阅读说明：本技术 可双面观察的光学防伪元件 (Optical anti-counterfeiting element capable of being observed from two sides ) 是由 胡春华 朱军 周赟 封敏宇 于 2019-09-29 设计创作，主要内容包括：本发明公开了一种光学防伪元件及其制造方法,属于光学防伪技术领域。所述光学防伪元件包括：第一起伏结构层；所述第一起伏结构层包括具有第一微结构的第一区域和具有第二微结构的第二区域,所述第一微结构的比体积小于所述第二微结构的比体积；所述第一起伏结构层一侧有依次层叠的第一镀层、第二起伏结构层和第二镀层；所述第一镀层和所述第二镀层均位于所述第一区域而不位于所述第二区域,且所述第一镀层和所述第二镀层至少局部具有不同的表面起伏形状。(The invention discloses an optical anti-counterfeiting element and a manufacturing method thereof, belonging to the technical field of optical anti-counterfeiting. The optical security element comprises: a first photovoltaic structure layer; the first photovoltaic structure layer comprises a first region with a first microstructure and a second region with a second microstructure, and the specific volume of the first microstructure is smaller than that of the second microstructure; a first coating, a second undulating structure layer and a second coating which are sequentially stacked are arranged on one side of the first undulating structure layer; the first and second plating layers are both located in the first region and not in the second region, and the first and second plating layers have different surface relief shapes at least in part.)

1. A thin-film optical security element, comprising:

a first photovoltaic structure layer (2);

the first photovoltaic structure layer (2) comprises a first region (A) with a first microstructure and a second region (B) with a second microstructure, the specific volume of the first microstructure is smaller than that of the second microstructure;

a first plating layer (3), a second undulating structure layer (4) and a second plating layer (5) which are sequentially stacked are arranged on one side of the first undulating structure layer (2);

the first and second coating layers (3, 5) are located in the first region (A) but not in the second region (B), and the first and second coating layers (3, 5) have different surface relief shapes at least in part.

2. A thin-film optical security element according to claim 1,

the surface relief of the second plating layer (5) is flat or substantially flat.

3. A thin-film optical security element according to claim 1,

the materials of the first plating layer (3) and the second plating layer (5) are selected from different materials.

4. A thin-film optical security element according to claim 1,

one of the first plating layer (3) and the second plating layer (5) is a single-layer metal plating layer, and the other is a multi-layer interference light variable plating layer.

5. A thin-film optical security element according to claim 1,

the first plating layer (3), the second fluctuating structure layer (4) and the second plating layer (5) form a multilayer interference light variable plating layer, wherein the thin-film optical anti-counterfeiting element has interference light variable characteristics on any side of the multilayer interference light variable plating layer.

6. A thin-film optical security element according to claim 1,

the second coating (5) is also adjoined by a protective layer (6), the projection of which protective layer (6) is located in the first region (A).

7. A method for producing an optical security element, the method comprising:

s1) forming a first photovoltaic structure layer, wherein the first photovoltaic structure layer comprises a first region having a first microstructure and a second region having a second microstructure, and the specific volume of the first microstructure is smaller than that of the second microstructure;

s2) sequentially forming a first plating material layer, a second undulation structure layer, a second plating material layer and a protective layer material layer on one side of the first undulation structure layer;

s3) placing the semi-finished product formed in the step S2) in a corrosive atmosphere capable of reacting with the first plating material layer until the partial plating material layer of the first plating material layer and the second plating material layer in the second area is completely or partially removed, and leaving at least the first plating layer and the second plating layer stacked only in the first area, wherein the first plating layer and the second plating layer are the partial plating material layer of the first plating material layer and the second plating material layer in the first area which are not removed.

8. A method of manufacturing an optical security element according to claim 7,

and step S2), after the second relief structure layer is formed, printing the part of the second relief structure layer in the first area by a printing process, and forming a second relief structure layer after printing.

9. A method of manufacturing an optical security element according to claim 8,

step S2), after forming the second relief structure layer, the second relief structure layer has a flat or substantially flat structure.

10. A method of manufacturing an optical security element according to claim 8,

after the second relief structure layer is formed in step S2), the surface structure of the second relief structure layer having the same projection position has the same lateral distribution as the surface structure of the first relief structure layer, and the surface structure of the second relief structure layer is flatter than the surface structure of the first relief structure layer.

11. A method of manufacturing an optical security element according to claim 8,

step S2), after forming the second relief structure layer, performing embossing to form a microstructure significantly different from the first microstructure or the second microstructure.

Technical Field

The invention relates to the technical field of optical anti-counterfeiting, in particular to a thin-film optical anti-counterfeiting element and a manufacturing method of the optical anti-counterfeiting element.

Background

In order to prevent counterfeiting by means of scanning, copying and the like, optical anti-counterfeiting technology is widely adopted in various high-security or high-added-value printed matters such as bank notes, valuable papers and the like, and a very good effect is achieved. Generally, in the optical anti-counterfeiting technology, anti-counterfeiting elements such as thin-film security threads, labels or wide strips are used as carriers to achieve the anti-counterfeiting purpose.

To increase the brightness, the security image on the optical security element is typically provided with a metallic reflective layer. The metal reflecting layer is partially removed, so that a specific hollow pattern is formed during light transmission observation, and the visual effect and the anti-counterfeiting capacity of the optical anti-counterfeiting element can be greatly improved. In order to further improve the anti-counterfeiting effect, the anti-counterfeiting elements in the high-security or high-value-added printed matter have visible parts on both sides of the printed matter, such as window anti-counterfeiting wide strips or double-sided windowing security lines on bank notes of some countries. If the new edition is 5 pound anti-fake wide strip, the front side observation and the back side observation of the hollow holographic turret image in the window part respectively show golden and silver characteristics. And as for the new edition of anti-counterfeiting wide strips with 20 Euro, the front observation and the back observation of the hollow Europa image of the window part respectively have different rainbow holographic effects, and the outlines of the two holographic images are completely corresponding. However, in the above two products, the alignment relationship between the holographic image and the hollow area is not strict, i.e. there is no specific alignment relationship.

It is envisaged that the visual effect and security of the optical security element can be further enhanced if images having different optical microstructures (e.g. holograms) are viewed on either side of the security element and at least one of the microstructures is formed in close register with the hollowed-out region.

Disclosure of Invention

The invention aims to provide a double-sided observable optical anti-counterfeiting element capable of improving visual effect and anti-counterfeiting capacity and a manufacturing method thereof, and is particularly suitable for being applied to protected products with window structures.

In order to achieve the above object, an embodiment of the present invention provides a thin-film optical security element, including: a first photovoltaic structure layer; the first photovoltaic structure layer comprises a first region with a first microstructure and a second region with a second microstructure, and the specific volume of the first microstructure is smaller than that of the second microstructure; a first coating, a second undulating structure layer and a second coating which are sequentially stacked are arranged on one side of the first undulating structure layer; the first and second plating layers are both located in the first region and not in the second region, and the first and second plating layers have different surface relief shapes at least in part.

The specific volume of the microstructure mentioned here means the ratio of the volume of liquid that is supposed to just completely cover the surface of the relief structure to the projected area of the surface of the relief structure on the horizontal plane, when the relief structure layer is placed in a horizontal state; by this definition, the dimension of specific volume is um³/um²(ii) a By this definition, flat structures are considered to be microstructures with a zero specific volume; the purpose of setting the difference of the specific volumes of the first microstructure and the second microstructure is to obtain the hollowing of the plating layer of the second area, namely the first plating layer and the second plating layer are strictly positioned in the first area but not positioned in the second area; the principle of realizing the plated layer hollowing will be described in detail in the detailed description; thus, the microstructure forms an image that is exactly registered with the hollowed-out area.

Optionally, the surface relief shape of the second plating layer is flat or substantially flat.

Preferably, the materials of the first and second plating layers are selected from different materials. In particular, one of the first plating layer and the second plating layer is a single-layer metal plating layer, and the other is a multi-layer interference light variable plating layer.

Preferably, the first plating layer, the second relief structure layer and the second plating layer form a multilayer interference light variable plating layer, wherein the thin-film optical anti-counterfeiting element has an interference light variable characteristic on any side of the multilayer interference light variable plating layer.

Optionally, the second plating layer is further adjoined with a protective layer, and a projection of the protective layer is located in the first region.

The embodiment of the invention also provides a manufacturing method of the optical anti-counterfeiting element, which is characterized by comprising the following steps:

s1) forming a first photovoltaic structure layer, wherein the first photovoltaic structure layer comprises a first region having a first microstructure and a second region having a second microstructure, and the specific volume of the first microstructure is smaller than that of the second microstructure;

s2) sequentially forming a first plating material layer, a second undulation structure layer, a second plating material layer and a protective layer material layer on one side of the first undulation structure layer;

s3) placing the semi-finished product formed in the step S2) in a corrosive atmosphere capable of reacting with the first plating material layer until the partial plating material layer of the first plating material layer and the second plating material layer in the second area is completely or partially removed, and leaving at least the first plating layer and the second plating layer stacked only in the first area, wherein the first plating layer and the second plating layer are the partial plating material layer of the first plating material layer and the second plating material layer in the first area which are not removed.

Preferably, after the second layer of relief structure layer is formed in step S2), a printing process is further used to print (or called coating) a portion of the second layer of relief structure layer located in the first region, and the second layer of relief structure is formed after printing. Further preferably, after forming the second relief structure layer in step S2), the second relief structure layer has a flat or substantially flat structure; or, after forming the second relief structure layer in step S2), the surface structure of the second relief structure layer with the same projection position has the same lateral distribution as the surface structure of the first relief structure layer, and the surface structure of the second relief structure layer is flatter than the surface structure of the first relief structure layer; alternatively, in step S2), after forming the second relief structure layer, embossing is performed to form a microstructure significantly different from the first microstructure or the second microstructure.

Through the technical scheme, the optical anti-counterfeiting element capable of improving the visual effect and the anti-counterfeiting capacity can be obtained, namely, images formed by optical microstructures of the first relief structure layer and the second relief structure layer are respectively arranged in the first area when the two sides of the anti-counterfeiting element are observed, and the images formed by the microstructures of the first relief structure layer (namely the first area) are strictly aligned with the hollowed-out area (namely the second area).

Additional features and advantages of embodiments of the invention will be set forth in the detailed description which follows.

Drawings

The accompanying drawings, which are included to provide a further understanding of the embodiments of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the embodiments of the invention without limiting the embodiments of the invention. In the drawings:

FIG. 1 is a schematic contrast view of different optical effects viewed from different sides of an exemplary optical security element according to embodiments of the present invention;

FIG. 2 is a cross-sectional view of an exemplary optical security element along the X-X mark direction in accordance with an embodiment of the present invention;

FIG. 3 is a cross-sectional view of an exemplary optical security element after a first relief structure layer has been formed on a substrate during fabrication of the optical security element according to an embodiment of the present invention;

FIG. 4 is a cross-sectional view of an exemplary optical security element after a first layer of plating material is formed on a first underlying structural layer during fabrication of the optical security element according to an embodiment of the present invention;

FIG. 5 is a cross-sectional view of an exemplary optical security element after a second layer of relief structure material is formed over the first layer of plating material during fabrication of the optical security element according to an embodiment of the present invention;

FIG. 6 is a cross-sectional view of an exemplary element having a second layer of plating material formed over a second layer of relief structure material during fabrication of an optical security element in accordance with an embodiment of the present invention;

FIG. 7 is a cross-sectional view of an exemplary optical security element after a protective layer material layer is formed on a second plating material layer during fabrication of the optical security element according to an embodiment of the present invention;

fig. 8 is a cross-sectional view of an exemplary optical anti-counterfeiting element after etching a semi-finished product in a corrosive atmosphere during manufacturing of the optical anti-counterfeiting element according to an embodiment of the present invention.

Description of the reference numerals

1 substrate 2 first photovoltaic structural layer

3 first coating 4 second relief structure layer

5 second plating layer 6 protective layer

7 other functional coating

Detailed Description

The following detailed description of embodiments of the invention refers to the accompanying drawings. It should be understood that the detailed description and specific examples, while indicating embodiments of the invention, are given by way of illustration and explanation only, not limitation.

Fig. 1 shows a schematic comparison of the effect of an optical security element according to an embodiment of the present invention on the first side and the second side. Fig. 2 is a possible cross-sectional view along the line X-X of the optical element shown in fig. 1. As shown in fig. 1, an image formed by a specific optical microstructure (for example, a letter "PY" having a three-dimensional relief effect as shown in part (a) of fig. 1) can be observed at the first side, a transparent hollowed-out region is formed around the image, and the hollowed-out region precisely extends along the edge of the image. Viewed from the second side, within the outline formed by the first side image, another optical effect (e.g., a rainbow hologram effect appearing within the outline of the letter "PY" as shown in part (b) of fig. 1) different from the first side optical microstructure can be seen, and this optical effect is not in a positionally strict alignment with the hollowed-out region. The optical element has good visual effect and anti-counterfeiting capability by observing images with different optical microstructures on two sides, wherein the optical images formed by the microstructures on the first side are strictly aligned with the hollow areas.

Structurally, as shown in fig. 2, the optical security element at least includes: a first photovoltaic structure layer 2, wherein the first photovoltaic structure layer 2 at least comprises a first area A consisting of a first microstructure and a second area B consisting of a second microstructure, and the specific volume of the first microstructure is smaller than that of the second microstructure; a first plating layer 3 of the same type located in the first region A and covering the first photovoltaic structure layer 2; a second relief structure layer 4, the surface shape of the second relief structure layer 4 being different from the surface shape of the first relief structure layer 2; the same type of second plating layer 5 located in the first area a covers the second relief structure layer 4. The first plating layer 3 located in the first region a exhibits a letter "PY" having a three-dimensional relief effect when viewed from a first side (below), and the second plating layer 5 located in the first region a exhibits a rainbow hologram characteristic outlined by the letter "PY" when viewed from a second side (above). Generally, the first plating layer 3 and the second plating layer 5 are selected from the same plating material. For example, the first plating layer 3 and the second plating layer 5 are both aluminum layers. The first coating layer 3 and the second coating layer 5 can also be made of different coating materials in order to further increase the coating characteristics introduced by the difference between the coating layers on both sides. For example, if the first plating layer 3 is an aluminum layer and the second plating layer 5 is a copper layer, the first side is observed as a silver feature and the second side is observed as a red feature. For another example, if the first plating layer 3 is an aluminum layer and the second plating layer 5 is a multilayer interference light variation plating layer, the first side is observed as a silver-colored feature, and the second side is observed as an interference light variation feature, that is, the image appears different colors according to the observation angle. For another example, the first plating layer 3, the second relief structure layer 4, and the second plating layer 5 themselves constitute a set of multi-layer interference light-variable plating layers, and if the first plating layer 3, the second relief structure layer 4, and the second plating layer 5 are respectively used as a reflection layer, a dielectric layer, and an absorption layer of the multi-layer light-variable plating layers, the first side is observed as a single-layer plating layer characteristic presented by the reflection layer itself, and the second side is observed as an interference light-variable characteristic. The optical security element may further comprise: a substrate 1 to provide support for other materials; the protective layer 6 is used for protecting the plating layer of the first area A in the hollowing-out process; other functional coatings 7 to perform other auxiliary functions, such as adhesion to the product to be protected.

The following describes in detail a manufacturing process of manufacturing the optical security element shown in fig. 2 according to the manufacturing method of the embodiment of the present invention with reference to fig. 3 to 8. For the sake of brevity, the first plating layer 3 is selected as a single metal plating layer, and the second plating layer 5 is selected as a multi-layer interference light variation plating layer.

S1, forming a first photovoltaic structure layer 2 on the surface of the substrate 1, where the first photovoltaic structure layer 2 at least includes a first region a composed of a first microstructure and a second region B composed of a second microstructure, and a specific volume of the first microstructure is smaller than that of the second microstructure, as shown in fig. 3.

The substrate 1 may be at least partially transparent, or may be a colored dielectric layer, or may be a transparent dielectric film with a functional coating on the surface, or may be a multilayer film formed by compounding. The substrate 1 is generally formed of a film material having good chemical resistance and high mechanical strength, and for example, the substrate 1 may be formed of a plastic film such as a polyethylene terephthalate (PET) film, a polyethylene naphthalate (PEN) film, or a polypropylene (PP) film, and the substrate 1 is preferably formed of a PET material. The substrate 1 may contain an adhesion-enhancing layer to enhance the adhesion of the substrate 1 to the relief structure layer 2. The substrate 1 may also contain a release layer to effect separation of the final product substrate 1 from the relief structure layer 2.

The relief structure layer 2 can be formed by mass replication through processing methods such as ultraviolet casting, die pressing, nano-imprinting and the like. For example, the relief structure layer 2 may be formed of a thermoplastic resin by a molding process, in which the thermoplastic resin printed in advance on the base material 1 is heated and softened and deformed while passing through a metal mold at a high temperature, thereby forming a specific relief structure, and then cooled and formed. The relief structure layer 2 may be formed by a radiation-curing casting process in which a radiation-curable resin is printed on the base material 1, the material is cured by irradiating ultraviolet rays or electron beams while pressing the original plate thereon, and the original plate is removed to form the relief structure layer 2.

In order to meet the requirement of subsequent hollowing, the specific volume of the second microstructure is larger than that of the first microstructure. Preferably, the specific volume of the first microstructure is greater than or equal to 0um³/um²Less than 0.5um³/um²The specific volume of the second microstructure is more than 0.4um³/um²Is less than 3um³/um². The first microstructure and the second microstructure can be one or a combination of a periodic structure or a non-periodic structure, and the structure is one or a combination of a sine structure, a rectangular grating structure, a trapezoidal grating structure, a blazed grating structure and an arc grating structure. The size and lateral arrangement of the first microstructures is determined by the desired optical effect. The first microstructure may also be selected from planar structures. Generally, the second microstructure is only required for hollowing out, and does not provide additional optical effect, so that the structure can be simplified, for example, an isosceles triangle (with a cross section of 10um at the bottom and 4um at the top) with one-dimensional arrangement (i.e. a specific volume of 2 um)³/um²) A blazed grating of (1).

S2, a material layer (first plating material layer) for obtaining the first plating layers 3 is formed on the relief structure layer 2, as shown in fig. 4.

In this embodiment, the first plating layer 3 is selected to be a single metal reflective plating layer. The metal reflective coating serves to enhance the brightness of the optical effect formed by the microstructures. The material of the metal reflective coating can be a mixture or alloy of one metal, at least two of Al, Cu, Ni, Cr, Ag, Fe, Sn, Au, Pt and the like, and is preferably aluminum because aluminum has low cost and high brightness and is easy to remove by reaction with acid solution and alkali solution. The thickness of the metallic reflective coating is generally chosen to be greater than 10nm and less than 80nm, preferably greater than 20nm and less than 50 nm. If the metal reflective coating is too thin, the brightness is insufficient; if the metal reflective coating is too thick, the fastness to the relief structure layer is poor, and the cost is increased.

The first coating layer 3 may typically be formed on the relief structure layer 2 by physical and/or chemical vapour deposition methods, including but not limited to thermal evaporation, magnetron sputtering, MOCVD, etc. Preferably, the first plating layer 3 is formed on the relief structure layer 2 in a conformal coverage with a uniform surface density.

S3, a material layer for obtaining the second relief structure layer 4 (second relief structure layer) is formed, as shown in fig. 5.

The surface shape of the second relief structure layer 4 in the first region a is different from the surface shape of the first relief structure layer 2 at least in partial regions. Various methods are possible for this purpose. For example, first, the amount of printing of the second relief structure layer 4 is chosen to be such that, after printing of the second relief structure layer 4, natural levelling forms a flat or substantially flat structure in the first area a; secondly, the amount of printing of the second relief structure layer 4 is chosen to be such that, after the printing of the second relief structure layer 4, the surface structure naturally formed in the first area a has the same lateral distribution as the surface structure of the first relief structure layer 2 in the corresponding position (for example in the same projection on the substrate 1), but is more planarized than the latter; thirdly, after the second relief structure layer 4 is printed, mould pressing is carried out, and a microstructure which is obviously different from the first relief structure layer 2 is formed in the first area A; fourthly, the second relief structure layer 4 contains microparticles, and after drying and film forming, a structure with uneven surfaces is formed in the first region a. Fig. 5 shows a schematic diagram of a semi-finished structure obtained by embossing after the second relief structure layer 4 has been printed (i.e. the third method described above). The material of the second relief structure layer 4 may be selected from organic compounds such as acrylate, urethane acrylate, epoxy acrylate, and the like. In the second region B, the amount of printing per unit area of the second relief structure layer 4 should be significantly less than the specific volume of the second microstructure of the first relief structure layer 2, i.e. the second relief structure layer 4 still has the basic relief shape of the first relief structure layer 2 after printing.

S4, a material layer (second plating material layer) for obtaining the second plating layer 5 is formed, as shown in fig. 6.

In this embodiment, the second plating layer 5 is a multilayer interference light variable plating layer. Typically, the multilayer interference light variation plating layer 5 is composed of an absorption layer, a dielectric layer, and a reflection layer. The multilayer interference light variable coating layer presents different color characteristics when observed from the side of the absorption layer at different angles, so the multilayer interference light variable coating layer is generally formed by a reflecting layer, a dielectric layer and an absorption layer in sequence. The reflecting layer is generally made of thicker metal materials, has good reflectivity, and presents opaque or basically opaque characteristics in perspective observation; the dielectric layer is typically a compound material that is completely or substantially completely transparent; the absorption layer is generally a thin metal material, and the light transmission layer has a semitransparent characteristic. The reflecting layer can be formed by one or the combination of at least two of aluminum, silver, copper, tin, chromium, nickel and titanium, and the aluminum is preferably aluminum because the aluminum has low cost and is easy to be removed by acid liquor or alkali liquor; the dielectric layer can be formed by one or at least two of MgF2, SiO2, ZnS, TiN, TiO2, TiO, Ti2O3, Ti3O5, Ta2O5, Nb2O5, CeO2, Bi2O3, Cr2O3, Fe2O3, HfO2 or ZnO; the absorption layer can be made of one or at least two of nickel, chromium, aluminum, silver, copper, tin and titanium. The thickness of the reflective layer is generally selected from the range of 10nm to 80nm, preferably from 20nm to 50 nm. The thickness of the absorption layer is typically 3nm to 10 nm. The thickness of the dielectric layer 52 is determined by the desired optically variable color characteristics, typically 200nm to 600 nm.

S5, a material layer for obtaining the protective layer 6 (protective layer material layer) is formed as shown in fig. 7.

Generally, the protective layer material layer may be formed using a printing process. The amount of resist is such that the minimum thickness of the layer of resist material in the first region a is significantly greater than the minimum thickness in the second region B. The layer of protective material is typically at the very top of the microstructure at the minimum thickness of the microstructure. Thus, the protective effect of the protective layer material layer on the coating of the first area a is significantly higher than the protective effect on the coating of the second area B. The printing amount of the protective layer material layer on the unit area is generally more than 0.1g/m²Less than 0.6g/m². The smaller the viscosity of the protective layer material layer before printing, the more advantageous it is for leveling, and therefore the viscosity of the protective paste is generally less than 100cP, preferably less than 50 cP. Composition of the protective layer 6 or protective layer material layerThe ink may be a varnish or ink containing polyester, polyurethane, acrylic resin, or a combination thereof as a main resin.

S6, the multilayer body obtained in S5 is placed in a corrosive atmosphere capable of reacting with the first plating layer 3 until the first plating layer 3 and the second plating layer 5 located in the second region B are completely or partially removed, as shown in fig. 8.

As mentioned above, the protective layer 6 has a significantly higher protective effect on the coating of the first area a than on the coating of the second area B. Therefore, in a certain time, the corrosive atmosphere reaches and corrodes the underlying coating through the weak points of the protective layer of the second region B; during this time, the protective layer 6 effectively protects the plating layer of the first area a. Generally, it is only necessary that the first plating layer 3 be reactive with the etching atmosphere. After the first plating layer 3 on the second region B is etched, the second undulation structure layer 4, the second plating layer 5, and the protective layer 6 on the first plating layer 3 are also lifted off. In this way, the first plating layer 3 and the second plating layer 5 are obtained which are precisely located in the first region a. If the first coating 3 is aluminum or a coating containing aluminum, the etching atmosphere may be an acid solution or an alkali solution.

Thus, the semi-finished product of the optical anti-counterfeiting element is obtained, wherein the optical characteristics of the combination of the first relief structure layer 2 and the first plating layer 3 are shown in the first area A when observed from the first side, and the optical characteristics of the combination of the second relief structure layer 4 and the second plating layer 5 are shown in the first area A when observed from the second side.

The method for manufacturing the optical security element shown in fig. 2 generally further includes, after step S6, printing other functional coatings 7, such as anti-aging glue, to protect the optical coating and/or hot melt glue to adhere to other substrates.

Optical security elements of embodiments of the present invention may be fabricated as labels, wide strips, or security threads, and product applications include banknotes, securities, passports, tax banderoles, and the like.

Although the embodiments of the present invention have been described in detail with reference to the accompanying drawings, the embodiments of the present invention are not limited to the details of the above embodiments, and various simple modifications can be made to the technical solutions of the embodiments of the present invention within the technical idea of the embodiments of the present invention, and the simple modifications all belong to the protection scope of the embodiments of the present invention.

It should be noted that the various features described in the above embodiments may be combined in any suitable manner without departing from the scope of the invention. In order to avoid unnecessary repetition, the embodiments of the present invention do not describe every possible combination.

Those skilled in the art will understand that all or part of the steps in the method according to the above embodiments may be implemented by a program, which is stored in a storage medium and includes several instructions to enable a single chip, a chip, or a processor (processor) to execute all or part of the steps in the method according to the embodiments of the present application. And the aforementioned storage medium includes: a U-disk, a removable hard disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk or an optical disk, and other various media capable of storing program codes.

In addition, any combination of various different implementation manners of the embodiments of the present invention is also possible, and the embodiments of the present invention should be considered as disclosed in the embodiments of the present invention as long as the combination does not depart from the spirit of the embodiments of the present invention.