Hud film with microstructure and hud display device

Abstract

The utility model discloses a kind of HUD film and HUD display device with microstructure. HUD film with microstructure includes substrate layer, multiple convex structures and reflection layer. Multiple convex structures are protruded from the surface of the substrate layer to the direction away from the substrate layer, and multiple convex structures are sequentially arranged on the surface of the substrate layer along the width direction of the substrate layer;Wherein, each convex structure extends along the length direction of the substrate layer;Each convex structure has first inclined plane arranged from bottom to top;The included angle between the first inclined plane and the surface of the substrate layer is between 5°-15°, and the width of the first inclined plane is between 3μm-20μm;Reflection layer is arranged on the first inclined plane of the convex structure. HUD film and HUD display device with microstructure of the utility model will not produce ghosting, improve picture definition, especially the definition when projection light incidence angle is greater than 60°.

Description

Technical Field

[0001] This utility model belongs to the field of thin film technology, specifically relating to a HUD thin film with a microstructure and a HUD display device. Background Technology

[0002] A HUD (Head-Up Display) is an in-vehicle display system based on optical reflection technology. It projects key driving information directly onto the windshield in front of the driver, allowing them to view it without looking down, significantly improving driving convenience and safety. The system mainly consists of a projection unit and a display medium. The projection unit integrates components such as a projector, reflector, projection lens, adjustment motor, and control module. It acquires data such as vehicle speed and navigation in real time via the vehicle data bus and generates images. Utilizing the principle of optical reflection, the generated image is projected onto the display medium, which can be a special transparent resin glass or the windshield itself as the display interface.

[0003] Most current automotive windshields use a laminated glass structure. The thickness of this glass causes incident light from the projector to be reflected on both the inner and outer surfaces of the glass. Since the two beams of light are reflected parallel to each other, they form two projected images, resulting in ghosting and reducing the clarity of the HUD system's display. To suppress ghosting, a HUD film is often added between the laminated glass layers to improve the reflectivity of polarized light. However, with existing HUD films, when the incident angle of polarized light is greater than 60°, the reflectivity of the inner surface of the windshield significantly increases. At this point, the polarized light reflected from the inner surface of the glass and the polarized light reflected from the HUD film simultaneously enter the viewer's eye, causing ghosting and affecting driving safety.

[0004] The information disclosed in this background section is intended only to enhance the understanding of the overall background of this utility model and should not be construed as an admission or in any way implying that the information constitutes prior art known to those skilled in the art. Utility Model Content

[0005] The purpose of this invention is to provide a HUD film with a microstructure that can avoid ghosting and improve the image clarity of the HUD film.

[0006] To achieve the above objectives, a specific embodiment of this utility model provides a HUD film with a microstructure, comprising a substrate layer, multiple protrusions, and a reflective layer. The multiple protrusions protrude from the surface of the substrate layer in a direction away from the substrate layer, and are sequentially disposed on the surface of the substrate layer along its width direction; wherein each protrusion extends along the length direction of the substrate layer; each protrusion has a first inclined surface arranged from bottom to top; the angle between the first inclined surface and the surface of the substrate layer is between 5° and 15°, and the width of the first inclined surface is between 3 μm and 20 μm; the reflective layer is disposed on the first inclined surface of the protrusions.

[0007] In one or more embodiments of this utility model, the protruding structure is integrally formed with the substrate layer.

[0008] In one or more embodiments of this utility model, the raised structure is separately disposed from the substrate layer, a coating layer is disposed between the substrate layer and the reflective layer, and the coating layer is embossed to form the raised structure.

[0009] In one or more embodiments of this utility model, the reflective layer is a P-polarized light reflective layer.

[0010] In one or more embodiments of the present invention, the reflective layer includes a first Nb2O5 layer, a first AZO layer, an Ag layer, a NiCr layer, a second AZO layer, and a second Nb2O5 layer formed sequentially by magnetron sputtering on the first inclined surface.

[0011] In one or more embodiments of the present invention, the thickness of the first Nb2O5 layer is 10nm-20nm; and / or, the thickness of the second Nb2O5 layer is 10nm-20nm.

[0012] In one or more embodiments of the present invention, the thickness of the first AZO layer is 15nm-25nm; and / or, the thickness of the second AZO layer is 15nm-25nm.

[0013] In one or more embodiments of this utility model, the thickness of the Ag layer is 10nm-25nm.

[0014] In one or more embodiments of this utility model, the thickness of the NiCr layer is 0.5nm-1.5nm.

[0015] Compared with existing technologies, the HUD film with microstructure of this invention has multiple protrusions on the substrate layer, which prevents the reflected light at the first inclined surface from reflecting parallel to the reflected light at the windshield, and prevents the light reflected from the windshield from entering the human eye, thus eliminating ghosting and improving the projection clarity of the HUD film. Furthermore, the angle between the first inclined surface and the surface of the substrate layer is between 5° and 15°, and the width of the first inclined surface is between 3μm and 20μm, which further eliminates ghosting caused by polarized light and effectively prevents the formation of rainbow patterns, further improving the projection clarity of the HUD film.

[0016] Another specific embodiment of this utility model provides a HUD display device, which includes double-layer light-transmitting glass, a HUD film as described in any of the above embodiments, and a projection unit. The double-layer light-transmitting glass is inclined relative to the horizontal plane and the angle between the double-layer light-transmitting glass and the horizontal plane is 30°-45°; the HUD film is attached between the double-layer light-transmitting glass; the projection unit is disposed below the double-layer light-transmitting glass and is used to emit projection light onto the HUD film; the angle between the projection light and the normal of the double-layer light-transmitting glass is 50°-80°.

[0017] Compared with the prior art, the HUD display device of this utility model adopts a HUD film with a microstructure so that the reflected light at the first inclined surface and the reflected light at the double-layer transparent glass will not be reflected in parallel, and the angle between the projected light and the double-layer transparent glass is 50°-80°. The light reflected by the double-layer transparent glass will not enter the human eye, thus avoiding ghosting and improving the projection clarity of the HUD display device, especially the clarity when the incident angle of the projected light is greater than 60°. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a first schematic diagram of a HUD film with a microstructure in one embodiment of the present invention;

[0020] Figure 2 This is a second schematic diagram of a HUD film with a microstructure in one embodiment of the present invention; Figure 3 This is a schematic diagram of a HUD display device in one embodiment of the present invention;

[0021] Figure 4This is a schematic diagram illustrating the working principle of a HUD display device in one embodiment of the present invention.

[0022] Explanation of key figure labels:

[0023] 1-Substrate layer, 2-Protruding structure, 21-First inclined surface, 3-Reflective layer, 4-Double-layer transparent glass, 5-Projection unit. Detailed Implementation

[0024] To enable those skilled in the art to better understand the technical solutions in this disclosure, the technical solutions in the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this disclosure, and not all embodiments. Based on the embodiments in this disclosure, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of this disclosure.

[0025] like Figure 1 and Figure 2 As shown, a HUD film with a microstructure in one embodiment of the present invention includes a substrate layer 1, a plurality of protrusions 2, and a reflective layer 3. The plurality of protrusions 2 extend from the surface of the substrate layer 1 (i.e., along...). Figure 2 The multiple protruding structures 2 protrude along the width direction of the substrate layer 1 (in the X-axis direction). Figure 2 The protrusions 2 are sequentially disposed on the surface of the substrate layer 1 along the Z-axis direction. Each protrusion 2 extends along the length of the substrate layer 1. Figure 2 (In the Y-axis direction). Each protrusion 2 has a first inclined surface 21 that is inclined from bottom to top; the angle between the first inclined surface 21 and the surface of the substrate layer 1 is between 5° and 15°, and the width of the first inclined surface 21 is between 3μm and 20μm. The reflective layer 3 is disposed on the first inclined surface 21 of the protrusion 2.

[0026] In the above embodiment, the HUD film with microstructure is used in conjunction with a car windshield, with the side having the raised structure 2 facing the driver's direction. Currently, most car windshields use laminated glass, and its thickness causes the incident light emitted from the projector to be reflected on both the inner and outer surfaces of the glass. Furthermore, the two beams of light are reflected parallel to each other, forming two projected images and producing a ghosting phenomenon. This HUD film, by setting a microstructure composed of multiple raised structures 2 on the substrate layer 1, changes the reflection angle of light at the first inclined surface 21. Therefore, the reflection angle of light at the first inclined surface 21 is different from the reflection angle at the windshield. The two reflected light beams are not reflected parallel to each other, and the light reflected from the windshield does not enter the driver's eye. Thus, the HUD film with microstructure does not produce ghosting, improving the projection clarity of the HUD film, especially when the incident angle of polarized light is greater than 60°. In addition, the angle between the first inclined surface 21 and the surface of the substrate layer 1 is between 5° and 15°, and the width of the first inclined surface 21 is between 3μm and 20μm, which can further eliminate the ghosting caused by polarized light and effectively prevent the generation of rainbow patterns, thereby further improving the projection clarity of the HUD film.

[0027] In one embodiment, the raised structure 2 can be integrally formed with the substrate layer 1, that is, the raised structure 2 is part of the substrate layer 1, and the corresponding raised structure 2 is imprinted on the surface of the substrate layer 1 through an imprinting process. It is understood that when the raised structure 2 and the substrate layer 1 are integrally formed, they are made of the same material. In another embodiment, the substrate layer 1 and the raised structure 2 are separate. Specifically, the surface of the substrate layer 1 is provided with a coating layer, and the coating layer is imprinted into a corresponding shape to form the raised structure 2 through an imprinting process. When the raised structure 2 is formed by imprinting the coating layer, the raised structure 2 and the substrate layer 1 can be made of different materials. Preferably, the refractive index of the raised structure 2 is 1.52-1.55.

[0028] To ensure that the HUD film does not affect the light transmittance of the windshield, in one embodiment, the substrate layer 1 may be selected from, but is not limited to, a PET substrate (polyethylene terephthalate), a PC substrate (polycarbonate), or a TAC substrate (cellulose triacetate), and its thickness is 100μm-190μm. Preferably, the substrate layer 1 has a total light transmittance of 90% or more.

[0029] Since the projection light from the HUD projection unit 5 is typically P-polarized or S-polarized light, in one embodiment, the reflective layer 3 can be either a P-polarized or S-polarized reflective layer to accommodate different polarization types. The specific type of reflective layer 3 can be adjusted according to the applicable HUD system.

[0030] Taking P-polarized light as an example, the reflective layer 3 is a P-polarized light reflective layer. Specifically, the reflective layer 3 may include a first Nb2O5 layer, a first AZO layer, an Ag layer, a NiCr layer, a second AZO layer, and a second Nb2O5 layer formed sequentially by magnetron sputtering on the first inclined surface 21 of the protruding structure 2.

[0031] Specifically, the thickness of the first Nb₂O₅ layer is 10nm-20nm. The thickness of the second Nb₂O₅ layer is 10nm-20nm. The thickness of the first AZO layer is 15nm-25nm. The thickness of the second AZO layer is 15nm-25nm. The thickness of the Ag layer is 10nm-25nm. The thickness of the NiCr layer is 0.5nm-1.5nm.

[0032] By setting the above-mentioned layer structure, the reflective layer 3 can improve the reflectivity of polarized light, especially the reflectivity of P-polarized light, thereby ensuring the display effect of the HUD film.

[0033] In summary, the HUD film with microstructure of this invention has multiple protrusions 2 on the substrate layer 1, which prevents the reflected light at the first inclined surface 21 from being reflected parallel to the reflected light at the windshield, and prevents the light reflected from the windshield from entering the human eye, thus avoiding ghosting and improving the projection clarity of the HUD film. Furthermore, the angle between the first inclined surface 21 and the surface of the substrate layer 1 is between 5° and 15°, and the width of the first inclined surface 21 is between 3μm and 20μm, which can further eliminate ghosting caused by polarized light and effectively prevent the formation of rainbow patterns, further improving the projection clarity of the HUD film.

[0034] Another embodiment of this utility model discloses a HUD display device, such as... Figure 3 As shown, the HUD display device includes a double-layer transparent glass 4, a HUD film and a projection unit 5 as described in any of the above embodiments.

[0035] The double-layered transparent glass 4 is inclined relative to the horizontal plane at an angle of 30°-45°. It can be understood that the double-layered transparent glass 4 can be a car windshield, and its angle with the horizontal plane is also the angle with the driver's horizontal line of sight. A HUD film is disposed between the double-layered transparent glass 4, with the side of the HUD film having the raised structure 2 facing the driver. A projection unit 5 is disposed below the double-layered transparent glass 4, that is, below the driver-facing side of the double-layered transparent glass 4, and is used to emit projection light onto the HUD film. The projection light can be, for example, P-polarized light or S-polarized light. The angle between the projection light and the normal to the double-layered transparent glass 4 is 50°-80°.

[0036] Figure 4 This is a schematic diagram illustrating the working principle of a HUD film and HUD display device, such as... Figure 3As shown, the angle between the double-layered transparent glass 4 and the horizontal plane is defined as angle 1. The angle between the projected ray and the normal to the double-layered transparent glass 4, i.e., the angle of incidence of the projected ray, is defined as angle 2. The angle of incidence of the projected ray inside the glass after refraction is defined as angle 3. The angle between the first inclined surface 21 and the surface of the substrate layer 1 (i.e., the angle between the first inclined surface 21 and the double-layered transparent glass 4) is defined as angle 4. The angle between the projected ray after refraction by the glass and the first inclined surface 21 is defined as angle 5. The angle between the projected ray after reflection by the first inclined surface 21 and the inner surface of the double-layered transparent glass 4 is defined as angle 6. The angle between the projected ray and the inner surface of the glass when it exits is defined as angle 7. The angle between the projected ray directly reflected by the double-layered transparent glass 4 and the transmitted ray after reflection by the first inclined surface 21 exiting the double-layered transparent glass 4 is defined as angle 8.

[0037] The relationships between the various angles are as follows: According to the refraction formula n1sinθ2=n2sinθ3, the refractive index of light in air is n1=1, and the refractive index in glass is n2=1.52. When angle 2 is between 50° and 80°, angle 3=arcsin(sinθ2 / 1.52). Therefore, angle 3 is between 30° and 40°.

[0038] The relationship between angles 3, 4, and 5 is: angle 5 = angle 3 - angle 4.

[0039] The relationship between angles 3, 4 and 6 is: angle 6 = angle 3 - (2 × angle 4).

[0040] The relationship between angles 6 and 7 is: n1sinθ7 = n2sinθ6; angle 7 = arcsin(1.52sinθ6).

[0041] The relationship between angles 2, 7, and 8 is: angle 8 = angle 2 - angle 7.

[0042] The HUD film and HUD display device of this utility model will be further described below with reference to specific embodiments and comparative examples.

[0043] Example 1

[0044] Substrate layer 1 is a 100μm PC layer.

[0045] In the protrusion structure 2, the angle (angle 4) between the first inclined surface 21 and the substrate layer 1 is 5°; the width of the first inclined surface 21 is 10μm.

[0046] The thickness of the first Nb2O5 layer in the reflective layer 3 is 13 nm, the thickness of the first AZO layer is 15 nm, the thickness of the Ag layer is 15 nm, the thickness of the NiCr layer is 1 nm, the thickness of the second AZO layer is 60 nm, and the thickness of the second Nb2O5 layer is 15 nm.

[0047] The angle (angle 1) between the double-layered transparent glass 4 and the horizontal plane is 30°. The angle (angle 2) between the projected ray and the normal to the double-layered transparent glass 4 is 60°.

[0048] According to the above formula, we can obtain that angle 1 is 30°, angle 2 is 60°, angle 3 is 35°, angle 5 is 30°, angle 6 is 20°, angle 7 is 30°, and angle 8 is 30°.

[0049] The HUD film has a reflectivity of 24.7% for projected light, which is measured using an Olympus reflectometer.

[0050] Example 2

[0051] Substrate layer 1 is a 125μm PET layer.

[0052] In the protrusion structure 2, the angle (angle 4) between the first inclined surface 21 and the substrate layer 1 is 8°; the width of the first inclined surface 21 is 15μm.

[0053] The thickness of the first Nb2O5 layer in the reflective layer 3 is 18 nm, the thickness of the first AZO layer is 18 nm, the thickness of the Ag layer is 20 nm, the thickness of the NiCr layer is 1 nm, the thickness of the second AZO layer is 65 nm, and the thickness of the second Nb2O5 layer is 13 nm.

[0054] The angle (angle 1) between the double-layered transparent glass 4 and the horizontal plane is 40°. The angle (angle 2) between the projected ray and the normal to the double-layered transparent glass 4 is 75°.

[0055] According to the above formula, we can obtain the following angles: angle 1 is 40°, angle 2 is 75°, angle 3 is 39°, angle 5 is 31°, angle 6 is 23°, angle 7 is 36°, and angle 8 is 39°.

[0056] The HUD film has a reflectivity of 31.7% for projected light, which is data obtained by measuring the reflectivity using an Olympus reflectometer.

[0057] Comparative Example 1

[0058] The substrate layer is a 125μm PET layer; it has no protruding structure.

[0059] A 16nm thick Nb2O5 layer, a 16nm thick AZO layer, a 12nm thick Ag layer, a 1nm thick NiCr layer, a 65nm thick AZO layer, and a 16nm thick Nb2O5 layer are sequentially deposited on the substrate layer.

[0060] The angle (angle 1) between the double-layered transparent glass 4 and the horizontal plane is 35°; the angle (angle 2) between the projected light ray and the normal of the double-layered transparent glass 4 is 70°.

[0061] According to the above formula, we can obtain that angle 1 is 35°, angle 2 is 70°, angle 3 is 38°, angle 4 is 0°, angle 5 is 38°, angle 6 is 38°, angle 7 is 70°, and angle 8 is 0°.

[0062] The HUD film has a reflectivity of 18.1% for projected light. The double-layered transparent glass has a reflectivity of 7.98% for projected light. Therefore, the contrast between the two is too small, which will cause ghosting.

[0063] In summary, the HUD film and HUD display device with microstructure of this utility model have multiple protruding structures 2 on the substrate layer 1, so that the reflected light at the first inclined surface 21 and the reflected light at the double-layer light-transmitting glass 4 will not be reflected in parallel, and the angle between the projected light and the double-layer light-transmitting glass 4 is 50°-80°. The light reflected by the windshield will not enter the human eye, thus preventing ghosting and improving the projection clarity of the HUD film and HUD display device, especially the clarity when the incident angle of the projected light is greater than 60°.

[0064] It will be apparent to those skilled in the art that this disclosure is not limited to the details of the exemplary embodiments described above, and that this disclosure can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of this disclosure is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within this disclosure. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0065] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A HUD thin film with a microstructure, characterized in that, include: Substrate layer; Multiple protrusions extend from the surface of the substrate layer away from the substrate layer, and the multiple protrusions are sequentially disposed on the surface of the substrate layer along the width direction of the substrate layer; wherein, each protrusion extends along the length direction of the substrate layer; each protrusion has a first inclined surface that is inclined from bottom to top; the angle between the first inclined surface and the surface of the substrate layer is between 5° and 15°, and the width of the first inclined surface is between 3μm and 20μm; and A reflective layer is disposed on the first inclined surface of the protruding structure.

2. The HUD thin film with microstructure according to claim 1, characterized in that, The protruding structure is integrally formed with the substrate layer.

3. The HUD thin film with microstructure according to claim 1, characterized in that, The raised structure is separately disposed from the substrate layer, and a coating layer is disposed between the substrate layer and the reflective layer. The coating layer is embossed to form the raised structure.

4. The HUD thin film with microstructure according to claim 1, characterized in that, The reflective layer is a P-polarized light reflective layer.

5. The HUD film with microstructure according to claim 4, characterized in that, The reflective layer comprises a first Nb2O5 layer, a first AZO layer, an Ag layer, a NiCr layer, a second AZO layer, and a second Nb2O5 layer, which are sequentially formed by magnetron sputtering on the first inclined surface.

6. The HUD thin film with microstructure according to claim 5, characterized in that, The thickness of the first Nb2O5 layer is 10nm-20nm; and / or, the thickness of the second Nb2O5 layer is 10nm-20nm.

7. The HUD thin film with microstructure according to claim 5, characterized in that, The thickness of the first AZO layer is 15nm-25nm; and / or, the thickness of the second AZO layer is 15nm-25nm.

8. The HUD film with microstructure according to claim 5, characterized in that, The thickness of the Ag layer is 10nm-25nm.

9. The HUD thin film with microstructure according to claim 5, characterized in that, The thickness of the NiCr layer is 0.5nm-1.5nm.

10. A HUD display device, characterized in that, include: Double-layered transparent glass, inclined relative to the horizontal plane and with an angle of 30°-45° to the horizontal plane; The HUD film as described in any one of claims 1-9 is adhered between the double-layered transparent glass; and A projection unit is disposed below the double-layer transparent glass and is used to emit projection light onto the HUD film; the angle between the projection light and the normal of the double-layer transparent glass is 50°-80°.

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