Reducing the progression of myopia by means of an adapted active region

Abstract

The invention relates to the improvement of the balance between the effectiveness and compatibility of spectacle lenses while reducing the progression of myopia. For this purpose, the invention proposes a method in particular for calculating or optimizing a spectacle lens (10) for at least one eye of a spectacle wearer such that the spectacle lens (10) comprises: - a central main viewing region (30) with a substantially constant refractive power; and - an active region (32) which adjoins the central main viewing region and which produces -- an at least partly greater refractive power than the refractive power in the central main viewing region (30) and / or -- a contrast reduction at least in some sections, wherein the method has the steps of: - providing user data which comprises at least one spherical equivalent of a refraction deficit of the at least one eye; - determining a primary refractive power as the substantially constant refractive power of the central main viewing region in order to correct the spherical equivalent of the refraction deficit of the at least one eye; and - ascertaining a horizontal (rh) and / or a vertical extension (rv) of the central main viewing region (30) as a function of the primary refractive power.

Description

[0001] Reduction of myopia progression with adjusted field of action

[0002] Description

[0003] The invention relates to improving the balance between effectiveness and tolerability of spectacle lenses in reducing the progression of myopia.

[0004] Myopia management refers to the attempt to control abnormal longitudinal growth of the eye in children and adolescents, which leads to severe myopia and is caused, among other things, by a modern lifestyle (little time outdoors and a lot of close work). One possible approach to controlling the progression of myopia is wearing special lenses that attempt to pull the focal plane of the visual field in the periphery in front of the retina, thus slowing the longitudinal growth of the eye.

[0005] One possibility is spectacle lenses with a design similar to progressive lenses, which bring the focal plane in the peripheral field of vision in front of the retina through an additional power. (e.g. US 7,025,460, EP 1 934 648 B1 , WO 2017 / 222421 A1 , DE 10 2009 053 467 B4 ). Other variants of spectacle lenses have a multitude of small additional power areas (lenslets, etc.) distributed across the spectacle lens and creating a second focal plane in front of the retina. (e.g. CN 104678572 B, US 10268050 B2, WO 2019 / 166653 A1 , US 8950860 B2, US 10901237 B2, US 11061255 B2). Another possibility is the introduction of small scatterers that reduce the contrast in the periphery and thus inhibit the progression of myopia (e.g. WO 2018026697 A1 ).

[0006] What all these lenses have in common is that they have a central zone that provides good vision due to a prescription with a corresponding corrective power, and a peripheral zone that does not provide good vision due to myopia management measures (lenslets, power increase, or diffusers). The size of the central zone is crucial for the tolerability of the glasses, while the size of the peripheral power zone is crucial for the success of myopia management. The relationship between the two zones is usually determined by the lens design and is the same for all corrective powers. Suggestions for adapting the zones to the individual eye are described, for example, in EP 3 966 626 A1. These are based on additional measurements, either as peripheral refraction or using a psychophysical procedure.

[0007] Especially with lenses for correcting myopia, the often noticeable tendency for myopia to progress leads to a reduction in the wearing comfort of once fitted lenses and thus also in the wearer's satisfaction and the tolerability of the glasses after a short time.

[0008] To date, various optical effects regarding the tolerability and comfort of ophthalmic lenses, especially spectacle lenses, have been investigated with regard to their influence on myopia and / or hyperopia, as well as their progression or development, depending on the optical and physiological mechanisms that are intended to explain or slow down such progression or advancement, particularly worsening. Existing approaches are essentially based on projecting the image in front of the retina, as this is intended to slow the longitudinal growth of the eye. It has been shown that it is sufficient (or even better) if this occurs only in the periphery of the retina.

[0009] One object of the present invention is to improve the lasting compatibility of spectacles or a spectacle lens and thus to achieve long-term wearing comfort at low cost. This object is achieved according to the invention by the subject matter of the independent claims. Preferred embodiments are the subject matter of the dependent claims. Thus, in one aspect, the invention relates to a method, in particular a computer-implemented method, for calculating or optimizing a spectacle lens for at least one eye of a spectacle wearer such that the spectacle lens comprises a central main viewing area with a substantially constant refractive power (hereinafter also referred to as the primary refractive power) and an effective area adjacent to the central main viewing area.The primary refractive power in the central main visual area should be regarded as substantially constant, in particular in that the variations in the refractive power within the central main visual area are in a range of not more than about 1 dpt, preferably not more than about 0.5 dpt, most preferably not more than about 0.25 dpt.

[0010] The effective range of the spectacle lens to be calculated or optimized results in at least a partially higher refractive power (hereinafter also referred to as secondary refractive power) than the refractive power in the central main visual area and / or at least a partially reduced contrast (compared to the central main visual area).

[0011] Particularly in the case of a power range with increased refractive power (compared to the central main visual range), the central main visual range could preferably be considered to be a convex surface (in particular an elliptical surface, preferably a circular surface) with maximum surface area and / or with maximum horizontal and / or vertical extent, at the edge of which the refractive power of the spectacle lens does not exceed a certain limit value. In particular, this limit value could be a refractive power that is greater by a predetermined primary tolerance value than a minimum value or an average value of the refractive power within the central main visual range. Such a primary tolerance value is preferably not greater than approximately 1 dpt, particularly preferably not greater than approximately 0.5 dpt, most preferably not greater than approximately 0.25 dpt.

[0012] The increase in refractive power in the effective area (compared to the central main field of view) could, for example, be achieved by a continuous increase in the surface refractive power (similar to a PAL) and / or by refractive microstructures (e.g. lenslets) and / or by diffractive structures.

[0013] To achieve contrast reduction in the power zone, the lens could, for example, have surface roughness in the power zone, causing the optical image through the lens to become dull. This dullness could then lead to contrast reduction. The central main visual area could remain essentially clear, while the contrast reduction is only created in the power zone. This contrast reduction contributes to the fact that the central peripheral visual area provides little or no incentive for the eye to grow in length.

[0014] Particularly in the case of an effective area with a contrast reduction (compared to the main field of vision), the main field of vision could preferably be considered to be a convex surface (in particular an elliptical surface, preferably a circular surface) with maximum surface area and / or with maximum horizontal and / or vertical extent, at the edge of which the contrast of the image produced by the spectacle lens does not fall below a certain limit value. In particular, this limit value could be such that the perception (or a degree of perception) produced thereby lies in the range of at least approximately 0.5, preferably at least approximately 0.7, even more preferably at least approximately 0.8, most preferably at least approximately 0.9.

[0015] Perception should be understood here in particular as the factor by which the visual acuity (i.e. visual acuity) is reduced, whereby in particular a visual acuity determined to the value 1 in accordance with DIN 58220 Part 3 is assumed as the reference. Thus, a perception of 0 (<0.1) means essentially complete occlusion and 1 in principle means complete transparency. These properties arise in particular when the spectacle lens is arranged in a position with a typical corneal vertex distance (HSA), i.e. in particular with at least one value of the HSA in the range from approximately 11 mm to approximately 18 mm, particularly preferably with at least one value of the HSA of approximately 13 mm or approximately 14 mm.

[0016] Alternatively or in addition to adhering to the value ranges for perception proposed here, it may be particularly preferred if the contrast reduction caused by the microstructure in the effective area leads to a haze value (in particular % haze) according to the ASTM D-1003 standard in the range of not more than about 10, preferably in the range of not more than about 2, and wherein preferably the contrast reduction caused by the microstructure in the effective area leads to a haze value according to the ASTM D-1003 standard in the range of at least about 0.1, in particular at least about 0.5.

[0017] Particularly preferably, in the event of contrast reduction, the effective area still has a transmission (in particular a luminous transmittance value according to the ASTM D-1003 standard) of at least 85, even more preferably at least 90. This ensures that even in the event of contrast reduction, the spectacle lens does not completely block the light (e.g., absorb and / or reflect) and thus darken the field of vision, but rather that the light is only (partially) scattered. This largely preserves the impression of brightness and prevents the pupil from noticeably enlarging (due to reduced light incidence).

[0018] The values ​​for both haze and luminous transmittance according to the ASTM D-1003 standard can be determined or checked using the “haze-gard plus” measuring device from BYK Additives and Instruments, for example.

[0019] The method according to the invention comprises providing user data comprising at least one spherical equivalent of a refractive error of at least one eye. The spherical equivalent of the refractive error refers to the spherical component of the visual impairment, in particular myopia. In particular, the spherical equivalent of the refractive error of the central (or foveal) field of vision is provided. Providing user data can, in particular, comprise directly determining or measuring and / or providing previously measured and then, in particular, stored information. Providing can, in particular, comprise entering or transmitting the user data by means of a user interface and / or a data interface of a data processing system.

[0020] The method also comprises determining the primary refractive power as the substantially constant refractive power of the central main visual area for correcting the spherical equivalent of the refractive deficit of the at least one eye and determining a horizontal and / or a vertical extent of the central main visual area based on (or as a function of) the primary refractive power.

[0021] The horizontal and / or vertical extent of the central main field of vision is determined, in particular, based on (or as a function of) the primary refractive power, by determining the horizontal or vertical extent depending on the (pre-)determined value of the primary refractive power, in particular using a pre-defined rule or assignment, namely, in particular, calculating or reading it. Such a rule or assignment can, in particular, be a functional relationship, e.g., in the form of an (analytical) formula, between the primary refractive power and the horizontal or vertical extent.

[0022] In a further preferred embodiment, a table (e.g. assignment or reference table) with predefined values ​​or value ranges can serve as such a rule or assignment, which assigns a corresponding value for the horizontal or vertical extent of the central main visual area to each value of a primary refractive power. The use of such a table can be particularly advantageous when, in the course of determining the horizontal and / or vertical extent of the central main visual area, a spectacle lens (or spectacle lens blank) is selected from a series of spectacle lenses (or spectacle lens blanks). In this case, intervals of a primary refractive power (e.g. 1.5 - 2 dpt) can be assigned to a specific value of the horizontal or vertical extent of the main visual area. In a preferred aspect, the value used for determining the horizontal orThe (functional) relationship used for the vertical extension of the central main visual area should be such that the determined extension of the central main visual area results in a predetermined dimension (e.g., angular extension) of the field of vision. Preferably, the predetermined dimension (e.g., angular extension) of the field of vision can be substantially constant within a spectacle lens series.

[0023] The (predetermined) relationship (e.g. formula, table, etc.) between the primary refractive power and the horizontal and / or vertical extent of the central main visual field can also depend on one or more other parameters, e.g. in addition to the refractive power, also on the distance between the lens and the eye and / or on the position or distance of the eye pivot point from the lens, etc.

[0024] The present invention therefore proposes, in particular, to calculate or optimize the size of the central main field of vision and / or the field of effect depending on the distortion of the field of vision and thus achieves for each effect a tracked and thus at least improved balance between tolerability and effectiveness of the spectacle lens in suppressing the progression of myopia.

[0025] Within the scope of the present invention, it was particularly recognized that, strictly speaking, it is not (solely) the size of the central zone that is decisive for the (long-term) compatibility of the spectacle lens, but (not insignificantly also) the size of the field of vision to which this central zone of the spectacle lens corresponds. The size of the field of vision depends not only on the central zone but also on the angular distortion of the spectacle lens. This is determined, among other things, by the effect of the spectacle lens and, in particular, by the distance of the spectacle lens from the center of rotation of the eye. In a particularly preferred embodiment, the intrinsic magnification of the spectacle lens is also determined, and the horizontal and / or vertical extent of the central main field of vision is determined taking the intrinsic magnification into account.

[0026] Preferably, the horizontal and / or vertical extent of the central main visual area is determined as a (at least partially) monotonically increasing function of the primary refractive power of the spectacle lens. In the context of this development, it was particularly recognized that this can very effectively counteract an effect which conventionally leads to the size of the field of view of the central zone (especially for foveal vision) changing due to dynamic distortion when the corrective effect (especially the primary refractive power) changes, with the same physical size on the spectacle lens, in such a way that an optimum balance between effectiveness in suppressing myopia progression and tolerability of the spectacle lens is often not reliably achieved. For example, for minus lenses for the correction of myopia, it can be seen that with the same central zone (i.e.with the same central main field of vision) of the spectacle lens, the size of the central field of vision increases with higher myopia. This results in temporarily improved tolerability of the spectacle lens, with the same effectiveness for myopia management, i.e. the tolerability and effectiveness for myopia management are no longer in the desired balance. This can therefore, at least in the medium or long term, lead to a greater progression of myopia compared to a spectacle lens with an optimal balance between tolerability and effectiveness and thus to a decreasing tolerability or decreasing wearing comfort for the spectacle lens. This can be very effectively prevented or at least suppressed or delayed by a procedure according to the invention, in particular in the preferred embodiments described here.

[0027] Preferably, the provided user data also comprise a distance measure which defines or describes the distance b' of the spectacle lens to be calculated or optimized from the eye rotation point of the at least one eye (directly or indirectly), wherein preferably the horizontal and / or vertical extent of the central main field of vision is / are determined based on (or as a function of) the primary refractive power and the distance measure.

[0028] The distance measurement can be provided as an individual or standardized value. It can either directly specify an individual or standardized distance of the lens from the eye's center of rotation, or it can, for example, simply specify an individual or standardized corneal vertex distance (CVD), which then, together with an individual or standardized eye radius, describes the distance b' of the lens from the eye's center of rotation. For example, a standardized value for the eye radius could be provided or used together with an individual value for the CVD to describe an individual distance of the lens from the eye's center of rotation.This could be particularly advantageous given that individual variations in the HSA may be significantly greater than individual variations in the eye radius due to individual variations in head and eye anatomy, as well as due to the dependence on the selected spectacle frame and wearing habits. On the other hand, an individual HSA for a selected spectacle frame can be determined quite reliably using simple means.

[0029] In a particularly preferred embodiment, the horizontal and / or vertical extent of the central main field of vision is determined for a negative value of the primary refractive power as a (at least partially) monotonically decreasing function of the distance b' of the spectacle lens from the eye rotation point and for a positive value of the primary refractive power as a (at least partially) monotonically increasing function of the distance b' of the spectacle lens from the eye rotation point.Alternatively or additionally, the horizontal and / or vertical extent of the central main visual area is preferably determined for a negative value of the primary refractive power as a (at least partially) monotonically increasing function of the product of the distance b' of the spectacle lens from the eye pivot point and the primary refractive power, and for a positive value of the primary refractive power as a (at least partially) monotonically increasing function of the product of the distance b' of the spectacle lens from the eye pivot point and the primary refractive power. Particularly preferably, the horizontal extent r'h and / or the vertical extent r'v of the central main visual area is / are determined for negative values ​​of the primary refractive power according to rh / (1 - So b' F) < r'h < rh or according to r. v Z (1 - So b' F) < r'v < r v and / or for positive values ​​of the primary refractive power according to rh < r'h < rh / (1 - So b' F) or according to

[0030] Tv < r'v < Tv / (1 - So b' F) as a function of the primary refractive power F and the distance b' of the lens from the eye rotation point with a given reference value m for the horizontal extension or a given reference value r v for the vertical extent of the central main viewing area and a given positive upper weighting factor s0.

[0031] Further preferred is / are the horizontal extent r'h and / or the vertical extent r'v of the central main field of vision for negative values ​​of the primary refractive power according to rh / (1 - So b' F) < r'h < rh / (1 - s u b' F) or according to r v / (1 - So b' F) < r'v < r v / (1 - s u b' F) and / or for positive values ​​of the primary refractive power according to rh / (1 - Su b' F) < r'h < rh / (1 - So b' F) or according to r v / (1 — Su b' F) < r'v < r v / (1 - So b' F) as a function of the primary refractive power F and the distance b' of the lens from the eye rotation point with a given reference value m for the horizontal extension or a given reference value r v for the vertical extent of the central main viewing area as well as a predetermined positive upper weighting factor s0 and a predetermined positive lower weighting factor Su, which is not greater (but preferably smaller) than the upper weighting factor.

[0032] Preferably, the upper weighting factor is in a range of not greater than about 1.5, preferably not greater than about 1.2, most preferably not greater than about 1.0 and / or in a range of at least about 0.3, preferably at least about 0.5, even more preferably at least about 0.8, most preferably at least about 1.0. Alternatively or additionally, the lower weighting factor is preferably in a range of at least about 0.1, preferably at least about 0.3, more preferably at least about 0.5, most preferably at least about 0.8, and / or in a range of not greater than about 1.0, preferably not greater than about 0.8, more preferably not greater than about 0.5, most preferably not greater than about 0.3. More preferably, a difference s0- s u between the upper weighting factor s0 and the lower weighting factor s unot greater than about 1.0, preferably not greater than about 0.8, more preferably not greater than about 0.5, even more preferably not greater than about 0.3, or even not greater than about 0.2, most preferably not greater than about 0.1.

[0033] In a preferred variant, the upper weighting factor s0 and the lower weighting factor s u a positive weighting factor s. In other words, the horizontal extent r'h and / or the vertical extent r'v of the central main viewing area is / are preferably determined according to r'h = Th / (1 — sb' F) or according to r'v = r v Z (1 - sb' F) as a function of the primary refractive power F and the distance b' of the lens from the eye rotation point with a given reference value m for the horizontal extension or a given reference value r vfor the vertical extent of the central main viewing area and a predetermined positive weighting factor s, the value of which is in particular in a range of not more than about 1.0 and / or in a range of at least about 0.3, preferably at least about 0.5

[0034] Preferably, the method comprises:

[0035] Specifying a parameterization of a first refractive surface and a second refractive surface for the spectacle lens to be calculated or optimized; iteratively evaluating a target function and varying the parameterization of at least one of the refractive surfaces for the spectacle lens to be calculated or optimized to minimize the target function, wherein the target function defines at least one distribution of target specifications for the spherical equivalent across the spectacle lens such that for visual points that lie within the main visual area according to the determined horizontal and / or vertical extent of the main visual area, the target specifications for the spherical equivalent are set to the primary refractive power; and

[0036] Outputting the parameterization of the at least one varied refractive surface resulting from minimization of the objective function.

[0037] When calculating or optimising spectacle lenses, particularly when individually calculated or optimised (and then manufactured) spectacle lenses, it is desirable to achieve the best possible correction of a refractive error in the wearer's eye for different directions of view. In general, a spectacle lens is considered fully corrective for a given direction of view if the values ​​for sphere, cylinder and axis of the wavefront as it passes the vertex sphere (or an alternative assessment surface) match the values ​​for sphere, cylinder and axis of the prescription for the ametropia eye. When determining refraction for the eye of a spectacle wearer, dioptric values ​​(in particular sphere, cylinder, axis position - i.e. in particular sphero-cylindrical deviations) are used for a far (usually infinite) distance and, if necessary (for multifocal or progressive lenses), an addition for a near distance (e.g.B. according to DIN 58208) which should serve as the basis for the calculation or optimization (and thus for the production) of the spectacle lens.

[0038] However, complete correction for all directions of vision simultaneously is usually not possible. Therefore, the lenses are manufactured in such a way that they provide good correction of refractive errors and only minimal aberrations in the primary areas of use, especially in the central viewing areas, while allowing or even deliberately placing more significant aberrations in peripheral areas.

[0039] In order to manufacture a spectacle lens in this way, the lens surfaces, or at least one of the lens surfaces, are preferably first calculated in such a way as to achieve the desired distribution of the unavoidable and / or deliberately placed aberrations. This calculation and optimization is preferably carried out using an iterative variational method by minimizing an objective function. The objective function is, in particular, a function F z with the following functional relationship to the spherical effect S, the amount of the cylindrical effect Z and the axial position of the cylinder a (also called “SZA” combination) is taken into account and minimized:

[0040] In the objective function F zAt the assessment points / of the lens, at least the actual refractive deficiencies of the spherical power SA and the cylindrical power Z ,I as well as target values ​​for the refractive deficiencies of the spherical power SA ,SOII and the cylindrical power ZA ,SOII are taken into account. The distribution of the target values ​​or target values ​​and the weighting factors g t in the objective function is also called the design of the lens.

[0041] The basic procedure for calculating and optimizing spectacle lenses using such an objective function is fundamentally known. Within the scope of the present invention, however, it is proposed in a preferred embodiment that, with regard to the design of the spectacle lens, i.e., the spatial distribution of target specifications, at least the target specifications for the spherical component S of the power are defined across the spectacle lens in such a way that for visual points / that lie within the main visual range according to the determined horizontal and / or vertical extent of the main visual range, the target specifications for the spherical equivalent are defined for the primary refractive power F.

[0042] Preferably, the objective function also defines the distribution of target specifications for the spherical equivalent over the spectacle lens in such a way that for visual points that lie within the power range according to the determined horizontal and / or vertical extent of the main visual range, the target specifications for the spherical equivalent are set to the secondary refractive power, which is higher than the primary refractive power.

[0043] Preferably, a spectacle lens is calculated or optimized, which further comprises: a peripheral region outside the power range with a substantially constant refractive power which substantially corresponds to the substantially constant refractive power in the central main vision area, the method comprising:

[0044] Determination of a maximum horizontal and / or vertical extent of the field of effect based on (or as a function of) the primary refractive power (and preferably the distance b' of the lens from the eye pivot point).

[0045] In a further aspect, the invention relates to a method for producing a spectacle lens comprising:

[0046] Calculating or optimizing a spectacle lens according to the method for calculating or optimizing a spectacle lens in one of the embodiments described here; and

[0047] Manufacturing the calculated or optimized spectacle lens.

[0048] In a further aspect, the invention relates to a series of spectacle lenses comprising a plurality of spectacle lenses, each of which comprises: a central main viewing area, with a substantially constant refractive power, the primary refractive power; and an effective area adjacent to the central main viewing area, which at least partially causes a higher refractive power than the refractive power in the central main viewing area and / or at least partially causes a reduction in contrast (of an image through the spectacle lens), wherein the plurality of spectacle lenses of the series differ in pairs both in the value of the primary refractive power and in a horizontal and / or vertical extension of the central main viewing area in such a way thatthat between the lenses in the series, the horizontal and / or vertical extent of the central main visual area varies as a (at least partially) monotonically increasing function of the primary refractive power of the respective lens. In other words, in a pairwise comparison of two lenses in the series with different primary refractive powers, the horizontal and / or vertical extent of the central main visual area is greater for the lens with the greater (i.e., more positive or less negative) primary refractive power. In a preferred embodiment, the horizontal and / or vertical extent of the central main visual area within the series of lenses depends essentially on the primary refractive power in one of the functional ways described in connection with the methods for calculating or optimizing a lens.

[0049] In a further aspect, the invention provides a device for calculating or optimizing a spectacle lens for at least one eye of a spectacle wearer, such that the spectacle lens comprises: a central main viewing area with a substantially constant refractive power; and an effective area adjacent to the central main viewing area, which at least partially causes a higher refractive power, the secondary refractive power, than the refractive power in the central main viewing area and / or at least partially causes a reduction in contrast (of an image through the spectacle lens), wherein the device comprises: a data interface for acquiring user data comprising at least a spherical equivalent of a refractive deficit of the at least one eye;a determination module for determining a primary refractive power as the substantially constant refractive power of the central main visual area for correcting the spherical equivalent of the refractive deficit of the at least one eye; and a determination module for determining a horizontal and / or vertical extent of the central main visual area based on the primary refractive power;

[0050] Preferably, the device for calculating or optimizing a spectacle lens is designed to carry out a method for calculating or optimizing a spectacle lens in one of the preferred embodiments described here.

[0051] In a further aspect, the invention relates to a computer program product which, when loaded and executed on a computer, is designed to carry out a method for calculating or optimizing a spectacle lens according to one of the embodiments described here.

[0052] In a further aspect, the invention relates to a device for producing a spectacle lens comprising:

[0053] Calculation or optimization means designed to calculate or optimize the spectacle lens according to a method for calculating or optimizing a spectacle lens according to one of the embodiments described here;

[0054] Processing tools designed to finish the ophthalmic lens.

[0055] Finally, the invention relates to a use of a spectacle lens calculated or optimized according to the method according to one of the embodiments described here and / or a spectacle lens manufactured according to a manufacturing method described here for compensating a myopic refractive error and / or for reducing the progression of myopia.

[0056] The invention will now be further described using preferred embodiments with reference to the accompanying drawings. Figures 1 to 3 show schematic plan views of different examples of possible refractive power distributions on spectacle lenses manufactured according to the invention; and

[0057] Fig. 4 is a schematic representation of the beam path for a minus lens to illustrate conceptual explanations of the invention.

[0058] Fig. 1 shows a top view of an exemplary spectacle lens 10. In this example, the spectacle lens is initially shown as a raw, round spectacle lens (before edging). This raw, round spectacle lens can then be fitted into a corresponding frame, for example, along an edge 38 by edging.

[0059] As shown in Fig. 1, the spectacle lens 10 in this example comprises a central main viewing area 30 with a substantially constant refractive power, the primary refractive power F. This central main viewing area 30 is positioned in front of the respective eye of the wearer (user) by appropriately centering the spectacle lens such that the wearer, when looking in a principal viewing direction, essentially looks in the region of a center 36 of the central main viewing area 30. The spherical equivalent of the ametropia and preferably all refractive errors of the user's eye to be corrected are corrected as well as possible by the central main viewing area 30. This ensures that the user has sharp foveal vision in the principal viewing direction with this spectacle lens.

[0060] In addition, the spectacle lens comprises a power zone 32 adjacent to the central main field of vision 30, which in this case is arranged particularly around the central main field of vision 30. The power zone 32 produces an at least partially higher refractive power (positive dioptric additional power) than the refractive power in the central main field of vision 30 and / or at least partially a contrast reduction. This can be achieved, for example, at least partially by microstructures, for example in the form of microlenses (lenslets), in the power zone 32. In particular, in the case of a positive dioptric additional power in the power zone 32, the (middle) peripheral field of vision is imaged slightly in front of the retina of the corresponding eye of the wearer when vision is sharp in the central area (foveal vision).This suppresses the longitudinal growth of the eye, which leads to a reduction in the progression of a myopic characteristic of the eye and thus to better long-term wearing comfort for the lens.

[0061] In order to achieve a desired balance between tolerability and effectiveness of this myopia progression suppressing effect, a horizontal extension r'h and / or a vertical extension r' v of the central main viewing area 30 with the essentially constant refractive power F as a function of this refractive power (primary refractive power F), as will be described in more detail later by way of example.

[0062] Finally, in this variant, the spectacle lens 10 also comprises a peripheral region 34 outside the field of vision 32, again with a substantially constant refractive power. Particularly preferably, the substantially constant refractive power in the peripheral region 34 essentially corresponds to the substantially constant refractive power in the central main field of vision 30. Thus—assuming a substantially approximately isotropic eye length—the far peripheral field of vision is again imaged at least approximately sharply on the retina of the corresponding eye. This creates a pleasant visual sensation with a relatively wide field of vision and also increases safety when wearing the spectacle lens, since peripheral movements and thus potential obstacles and hazards can be detected earlier and more reliably by the wearer.Overall, this in turn contributes to better wearing comfort in the long term, especially if there is also a horizontal extension R'h and / or a vertical extension R'. v of the effective area 32 is in turn determined as a function of the primary refractive power F.

[0063] In the schematic, exemplary embodiment of Fig. 1, the central main viewing area 30 and the effective area 32 are shown circular. Thus, the central main viewing area 30 in this example has the same horizontal r'h and vertical extent r' v , in particular as the radius of the circular area forming the central main viewing area 30. Accordingly, in this example, the effective area 32 also has the same horizontal R'H and vertical extent R' v, in particular as the outer boundary radius of the circular ring forming the effective area 32. However, this is not necessarily the case. These areas can also have other shapes (e.g., oval). These areas do not necessarily have to be concentric with each other, even though this may be particularly advantageous for some universal applications.

[0064] In a preferred embodiment shown in Fig. 2, the power range 32 contains a near section 32-2, which lies within a segment of the spectacle lens and comprises a segment of the power range 32, which is bounded temporally by a vertical meridian line m1 downwards from the center of the central main field of vision 30 and nasally, in this case, by a meridian line m2, which is rotated nasally by approximately 30° to the vertical, downwards from the center of the central main field of vision. The optical properties of the segment of the power range encompassed by the near section 32-2 differ at least partially from the optical properties of the remaining power range 32-1, in particular with regard to their positive dioptric additional power and / or their contrast reduction.

[0065] While the embodiment of Fig. 1 could be implemented particularly as a single-vision lens, the embodiment of Fig. 2 is suitable, for example, as a progressive lens. Regarding the balance between tolerability and effectiveness for myopia management, both areas of application can benefit analogously from the inventive determination of the (maximum) extent of the central main visual field 30 as a function of the primary refractive power F.

[0066] Yet another example of a possible arrangement of an effective area is shown schematically in Fig. 3. In this case, a channel area 12 extends continuously from an upper edge 14 of the spectacle lens 10 to a lower edge 16 of the spectacle lens 10. This channel area 12 serves, when the correct prescription is applied for the corresponding eye, as a clear vision area or prescription area of ​​the spectacle lens 10 such that the user can see clearly through this area, since this area largely compensates for any ametropia of the eye.

[0067] The channel region 12 comprises in particular the central main viewing region 30, which can be used in particular for the user to look straight ahead (or to look into the distance towards the horizon) and which has a substantially constant primary refractive power F. On both sides (horizontally) adjacent to the channel region 12 and thus also to the central main viewing region 30 is the area of ​​effect, which in this example is divided into a nasal area of ​​effect 32n and a temporal area of ​​effect 32t, which in particular border directly on the channel region 12 along a respective nasal channel boundary line 26n or temporal channel boundary line 26t and thus also delimit the central main viewing region 30 at least in the horizontal extent m.The two power sections 32n, 32t together form the power range, in which the spectacle lens 10 essentially exhibits a higher refractive power and / or contrast reduction compared to the prescription data implemented in the canal area. This variant of an arrangement of the central main visual area 30 and power area 32 also benefits, with regard to the balance between tolerability and effectiveness of the effect for myopia management, from the inventive determination of the (maximum) extent of the central main visual area 30, at least in the horizontal direction, as a function of the primary refractive power F.

[0068] As already explained, a key idea is to reliably achieve the optimal balance between lens tolerability and their effectiveness in reducing the progression of myopia management for all corrective powers. To this end, it is proposed to create a basic design for a lens for myopia management with a central main visual field for good vision in this field and a peripheral field of effect that serves to control myopia progression. This basic design is designed to ensure an optimal distribution of tolerability on the one hand and the preventive effect on the other for a specific corrective power as a basic design reference (e.g., for F = 0 dpt).

[0069] As schematically shown in Fig. 4, the size a of the field of view of the central main visual area, which proves to be crucial for the compatibility of the glasses, can be determined by the radius of the central main visual area r, as well as the distance b' of the lens to the ocular center of rotation (significantly influenced by the HSA) (neglecting the inherent magnification of the lens). Essentially, the following applies:

[0070] - ab = r = - a' b'

[0071] The size of the field of view a, a' of the central main visual area varies for a constant physical size r on the lens due to the dynamic distortion caused by the corrective power according to a' = (1 - b' F) a, where F is the corrective power (spherical equivalent of the refractive power). For minus lenses (F < 0) used to correct myopia, this results in the size of the central field of view increasing with higher myopia, given the same (horizontal and / or vertical) extent of the central main visual area of ​​the lens. While this temporarily improves the tolerability of the lens, its tolerability and effectiveness for myopia management are no longer in optimal balance.

[0072] In order to ensure this optimal balance between compatibility and effectiveness for spectacle lenses with a wide variety of corrective powers, the size (i.e. the horizontal and / or vertical extent) of the central main visual area is adjusted based on the dynamic distortion (i.e. in particular based on the primary refractive power F of the spectacle lens), e.g. preferably according to r' = 1 / (1 - sb' F) r, where r' is the radius (in particular as a measure of a horizontal and / or vertical extent) of the adjusted central main visual area and s is a positive weighting factor, which is particularly preferably selected from a value range up to approximately 1. The value r is in particular a predetermined reference value for the (horizontal and / or vertical) extent of the central main visual area, which brings about the desired or predetermined balance in accordance with the basic design, in particular for F = 0.

[0073] As a result, the boundary between the central main field of vision and the effective range shifts depending on the refractive power, so that in a particularly reliable balance with greater myopia (and thus greater negative primary refractive power and therefore greater distortion of the lens), more area (or an area extending closer to the center) for the positive additional effect or the contrast reduction through the effective range is achieved.

[0074] This allows a single basic lens design to achieve a very wide range of different primary refractive power values ​​(i.e., different visual impairments) with at least an approximately consistently reliable balance between tolerability and myopia-stopping effect. This was not guaranteed in a similarly efficient and reliable manner with conventional lenses and their calculation, optimization, and manufacturing processes.

Claims

Patent claims 1 . A method for calculating or optimizing a spectacle lens for at least one eye of a spectacle wearer, such that the spectacle lens comprises: a central main viewing area (30) with a substantially constant refractive power; and an effective area (32) adjacent to the central main viewing area, which area produces an at least partially higher refractive power, the secondary refractive power, than the refractive power in the central main viewing area (30) and / or at least partially a contrast reduction, the method comprising: Providing user data comprising at least one spherical equivalent of a refractive deficit of the at least one eye; Determining a primary refractive power as the substantially constant refractive power of the central main visual area for correcting the spherical equivalent of the refractive deficit of the at least one eye; and Determination of a horizontal and / or vertical extent of the central main field of vision based on the primary refractive power.

2. Method according to claim 1, wherein the horizontal and / or vertical extent of the central main field of vision is determined as a monotonically increasing function of the primary refractive power of the spectacle lens.

3. Method according to claim 1 or 2, wherein the provided user data further comprises a distance measure which defines the distance b' of the spectacle lens to be calculated or optimized from the eye rotation point of the at least one eye; and wherein the horizontal and / or vertical extent of the central main visual area is determined based on the primary refractive power and the Distance measurement is or are determined.

4. The method according to claim 3, wherein the horizontal and / or vertical extent of the central main visual field is determined for a negative value of the primary refractive power as a monotonically decreasing function of the distance b' of the spectacle lens from the eye rotation point; and for a positive value of the primary refractive power, it is determined as a monotonically increasing function of the distance b' of the spectacle lens from the eye rotation point.

5. Method according to claim 3 or 4, wherein the horizontal extent r'h and / or the vertical extent r'v of the central main field of vision for negative values ​​of the primary refractive power according to rh / (1 - So b' F) < r'h < rh or according to Tv / (1 - So b' F) < r'v < r v and / or for positive values ​​of the primary refractive power according to rh < r'h < rh / (1 - So b' F) or according to Tv < r'v < Tv / (1 - So b' F) as a function of the primary refractive power F and the distance b' of the lens from the eye rotation point with a given reference value m for the horizontal extension or a given reference value r v for the vertical extent of the central main viewing area and a given positive upper weighting factor s0.

6. Method according to one of claims 3 to 5, wherein the horizontal extent r'h and / or the vertical extent r'v of the central main field of vision for negative values ​​of the primary refractive power according to rh / (1 - So b' F) < r'h < rh / (1 - Su b' F) or according to r v / (1 — So b' F) < r'v < r v / (1 - Su b' F) and / or for positive values ​​of the primary refractive power according to rh / (1 - Su b' F) < r'h < rh / (1 - So b' F) or according to r v / (1 — Su b' F) < r'v < r v / (1 - So b' F) as a function of the primary refractive power F and the distance b' of the lens from the eye rotation point with a given reference value m for the horizontal extension or a given reference value r v for the vertical extent of the central main viewing area as well as a given positive upper weighting factor s0 and a given positive lower weighting factor s u which is not greater than the upper weighting factor.

7. The method according to claim 5 or 6, wherein the upper weighting factor is in a range of not greater than about 1.5, preferably not greater than about 1.2, most preferably not greater than about 1.0 and / or in a range of at least about 0.3, preferably at least about 0.5, more preferably at least about 0.8, most preferably at least about 1.0; and / or wherein the lower weighting factor is in a range of at least about 0.1, preferably at least about 0.3, more preferably at least about 0.5, most preferably at least about 0.8, and / or in a range of not greater than about 1.0, preferably not greater than about 0.8, more preferably not greater than about 0.5, most preferably not greater than about 0.

3.

8. Method according to claim 6 or claim 7, insofar as it refers back to claim 6, wherein a difference s0- s u between the upper weighting factor s0 and the lower weighting factor s u not greater than about 1.0, preferably not greater than about 0.8, more preferably not greater than about 0.5, even more preferably not greater than about 0.3, or even not greater than about 0.2, most preferably not greater than about 0.

1.

9. Method according to claim 6 or claim 7, insofar as it relates back to claim 6, wherein the upper weighting factor s0 and the lower weighting factor s u correspond to a positive weighting factor s whose value lies in a range of not more than about 1.0 and / or in a range of at least about 0.3, preferably at least about 0.

5.

10. A method according to any one of the preceding claims, which comprises: Specifying a parameterization of a first refractive surface and a second refractive surface for the spectacle lens to be calculated or optimized; iteratively evaluating a target function and varying the parameterization of at least one of the refractive surfaces for the spectacle lens to be calculated or optimized to minimize the target function, wherein the target function defines at least one distribution of target specifications for the spherical equivalent across the spectacle lens such that for visual points that lie within the main visual area according to the determined horizontal and / or vertical extent of the main visual area, the target specifications for the spherical equivalent are set to the primary refractive power; and Outputting the parameterization of the at least one varied refractive surface resulting from minimization of the objective function.

11. The method according to claim 10, wherein the objective function determines the distribution of target specifications for the spherical equivalent over the spectacle lens in such a way that for visual points which lie within the power range according to the determined horizontal and / or vertical extent of the main visual range, the target specifications for the spherical equivalent are set to the secondary refractive power.

12. A method according to any one of the preceding claims for calculating or optimising a spectacle lens, which further comprises: a peripheral region (34) outside the power area (32) with a substantially constant refractive power which substantially corresponds to the substantially constant refractive power in the central main viewing area (30), the method comprising: Determine a maximum horizontal and / or vertical extent of the effective area based on the primary refractive power.

13. A method for producing a spectacle lens comprising: Calculating or optimizing a spectacle lens according to the method for calculating or optimizing a spectacle lens according to one of claims 1 to 12; and Manufacturing the calculated or optimized spectacle lens.

14. A series of spectacle lenses comprising a plurality of spectacle lenses, each of which comprises: a central main vision region (30) with a substantially constant refractive power, the primary refractive power; and an effective region (32) adjacent to the central main vision region, which at least partially causes a higher refractive power than the refractive power in the central main vision region (30) and / or at least partially causes a reduction in contrast, wherein the plurality of spectacle lenses of the series differ in pairs both in the value of the primary refractive power and in a horizontal and / or vertical extent of the central main visual area in such a way that between the spectacle lenses of the series the horizontal and / or vertical extent of the central main visual area varies as a monotonically increasing function of the primary refractive power of the respective spectacle lens.

15. A device for calculating or optimizing a spectacle lens for at least one eye of a spectacle wearer, such that the spectacle lens comprises: a central main viewing area (30) with a substantially constant refractive power; and an effective area (32) adjacent to the central main viewing area, which area produces an at least partially higher refractive power, the secondary refractive power, than the refractive power in the central main viewing area (30) and / or at least partially reduces contrast, wherein the device comprises: a data interface for acquiring user data comprising at least a spherical equivalent of a refractive deficit of the at least one eye; a determination module for determining a primary refractive power as the substantially constant refractive power of the central main viewing area for correcting the spherical equivalent of the refractive deficit of the at least one eye;and a determination module for determining a horizontal and / or vertical extent of the central main field of view based on the primary refractive power; 16. A computer program product which, when loaded and executed on a computer, is designed to carry out a method for calculating or optimizing a spectacle lens according to one of claims 1 to 12.

17. Apparatus for producing a spectacle lens comprising: Calculation or optimization means configured to calculate or optimize the spectacle lens according to a method for calculating or optimizing a spectacle lens according to one of claims 1 to 12; processing means configured to finish the spectacle lens.

18. Use of a spectacle lens calculated or optimized according to the method according to one of claims 1 to 12 and / or manufactured according to a manufacturing method according to claim 13 for correcting myopic refractive error.

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