WO2025133357A1

WO2025133357A1 - Ophthalmic lens with modified peripheral curvature variation

Info

Publication number: WO2025133357A1
Application number: PCT/EP2024/088259
Authority: WO
Inventors: Mélanie HESLOUIS; Olivier Roussel; Cyril Guilloux
Original assignee: Essilor International Compagnie Generale dOptique SA
Current assignee: EssilorLuxottica SA
Priority date: 2023-12-22
Filing date: 2024-12-20
Publication date: 2025-06-26
Anticipated expiration: 2026-06-22

Abstract

The disclosure relates to an ophthalmic lens comprising: - a first face and a second face, each having a contour adapted such that the lens is mountable in a spectacle frame, and - a reference point O on the first face being disposed in front of a pupil of the wearer eye when the lens is mounted in a spectacle frame and in worn conditions, characterized in that for a point P_J of the arc A₁₂, the radial profile R_Pj of the first face, between O and P_J', spaced from P_J by 1 mm, has a radial curvature that changes of sign over a distance D_max, smaller or equal to 14 mm, from the point P_J' towards O, and in that for any point P_K of said first face contour out of said arc A₁₂, the radial profile R_Pk, between O and P_K', spaced from P_K by 1 mm, has a radial curvature that keeps its sign unchanged between O and P_K'.

Description

OPHTHALMIC LENS WITH MODIFIED PERIPHERAL CURVATURE VARIATION

TECHNICAL FIELD

[0001 ] The disclosure relates to an ophthalmic lens. More particularly, the disclosure relates to an ophthalmic lens having a variation of the curvature over a part of the peripheral portion.

BACKGROUND

[0002] Some of the existing ophthalmic lenses are known to involve aesthetic and mechanical issues.

[0003] Aesthetic disagreement may occur over the temporal side for myopic wearers. The aesthetic disagreement occurs on the nasal side for hyperopic wearers, for example due to the nose pad position for ophthalmic lens having a thick nasal portion.

[0004] A first mechanical issue is directed to the absence of total closing/fold of the temples of an eyewear for myopic wearer having ophthalmic lenses with thick temporal edges.

[0005] A second mechanical issue is related to the complexity to position the bevel on the peripheral portion of an ophthalmic lens due to the variability of the edge thickness.

[0006] A third issue is relative to the contact between the ophthalmic lens and the frame, more particularly at the location of the nose pads, temple and hinge. This can result in risk of damages of the ophthalmic lens as the location of the contact between the lens and the frame for example for myopic wearers eyewear.

[0007] The aim of the present disclosure is to provide a lens solving the above listed problem without impacting an optical function of the ophthalmic lens to be provided to the wearer, in the central portion.

SUMMARY OF THE DISCLOSURE

[0008] To this end, the disclosure relates to an ophthalmic lens for correcting a vision default of a wearer eye, the ophthalmic lens comprising a first face and a second face, each of said first and second face having a contour adapted such that the lens is mountable in a spectacle frame and a reference point O of the first face of the ophthalmic lens is disposed in front of a pupil of the wearer eye when the lens is mounted in the spectacle frame and in worn conditions, the first face contour comprising an arc A12 having a first and a second extremity Pi, P2, a radial profile Rn of the first face at the point Pi of the first face contour being an intersection of a plane comprising a normal direction to the first face at the reference point O and passing through the point Pi, characterized in that for at least one point Pj of the arc A12, the radial profile Rpj of the first face, between the reference point O and the point Pj comprising a point Pr spaced from the point Pj by 1 mm, has a radial curvature that changes of sign at least once over a distance D_max, smaller or equal to 14 mm, from the point Pj’ towards the reference point O, and in that for any point PK of said first face contour out of said arc A12, the radial profile Rpk of the first face, between O and PK comprising a point PK’ spaced from PK by 1 mm, has a radial curvature that keeps its sign unchanged between O and PK’.

[0009] Advantageously, this ophthalmic lens enables to address the aesthetic and mechanical issues mentioned above. By adapting the curvature (and the thickness) over the peripheral portion of the lens, a better housing of the ophthalmic lens can be performed without requiring the formation of a step. A step is unesthetic and may weaken the ophthalmic lens at the location where the thickness is the thinnest.

[0010] Advantageously, the ophthalmic lens according to the disclosure having a curvature variation overt the peripheral portion enables to not introduce any optical disturbance in the central portion of the lens, for example a cone of vision having a generatrix passing by passing by the retina and the optical center of the lens. Said cone having for example an opening angle lower or equal to 50°.

[0011] Preferably, the peripheral portion including a variation of curvature is located on the temporal side of the lens, when mounted in a spectacle frame and worn by the wearer, to ease the accommodation within said spectacle frame.

[0012] According to further embodiments of the method which can be considered alone or in combination: the reference point O of the first face of the ophthalmic lens is the optical center of the lens or the far vision reference point or the fitting cross; and/or - the change of sign of the radial curvature within the arc A12 has an angular sector smaller than or equal to 120°, and greater than or equal to 10°, disposed on the temporal side of the ophthalmic lens; and/or

- wherein at any point Pj of the arc A12, the radial profile Rpj of the first face, between the reference point O and the point Pj comprising a point Pj’ spaced from the point Pj by 1 mm, has a radial curvature that changes of sign at least once over a distance Dmax, smaller or equal to 14 mm, from the point Pr towards the reference point O; and/or

- the first extremity Pi having an azimuthal coordinate 0i in a cylindrical coordinate system R of the first face whose origin is on the reference point O, the second extremity P2 having an azimuthal coordinate 62 in the cylindrical coordinate system R, the arc A12 has an angular sector |02- 0i| greater than 10°, preferably greater than 45°; and/or

- the arc A12 is disposed on the temporal side of the ophthalmic lens, in worn conditions; and/or

- the distance D_max is lower than 9 mm, preferably lower than 6.5 mm; and/or for each radial profile Rpj„ between the point Pj within the arc A12 and the reference point O , a point Pr is located where the radial curvature changes of sign the first time when starting from the reference point O towards the point Pj, all together each of said points Pr form a continuous curve, wherein a projection of said continuous curve, according to the normal direction Z at the reference point O over a plane perpendicular to the normal direction to the first face at the reference point O, is non-circular; and/or

- the first face of the ophthalmic lens is the face of the lens which is the closest to the eye in worn condition; and/or

- wherein a point Pj of the arc A12 having an altitude coordinate Zpj in the cylindrical coordinate system R, a point Pr of the radial profile Rpj, between the reference point O and the point Pr, where the radial curvature changes the first time of sign from the reference point O towards the point Pj and being located at a distance Dj lower than the distance D_max from the point Pr and having an altitude coordinate Zpj” in the cylindrical coordinate system R, a virtual point Qj being an extrapolation of the part O Pr of the radial profile Rpj starting from the point Pr over the distance Dj, wherein said virtual point Qj has an altitude coordinate ZQ in the cylindrical coordinate system R, |Z • — Z '"I characterized in that 7-^ — -^7 < 1, preferably lower than 0.8 if the ophthalmic lens has a negative mean optical power at the reference point O and > 1,

preferably greater than 1.2 if the ophthalmic lens has a positive mean optical power at the reference point O; and/or

- the first face of the ophthalmic lens is the face of the lens which is the farthest to the eye in worn condition; and/or

- the point Pi of the arc A12 having an altitude coordinate Zpj in the cylindrical coordinate system R, a point Pr of the radial profile Rpj, between the reference point O and the point Pr, where the radial curvature changes the first time of sign from the reference point O towards the point Pj and being located at a distance Dj lower than the distance D_max from the point Pr and having an altitude coordinate Zpj” in the cylindrical coordinate system R, a virtual point Qj being an extrapolation of the part OPj” of the radial profile Rpj starting from the point Pr over the distance Dj, wherein said virtual point Qj has an altitude coordinate ZQJ in the cylindrical

coordinate system R, characterized in that > 1, preferably greater than

I ^ZQj “ ^ZPj" I

1.2 if the ophthalmic lens has a negative mean optical power at the reference point 0,

- —

< 1, preferably lower than 0.8 if the ophthalmic lens has a positive mean l^zQj " ^ZPj" I optical power the reference point O; and/or

- the ophthalmic lens is a progressive addition lens and the reference point O is the far vision reference point; and/or a mean optical power at the reference point O has an absolute value greater than 2 D; and/or

- the ophthalmic lens further comprises at least one optical element disposed between the first and second face, wherein said optical elements producing a stopping myopic optical signal towards the wearer eye.

[0013] The disclosure also relates to an eyewear comprising at least one ophthalmic lens according to the disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Non limiting embodiments of the disclosure will now be described, by way of example only, and with reference to the following drawings in which:

- Figures 1 and 2 show, diagrammatically, optical systems of eye and lens and ray tracing from the center of rotation of the eye;

Figure 3 shows the field vision zones of an ophthalmic progressive addition lens;

- Figure 4 shows the first face of a lens according to the disclosure in a cylindrical coordinate system;

Figure 5 shows the projection of the lens of figure 4 on a plane perpendicular to the normal direction to the first face at the reference point O; and

- Figure 6 shows the variation of the altitude over the radial profile Rpj.

DEFINITIONS

[0015] The following definitions are provided so as to define the wordings used within the frame of the present disclosure.

[0016] The wordings "wearer's prescription", also called "prescription data", are known in the art. Prescription data refers to one or more data obtained for the wearer and indicating for at least an eye, preferably for each eye, a prescribed sphere SPHp, and/or a prescribed astigmatism value CYLp and a prescribed axis AXISp suitable for correcting the ametropia of each eye for the wearer and a prescribed addition Add suitable for correcting the presbyopia of each of his eyes. The prescribed optical data, such as the prescribed optical power, the prescribed addition and/or the prescribed astigmatism, is transmitted by the ECP when he/she orders the ophthalmic lens to an ophthalmic lens manufacturer.

[0017] The prescribed optical power may comprise the prescribed far vision power corresponding to the optical power provided to the wearer to correct the visual impairment when the wearer is gazing at far distance.

[0018] The prescribed optical power may comprise the prescribed near vision power corresponding to the optical power provided to the wearer to correct the visual impairment when the wearer is gazing at near distance. [0019] The ophthalmic lens manufacturer prescribed addition usually inscribes information relative to the prescribed addition on the paper packaging of the delivered lens. The prescribed addition may be also determined from engravings located on the ophthalmic lens and still visible after the ophthalmic lens is edged and when mounted in said spectacle frame chosen by the wearer.

[0020] "Progressive ophthalmic addition lenses" are known in the art. According to the disclosure, the ophthalmic lens may be an unedged ophthalmic lens or a spectacle lens edged to be mounted in a spectacle frame. The ophthalmic lens may also be suitable for sunglasses All ophthalmic lenses of the disclosure may be paired so as to form a pair of lenses (left eye LE, right eye RE).

[0021] The wording “optical design” is a widely used wording known from the man skilled in the art in ophthalmic domain to designate the set of parameters allowing to defining an optical function of an ophthalmic lens. Each ophthalmic lens designer has its own designs, particularly for progressive ophthalmic lenses. As for an example, a progressive ophthalmic lens “design” results of an optimization of a progressive surface so as to restore a presbyope’s ability to see clearly at all distances but also to optimally respect all physiological visual functions such as foveal vision, extra-foveal vision, binocular vision, dynamic vision and to minimize unwanted astigmatisms. For example, a progressive lens design comprises: a power profile along the main gaze directions (meridian line) used by the ophthalmic lens wearer during day life activities, distributions of powers (mean power, astigmatism,...) on the sides of the ophthalmic lens, that is to say away from the main gaze direction.

[0022] These optical characteristics are part of the "designs" defined and calculated by ophthalmic lens designers and that are provided with the progressive lenses.

[0023] A "gaze direction" is identified by a couple of angle values (a,P), wherein said angles values are measured with regard to reference axes centered on the center lens O. More precisely, figure 1 represents a perspective view of an ophthalmic lens 1 and illustrating parameters a and P used defining a gaze direction. The angle alpha shown in figure 1 has a negative value. The main gaze direction may be defined for the couple of a angle values (a = 0°, p = 0°) [0024] In other embodiments, as illustrated on figures 8a to 16b, the reference axes are centered on the lens fitting point.

[0025] Figure 2 is a view in the vertical plane parallel to the antero-posterior axis of the wearer's head and passing through the center of rotation of the eye in the case when the parameter p is equal to 0. The center of rotation of the eye is labeled Q’. The axis Q’-F', shown on Figure 2 in a dot-dash line, is the horizontal axis passing through the center of rotation of the eye and extending in front of the wearer - that is the axis Q’-F' corresponding to the primary gaze direction. The ophthalmic lens is placed and centered in front of the eye such that the axis Q’-F' cuts the front face of the ophthalmic lens on a point called the fitting cross, which is, in general, present on lenses to enable the positioning of lenses in a frame by an optician. The point of intersection of the rear face of the ophthalmic lens and the axis Q’-F' is the point, O. A vertex sphere, which center is the center of rotation of the eye, Q’, and has a radius q' = O-Q’, intercepts the rear face of the ophthalmic lens in a point of the horizontal axis. A value of radius q' of 25 5 mm corresponds to a usual value and provides satisfying results when wearing the ophthalmic lenses. Other value of radius q' may be chosen. A given gaze direction, represented by a solid line on figure 1, corresponds to a position of the eye in rotation around Q’ and to a point J (see figure 2) of the vertex sphere.

[0026] The angle is the angle formed between the axis Q’-F' and the projection of the straight line Q’-J on the horizontal plane comprising the axis Q’-F'; this angle appears on the scheme on Figure 1.

[0027] The angle a is the angle formed between the axis Q’-J and the projection of the straight line Q’-J on the horizontal plane comprising the axis Q’-F'; this angle appears on the scheme on Figures 1 and 2.

[0028] A given gaze direction thus corresponds to a point J of the vertex sphere or to a couple (a,P). The more the value of the lowering gaze angle a is positive, the more the gaze is lowering and the more the value is negative, the more the gaze is rising. In a given gaze direction, the image of a point M in the object space, located at a given object distance, is formed between two points S and T corresponding to minimum and maximum distances JS and JT, which would be the sagittal and tangential local focal lengths. The image of a point in the object space at infinity is formed, at the point F'. The distance D corresponds to the rear frontal plane of the ophthalmic lens. [0029] For each gaze direction (a,P), a mean refractive power PPO(a,P), a module of astigmatism AST(a,P) and an axis AXE(a,P) of this astigmatism, and a module of resulting (also called residual or unwanted) astigmatism ASR(a,P) are defined.

[0030] "Astigmatism" refers to astigmatism generated by the ophthalmic lens, and “unwanted astigmatism” or resulting astigmatism corresponds to the difference between the ophthalmic lens-generated astigmatism and the prescribed astigmatism (wearer astigmatism); in each case, with regards to amplitude or both amplitude and axis.

[0031] In the sense of the disclosure, an “optical function” corresponds to a function providing for each gaze direction the effect of an optical lens on the light ray passing through the optical lens.

[0032] The optical function may comprise dioptric function, light absorption, polarizing capability, reinforcement of contrast capacity, etc...

[0033] The dioptric function corresponds to the optical lens power (mean power, astigmatism etc...) as a function of the gaze direction.

[0034] "Ergorama" is a function associating to each gaze direction the usual distance of an object point. Typically, in far vision following the primary gaze direction, the object point is at infinity. In near vision, following a gaze direction essentially corresponding to an angle a of the order of 35° and to an angle of the order of 5° in absolute value towards the nasal side, the object distance is of the order of 30 to 50 cm. For more details concerning a possible definition of an ergorama, US patent US-A-6, 318,859 may be considered. This document describes an ergorama, its definition and its modeling method.

[0035] For the purpose of the disclosure, points may be at infinity or not. Ergorama may be a function of the wearer's ametropia. Using these elements, it is possible to define a wearer optical power and astigmatism, in each gaze direction. An object point M at an object distance given by the ergorama is considered for a gaze direction (a,P). An object proximity ProxO is defined for the point M on the corresponding light ray in the object space as the inverse of the distance MJ between point M and point J of the vertex sphere:

ProxO = 1 /MJ [0036] This enables to calculate the object proximity within a thin lens approximation for all points of the vertex sphere, which is used for the determination of the ergorama. For a real lens, the object proximity can be considered as the inverse of the distance between the object point and the front face of the ophthalmic lens, on the corresponding light ray.

[0037] For the same gaze direction (a,0), the image of a point M having a given object proximity is formed between two points S and T which correspond respectively to minimal and maximal focal distances (which would be sagittal and tangential focal distances). The quantity Proxl is called image proximity of the point M:

[0038] By analogy with the case of a thin lens, it can therefore be defined, for a given gaze direction and for a given object proximity, i.e. for a point of the object space on the corresponding light ray, an optical power PPO as the sum of the image proximity and the object proximity.

PPO = ProxO + Proxl

[0039] The optical power is also called refractive power.

[0040] With the same notations, an astigmatism AST is defined for every gaze direction and for a given object proximity

[0041] This definition corresponds to the astigmatism of a ray beam created by the ophthalmic lens. The resulting astigmatism ASR is defined for every gaze direction through the ophthalmic lens as the difference between the actual astigmatism value AST for this gaze direction and the prescribed astigmatism. The unwanted astigmatism (resulting astigmatism) ASR more precisely corresponds to module of the vectorial difference between actual (AST, AXE) and prescription data (CYLp, AXISp).

[0042] When the characterization of the ophthalmic lens is of optical kind, it refers to the ergorama-eye-lens system described above. For simplicity, the term “lens” is used in the description but it has to be understood as the “ergorama-eye-lens system”. The values in optic terms can be expressed for gaze directions. Conditions suitable to determine of the ergorama- eye-lens system are called in the frame present disclosure "given wearing conditions".

[0043] In the remainder of the description, terms like « up », « bottom », « horizontal », «vertical », « above », « below », or other words indicating relative position may be used. These terms are to be understood in the wearing conditions of the ophthalmic lens. Notably, the "upper" part of the ophthalmic lens corresponds to a negative lowering angle a <0° and the "lower" part of the ophthalmic lens corresponds to a positive lowering angle a >0°.

[0044] A "far-vision gaze direction" is defined for an ophthalmic lens, as the vision gaze direction corresponding to the far vision (distant) reference point. Within the present disclosure, far-vision is also referred to as distant-vision. In the sense of the disclosure far vision is to be understood as vision at a distance greater than or equal to 4 meters.

[0045] A "near-vision gaze direction" is defined for an ophthalmic lens, as the vision gaze direction corresponding to the near vision (reading) reference point. In the embodiment of a progressive addition lens, the refractive power is substantially equal to the prescribed power in far vision plus the prescribed addition Add. In the sense of the disclosure near vision is to be understood as vision at a distance smaller than or equal to 50 cm. Here “substantially equal” means a “equal with a tolerance of at most 15%”. In this manner, a distance up to 57.5 cm is considered as a near vision distance.

[0046] An “intermediate-vision gaze direction” is defined for an ophthalmic lens, as the vision gaze direction corresponding to the intermediate vision (a person working in front of its computer desktop). In the sense of the disclosure intermediate vision is to be understood as vision at a distance greater than 50 cm, for example greater than 70 cm, and smaller than 4 meters, for example smaller than 1.5 m.

[0047] The "meridian line", referred as ML(a,P), of a progressive addition lens is a line defined from top to bottom of the ophthalmic lens and passing through the fitting cross where one can see clearly an object point. Said meridian line is defined on the basis of the repartition of module of resulting astigmatism, ASR, over the (a, P) domain and substantially correspond to the center of the two central iso-module of resulting astigmatism values which value is equal to 0.5 D. [0048] Figure 3 shows field vision zones of an ophthalmic progressive addition lens 30 where said lens comprises a far vision (distant vision) zone 32 located in the upper part of the ophthalmic lens, a near vision zone 36 located in the lower part of the ophthalmic lens and an intermediate vision zone 34 situated between the far vision zone 32 and the near vision zone 36. The meridian line is referred as 38.

[0049] The “wearing conditions” are to be understood as the position of the ophthalmic lens with relation to the eye of a wearer, for example defined by a pantoscopic angle, a Cornea to lens distance, a Pupil-cornea distance, a CRE to pupil distance, a CRE to lens distance and a wrap angle.

[0050] The Cornea to lens distance is the distance along the visual axis of the eye in the primary position (usually taken to be the horizontal) between the cornea and the rear face of the ophthalmic lens; for example equal to 12mm.

[0051] The Pupil-cornea distance is the distance along the visual axis of the eye between its pupil and cornea; usually equal to 2mm.

[0052] The CRE to pupil distance is the distance along the visual axis of the eye between its center of rotation (CRE) and pupil; for example equal to 11.5mm.

[0053] The CRE to lens distance is the distance along the visual axis of the eye in the primary position (usually taken to be the horizontal) between the CRE of the eye and the rear face of the ophthalmic lens, for example equal to 25.5mm.

[0054] The pantoscopic angle is the angle in the vertical plane, at the intersection between the rear face of the ophthalmic lens and the visual axis of the eye in the primary position (usually taken to be the horizontal), between the normal to the rear face of the ophthalmic lens and the visual axis of the eye in the primary position; for example equal to -8°.

[0055] The wrap angle is the angle in the horizontal plane, at the intersection between the rear face of the ophthalmic lens and the visual axis of the eye in the primary position (usually taken to be the horizontal), between the normal to the rear face of the ophthalmic lens and the visual axis of the eye in the primary position for example equal to 0°. [0056] An example of standard wearing condition may be defined by a pantoscopic angle of -8°, a Cornea to lens distance of 12 mm, a Pupil-cornea distance of 2 mm, a CRE to pupil distance of 11.5 mm, a CRE to lens distance of 25.5 mm and a wrap angle of 0°.

DETAILED DESCRIPTION OF THE DISCLOSURE

[0057] Figure 4 illustrates an ophthalmic lens 1 for correcting a vision default of a wearer eye in a cylindrical coordinate system R (g, 0, Z). The ophthalmic lens comprises a first face 12 (being the rear face of the ophthalmic lens 1 configured to face to the left eye of the wearer when mounted in the spectacle frame) and a second face. Each of said first and second faces has a contour adapted such that the lens 1 is mountable in a spectacle frame. More particularly, figure 4 illustrates the first face of the lens in the cylindrical coordinate system R.

[0058] The first face 12 of the ophthalmic lens 12 comprises a reference point O configured to be disposed in front of a pupil of the wearer eye when the lens 1 is mounted in a spectacle frame and in worn conditions.

[0059] The worn conditions may be standard wearing conditions.

[0060] The point O may be the optical center of the lens. The optical center may be defined as in ISO 13666:2019, section 3.2.15.

[0061] In an alternative embodiment, the ophthalmic lens may be a progressive addition lens and the reference point O may be the far vision reference point also referred to as the distance reference point in ISO 13666:2019, section 3.2.20 or the fitting cross also referred to as fitting point in ISO 13666:2019(EN), section 3.2.34.

[0062] The contour of the first face 12 comprises an arc An having a first and a second extremities, delimited by the point Pi and P2.

[0063] A radial profile Rpi of the first face at the point Pi of the first face contour is defined as the intersection of a plane with the first surface. The plane is defined according to the following constraints:

- the plane comprises a normal direction to the first face at the reference point O, and the plane includes the point Pi, and

- the plane may be defined by the condition that each point of said place as the same azimuthal coordinate Oi, in the cylindrical coordinate system R.

[0064] For at least one point Pj of the arc A12, a radial profile Rpj of the first face is to be considered. The radial profile Rpj extends between the reference point O and the point Pj according to the angular direction 0i of the cylindrical coordinate system R. The radial profile Rpj comprises, between the points O and Pj, a point Pp. The points Pj and Pp of the radial profile Rpj are located on the angular direction 0j of the cylindrical coordinate system R. The point Pp is spaced from the point Pj by 1 mm. The radial profile Rpj has a radial curvature that changes of sign at least once over a distance D_max from the point Pp towards the reference point O. The distance Dmaxis smaller or equal to 14 mm.

[0065] The curvature along the radial profile Rpj is defined by the following equation:

[0066] Wherein Z(g) defines the altitude of any point of first face 12 according to the he radial profile Rpj along the angle 0j:

Z₆(Q) = Z(Q - dp) + dZ(p - dp) + C₀(p - dp)

[0067] This equation enables the altitude of the first surface to be expressed with slope (first radial derivative) and curvature (linked to second radial derivative) constraints. Based on these two equations a link is provided between the variation of the curvature C₀j Cp) and the altitude Z_e(p).

[0068] Advantageously, the at least one change of sign of the radial curvature along the radial profile Rpj occurs in a peripheral portion 14 of the ophthalmic lens. In such manner, the optical function provided in the central portion 16 is not altered.

[0069] For any point PK of the contour of said first face, out of the arc An, the radial profile Rpk of the first face extends between the reference point O and the point PK according to the angular direction 0K of the cylindrical coordinate system R. The radial profile Rpk comprises a point PK’. The points PK and PK’ of the radial profile Rpkare located on the angular direction 0K of the cylindrical coordinate system R. The point PK’ is spaced from PK by 1 mm. The radial profile Rpk has a radial curvature that keeps its sign unchanged between O and PK’.

[0070] According to an embodiment, for any point Pj of the arc Al 2, the radial profile Rpj of the first face, between the reference point O and the point Pj comprises a point Pp. The point Pj’ is spaced from the point Pj by 1 mm. The radial profde Rpj has a radial curvature that changes of sign at least once over a distance D_max from the point Pr towards the reference point O. The distance Dmax is smaller or equal to 14 mm.

[0071] The first extremity, defined by the point Pl, defined by the coordinates (QI, 9I, ZI) in the cylindrical coordinate system R (shown in figure 1), whose origin is the reference point O. The second extremity, defined by the point P2, defined by the coordinates (92, 02, Z2) in the cylindrical coordinate system R.

[0072] The arc A12 is defined by an angular sector OP1P2. The angular sector is defined in the manner that the angle at the reference point defined by the equation |02- 0i| may be smaller than 120°, preferably smaller than 90° and greater than 10°, preferably greater than 45°.

[0073] In a preferred embodiment, when the lens 1 is mounted in a spectacle frame and in worn conditions, the arc A12 is disposed on the temporal side of the ophthalmic lens 1.

[0074] In a preferred embodiment, for the rear face of the ophthalmic lens 1 configured to face to the left eye of the wearer when mounted in the spectacle frame, in the cylindrical coordinate system R, the temporal side is defined for an angle 0i greater or equal to 90° and an angle 02 smaller or equal to 270°. And for the rear face of the ophthalmic lens 1 configured to face to the right eye of the wearer when mounted in the spectacle frame, in the cylindrical coordinate system R, the temporal side is defined for an angle 0i smaller or equal to 90° and an angle 02 greater or equal to 270°.

[0075] For example, the change of sign of the radial curvature within the arc A12 has an angular sector smaller than or equal to 120°, preferably smaller than or equal to 90°, and greater than or equal to 10°, preferably greater than or equal to 45°, disposed on the temporal side of the ophthalmic lens.

[0076] According to an embodiment, the distance Dmax is lower than 9 mm, preferably lower than 6.5 mm. Advantageously, the variation occurs closer to the contour of the first face 12. As Dmax diminishes, the portion of the lens having no variation of curvature, delimited by the radial distance “OPj — D_max — 1mm” increases.

[0077] In a particular embodiment, the first face 12 of the ophthalmic lens 1 is the face of the lens which is the closest to the eye in worn condition. [0078] A point Pj of the arc An has an altitude coordinate Zpj in the cylindrical coordinate system R, a point Pr (figure 5) of the radial profile Rpj is located between the reference point O and the point Pr The point Pr of the radial profile Rpj is located on the angular direction 0j of the cylindrical coordinate system R. At the point P , the radial curvature changes of sign the first time from the reference point O towards the point Pj. The point Pr is located at a distance Dj = Pj,Pj". The distance Dj is lower than the distance Dmax. The point Pr has an altitude coordinate Zpj” in the cylindrical coordinate system R.

[0079] For each radial profile Rpj„ between the reference point O and the point Pj within the arc A12,, the point Pr’ is located between the reference point O and the point Pj. At the location of the point Pj, the radial curvature changes of sign the first time when starting from the reference point O towards the point Pj. All together each of said points Pr within the angular sector OP1P2, between the angles 0i and 02, form a continuous curve.

[0080] A projection 18 of said continuous curve (shown in figure 5 as a dashed line comprising an alternation of short and long lines), according to the normal direction at the reference point O over a plane perpendicular to the normal direction to the first face at the reference point O, is non-circular. Said plane is defined such that Z is constant for any point of said plane.

[0081] A best fit portion circle 20 relative to the non-circular projected continuous curve 18 is determined. Preferably, the center of the best fit portion circle 20 is spaced from the projection of the reference point O by at least 4 mm.

[0082] All together said projected points Pr are spaced from the best fit portion circle 20 by more than 1 mm as an average.

[0083] A virtual point Qj being an extrapolation of the part OPr of the radial profile Rpj starting from the point Pr over the distance Dj, wherein said virtual point Qj has an altitude coordinate ZQ in the cylindrical coordinate system R

[0084] Figure 6 illustrates the variation of the of the altitude ₆J(Q) according to the radial profile Rpj of the ophthalmic lens according to the disclosure. Figure 6 also illustrates from the point Pr to the point Qj the virtual variation of curvature if no inflexion of the radial profile Rpj occurred at the point Pr. [0085] When, the wearer is myopic, the ophthalmic lens has a negative mean optical power at the reference point O, the following to ratio constraint is considered: l^ZPj ~ ^ZPj" l ₁ l ^ZQj “ ^ZPj" l

[0086] Preferably, this ratio is lower than 0.8.

[0087] When, the wearer is hyperopic, the ophthalmic lens has a positive mean optical power at the reference point O, the following to ratio constraint is considered:

[0088] Preferably, this ratio is higher than 1.2.

[0089] In another particular embodiment, the first face 12 of the ophthalmic lens 1 is the face of the lens which is the farthest to the eye in worn condition.

[0090] A point Pj of the arc A12 has an altitude coordinate Zpj in the cylindrical coordinate system R, a point Pr (figure 5) of the radial profile Rpj is located between the reference point O and the point Pr. The point Pr of the radial profile Rpj is located on the angular direction 0j of the cylindrical coordinate system R. At the point Py, the radial curvature changes of sign the first time from the reference point O towards the point Pj. The point Pj” is located at a distance Dj = Pj,Pj”. The distance Dj is lower than the distance D_max. The point Pr has an altitude coordinate Zpj” in the cylindrical coordinate system R.

[0091] For each radial profile Rpj„ between the reference point O and the point Pj within the arc A12,, the point Pp> is located between the reference point O and the point Pj. At the location of the point Pj, the radial curvature changes of sign the first time when starting from the reference point O towards the point Pj. All together each of said points Pr within the angular sector OP1P2, between the angles 0i and 02, form a continuous curve.

[0092] A projection 18 of said continuous curve (shown in figure 5 as a dashed line comprising an alternation of short and long lines), according to the normal direction at the reference point O over a plane perpendicular to the normal direction to the first face at the reference point O, is non-circular. Said plane is defined such that Z is constant for any point of said plane. [0093] A best fit portion circle 20 relative to the non-circular projected continuous curve 18 is determined. Preferably, the center of the best fit portion circle 20 is spaced from the projection of the reference point O by at least 4 mm.

[0094] All together said projected points Pr are spaced from the best fit portion circle 20 by more than 1 mm as an average.

[0095] A virtual point Qi being an extrapolation of the part OPr of the radial profile Rpj starting from the point Pr over the distance Dj, wherein said virtual point Qj has an altitude coordinate Zy, in the cylindrical coordinate system R.

[0096] Figure 6 illustrates the variation of the of the altitude Z₆j(p) according to the radial profile Rpj of the ophthalmic lens according to the disclosure. Figure 6 also illustrates from the point Pr to the point Qj the virtual variation of curvature if no inflexion of the radial profile Rpj occurred at the point Pr.

[0097] When, the wearer is myopic, the ophthalmic lens has a negative mean optical power at the reference point O, the following to ratio constraint is considered:

[0098] Preferably, this ratio is higher than 1.2.

[0099] When, the wearer is hyperopic, the ophthalmic lens has a positive mean optical power at the reference point O, the following to ratio constraint is considered:

[00100] Preferably, this ratio is lower than 0.8.

[00101] In an embodiment, the ophthalmic lens 1 is a progressive addition lens and the reference point O is the far vision reference point.

[00102] In an embodiment, the mean optical power at the reference point O has an absolute value greater than 2 D. [00103] Further, the disclosure addresses an ophthalmic lens 1 comprising at least one optical element disposed between the first and second face. For example, said at least one optical element is producing a stopping myopic optical signal towards the wearer eye.

[00104] Said at least one optical element may be a plurality of optical elements.

[00105] The plurality of optical elements is arranged over an annular zone centered on a reference point O of the lens element and having an inner diameter of 8 mm and an outer diameter of 17 mm. The ratio of the surface of the annular zone having an additional optical power greater than or equal to 7.5 D in absolute value and relative to the power at the reference point O, for example optical center, of the lens element over the total surface of the annular zone is greater than or equal to 0.02, for example greater than or equal to 0.05, for example greater than or equal to 0.09 and smaller than or equal to 0.5, for example smaller than or equal to 0.3.

[00106] Further, the disclosure also relates to an eyewear comprising at least one ophthalmic lens according to the previous disclosure.

[00107] The disclosure has been described above with the aid of embodiments without limitation of the general inventive concept.

[00108] Many further modifications and variations will suggest themselves to those skilled in the art upon making reference to the foregoing illustrative embodiments, which are given by way of example only and which are not intended to limit the scope of the disclosure, that being determined solely by the appended claims.

[00109] In the claims, the word “comprising” does not exclude other elements or steps, and the indefinite article “a” or “an” does not exclude a plurality. The mere fact that different features are recited in mutually different dependent claims does not indicate that a combination of these features cannot be advantageously used. Any reference signs in the claims should not be construed as limiting the scope of the disclosure.

Claims

1. An ophthalmic lens for correcting a vision default of a wearer eye, the ophthalmic lens comprising a first face and a second face, each of said first and second face having a contour adapted such that the lens is mountable in a spectacle frame and a reference point O of the first face of the ophthalmic lens is disposed in front of a pupil of the wearer eye when the lens is mounted in the spectacle frame and in worn conditions, the first face contour comprising an arc A12 having a first and a second extremity Pi, P2, a radial profile Rpi of the first face at the point Pi of the first face contour being an intersection of a plane comprising a normal direction Z to the first face at the reference point O and passing through the point Pi, characterized in that for at least one point Pj of the arc A12, the radial profile Rpj of the first face, between the reference point O and the point Pj comprising a point Pr spaced from the point PJ by 1 mm, has a radial curvature that changes of sign at least once over a distance D_max, smaller or equal to 14 mm, from the point Pj’ towards the reference point O, and in that for any point PK of said first face contour out of said arc A12, the radial profile Rpk of the first face, between O and PK comprising a point PK’ spaced from PK by 1 mm, has a radial curvature that keeps its sign unchanged between O and PK’.

2. The ophthalmic lens according to claim 1, wherein the reference point O of the first face of the ophthalmic lens is the optical center of the lens or the far vision reference point or the fitting cross.

3. The ophthalmic lens according to claim 1 or 2, wherein the change of sign of the radial curvature within the arc A12 has an angular sector smaller than or equal to 120°, and greater than or equal to 10°, disposed on the temporal side of the ophthalmic lens.

4. The ophthalmic lens according to any of the preceding claims, wherein at any point Pj of the arc A12, the radial profile Rpj of the first face, between the reference point O and the point Pj comprising a point Pj> spaced from the point Pj by 1 mm, has a radial curvature that changes of sign at least once over a distance D_max, smaller or equal to 14 mm, from the point Pj’ towards the reference point O.

5. The ophthalmic lens according to any of the preceding claims, wherein the first extremity Pi having an azimuthal coordinate 9i in a cylindrical coordinate system R of the first face whose origin is on the reference point O, the second extremity P2 having an azimuthal coordinate 62 in the cylindrical coordinate system R.

6. The ophthalmic lens according to one of claim 1 to 5, wherein the arc A12 is disposed on the temporal side of the ophthalmic lens, in worn conditions.

7. The ophthalmic lens according to one of claim 1 to 7, wherein the distance D_max is lower than 9 mm, preferably lower than 6.5 mm.

8. The ophthalmic lens according to one of claim 4 to 7, wherein for each radial profile Rpj„ between the point Pi within the arc A12 and the reference point O , a point Pr is located where the radial curvature changes of sign the first time when starting from the reference point O towards the point Pj, all together each of said points Pr form a continuous curve, wherein a projection of said continuous curve, according to the normal direction Z at the reference point O over a plane perpendicular to the normal direction to the first face at the reference point O, is non-circular.

9. The ophthalmic lens according to one of claim 1 to 8, wherein the first face of the ophthalmic lens is the face of the lens which is the closest to the eye in worn condition.

10. The ophthalmic lens according to one of claim 9, wherein a point Pj of the arc A12 having an altitude coordinate Zpj in the cylindrical coordinate system R, a point Pr of the radial profile Rpj, between the reference point O and the point Pr, where the radial curvature changes the first time of sign from the reference point O towards the point Pj and being located at a distance Dj lower than the distance D_max from the point Pr and having an altitude coordinate Zpj” in the cylindrical coordinate system R, a virtual point Qj being an extrapolation of the part OPj of the radial profile Rpj starting from the point Pj” over the distance Dj, wherein said virtual point Qj has an altitude coordinate ZQ in the cylindrical coordinate system R, |Z • — Z "I characterized in that — -^-7 < 1, preferably lower than 0.8 if the ophthalmic lens has a l^ZQj " ^ZPj"l negative mean optical power at the reference point O and — 7^7 > 1, preferably greater than

I ^ZQj ^{_ Z}Pj"l

I.2 if the ophthalmic lens has a positive mean optical power at the reference point O.

I I. The ophthalmic lens according to one of claim 1 to 8, wherein the first face of the ophthalmic lens is the face of the lens which is the farthest to the eye in worn condition.

12. The ophthalmic lens according to claim 11, wherein the point Pj of the arc A12 having an altitude coordinate Zpj in the cylindrical coordinate system R, a point Pr of the radial profile Rpj, between the reference point O and the point Pr, where the radial curvature changes the first time of sign from the reference point O towards the point Pj and being located at a distance Dj lower than the distance D_max from the point Pr and having an altitude coordinate Zpj” in the cylindrical coordinate system R, a virtual point Qj being an extrapolation of the part O Pr of the radial profile Rpj starting from the point Pr over the distance Dj, wherein said virtual point Qj has an altitude coordinate ZQ, in the cylindrical coordinate system R, characterized in - — > 1, preferably greater than 1.2 if the ophthalmic lens has a negative mean optical l^zQi - ^zpjⁿl power at the reference point 0 and

— < 1, preferably lower than 0.8 if the ophthalmic l^ZQj “ ^ZPj"l lens has a positive mean optical power the reference point O.

13. The ophthalmic lens according to any of claim 1 to 12, wherein the ophthalmic lens is a progressive addition lens and the reference point O is the far vision reference point.

14. The ophthalmic lens according to any of claims 1 to 14, wherein a mean optical power at the reference point O has an absolute value greater than 2 D.

15. The ophthalmic lens according to any of the previous claim, wherein the ophthalmic lens further comprises at least one optical element disposed between the first and second face, wherein said optical elements producing a stopping myopic optical signal towards the wearer eye.

16. Eyewear comprising at least one ophthalmic lens according to one of the previous claims.