Gradient spectacle lens

Abstract

The invention relates to a progressive spectacle lens. An ophthalmic lens, the ophthalmic lens comprising: a central viewing region having a refractive power providing a first stable power region; a lower viewing region having a refractive power providing a second stable power region; and two peripheral viewing regions having refractive powers that provide a third stable power region and a fourth stable power region, respectively; and an upper viewing region having a refractive power providing a fifth stable power region, where each of the second, third, fourth, and fifth stable power regions provides a greater refractive power than the refractive power provided by the first stable power region.

Description

Technical Field

[0001] The invention relates to a progressive spectacle lens, a method for producing a progressive spectacle lens, and a computer program comprising instructions which, when a computer executes the program, cause the computer to perform the steps of the method for producing a progressive spectacle lens. Background Art

[0002] As described in Holden, BA; Fricke, TR; Wilson, DA; Jong, M.; Naidoo, KS; Sankaridurg, P.; Wong, TY; Naduvilath, TJ; Resnikoff, S., Global Prevalence of Myopia and High Myopia and Temporal Trends from 2000 through 2050, Ophthalmology, 2016, vol. 123, pp. 1036-1042, doi:10.1016 / j.ophtha.2016.01.006; Morgan, IG; He, M.; French, AN; Rose, KA, A New Epidemic of High Myopia and Pathologic Myopia? =], Cataract Refract. Surg. Today Eur., June 2016, pp. 70-73; Williams, KM; Bertelsen, G.; Cumberland, P.; Wolfram, C.; Verhoeven, VJ; Anastasopoulos, E.; Buitendijk, GH, Increasing Prevalence of Myopia in Europe and the Impact of Education, Ophthalmology, 2015, vol. 122, pp. 1489-1497; and Vitale, S.; Sperduto, RD; Ferris, FL, Increased prevalence of myopia in the United States between 1971-1972and 1999-2004 [Increase in the prevalence of myopia in the United States between 1971-1972 and 1999-2004], Arch. Ophthalmol., 2009, Vol. 127, pp. 1632-1639, in more detail, epidemiological surveys from different parts of the world have documented an increase in the prevalence of myopia.Myopia not only blurs distance vision but also increases the risk of macular degeneration, retinal detachment, and glaucoma later in life due to pathological changes in the retina and choroid associated with extensive elongation of the eye; see, e.g., Saw, S.-M.; Gazzard, G.; Shih-Yen, EC; Chua, WH. Myopia and associated pathological complications, Ophthalmic Physiol Opt., 25, 381-391, 2005; Chiang, PP-C.; Fenwick, E.; Cheung, CMG; Lamoureux, E., in Public Health Impact of Pathologic Myopia, in Spaide RF, Ohno-Matsui K, Yannuzzi LA, eds., Pathologic Myopia, New York, USA: Springer, 2014, 75-81. Therefore, it would be desirable to improve preventive treatment of myopia during childhood when myopia progression and axial elongation are most rapid.

[0003] Based on experimental results showing that hyperopic retinal defocus lengthens the axial length of the eye, leading to myopia progression, and that a sharply focused image on or in front of the retina acts as a stop signal for the elongation, the use of progressive spectacle lenses that reduce both accommodative lag and hyperopic defocus on the peripheral retina have been proposed to produce a delaying effect on myopia progression, see, e.g., Wolffsohn JS., Flitcroft D.I., Gifford KL, et al., IMI–Myopia control reports overview and introduction, Invest. Ophthalmol. Vis. Sci., 60, 2019, M1–M19; and Wildsoet CF, Chia A., Cho P., et al., IMI–Interventions for Controlling Myopia Onset and Progression. Report [IMI – Report on Interventions to Control Myopia Onset and Progression], Invest.Ophthalmol.Vis.Sci., No. 60, 2019, M106–M131.

[0004] US 4,786,160 A discloses a multifocal spectacle lens having two gradient zones that are spatially separated from each other and that provide a smooth power transition between three different viewing distance zones. The gradient surface is calculated according to a spline analysis technique and is twice continuously differentiable. In a particular embodiment, the gradient lens has a central viewing zone for distance vision, a lower viewing zone with a lower addition of +1.75D for near vision, and an upper viewing zone with a lower addition of +1.00D for intermediate vision.

[0005] US 6,343,861 B1 discloses a progressive ophthalmic lens element, which includes a lens surface having: an upper viewing zone, the upper viewing zone having a surface for achieving a refractive power corresponding to far vision; a lower viewing zone, the lower viewing zone having a surface focal length greater than that of the upper viewing zone for achieving a refractive power corresponding to near vision; and an intermediate zone extending on the lens element, the intermediate zone having a surface focal length varying from the surface focal length of the upper viewing zone to the surface focal length of the lower viewing zone and including a corridor zone of relatively low surface astigmatism, the progressive ophthalmic lens element including progressive design elements, which are selected to reduce myopia progression.

[0006] US 7,862,171 B2 discloses an ophthalmic lens element for correcting myopia of an eye of a wearer. The lens element comprises a central viewing zone and a peripheral zone. The central viewing zone provides a first optical correction for substantially correcting myopia associated with a foveal region of the eye of the wearer. The peripheral zone surrounds the central viewing zone and provides a second optical correction for substantially correcting myopia or hyperopia associated with a peripheral region of the retina of the eye of the wearer. A system and method for dispensing or designing an ophthalmic lens element for correcting myopia of an eye of a wearer is also disclosed.

[0007] US 8,540,365 B2 discloses an ophthalmic lens element comprising a front surface and a back surface, wherein at least one of the surfaces comprises a horizontal meridian plane and a vertical meridian plane. The central viewing zone of the lens element comprises a foveal viewing zone, which provides a first focal power to provide a wearer with clear foveal vision. It also comprises a peripheral region having a positive focal power relative to the first focal power. The peripheral region comprises a double gradient zone, which is located on both sides of the vertical meridian plane and extends radially outward from the central viewing zone. The lens element provides a surface astigmatism distribution, which provides a relatively low surface astigmatism in the central viewing zone and the gradient zone on the horizontal meridian plane.

[0008] US 8,833,936 B1 discloses a progressive ophthalmic lens having an upper viewing zone, a lower viewing zone, a corridor band, and a peripheral area arranged on each side of the lower viewing zone. The upper viewing zone includes a distance reference point (DRP) and a fitting cross (FC) and provides a first refractive power for far vision. The lower viewing zone for near vision provides a lower addition relative to the first refractive power. The corridor band connects the upper zone and the lower zone and provides a refractive power that changes from the refractive power of the upper viewing zone to the refractive power of the lower viewing zone. Each peripheral area includes a positive power zone relative to the lower addition, wherein a positive refractive power is provided relative to the refractive power of the lower viewing zone. The relatively positive power zone is arranged adjacent to the lower viewing zone so that the lower viewing zone is inserted into the relatively positive power zone.

[0009] EP 2 069 854 B1 discloses an ophthalmic lens element comprising a central viewing zone of low surface astigmatism, and a peripheral zone. The central viewing zone comprises an upper viewing zone of a first focal power for providing a distance vision task suitable for the wearer. The peripheral zone has a positive focal power relative to the first focal power and surrounds the central viewing zone. The peripheral zone provides an optical correction for delaying or preventing myopia of the wearer and comprises one or more regions of relatively high surface astigmatism, a lower viewing zone or near viewing zone of low surface astigmatism, and a corridor zone of low surface astigmatism having a surface focal power varying from the surface focal power of the upper viewing zone to the surface focal power of the lower viewing zone. The lower viewing zone is for the near vision task of the wearer.

[0010] In the following article, Hasebe S., Jun J., Varnas SR, Myopia control with positively aspherized progressive addition lenses: a 2-year, multicenter, randomized, controlled trial, Invest Ophthalmol Vis Sci., 2014, 55, 7177-7188, DOI: 10.1167 / iovs.12-11462, the effect of a newly designed progressive spectacle lens on the progression of early-onset myopia was evaluated, which progressive spectacle lenses both reduced accommodative lag and reduced hyperopic defocus on the peripheral retina. The progressive spectacle lenses have relatively positive power in the peripheral zone of the lens compared to the central viewing zone, wherein the power and surface astigmatism are distributed in a manner that provides clear distance vision in the central viewing zone and clear near vision in the lower portion of the peripheral zone. In addition, the peripheral zone provides a positive average lower add in the upper part of the lens, intended as a stop signal for near vision progression. The area in the peripheral zone providing low astigmatism includes a near viewing zone, which is connected to the central viewing zone via an approximately umbilical corridor. Further, the progressive spectacle lens has a very short focal gradient corridor, which is suitable for use by children or adolescents, reaching the full nominal lower add 14 mm below the fitting point. However, positive aspherization of the distance zone of the progressive spectacle lens with an astigmatic surface extension does not result in a higher efficacy in controlling myopia progression compared to conventional progressive spectacle lenses without such positive aspherization.

[0011] WO 2013 / 134825 A1 discloses an ophthalmic lens element comprising an upper viewing zone for distance and a lower viewing zone for near. The upper viewing zone for distance comprises a central region having a first refractive power for clear distance vision and a peripheral region having a relatively positive focal power compared to the first refractive power. The lower viewing zone for near has a central region having a relatively positive focal power compared to the first refractive power to account for accommodative hysteresis. The focal power of the peripheral region of the lower viewing zone for near is one of the following: i) equal to the focal power of the central region of the lower viewing zone for near, ii) relatively positive compared to the focal power of the central region of the lower viewing zone for near.

[0012] Further background of the present invention is disclosed in CN 110 068 938 A, US 2004 / 008320 A1 and US 6,390,623 B1.

[0013] Despite the advantages of the above-described progressive spectacle lenses, there is still room for further improvement in enhancing the preventive treatment of myopia in children, particularly in the contemporary environment characterized by the intensive use of computer devices. Summary of the invention

[0014] In particular with regard to the disclosure of any of WO 2013 / 134825 A1, EP 2 069 854 B1 and Hasebe S. et al. (see above), the object of the present invention is therefore to provide a progressive spectacle lens, a method for producing a progressive spectacle lens and a computer program comprising instructions which, when a computer executes the program, cause the computer to perform the steps of the method for producing a progressive spectacle lens, at least partially overcoming the above-mentioned problems in the prior art.

[0015] A particular object of the present invention is to correct the relative peripheral hyperopic drift of the eye of a wearer of progressive spectacle lenses during distance vision tasks when looking straight ahead, and at the same time, to reduce accommodative lag during both near vision tasks (such as reading) and viewing objects at intermediate viewing distances (such as the screen of a computer monitor).

[0016] This problem is solved by a progressive spectacle lens, a method for producing a progressive spectacle lens, and a computer program comprising instructions which, when a computer executes the program, cause the computer to perform the steps of the method for producing a progressive spectacle lens having the features of the independent claims. Preferred embodiments are listed in the dependent claims and in the entire description, which can be realized in isolation or in any combination.

[0017] In a first aspect, the invention relates to a progressive spectacle lens, wherein the progressive spectacle lens has a front surface and a back surface, wherein the front surface or the back surface is a progressive surface, the progressive surface comprising:

[0018] a central viewing zone having a surface power providing a first refractive power for distance vision;

[0019] a lower viewing zone having a greater surface power than the central viewing zone, providing a second refractive power corresponding to near vision, wherein the lower viewing zone is connected to the central viewing zone by a first progressive power region having a surface power that varies from a surface power of the central viewing zone to a greater surface power of the lower viewing zone and having a corridor band of low surface astigmatism;

[0020] two peripheral viewing zones extending laterally from a vertical meridian plane of the progressive surface, each peripheral viewing zone having a greater surface power than the central viewing zone, providing a third refractive power at the prescribed field angle to correct a peripheral hyperopic shift of a stationary eye looking straight ahead, wherein each peripheral viewing zone is connected to the central viewing zone by a second progressive power region having a surface power varying from the surface power of the central viewing zone to a greater surface power of each peripheral viewing zone and having a corridor band of low surface astigmatism; and

[0021] An upper viewing zone, which has a larger surface focality than the central viewing zone, provides a fourth refractive power corresponding to the visual center, wherein the upper viewing zone is connected to the central viewing zone by a third gradient focality area, the third gradient focality area having a surface focality varying from the surface focality of the central viewing zone to the surface focality of the upper viewing zone and having a corridor band of low surface astigmatism.

[0022] Based on section 3.5.2 of the standard ISO 13666:2019 (Ophthalmic optics – Spectacle lenses – Vocabulary, herein also referred to as the “standard”), the term “spectacle lens” refers to an optical lens for determining and / or correcting at least one ocular aberration of an eye of a wearer, wherein the spectacle lens is carried in front of the eye of the wearer. In addition to the term “wearer”, different terms may also be applied, such as “subject”, “person”, “test person” or “user”. Further, section 3.7.8 of the standard defines the term “progressive spectacle lens” as a specific kind of spectacle lens having a progressive surface comprising at least two optical power reference points, which spectacle lens is generally designed to provide correction of presbyopia and clear vision from far to near. In particular, a progressive spectacle lens has a primary reference point also referred to as “DRP” and a secondary reference point referred to as “near reference point” or “NRP”.

[0023] Further, the term "eye aberration" refers to the difference between the surface of the ideal optical wavefront determined for the wearer's eye and the surface of the actual optical wavefront. Herein, the term "optical wavefront" refers to the surface perpendicular to the light along which the light propagates. In particular, within a typical human population, eye aberrations typically include at least one second-order sphero-cylindrical focusing error, also known as "refractive error". Various methods can be used to describe sphero-cylindrical lenses designed to correct sphero-cylindrical focusing errors. As defined in Section 3.6.6 of the standard, the term "sphero-cylindrical lens" refers to a spectacle lens having a spherical surface and a cylindrical surface. Further, according to Section 3.13.1, a sphero-cylindrical lens is defined as a spectacle lens that combines parallel paraxial beams on two separate mutually perpendicular focal lines, whereby the spectacle lens has refractive power only in two meridian planes. As commonly used, the term "refractive power" refers to a measurement of the degree to which a spectacle lens converges or diverges incident light. Further, according to Section 3.10.7, the term "vertex focal power" is defined as the reciprocal value of the width of the paraxial section. As further defined in Sections 3.2.12 and 3.13.2, the term "meridian plane" refers to one of the two perpendicular planes of a spectacle lens having an astigmatic effect parallel to the two focal lines. Further, the term "astigmatic effect" or "astigmatic power" corresponds to "astigmatism difference", which is defined in Section 3.13.6 as the difference between the vertex power value in the horizontal meridian plane and the refractive power value in the vertical meridian plane. As further commonly used, the term "surface astigmatism" refers to the measurement of the degree to which the curvature of a spectacle lens varies between cross planes, which are perpendicular to the surface of the spectacle lens at a point on the surface of the spectacle lens. Further, according to Section 3.13.7, "cylindrical power" refers to the algebraic difference between the refractive values ​​of these meridian planes, where the refractive value of a particular meridian plane used as a reference is subtracted from the refractive value of another meridian plane, and according to Section 3.13.8, "cylindrical axis" refers to the direction of the main meridian plane of the spectacle lens whose vertex power is used as a reference. As further defined in Section 3.10.4, the term "surface power" means the local ability of a finished surface to alter the convergence of a beam of light incident upon the surface, wherein the surface power is determined based on at least one radius of the surface and the refractive index of the optical material used for the progressive ophthalmic lens.

[0024] A progressive spectacle lens has a lens body comprising a front surface and a back surface, wherein the back surface faces the eye of the wearer and the front surface is hit first by an incident light beam incident on the progressive spectacle lens. Generally speaking, there are two types of progressive lenses, namely a first type having a progressive surface on the front surface of the optical lens and a prescription surface on the back surface selected from a spherical surface or a toric surface, and a second type having a spherical front surface and a back surface combining the progressive surface and the prescription surface. The first type is usually cast as a semi-finished progressive surface, after which the prescription surface is applied on the back surface. The second type is usually cast as a spherical disc with a spherical front surface, after which the back surface is processed with a free form generator and a polisher in order to obtain a complex surface combining the progressive surface and the toric surface.

[0025] The progressive spectacle lenses can be formulated from any suitable material, in particular a polymeric material. Herein, the polymeric material can be of any suitable type, in particular a thermoplastic or thermosetting material. In particular, materials of the diallyl carbonate type, such as CR-39 (PPG Industries) can be used. Herein, the polymer article can be formed from a crosslinkable polymer casting composition. Further, at least one of the front and rear surfaces can include at least one additive used in the casting composition, such as an inhibitor, a dye (including a thermochromic dye and a photochromic dye), a polarizer, a UV stabilizer, or a material capable of modifying the refractive index. Further, the progressive spectacle lenses can include an additional coating on at least one of the front or rear surfaces, in particular an electrochromic coating. Further, the front surface can include at least one of an anti-reflective (AR) coating or an abrasion-resistant coating. For further details, reference can be made to EP 2 069 854 B1.

[0026] According to the present invention, the progressive surface has a central viewing zone. As commonly used, the term "viewing zone" refers to a portion of a progressive surface that is designated to provide a refractive power for a particularly selected kind of vision. As commonly used, the terms "central viewing zone" and "distant viewing zone" both refer to a portion of a progressive surface that is located around the center of the progressive surface and is designated to provide a refractive power for far vision, specifically for providing foveal vision for on-axis viewing of a wearer of a progressive spectacle lens. The refractive power provided by the central viewing zone may typically be a prescription power corresponding to the optical correction required for the wearer's far vision. For the purpose of correcting myopia, the central viewing zone exhibits a negative power so as to bring an image from an uncorrected position in front of the retina to the retina of the wearer of the progressive spectacle lens. In particular, the central viewing zone may cover an area of ​​the progressive surface that corresponds to the typical eye rotation of the wearer.

[0027] Further according to the present invention, the gradient surface comprises four different stable lower light addition areas, which are located in the peripheral portion of the gradient surface of the gradient spectacle lens around the central viewing area in such a way that they surround the central viewing area. As commonly used, the term "periphery" refers to the portion of the gradient surface outside the central viewing area. According to the present invention, the peripheral portion provides a lower light addition of a first refractive power relative to the central viewing area throughout the peripheral portion. As commonly used, the term "lower light addition" refers to a partial refractive power provided in addition to the refractive power provided by the central viewing area.

[0028] The lower viewing zone is positioned along the lower portion of the vertical meridian plane of the progressive surface and provides a second refractive power corresponding to near vision. Therefore, the lower viewing zone may also be referred to as a "near viewing zone". Herein, the second refractive power provides a first lower addition of +1.00D to +4.00D, preferably +1.50D to +2.50D relative to the first refractive power of the central viewing zone, thereby providing a larger surface focal length than the central viewing zone. As generally used herein, the term "larger" means that the surface focal length of the corresponding viewing zone exceeds the surface focal length of the central viewing zone. In particular, the lower viewing zone can reduce the need for the wearer to tilt his head during near vision tasks (such as reading), and thus can make the lens more comfortable to wear. Further, the lower viewing zone can reduce the accommodative requirements imposed on the wearer's eyes for near vision tasks (such as reading). In particular, the lower viewing zone can help adolescent wearers reduce their accommodative requirements during near viewing tasks, which has been shown to have a non-negligible effect on delaying the progression of myopia.

[0029] Both peripheral visual zones extend from the vertical meridian of the progressive surface to both sides. The term "both sides" means that both peripheral visual zones are positioned along the horizontal meridian of the progressive surface in a manner symmetrical along the horizontal meridian of the progressive surface relative to the center of the progressive surface, specifically, the first peripheral visual zone is in the nasal direction of the progressive surface and the second peripheral visual zone is in the temporal direction of the progressive surface. Both peripheral visual zones are designed to provide a third refractive power at the prescription field angle, which is designed to correct the peripheral hyperopic drift of a stationary eye looking straight ahead. Herein, the third refractive power provides a second lower addition of +1.00D to +3.50D, preferably +1.50D to +2.00D relative to the first refractive power of the central viewing zone. As a result, the first lower addition can exceed the second lower addition by +0.50D or less, and in particular the first lower addition can be equal to the second lower addition.

[0030] In particular according to the present invention, the upper viewing zone is positioned along the upper part of the vertical meridian plane of the gradient surface, thereby pointing to the top of the gradient surface. Herein, the upper viewing zone is designated for providing a fourth refractive power corresponding to the visual center. As a result, the upper viewing zone can improve the viewing of objects at intermediate viewing distances (such as the screen of a computer monitor). Herein, the fourth refractive power provides a third lower light addition of +0.50D to +2.00D, preferably +0.75D to +1.50D relative to the first refractive power of the central viewing zone. As a result, both the first lower light addition and the second lower light addition can exceed the third lower light addition.

[0031] Further, the gradient surface includes a set of gradient power areas. As used herein, the term "gradient power area" refers to an area with a positive gradient of surface power, which is located on the gradient surface and is formed as a "corridor band" by connecting each of the central viewing area and the lower viewing area, the two peripheral viewing areas, and the upper viewing area. As commonly used, the term "corridor band" refers to a portion of the gradient surface that is designated to connect at least two separate viewing areas located on different parts of the gradient surface. According to the present invention, the lower light addition of each gradient power area increases with increasing distance from the center of the gradient surface, wherein the lower light addition increases until the corresponding lower light addition of the corresponding gradient power area is fully reached. As described in more detail below, each corridor band forming a gradient power area on a portion of the gradient surface simultaneously exhibits low surface astigmatism, wherein the term "low surface astigmatism" refers to a low degree of astigmatism power at the corresponding portion of the gradient surface, totaling less than +0.25. In contrast, higher surface astigmatism can exhibit astigmatism power up to +2.00D.

[0032] Conventional progressive lenses for presbyopes may include an intermediate viewing zone, which is located in the progressive zone between the distance viewing zone and the near viewing zone. In the progressive surface comprised by the progressive spectacle lens according to the present invention, the distance from the fitting cross (FC) in the central viewing zone to the near reference point (NRP) in the lower viewing zone is rather short. As a result, the remaining space is too small to fit in the intermediate viewing zone between the fitting cross and the near reference point. Therefore, the intermediate viewing zone is now constituted by an upper viewing zone located in the area above the distance viewing zone, whereby the distance from the fitting cross to the upper viewing zone is shorter than the distance from the fitting cross to the near viewing zone. In this context, the viewing of the monitor can be further improved by adjusting the height of the monitor, in particular slightly upwards, and / or by applying a slight downward tilt of the head when viewing the monitor in front of the wearer.

[0033] More specifically, both the first lower added light and the second lower added light can be fully reached at a first distance from the center of the gradient surface, wherein the first distance can be 12 mm to 20 mm, preferably 15 mm to 17 mm, and particularly 16 ± 0.1 mm. Similarly, the third lower added light of the upper viewing area can be fully reached at a second distance from the center of the gradient surface, wherein the first distance can preferably exceed the second distance, wherein the second distance can be 7 mm to 10 mm, preferably 8 mm to 9 mm, and particularly 8.5 ± 0.1 mm. However, other values ​​are also feasible.

[0034] Further, the progressive surface may include a set of blended regions. As commonly used, the term "blended region" refers to a region of the progressive surface having a non-prescription surface average power that provides only minimal visual utility. As used herein, the term "blended region" may specifically refer to a region located between two adjacent progressive power regions.

[0035] Further, the progressive spectacle lens comprises a specific distribution of surface astigmatism on the progressive surface. Herein, a low surface astigmatism of astigmatism power less than +0.25D is present in the central viewing zone, subject to the restrictions imposed by international standards on the power at the DRP, and extending from the central viewing zone to each of the lower viewing zone, the two peripheral viewing zones and the upper viewing zone through each of the progressive power zones connecting the central viewing zone with the corresponding lower viewing zone, the two peripheral viewing zones and the upper viewing zone, respectively. In contrast, a higher surface astigmatism of, for example, astigmatism power up to +2.00D may be present in a mixed zone located between two adjacent progressive power zones.

[0036] In another aspect, the invention relates to a series of progressive spectacle lenses, wherein a subsequent progressive spectacle lens in the series has a range of lower additions, wherein at least one of these lower additions is higher than the corresponding lower addition of a preceding progressive spectacle lens in the series, while the other lower additions are equal to or higher than the corresponding lower addition of the preceding spectacle lens in the series. In particular, the lower addition for the lower viewing zone for near vision may vary, such as in a conventional series of progressive lenses by an increment of +0.25D, while the other lower additions in the series may remain at the same level or increase by +0.25D, in particular depending on the peripheral refractive demand and the intermediate vision demand, respectively. As a particular advantage of the increment of the progressive spectacle lenses in the series, the preceding progressive spectacle lenses in the series may be used in particular in the early stages of myopia control treatment, while the subsequent progressive spectacle lenses in the series may be used in particular in the later stages of myopia control treatment, in particular in order to introduce an enhancement of the plus power, which may advantageously maintain the efficacy of the myopia control treatment during the later stages of treatment.

[0037] In another aspect, the present invention relates to a method for producing a progressive spectacle lens as disclosed elsewhere herein. The method according to the invention comprises the following steps a) and b), which can preferably be performed in a given order starting with step a) and continuing with step b), wherein, depending on the selected production method, these two steps can also be performed at least partially in a simultaneous manner. Furthermore, other steps disclosed or not disclosed herein can be additionally performed.

[0038] The steps of the method for producing a progressive spectacle lens of the present invention are as follows:

[0039] (a) determining, for a wearer of a progressive spectacle lens, a first value of a first refractive power for distance vision, a second value of a second refractive power corresponding to near vision, a third value of a third refractive power for correcting a peripheral hyperopic drift of a stationary eye looking straight ahead, and a fourth value of a fourth refractive power corresponding to intermediate vision; and

[0040] (b) producing a progressive spectacle lens by processing at least one lens blank using the first, second, third and fourth values ​​of optical correction, wherein the progressive spectacle lens has a front surface and a back surface, wherein the front surface or the back surface is a progressive surface as described elsewhere herein.

[0041] According to step (a), the respective values ​​of the corresponding refractive powers are determined, in particular by using the knowledge of a person skilled in the art. Based on the first, second, third and fourth values ​​of the optical correction, a progressive spectacle lens is then produced according to step (b) by machining at least one lens blank as is well known to a person skilled in the art.

[0042] In general, the method according to the invention can be performed in such a way that a lens blank can be provided and subsequently ground, for example by using a grinding device, in order to produce a desired progressive spectacle lens by using a first value, a second value, a third value and a fourth value of optical correction for compensating for at least one eye aberration in the wearer's eye.

[0043] However, in a preferred embodiment, the method according to the present invention can be a computer-implemented method. As commonly used, the term "computer-implemented method" refers to a method involving a programmable device (particularly a computer), a computer network or a readable medium carrying a computer program, thereby performing at least one method step, preferably all method steps, by using at least one computer program. For this purpose, the computer program code can be provided on a data storage medium or a separate device, such as an optical storage medium, for example, provided on a CD, directly provided on a computer or a data processing unit (particularly a mobile communication device, specifically a smart phone or a tablet computer), or provided via a network (such as an intranet or the Internet). Therefore, the inventive method can be performed on a programmable unit configured for this purpose, such as by providing a specific computer program.

[0044] Therefore, in another aspect, the present invention relates to a computer program which, when executed by a computer, causes the computer to perform the steps of the method for producing a progressive spectacle lens according to the present invention. For this purpose, the computer program may comprise instructions provided by means of a computer program code, which, when implemented on a computer or a data processing unit, are capable of performing any or all of the steps of the method as described elsewhere herein, and thus producing a spectacle lens for the eye of a wearer. Herein, the computer program code may be provided on a data storage medium or a separate device, such as an optical storage medium, for example on a compact disc, directly on a computer or a data processing unit (particularly a mobile communication device, in particular a smartphone or a tablet), or via a network (such as an intranet or the Internet).

[0045] For further details on the method for producing a progressive spectacle lens and the related computer program, reference may be made to the progressive spectacle lens as disclosed elsewhere herein.

[0046] A progressive spectacle lens, a method for producing a progressive spectacle lens and an associated computer program exhibit various advantages over the prior art. In particular, a progressive spectacle lens can be used in particular to suppress myogenic stimulation both during distance and near vision. This use of a progressive spectacle lens according to the invention is in particular in contrast to the following progressive spectacle lens described by Hasebe S. et al. (see above): attempts to positively aspherize the distance vision zone of a progressive spectacle lens with an astigmatic surface extension did not show a higher efficacy in controlling myopia progression compared to a conventional progressive spectacle lens without such positive aspherization.

[0047] Compared to the lens design concept described in WO 2013 / 134825 A1, the spectacle lens according to the present invention does not include a lower peripheral zone with an average focal power equal to or higher than the focal power of the near zone. On the contrary, the average focal power of the spectacle lens of the present invention in these zones is much smaller than the focal power of the near zone. Further, the spectacle lens of WO 2013 / 134825 A1 presents the zone from the far point to the near point as a single low astigmatism channel with a progressive focal power, wherein a discontinuous insertion in the peripheral zone or a blending of these high positive focal power zones by a blending zone with high astigmatism is proposed. In contrast, the spectacle lens of the present invention has 4 low astigmatism channels, which smoothly transition from one focal power to another until it reaches a stable focal power zone. Further, WO 2013 / 134825 A1 does not disclose an upper viewing zone for central vision.

[0048] Even taking into account other documents US 8,540,365 B2, US 8,833,936 B2 or US 6,390,623 B1, the skilled person would not consider it as a normal design procedure to achieve a low surface astigmatism profile in order to connect the different viewing zones of D1. All mentioned documents achieve the low surface astigmatism profile along one axis (vertical or horizontal). In contrast, our invention achieves these channels simultaneously along two axes, which are almost perpendicular to each other. Only this realization allows solving the problem in the design of ophthalmic lenses, namely providing plus power with low astigmatism in 4 different directions to meet the different requirements of young progressive myopic wearers for both foveal and peripheral vision.

[0049] As used herein, the terms "having", "including" or "comprising" or any grammatical variations thereof are used in a non-exclusive manner. Therefore, these terms can refer to the situation where no other features are present in the entity described in this context in addition to the features introduced by these terms, or the situation where one or more other features are present. As an example, the expressions "A has B", "A includes B" and "A contains B" can all refer to the situation where there are no other elements in A except B (i.e., the situation where A is composed only of B), or the situation where one or more other elements are present in entity A in addition to B, such as element C, element C and element D, or even other elements.

[0050] As further used herein, the terms "preferably", "more preferably", "particularly", "more particularly" or similar terms are used in conjunction with optional features without limiting the possibilities of substitution. Therefore, the features introduced by these terms are optional features and are not intended to limit the scope of the claims in any way. As the skilled person will recognize, the present invention can be implemented by using alternative features. Similarly, features introduced by "in an embodiment of the present invention" or similar expressions are intended to be optional features without any limitations on alternative embodiments of the present invention, without any limitations on the scope of the present invention, and without any limitations on the possibilities of combining the features introduced in this manner with other features of the present invention.

[0051] Preferably, other optional features and embodiments of the present invention are disclosed in more detail in the subsequent description of the preferred embodiment in conjunction with the dependent claims. Wherein, as will be appreciated by those skilled in the art, each optional feature of the dependent claims can be implemented in an isolated manner as well as in any feasible combination. It is emphasized here that the scope of the present invention is not limited by the preferred embodiment. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] The present invention will now be described with reference to the accompanying drawings, in which:

[0053] FIG. 1 shows the surface average focal power of a preferred embodiment of a progressive spectacle lens according to the present invention ( Figure 1A ) and surface astigmatism ( Figure 1B ) isoline map;

[0054] FIG. 2 shows the optical average power of a preferred embodiment of the progressive spectacle lens depicted in FIG. 1 ( Figure 2A ) and optical astigmatism ( Figure 2B ) isoline map;

[0055] FIG. 3 shows the surface average focal power of another preferred embodiment of the progressive spectacle lens according to the present invention ( Figure 3A ) and surface astigmatism ( Figure 3B ) isoline map;

[0056] FIG. 4 shows the optical average power of another preferred embodiment of the progressive spectacle lens depicted in FIG. 3 ( Figure 4A ) and optical astigmatism ( Figure 4B ); and

[0057] Figure 5 A preferred embodiment of the method according to the invention for producing a progressive spectacle lens is presented. DETAILED DESCRIPTION

[0058] Figure 1AA contour plot 110 of the surface average power 112 of a preferred exemplary embodiment of a progressive spectacle lens 114 according to the present invention is shown. As described above and described in more detail below, the progressive spectacle lens 114 proposed herein can preferably be used for myopia control, in particular for children's myopia control. The progressive spectacle lens 114 has a lens body, which can be transparent or at least partially transparent to an incident light beam so as to be able to correct at least one eye aberration of the wearer's eye. The lens body of the progressive spectacle lens 114 has a front surface and a back surface, wherein the back surface faces the wearer's eye and the front surface is first hit by the incident light beam incident on the progressive spectacle lens 114. Herein, the front surface or the back surface (preferably the back surface) of the progressive spectacle lens 114 can be combined with a progressive surface 116 described in more detail below, and a prescription surface, which prescription surface can include a complex curved component to correct the wearer's eye astigmatism, while the other surface (not depicted here) can be a spherical surface designated to provide long-distance viewing within a specific distance. As Figure 1A As further shown, the progressive surface 116 may typically be circular or slightly elliptical in form, with a center 118 where the vertical meridian plane 120 and the horizontal meridian plane 122 intersect each other. Herein, a fitting cross (FC) may be located at the center 118. Figures 1A to 4B As shown, each contour plot 110 shows the distribution of the corresponding variable over a diameter of 50 mm, which corresponds in an approximate manner to the size of a typical children's or youth frame.

[0059] like Figure 1A Schematically depicted, the progressive surface 116 has a central viewing zone 124, which is located around the center 118 of the progressive spectacle lens 114. The central viewing zone 124 is designated for providing a first refractive power, in particular over an area corresponding to a typical eye rotation of a wearer, wherein the first refractive power can preferably be adjusted to suit the wearer's distance vision task. Further, the progressive surface 116 has a peripheral portion 126, which surrounds the central viewing zone 124 and is adjusted to provide a lower addition light relative to the first refractive power provided by the central viewing zone 124 throughout the peripheral portion 126.

[0060] First, the lower viewing zone 128 is located within the peripheral portion 126 of the progressive surface 116 along the lower portion 130 of the vertical meridian plane 120. The lower viewing zone 128 is designated to provide a first lower light addition suitable for the wearer's near vision tasks (such as reading or looking at a computer keyboard). In an exemplary embodiment of the progressive surface 116, as shown in FIG. 1, the first lower light addition provided by the first stable lower light addition area 128 presents a value of about +1.50D relative to the first refractive power provided by the central viewing zone 124.

[0061] Further, two peripheral viewing zones 132, 134 extend from the horizontal meridian plane 122 to both sides within the peripheral portion 126 of the progressive surface 116, one in the temporal direction of the progressive surface 116 and the other in the nasal direction of the progressive surface. Herein, both peripheral viewing zones 132, 134 are designated to provide a second lower light addition at a prescription field angle, which is designed to correct the peripheral hyperopic drift of a still eye looking straight ahead. Figure 1A In the exemplary embodiment of the progressive surface 116 shown, the lower illumination of the two peripheral viewing zones 132 , 134 exhibits a value of approximately +1.50D, which is similar to the value of the first stable lower illumination area 128 .

[0062] According to the present invention, the upper viewing zone 136 is located within the peripheral portion 126 of the progressive surface 116 along the upper portion 138 of the vertical meridian plane 120, and is thus directed toward the top 140 of the progressive surface 116. Herein, the upper viewing zone 136 is designated to provide a third lower light that is designed to reduce the accommodative lag during viewing. As a result, the upper viewing zone 136 can improve the viewing of objects at intermediate viewing distances, such as the screen of a computer monitor. Figure 1A In the exemplary embodiment of the progressive surface 116 shown, the third lower added light of the upper viewing zone 136 presents a value of about +0.75D relative to the first refractive power provided by the central viewing zone 124. This value is much smaller than both the first lower added light of about 1.50D provided by the lower viewing zone 128 and the second lower added light of about 1.50D provided by the peripheral viewing zones 132, 134.

[0063] like Figure 1A As further schematically depicted in the figure, the gradient of the surface average focal length 112 from the center 118 of the gradient surface 116 to the first lower added light of approximately +1.50D in the lower viewing zone 128 and the second lower added light of approximately +1.50D in the peripheral viewing zones 132 and 134 is fully achieved at a first distance of 16±0.1 mm from the center 118 of the gradient surface 116, and in this exemplary embodiment, the third lower added light of approximately +0.75D in the upper viewing zone 136 is fully achieved at a second distance of approximately 8.5±0.1 mm from the center 118 of the gradient surface 116.

[0064] As a result of this exemplary arrangement, the gradient lengths of the first gradient focus area 142 connecting the central viewing zone 124 and the lower viewing zone 128, the second gradient focus area 144 connecting the central viewing zone 124 and the peripheral viewing zone 132, and the third gradient focus area 146 connecting the central viewing zone 124 and another peripheral viewing zone 134 greatly exceed the gradient length of the fourth gradient focus area 148 connecting the central viewing zone 124 and the upper viewing zone 136. In particular, the gradient lengths of the first gradient focus area 142 and the fourth gradient focus area 148 arranged in this manner may be beneficial in increasing compliance with the use of the lower viewing zone 128 for near vision and the upper viewing zone 136 for center vision.

[0065] Figure 1B Shown with Figure 1A 110 of a contour plot of the surface astigmatism 150 of the same exemplary embodiment of the progressive surface 116 of the progressive spectacle lens 114 depicted in FIG. Here, each progressive power zone 142, 144, 146, 148 as defined above is schematically depicted as having a low surface astigmatism, wherein the astigmatism power of the low surface astigmatism may be less than +0.25D, preferably close to zero.

[0066] like Figure 1B As further depicted in FIG. 1 , the peripheral portion 126 of the progressive surface 116 may also include mixed regions 152, 154, 156, 158 of high surface astigmatism, wherein each mixed region 152, 154, 156, 158 may be located between two adjacent progressive power regions 142, 144, 146, 148. Figure 1B In the exemplary embodiment of the progressive surface 116 shown, the astigmatism power of each blending region 152, 154, 156, 158 is between +0.75D and +1.25D. In this exemplary embodiment, the astigmatism power of other blending regions 152, 154 adjacent to the lower viewing zone 128 can particularly exhibit a higher astigmatism power of about +1.00D to +1.25D compared to the astigmatism power of the blending regions 156, 158 adjacent to the upper viewing zone 136 of about +0.75D to +1.00D.

[0067] Figure 2AA contour plot 110 of the optical mean power 160 distributed on the progressive surface 116 of a preferred exemplary embodiment of a progressive spectacle lens 114 schematically depicted in FIG1 is shown. Herein, the value of the optical mean power 160 is obtained by ray tracing. For this purpose, an analysis of the optical mean power 160 distributed on the progressive surface 116 is performed by simulating the process of measuring the progressive spectacle lens 114 on the progressive surface 116 using an ophthalmic instrument, in particular a spectacle meter or a focal meter, in particular a refractometer or a focus meter, in particular a Humphrey Lens Analyzer. For this purpose, the progressive spectacle lens 114 is positioned at a measuring point on the optical axis of the ophthalmic instrument, wherein the progressive surface 116 is placed flush with the measuring aperture. Parallel light on the side of the progressive spectacle lens 114 opposite to the measuring aperture is refracted by the progressive spectacle lens 114, thereby determining the final convergence of the light rays that directly pass through the measuring aperture to obtain the corresponding value of the optical mean power 160. In this regard, a configuration has been used in which the light rays are parallel to the optical axis of the ophthalmic instrument.

[0068] Figure 2B A contour plot 110 is shown of the optical astigmatism 162 distributed on the progressive surface 116 of the preferred exemplary embodiment of the progressive spectacle lens 114 schematically depicted in FIG1 . Herein, the value of the optical average astigmatism 162 is obtained by ray tracing with Figure 2A The optical average focal power 160 is obtained in a similar manner.

[0069] Figure 3A A contour diagram 110 of a surface average power 112 of another preferred exemplary embodiment of a progressive surface 116 of a progressive spectacle lens 114 according to the present invention is shown, and Figure 3B Shown with Figure 3A A contour plot 110 of the surface astigmatism 150 of the same another exemplary embodiment of a progressive surface 116 of a progressive spectacle lens 114 is depicted.

[0070] Figure 4A A contour map 110 showing the optical average focal power 160 is shown. Figure 4B A contour plot 110 of an optical astigmatism 162 is shown, both of which are distributed on a progressive surface 116 of a preferred exemplary embodiment of a progressive spectacle lens 114 schematically depicted in Fig. 3. For further details on determining the optical average power 160 and the optical astigmatism 162, reference may be made to the description of Fig. 2 above.

[0071] exist Figure 3A In another preferred exemplary embodiment, Figure 1A Compared to the preferred exemplary embodiment of the gradient surface 116 depicted, the gradient surface 116 has a higher downward light addition. Figure 3AIn this exemplary embodiment, the first lower added light in the lower viewing zone 128 along the vertical axis 120 presents a value of approximately +2.50D, the second lower added light in the peripheral viewing zones 132 and 134 along the horizontal axis 122 presents a value of approximately +2.00D, and the third lower added light in the upper viewing zone 136 presents a value of approximately +1.25D, each of which is additional to the first refractive power provided by the central viewing zone 124 of the gradient surface 116.

[0072] Therefore, relative to the progressive spectacle lens 114 depicted in FIGS. 1 and 2 , the progressive surface 116 depicted in FIGS. 3 and 4 may be considered as another progressive spectacle lens in a series of progressive spectacle lenses 114 .

[0073] As a result of this particularly preferred arrangement, the progressive spectacle lens 114 depicted in Figures 1 and 2 can be particularly used in the early stages of myopia control treatment, while the progressive spectacle lens 114 schematically depicted in Figures 3 and 4 can be particularly used in the later stages of myopia control treatment, specifically in order to introduce an enhancement of the plus power, which may advantageously maintain the efficacy of the myopia control treatment during the later stages of myopia control treatment.

[0074] Figure 5 A preferred embodiment of a method 170 for producing a progressive spectacle lens 114 according to the invention is shown.

[0075] In the determination step 172 according to step a),

[0076] Determining: a first value 174 of a first refractive power for far vision;

[0077] A second value of the second refractive power corresponding to near vision is 175;

[0078] a third value 176 of the third refractive power for correcting a peripheral hyperopic shift of the stationary eye looking straight ahead; and

[0079] A fourth value 177 of the fourth refractive power corresponding to the visual center.

[0080] In a production step 178 according to step b), a progressive spectacle lens 114 as described elsewhere herein is produced by machining at least one lens blank using the first value 174, the second value 175, the third value 176 and the fourth value 177 of the optical correction. As a result, the progressive spectacle lens 114 produced according to the production step 178 has a progressive surface 116 capable of performing a desired optical correction on the eye of a wearer of the progressive spectacle lens 114. Preferably, a set of glasses is produced that is capable of performing a desired optical correction on both eyes of the wearer simultaneously. In particular, the progressive spectacle lens 114 is capable of correcting the relative peripheral hyperopic drift of the wearer's eye during distance tasks when looking straight ahead and, at the same time, reducing the accommodative lag during both near tasks (such as reading) and viewing objects at an intermediate viewing distance (such as the screen of a computer monitor).

[0081] It should be understood that the above description is of exemplary embodiments of the present invention and that various changes and modifications may be made thereto without departing from the spirit and scope of the present invention as defined in the appended claims.

[0082] List of Reference Numerals

[0083] 110 Contour map

[0084] 112 Surface average focal length

[0085] 114 Gradient Spectacle Lenses

[0086] 116 Gradient Surface

[0087] 118 Center

[0088] 120 vertical meridian plane

[0089] 122 horizontal meridian plane

[0090] 124 Central Viewing Area

[0091] 126 Peripheral part (surrounding the central viewing area)

[0092] 128 Lower viewing area

[0093] 130 Lower part

[0094] 132 Peripheral Vision Area

[0095] 134 Peripheral Vision Area

[0096] 136 Upper Viewing Area

[0097] 138 Upper part

[0098] 140 Top

[0099] 142 First gradient focus area

[0100] 144 Second gradient focus area

[0101] 146 Second gradient focus area

[0102] 148 Third gradient focus area

[0103] 150 Surface astigmatism

[0104] 152 Mixed Area

[0105] 154 Mixed Area

[0106] 156 Mixed Area

[0107] 158 Mixed Area

[0108] 160 Optical average focal power

[0109] 162 Optical astigmatism

[0110] 170 Method for producing progressive spectacle lenses

[0111] 172 Determine the steps

[0112] 174 First Value

[0113] 175 Second value

[0114] 176 Third Value

[0115] 177 Fourth Value

[0116] 178 Production steps

Claims

1. A spectacle lens, comprising: a central viewing zone having an optical power providing a first region of stable power; a lower viewing zone having an optical power providing a second stable power region; and two peripheral viewing zones having refractive powers that provide a third region of stable power and a fourth region of stable power, respectively; and An upper viewing zone having a refractive power providing a fifth stable power zone, wherein each of the second, third, fourth and fifth stable power zones provides a greater refractive power than the first stable power zone. 2 . The eyeglass lens according to claim 1 , wherein the refractive power providing the second stable power area is +1.00D to +4.00D greater than the refractive power providing the first stable power area. 3 . The eyeglass lens according to claim 1 , wherein the refractive power providing the second stable power area is +1.50D to +2.50D greater than the refractive power providing the first stable power area. 4 . The eyeglass lens according to claim 1 , wherein the refractive power providing the third and fourth stable power areas is +1.00D to +3.50D greater than the refractive power providing the first stable power area. 5 . The eyeglass lens according to claim 1 , wherein the refractive power providing the third and fourth stable power areas is +1.50D to +2.00D greater than the refractive power providing the first stable power area. 6 . The eyeglass lens according to claim 1 , wherein the refractive power providing the fifth stable power area is +0.50D to +2.00D greater than the refractive power providing the first stable power area. 7 . The eyeglass lens according to claim 1 , wherein the refractive power providing the fifth stable power area is +0.75D to +1.50D greater than the refractive power providing the first stable power area.

8. An eyeglass lens according to claim 1, wherein the difference between the refractive power providing the second stable focal power area and the refractive power providing the first stable focal power area exceeds the difference between the refractive power providing the third and fourth stable focal power areas and the refractive power providing the first stable focal power area by +0.50D or less.

9. The eyeglass lens according to claim 1, wherein the difference between the refractive power providing the second stable focal power area and the refractive power providing the first stable focal power area is equal to the difference between the refractive power providing the third and fourth stable focal power areas and the refractive power providing the first stable focal power area.

10. An eyeglass lens according to claim 1, wherein the difference between the refractive power providing the second stable focal power area and the refractive power providing the first stable focal power area and the difference between the refractive power providing the third and fourth stable focal power areas and the refractive power providing the first stable focal power area exceeds the difference between the refractive power providing the fifth stable focal power area and the refractive power providing the first stable focal power area.

11. The eyeglass lens according to claim 1, wherein the refractive power providing the second stable power area and the refractive powers providing the third and fourth stable power areas are fully achieved at a first distance from the center of the surface.

12. The spectacle lens of claim 11, wherein the refractive power providing the fifth stable power zone is fully achieved at a second distance from the center of the surface, and wherein the first distance exceeds the second distance.

13. A series of spectacle lenses, each spectacle lens in the series being configured according to claim 1, wherein a subsequent spectacle lens in the series comprises a peripheral portion having a range of optical powers around the central viewing zone, wherein the optical powers are greater than the optical power providing the first stable focal power zone, and At least one of the second, third, fourth and fifth stable power zones is higher than the corresponding refractive power of the previous spectacle lens in the series, and the other refractive powers are equal to or higher than the corresponding refractive power of the previous spectacle lens in the series.

14. A series of spectacle lenses according to claim 13, wherein the difference between the second refractive power and the first refractive power of a subsequent spectacle lens in the series is increased by +0.25D relative to the difference between the second refractive power and the first refractive power of a previous spectacle lens in the series.

15. A series of spectacle lenses according to claim 13, wherein the difference between the third refractive power and / or the fourth refractive power and the first refractive power of a subsequent spectacle lens in the series is maintained or increased by +0.25D relative to the difference between the third refractive power and / or the fourth refractive power and the first refractive power of a previous spectacle lens in the series.

16. A series of spectacle lenses according to claim 13, wherein the difference between the fifth refractive power and the first refractive power of a subsequent spectacle lens in the series remains or increases by +0.25D relative to the difference between the fifth refractive power and the first refractive power of a previous spectacle lens in the series.

17. A method for providing a design of a spectacle lens by means of a computer so as to manufacture the spectacle lens based on the design, the spectacle lens having: a central viewing zone having a first optical power providing a first region of stable power; a lower viewing zone having an optical power providing a second region of stable power; and two peripheral vision zones having refractive powers providing a third stable power region and a fourth stable power region, respectively, The method includes: An upper viewing zone is provided having a refractive power providing a fifth stable power zone, wherein each of the second, third, fourth and fifth stable power zones provides a greater refractive power than the refractive power provided by the first stable power zone.

18. The method according to claim 17, further comprising: The spectacle lens is manufactured based on the design.

19. A non-transitory storage medium having a program stored thereon, the program comprising instructions which, when a computer executes the program, cause the computer to perform the method according to claim 17.

20. Design data of a spectacle lens for manufacturing a spectacle lens, the spectacle lens having: a central viewing zone having a first optical power providing a first region of stable power; a lower viewing zone having an optical power providing a second region of stable power; and two peripheral vision zones having refractive powers providing a third stable power region and a fourth stable power region, respectively, The design data is configured as: An upper viewing zone is provided having a refractive power providing a fifth stable power zone, wherein each of the second, third, fourth and fifth stable power zones provides a greater refractive power than the refractive power provided by the first stable power zone.

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