Optical security product

Abstract

The application provides an optical anti-counterfeiting product, comprising a carrier, the carrier having a first region and a second region, the first region and the second region being provided with an encoding pattern capable of being decoded into preset information, the encoding pattern comprising a first part and a second part, the light transmittance of the first part being different from that of the second part, the preset information being capable of being reproduced when a beam of light simultaneously irradiates the first part and the second part, the encoding pattern in the first region being capable of being decoded into first preset information, the encoding pattern in the second region being capable of being decoded into second preset information, the first preset information being different from the second preset information, the first region reproducing the first preset information for one eye of a person when a beam of light simultaneously irradiates the first region and the second region, and the second region reproducing the second preset information for the other eye of the person, so that a stereoscopic image is observed by the person. The application solves the problem in the prior art that the optical anti-counterfeiting product cannot be observed by naked eyes to have binocular parallax anti-counterfeiting characteristics.

Description

Technical Field

[0001] This invention relates to the field of optical anti-counterfeiting equipment technology, and more specifically, to an optical anti-counterfeiting product. Background Technology

[0002] To prevent counterfeiting, optical anti-counterfeiting technologies are widely used in banknotes, certificates, and other high-security and high-value-added printed materials, with very good results. For example, the new versions of the Euro and Canadian polymer banknotes use diffractive optically variable image wide bars, and the $100 US dollar note uses a technology called... The new 100 RMB banknote features a microlens security thread, and the new version uses an optically variable security thread. Visa, MasterCard, and my country's UnionPay credit cards use diffractive optically variable image hot stamping. Some countries also use diffractive optically variable image anti-counterfeiting technology on important documents such as ID cards, driver's licenses, and passports. To date, most banknotes, credit cards, passports, and other security cards worldwide employ optical anti-counterfeiting technology.

[0003] Optical anti-counterfeiting technology typically employs a specific optical microstructure to create unique optical effects, resulting in a distinctive and difficult-to-counterfeit visual appearance, thus achieving the goal of first-line anti-counterfeiting for the general public. However, simply possessing the visual effects required for mass anti-counterfeiting is insufficient to meet current market demands.

[0004] Hidden images reproduced by point light sources or lasers can provide unique anti-counterfeiting features, but these features all require projection onto a designated screen, limiting observation conditions and hindering identification. Forcing direct observation with the human eye would result in eye burns due to excessive energy, which is unacceptable to users. Furthermore, the optical anti-counterfeiting features provided by traditional hidden images are indistinguishable whether viewed with one or both eyes, failing to provide optical anti-counterfeiting features with binocular parallax.

[0005] In other words, existing optical anti-counterfeiting products have the problem that their anti-counterfeiting features, which exhibit binocular parallax, cannot be observed with the naked eye. Summary of the Invention

[0006] The main objective of this invention is to provide an optical anti-counterfeiting product to solve the problem that existing optical anti-counterfeiting products cannot be observed with the naked eye due to their binocular parallax features.

[0007] To achieve the above objectives, according to one aspect of the present invention, an optical anti-counterfeiting product is provided, comprising a carrier having a first region and a second region, wherein an optical anti-counterfeiting element is disposed in the first region and the second region, the optical anti-counterfeiting element having an encoded pattern capable of being decoded into preset information, the encoded pattern comprising a first part and a second part, the first part and the second part being interwoven, the light transmittance of the first part being different from that of the second part, and the preset information being reproduced when a beam of light simultaneously illuminates the first part and the second part, the encoded pattern in the first region being capable of being decoded into first preset information, and the encoded pattern in the second region being capable of being decoded into second preset information, the first preset information being different from that of the second preset information, and when a beam of light simultaneously illuminates the first region and the second region, the first region corresponding to one eye of a person reproduces the first preset information, and the second region corresponding to the other eye of a person reproduces the second preset information, so that a person can observe a three-dimensional image.

[0008] Furthermore, the first preset information and the second preset information are different side views of the stereoscopic image.

[0009] Furthermore, the first region and the second region are located on the same side or opposite sides of the carrier, and the distance between the first region and the second region on the plane of the carrier is the same as the distance between human eyes.

[0010] Furthermore, the carrier includes one of the following: banknotes, certificates, passports, and product packaging.

[0011] Furthermore, both the first region and the second region have multiple sub-regions. Each sub-region in the first region and each sub-region in the second region are mapped one-to-one to form multiple sub-region pairs. When a beam of light shines on the first region and the second region at the same time, each sub-region pair provides a first preset information with a specific color for one eye of the corresponding person and a second preset information with a specific color for the other eye of the corresponding person.

[0012] Furthermore, the encoding patterns between each sub-region pair are different, and each sub-region pair sequentially provides a series of first preset information with a specific preset color for one eye of the corresponding person and a series of second preset information with a specific color for the other eye of the corresponding person. The series of first preset information with a specific preset color and the series of second preset information with a specific color constitute a series of image frames.

[0013] Furthermore, the series of image frames includes one of switching between at least two patterns or switching between at least two angles of a stereoscopic figure.

[0014] Furthermore, a series of image frames includes one from animation or film.

[0015] Furthermore, when the encoding method of the encoding pattern in the first region is the same as that of the encoding pattern in the second region, the encoding pattern in the first region is different from that in the second region; or when the encoding method of the encoding pattern in the first region is different from that of the encoding pattern in the second region, the encoding pattern in the first region is the same as or different from that in the second region.

[0016] Furthermore, the optical anti-counterfeiting element also includes a substrate, the light transmittance of the first part is greater than that of the second part, the first part has a first structural layer and a first coating layer stacked together, the second part has a second structural layer and a second coating layer stacked together, the ratio of the surface area to the apparent area of ​​the first structural layer is greater than the ratio of the surface area to the apparent area of ​​the second structural layer, and the thickness of the first coating layer is less than the thickness of the second coating layer.

[0017] Furthermore, the first structural layer is connected to the substrate, the first plating layer is disposed on the surface of the first structural layer away from the substrate, the second structural layer is connected to the substrate, and the second plating layer is disposed on the surface of the second structural layer away from the substrate.

[0018] Furthermore, the first and second coatings are completed in the same process in one go.

[0019] Furthermore, both the first and second coatings are single-layer coatings.

[0020] Furthermore, the single-layer coating includes one of the following: a metal reflective layer, a semiconductor material layer, and a dielectric layer.

[0021] Furthermore, the first and second coatings are multilayer coatings.

[0022] Furthermore, the multilayer coating includes one of the following: multilayer metal coating, multilayer dielectric coating, or coating formed by alternating stacking of metal coating and dielectric coating.

[0023] Furthermore, the multilayer coating includes one of the following: a coating formed by sequentially stacking an absorption layer, a low refractive index dielectric layer, and a reflective layer, or a coating formed by sequentially stacking an absorption layer, a high refractive index dielectric layer, and a reflective layer.

[0024] Furthermore, the first structural layer has a first microstructure, and the second structural layer is a planar layer; or the first structural layer has a first microstructure, the second structural layer has a second microstructure, and the ratio of the surface area to the apparent area of ​​the first microstructure is greater than the ratio of the surface area to the apparent area of ​​the second microstructure.

[0025] Furthermore, the first microstructure is at least one of a non-diffractive structure and a diffractive structure; the second microstructure is at least one of a non-diffractive structure and a diffractive structure.

[0026] Furthermore, the period of the non-diffractive structure is greater than 5 micrometers; and / or the period of the diffractive structure is greater than 0.1 micrometers and less than 5 micrometers.

[0027] Furthermore, the optical anti-counterfeiting element also includes a filter layer that can transmit light of a preset color. The filter layer is disposed between the coding pattern and the substrate, or on the surface of the coding pattern away from the substrate, or in the coding pattern. When a beam of light illuminates the first part and the second part simultaneously, it can reproduce the preset information with the preset color.

[0028] Furthermore, the filter layer in the first region and the filter layer in the second region transmit light of the same or different preset colors.

[0029] Furthermore, the second part has grooves or cavities filled with a filling layer to make the light transmittance of the first part and the second part different.

[0030] Furthermore, the filler layer material includes at least one of ink, pigment, dye, and metal.

[0031] Furthermore, the first part has a filling layer, and the thickness of the filling layer in the first part is different from that in the second part.

[0032] Furthermore, the first part is a flat surface or the first part has a third microstructure.

[0033] Furthermore, the optical anti-counterfeiting element also includes a substrate and at least one translucent matte layer. The coded pattern is disposed on the substrate. The incident light is weakened after passing through the translucent matte layer. The translucent matte layer is disposed on the side of the substrate away from the coded pattern; and / or the translucent matte layer is disposed between the substrate and the coded pattern; and / or the translucent matte layer is disposed on the side of the coded pattern away from the substrate.

[0034] Furthermore, the translucent matte layer can provide light of a preset color.

[0035] Furthermore, the translucent matte layer is one of the following: a single-layer coating, a multi-layer coating, an ink layer, a pigment layer, a dye layer, a liquid crystal layer, or a co-extruded film layer.

[0036] Furthermore, the single-layer coating includes at least one of a metal coating, a semiconductor material coating, and a dielectric coating.

[0037] Furthermore, the multilayer coating includes one of the following: multilayer metal coating, multilayer dielectric coating, or coating formed by alternating stacking of metal coating and dielectric coating.

[0038] Furthermore, the multilayer coating includes: a coating formed by sequentially stacking an absorption layer, a low refractive index dielectric layer, and a reflective layer; or a coating formed by sequentially stacking an absorption layer, a high refractive index dielectric layer, and a reflective layer; or a coating formed by sequentially stacking a high refractive index dielectric layer, a low refractive index dielectric layer, and a high refractive index dielectric layer; wherein, the high refractive index dielectric layer refers to a dielectric layer with a refractive index greater than or equal to 1.7, and the low refractive index dielectric layer refers to a dielectric layer with a refractive index less than 1.7.

[0039] Furthermore, the materials in the first part and the materials in the second part are colored polymer materials.

[0040] Furthermore, colored polymer materials include one of the following: colored radiation-curable materials and colored thermoplastic materials.

[0041] Furthermore, the ratio of the area of ​​the first part to the area of ​​the second part is less than 1.

[0042] Furthermore, the ratio of the area of ​​the first part to the area of ​​the second part is less than 0.5.

[0043] Furthermore, the encoding pattern includes one of the following: Fourier transform pattern, Fresnel transform pattern, Moiré encoding pattern, barcode, QR code, Hilbert transform pattern, Abel transform pattern, Merlin transform pattern, or various custom transform patterns.

[0044] Furthermore, the optical anti-counterfeiting element also includes a substrate, on which the coding pattern is set. The substrate has a plate-like structure, which includes one of polyvinyl chloride (PVC) board, polyethylene terephthalate (PET) board, polycarbonate (PC) board, or glass board.

[0045] Furthermore, the optical anti-counterfeiting element also includes a functional layer, which is disposed between the substrate and the coded pattern; or the functional layer is disposed on the side of the coded pattern away from the substrate.

[0046] Furthermore, the functional layer includes at least one of the following: a release layer, a reinforcement layer, a protective layer, a magnetic layer, a fluorescent layer, and an infrared layer.

[0047] Furthermore, the light transmittance of both the first part and the second part is less than 80%; and / or the difference between the light transmittance of the first part and the light transmittance of the second part is greater than 10%.

[0048] Furthermore, the light transmittance of both the first and second parts is less than 40%; and / or the difference between the light transmittance of the first part and the light transmittance of the second part is greater than 20%.

[0049] Furthermore, a beam of light originates from a point source.

[0050] Furthermore, a beam of light originates from a monochromatic point source.

[0051] According to the technical solution of this invention, the optical anti-counterfeiting product includes a carrier, which has a first region and a second region. An optical anti-counterfeiting element is disposed in the first region and the second region. The optical anti-counterfeiting element has an encoding pattern that can be decoded into preset information. The encoding pattern includes a first part and a second part, which are intertwined. The light transmittance of the first part is different from that of the second part. When a beam of light shines on the first part and the second part at the same time, the preset information can be reproduced. The encoding pattern in the first region can be decoded into the first preset information, and the encoding pattern in the second region can be decoded into the second preset information. The first preset information and the second preset information are different. When a beam of light shines on the first region and the second region at the same time, the first region reproduces the first preset information corresponding to one eye of a person, and the second region reproduces the second preset information corresponding to the other eye of a person, so that a person can observe a three-dimensional image.

[0052] By setting a first region and a second region on the carrier, the first preset information reproduced in the first region and the second preset information reproduced in the second region combine to form a three-dimensional image that can be seen by the human eye. Simultaneously, dividing the coded pattern into a first part and a second part allows for the design of the optical properties of both parts. While ensuring the coded pattern can be decoded, the light transmittance of the coded pattern is reduced to prevent eye burns when viewing optical anti-counterfeiting products. Setting different light transmittances for the first and second parts allows for different absorption and reflection effects, resulting in varying light intensities transmitted through different areas, further reducing eye burns. By controlling the light transmittance of the first and second parts, the brightness of the coded pattern can be arbitrarily adjusted, ensuring that the transmitted light is received by the naked eye without causing burns, protecting the user's health. Furthermore, this allows the naked eye to directly observe the decoded preset information without the need for a screen, achieving a more easily identifiable second-line anti-counterfeiting feature. This allows for the naked eye to directly observe a three-dimensional second-line anti-counterfeiting feature, making it easy for the public to identify while possessing high anti-counterfeiting performance and being difficult to counterfeit. Attached Figure Description

[0053] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0054] Figure 1 A schematic diagram of the structure of an optical anti-counterfeiting product according to Embodiment 1 of the present invention is shown; and

[0055] Figure 2 It shows Figure 1 A schematic diagram of the structure of the anti-counterfeiting element of Zhongguang Optics;

[0056] Figure 3 It shows Figure 2 A magnified view of a portion of the coded pattern;

[0057] Figure 4 It shows Figure 3 A view of the coded pattern from one angle;

[0058] Figure 5 It shows Figure 1 A view of Zhongguang Optical anti-counterfeiting products from one angle;

[0059] Figure 6 It shows Figure 1 A pattern containing preset information for Zhongguang Optical anti-counterfeiting products;

[0060] Figure 7 It shows Figure 1 Another preset information pattern for Zhongguang Optical anti-counterfeiting products;

[0061] Figure 8 A schematic diagram of the structure of an optical anti-counterfeiting product according to Embodiment 2 of the present invention is shown;

[0062] Figure 9 It shows Figure 8 Hidden images corresponding to the first and second preset information of Zhongguang Optical anti-counterfeiting products;

[0063] Figure 10 It shows Figure 8 A top view of an optical anti-counterfeiting product;

[0064] Figure 11 A diagram showing the positional relationship between the first and second regions of another optical anti-counterfeiting product according to Embodiment 2 of the present invention is provided.

[0065] Figure 12 A diagram showing the positional relationship between the first and second regions of another optical anti-counterfeiting product according to Embodiment 2 of the present invention is provided.

[0066] Figure 13 This image shows an angle view of the optical anti-counterfeiting product according to Embodiment 5 of the present invention;

[0067] Figure 14 This image shows an angle view of an optical anti-counterfeiting product according to Embodiment Six of the present invention.

[0068] The above figures include the following reference numerals:

[0069] 10. Carrier; 11. First region; 111. First sub-region; 112. Second sub-region; 113. Third sub-region; 12. Second region; 121. Fourth sub-region; 122. Fifth sub-region; 123. Sixth sub-region; 20. Encoded pattern; 21. First part; 211. First structural layer; 212. First coating; 22. Second part; 221. Second structural layer; 222. Second coating; 30. A beam of light; 40. First preset information; 401. First hidden image; 402. Second hidden image; 403. Third hidden image; 50. Second preset information; 501. Fourth hidden image; 502. Fifth hidden image; 503. Sixth hidden image; 60. Substrate; 70. Optical anti-counterfeiting element; 80. Filling layer; 90. First graphic; 100. Second graphic. Detailed Implementation

[0070] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0071] It should be noted that, unless otherwise specified, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0072] In this invention, unless otherwise stated, directional terms such as "upper," "lower," "top," and "bottom" are generally used in relation to the direction shown in the accompanying drawings, or in relation to the vertical, perpendicular, or gravitational direction of the component itself; similarly, for ease of understanding and description, "inner" and "outer" refer to the inner and outer contours of each component itself, but the above directional terms are not intended to limit this invention.

[0073] To address the problem that existing optical anti-counterfeiting products cannot be observed with the naked eye due to their binocular parallax features, this invention provides an optical anti-counterfeiting product.

[0074] like Figures 1 to 14As shown, the optical anti-counterfeiting product includes a carrier 10, which has a first region 11 and a second region 12. An optical anti-counterfeiting element 70 is disposed in the first region 11 and the second region 12. The optical anti-counterfeiting element 70 has an encoding pattern 20 that can be decoded into preset information. The encoding pattern 20 includes a first part 21 and a second part 22, which are intertwined. The light transmittance of the first part 21 is different from that of the second part 22. When a beam of light 30 simultaneously illuminates the first part 21 and the second part 22, the preset information can be reproduced. The encoding pattern 20 in the first region 11 can be decoded into the first preset information 40, and the encoding pattern 20 in the second region 12 can be decoded into the second preset information 50. The first preset information 40 is different from the second preset information 50. When a beam of light 30 simultaneously illuminates the first region 11 and the second region 12, the first region 11 corresponds to one eye of a person and reproduces the first preset information 40, and the second region 12 corresponds to the other eye of a person and reproduces the second preset information 50, so that a person can observe a three-dimensional image.

[0075] By setting a first region 11 and a second region 12 on the carrier 10, the first preset information 40 reproduced in the first region 11 and the second preset information 50 reproduced in the second region 12 are combined to form a three-dimensional image that can be seen by the human eye. Simultaneously, the coded pattern 20 is divided into a first part 21 and a second part 22. The optical properties of the first part 21 and the second part 22 can be designed to reduce the light transmittance of the coded pattern 20 while ensuring that it can be decoded, thus preventing eye burns when viewing the optical anti-counterfeiting product. Setting different light transmittances for the first part 21 and the second part 22 allows for different absorption and reflection effects, resulting in different light intensities transmitted through different areas, reducing eye burns. By controlling the light transmittance of the first part 21 and the second part 22, the brightness of the coded pattern 20 can be arbitrarily adjusted, ensuring that the transmitted light from the coded pattern 20 can be received by the naked eye without causing burns, protecting the user's health. Furthermore, this allows the decoded preset information to be directly observed with the naked eye, eliminating the need for a screen to receive the decoded preset information, thus achieving a more easily identifiable second-line anti-counterfeiting feature. This allows a three-dimensional second-line anti-counterfeiting feature to be directly observed with the naked eye, making it easy for the public to identify while also providing high anti-counterfeiting performance and making it difficult to counterfeit.

[0076] It should be noted that, in addition to the first region 11 and the second region 12, the carrier 10 also has non-coded regions, while the coded pattern 20 covers the entire area of ​​the first region 11 and the second region 12. The first part 21 and the second part 22 are intertwined, which can be described as a complementary relationship between the first part 21 and the second part 22.

[0077] The first preset information 40 and the second preset information 50 can have multiple options, such as different sides of a three-dimensional graphic, different angles of a floating graphic, different angles of a sunken graphic, two related images, two unrelated images, etc. The colors of all images are not shown; in practical applications, the specific configuration of the optical anti-counterfeiting product used can be adjusted to arbitrarily select the desired options.

[0078] Specifically, the first preset information 40 and the second preset information 50 are different side views of the stereoscopic image. Setting the first preset information 40 and the second preset information 50 as different side views of the stereoscopic image ensures that the two eyes receive different information from the stereoscopic image, and that a stereoscopic image can be presented when both eyes observe it simultaneously.

[0079] Optionally, the first region 11 and the second region 12 are located on the same side or on opposite sides of the carrier 10, and the distance between the first region 11 and the second region 12 on the plane of the carrier 10 is the same as the distance between human eyes. The first region 11 and the second region 12 can be located on the same side of the carrier 10 at the same time, or they can be located on opposite sides of the carrier 10 respectively, as long as the distance between the first region 11 and the second region 12 on the plane of the carrier 10 is the same as the distance between human eyes, so as to ensure that the human eye can see the presented stereoscopic image.

[0080] The distance between the first region 11 and the second region 12 and the eyes on the plane where the carrier 10 is located is between 3 cm and 14 cm. Preferably, it is between 5 cm and 7 cm.

[0081] Specifically, the carrier 10 includes one of the following: banknotes, certificates, passports, and product packaging. In other words, the optical anti-counterfeiting element 70 can be set in banknotes, certificates, passports, and product packaging, enabling them to have anti-counterfeiting effects and prevent counterfeiting.

[0082] Optionally, when the encoding method of the coded pattern 20 in the first region 11 is the same as that of the coded pattern 20 in the second region 12, the coded pattern 20 in the first region 11 and the coded pattern 20 in the second region 12 are different. Using the same encoding method for the coded pattern 20 in the first region 11 and the coded pattern 20 in the second region 12 facilitates the production of the optical anti-counterfeiting element 70 and also facilitates the machine's decoding of the optical anti-counterfeiting element 70. Setting the coded pattern 20 in the first region 11 and the coded pattern 20 in the second region 12 to be different ensures the difference between the first preset information 40 and the second preset information 50, ensuring that the eyes see a three-dimensional image.

[0083] Alternatively, the encoding method of the coded pattern 20 in the first region 11 may differ from that of the coded pattern 20 in the second region 12. The coded pattern 20 in the first region 11 may be the same as or different from that in the second region 12. In this case, the coded pattern 20 in the first region 11 and the coded pattern 20 in the second region 12 can be the same or different, as long as the difference between the first preset information 40 and the second preset information 50 is maintained, ensuring that the image seen by both eyes is three-dimensional. Using different encoding methods for the coded pattern 20 in the first region 11 and the coded pattern 20 in the second region 12 increases the difficulty of production, places higher demands on the machine, and provides a higher level of anti-counterfeiting effect.

[0084] Specifically, the coding pattern 20 in the first region 11 and the second region 12 can be chosen arbitrarily.

[0085] like Figure 6 and Figure 7 As shown, the first graphic 90 corresponds to the first preset information 40, and the second graphic 100 corresponds to the second preset information 50.

[0086] To illustrate with a specific example, in Figure 6 In the specific example shown, the first preset information 40 and the second preset information 50 correspond to the left and right images of a stereoscopic portrait of a specific color, respectively. That is, the first graphic 90 is the left image of the stereoscopic portrait of a specific color, and the second graphic 100 is the right image of the stereoscopic portrait of a specific color. Thus, the left eye will observe the left image of the stereoscopic portrait of a specific color, and the right eye will observe the right image of the stereoscopic portrait of a specific color, thereby utilizing the principle of binocular parallax to form a stereoscopic portrait of a specific color. Of course, the first graphic 90 and the second graphic 100 can also be other shapes, such as different sides of a stereoscopic graphic, different angles of a floating graphic, different angles of a sunken graphic, two related images, or two unrelated images. The colors of all images are not shown; in practical applications, the colors can be arbitrarily selected by adjusting the specific configuration of the optical anti-counterfeiting elements used. Figure 7 The diagram shows some of the graphics that can be selected by the first graphic 90 and the second graphic 100; they will not be listed one by one here.

[0087] Example 1

[0088] like Figures 1 to 7As shown, the light transmittance of the first part 21 is greater than that of the second part 22. The first part 21 has a first structural layer 211 and a first coating layer 212 stacked together, and the second part 22 has a second structural layer 221 and a second coating layer 222 stacked together. The ratio of the surface area to the apparent area of ​​the first structural layer 211 is greater than that of the second structural layer 221. The thickness of the first coating layer 212 is less than the thickness of the second coating layer 222. By setting the first structural layer 211 and the first coating layer 212 on the first part 21, the light propagation paths are different when light passes through the first structural layer 211 and the second coating layer 222, thereby controlling the light transmittance and making the light transmittance of the first part 21 different from that of the second part 22. Similarly, by providing a second structural layer 221 and a second coating 222 on the second part 22, the light transmittance on the second part 22 can be controlled so that the light transmittance of the second part 22 is different from that of the first part 21. More precisely, the light transmittance of the first part 21 is controlled to be greater than that of the second part 22.

[0089] In this document, the term "apparent area" refers to the area of ​​a region projected onto a plane parallel to that region, i.e., the projected area ignoring the actual impact of undulating structures within that region; the term "surface area" refers to the actual area considering undulating structures within a region. Clearly, the ratio of a region's surface area to its apparent area is not less than 1. This can be understood as follows: on a flat region, the ratio of surface area to apparent area equals 1. On a region with undulating structures, the ratio of surface area to apparent area is greater than 1. In this application, since the ratio of the surface area to apparent area of ​​the first structural layer 211 is greater than that of the second structural layer 221, and the second structural layer 221 can be a flat structure, the ratio of the surface area to apparent area of ​​the first structural layer 211 is greater than 1. That is, the first structural layer 211 necessarily has undulating structures. Of course, the second structural layer 221 can also have such undulating structures, but the degree of undulation in the first structural layer 211 is greater than that in the second structural layer 221.

[0090] When the ratio of surface area to apparent area is different, in the same deposition process, the average thickness of the coating formed in the structure with a larger surface area per unit apparent area is less than the average thickness of the coating formed in the structure with a smaller surface area per unit apparent area.

[0091] By setting the ratio of the surface area to the apparent area of ​​the first structural layer 211 to be greater than that of the second structural layer 221, the undulation of the first structural layer 211 is increased, resulting in a stronger effect of light on the first structural layer 211. Simultaneously, the thickness of the first coating 212 formed on the first structural layer 211 is less than the thickness of the second coating 222 formed on the second structural layer 221, allowing more light to pass through the first coating 212, thus making the light transmittance of the first portion 21 greater than that of the second portion 22.

[0092] It should be noted that the optical anti-counterfeiting element 70 is an extremely thin and small structure. When light passes through the first structural layer 211 and the second structural layer 221, the difference in light transmittance between the two is not particularly obvious. However, when light passes through the first coating layer 212 and the second coating layer 222, which have different thicknesses, it results in an extremely obvious difference in light transmittance.

[0093] like Figure 4 As shown, the first structural layer 211 is connected to the substrate 60, and the first plating layer 212 is disposed on the surface of the first structural layer 211 away from the substrate 60. The second structural layer 221 is connected to the substrate 60, and the second plating layer 222 is disposed on the surface of the second structural layer 221 away from the substrate 60. Because the undulation of the first structural layer 211 is greater than that of the second structural layer 221, the surfaces of the first and second structural layers 211 away from the substrate 60 are uneven. Therefore, it is very easy to form the first plating layer 212 and the second plating layer 222 with different thicknesses on the surfaces of the first and second structural layers 211 and 221, simplifying the process operation.

[0094] It should be noted that the first plating layer 212 and the second plating layer 222 can be made of the exact same material, but with different thicknesses. Furthermore, the first plating layer 212 and the second plating layer 222 are completed in the same process, rather than being processed separately in their respective areas, which greatly simplifies the operation. Because the undulation of the first structural layer 211 is greater than that of the second structural layer 221, the first plating layer 212 and the second plating layer 222 with different thicknesses can be formed in the same process, or in other words, the thinner first plating layer 212 and the thicker second plating layer 222 can be formed in the same process.

[0095] Of course, the first plating layer 212 can be disposed between the first structural layer 211 and the substrate 60. However, since the thickness of the first plating layer 212 is at the micrometer level, its thickness cannot be precisely controlled, so it is generally not disposed between the first structural layer 211 and the substrate 60. The same applies to the second plating layer 222. Furthermore, in this embodiment, the first plating layer 212 and the second plating layer 222 need to be plated separately, which is extremely difficult to operate, and the first plating layer 212 and the second plating layer 222 are generally not processed separately. However, it is possible to do so if the process conditions permit.

[0096] The first coating 212 and the second coating 222 can be formed by physical deposition, chemical deposition, or a combination of both. Specifically, they can be formed using methods such as thermal evaporation, magnetron sputtering, MOCVD (metal-organic chemical vapor deposition), and molecular beam epitaxy.

[0097] Optionally, the first plating layer 212 and the second plating layer 222 can be single-layer plating. Using single-layer plating facilitates the processing of the first plating layer 212 and the second plating layer 222, resulting in high processing efficiency. Specifically, the single-layer plating can be one of a metal reflective layer, a semiconductor material layer, or a dielectric layer. That is, the single-layer plating can be a single-layer metal reflective layer, a single-layer semiconductor layer, or a single-layer dielectric layer.

[0098] It should be noted that the material of the metal reflective layer can be a pure metal or an alloy formed by a mixture of multiple metals. Specifically, it can be a pure metal or an alloy formed by a mixture of multiple metals, such as Al, Cu, Ni, Cr, Ag, Fe, Sn, Au, and Pt.

[0099] Of course, the first coating 212 and the second coating 222 can be multi-layered coatings. Multi-layered coatings are more advantageous for controlling light transmittance, but they are more difficult to manufacture. Specifically, a multi-layered coating can be one of the following: multiple metal coatings, multiple dielectric coatings, or a coating formed by alternating stacks of metal and dielectric coatings. Specifically, a coating formed by alternating stacks of metal and dielectric coatings can be a coating formed by sequentially stacking an absorption layer, a low-refractive-index dielectric layer, and a reflective layer, or a coating formed by sequentially stacking an absorption layer, a high-refractive-index dielectric layer, and a reflective layer.

[0100] The high-refractive-index dielectric layer refers to a dielectric layer with a refractive index greater than or equal to 1.7, and its materials can be ZnS, TiN, TiO2, TiO, Ti2O3, Ti3O5, Ta2O5, Nb2O5, CeO2, Bi2O3, Cr2O3, Fe2O3, HfO2, ZnO, etc. The low-refractive-index dielectric layer refers to a dielectric layer with a refractive index less than 1.7, and its materials can be MgF2, SiO2, etc. The reflective layer material can be a pure metallic material formed from Al, Cu, Ni, Cr, Ag, Fe, Sn, Au, Pt, etc., or an alloy formed from a mixture of multiple metals. The absorbent layer material can be a pure metallic material formed from Cr, Ni, Cu, Co, Ti, V, W, Sn, Si, Ge, etc., or an alloy formed from a mixture of multiple metals.

[0101] like Figure 4 As shown, the first structural layer 211 has a first microstructure, and the second structural layer 221 has a second microstructure. The ratio of the surface area to the apparent area of ​​the first microstructure is greater than the ratio of the surface area to the apparent area of ​​the second microstructure. Specifically, the first structural layer 211 and the second structural layer 221 are composed of surface undulation structures whose height varies with position on a two-dimensional plane. The first microstructure is located on the surface of the first structural layer 211 away from the substrate 60, and the second microstructure is located on the surface of the second structural layer 221 away from the substrate 60. This arrangement results in different degrees of undulation between the first structural layer 211 and the second structural layer 221, facilitating the subsequent formation of a first coating 212 and a second coating 222 of different thicknesses on the first microstructure and the second microstructure.

[0102] It should be noted that the arrangement of the first and second microstructures can change the optical path of some light, avoid excessive concentration of light intensity, reduce light intensity, and reduce damage to the human eye.

[0103] Optionally, the first microstructure and the second microstructure can be selected from at least one of non-diffractive structures and diffractive structures, respectively. The first microstructure and the second microstructure can both be non-diffractive structures, both can be diffractive structures, or one can be a diffractive structure and the other a non-diffractive structure.

[0104] Alternatively, the first microstructure can be partially non-diffractive and partially diffractive. Similarly, the second microstructure can be partially non-diffractive and partially diffractive. The specific choice can be made based on actual needs, as long as the ratio of the surface area to the apparent area of ​​the first microstructure is greater than the ratio of the surface area to the apparent area of ​​the second microstructure.

[0105] When the first and second microstructures have non-diffractive structures, the period of the non-diffractive structures is greater than 5 micrometers to ensure that no obvious rainbow colors are produced, so as to avoid affecting the observation of the preset information and ensure that the preset information can be accurately identified by the human eye.

[0106] When both the first and second microstructures possess diffraction structures, the period of the diffraction structure is greater than 0.1 micrometers and less than 5 micrometers. If the period of the diffraction structure is less than 0.1 micrometers, it is too small, which is detrimental to the fabrication of the diffraction structure. If the period of the diffraction structure is greater than 5 micrometers, it is too large, which can easily affect the preset information. Limiting the period of the diffraction structure to the range of 0.1 micrometers to 5 micrometers ensures the accuracy of the preset information while facilitating the fabrication of the diffraction structure.

[0107] Specifically, the optical anti-counterfeiting element 70 also includes a filter layer. This filter layer allows light of a preset color to pass through. The filter layer is disposed between the coded pattern 20 and the substrate 60, or on the surface of the coded pattern 20 away from the substrate 60, or within the coded pattern 20. When a beam of light 30 simultaneously illuminates the first portion 21 and the second portion 22, it can reproduce preset information with the preset color. This arrangement allows light of the preset color to pass through, so that the coded pattern 20 can display the preset information in the preset color after decoding. The preset color can also serve as an anti-counterfeiting feature, increasing anti-counterfeiting performance. The preset color, below the range through which the filter layer can pass through, can be designed according to actual needs.

[0108] Specifically, the filter layer in the first region 11 and the filter layer in the second region 12 transmit light of the same or different preset colors. When the filter layer in the first region 11 and the filter layer in the second region 12 transmit light of the same preset color, a three-dimensional image with the preset color can be displayed. When the filter layer in the first region 11 and the filter layer in the second region 12 transmit light of different preset colors, the displayed three-dimensional image has two colors.

[0109] It should be noted that when the preset color of light transmitted through the filter layer in the first region 11 and the filter layer in the second region 12 are different, the filter layer formed in the first region 11 and the filter layer in the second region 12 will be different. This requires high process conditions and is not easy to prepare, but it has a high anti-counterfeiting effect.

[0110] Specifically, the encoded pattern 20 includes one of the following: Fourier transform pattern, Fresnel transform pattern, Moiré code pattern, barcode, QR code, Hilbert transform pattern, Abelian transform pattern, Merlin transform pattern, or various custom transform patterns. It is necessary to ensure that the encoded pattern 20 can achieve optical transformation decoding; that is, when a beam of light, typically a laser, shines on the encoded pattern 20 at an appropriate distance, the hidden preset information can be reproduced. This defines the specific association and distribution of the interweaving of the first part 21 and the second part 22. Thus, the transmitted light field of the encoded pattern 20 further reproduces the preset information.

[0111] Of course, in addition to decoding optical changes in the encoded pattern 20, other decoding methods can also be used. For example, it can be decoded by computer or keypad.

[0112] Computer decoding involves reproducing the preset information, or the original pattern, on the computer screen. Keyboard decoding involves overlaying a keyboard on top of the original image, adjusting its position and alignment to reproduce the hidden original image. Keyboard decoding can store a virtual keyboard in the computer and read the coded pattern 20 into the computer for decoding using a program.

[0113] Through decoding, the encoded pattern 20 reveals the hidden original image. The decoding process is actually the inverse operation of the encoding process. Different encoding methods have different specific decoding methods.

[0114] The following examples illustrate several decoding methods for the encoded pattern 20.

[0115] Specifically, the encoded pattern 20 can be a Fourier transform pattern, that is, a Fourier pattern obtained after the original pattern has undergone a Fourier transform. The decoding method for the Fourier transform pattern can be computer decoding or optical transformation decoding.

[0116] The encoded pattern 20 can be a Fresnel transform pattern, that is, a Fresnel transform pattern obtained after the original pattern has undergone a Fresnel transform. The decoding method for the Fresnel transform pattern can be computer decoding or optical transformation decoding.

[0117] The coded pattern 20 can be a moiré-coded pattern, that is, a moiré-coded pattern obtained by designing the key plate and the original pattern and then moiré-coding it. The decoding method of the moiré-coded pattern can be computer decoding, optical change decoding, or key plate decoding.

[0118] The encoded pattern 20 can be a barcode, QR code, Hilbert transform pattern, Abel transform pattern, Merlin transform pattern, or various custom transform patterns. It only needs to ensure that these patterns can be decoded through optical transformation. Typically, they can also be decoded by a computer.

[0119] The optical anti-counterfeiting element also includes a substrate 60, on which the coding pattern 20 is disposed. The substrate 60 has a plate-like structure and may be one of polyvinyl chloride (PVC) board, polyethylene terephthalate (PET) board, polycarbonate (PC) board, or glass board. The selection of the substrate 60 should ensure that it can support the coding pattern 20 and that the substrate 60 and the coding pattern 20 are not easily separated.

[0120] Specifically, the light transmittance of both the first part 21 and the second part 22 is less than 80%. By controlling the ratio of transmitted light of the first part 21 and the second part 22 to less than 80%, the light intensity transmitted through the coded pattern 20 can be reduced, thereby reducing the risk of eye burns.

[0121] Preferably, the light transmittance of both the first part 21 and the second part 22 is less than 40%.

[0122] Specifically, the light transmittance of the first part 21 is more than 10% higher than that of the second part 22. This ensures the difference in light transmittance between the first part 21 and the second part 22, facilitating the control of the overall light transmittance of the coding pattern 20 and keeping the overall light transmittance of the coding pattern 20 within a reasonable range.

[0123] Preferably, the light transmittance of the first part 21 is 20% higher than that of the second part 22.

[0124] In practical applications, the difference in light transmittance can be achieved by adjusting the structural parameters of the first structural layer 211 and the second structural layer 221 to adjust the ratio of surface area to apparent area, as well as by adjusting the coating thickness and type of the first coating layer 212 and the second coating layer 222.

[0125] A beam of light 30 can come from other types of surface light sources, line light sources, parallel light sources, or point light sources, such as LED lights, incandescent lamps, mobile phone flashlights, etc. It can also be changed to a monochromatic light source, such as a gas laser, semiconductor laser, laser pointer, etc.

[0126] Preferably, one beam of light 30 originates from a point source.

[0127] More preferably, a beam of light 30 comes from a monochromatic point source.

[0128] It should be noted that when using a monochromatic point light source, the clarity of the reproduced hidden anti-counterfeiting image, i.e., the pre-information, as perceived by the human eye is optimal. However, when using a non-monochromatic point light source, due to the dispersion between different wavelengths of light, multiple images of different colors will appear corresponding to different wavelengths, resulting in multiple overlapping images. In practical applications, it has been found that this ghosting caused by different colored images is acceptable. Since obtaining a monochromatic light source is far more difficult than obtaining a non-monochromatic light source in practical applications, this discovery also makes the optical anti-counterfeiting product of this invention more easily identifiable and more conducive to practical application, which is something that traditional methods of reproducing hidden encoded images do not possess.

[0129] In addition, a non-point light source is equivalent to the superposition of multiple point light sources at different locations. Correspondingly, the human eye will receive images from multiple different locations, which will make the preset information unable to be accurately identified. This characteristic can be used to effectively hide anti-counterfeiting images under normal ambient light. At the same time, point light sources should be selected as much as possible when it is necessary to identify hidden anti-counterfeiting images.

[0130] In fact, only a single-color point light source is the best light source, and it hides the anti-counterfeiting image most clearly.

[0131] The following explanation will focus on two aspects: whether it is monochromatic or not, and whether the light source is a point light source or not.

[0132] (1) If the monochrome light is changed to a combination of multiple colors or even white light, then chromatic dispersion will occur and the image will be unclear because the diffraction angles of different colors of light are different. However, through testing, the degree of image blur caused by chromatic dispersion is acceptable.

[0133] (2) If the point light source is changed to a non-point light source such as a line light source or a surface light source, then the image will be equivalent to each point light source providing a hidden image at a different position, which is equivalent to multiple ghosting. The larger the light source size, the stronger the ghosting. The closer the light source is to the point light source, the weaker the ghosting becomes until it can be ignored. The superposition of multiple reproduced hidden images at different positions will affect the recognition of the hidden image. This is also why a hidden image is a hidden image, since ordinary natural light sources are not point light sources.

[0134] To illustrate with a specific example, in this case, the first microstructure is a one-dimensional holographic diffraction grating with a period of 1 micrometer and a depth of 500 nanometers, and the second microstructure is a one-dimensional holographic diffraction grating with a period of 2 micrometers and a depth of 120 nanometers. The ratio of surface area to apparent area is higher for the first microstructure than for the second microstructure. Therefore, during the same deposition process, the average thickness of the first coating 212, which is conformally covered on the first microstructure with greater undulation, is less than the average thickness of the second coating 222, which is conformally covered on the second microstructure with less undulation. When a beam of light 30 illuminates the coded pattern 20, the transmittance of the first portion 21 is higher than that of the second portion 22, thus reproducing the preset information.

[0135] The aforementioned optical anti-counterfeiting products allow the human eye to directly see the three-dimensional two-line anti-counterfeiting features without burning the eyes, making the optical anti-counterfeiting products easy to identify and difficult to counterfeit, thus increasing their anti-counterfeiting performance.

[0136] In addition, light sources that are usually easy to obtain are not monochromatic light, which causes dispersion defects in the hidden image. That is, the diffraction angle of light of different wavelengths is different, which can easily cause the hidden image to be blurry and make it impossible for the hidden image to provide easily identifiable color features.

[0137] This invention achieves an optical anti-counterfeiting product with two-line hidden anti-counterfeiting features through the overall design of optical microstructures. This optical anti-counterfeiting product can be directly observed by the human eye without causing harm. It can overcome dispersion defects, provide easily identifiable color features, and further provide optical anti-counterfeiting features that conform to binocular parallax.

[0138] Example 2

[0139] The difference from Embodiment 1 is that the first region 11 and the second region 12 are different.

[0140] like Figures 8 to 12 As shown, both the first region 11 and the second region 12 have multiple sub-regions. Each sub-region in the first region 11 and each sub-region in the second region 12 are mapped one-to-one to form multiple sub-region pairs. When a beam of light 30 simultaneously illuminates the first region 11 and the second region 12, each sub-region pair provides a first preset information 40 with a specific color for one eye of the corresponding person and a second preset information 50 with a specific color for the corresponding other eye of the corresponding person. The multiple sub-regions in the first region 11 and the multiple sub-regions in the second region 12 are in a one-to-one correspondence and are mutually mapped, and two mutually mapped sub-regions constitute a sub-region pair. A sub-region pair can present a stereoscopic image with a specific color.

[0141] It should be noted that multiple sub-region pairs can collectively form a complete stereoscopic image, with each sub-region pair being a part of that image. Alternatively, multiple sub-region pairs can correspond to multiple stereoscopic images, and the patterns in these images can be the same or different. Different stereoscopic images will be seen when viewed from different angles.

[0142] Of course, multiple sub-regions within the first region 11 and multiple sub-regions within the second region 12 can be consecutively connected, such as... Figure 10 As shown. The first region 11 and the second region 12 can also have different appearance designs.

[0143] Furthermore, the first region 11 and the second region 12 can be adjacent, such as... Figure 11 As shown. The first region 11 and the second region 12 can contain any number of sub-regions, as long as a series of preset information with specific colors can be provided accordingly.

[0144] In one specific embodiment, the encoding patterns 20 between each sub-region pair are different, and each sub-region pair sequentially provides a series of first preset information 40 with a specific preset color for one eye of the corresponding person and a series of second preset information 50 with a specific color for the corresponding other eye of the corresponding person. The series of first preset information 40 with a specific preset color and the series of second preset information 50 with a specific color constitute a series of image frames. In this embodiment, multiple sub-region pairs correspond to multiple stereoscopic images, and different stereoscopic images can be seen when observing different sub-region pairs. This can form a series of image changes, that is, a series of image frames, as the view is gradually changed from one angle to another.

[0145] Optionally, a series of image frames includes either switching between at least two patterns or switching between at least two angles of a 3D graphic. The switching between two patterns is a pattern change formed when viewed from one angle to another, to achieve a dynamic anti-counterfeiting effect. Of course, a series of images must include at least two pattern switching, but can also include switching between three, four, or more patterns to achieve a dynamic anti-counterfeiting effect.

[0146] Of course, it can also be a switch between two angles in a three-dimensional figure, where the shape of the three-dimensional figure can be seen from different angles when viewed from the first angle to the other.

[0147] Specifically, a series of image frames includes elements of animation and film. That is, an animation or film can be formed from a series of image frames; this effect is created by the changing images as the view is gradually shifted from one angle to another. Here, animation refers to a cartoon, and film refers to a movie.

[0148] It should be noted that the idea that a series of image frames can form an animation or movie refers to the relationship between these frames, not to the actual filming. It refers to the recognition and observation of hidden images, which means forming a continuous sequence of images.

[0149] To take a specific example, in Figure 8 In the specific embodiment shown, the first region 11 has three sub-regions: the first sub-region 111, the second sub-region 112, and the third sub-region 113. The second region 12 has three sub-regions: the fourth sub-region 121, the fifth sub-region 122, and the sixth sub-region 123. The first sub-region 111 and the fourth sub-region 121 are corresponding sub-region pairs, the second sub-region 112 and the fifth sub-region 122 are corresponding sub-region pairs, and the third sub-region 113 and the sixth sub-region 123 are corresponding sub-region pairs. The second sub-region 112 and the fifth sub-region 122 have the same shape, while the other shapes are different. When a beam of light 30 simultaneously illuminates the first region 11 and the second region 12, each sub-region provides a first preset information 40 with a specific preset color for one eye of the corresponding person and a second preset information 50 with a specific color for the other eye of the corresponding person. Figure 9 The diagram shows a first hidden image 401 corresponding to a first sub-region 111, a second hidden image 402 corresponding to a second sub-region 112, a third hidden image 403 corresponding to a third sub-region 113, a fourth hidden image 501 corresponding to a fourth sub-region 121, a fifth hidden image 502 corresponding to a fifth sub-region 122, and a sixth hidden image 503 corresponding to a sixth sub-region 123. The first hidden image 401, the second hidden image 402, and the third hidden image 403 together constitute the first preset information 40; the fourth hidden image 501, the fifth hidden image 502, and the fifth hidden image 502 together constitute the second preset information 50. The first preset information 40 and the second preset information 50 together form the preset information of the optical anti-counterfeiting product. Figure 9 The preset information of the optical anti-counterfeiting element shown is the tilt process of the stereoscopic image.

[0150] Example 3

[0151] The difference from Embodiment 1 is that the second structural layer 221 is different.

[0152] In this embodiment (not shown in the figure), the second structural layer 221 is a planar layer. The first structural layer 211 has a first microstructure. Compared to a flat surface, a surface undulation structure has a larger surface area per unit apparent area, and the surface area is positively correlated with the degree of undulation of the microstructure. The first microstructure is a one-dimensional non-diffraction grating with a period of 6 micrometers and a depth of 3 micrometers. The second structural layer 221 does not have a microstructure and is a flat surface. In the same deposition process, the average thickness of the first coating 212 that is conformally covered on the first microstructure with a large degree of undulation is less than the average thickness of the second coating 222 that is conformally covered on the flat surface of the second structural layer 221.

[0153] Example 4

[0154] The difference from Embodiment 1 is that this embodiment also has a functional layer (not shown in the figure).

[0155] Of course, it can also include only one functional layer, and this functional layer is disposed between the substrate 60 and the coding pattern 20. Or it can include only one functional layer, and this functional layer is disposed on the side of the coding pattern 20 away from the substrate 60.

[0156] It can also be multiple functional layers, all of which are disposed between the substrate 60 and the coding pattern 20. Alternatively, all functional layers can be disposed on the side of the coding pattern 20 away from the substrate 60. Or, several functional layers can be disposed between the substrate 60 and the coding pattern 20, and other functional layers can be disposed on the side of the coding pattern 20 away from the substrate 60.

[0157] The configuration of functional layers can be determined according to the specific usage requirements of the product. Functional layers include, but are not limited to, release layers, reinforcement layers, protective layers, magnetic layers, fluorescent layers, infrared layers, and adhesive layers.

[0158] One or more functional layers may be further applied to the upper surfaces of the first coating layer 212 and the second coating layer 222. For example, when using a peel-off hot stamping process to apply optical anti-counterfeiting products, the substrate 60 will be peeled off and will not exist on the target carrier 10. Therefore, the substrate 60 in the optical anti-counterfeiting products can be omitted or is not present.

[0159] Of course, functional layers can be provided on the side of the substrate 60 away from the coding pattern 20 according to actual needs. These will not be listed individually here.

[0160] To illustrate with a specific example, the substrate 60 is PET polyethylene terephthalate 601, and a first functional layer, which is a release layer, is disposed between the substrate 60 and the coded pattern 20. A second functional layer, which is an adhesive layer, is disposed on the side of the coded pattern 20 away from the substrate 60. This allows the optical anti-counterfeiting product in this example to have a peel-and-transfer function. That is, using, for example, a hot stamping process and the adhesive function of the adhesive layer, the coded pattern 20 can be hot stamped and pasted onto a high-security product carrier 10 such as banknotes, securities, credit cards, or passports, and the PET 601 can be peeled off, thus ensuring that the overall thickness of the structure hot stamped on the target carrier 10 is relatively thin. Preferably, at least a portion of the high-security product carrier 10 is transparent, and the transparent area at least partially overlaps with the coded pattern 20.

[0161] Example 5

[0162] The difference from Embodiment 1 is that the structures of the first part 21 and the second part 22 are different.

[0163] In this embodiment, the first part 21 and the second part 22 are not in the form of microstructures.

[0164] exist Figure 13 In the specific embodiment shown, the second part 22 has a groove or cavity, and the groove or cavity is filled with a filling layer 80 to make the light transmittance of the first part 21 and the second part 22 different. By setting the second part 22 to have a groove or cavity, and by placing the filling layer 80 in the groove or cavity, the optical properties of the first part 21 and the second part 22 are different, resulting in different light transmittances. This reduces the light transmittance of the encoded pattern 20 while ensuring that it can be decoded, thus preventing eye burns when viewing the optical anti-counterfeiting product. Setting the light transmittance of the first part 21 and the second part 22 to be different also allows for different absorption and reflection effects, resulting in different light intensities transmitted through different areas, thereby reducing eye burns.

[0165] By controlling the light transmittance of the first part 21 and the second part 22, the brightness of the coded pattern 20 can be adjusted arbitrarily, ensuring that the transmitted light from the coded pattern 20 can be received by the naked eye without causing burns and protecting the user's health. Furthermore, this allows the naked eye to directly observe the decoded preset information without needing a screen to receive it, achieving a more easily identifiable second-line anti-counterfeiting feature. This allows for the naked eye to directly observe a three-dimensional second-line anti-counterfeiting feature, making it easy for the public to identify while possessing high anti-counterfeiting performance and being difficult to counterfeit.

[0166] The filling layer 80 can be processed by a scraping method, in which filling material is applied to the entire surface of the coding pattern 20, and then scraped off with a scraper, so that the filling material in the depressions or cavities is retained, while the filling material in other areas is removed.

[0167] Specifically, the material of the filling layer 80 includes at least one of ink, pigment, dye, and metal. The filling layer 80 is formed by filling the recesses or cavities with ink, pigment, dye, metal, or combinations thereof, without the need for printing. This method is more advantageous, primarily because existing printing methods cannot achieve line widths below 10 micrometers. The coded pattern 20 in this invention has a line width below 10 micrometers; that is, the widths of the first part 21 and the second part 22 need to be below 10 micrometers to ensure the feasibility of reproducing the hidden image and the image quality. The recesses or cavities can be fabricated using micro-nano processing methods such as electron beam etching or laser direct writing, ensuring that the resolution of the first part 21 and the second part 22 is within the micro-nano size range, which is precisely what traditional printing processes cannot achieve. Therefore, the structure of this invention, containing recesses or cavities and filling them with ink, pigment, dye, metal, or combinations thereof, has unique advantages.

[0168] exist Figure 13 In the specific embodiment shown, the first part 21 is a flat surface. Setting the first part 21 as a flat surface facilitates the manufacturing of the first part 21; only grooves or cavities need to be formed on the second part 22.

[0169] Of course, it can also be a form where the first part 21 has a third microstructure, such as a holographic diffraction structure or non-diffraction structure with any surface shape, such as sinusoidal, rectangular, or serrated. This setting adds an extra parameter to limit the transmittance, ensuring the adjustability of the transmittance. However, this form is more difficult to manufacture, but it has a better anti-counterfeiting effect.

[0170] More specifically, the multilayer coating includes: a coating formed by sequentially stacking an absorption layer, a low refractive index dielectric layer, and a reflective layer; or a coating formed by sequentially stacking an absorption layer, a high refractive index dielectric layer, and a reflective layer; or a coating formed by sequentially stacking a high refractive index dielectric layer, a low refractive index dielectric layer, and a high refractive index dielectric layer; wherein, the high refractive index dielectric layer refers to a dielectric layer with a refractive index greater than or equal to 1.7, and the low refractive index dielectric layer refers to a dielectric layer with a refractive index less than 1.7.

[0171] Specifically, the ratio of the area of ​​the first part 21 to the area of ​​the second part 22 is less than 1. This ratio ensures that the areas of the first part 21 and the second part 22 are unequal, allowing for control of light transmittance. Preferably, the ratio of the area of ​​the first part 21 to the area of ​​the second part 22 is less than 0.5.

[0172] Specifically, the depth of the depression or cavity is greater than 0.5 micrometers and less than or equal to 20 micrometers. Preferably, the depth of the depression or cavity is greater than 0.5 micrometers and less than or equal to 5 micrometers.

[0173] To illustrate with a specific example, in Figure 6 In the specific embodiment shown, the first part 21 is a flat surface, and the second part 22 is recessed or hollow, with a depth of 2 micrometers. The recess or hollow contains a filling layer 80 formed of red metallic ink. When a beam of light 30 shines on the optical anti-counterfeiting product, the light from the first part 21 passes almost directly through, while the light from the second part 22 is filtered by the red metallic ink and appears red. Based on the coding pattern 20, the transmitted light forms the preset red information. By adjusting the duty cycle of the first part 21 and the second part 22, for example, by reducing the area ratio of the first part 21 and increasing the area ratio of the second part 22, the flux of the transmitted light from the first part 21 can be controlled. Simultaneously, by controlling the thickness of the red metallic ink in the second part 22, the intensity of the transmitted light from the second part 22 can be controlled. Thus, the intensity of the transmitted light can be controlled, thereby achieving a clear red preset information that can be directly observed with the naked eye.

[0174] Of course, red metallic ink can be replaced with ink, pigment, dye, metal or a combination thereof.

[0175] Example 6

[0176] The difference from Embodiment 5 is that in this embodiment, the first part 21 also has a filling layer 80.

[0177] exist Figure 14 In the specific embodiment shown, the first portion 21 has a filling layer 80, and the thickness of the filling layer 80 at the first portion 21 is different from that at the second portion 22. Of course, a filling layer 80 can also be provided in the first portion 21, but the thickness of the filling layer 80 in the first portion 21 and the filling layer 80 in the second portion 22 is different, so that the transmittance of the first portion 21 and the second portion 22 is different.

[0178] Specifically, the thickness of the filling layer 80 at the first part 21 is less than the thickness of the filling layer 80 at the second part 22, thereby making the light intensity transmitted through the first part 21 greater than the light intensity transmitted through the second part 22.

[0179] The filling layer 80 at the first part 21 and the filling layer 80 at the second part 22 can be processed simultaneously. For example, by using a scraping method, the filling material is applied to the entire surface of the coding pattern 20. Then, a cylindrical roller is used to roll and clean the surface of the coding pattern 20 to form a filling layer 80. Due to the presence of depressions and cavities, the thickness of the filling layer 80 at the second part 22 is greater than the thickness of the filling layer 80 at the first part 21.

[0180] By adjusting the duty cycle of the first part 21 and the second part 22, for example, by reducing the area ratio of the first part 21 and increasing the area ratio of the second part 22, the flux of light transmitted through the first part 21 can be controlled. Simultaneously, by controlling the depth of the depression or cavity, the thickness of the filling layer 80 at the first part 21, and the thickness of the filling layer 80 at the second part 22, the intensity and color of the light transmitted through the first part 21 and the second part 22 can be controlled, so that preset information of a clear preset color can be directly observed by the naked eye.

[0181] Optionally, the default color can be red.

[0182] Example 7

[0183] The difference from Example 4 is that the materials of the first part 21 and the second part 22 are different.

[0184] In this embodiment, the materials of the first part 21 and the second part 22 are colored polymer materials. This arrangement allows the optical anti-counterfeiting product to transmit light of a preset color to form preset information of the preset color.

[0185] More specifically, the colored polymer material includes one of a colored radiation-curable material and a colored thermoplastic material. The colored radiation-curable material and the colored thermoplastic material can be coated to form the first part 21 and the second part 22, which facilitates the production of the first part 21 and the second part 22.

[0186] It should be noted that colored polymer materials can be inherently colored, or they can achieve their color characteristics by doping with inks, pigments, dyes, metals, or combinations thereof.

[0187] In this embodiment, the flux of light transmitted through the first part 21 can be controlled by adjusting the duty cycle of the first part 21 and the second part 22, for example, by reducing the area ratio of the first part 21 and increasing the area ratio of the second part 22. Simultaneously, the intensity and color of the transmitted light from the first part 21 and the second part 22 can be further controlled by controlling the depth of the depression or cavity, the thickness of the filling layer 80, and the thicknesses of the first part 21 and the second part 22. The color of the light transmitted through the first part 21 is determined by the material of the first part 21, while the color of the light transmitted through the second part 22 is determined by both the material of the second part 22 and the filling layer 80, thus enabling the naked eye to directly observe clear preset color information.

[0188] Example 8

[0189] The difference from Embodiment 4 is that the optical anti-counterfeiting element 70 in this embodiment also includes a semi-transparent matte layer.

[0190] In this embodiment, the optical anti-counterfeiting element 70 further includes a substrate 60 and at least one translucent matte layer. The coded pattern 20 is disposed on the substrate 60. The incident light is weakened after passing through the translucent matte layer. The translucent matte layer is disposed on the side of the substrate 60 away from the coded pattern 20. The main function of the translucent matte layer is to reduce the light intensity so that the preset information can be directly seen by the naked eye, making it easy for the public to identify.

[0191] It should be noted that both the first region 11 and the second region 12 have a semi-transparent matte layer.

[0192] Of course, the semi-transparent matte layer can be positioned between the substrate 60 and the coded pattern 20. Alternatively, the semi-transparent matte layer can be positioned on the side of the coded pattern 20 furthest from the substrate 60. The specific location of the semi-transparent matte layer can be determined based on actual needs and the complexity of the manufacturing process.

[0193] Specifically, a semi-transparent matte layer can provide light of a preset color. The semi-transparent matte layer can be configured to allow light of a certain wavelength or a certain wavelength range to pass through, so that light of a preset color can pass through, thus providing light of the preset color.

[0194] Optionally, the translucent matte layer can be one of the following: a single-layer coating, a multi-layer coating, an ink layer, a pigment layer, a dye layer, a liquid crystal layer, or a co-extruded film layer. The translucent matte layer can be either a single-layer or a multi-layer coating, as long as it effectively reduces light intensity. The single-layer and multi-layer coatings are the same as those described above.

[0195] When the semi-transparent matte layer is a single-layer coating, the single-layer coating includes at least one of a metal coating, a semiconductor material coating, and a dielectric coating. When the semi-transparent matte layer is a multi-layer coating, the multi-layer coating includes one of a multi-layer metal coating, a multi-layer dielectric coating, or a coating formed by alternating stacks of metal coatings and dielectric coatings.

[0196] It should be noted that the metal coating can be a pure metal coating or an alloy coating.

[0197] The liquid crystal layer can be formed from cholesteric liquid crystal materials, thereby controlling the color of transmitted light. The co-extruded film, on the other hand, is a stacked structure with high and low refractive indices, capable of controlling the color of transmitted light. It should be noted that the co-extruded film is a stacked structure achieved through polymer materials, not a coating.

[0198] In this embodiment, the flux of transmitted light from the first part 21 can be controlled by adjusting the duty cycle of the first part 21 and the second part 22, for example, by reducing the area ratio of the first part 21 and increasing the area ratio of the second part 22. Simultaneously, the intensity and color of the transmitted light from the first part 21 and the second part 22 can be further controlled by controlling the depth of the depression or cavity, the thickness of the filling layer 80, and the thickness of the translucent matting layer in the first part 21 and the second part 22. The color of the transmitted light from the first part 21 is determined by the translucent matting layer, while the color of the transmitted light from the second part 22 is jointly determined by the translucent matting layer and the filling layer 80, so that the preset information of a clear preset color can be directly observed by the naked eye.

[0199] Example 9

[0200] The difference from Embodiment 1 is that the first coating 212 and the second coating 222 of the optical anti-counterfeiting element 70 can transmit light of a preset color.

[0201] In other words, in this embodiment, instead of setting a filter layer, the first coating layer 212 and the second coating layer 222 are configured to have color filtering function, which can selectively absorb or reflect the incident spectrum to control the color of the transmitted light. The preset information is reproduced by decoding the encoded pattern 20, so the provided two-line anti-counterfeiting feature has a specific color, rather than a color determined simply by the color of the incident light.

[0202] Since the preset information has a specific color, rather than a color determined solely by the color of the incident light, it avoids the defects of unclear images or lack of color features caused by chromatic dispersion when the incident light is not monochromatic.

[0203] Obviously, the embodiments described above are merely some, not all, embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort should fall within the scope of protection of the present invention.

[0204] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0205] It should be noted that the terms "first," "second," etc., used in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in sequences other than those illustrated or described herein.

[0206] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. An optical anti-counterfeiting product, characterized in that, The device includes a carrier (10) having a first region (11) and a second region (12). Optical anti-counterfeiting elements (70) are disposed in the first region (11) and the second region (12). The optical anti-counterfeiting elements (70) have an encoding pattern (20) that can be decoded into preset information. The encoding pattern (20) includes a first part (21) and a second part (22), which are interwoven. The light transmittance of the first part (21) is different from that of the second part (22). When a beam of light (30) simultaneously illuminates the first part (21) and the second part (22), the preset information can be reproduced. The encoded pattern (20) in the first region (11) can be decoded into first preset information (40), and the encoded pattern (20) in the second region (12) can be decoded into second preset information (50). The first preset information (40) and the second preset information (50) are different. When a beam of light (30) simultaneously illuminates the first region (11) and the second region (12), the first region (11) corresponds to one of the person's eyes and reproduces the first preset information (40), and the second region (12) corresponds to the other of the person and reproduces the second preset information (50), so that the person can observe a stereoscopic image.

2. The optical anti-counterfeiting product according to claim 1, characterized in that, The first preset information (40) and the second preset information (50) are different side views of the stereoscopic image.

3. The optical anti-counterfeiting product according to claim 1, characterized in that, The first region (11) and the second region (12) are located on the same side or both sides of the carrier (10), and the distance between the first region (11) and the second region (12) on the plane where the carrier (10) is located is the same as the distance between a person's eyes.

4. The optical anti-counterfeiting product according to claim 3, characterized in that, The carrier (10) includes one of banknotes, certificates, passports, and product packaging.

5. The optical anti-counterfeiting product according to claim 1, characterized in that, Both the first region (11) and the second region (12) have multiple sub-regions. Each sub-region in the first region (11) and each sub-region in the second region (12) are mapped one-to-one to form multiple sub-region pairs. When a beam of light (30) simultaneously illuminates the first region (11) and the second region (12), each sub-region pair provides the first preset information (40) with a specific color for one eye of the corresponding person and the second preset information (50) with a specific color for the other eye of the corresponding person.

6. The optical anti-counterfeiting product according to claim 5, characterized in that, The encoding patterns (20) between each of the sub-region pairs are different, and each of the sub-region pairs sequentially provides a series of first preset information (40) with a specific preset color for one eye of the corresponding person and a series of second preset information (50) with a specific color for the other eye of the corresponding person. The series of first preset information (40) with a specific preset color and the series of second preset information (50) with a specific color constitute a series of image frames.

7. The optical anti-counterfeiting product according to claim 6, characterized in that, The series of image frames includes one of the following: switching between at least two patterns or switching between at least two angles of a stereoscopic graphic.

8. The optical anti-counterfeiting product according to claim 6, characterized in that, The series of image frames includes animation.

9. The optical anti-counterfeiting product according to claim 6, characterized in that, The series of image frames includes movies.

10. The optical anti-counterfeiting product according to claim 1, characterized in that, When the encoding method of the encoding pattern (20) in the first region (11) is the same as that of the encoding pattern (20) in the second region (12), the encoding pattern (20) in the first region (11) is different from the encoding pattern (20) in the second region (12); or When the encoding method of the encoding pattern (20) in the first region (11) is different from the encoding method of the encoding pattern (20) in the second region (12), the encoding pattern (20) in the first region (11) is the same as or different from the encoding pattern (20) in the second region (12).

11. The optical anti-counterfeiting product according to claim 1, characterized in that, The optical anti-counterfeiting element (70) further includes a substrate (60), the light transmittance of the first part (21) is greater than that of the second part (22), the first part (21) has a first structural layer (211) and a first coating (212) stacked together, the second part (22) has a second structural layer (221) and a second coating (222) stacked together, the ratio of the surface area to the apparent area of ​​the first structural layer (211) is greater than that of the second structural layer (221), and the thickness of the first coating (212) is less than that of the second coating (222).

12. The optical anti-counterfeiting product according to claim 11, characterized in that, The first structural layer (211) is connected to the substrate (60), the first plating layer (212) is disposed on the side surface of the first structural layer (211) away from the substrate (60), the second structural layer (221) is connected to the substrate (60), and the second plating layer (222) is disposed on the side surface of the second structural layer (221) away from the substrate (60).

13. The optical anti-counterfeiting product according to claim 12, characterized in that, The first coating (212) and the second coating (222) are completed in the same process at one time.

14. The optical anti-counterfeiting product according to claim 11, characterized in that, The first coating (212) and the second coating (222) are single-layer coatings.

15. The optical anti-counterfeiting product according to claim 14, characterized in that, The single-layer coating includes one of a metal reflective layer, a semiconductor material layer, and a dielectric layer.

16. The optical anti-counterfeiting product according to claim 11, characterized in that, The first coating (212) and the second coating (222) are multilayer coatings.

17. The optical anti-counterfeiting product according to claim 16, characterized in that, The multilayer coating includes one of the following: multilayer metal coating, multilayer dielectric coating, or coating formed by alternating stacks of metal coating and dielectric coating.

18. The optical anti-counterfeiting product according to claim 16, characterized in that, The multilayer coating includes one of the following: a coating formed by sequentially stacking an absorption layer, a low refractive index dielectric layer, and a reflective layer, or a coating formed by sequentially stacking an absorption layer, a high refractive index dielectric layer, and a reflective layer.

19. The optical anti-counterfeiting product according to claim 11, characterized in that, The first structural layer (211) has a first microstructure, and the second structural layer (221) is a planar layer; or The first structural layer (211) has a first microstructure, the second structural layer (221) has a second microstructure, and the ratio of the surface area to the apparent area of ​​the first microstructure is greater than the ratio of the surface area to the apparent area of ​​the second microstructure.

20. The optical anti-counterfeiting product according to claim 19, characterized in that, The first microstructure is at least one of a non-diffractive structure and a diffractive structure; The second microstructure is at least one of a non-diffractive structure and a diffractive structure.

21. The optical anti-counterfeiting product according to claim 20, characterized in that, The period of the non-diffraction structure is greater than 5 micrometers; and / or The period of the diffraction structure is greater than 0.1 micrometers and less than 5 micrometers.

22. The optical anti-counterfeiting product according to claim 20, characterized in that, The optical anti-counterfeiting element (70) also includes a filter layer, which is capable of transmitting light of a preset color. The filter layer is disposed between the coded pattern (20) and the substrate (60); or The filter layer is disposed on the surface of the coded pattern (20) away from the substrate (60); or The filter layer is disposed in the coding pattern (20); When a beam of light (30) simultaneously illuminates the first part (21) and the second part (22), the preset information with a preset color can be reproduced.

23. The optical anti-counterfeiting product according to claim 22, characterized in that, The filter layer in the first region (11) and the filter layer in the second region (12) transmit light of the same or different preset color.

24. The optical anti-counterfeiting product according to claim 1, characterized in that, The second part (22) has a groove or cavity, the groove or cavity being filled with a filler layer (80) to make the light transmittance of the first part (21) and the second part (22) different.

25. The optical anti-counterfeiting product according to claim 24, characterized in that, The material of the filler layer (80) includes at least one of ink, pigment, dye, and metal.

26. The optical anti-counterfeiting product according to claim 24, characterized in that, The first part (21) has the filling layer (80), and the filling layer (80) at the first part (21) has a different thickness than the filling layer (80) at the second part (22).

27. The optical anti-counterfeiting product according to claim 24, characterized in that, The first part (21) is a flat surface or the first part (21) has a third microstructure.

28. The optical anti-counterfeiting product according to claim 24, characterized in that, The optical anti-counterfeiting element further includes a substrate (60) and at least one translucent matte layer. The coding pattern (20) is disposed on the substrate (60). The incident light intensity weakens after passing through the translucent matte layer. The translucent matte layer is disposed on the side of the substrate (60) away from the coded pattern (20); and / or The translucent matte layer is disposed between the substrate (60) and the coded pattern (20); and / or The translucent matte layer is disposed on the side of the coded pattern (20) away from the substrate (60).

29. The optical anti-counterfeiting product according to claim 28, characterized in that, The translucent matte layer can provide light of a preset color.

30. The optical anti-counterfeiting product according to claim 28, characterized in that, The semi-transparent matte layer is one of the following: a single-layer coating, a multi-layer coating, an ink layer, a pigment layer, a dye layer, a liquid crystal layer, or a co-extruded film layer.

31. The optical anti-counterfeiting product according to claim 30, characterized in that, The single-layer coating includes at least one of a metal coating, a semiconductor material coating, and a dielectric coating.

32. The optical anti-counterfeiting product according to claim 30, characterized in that, The multilayer coating includes one of the following: multilayer metal coating, multilayer dielectric coating, or coating formed by alternating stacks of metal coating and dielectric coating.

33. The optical anti-counterfeiting product according to claim 30, characterized in that, The multilayer coating includes: A coating formed by sequentially stacking an absorption layer, a low-refractive-index dielectric layer, and a reflective layer; or A coating formed by sequentially stacking an absorption layer, a high-refractive-index dielectric layer, and a reflective layer; or A coating formed by sequentially stacking a high-refractive-index dielectric layer, a low-refractive-index dielectric layer, and a high-refractive-index dielectric layer; The high refractive index medium layer refers to a medium layer with a refractive index greater than or equal to 1.7, and the low refractive index medium layer refers to a medium layer with a refractive index less than 1.

7.

34. The optical anti-counterfeiting product according to claim 30, characterized in that, The materials of the first part (21) and the second part (22) are colored polymer materials.

35. The optical anti-counterfeiting product according to claim 34, characterized in that, The colored polymer material includes one of the following: a colored radiation-curable material and a colored thermoplastic material.

36. The optical anti-counterfeiting product according to claim 24, characterized in that, The ratio of the area of ​​the first part (21) to the area of ​​the second part (22) is less than 1.

37. The optical anti-counterfeiting product according to claim 24, characterized in that, The ratio of the area of ​​the first part (21) to the area of ​​the second part (22) is less than 0.

5.

38. The optical anti-counterfeiting product according to any one of claims 1 to 37, characterized in that, The encoding pattern (20) includes one of the following: Fourier transform pattern, Fresnel transform pattern, Moiré encoding pattern, barcode, QR code, Hilbert transform pattern, Abel transform pattern, Merlin transform pattern, or various custom transform patterns.

39. The optical anti-counterfeiting product according to any one of claims 1 to 37, characterized in that, The optical anti-counterfeiting element also includes a substrate (60), and the coding pattern (20) is disposed on the substrate (60). The substrate (60) is a plate structure, and the plate structure includes one of polyvinyl chloride (PVC) plate, polyethylene terephthalate (PET) plate, polycarbonate (PC) plate or glass plate.

40. The optical anti-counterfeiting product according to claim 39, characterized in that, The optical anti-counterfeiting element also includes a functional layer. The functional layer is disposed between the substrate (60) and the coding pattern (20); or The functional layer is disposed on the side of the coded pattern (20) away from the substrate (60).

41. The optical anti-counterfeiting product according to claim 40, characterized in that, The functional layer includes at least one of the following: a release layer, a reinforcement layer, a protective layer, a magnetic layer, a fluorescent layer, and an infrared layer.

42. The optical anti-counterfeiting product according to any one of claims 1 to 37, characterized in that, The transmittance of both the first part (21) and the second part (22) is less than 80%; and / or The difference between the transmittance of the first part (21) and the transmittance of the second part (22) is greater than 10%.

43. The optical anti-counterfeiting product according to any one of claims 1 to 37, characterized in that, The transmittance of both the first part (21) and the second part (22) is less than 40%; and / or The difference between the transmittance of the first part (21) and the transmittance of the second part (22) is greater than 20%.

44. The optical anti-counterfeiting product according to any one of claims 1 to 37, characterized in that, The beam of light (30) originates from a point source.

45. The optical anti-counterfeiting product according to any one of claims 1 to 37, characterized in that, The beam of light (30) comes from a monochromatic point light source.

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