DIFFRACTIVE LENSES WITH DIFFRACTIVE ORDER SHIFT
20230255750 · 2023-08-17
Inventors
Cpc classification
G02C2202/22
PHYSICS
International classification
Abstract
Apparatuses, systems and methods for providing improved ophthalmic lenses, particularly intraocular lenses (IOLs). Embodiments may include a shift of a diffractive order.
Claims
1-15. (canceled)
16. An ophthalmic lens comprising: an optic including a diffractive profile formed by shifting a distance focus of the diffractive profile having a plurality of repeat periods from a first diffractive order to a second diffractive order by N diffractive orders by modifying the diffractive profile with a linear function that has a slope in r-squared space that reaches one wavelength multiplied by N at the end of each of the repeat periods.
17. The ophthalmic lens of claim 16, wherein the diffractive profile is defined by a first function that repeats in r-squared space for each of the repeat periods, and the linear function has been added to the first function in r-squared space.
18. The ophthalmic lens of claim 17, wherein the linear function repeats for each of the repeat periods.
19. The ophthalmic lens of claim 18, wherein the diffractive profile includes a plurality of parabolic optical zones or a plurality of non-parabolic optical zones.
20. The ophthalmic lens of claim 19, wherein the diffractive profile includes a plurality of optical zones and a plurality of transition zones between the plurality of optical zones, wherein the plurality of transition zones includes a periodic spacing or an aperiodic spacing.
21. The ophthalmic lens of claim 16, wherein the distance focus is shifted from the first diffractive order to the second diffractive order by one diffractive order or two diffractive orders.
22. The ophthalmic lens of claim 21, wherein the first diffractive order is the 0.sup.th diffractive order and the second diffractive order is the 1.sup.st diffractive order or the 2.sup.nd diffractive order.
23. The ophthalmic lens of claim 21, wherein the diffractive profile includes a plurality of optical zones, at least one of the plurality of optical zones having a height that is less than one wavelength.
24. The ophthalmic lens of claim 23, wherein the diffractive profile includes a set of at least two optical zones that repeats upon the optic in r-squared space.
25. The ophthalmic lens of claim 21, wherein at least one of the plurality of optical zones has a height that is greater than one wavelength.
26-70. (canceled)
71. The ophthalmic lens of claim 25, wherein the diffractive profile includes a set of at least two optical zones that repeats upon the optic in r-squared space.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0018]
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DETAILED DESCRIPTION
[0035]
[0036]
[0037] Each major face of lens 11, including the anterior (front) surface and posterior (back) surface, generally has a refractive profile, e.g. biconvex, plano-convex, plano-concave, meniscus, etc. The two surfaces together, in relation to the properties of the surrounding aqueous humor, cornea, and other optical components of the overall optical system, define the effects of the lens 11 on the imaging performance by eye E. Conventional, monofocal IOLs have a refractive power based on the refractive index of the material from which the lens is made, and also on the curvature or shape of the front and rear surfaces or faces of the lens. One or more support elements may be configured to secure the lens 11 to a patient's eye.
[0038] Multifocal lenses may optionally also make special use of the refractive properties of the lens. Such lenses generally include different powers in different regions of the lens so as to mitigate the effects of presbyopia. For example, as shown in
[0039] Rather than relying entirely on the refractive properties of the lens, multifocal diffractive IOLs or contact lenses can also have a diffractive power, as illustrated by the IOL 18 shown in
[0040] The diffractive profile of a diffractive multifocal lens directs incoming light into a number of diffractive orders. As light 13 enters from the front of the eye, the multifocal lens 18 directs light 13 to form a distance focus 15a on retina 16 for viewing distant objects and a near focus 15b for viewing objects close to the eye. Depending on the distance from the source of light 13, the focus on retina 16 may be the near focus 15b instead. Typically, distance focus 15a is associated with 0.sup.th diffractive order and near focus 15b is associated with the 1.sup.st diffractive order, although other orders may be used as well.
[0041] Bifocal ophthalmic lens 18 typically distributes the majority of light energy into two viewing orders, often with the goal of splitting imaging light energy about evenly (50%:50%), one viewing order corresponding to distance vision and one viewing order corresponding to near vision, although typically, some fraction goes to non-viewing orders.
[0042] Trifocal or quadrifocal ophthalmic lenses may be provided, which may have one or more intermediate foci. A trifocal ophthalmic lens may include an intermediate focus, which may provide for vision at an intermediate distance. A quadrifocal ophthalmic lens may include a first intermediate focus and a second intermediate focus, which may each provide for vision at respective intermediate distances. For example, the first intermediate focus may be between the distance focus and the second intermediate focus. The second intermediate focus may be between the first intermediate focus and the near focus. Other forms of ophthalmic lenses may be utilized in embodiments (e.g., a greater number of foci, such as a pentafocal lens).
[0043] Corrective optics may be provided by phakic IOLs, which can be used to treat patients while leaving the natural lens in place. Phakic IOLs may be angle supported, iris supported, or sulcus supported. The phakic IOL can be placed over the natural crystalline lens or piggy-backed over another IOL. It is also envisioned that the present disclosure may be applied to inlays, onlays, accommodating IOLs, pseudophakic IOLs, other forms of intraocular implants, spectacles, and even laser vision correction.
[0044]
[0045] When fitted onto the eye of a subject or patient, the optical axis of lens 20 is generally aligned with the optical axis of eye E. The curvature of lens 20 gives lens 20 an anterior refractive profile and a posterior refractive profile. Although a diffractive profile may also be imposed on either anterior surface 21 or posterior surface 22 or both,
[0046]
[0047] Diffractive profiles of ophthalmic lenses may have properties of chromatic correction that may reduce or fully compensate the positive chromatic aberration of the human cornea. Diffractive ophthalmic lenses may utilize the 0.sup.th and 1.sup.st diffractive order as the distance focus and near focus, respectively, of the ophthalmic lens. For the distance focus, the 0.sup.th diffractive order energy goes to the distance image formed by the refractive carrier lens, whereas the 1.sup.st diffractive order energy goes to the near image formed by the combination of the carrier lens plus the add power provided by the diffractive profile. In such a case, however, there may be a reduction or compensation (depending on the add power) of the chromatic aberration of the human cornea only at the near focus.
[0048] Embodiments herein may be directed, in part, to providing an ophthalmic lens in which a chromatic correction is provided at a distance focus of an ophthalmic lens. Embodiments herein may be directed, in part, to providing an ophthalmic lens in which a chromatic correction may be provided at a distance focus in addition to a near focus, and in embodiments, in addition to one or more intermediate foci. Embodiments herein may be directed, in part, to providing an ophthalmic lens in which a distance focus corresponds to a diffractive order that is not the 0.sup.th diffractive order. Such a configuration may allow for chromatic correction at a distance focus, as well as other foci (e.g., one or more of a near focus or one or more intermediate foci). Embodiments herein may be directed, in part, to shifting a distance focus of a diffractive profile from a first diffractive order to a second diffractive order by modifying the diffractive profile. In embodiments, the distance focus may be shifted from corresponding to a 0.sup.th diffractive order to a diffractive order that is not the 0.sup.th diffractive order.
[0049]
[0050] The diffractive profile 40 has a plurality of the repeat periods (ρ.sub.0). The diffractive profile 40 is shown to repeat in r-squared space for each of the repeat periods (ρ.sub.0). According to embodiments herein, the diffractive profile 40 may comprise a variety of different forms of diffractive profiles, including a plurality of parabolic optical zones or parabolic echelettes, or a plurality of non-parabolic optical zones or non-parabolic echelettes, or transition zones having a periodic spacing or an aperiodic spacing. According to embodiments herein, the diffractive profile 40 may comprise an arbitrary diffractive profile that may repeat in r-squared space. Methods disclosed herein may be applied to an arbitrary diffractive profile that may repeat in r-squared space.
[0051] An arbitrary diffractive profile (as represented by diffractive profile 40) that repeats in r-squared spaced for each of the repeat periods may be defined by a function as follows:
[0052] Where ƒ(ρ) is an arbitrary function defined on the range [0, ρ.sub.0] that constitutes one repeat of the diffractive profile for the repeat period (ρ.sub.0) (in r-squared space). Thus defined, the profile repeats the shape of ƒ every ρ.sub.0.
[0053]
[0054] According to embodiments herein, the diffractive profile may be modified with a function to shift one or more of the foci from a first (or initial) diffractive order to a second (or subsequent) diffractive order. The one or more foci may be shifted for a variety of purposes. For example, as discussed herein, chromatic correction may be limited with a distance focus corresponding to a 0.sup.th diffractive order. As such, it may be beneficial to shift the distance focus from the 0.sup.th diffractive order to a 1.sup.st diffractive order or a 2.sup.nd diffractive order, or another diffractive order to improve chromatic correction.
[0055] According to embodiments herein, a shift from a first diffractive order to a second diffractive order may occur for a variety of foci, and may be a single order shift or a multiple order shift. Various forms of diffractive order shifting may be provided as desired, for various foci. The methods disclosed herein may be applied to an arbitrary function that may repeat in r-squared space. The arbitrary function may comprise a variety of different forms of diffractive profiles, including a plurality of parabolic optical zones or echelettes, or a plurality of non-parabolic optical zones or echelettes, or transition zones having a periodic spacing or an aperiodic spacing.
[0056] According to embodiments herein, the diffractive order shifting may occur by modifying a diffractive profile with a linear function in r-squared space. The linear function in r-squared space may comprise a profile that may be defined as g(ρ) as follows:
[0057] The value N.sub.shift comprises the number (N) of diffractive orders that the diffractive profile is to be shifted by.
[0058] The diffractive profile 40 may be modified with the linear function g(ρ) by adding the linear function g(ρ) to the function ƒ(ρ) defining the diffractive profile 40 in r-squared space, with the new diffractive sag profile Δ.sub.shift being defined as follows:
Δ.sub.shift(ρ)=ƒ(ρ′)+g(ρ′) (Eq. 4)
The diffractive profile will be shifted by number (N) of diffractive orders that the diffractive profile is to be shifted by. A resulting diffractive profile 52 is shown in a solid line in
[0059]
[0060] According to embodiments herein, the shifts may occur for various foci of an ophthalmic lens, including shifting a distance focus of a diffractive profile for an optic of an ophthalmic lens from a first diffractive order to a second diffractive order by modifying the diffractive profile with a linear function in r-squared space. Shifting the distance focus may provide a variety of benefits, including but not limited to providing chromatic correction at a distance focus.
[0061] In embodiments, the amount of the shift may be by one diffractive order or may be by two diffractive orders (as represented in
[0062]
[0063]
[0064] The ophthalmic lens may include a plurality of optical zones or echelettes 66. The optical zones or echelettes 66 may each include an optical portion, and a transition zone (with exemplary optical portion marked as reference number 68, and exemplary transition zone marked as reference number 70). The echelettes 66 may include a set of echelettes that repeats in r-squared space upon the optic. For example, the set 72 may include three echelettes 74a, b, c. This set 72 may be repeated in r-squared space radially outward from the set 72 (e.g., set 76 is marked in
[0065] The echelettes 66 may comprise parabolic echelettes according to the methods of
[0066] Heights, or zone heights, (in units of wavelength) and the offsets, or zone offsets, (in units of wavelength) for the echelettes of the repeating set 72 may be provided in the table below:
TABLE-US-00001 TABLE 1 Echelette (by Height (in Offset (in reference number) wavelengths) wavelengths) 74a 0.6000 0 74b 0.4000 0 74c 0.2000 0
[0067]
[0068] As discussed herein, it may be beneficial to modify the diffractive profile such that the 0.sup.th diffractive profile does not correspond to the distance focus. The benefits may include providing chromatic correction at a distance focus.
[0069]
[0070]
Height′(i)=Height(i)+OrderShift/Period (Eq. 5)
Offset′(i)=Offset(i)−(i−1)*OrderShift/Period (Eq. 6)
[0071] The resulting values for the modified echelettes may be as follows:
TABLE-US-00002 TABLE 2 Echelette (by Height′ (in Offset′ (in reference number) wavelengths) wavelengths) 74a′ 0.9333 0 74b′ 0.7333 −1/3 74c′ 0.5333 −2/3
[0072] The modified echelettes 74a′, 74b′, 74c′ of the set 72 may repeat across the optic as shown in
[0073]
[0074] In embodiments, the diffractive profile may be shifted by two diffractive orders utilizing methods herein.
TABLE-US-00003 TABLE 3 Echelette (by Height″ (in Offset″ (in reference number) wavelengths) wavelengths) 74a″ 1.2667 0 74b″ 1.0667 −2/3 74c″ 0.8667 −4/3
[0075] The modified echelettes 74a″, 74b″, 74c″ of the set 72 may repeat across the optic as shown in
[0076]
[0077] Providing a distance focus at a 1.sup.st diffractive order or a 2.sup.nd diffractive order of the diffractive profile may have a variety of benefits, including chromatic correction at the distance focus. Further, chromatic correction may be provided at the near focus, and the first intermediate focus and the second intermediate focus. Shifting the distance focus to a 3.sup.rd diffractive order may produce undesirable results, and in embodiments, the shift may be no more than to the 2.sup.nd diffractive order (or two shifts of the diffractive orders). A shift of the distance focus to the 3.sup.rd diffractive order (or a shift of three orders) may compensate a chromatic aberration of a cornea for a distance focus, but it may overcorrect it for the remaining orders—possibly leaving it uncorrected with an opposite sign for near vision. This may result in reduced contrast modulation for intermediate and near vision. As such, in embodiments, the shift may be limited to a shift of two orders for a quadrifocal lens, or a shift being no greater than to the 2.sup.nd diffractive order for a distance focus. Providing a distance focus at a 1.sup.st diffractive order or a 2.sup.nd diffractive order may balance the effects of chromatic aberration throughout the different focusing distances. In embodiments, a greater shift may be provided as desired. For example, a shift may be at or greater than three orders for a quadrifocal, or may be at or greater than three orders for a pentafocal, among other results. In embodiments, any number of shifts may be provided for an optic having any number of foci according to methods herein.
[0078]
[0079] The set of two optical zones or echelettes may repeat at least twice upon the optic in r-squared space. The set may repeat at least twice upon the optic in r-squared space. A first echelette of the set of the two echelettes may have a first height and a second echelette of the set of two echelettes may have a second height that is different than the first height. A first echelette of the set of two echelettes may have a first offset, and a second echelette of the set of two echelettes may have a second offset that is different than the first offset.
[0080] For a trifocal lens, shifting the distance focus to a 2.sup.nd diffractive order may produce undesirable results, and in embodiments, the shift may be no more than to the 1.sup.st diffractive order (or one shift of the diffractive orders). A shift of the distance focus to the 2.sup.nd diffractive order (or a shift of two orders) may compensate a chromatic aberration of a cornea for a distance focus, but it may overcorrect it for the remaining orders—possibly leaving it uncorrected with an opposite sign for near vision. This may result in reduced contrast modulation for intermediate and near vision. As such, in embodiments, the shift may be limited to a shift of one order for a trifocal lens, or a shift being no greater than to the 1.sup.st diffractive order for a distance focus. Providing a distance focus at a 1.sup.st diffractive order may balance the effects of chromatic aberration throughout the different focusing distances. In embodiments, a greater shift may be provided as desired. For example, a shift of two orders, or three or more orders may be provided with a trifocal lens as desired.
[0081] The methods disclosed herein may be applied to other forms of optics and ophthalmic lenses as desired.
[0082] An optic for an ophthalmic lens that includes a profile disclosed herein may be fabricated utilizing a variety of methods. A method may include determining optical aberrations of a patient's eye. Measurements of a patient's eye may be made in a clinical setting, such as by an optometrist, ophthalmologist, or other medical or optical professional. The measurements may be made via manifest refraction, autorefraction, tomography, or a combination of these methods or other measurement methods. The optical aberrations of the patient's eye may be determined. Physical characteristics of the patient's eye may also be measured, such as pupil size and dilated and contracted sizes of the pupil may also be determined.
[0083] The measurements of the patient's eye may be placed in an ophthalmic lens prescription, which includes features of an optic that are intended to address the optical aberrations of the patient's eye, as well as features that address the pupillary size (including dilated and contracted sizes) of the patient.
[0084] The ophthalmic lens prescription may be utilized to fabricate an optic for the ophthalmic lens. A refractive profile of the optic, and a diffractive profile, among other properties may be determined based on the ophthalmic lens prescription.
[0085] The determination of a profile of the optic and the fabrication of the optic may be performed remotely from the optometrist, ophthalmologist, or other medical or optical professional that performed the measurements of a patient's eye, or may be performed in the same clinical facility of such an individual. If performed remotely, the fabricated optic may be delivered to an optometrist, ophthalmologist, or other medical or optical professional, for being provided to a patient. For an intraocular lens, the fabricated optic may be provided for implant into a patient's eye.
[0086] The fabricated optic may be a custom optic fabricated specifically for the patient's eye, or may be fabricated in a manufacturing assembly and then selected by an optometrist, ophthalmologist, or other medical or optical professional for supply to a patient, which may include implantation in the patient's eye.
[0087]
[0088] The processor 92 may comprise a central processing unit (CPU) or other form of processor. In certain embodiments the processor 92 may comprise one or more processors. The processor 92 may include one or more processors that are distributed in certain embodiments, for example, the processor 92 may be positioned remote from other components of the system 90 or may be utilized in a cloud computing environment. The memory 96 may comprise a memory that is readable by the processor 92. The memory 96 may store instructions, or features of intraocular lenses, or other parameters that may be utilized by the processor 92 to perform the methods disclosed herein. The memory 96 may comprise a hard disk, read-only memory (ROM), random access memory (RAM) or other form of non-transient medium for storing data. The input 94 may comprise a port, terminal, physical input device, or other form of input. The port or terminal may comprise a physical port or terminal or an electronic port or terminal. The port may comprise a wired or wireless communication device in certain embodiments. The physical input device may comprise a keyboard, touchscreen, keypad, pointer device, or other form of physical input device. The input 94 may be configured to provide an input to the processor 92.
[0089] The system 90 may be utilized to perform the methods disclosed herein, such as the processes of determining a profile of an optic.
[0090] The processor 92 may provide the profile of the optic to the manufacturing assembly 98, which may be configured to fabricate the optic for the ophthalmic lens based on the profile. The manufacturing assembly 98 may comprise one or more apparatuses for forming the optic and may comprise a high volume manufacturing assembly or a low volume manufacturing assembly. The manufacturing assembly 98 may be used for manufacture remote to a clinic in which measurements of the individual's eye or made, or local to such a clinic. The manufacturing assembly may include apparatuses such as lathe tools, or other lens formation devices to fabricate the optic.
[0091] In one embodiment, the processor 92 may be provided with an ophthalmic lens prescription for the individual's eye that may be provided as discussed herein. The processor 92 may receive the ophthalmic lens via the input 94. The system 90 may fabricate the optic for the ophthalmic lens based on the prescription.
[0092] The system 90 may be configured to fabricate any of the embodiments of ophthalmic lenses disclosed herein.
[0093] In embodiments, the methods disclosed herein may comprise methods performed with a processor 92. In embodiments, the method disclosed herein may be performed by a user. For example, methods of providing an optic of an ophthalmic lens may be performed by distributing, manufacturing, fabricating, designing, or otherwise providing such an optic of an ophthalmic lens. The optic may be configured according to embodiments herein and may be produced utilizing any of the methods disclosed herein.
[0094] Any of the embodiments of lens profiles discussed herein may be apodized to produce a desired result. The apodization may result in the heights and offsets of the echelettes being gradually varied according to the apodization, as to gradually increasing the amount of light in the distance focus as a function of pupil diameter.
[0095] The features of the optics disclosed herein may be utilized by themselves, or in combination with refractive profiles of the optics and/or with other features providing for correction of chromatic aberrations.
[0096] The ophthalmic lenses disclosed herein in the form of intraocular lenses are not limited to lenses for placement in the individual's capsular bag. For example, the intraocular lenses may comprise those positioned within the anterior chamber of the eye. In certain embodiments the intraocular lenses may comprise “piggy back” lenses or other forms of supplemental intraocular lenses.
[0097] Features of embodiments may be modified, substituted, excluded, or combined as desired.
[0098] In addition, the methods herein are not limited to the methods specifically described and may include methods of utilizing the systems and apparatuses disclosed herein.
[0099] In closing, it is to be understood that although aspects of the present specification are highlighted by referring to specific embodiments, one skilled in the art will readily appreciate that these disclosed embodiments are only illustrative of the principles of the subject matter disclosed herein. Therefore, it should be understood that the disclosed subject matter is in no way limited to a particular methodology, protocol, and/or reagent, etc., described herein. As such, various modifications or changes to or alternative configurations of the disclosed subject matter can be made in accordance with the teachings herein without departing from the spirit of the present specification. Lastly, the terminology used herein is for the purpose of describing particular embodiments only, and is not intended to limit the scope of systems, apparatuses, and methods as disclosed herein, which is defined solely by the claims. Accordingly, the systems, apparatuses, and methods are not limited to that precisely as shown and described.
[0100] Certain embodiments of systems, apparatuses, and methods are described herein, including the best mode known to the inventors for carrying out the same. Of course, variations on these described embodiments will become apparent to those of ordinary skill in the art upon reading the foregoing description. The inventor expects skilled artisans to employ such variations as appropriate, and the inventors intend for the systems, apparatuses, and methods to be practiced otherwise than specifically described herein. Accordingly, the systems, apparatuses, and methods include all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described embodiments in all possible variations thereof is encompassed by the systems, apparatuses, and methods unless otherwise indicated herein or otherwise clearly contradicted by context.
[0101] Groupings of alternative embodiments, elements, or steps of the systems, apparatuses, and methods are not to be construed as limitations. Each group member may be referred to and claimed individually or in any combination with other group members disclosed herein. It is anticipated that one or more members of a group may be included in, or deleted from, a group for reasons of convenience and/or patentability. When any such inclusion or deletion occurs, the specification is deemed to contain the group as modified thus fulfilling the written description of all Markush groups used in the appended claims.
[0102] The terms “a,” “an,” “the” and similar referents used in the context of describing the systems, apparatuses, and methods (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., “such as”) provided herein is intended merely to better illuminate the systems, apparatuses, and methods and does not pose a limitation on the scope of the systems, apparatuses, and methods otherwise claimed. No language in the present specification should be construed as indicating any non-claimed element essential to the practice of the systems, apparatuses, and methods.
[0103] All patents, patent publications, and other publications referenced and identified in the present specification are individually and expressly incorporated herein by reference in their entirety for the purpose of describing and disclosing, for example, the compositions and methodologies described in such publications that might be used in connection with the systems, apparatuses, and methods. These publications are provided solely for their disclosure prior to the filing date of the present application. Nothing in this regard should be construed as an admission that the inventors are not entitled to antedate such disclosure by virtue of prior invention or for any other reason. All statements as to the date or representation as to the contents of these documents is based on the information available to the applicants and does not constitute any admission as to the correctness of the dates or contents of these documents.