Spiral refractive interface with meridians of different optical powers

Abstract

The invention relates to an optical device (100, 200, 400, 800) having an optical axis, comprising at least one surface having at least two meridians, at least a portion of said surface forming, seen from the front, at least one spiral partition, the centre point (206, 406, 806) of said spiral partition being on said optical axis, each spiral partition defining a meridian of different optical power so that the focus obtained extends over a tubular area.

Description

Technical Field

[0001] The present invention relates to the field of optical devices forming refractive interfaces.

[0002] Although described with reference to applications in spectacle lenses, the present invention is applicable to any spherical or toric refractive interface and to any refractive interface having at least two meridians on its surface, which can be used for imaging and / or optical power distribution and / or vision correction.

[0003] Thus, the optical device according to the invention can be an optical lens of an optical system, an ophthalmic lens or a rigid or flexible contact lens, a part of a photographic objective, a part of a motion detector, or a device for concentrating light energy.

[0004] In general, the present invention is applicable to any application in which light (visible or non-visible range) is focused. Background Art

[0005] A lens, such as a spectacle lens, comprises two opposing optical surfaces, known as dioptric interfaces, connected by an edge face, which is typically embedded in a cylinder with a circular base.

[0006] Currently, optical surfaces are generally classified into four different categories, namely:

[0007] - a spherical refractive interface, the surface of which is a part of the inner or outer surface of a sphere;

[0008] - an aspherical refractive interface, which is derived from a spherical surface and whose surface is a portion of a surface of revolution, whose curvature changes continuously from the vertex to the circumferential edge;

[0009] - a toric refractive interface, the surface of which has two orthogonal principal meridians of unequal curvature and whose cross-section along these two meridians is nominally circular;

[0010] A non-toric refractive interface, the surface of which has two mutually perpendicular principal meridians of unequal curvature and at least one of which is not circular in cross section.

[0011] The focus of a spherical lens formed by the association of two spherical refractive interfaces has a single focal length to a point called the imaging focus. This point-by-point focus is characteristic of a so-called "astigmatism-free" optical system.

[0012] refer to Figure 1 , the well-known principle of the astigmatism produced by an optical lens having a toric surface 1 (there is no single point of astigmatism obtained with a spherical lens) will be reviewed.

[0013] The toric surface 1 has a first meridian 2 that curves with a first curvature C1 about the axis of rotation of the annulus (not shown in this figure) such that the first meridian 2 forms an arc of a first circle defined by the outer radius of the annulus.

[0014] The toric surface 1 also has a second meridian 3 perpendicular to the first meridian 1 and curved with a second curvature C2 greater than the first curvature about a center of curvature located on the radius of a circle passing through the middle of the first meridian 2, designated by the reference numeral AA. The axis AA is the optical axis of the toric surface.

[0015] The lens is made of an optical material with a refractive index n, so that light passing through the toric surface 1 undergoes refraction.

[0016] In particular, under parallel illumination, light passing through the first meridian 2 converges at a first focal length 4 , thereby forming a segment 5 parallel to the first meridian 2 , and light passing through the second meridian 3 converges at a second focal length 6 , thereby forming a segment 7 parallel to the second meridian 3 .

[0017] The toric lens 1 has two refractive powers D1 and D2, which are given by the following relationships: D1 = (n-1) C1 and D2 = (n-1) C2.

[0018] US-A-5198844 discloses a multifocal lens divided into a plurality of alternating segments having at least two different refractive powers. In one embodiment, the boundary between consecutive segments is a circular arc starting at the center of the lens. The lens comprises only spherical or aspherical segments, which additionally have surface connections in the form of ridges.

[0019] In general, there is a need to improve so-called spherical astigmatism-free optical devices so as to extend their focal area.

[0020] It is an object of the present invention to at least partially meet this need. Summary of the Invention

[0021] To this end, according to one aspect, the present invention relates to an optical device having an optical axis, comprising at least one surface having at least two meridians, at least a portion of said surface forming at least one spiral partition, seen from the front, said spiral partition having a center point on said optical axis, each spiral partition defining a meridian of different optical power, so that the focus is no longer a simple single point without astigmatism, but extends over a tubular area stretched along the optical axis.

[0022] "From the front" here and in the context of the present invention means a view of the device along the optical axis. In other words, it is a question of a view of the projection onto a plane orthogonal to the optical axis.

[0023] For the sake of clarity, the spiral-shaped surface portion is defined in a projection onto a plane orthogonal to the optical axis.Since the spiral-shaped partition according to the invention is formed on a three-dimensional surface, it is the subject of a spiral.

[0024] The essence of the invention therefore consists in generating a surface comprising at least one spiral subregion, ie a surface having a spiral shape in a projected view onto a plane orthogonal to the optical axis, from a surface of a refractive interface having two or more meridians.

[0025] In other words, the essence of the present invention is to form a spiraled refractive interface comprising a surface having two meridians.

[0026] In some aspects, if a surface having two or more meridians is in an extensible state, what will be done is to twist the surface along one or more helical-shaped curves.

[0027] This spiralization can be applied to any aspheric refractive interface surface with more than two meridians.

[0028] Preferably, the toric surface is helicalized, more preferably an optical device comprising two concentric rings having opposite meridians (ie at 90° to each other) is helicalized.

[0029] In the case of a complex surface, this allows the light to be distributed to a first focal length by the curvature of the first meridian and to a second focal length by the curvature of the second meridian, while the spiraling of the axis of astigmatism has the effect of forming a spiral light focusing tube and therefore has the effect of increasing the focal length of the refractive interface.

[0030] The spiral sectors according to the invention may have different shapes, for example according to a linear law, a quadratic law or a substantially logarithmic law. These various laws may also be combined on the same surface of an optical device, for example to obtain a lens that utilizes a logarithmic law in a first annular sector of the lens and a quadratic law or a linear law in a second annular sector of the lens surrounding the first annular sector.

[0031] The spiral partition according to the present invention can be formed only on a portion of the diopter interface. Therefore, the spiral partition can be formed only in the central portion, only in the connecting portion between two separated surfaces (such as two complex surfaces), or only in the circumferential edge portion.

[0032] The tubular focus obtained according to the invention is a focus that remains the same over an extended range of focal lengths and is inscribed in the tube.

[0033] The present invention has many advantages, among which the following may be mentioned:

[0034] - Used to reduce the need for focusing in any optical imaging system (such as camera objectives, cameras, projector objectives, virtual reality headsets, etc.);

[0035] - The ability to reduce the size of the optical imaging system, for example by eliminating the currently used motorized focusing equipment;

[0036] - its ability to be used in systems for concentrating optical power, such as solar heating systems or laser cutting equipment. For example, in laser cutting equipment, tubular focusing allows the length of the focal zone along the optical axis to be increased and thus the thickness that can be cut to be increased;

[0037] - its ability to be used in optical detection systems (such as infrared motion detectors or physical measurement systems), where the length of the clear area formed by tubular focusing advantageously reduces the need for focusing;

[0038] In vision correction applications, tubular focusing allows for the creation of sharp areas over a long focal length range, for example, to ensure near and far vision with a single spectacle lens, as well as to optically compensate for hyperopia and various ametropias. Thus, a single spectacle lens can be used for more than one ametropia value. Tubular focusing also allows for improved focusing of light rays that deviate from the optical axis, thereby improving the field of vision. This facilitates excellent use in spectacle lenses. Optical lenses, one surface of which has been spiralized according to the present invention, particularly allow for caustics with extended focal lengths.

[0039] Generally, optical devices embodying the present invention may be used in any imaging application (eg, photography, video, optical inspection, vision correction) and any other application requiring focusing.

[0040] Optical devices, especially lenses, can be made of any optical material, such as optical glass or polymers.

[0041] One or more spiral partitions according to the present invention may be produced using machining, additive manufacturing or molding techniques, or a combination of multiple of these techniques.

[0042] According to an advantageous embodiment, the one or more spiral sectors are generated from a complex surface having a first meridian curved with a non-zero first curvature and a second meridian curved with a second curvature strictly greater than the first curvature, the second meridian being perpendicular to the first meridian.

[0043] According to this embodiment and an advantageous variant embodiment, the one or more spiral sectors are generated from a first toric surface and a second toric surface, the first toric surface having a first meridian curved with a first non-zero curvature about the axis of rotation of the first torus and a second meridian curved with a second curvature strictly greater than the first curvature, the second meridian being perpendicular to the first meridian; the second toric surface having a first meridian curved with a first non-zero curvature about the axis of rotation of the second torus and a second meridian curved with a second curvature strictly greater than the first curvature and perpendicular to the first meridian of the second toric surface,

[0044] The first complex surface and the second complex surface each include a plurality of azimuthal sectors around the optical axis,

[0045] a first meridian of the first toric surface and a first meridian of the second toric surface have azimuthal orientations separated by a non-zero angle about the optical axis,

[0046] The spiral partition defines a first optical power meridian and a second optical power meridian resulting from a first meridian of the first toric surface and from a first meridian of the second toric surface.

[0047] According to a variant embodiment, the azimuthal sector of the first complex surface is adjacent to the azimuthal sector of the second complex surface via a spiral partition boundary.

[0048] The first complex surface and the second complex surface may each include two diametrically opposed azimuthal sectors.

[0049] Each angular sector of the first toric surface may be adjacent to two angular sectors of the second toric surface.

[0050] According to an advantageous feature, the angle between the azimuthal orientation of the first meridian of the first toric surface and the azimuthal orientation of the first meridian of the second toric surface is between 60° and 90°.

[0051] Preferably, the first curvature of the first complex surface is equal to the first curvature of the second complex surface.

[0052] More preferably, the second curvature of the first toric surface is equal to the second curvature of the second toric surface.

[0053] According to a variant embodiment, in polar coordinates, the radius of the spiral subarea is related to the angle of the spiral by a linear, quadratic or logarithmic law.

[0054] According to another embodiment, the optical device further comprises a spherical surface centered on the optical axis.

[0055] The optical device according to the invention can advantageously form an optical lens, the front side of which is the surface having at least one spiral subregion.

[0056] A further subject matter of the invention is the use of an optical device as just described for correcting vision and / or for concentrating light power and / or for imaging. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] Other advantages and characteristics of the invention will become more apparent on reading the detailed but non-limiting description of an example of its implementation, given by reference to the following description of the accompanying drawings, in which:

[0058] - Figure 1 is a schematic diagram of the distribution of parallel light beams that have passed through a toric optical lens;

[0059] - Figure 2 is a schematic front view of a first embodiment of a tubular focusing optical lens;

[0060] - Figure 3 is a schematic front view of a multifocal optical lens having two axially opposed toric surfaces;

[0061] - Figure 4 yes Figure 3 A schematic perspective view of a multifocal optical lens;

[0062] - Figure 5 It has been worn Figure 3 and Figure 4 Schematic diagram of the distribution of parallel light beams of an optical lens;

[0063] - Figure 6 is a schematic front view of one embodiment of a multifocal optical lens having two axially opposed toric surfaces;

[0064] - Figure 7 is Figure 6 A schematic front view of an embodiment of a tubular focusing lens according to the present invention resulting from the lens geometry;

[0065] - Figure 8 is a schematic front view of another embodiment of a multifocal optical lens having two axially opposed toric surfaces;

[0066] - Figure 9 is Figure 8 A schematic front view of another embodiment of a tubular focusing lens according to the present invention resulting from the lens geometry;

[0067] - Figure 10is a schematic side view of the distribution of parallel light beams that have passed through the optical lens according to the present invention and compared with a spherical optical lens according to the prior art;

[0068] - Figure 11 is a schematic perspective view of a beam of parallel light rays that has passed through an optical lens having a logarithmic spiral shape according to the present invention, Figure 11 A tubular region showing the focusing of light rays;

[0069] - Figure 12 yes Figure 11 Magnified view of the focusing tube of the light beam and compared with Figure 6 Comparison of focal areas of lenses shown with axially opposed toric surfaces;

[0070] - Figure 13 is a front view of a variant embodiment of a tubular focusing lens according to the present invention, the lens comprising a spherical central portion and a spiral circumferential edge portion;

[0071] - Figure 14 FIG. 1 is a front view of another variant embodiment of a tubular focusing lens according to the present invention, wherein the lens comprises two toric surfaces and a spiral connecting portion between the two toric surfaces. DETAILED DESCRIPTION

[0072] Related to existing technology Figure 1 This has already been reviewed above and will therefore not be described in further detail below.

[0073] The following figures show several examples of optical lenses according to the invention comprising a surface with more than two meridians, said surface having at least one spiral-shaped subregion, producing a focus extending over a tubular area.

[0074] As can be seen from the various figures, the spiral sectors can be generated in various ways, for example according to a linear law, a quadratic law, or a generally logarithmic law. These laws can also be combined in the same lens, for example using a logarithmic law in a first annular sector of the lens and a quadratic law or a linear law in a second annular sector of the lens surrounding the first annular sector.

[0075] A given optical device may include multiple spiral sectors.

[0076] Figure 2 FIG. 8 shows a tubular focusing optical lens 800 according to a first embodiment of the present invention. The diagram used uses contrast to indicate the distinction perpendicular to the plane of the diagram: darker means farther from the reader, and lighter means closer to the reader. Figure 1The optical lens 800 is produced by spiraling the complex surface of the lens shown. The center point is 806. Therefore, the geometry of the surface 801 has a spiral shape, with the center point 806 on the optical axis. In polar coordinates, the angle of the spiral increases with the radial distance from the optical axis. In particular, the first meridian 802 having a first curvature also has a shape that spirals around the optical axis. In addition, the second meridian 802 having a second curvature and parallel to the optical axis has a second curvature. Figure 1 The lines 803 of the second meridian in the toric lens of φ have here different azimuthal orientations, the orientation of these lines changing with the distance from the optical axis due to the helicization.

[0077] In fact, in order to realize the present invention, after analyzing the shortcomings of the multifocal lens in the prior art, the inventors attempted to elongate the focusing area along the optical axis.

[0078] Starting from a multifocal lens having two concentric toric surfaces, the inventors then thought of placing the two toric surfaces axially opposite to each other.

[0079] Figure 3 and Figure 4 Shown are a front view and a perspective view of such a multifocal optical lens 100. The multifocal optical lens 100 includes a first toric surface 102 and a second toric surface 104 concentrically surrounding the first surface 102.

[0080] Thus, if the lens 100 is viewed axially along the optical axis AA, the first surface 102 corresponds to a first optical zone and the second surface 104 corresponds to a second optical zone concentric with the first surface 102 .

[0081] The first toric surface 102 has a first meridian 1021 curved at a first curvature, and a second meridian 1022 curved at a second curvature and perpendicular to the first meridian 1021. Similarly, the second surface 104 has a first meridian 1041 curved at the first curvature, and a second meridian 1042 curved at the second curvature and perpendicular to the first meridian 1041. In particular, on each of the first surface 102 and the second surface 104, the second curvature is greater than the first curvature.

[0082] The peripheral edge of each of the first surface 102 and the second surface 104 has a circular cross-section.

[0083] The first meridian 1021 of the first surface 102 is perpendicular to the first meridian 1041 of the first surface 104 .

[0084] The first curvature of the first surface 102 may be different from or equal to the first curvature of the second surface 104. Likewise, the second curvature of the first surface 102 may be different from or equal to the second curvature of the second surface 104.

[0085] Thus, the lens 100 comprises two concentric rings having different meridian axes, the two rings being in particular arranged opposite or axially opposed, ie such that there is an angle of 90° between the two rings.

[0086] Figure 5 The figure shows the distribution of light that has passed through the multifocal optical lens 100 under parallel illumination in an example in which the first curvature of the first surface is equal to the first curvature of the second surface, and the second curvature of the first surface is equal to the second curvature of the second surface. Light passing through a first meridian 1021 of the first surface 102 converges at a first focal length 106, thereby forming a first segment 1081 parallel to the first meridian 1021, and light passing through a second meridian 1022 of the first surface 102 converges at a second focal length 110, thereby forming a second segment 1082 parallel to the second meridian 1022.

[0087] In addition, light passing through the first meridian 1041 of the second surface 104 converges at the first focal length 106, thereby forming a first segment 1121 parallel to the first meridian 1041, and light passing through the second meridian 1042 of the second surface 104 converges at the second focal length 110, thereby forming a second segment 1122 parallel to the second meridian 1042.

[0088] Thus, with this lens 100, a focal zone is obtained that is longer than the focal zone of prior art multifocal lenses. This elongated focal zone is due to the toricity of the surfaces 102,104.

[0089] Noting that this focusing area was not sufficiently concentrated, the inventors then thought of spiraling the surface in order to obtain a concentrated focus in a tubular area and thereby to obtain a focus over a longer distance along the optical axis.

[0090] Figure 6 and Figure 7 An embodiment of an optical lens 200 is shown that is tubular-focused and has two axially opposed toric surfaces and two helical axially opposed toric surfaces, respectively.

[0091] Figure 6The optical lens 200 includes a first toric surface 202 having a first meridian 2021 curved at a first curvature about the rotation axis of the first torus, and a second meridian curved at a second curvature greater than the first curvature and perpendicular to the first meridian 2021 (represented by an arc 2022 parallel to the second meridian). The optical lens 200 also includes a second toric surface 204, which is juxtaposed with the first toric surface 202 and has a first meridian 2041 curved at the first curvature about the rotation axis of the second torus, and a second meridian curved at the second curvature and perpendicular to the first meridian 2041 (represented by an arc 2042 parallel to the second meridian). Seen from the front, that is, in projection onto a projection plane perpendicular to the optical axis of lens 200 and passing through the center 206 of lens 200, first toric surface 202 corresponds to two diametrically opposed azimuthal sectors 2082 and 2084 that meet at their vertices and turn toward the center 206 of optical lens 200. In the same manner, second toric surface 204 corresponds to two diametrically opposed azimuthal sectors 2081 and 2083 that meet at their vertices and turn toward the center 206. Each azimuthal sector 2082 and 2084 of first toric surface 202 is adjacent to two azimuthal sectors 2081 and 2083 of second toric surface 204. Angular sectors 208 are delimited by the intersection of first toric surface 202 and second toric surface 204, which is the intersection in space between two cylindrical section rings whose axes of rotation are perpendicular. These intersections are represented by the boundaries 2101, 2102, 2103 and 2104 between the azimuthal sectors 2081, 2082, 2083 and 2084. In space, each of the boundaries 2101, 2102, 2103 and 2104 is arranged to recede relative to the first meridians 2021 and 2041 in the direction of the optical axis.

[0092] Figure 7 Shown by Figure 6 2. The optical lens 200 is produced by spiraling the toric surfaces of the lens in FIG. Thus, the first meridian 2021 of the first toric surface 202 and the first meridian 2041 of the second toric surface 204 are spiral partitions, with the center point 206 of the spiral partition being on the optical axis of the optical lens 200. Similarly, each of the boundaries 2101, 2102, 2103, and 2104 is a spiral partition, with the center point 206 of the spiral partition being on the optical axis of the optical lens 200.

[0093] The spiraling can be generated in various ways, for example according to a linear law, a quadratic law or a generally logarithmic law. For the application of the logarithmic law, simplifications must be made near the center 206 of the lens where the spiral angle will be mathematically divergent.

[0094] exist Figure 7 In the example shown, the increasing angle reaches 45° at the peripheral edge 25 of the optical lens 200. This angle can also have other values, for example between 30° and 720°, and in particular equal to 60°. Here, the peripheral edge 25 of the optical lens 200 has a circular shape. This shape can also be non-circular.

[0095] Figure 8 and Figure 9 An embodiment of an optical lens 400 is shown that is tubular-focused and has two axially opposed toric surfaces and two helical axially opposed toric surfaces, respectively.

[0096] Figure 8 The tubular focusing optical lens 400 is designed with Figure 6 The optical lens 200 is similar to the optical lens 200, but has three separate azimuth sectors 401, 402, and 403 instead of four. Azimuth sectors 401, 402, and 403 each have a toric partition, each having a first meridian 4011, 4021, 4031 oriented in a respective azimuth direction. For example, as shown in the figure, first meridians 4011, 4021, 4031 are symmetrically spaced 120° apart. Second meridians are not shown, but each second meridian is perpendicular to the corresponding first meridian. Azimuth sectors 401, 402, and 403 are demarcated by a boundary 405.

[0097] Figure 9 Shown from Figure 8 Lens 400 is a lens that produces a tubular focus by the lens surface in FIG. The spiral divisions here obey the quadratic spiral law: the spiral angle is proportional to the square of the radial distance from the center 406 on the optical axis. Each of the boundaries 405 and each of the first meridians 4011, 4021, and 4031 have the same spiral geometry. In the example shown, the spiral angle reaches 360°, or one full revolution, at the circumferential edge of optical lens 400. A second full revolution, or 720° or greater, can be achieved for larger lenses.

[0098] By way of numerical examples, Figure 9 The tubular focusing optical lens 400 has been realized as a front face having four identical toric branches, whose parameters are as follows:

[0099] - first curvature of the complex surface: focal length equal to 17.4 cm,

[0100] - the second curvature of the complex surface: the focal length is equal to 14 cm,

[0101] -Focuses are spaced 1.4 diopters apart,

[0102] - Spiral shape: logarithm of the golden ratio,

[0103] - Spiral angle: 720°,

[0104] -Lens diameter: 10mm,

[0105] Other geometrical parameters: The back surface is a spherical surface with a radius of curvature of 7.8 mm. The thickness of the lens 400 at the center is equal to 0.5 mm.

[0106] In general, a tubular focusing optical lens according to the present invention can be designed similarly to one of the illustrated optical lenses 200, 400, or 800, using any number of toric surfaces, each occupying an azimuthal sector. Thus, the number of toric branches distributed around the optical axis in the spiral surface can be an even number (e.g., two branches in optical lens 800 and four branches in optical lens 200) or an uneven number (e.g., three branches in optical lens 400). Other numbers of branches are also possible, such as five, six, seven, or more.

[0107] Additionally, the boundaries between adjacent complex surfaces can be steep or gradual. For example, local curvatures can be interpolated near the boundaries to provide a smooth transition region between adjacent complex surfaces and thereby limit excessive slopes.

[0108] By comparing the spherical optical lens 1301 according to the prior art with the tubular focusing optical lens 1302 according to the present invention, Figure 10 The tubular focus obtained according to the invention is shown in FIG, where both lenses 1301, 1302 are designed for vision correction. Figure 10 In , parallel illumination is incident on lenses 1301 and 1302, and Z represents the clear area perceived by the human eye, which is located on either side of the object focus of the lens. Figure 10 It can be clearly seen that the spiral-shaped lens 1302 allows for an elongated sharp zone Z, bounded by an imaginary right cylinder. Thus, the spiralization of the individual optical powers allows for a tubular focusing of the light. In other words, if one of the two dioptric interfaces in the conventional spherical lens 1301 is replaced by the spiral toric surface 1302 according to the present invention, it has the effect of extending the focal zone. The astigmatism-free zone is then no longer a point, but a focusing tube.

[0109] The inventors have performed ray tracing calculations for parallel illumination. Figure 11 The image is shown on one side of the object focus Figure 9 The same lens as the lens in 400. Already in Figure 12 The upper part of FIG. 1 shows the focus area XV in an enlarged manner.

[0110] Figure 12 Also shown are the focal lengths D1 and D2 corresponding to the first and second curvatures of the initial complex surface, respectively. Figure 12 To the right of FIG. 1 , line 1501 shows the size of the focal spot at D1 , and line 1502 shows the size of the focal spot at D2 .

[0111] As a comparison, Figure 12 The lower part shows the Figure 6 The same elements of the axially opposite astigmatic lenses have Figure 11 The initial curvature of the same curvature: line 1511 shows the size of the focal spot at D1, and line 1512 shows the size of the focal spot at D2.

[0112] from Figure 12 It can be clearly seen that the spiralization of the lens according to the invention has the effect of significantly compressing the focal spot between D1 and D2 into the form of an imaginary right cylinder.

[0113] Other variations and advantages of the present invention may be realized without departing from the scope of the invention.

[0114] If, in the example shown, the spiral partition is produced so as to extend exactly across the optical surface of the lens, it is conceivable to carry out the spiraling only on a portion.

[0115] therefore, Figure 13 A variant is shown according to which the optical lens 300 comprises a spherical surface 302 arranged at the centre of the optical surface of the lens 300 , the spiral partitioning being produced only on the circumferential edge of the optical surface.

[0116] Figure 14 A variant is shown according to which an optical lens 100 having two concentric toric surfaces 102 , 104 has a connecting portion 114 forming a helix according to the invention.

[0117] The invention is not limited to the examples that have just been described; in particular, features of the examples shown may be combined in variants that are not shown.

Claims

1. An optical device having an optical axis, comprising at least one surface having at least two meridians, at least a portion of the surface forming at least one spiral partition, the center point (206, 406, 806) of the spiral partition being on the optical axis, each spiral partition defining a meridian of different optical power so that the focus obtained extends over a tubular area, one or more spiral partitions being generated by spiraling a complex surface having a first meridian curved with a non-zero first curvature and a second meridian (2022, 803) curved with a second curvature strictly greater than the first curvature, the second meridian being perpendicular to the first meridian, the spiraling being defined as follows: if the surface having two or more meridians is in an extensible state, what is to be performed is to twist the surface along one or more spiral-shaped curves.

2. The optical device according to claim 1, wherein The one or more spiral partitions are generated by spiraling a first complex surface (202, 401) having a first meridian (2021, 4011) curved around the axis of rotation of the first ring with a non-zero first curvature and a second meridian (2022) curved with a second curvature strictly greater than the first curvature, the second meridian being perpendicular to the first meridian; and the second complex surface (204, 402) having a first meridian (2041, 4021) curved around the axis of rotation of the second ring with a non-zero first curvature and a second meridian (2042) curved with a second curvature strictly greater than the first curvature and perpendicular to the first meridian (2041) of the second complex surface, The first complex surface and the second complex surface respectively include a plurality of azimuthal sectors (2082, 2084; 2081, 2083) around the optical axis, a first meridian (2021, 4011) of the first toric surface (202, 401) and a first meridian (2041, 4021) of the second toric surface (204, 402) having azimuthal orientations separated by a non-zero angle about the optical axis, The spiral partition defines a first optical power meridian (2021, 4011) and a second optical power meridian (2041, 4021) resulting from a first meridian (2021, 4011) of the first complex surface and from a first meridian (2041, 4021) of the second complex surface.

3. The optical device according to claim 2, wherein The azimuthal sector (2082) of the first complex surface is adjacent to the azimuthal sector (2081) of the second complex surface via a spiral partition boundary (210).

4. The optical device according to claim 2, wherein The first complex surface (202, 401) and the second complex surface (204, 402) respectively include two diametrically opposed sectors with azimuthal angles.

5. The optical device according to claim 4, wherein Each angular sector of the first complex surface (202, 401) is adjacent to two angular sectors of the second complex surface (204, 402).

6. The optical device according to claim 2, wherein An angle between the azimuthal orientation of the first meridian of the first complex surface (202, 401) and the azimuthal orientation of the first meridian of the second complex surface (204, 402) is between 60° and 90°.

7. The optical device according to claim 2, wherein: The first curvature of the first complex surface (202, 401) is equal to the first curvature of the second complex surface (204, 402).

8. The optical device according to claim 2, wherein: The second curvature of the first complex surface (202, 401) is equal to the second curvature of the second complex surface (204, 402).

9. The optical device according to claim 1, wherein In polar coordinates, the radius of the spiral partition is related to the angle of the spiral by a linear, quadratic, or logarithmic law.

10. The optical device of claim 1, further comprising a spherical surface (302) centered on the optical axis.

11. The optical device according to claim 1, wherein The optical device forms an optical lens, the front face of which is the surface having at least one spiral-shaped subregion.

12. Use of the optical device according to claim 1 for correcting vision and / or for concentrating light power and / or for imaging.

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