will use these variations as appropriate, and the inventors intend that the invention be practiced in forms other than those specifically described herein. Correspondingly, the invention includes all modifications and equivalents to the subject matter set forth in the appended claims, as permitted by applicable regulations. Furthermore, any combination of the foregoing elements in all possible variations is covered by the invention unless otherwise stated herein or clearly contradicted by the context.

[0140] All references cited in this document (including publications, patent applications and patents) are incorporated herein by reference as if each reference were individually and specifically indicated to be incorporated by reference and to be presented in its entirety in this document.

Claims

1. A method for modifying a non-native ophthalmic lens to improve image quality in a presbyopic patient, the method comprising: A change in the refractive index of the subsurface volume of the non-native ophthalmic lens is caused to form a first subsurface optical structure, the first subsurface optical structure being configured to induce a first wavefront correction, the first wavefront correction being configured to increase the patient's depth of focus and intermediate visual quality when the patient has a first accommodative range; and A change in the refractive index of the subsurface volume of the non-native ophthalmic lens is caused to form a second subsurface optical structure, wherein the first subsurface optical structure and the second subsurface optical structure are configured in combination to cause a second wavefront correction, which is configured to increase the patient's depth of focus and intermediate visual quality when the patient has a second accommodation range smaller than the first accommodation range.

2. The method as described in claim 1, characterized in that, The non-native ophthalmic lens is an artificial lens implanted in the patient.

3. The method as described in claim 1, characterized in that: The first wavefront correction provides a first bifocal correction, which has an increased magnification of a first diopter; and The first wavefront correction and the second wavefront correction together provide a second bifocal correction, the second bifocal correction having an increased magnification of a second diopter that is greater than the increased magnification of the first diopter.

4. The method as described in claim 3, characterized in that, The combination of the first and second wavefront corrections further induces spherical aberration.

5. The method as described in claim 4, characterized in that, The spherical aberration is approximately -0.2 μm.

6. The method as described in claim 4, characterized in that, The spherical aberration is approximately 0.2 μm.

7. The method as described in claim 1, characterized in that: The first wavefront correction provides a first trifocal correction, which has an increased magnification of the first trifocal point; and The first wavefront correction and the second wavefront correction together provide a second trifocal correction, the second trifocal correction having an increased magnification of the second trifocal point, the increased magnification of the second trifocal point being greater than the increased magnification of the first trifocal point.

8. The method as described in claim 7, characterized in that, The combination of the first and second wavefront corrections further induces spherical aberration.

9. The method as described in claim 8, characterized in that, The spherical aberration is approximately -0.2 μm.

10. The method as described in claim 8, characterized in that, The spherical aberration is approximately 0.2 μm.

11. The method as described in claim 7, characterized in that: The first wavefront correction further induces the first spherical aberration; and The combination of the first wavefront correction and the second wavefront correction further induces a second spherical aberration.

12. The method as described in claim 1, characterized in that: The first wavefront correction causes the first spherical aberration; and The first wavefront correction and the second wavefront correction together provide bifocal correction and cause a second spherical aberration.

13. The method as described in claim 1, characterized in that: The first wavefront correction causes the first spherical aberration; and The first wavefront correction and the second wavefront correction together provide trifocal correction and cause a second spherical aberration.

14. The method as described in claim 1, characterized in that, The first wavefront correction is configured to diffract light to multiple focal points based on a first phase-wrapped wavefront having a first predetermined phase height not equal to 1 wave.

15. The method as described in claim 14, characterized in that, The first predetermined phase height is between approximately 0.5 and 0.6 waves.

16. The method as described in claim 14, characterized in that, The second wavefront correction is configured to diffract light to multiple focal points based on a second phase-wrapped wavefront having a second predetermined phase height not equal to 1 wave.

17. The method as described in claim 16, characterized in that, The first predetermined phase height is between approximately 0.5 and 0.6 waves.

18. The method as described in claim 1, characterized in that, The change in refractive index that causes a change in the subsurface volume of the non-native ophthalmic lens to form the first subsurface optical structure and the second subsurface optical structure includes introducing an energy pulse into the non-native ophthalmic lens.

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