Accommodating intraocular lens with variable aberration combination for extended depth of field

Abstract

The invention relates to an accommodative intraocular lens having an optical axis (3), wherein the lens comprises at least two optical elements (1, 2), and haptics for allowing mutual translation of the elements (1, 2) in a direction substantially perpendicular to the optical axis (3), wherein at least two of the elements (1, 2) comprise free-form optical surfaces. The invention also relates to a combination of such a lens and a device adapted for measuring the optical power of an eye.

Description

Technical Field

[0001] An accommodative lens provides a combination of variable defocus and a desired variable depth of field, or alternatively, a lens provides a combination of variable defocus and variable correction of undesirable variable optical aberrations. Free-form optical curves for varying optical power can be provided preoperatively, during manufacture, or alternatively postoperatively by laser manipulation of an implanted lens. Background Art

[0002] This document, i.e., the present document, discloses a variant of an adjustable intraocular lens (hereinafter also referred to as a "lens") to be implanted in a human eye. A detailed description of such a lens and its variants is disclosed in, for example, NL2012133, NL201242, EP1871299, EP1932492 and many related documents to obtain the design of such an AIOL, and clinical results have been obtained, Alió described in Am J Ophthamol 2016Apr, 164: 37-48, but not limited to this, all documents and references listed herein should be considered as part of this document. This document discloses a variable focus lens, hereinafter referred to as a "lens". The lens has an optical axis and at least two optical elements, each of which includes at least one free optical surface, preferably, each optical element has at least one Alvarez cubic optical surface. Such a lens provides varying optical power, varying "defocus", wherein the degree of defocus depends on the degree of mutual movement of the optical elements in a direction substantially perpendicular to the optical axis. In addition, the variable focus lens also includes a wavefront coded phase mask "mask". The mask gradually changes the steepness of the free optical curve, changing the power of the cubic term, thereby providing an extended depth of field "EDOF". A cubic phase mask based on a constant cubic term, or alternatively, a modified cubic phase mask based on gradually changing, for example increasing, the cubic term is a preferred embodiment for the mask. Variable EDOF can also be achieved by alternative mask designs based on optical curves of combinations of other curves of other Zernike orders.

[0003] For example, at least two free optical surfaces for variable aspherical aberrations that provide variable flatness and spherical aberration can be added to a cubic surface that provides variable defocus, for example. To obtain the effect of spherical aberration on depth of field, refer to, for example, Mouroulis, "Depth of field extension with spherical optics", Optics Express, August 2008, Vol. 16, No. 17.

[0004] As described in, for example, EP2110702 and in the technical application of US6547139, it is well known that a cubic wavefront coded phase mask of EDOF can be used to extend the depth of field. The main invention of cubic phase coding is reported in ERDowski, Jr. and WT Cathey, "Extended depth of field through wavefront coding," Appl.Opt.34(11), 1859–1866 (1995), and in many accompanying patent documents, for example in US5748371 and WO9957599. The mask preferably modifies the phase of the light rather than the amplitude of the light. The mask can be a cubic mask that modifies the cubic term, or alternatively, it can be an aspheric mask that modifies the aspheric term, but is not limited to this, as long as the optical mask keeps the optical transfer function extended. This extension can be a fixed extension, or alternatively, as described in this document, it can be a variable extension, where the extension range depends on the displacement of the mask substantially perpendicular to the optical axis.

[0005] Note that EDOF extends the depth of focus, but by definition, EDOF also increases blur, thereby increasing the loss of contrast, especially for higher spatial frequencies. EDOF widens the "focus tunnel", i.e., the range of acceptable focus along the optical axis, which changes from "short and narrow" (i.e., sharp focus above short DOF) to "longer and wider", i.e., blurred focus above longer DOF. Whether the advantage of the degree of EDOF outweighs the disadvantage of loss of contrast depends primarily on the specific application requirements of the lens, which can be calculated and incorporated into the design of the mask. For example: humans require clear vision, high visual acuity vision for distance, e.g., >0.8 acuity; while near reading vision can drop to, e.g., 0.4 acuity. An accommodative intraocular lens that provides this "asymmetric EDOF" can be designed by methods such as those disclosed in this document.

[0006] The movement of optical elements for purposes such as accommodating intraocular lenses can be achieved by, but not limited to, the principles disclosed in US2009062912 and WO2005084587 and the same concept as various adaptations such as in US2014074233, WO2014058316, EP2765952, NL2012257278, US2010131955, US2010106245 and NL1029548. These principles have been shown to work well for camera applications, as well as for the human eye, for glasses and for accommodating intraocular lenses.

[0007] Such adjustable intraocular lenses can be used in ophthalmology, for example, for glasses and intraocular lenses implanted in human eyes. Such adjustable, translating intraocular lens structures and designs for such structures can be obtained from documents such as NL2012133, NL201242, EP1871299 and EP1932492; and corresponding clinical trial results can be obtained from, for example, the description of Alió et al. in Am J Ophthamol 2016Apr,164:37-48. Summary of the invention

[0008] This document discloses a lens that provides a combination of variable defocus and a desired variable depth of field, or a combination of variable defocus and variable correction of undesirable variable optical aberrations.

[0009] The lens has an optical axis and comprises at least two optical elements, wherein at least one element translates in at least one direction substantially perpendicular to the optical axis. Each optical element comprises at least one free optical surface, wherein the combination of these surfaces provides a change in at least one optical aberration of the lens, wherein the degree of change depends on the degree of displacement of at least one of the optical elements. Such translating lenses are known from the references, wherein these lenses typically, but not necessarily, comprise cubic optical surfaces to provide variable defocus power. Such cubic surfaces, additional optical surfaces and combinations of surfaces can be defined by Zernike polynomials, wherein the first fifteen modes are considered to be relevant to the human eye, and these polynomials are mentioned in this document to illustrate the free shapes of various optical surface shapes. Note that such optical shapes, such free rotationally asymmetric optical surfaces can also be derived from, for example: splines or Cartesian or NURBS algorithms or any other algorithm. Free surfaces derived from any formula or algorithm are considered to be included in this document. An embodiment of such a cubic surface is a surface defined according to the following formula:

[0010] t 1 =A(xy 2 +1 / 3x 3 )+E.

[0011] Firstly, the optical system of such a lens accommodates the eye by providing a variable focus, i.e. a variable defocus, to correct the defocus aberrations of the eye from far to near, assuming clear vision to reading distance. The translation of at least one optical element is a displacement of the element in a direction perpendicular to the optical axis, i.e. a slide, or alternatively, a rotation in a plane perpendicular to the optical axis, or alternatively, a wedging of the optical element, or alternatively, any combination of any movements in a plane substantially perpendicular to the optical axis.

[0012] The lens can include at least one anchoring haptic, i.e., a mechanical component for providing positioning and anchoring of an optical element in the anterior chamber or posterior chamber of the eye. The lens can include at least one translation haptic, i.e., a mechanical component that provides translation of at least one optical element by transmitting movement of at least one component in the eye to at least one optical element. The lens can include at least one haptic for providing a combination of positioning and translation. The lens can include at least one haptic that can couple with a natural part of the eye, which can be the ciliary mass of the eye, or alternatively, the zonular web of the eye, or alternatively, the capsular bag of the eye, or alternatively, the iris of the eye, or alternatively, any natural part of the eye. Additionally, the lens can be driven by fluid pressure generated in the posterior chamber of the eye, or alternatively, the lens can be driven by a MEMS, i.e., a micro-electromechanical system, that provides translation of at least one optical element. Furthermore, the lens may also include at least one optical curve for correcting any fixed optical condition of the eye, such as the fixed optical condition presbyopia, also known as reading hyperopia. Additionally, the lens is capable of providing correction of at least one undesirable variable optical condition of the eye, such as variable astigmatism or alternatively variable spherical aberration, which undesirable aberrations may be produced by any optical curve of the eye or, alternatively, by any optical curve of the lens.

[0013] The lens can provide a combination of variable defocus to increase depth of field at near vision. Alternatively, the lens can provide a combination of variable defocus and variable spherical aberration or variable astigmatism to correct variable and undesirable such aberrations of the eye. For example, the human eye is known to produce variable spherical aberration during natural accommodation. The cornea of ​​the eye has been shown to provide positive aspheric aberration that can change to negative spherical aberration during accommodation. Lenses according to the lens design described in this document may provide increased positive aspheric aberration, Zernike mode The asphericity depends on the degree of mutual translation of the optical elements. So far, vision is hardly affected and near vision reading is supported. Variable correction by additional free optical surfaces of the lens can modify the total aspheric aberration of the eye in any desired direction and according to the desired optical aspheric power. This variable correction can be rotationally symmetric or, alternatively, can be a more complex rotationally asymmetric design.

[0014] Variable coma, Zernike mode Can for example be caused by a tilt of the lens to the optical axis in the eye, the main effect of which is due to the tilt of the optical axis of the lens relative to the optical axis of the cornea. The tilt of an accommodative intraocular lens can be for example a coma power change due to a change in the tilt of the lens during the accommodative procedure. Such a variable coma can for example be corrected by an OCT device by for example measuring the tilt, then calculating the expected coma for post-operative evaluation, and subsequently by additional optical freeform surfaces that provide variable degrees of correction of for example the maximum recorded coma on or in the lens by post-operative modification of the intraocular material by laser processing. Variable astigmatism, Zernike mode The variable coma can be evaluated postoperatively, for example, by an OCT device by measuring the tilt and then calculating the expected degree of coma, and subsequently corrected by additional optical freeform surfaces that provide variable degrees of correction for, for example, the maximum recorded coma on or in the lens by postoperative modification of the intraocular material by laser processing.

[0015] Note, of course, that all variable aberrations can also be evaluated preoperatively and corrections added to the lens during custom manufacturing.

[0016] Optical surfaces for providing additional variable optical power can be added to the lens prior to implantation, during the manufacture of the lens, wherein the degree of variable optical power is based on preoperative measurements of the eye in which the lens is implanted. Alternatively, optical surfaces for providing additional variable optical power can be added to the lens after implantation, wherein the degree of variable optical power is based on postoperative measurements of the eye in which the lens is implanted, and at the same time, the intraocular material is modified postoperatively by, for example, laser treatment, such as: customized wavefront-guided refractive laser treatment of an adjustable intraocular lens after surgery as disclosed in WO2018152407. Such treatment can modify any at least one of the optical surfaces for variable aberration disclosed in this document. Such treatment can also modify optical surfaces that provide variable defocus, for example, by increasing the steepness of these surfaces to increase the diopter change per unit of mutual translation of the optical surfaces.

[0017] Preferably, the additional freeform surface is adapted to provide a variable increase in add power depending on the rate of mutual translation of the elements.

[0018] In an attractive embodiment, the additional freeform surface is adapted to provide a variable reduction in the add power depending on the rate of mutual translation of the elements.

[0019] Preferably, the additional freeform surface is adapted to provide a variable variation of the add power to provide an extension of the depth of field of the lens.

[0020] Another attractive embodiment provides the feature that the additional freeform surface is adapted to provide a variable variation of the additional optical power to reduce the depth of field of the lens.

[0021] It is also possible that the additional free-form surface is adapted to be able to provide a variable optical power of astigmatism.

[0022] Preferably, the additional free-form surface is adapted to provide an aspherical variable optical power.

[0023] According to another possibility, the additional freeform surface is adapted to be able to provide any variable focus degree of any Zernike mode.

[0024] It is also possible that the additional freeform surfaces are adapted to provide a combination of multiple variable optical powers of any multiple Zernike modes.

[0025] The invention also provides a lens according to any one of claims 1 to 9, and a combination of a device adapted to measure the optical power of the eye to be provided by the intraocular lens, and adapted to convert the measured optical power into the optical power of the intraocular lens.

[0026] Preferably, the device is adapted to: take measurements of an eye to be implanted with a lens, including providing measurements of the range of power variation of at least one variable aberration; and convert said power variation into a refractive power variation based on the same aberration provided by at least two free optical surfaces of the lens.

[0027] It is also possible that the device is adapted to: perform measurements on an eye implanted with a lens, including providing measurements of the range of diopter changes of at least one additional variable aberration; and convert said power changes into diopter changes based on the same aberration provided by at least two free optical surfaces of the lens; and perform adaptation of said diopter changes of the free surfaces by any post-operative free change procedure.

[0028] According to one embodiment, the device is adapted to manufacture the lens before implantation takes place.

[0029] However, it is also possible that the device is adapted to perform a postoperative free change procedure.

[0030] More specifically, the device is adapted to perform a post-operative free-change procedure by laser treatment of the lens in situ. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1-3 An example of variable extension of the depth of field of an accommodative lens including an additional freeform surface for variable aspheric aberration is shown. Figure 1-2 The diagram is used for illustration Figure 3The prior art of the present invention shown in .

[0032] Figure 1 .A non-aberrated, assumed perfect optical system with sharp focus in a desired range, wherein an accommodative lens comprises: two optical elements 1, 2 translated in a direction substantially perpendicular to an optical axis 3, an incident light beam 4, an optical axis 5, an outgoing focused light beam 6, a focus 7 providing near vision, and, after translation of at least one of the optical elements, a far focus 9 and a focal length 10 provided by the outgoing focused light beam 8 for the lens.

[0033] Figure 2 Aberration-fixed optical system with fixed blur focus, having a blurred focus 11, adds extended depth of field at near 13a where it may be desired, but also adds blur to far 13b, which is generally undesirable because far vision is more sensitive to image degradation than near vision. This figure shows, for example, the effect of adding a fixed focus aspheric lens to a fixed focus lens, illustrating the blur by a widened focus, focus tunnel 12, within the desired range.

[0034] Figure 3 This figure shows an embodiment of the invention. A variable aberration optical system with variable blur focus, for example, achieved by adding a variable aspheric surface to a variable focus lens, firstly produces blur 16, thereby extending the desired range 13a at near vision, and secondly, by variable correction of the blur, gradually reduces the focus tunnel to a sharp focus 15 for distance vision, while maintaining the same as in Figure 2 The extended focus range is shown in FIG. 17 . DETAILED DESCRIPTION

[0035] So, in summary, the present document discloses an accommodative intraocular lens having an optical axis, wherein the lens comprises at least two optical elements, wherein at least one element is adapted to translate in at least one direction substantially perpendicular to the optical axis, and at least two of these elements each comprise at least one free optical surface adapted to provide variable defocus optical power, wherein the degree of change in optical power depends on the degree of mutual displacement of the elements, wherein each element further comprises at least one additional free optical surface adapted to provide variable optical power for at least one additional aberration other than defocus, wherein the degree of variable additional aberration optical power depends on the degree of mutual displacement of the elements.

[0036] The additional free-form surface provides a variable increase of the additional variable optical power, depending on the degree of mutual displacement of the elements, or, alternatively, the additional free-form surface provides a variable decrease of the additional variable optical power, depending on the degree of mutual displacement of the elements.

[0037] For example, the additional freeform surface can provide variable variation of the additional variable optical power to provide an extension of the depth of field of the lens, or, alternatively, the additional freeform surface can provide variable variation of the additional variable optical power to provide a reduction of the depth of field of the lens.

[0038] The additional freeform surface can provide astigmatic variable optical power, or, alternatively, can provide aspheric variable optical power, or, alternatively, can provide any variable optical power of any Zernike mode, or, alternatively, can provide a combination of multiple variable optical powers of any multiple Zernike modes.

[0039] The method for providing such a lens may be a preoperative method comprising, firstly, measuring the eye to be implanted with the lens, comprising providing the measurement of the range of diopter changes of at least one variable aberration; secondly, converting said power change into a diopter change according to the same aberration provided by at least two free optical surfaces of the lens; and thirdly, providing for the manufacture and implantation of the lens. Alternatively, the method for providing such a lens may be a postoperative method comprising, firstly, measuring the eye to be implanted with the lens, comprising providing the measurement of the range of diopter changes of at least one additional variable aberration; secondly, converting said power change into a diopter change according to the same aberration provided by at least two free optical surfaces of the lens; and thirdly, providing for the adaptation of said diopter change of the free surfaces by any postoperative free modification procedure. The postoperative free modification procedure may be any procedure, for example, postoperative modification of intraocular materials by laser treatment, for example, femtosecond laser treatment.

[0040] Methods for providing such lenses can increase the diopter change of any aberration per unit translation of the optical element, such as, but not limited to, increasing aspheric aberrations to provide Figure 1-3 The desired depth of field extension is shown in .

[0041] Alternatively, methods for providing such a lens can reduce the diopter change per unit translation of the optical element of any aberration, such as a reduction in variable coma or any other variable that would undesirably degrade the visual acuity of the eye.

[0042] The invention also relates to a combination of a lens according to the invention adapted for measuring the optical power of the eye provided by an intraocular lens and a device adapted for converting the measured optical power into the optical power of the intraocular lens.

[0043] In one embodiment, the device is adapted to: be used to measure an eye implanted with a lens, including providing measurement results of the range of optical focal changes of at least one variable aberration; and convert the optical focal change into a refractive power change based on the same aberration provided by at least two free optical surfaces of the lens.

[0044] In one embodiment (which may be combined with other embodiments of the invention), the device is adapted to: perform measurements on an eye implanted with a lens, including measurements of the range of refractive power changes providing at least one additional variable aberration; and convert said power changes into refractive power changes based on the same aberration provided by at least two free optical surfaces of the lens; and perform adaptation of said refractive power changes of the free surfaces through any post-operative free change procedure.

[0045] In one embodiment (which may be combined with other embodiments of the invention), the apparatus is adapted to manufacture a lens.

[0046] In one embodiment (which may be combined with other embodiments of the invention), the device is adapted to perform a post-operative free change procedure.

[0047] In one embodiment (which may be combined with other embodiments of the invention), the device is adapted to perform a post-operative free-change procedure by laser treatment of the lens in situ.

Claims

1. An accommodative intraocular lens having an optical axis, wherein: The lens comprises at least two optical elements, and haptics for allowing the at least two optical elements to translate relative to each other in a direction substantially perpendicular to the optical axis, wherein each of the at least two optical elements comprises at least one first freeform optical surface adapted to provide a variable increase or decrease in defocus power depending on the extent to which the elements are translated relative to each other to correct for defocus aberrations of the eye, and It is characterized in that each of the at least two optical elements includes at least one second free optical surface, which is capable of providing a variable increase or decrease in the optical focal length of at least one additional aberration other than defocus, and the variable increase or decrease in the optical focal length of the additional aberration depends on the degree of mutual translation of the at least two elements; wherein the at least one second free optical surface is adapted to provide a variable extension of the depth of field of the lens by providing a variable change in the additional optical focal length.

2. The lens according to claim 1, characterized in that The at least one second freeform surface is adapted to increase the depth of field of the lens by providing a variable variation of the add power.

3. The lens according to claim 1, characterized in that The at least one second freeform surface is adapted to reduce the depth of field of the lens by providing a variable variation of the add power.

4. The lens according to claim 1, characterized in that The at least one second freeform surface is adapted to provide variable astigmatism and variable optical power.

5. The lens according to claim 1, characterized in that The at least one second free-form surface is adapted to provide a variable aspheric variable optical power.

6. The lens according to claim 1, characterized in that The at least one second freeform surface is adapted to provide any variable focus power of any Zernike mode.

7. The lens according to claim 1, characterized in that The at least one second freeform surface is adapted to provide a combination of a plurality of variable optical powers of any plurality of Zernike modes.

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