Cat eye film with effect of enhancing depth of field and packaging box body of cat eye film

Abstract

The utility model discloses a cat eye film with an effect of enhancing depth of field and a packaging box body of the cat eye film, which belong to the technical field of 3D (three-dimensional) cold laminating films and comprise a focusing lens layer, a gradient refraction layer, a light absorption isolation layer, a nano scattering layer and a high-reflection medium layer which are sequentially compounded from the surface to the bottom. Through the collaborative construction of the gradient refraction layer and the nano scattering layer, the optical limitation of the existing single-layer cat eye film is broken through, and the gradient refraction layer prolongs the light refraction path and simulates deep parallax; the nano scattering layer increases the angle diversity of emergent light, and combines the light absorption isolation layer to inhibit stray light and the high reflection layer to improve brightness, so that the depth-of-field effect is effectively improved.

Description

Technical Field

[0001] This utility model belongs to the field of 3D cold lamination technology, specifically relating to a cat-eye film with enhanced depth of field effect and its packaging box. Background Technology

[0002] Cat-eye film (also known as 3D cold lamination film) is a novel material based on optical lens array imaging. Its core structure consists of "cat-eye stripes" embossed on the surface, creating a stereoscopic visual effect by refracting light through microlenses. This film is typically less than 1 millimeter thick, but it can utilize optical illusions to present a significant sense of depth, thus visually simulating three-dimensional space. Thanks to its lightweight and highly decorative properties, cat-eye film is widely used in electronic product casings, tobacco and alcohol packaging boxes, and other applications to enhance product appeal and added value.

[0003] However, the depth-of-field effect of existing cat-eye films has limitations. For example, Chinese patent document CN203846349U provides a 3D cat-eye composite paper, whose structure consists of a varnish layer, a three-dimensional cold-laminated film layer, an adhesive layer, a paper layer, and a back-coated adhesive layer sequentially laminated together. While this design can achieve a basic stereoscopic visual effect, it is limited by the structure of a single-layer three-dimensional cold-laminated film layer, resulting in a relatively limited visual depth of field, typically only 2-3 cm, failing to produce an enhanced optical illusion of depth. In practical applications, enhanced depth-of-field effects create a sense of depth separation between the modulated visual subject and the background, significantly improving visual impact; simultaneously, the greater the depth of field, the more complex the optical imaging path, increasing the difficulty of counterfeiting and enhancing anti-counterfeiting performance. Therefore, effectively enhancing the depth-of-field effect of cat-eye films has become a key challenge in improving their functionality and market competitiveness.

[0004] Therefore, it is necessary to propose a cat-eye film and its packaging box that enhances the depth of field effect in order to overcome the shortcomings of the existing technology. Summary of the Invention

[0005] In response to the problems in related technologies, this utility model proposes a cat eye film with enhanced depth of field effect and its packaging box to solve the technical problem that the visual depth of field of existing cat eye films is relatively limited.

[0006] The technical solution of this utility model is achieved as follows: a cat-eye film with enhanced depth-of-field effect, comprising, sequentially laminated from the surface to the bottom:

[0007] Focusing lens layer: with a thickness of 15-30μm, and a convex lens array with a diameter of 50-100μm on the surface, and a lens center-to-center distance of 60-120μm;

[0008] Gradient refractive layer: with a thickness of 20-40μm, its lens curvature radius decreases by 15%-25% along the thickness direction, and its coaxial alignment offset with the focusing lens layer is ≤5μm;

[0009] Light-absorbing isolation layer: 0.5-2μm thick, with an array of light-transmitting openings, the opening diameter being 20-40μm;

[0010] Nano-scattering layer: 5-15μm thick, with an array of pits distributed on the surface, the pits having a diameter of 600-900nm and a depth of 200-500nm;

[0011] High reflectivity medium layer: 0.8-1.2 μm thick, covering the bottom surface of the nano-scattering layer.

[0012] This invention overcomes the optical limitations of existing single-layer cat's eye films through the synergistic construction of a gradient refractive layer and a nano-scattering layer. The gradient layer extends the light refraction path to simulate deep parallax; the nano-scattering layer increases the diversity of the emitted light angle, and combined with the light-absorbing isolation layer to suppress stray light and the high-reflection layer to improve brightness, the depth-of-field effect is effectively improved.

[0013] As a further improvement to the above solution, the light-transmitting openings of the light-absorbing isolation layer are arranged in a hexagonal grid pattern, with a grid line width ≤3μm and an alignment error between the opening area and the center of the focusing lens ≤2μm. The hexagonal grid pattern is precisely aligned with the center of the lens to form an efficient optical channel, maximizing the proportion of the light-transmitting area and reducing stray light interference; at the same time, the honeycomb structure enhances mechanical stability and avoids depth-of-field attenuation caused by lamination deformation.

[0014] As a further improvement to the above scheme, the high-reflectivity dielectric layer is composed of 5-8 pairs of alternating TiO2 and SiO2 layers, wherein the thickness of the TiO2 layer is 80-100nm and the thickness of the SiO2 layer is 100-120nm. The alternating stacking of TiO2 / SiO2 achieves high reflectivity, reduces light energy loss, effectively improves image brightness, and the multilayer dielectric structure is not easily oxidized, thus extending its lifespan.

[0015] As a further improvement to the above solution, the substrates for the focusing lens layer and the gradient refractive layer are biaxially oriented PET or flexible PVC, with a total thickness of 30-70 μm. The biaxially oriented PET or flexible PVC substrate combines high light transmittance with flexibility, balancing mechanical strength and optical path requirements. This avoids light attenuation due to excessive thickness or deformation due to excessive thinness, ensuring the stable operation of the optical path extension effect of the gradient refractive layer.

[0016] As a further improvement to the above scheme, the pits in the nano-scattering layer are arranged in a hexagonal close-packed pattern, with the center-to-center distance between adjacent pits being 1.2-1.5 times the pit diameter. The hexagonal close-packed pits achieve the highest filling density, effectively improve the uniformity of the scattering unit distribution, eliminate optical dead angles, make the scattered light field continuously and gradually change, enhance the natural transition of the sense of depth, and avoid the image discontinuity caused by the existing random arrangement.

[0017] As a further improvement to the above solution, a wear-resistant protective layer is also included, laminated onto the outer surface of the focusing lens layer, with a thickness of 3-8 μm. This layer is made of UV-curable acrylic resin with a refractive index of 1.49-1.52. The UV-curable acrylic resin layer matches the refractive index of the lens layer, reducing surface reflection loss. The 3-8 μm thickness protects the microlens structure from scratches, maintaining a long-lasting depth-of-field effect.

[0018] As a further improvement to the above scheme, the convex lens curvature radius of the focusing lens layer is 25-40μm, and the embossing depth is 8-15μm. By optimizing the convex lens curvature radius and embossing depth parameters, the initial light convergence accuracy is improved, laying the foundation for the optical path extension of the subsequent gradient refractive layer and avoiding depth-of-field blurring caused by aberrations.

[0019] As a further improvement to the above solution, the total thickness of the cat-eye membrane is 0.05-0.2 mm, wherein the thickness ratio of the light-absorbing isolation layer to the nano-scattering layer is 1:3-1:6. Setting an appropriate thickness ratio of the light-absorbing isolation layer to the nano-scattering layer ensures that the light-absorbing layer fully filters stray light, while the thickness of the scattering layer is sufficient to produce wide-angle diffusion.

[0020] As a further improvement to the above solution, a pressure-sensitive adhesive layer and a release paper layer are also included; the pressure-sensitive adhesive layer is laminated to the bottom surface of the high-reflectivity dielectric layer, with a thickness of 0.02-0.05 mm; the release paper layer is peelably laminated to the bottom surface of the pressure-sensitive adhesive layer. The pressure-sensitive adhesive layer uses a colloid with high light transmittance to meet optical requirements; the release paper protects the activity of the adhesive layer, allowing the cat-eye film to be directly adhered to the packaging box, ensuring ease of application.

[0021] A packaging box includes a cat-eye film with enhanced depth-of-field effect, as described above. Attaching the cat-eye film to the surface of the packaging box enhances the depth-of-field effect of the printed pattern, improving consumer recognition. Furthermore, the complex optical path design, combined with the packaging's adaptability, effectively enhances anti-counterfeiting performance and product premium potential.

[0022] Beneficial effects:

[0023] This invention overcomes the optical limitations of existing single-layer cat's eye films through the synergistic construction of a gradient refractive layer and a nano-scattering layer. The gradient layer extends the light refraction path and simulates deep parallax; the nano-scattering layer increases the diversity of the emitted light angle. Combined with the light-absorbing isolation layer to suppress stray light and the high-reflection layer to enhance brightness, it ensures enhanced depth-of-field effect and effectively improves anti-counterfeiting performance and product premium space. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the layered structure of the cat eye membrane in Example 1.

[0025] Figure 2The light-transmitting openings of the light-absorbing isolation layer in this embodiment 1 are arranged in a hexagonal grid pattern.

[0026] Figure 3 This is a perspective view of Embodiment 2;

[0027] Figure label:

[0028] H1, Packaging box; M1, Cat eye mask;

[0029] 1. Wear-resistant protective layer;

[0030] 2. Focusing lens layer;

[0031] 3. Gradient refractive layer;

[0032] 4. Light-absorbing isolation layer; 41. Light-transmitting opening;

[0033] 5. Nanoscale scattering layer;

[0034] 6. High-reflectivity dielectric layer;

[0035] 7. Pressure-sensitive adhesive layer;

[0036] 8. Release paper layer. Detailed Implementation

[0037] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only a part of the embodiments of the present utility model, and not all of them. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0038] In the description of this utility model, it should be understood that the term "several" means "at least one", and the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0039] Example 1:

[0040] like Figures 1-2As shown, this embodiment provides a cat's eye film with enhanced depth-of-field effect, comprising, from top to bottom, a focusing lens layer 2, a gradient refractive layer 3, a light-absorbing isolation layer 4, a nano-scattering layer 5, and a high-reflectivity medium layer 6. Specifically:

[0041] The focusing lens layer 2 has a thickness of 15-30 μm and a convex lens array with a diameter of 50-100 μm on its surface, with a lens center-to-center spacing of 60-120 μm. In this embodiment, the radius of curvature of the convex lenses in the focusing lens layer 2 is 25-40 μm, and the embossing depth is 8-15 μm. The microlens array can be fabricated using hot pressing or UV embossing processes. By optimizing the radius of curvature of the convex lenses and the embossing depth parameters, the initial light convergence accuracy is improved, laying the foundation for the optical path extension of the subsequent gradient refractive layer 3 and avoiding depth-of-field blurring caused by aberrations.

[0042] The thickness of the gradient refractive layer 3 is 20-40 μm, and its lens curvature radius decreases by 15%-25% along the thickness direction. It is also ≤5 μm off-axis from the focusing lens layer 2. The gradient refractive layer 3 can be made by gradient evaporation or co-extrusion molding process.

[0043] In this embodiment, the substrates of the focusing lens layer 2 and the gradient refractive layer 3 are biaxially oriented PET or flexible PVC, with a total thickness of 30-70 μm. The biaxially oriented PET or flexible PVC substrate combines high light transmittance with flexibility, balancing mechanical strength and optical path requirements, avoiding light attenuation due to excessive thickness or deformation due to excessive thinness, and ensuring the stable performance of the optical path extension effect of the gradient refractive layer 3.

[0044] The light-absorbing isolation layer 4 has a thickness of 0.5-2 μm and is provided with an array of light-transmitting openings 41 with an opening diameter of 20-40 μm. In this embodiment, the light-transmitting openings 41 of the light-absorbing isolation layer 4 are arranged in a hexagonal grid with a grid line width ≤3 μm and an alignment error between the opening area and the center of the focusing lens ≤2 μm. The light-absorbing isolation layer 4 can be fabricated using photolithography or laser etching processes. The hexagonal grid arrangement is precisely aligned with the center of the lens to form an efficient optical channel, maximizing the proportion of the light-transmitting area and reducing stray light interference. At the same time, the honeycomb structure enhances mechanical stability and avoids depth-of-field attenuation caused by lamination deformation.

[0045] The nano-scattering layer 5 has a thickness of 5-15 μm and a surface array of pits with a diameter of 600-900 nm and a depth of 200-500 nm. In this embodiment, the pits in the nano-scattering layer 5 are arranged in a hexagonal close-packed pattern, with the center-to-center distance between adjacent pits being 1.2-1.5 times the pit diameter. The nano-scattering layer 5 is fabricated using a nanoimprinting process. The hexagonal close-packed pits achieve the highest filling density, effectively improving the uniformity of the scattering unit distribution, eliminating optical dead angles, and enabling a continuous and gradual change in the scattered light field, enhancing the natural transition of depth perception and avoiding image distortion caused by existing random arrangements.

[0046] In this embodiment, the total thickness of the cat-eye membrane is 0.05-0.2 mm, wherein the thickness ratio of the light-absorbing isolation layer 4 to the nano-scattering layer 5 is 1:3-1:6. Setting an appropriate thickness ratio of the light-absorbing isolation layer 4 to the nano-scattering layer 5 ensures that the light-absorbing layer fully filters stray light, while the thickness of the scattering layer is sufficient to produce wide-angle diffusion.

[0047] The high-reflectivity dielectric layer 6 has a thickness of 0.8-1.2 μm and covers the bottom surface of the nano-scattering layer 5. In this embodiment, the high-reflectivity dielectric layer 6 is composed of 5-8 pairs of alternating stacked TiO2 and SiO2 layers, wherein the thickness of the TiO2 layer is 80-100 nm and the thickness of the SiO2 layer is 100-120 nm. The high-reflectivity dielectric layer 6 can be constructed using multilayer sputtering or evaporation processes. The alternating stacking of TiO2 / SiO2 achieves high reflectivity, reduces light energy loss, effectively improves image brightness, and the multilayer dielectric structure is less prone to oxidation, thus extending its lifespan.

[0048] In this embodiment, a wear-resistant protective layer 1 is also included, laminated to the outer surface of the focusing lens layer 2, with a thickness of 3-8 μm, and made of UV-curable acrylic resin with a refractive index of 1.49-1.52. The UV-curable acrylic resin layer matches the refractive index of the lens layer, reducing surface reflection loss. The 3-8 μm thickness protects the microlens structure from scratches and maintains a long-lasting depth-of-field effect.

[0049] In this embodiment, a pressure-sensitive adhesive layer 7 and a release paper layer 8 are also included. The pressure-sensitive adhesive layer 7 is laminated to the bottom surface of the high-reflectivity medium layer 6, and has a thickness of 0.02-0.05 mm. The release paper layer 8 is peelably laminated to the bottom surface of the pressure-sensitive adhesive layer 7. The pressure-sensitive adhesive layer 7 can be made of polyurethane adhesive, which has high light transmittance and meets optical requirements. The release paper protects the adhesive layer's activity, allowing the cat-eye film to be directly adhered to the packaging box, ensuring ease of application.

[0050] In specific applications, the cat-eye film achieves enhanced depth of field through the synergistic optical structure of the gradient refractive layer 3 and the nano-scattering layer 5. When light enters the focusing lens layer 2, it is first converged by the convex lens array. Upon entering the gradient refractive layer 3, its radius of curvature decreases gradually along the thickness direction, such as by 15%-25%, thereby causing non-uniform refraction of the light, significantly extending the optical path difference, and simulating a deeper level of longitudinal parallax.

[0051] Next, the refracted light penetrates the light-transmitting opening 41 of the light-absorbing isolation layer 4, suppressing stray light interference. Upon reaching the nano-scattering layer 5, the surface pit array scatters the light, increasing the angular diversity of the outgoing light and giving the image a continuous gradient effect from different viewing angles. After being reflected by the high-reflectivity medium layer 6, the scattered light passes through the nano-pits again to enhance diffuse reflection, forming a multi-layered optical path superposition. The extension of the optical path of the gradient refractive layer 3, combined with the wide-angle diffusion of the nano-scattering layer 5, significantly expands the visual depth range of the image. At the same time, the light-absorbing isolation layer 4 enhances contrast, and the high-reflectivity layer strengthens brightness, ultimately enhancing the depth-of-field effect.

[0052] Example 2:

[0053] like Figure 3 As shown, this is one embodiment of the present invention. The main technical solution of this embodiment is the same as that of Embodiment 1. Features not explained in this embodiment are explained in Embodiment 1 and will not be repeated here. The difference between this embodiment and Embodiment 1 is:

[0054] This embodiment provides a packaging box, including a cat-eye film with enhanced depth-of-field effect as described in Embodiment 1. Attaching the cat-eye film to the surface of the packaging box enhances the depth-of-field effect of the printed pattern on the box surface, improving consumer recognition. Furthermore, the complex optical path design, combined with the packaging's adaptability, effectively enhances anti-counterfeiting performance and product premium potential.

[0055] Based on the disclosure and teachings of the above specification, those skilled in the art can make changes and modifications to the above embodiments. Therefore, this utility model is not limited to the specific embodiments disclosed and described above, and some modifications and changes to the utility model should also fall within the protection scope of the claims of this utility model. Furthermore, although some specific terms are used in this specification, these terms are only for convenience of explanation and do not constitute any limitation on this utility model.

Claims

1. A cat-eye film with enhanced depth-of-field effect, characterized in that, Including those compounded sequentially from top to bottom: Focusing lens layer: with a thickness of 15-30μm, and a convex lens array with a diameter of 50-100μm on the surface, and a lens center-to-center distance of 60-120μm; Gradient refractive layer: with a thickness of 20-40μm, its lens curvature radius decreases by 15%-25% along the thickness direction, and its coaxial alignment offset with the focusing lens layer is ≤5μm; Light-absorbing isolation layer: 0.5-2μm thick, with an array of light-transmitting openings, the opening diameter being 20-40μm; Nano-scattering layer: 5-15μm thick, with an array of pits distributed on the surface, the pits having a diameter of 600-900nm and a depth of 200-500nm; High reflectivity medium layer: 0.8-1.2 μm thick, covering the bottom surface of the nano-scattering layer.

2. The cat-eye film with enhanced depth-of-field effect according to claim 1, characterized in that, The light-transmitting openings of the light-absorbing isolation layer are arranged in a hexagonal grid, with a grid line width ≤3μm and an alignment error between the opening area and the center of the focusing lens ≤2μm.

3. The cat-eye film with enhanced depth-of-field effect according to claim 1, characterized in that, The high-reflectivity dielectric layer is composed of 5-8 pairs of TiO2 layers and SiO2 layers stacked alternately, wherein the thickness of the TiO2 layer is 80-100nm and the thickness of the SiO2 layer is 100-120nm.

4. The cat-eye film with enhanced depth-of-field effect according to claim 1, characterized in that, The substrates for the focusing lens layer and the gradient refractive layer are biaxially oriented PET or flexible PVC, with a total thickness of 30-70 μm.

5. A cat-eye film with enhanced depth-of-field effect according to claim 1, characterized in that, The pits in the nano-scattering layer are arranged in a hexagonal close-packed pattern, with the center-to-center distance between adjacent pits being 1.2-1.5 times the pit diameter.

6. The cat-eye film with enhanced depth-of-field effect according to claim 1, characterized in that, It also includes a wear-resistant protective layer, which is laminated to the outer surface of the focusing lens layer, with a thickness of 3-8μm. The material is UV-curable acrylic resin with a refractive index of 1.49-1.

52.

7. A cat-eye film with enhanced depth-of-field effect according to claim 1, characterized in that, The convex lens curvature radius of the focusing lens layer is 25-40μm, and the embossing depth is 8-15μm.

8. A cat-eye film with enhanced depth-of-field effect according to claim 1, characterized in that, The total thickness of the cat-eye membrane is 0.05-0.2 mm, wherein the thickness ratio of the light-absorbing isolation layer to the nano-scattering layer is 1:3-1:

6.

9. A cat-eye film with enhanced depth-of-field effect according to claim 1, characterized in that, It also includes a pressure-sensitive adhesive layer and a release paper layer; the pressure-sensitive adhesive layer is laminated to the bottom surface of the high-reflectivity medium layer and has a thickness of 0.02-0.05 mm; the release paper layer is peelably laminated to the bottom surface of the pressure-sensitive adhesive layer.

10. A packaging box, characterized in that, Including a cat-eye film with enhanced depth-of-field effect as described in any one of claims 1-9.

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