Security element and article with security element

Abstract

The invention relates to the technical field of anti-counterfeiting, and discloses an anti-counterfeiting element which comprises a base material, the surface of the base material is provided with a feature area, and the feature area comprises a plurality of curved surface structures; the curved surface structure has a first direction and a second direction which are parallel to the surface of the base material, the curved surface structure is bent in the first direction, and the bending degree of the curved surface structure in the second direction is smaller than that of the curved surface structure in the first direction. The plurality of curved surface structures are arranged in the characteristic area, and each curved surface structure is bent along the first direction, so that the emergent light of the curved surface structures can be emitted in a fan-shaped direction range under the incident light in the preset direction, the angle distribution of the emergent light is more uniform, and the light emitting efficiency is improved. Therefore, even if a single curved surface structure can obtain a combined effect equivalent to that of a plurality of reflective facets in the prior art, not only can a dynamic effect with higher resolution be realized, but also a finer and more stable appearance pattern can be realized, and the visual angle range is widened.

Description

Technical Field

[0001] The present invention relates to the field of anti-counterfeiting technology, and in particular to an anti-counterfeiting element and an article having the anti-counterfeiting element. Background Art

[0002] In order to prevent counterfeiting through scanning and copying, optical anti-counterfeiting technology is widely used in various high-security or high-value-added printed materials such as banknotes, cards and product packaging, and has achieved very good results.

[0003] The prior art discloses an anti-counterfeiting element, which includes a plurality of reflective facets, and the orientations of different reflective facets are roughly randomly distributed. Under incident light of a predetermined direction, the orientations of the plurality of reflective facets define the direction of the outgoing light, forming a dynamic effect in which the appearance changes with the viewing angle. However, the anti-counterfeiting element needs to use a plurality of reflective facets to form a large area to achieve a uniform distribution of the outgoing light angle, and the combination of the plurality of reflective facets will also reduce the pattern resolution of the dynamic effect. Summary of the invention

[0004] In view of this, the present invention provides an anti-counterfeiting element and an article having the anti-counterfeiting element to solve the problem in the prior art that a single reflective facet of the anti-counterfeiting element cannot achieve uniform distribution of the angle of the emitted light and the pattern resolution of the dynamic effect is low.

[0005] In a first aspect, the present invention provides an anti-counterfeiting element, comprising:

[0006] A substrate, wherein a characteristic region is provided on the surface of the substrate, and the characteristic region includes a plurality of curved surface structures;

[0007] The curved surface structure has a first direction and a second direction parallel to the surface of the substrate. The curved surface structure is curved along the first direction, and the curvature of the curved surface structure along the second direction is smaller than the curvature of the curved surface structure along the first direction.

[0008] Beneficial effect: By arranging multiple curved surface structures in the characteristic area, and each curved surface structure is curved along the first direction, so that under the incident light in a predetermined direction, the emergent light of the curved surface structure can be emitted within a fan-shaped direction range, and the angle distribution of the emergent light is more uniform, that is, a single curved surface structure can obtain a combined effect equivalent to that of multiple reflective small faces in the prior art, which can not only achieve a higher resolution dynamic effect, but also achieve a more uniform angle distribution of the emergent light, achieve a more refined and stable appearance pattern, and improve the viewing angle range.

[0009] In an optional implementation, the degree of curvature of the curved surface structure along the first direction and the second direction is characterized by a slope.

[0010] In an optional implementation, the slope distribution of the curved surface structure along the first direction and the second direction is continuous.

[0011] Beneficial effect: By setting the slope distribution of the curved surface structure along the first direction and the second direction to be continuous, there are no sharp corners on the curved surface structure, the angle of the emitted light is more uniform, the efficiency of the emitted light is higher, and the production quality is higher.

[0012] In an optional implementation, the difference between the slopes of at least two locations of the curved surface structure along the first direction is greater than 0.05.

[0013] Beneficial effect: By setting the difference in the slope of the curved surface structure along the first direction to be larger, the viewing angle of the emitted light can be increased.

[0014] In an optional implementation, the difference between the slopes of at least two locations of the curved surface structure along the first direction is greater than 0.1.

[0015] In an optional implementation, the different curved surface structures have the same slope distribution range along the first direction.

[0016] Beneficial effect: By setting different curved surface structures to have the same slope distribution range along the first direction, the angles of emitted light of each curved surface structure are substantially the same, and the efficiency of emitted light is higher.

[0017] In an optional implementation, cross sections of different curved surface structures along the first direction at least partially overlap.

[0018] In an optional implementation, the cross-sectional shapes of the different curved surface structures along the first direction are the same.

[0019] Beneficial effect: By setting the cross-sectional shapes of different curved surface structures along the first direction to be the same, the production efficiency can be improved.

[0020] In an optional implementation, a cross-section of the curved surface structure along the first direction is convex and / or concave.

[0021] In an optional implementation, a distance between a highest point and a lowest point of a cross section of the curved structure along the first direction is greater than 3 μm.

[0022] Beneficial effect: Since the cross-section of the curved surface structure along the first direction is set to be convex, concave or wavy, by limiting the distance between the highest point and the lowest point of the cross-section of the curved surface structure along the first direction to be greater than 3μm, the distance between the highest point and the lowest point will not be too small, thereby preventing the distance from being too small to produce unexpected diffraction effects.

[0023] In an optional implementation, the average slope of the curved surface structure along the second direction is a predetermined value, and when the observation position is changed along the second direction, the appearance of the observed characteristic region changes with the change of the observation position.

[0024] Beneficial effect: By setting the average slope of the curved surface structure along the second direction to a predetermined value, information of the dynamic effect can be encoded according to the average slope of the curved surface structure along the second direction, so that the curved surface structure can achieve a pre-designed dynamic effect.

[0025] In an optional implementation, the difference in slope of at least a portion of the curved surface structure along the second direction is less than 0.2.

[0026] Beneficial effect: By setting the difference in the slope of at least a part of the area of ​​the curved surface structure along the second direction to be smaller, the viewing angle can be increased and the resolution can be improved.

[0027] In an optional implementation, the difference in slope of at least a portion of the curved surface structure along the second direction is less than 0.05.

[0028] In an optional embodiment, the curved structure is substantially straight along the second direction.

[0029] In an optional implementation, at least some of the plurality of curved surface structures are curved along the second direction.

[0030] In an optional embodiment, the direction perpendicular to the surface of the substrate is the height direction, and the maximum height difference of the curved surface structure along the second direction is smaller than the maximum height difference of the curved surface structure along the first direction.

[0031] In an optional implementation, the length of the curved surface structure along the second direction is less than 20 μm; and / or the length of the curved surface structure along the second direction is greater than 3 μm.

[0032] Beneficial effect: By limiting the length of the curved surface structure along the second direction, it is possible to prevent the curved surface structure from being too long along the second direction. The longer the curved surface structure is, the higher it is, and the more difficult the production process is.

[0033] In an optional embodiment, the direction perpendicular to the surface of the substrate is the height direction, and different curved surface structures have randomly set height differences.

[0034] Beneficial effect: By setting different curved surface structures to have randomly set height differences, the occurrence of unexpected diffraction phenomena can be suppressed.

[0035] In an optional embodiment, the curved surface structure is at least partially covered with a metal layer;

[0036] And / or, the curved surface structure is at least partially covered with a dielectric layer;

[0037] and / or, the curved surface structure is at least partially provided with a secondary microstructure;

[0038] And / or, the difference in refractive index between materials on both sides of the curved structure is greater than 0.1.

[0039] Beneficial effects: By arranging a metal layer and a dielectric layer on the curved surface structure, the reflection effect of the curved surface structure can be enhanced, and the appearance of the curved surface structure changing color with the observation angle can be achieved; by limiting the difference in refractive index of the materials on both sides of the curved surface structure to be greater than 0.1, the refraction effect of the outgoing light can be improved.

[0040] In an optional embodiment, the slope difference of at least part of the curved surface structure along the first direction is between 1.4 times and 2.8 times the maximum average slope of the curved surface structure along the second direction; wherein the slope difference refers to a maximum value of the difference in slopes on a section drawn on a plane parallel to the first direction and the height direction of the curved surface structure, or a section drawn on a plane parallel to the second direction and the height direction of the curved surface structure.

[0041] In an optional embodiment, at least some of the boundaries of the adjacent curved surface structures are curved.

[0042] In an optional implementation, a portion of the boundary of the curved surface structure is arranged according to the contour lines of the curved surface structure.

[0043] In a second aspect, the present invention further provides an article with an anti-counterfeiting element, comprising: the anti-counterfeiting element described above.

[0044] Beneficial effect: Because the article with the anti-counterfeiting element includes the above-mentioned anti-counterfeiting element, it has the same effect as the anti-counterfeiting element, which will not be described in detail here. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0046] Figure 1 A schematic structural diagram of an anti-counterfeiting element according to an embodiment of the present invention;

[0047] Figure 2is a schematic structural diagram of a cross section of the anti-counterfeiting element along a first direction and a height direction;

[0048] Figure 3 It is a schematic structural diagram of the cross section of the anti-counterfeiting element along the second direction and the height direction.

[0049] Description of reference numerals:

[0050] 1-first direction; 2-second direction; 3-height direction; 4-substrate; 5-feature area; 6-curved structure. DETAILED DESCRIPTION

[0051] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0052] Combine the following Figures 1 to 3 , describing an embodiment of the present invention.

[0053] According to an embodiment of the present invention, on the one hand, an anti-counterfeiting element is provided, comprising: a substrate 4, a feature area 5 is provided on the surface of the substrate 4, the feature area 5 comprises a plurality of curved surface structures 6; the curved surface structure 6 has a first direction 1 and a second direction 2 parallel to the surface of the substrate 4, wherein the first direction 1 and the second direction 2 refer to Figure 1 In the direction indicated by the arrow 1 and the direction indicated by the arrow 2, the curved structure 6 is arranged to be curved along the first direction 1, and the degree of curvature of the curved structure 6 along the second direction 2 is less than the degree of curvature of the curved structure 6 along the first direction 1. By arranging a plurality of curved structures 6 in the characteristic region 5, and each curved structure 6 is arranged to be curved along the first direction 1, under incident light in a predetermined direction, the emitted light of the curved structure 6 can be emitted within a fan-shaped direction range, and the angle distribution of the emitted light is more uniform, that is, a single curved structure 6 can obtain a combined effect equivalent to that of a plurality of reflective facets in the prior art, which can not only achieve a higher resolution dynamic effect, but also achieve a more uniform angle distribution of the emitted light, achieve a more refined and stable appearance pattern, and improve the viewing angle range.

[0054] like Figure 1 It is only illustrative that the characteristic region 5 includes 9 curved surface structures 6. In practice, the size of a curved surface structure 6 is at least one order of magnitude smaller than the size of the characteristic region 5. There will be quite a large number of curved surface structures 6 in a characteristic region 5. However, only a small number of curved surface structures 6 are used for illustration, which does not represent actual parameters such as size, proportion and quantity. Figure 2 , Figure 3 Both Figure 1 Similarly, the screenshots are merely exemplary indications of several curved structures 6 and do not represent actual parameters such as size, proportion and quantity.

[0055] In this embodiment, the curvature of the curved structure 6 along the first direction 1 and the second direction 2 is represented by a slope. As a changeable implementation, the curvature of the curved structure 6 along the first direction 1 and the second direction 2 may also be represented by an inclination angle or other methods.

[0056] The slope distribution of the curved surface structure 6 along the first direction 1 and the second direction 2 is continuous. By setting the slope distribution of the curved surface structure 6 along the first direction 1 and the second direction 2 to be continuous, there are no sharp corners on the curved surface structure 6, the angle of the emitted light is more uniform, the efficiency of the emitted light is higher, and the finished product quality of the production is higher.

[0057] To increase the viewing angle of the emitted light, the difference in slope of at least two locations of the curved structure 6 along the first direction 1 is greater than 0.1. As a changeable implementation, the difference in slope of at least two locations of the curved structure 6 along the first direction 1 may be between 0.05 and 0.1.

[0058] In one embodiment, different curved surface structures 6 have the same slope distribution range along the first direction 1. By setting different curved surface structures 6 to have the same slope distribution range along the first direction 1, the angles of emitted light of each curved surface structure 6 are substantially the same, and the efficiency of emitted light is higher. As a convertible implementation, different curved surface structures 6 may also have different slope distribution ranges along the first direction 1, or partially overlapped slope distribution ranges.

[0059] like Figure 2 As shown, the cross-sectional shapes of different curved surface structures 6 along the first direction 1 may be protruding, concave, or both protruding and concave, i.e., wavy. The cross-sectional shapes of different curved surface structures 6 along the first direction 1 may partially overlap, or may not overlap at all. Some may have the same cross-sectional shape, or may have different cross-sectional shapes. The specific cross-sectional shape may be set according to actual needs, and no excessive restrictions are imposed here.

[0060] Since the cross section of the curved structure 6 along the first direction 1 is set to be convex, concave or wavy, the distance between the highest point and the lowest point of the cross section of the curved structure 6 along the first direction 1 can be set to be greater than 3μm. By limiting in this way, the distance between the highest point and the lowest point of the cross section of the curved structure 6 along the first direction 1 will not be too small, so as to prevent the distance from being too small to produce unexpected diffraction effects. Of course, in the specific setting, the distance between the highest point and the lowest point of the cross section of the curved structure 6 along the first direction 1 can be set to 3.5μm, 4μm, 10μm, 40μm, etc., and no excessive limitations are made here.

[0061] The direction perpendicular to the surface of the substrate 4 is the height direction 3, that is, Figure 2 The direction indicated by the arrow 3 in the figure, the height here refers to the depth of the curved surface structure 6, and different curved surface structures 6 have randomly set height differences, which can be referred to as Figure 2 There are random height differences between different curved surface structures 6. The randomly set height difference here refers to some specific values ​​randomly generated by a computer as the height difference. By setting different curved surface structures 6 to have randomly set height differences, it is possible to suppress the occurrence of unexpected diffraction phenomena.

[0062] In order to suppress the occurrence of unexpected diffraction effects, the curved surface structures 6 can be arranged in an irregular grid shape, such as a random grid shape, and different curved surface structures 6 can have different areas and / or different outer contour shapes, etc. In order to suppress the occurrence of unexpected diffraction effects, random height differences are set between different curved surface structures 6.

[0063] In one embodiment, the average slope of the curved structure 6 along the second direction 2 is a predetermined value, and when the observation position is changed along the second direction 2, the appearance of the observed characteristic region 5 changes with the change of the observation position. By setting the average slope of the curved structure 6 along the second direction 2 to a predetermined value, information of the dynamic effect can be encoded according to the average slope of the curved structure 6 along the second direction 2, so that the curved structure 6 achieves a pre-designed dynamic effect.

[0064] The difference in slope of at least a portion of the curved structure 6 along the second direction 2 is less than 0.05. Here, at least a portion of the curved structure 6 along the second direction 2 may be at least 70% of the area. By setting the difference in slope of at least a portion of the curved structure 6 along the second direction 2 to be smaller, the viewing angle and the resolution can be increased. As a convertible embodiment, the difference in slope of at least a portion of the curved structure 6 along the second direction 2 may be between 0.05 and 0.2.

[0065] Specific as Figure 3As shown, the curved surface structure 6 is substantially straight along the second direction 2. At this time, when the observation position is changed along the first direction 1 of the curved surface structure 6, the degree to which the appearance of the observed characteristic region 5 changes with the change of the observation position is less than the degree to which the appearance of the observed characteristic region 5 changes with the change of the observation position when the observation position is changed along the second direction 2 of the curved surface structure 6. At this time, the resolution of the curved surface structure 6 is the highest, and the dynamic effect of the observable characteristic region 5 is the best.

[0066] As a convertible implementation, at least some of the multiple curved structures 6 may be curved along the second direction 2. Since the contour lines of the curved structures 6 are curved, the boundaries of the curved structures 6 may be curved in the shape of the contour lines, which helps to reduce the height difference at the boundaries.

[0067] The direction perpendicular to the surface of the substrate 4 is the height direction 3, and the maximum height difference of the curved structure 6 along the second direction 2 is smaller than the maximum height difference of the curved structure 6 along the first direction 1, that is, the degree of curvature of the curved structure 6 along the second direction 2 is smaller than the degree of curvature of the curved structure 6 along the first direction 1.

[0068] Specifically, the length of the curved structure 6 along the second direction 2 is greater than 3 μm and less than 20 μm. By limiting the length of the curved structure 6 along the second direction 2, it is possible to prevent the curved structure 6 from being too long along the second direction 2. The longer the curved structure 6 is, the higher it is, and the more difficult the production process is. As a convertible implementation, it is also possible that the length of the curved structure 6 along the second direction 2 is between other data ranges, and no excessive restrictions are made here.

[0069] In one embodiment, the curved surface structure 6 is covered with a metal layer and a dielectric layer, which can enhance the reflective effect of the curved surface structure 6. Specifically, the curved surface structure 6 can be at least partially covered with a metal-dielectric-metal three-layer structure, and the metal-dielectric-metal three-layer structure can achieve an appearance that changes color with the observation angle, such as an aluminum-silicon dioxide-chromium three-layer structure, or a dielectric-metal-dielectric three-layer structure, a multi-layer dielectric structure, etc. can also achieve similar appearance effects. As a convertible implementation, the curved surface structure 6 can also be covered with only a metal layer, or only a dielectric layer. As a convertible implementation, the curved surface structure 6 can also be covered with a metal layer, a dielectric layer, or both a metal layer and a dielectric layer on only a part of the structure.

[0070] In one embodiment, at least part of the curved structure 6 is provided with a secondary microstructure, such as a one-dimensional or two-dimensional grating with a period less than 450 nanometers. By providing the secondary microstructure, the color of the reflected light can be modulated to achieve an appearance effect of at least two colors at a fixed observation angle.

[0071] In one embodiment, the difference in refractive index of the materials on both sides of the curved structure 6 is greater than 0.1. Since the two sides of the curved structure 6 need to have a difference in refractive index to achieve the refraction effect of light, the materials on both sides of the curved structure 6 here may refer to one side of the curved structure 6 exposed to the air, generally the interface between the air and the resin material has a large difference in refractive index, or the refractive index of the resin materials on both sides of the curved structure 6 is different. By limiting the difference in refractive index of the materials on both sides of the curved structure 6 to be greater than 0.1, the refraction effect of the emitted light can be improved.

[0072] In order to extend the life of the anti-counterfeiting element, a protective glue or a composite protective film may also be coated on the curved surface structure 6 .

[0073] In one embodiment, the slope difference of at least part of the curved surface structure 6 along the first direction 1 is between 1.4 and 2.8 times the maximum average slope of the curved surface structure 6 along the second direction 2. The slope difference refers to the maximum value of the difference in slopes on a section line drawn on a plane parallel to the first direction 1 and the height direction 3 of the curved surface structure 6, or on a plane parallel to the second direction 2 and the height direction 3 of the curved surface structure 6. The slope difference of the section line refers to the difference in slopes between the two places on the section line where the slopes differ the most. The greater the slope difference, the greater the degree of curvature.

[0074] By setting the slope difference of the curved surface structure 6 along the first direction 1 to be between 1.4 and 2.8 times the maximum average slope of the curved surface structure 6 along the second direction 2, the consistency of the observable angle can be achieved. Since the maximum values ​​of the slopes of the curved surface structure 6 in the first direction 1 and the second direction 2 should be approximately the same, and the slope distribution of a single curved surface structure 6 in the first direction 1 is approximately symmetrical, the maximum value of the slope of a single curved surface structure 6 in the first direction 1 is half of the slope difference of the single curved surface structure 6; different curved surface structures 6 have different slopes in the second direction 2, and the maximum value of the slope in the second direction 2 is the slope of the curved surface structure 6 with the largest average slope in the second direction 2. Therefore, in the most ideal case, the slope difference of the curved surface structure 6 in the first direction 1 is twice the maximum average slope of the curved surface in the second direction 2. As a convertible embodiment, the slope difference of the curved surface along the first direction 1 may also be 1.4 times, 1.5 times, 2.5 times, or 2.8 times the maximum average slope of the curved surface structure 6 in the second direction 2.

[0075] In one embodiment, at least some of the borders of the adjacent curved structures 6 are arranged in a curved manner, which is conducive to reducing the height fluctuation on the borders, reducing the total height of the curved structure 6, and then reducing the difficulty of production. Specifically, some of the borders of the curved structure 6 are arranged according to the contour lines of the curved structure 6. Since the borders of the curved structure 6 are arranged in a curved manner, the curved structure 6 is arranged according to the contour lines of the curved structure 6 at the borders, so that the edges of the curved structure 6 at the borders are of the same height, and this arrangement can avoid the height fluctuation at some edges of the curved structure 6.

[0076] The anti-counterfeiting element disclosed in this embodiment has the advantages of high resolution and uniform distribution of the angle of the emitted light. This embodiment improves the viewing angle range by customizing the morphology of the curved surface structure 6. A single curved surface structure 6 can achieve the combined effect of multiple randomly oriented optical facets in the prior art, which can not only achieve a higher resolution dynamic effect, but also achieve a more uniform distribution of the angle of the emitted light, and achieve a more refined and stable appearance pattern.

[0077] The anti-counterfeiting element disclosed in this embodiment is more difficult to forge. The curved surface structure 6 with customized morphology has a higher degree of freedom and requires more parameters to describe a single curved surface structure 6. These parameters are difficult to measure and even more difficult to be copied and forged by counterfeiters.

[0078] According to an embodiment of the present invention, on the other hand, there is provided an article with an anti-counterfeiting element, comprising: the anti-counterfeiting element mentioned above.

[0079] The article with anti-counterfeiting element in the present embodiment is a banknote. As a convertible embodiment, it can also be that the article with anti-counterfeiting element is anti-counterfeiting paper, or an identity card or other valuable documents, such as chip cards, checks, receipts, contracts, credit cards, etc.

[0080] Part of the structure of the anti-counterfeiting element can be embedded in the banknote, and part of the structure can be exposed. As a convertible embodiment, the anti-counterfeiting element can be hot-stamped on the surface of the banknote by pre-coating hot melt adhesive, or the anti-counterfeiting element can be pasted on the surface of the banknote.

[0081] The anti-counterfeiting element can specifically be a security thread, a sealing tape, a security tape, a security strip, a patch, a label, etc., so as to be applied to items such as security paper and valuable documents.

[0082] Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations are all within the scope defined by the appended claims.

Claims

1. An anti-counterfeiting element, characterized in that: include: A substrate (4), wherein a characteristic region (5) is provided on the surface of the substrate (4), and the characteristic region (5) includes a plurality of curved surface structures (6); The curved surface structure (6) has a first direction (1) and a second direction (2) parallel to the surface of the substrate (4); the curved surface structure (6) is arranged in a curved manner along the first direction (1); and the degree of curvature of the curved surface structure (6) along the second direction (2) is smaller than the degree of curvature of the curved surface structure (6) along the first direction (1).

2. The anti-counterfeiting element according to claim 1, characterized in that: The degree of curvature of the curved surface structure (6) along the first direction (1) and the second direction (2) is characterized by a slope.

3. The anti-counterfeiting element according to claim 2, characterized in that: The slope distribution of the curved surface structure (6) along the first direction (1) and the second direction (2) is continuous.

4. The anti-counterfeiting element according to claim 2, characterized in that: The difference between the slopes of at least two locations of the curved surface structure (6) along the first direction (1) is greater than 0.

05.

5. The anti-counterfeiting element according to claim 4, characterized in that: The difference between the slopes of at least two locations of the curved surface structure (6) along the first direction (1) is greater than 0.

1.

6. The anti-counterfeiting element according to claim 2, characterized in that: The different curved surface structures (6) have the same slope distribution range along the first direction (1).

7. The anti-counterfeiting element according to claim 1, characterized in that: The cross sections of the different curved surface structures (6) along the first direction (1) at least partially overlap.

8. The anti-counterfeiting element according to claim 7, characterized in that: The cross-sectional shapes of the different curved surface structures (6) along the first direction (1) are the same.

9. The anti-counterfeiting element according to claim 8, characterized in that: The cross-section of the curved surface structure (6) along the first direction (1) is convex and / or concave.

10. The anti-counterfeiting element according to claim 8, characterized in that: The distance between the highest point and the lowest point of the cross section of the curved surface structure (6) along the first direction (1) is greater than 3 μm.

11. The anti-counterfeiting element according to any one of claims 1 to 10, characterized in that: The average slope of the curved surface structure (6) along the second direction (2) is a predetermined value, and when the observation position is changed along the second direction (2), the appearance of the observed characteristic area (5) changes with the change of the observation position.

12. The anti-counterfeiting element according to claim 11, characterized in that: The difference in slope of at least a portion of the curved surface structure (6) along the second direction (2) is less than 0.

2.

13. The anti-counterfeiting element according to claim 12, characterized in that: The difference in slope of at least a portion of the curved surface structure (6) along the second direction (2) is less than 0.

05.

14. The anti-counterfeiting element according to claim 13, characterized in that: The curved structure (6) is substantially straight along the second direction (2).

15. The anti-counterfeiting element according to any one of claims 1 to 10, characterized in that: At least some of the curved surface structures (6) among the plurality of curved surface structures (6) are arranged in a curved manner along the second direction (2).

16. The anti-counterfeiting element according to claim 15, characterized in that: The direction perpendicular to the surface of the substrate (4) is the height direction (3), and the maximum height difference of the curved surface structure (6) along the second direction (2) is smaller than the maximum height difference of the curved surface structure (6) along the first direction (1).

17. The anti-counterfeiting element according to any one of claims 1 to 10, characterized in that: The length of the curved surface structure (6) along the second direction (2) is less than 20 μm; and / or the length of the curved surface structure (6) along the second direction (2) is greater than 3 μm.

18. The anti-counterfeiting element according to any one of claims 1 to 10, characterized in that: The direction perpendicular to the surface of the substrate (4) is the height direction (3), and the different curved surface structures (6) have randomly set height differences.

19. The anti-counterfeiting element according to any one of claims 1 to 10, characterized in that: The curved surface structure (6) is at least partially covered with a metal layer; And / or, the curved surface structure (6) is at least partially covered with a dielectric layer; And / or, the curved surface structure (6) is at least partially provided with a secondary microstructure; And / or, the difference in refractive index between materials on both sides of the curved structure (6) is greater than 0.

1.

20. The anti-counterfeiting element according to any one of claims 1 to 10, characterized in that: The slope difference of at least part of the curved surface structure (6) along the first direction (1) is between 1.4 and 2.8 times the maximum average slope of the curved surface structure (6) along the second direction (2); wherein the slope difference refers to the maximum value of the difference in slopes on a section drawn on a plane parallel to the first direction (1) and the height direction (3) of the curved surface structure (6), or on a section drawn on a plane parallel to the second direction (2) and the height direction (3) of the curved surface structure (6).

21. The anti-counterfeiting element according to any one of claims 1 to 10, characterized in that: At least some of the boundaries of the adjacent curved surface structures (6) are arranged in a curved manner.

22. The anti-counterfeiting element according to claim 21, characterized in that: Part of the boundary of the curved surface structure (6) is arranged according to the contour lines of the curved surface structure (6).

23. An article having an anti-counterfeiting element, characterized in that: include: The security element according to any one of claims 1 to 22.

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