Anti-reflection film for HUD and HUD glass
By using an anti-reflection film consisting of a thin film base layer, a one-way perspective layer, and an S-polarized light anti-reflection layer in the HUD system, the problem of privacy leakage caused by the projected image being transmitted outside the vehicle is solved. This allows the driver to see the projected image and the external environment inside the vehicle while preventing outsiders from seeing the projected image.
Patent Information
- Application Number
- CN202422394449.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-30
- Publication Date
- 2025-10-28
- Estimated Expiration
- 2034-09-30
AI Technical Summary
In existing HUD technology, the projected image is transmitted outside the vehicle, resulting in the driver's privacy being leaked.
An anti-reflection film for HUD is used, including a film base layer, a one-way perspective layer, an S-polarized light anti-reflection layer and a pressure-sensitive adhesive layer. The one-way perspective function of the one-way perspective layer is utilized to make the projected image visible only to the driver and invisible to people outside the vehicle.
It effectively prevents the projected image from being transmitted outside the vehicle, protects the driver's privacy, and ensures that the driver can view the projected image and the external environment normally in the vehicle.
Smart Images
Figure CN223481076U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to HUD technology, and more particularly to an anti-reflective film and HUD glass for HUDs. Background Technology
[0002] HUD stands for Head-Up Display. It's a technology that projects important information (such as vehicle speed, navigation information, and vehicle status) onto a transparent display panel in front of the driver, allowing the driver to see the information they need without looking down. In the automotive field, HUDs can project important information such as vehicle speed, navigation instructions, and safety warnings onto the windshield in front of the driver's line of sight, helping the driver maintain focus on the road and reducing distractions caused by looking down at the instrument panel or center console screen, thereby improving driving safety.
[0003] Because the windshield has a high light transmittance, part of the projected image is reflected by the windshield and viewed by the driver, while part is projected through the windshield and seen by people outside the vehicle, thus revealing the driver's driving route and destination, among other privacy information. Utility Model Content
[0004] To address the shortcomings of the existing technology, this invention provides an anti-reflective film for HUDs, which can prevent the projected image from being transmitted outside the vehicle and causing privacy leaks.
[0005] This utility model also provides a HUD glass, including the above-mentioned anti-reflective film for HUD.
[0006] The technical problem to be solved by this utility model is achieved through the following technical solution:
[0007] An anti-reflective film for HUD, comprising:
[0008] A thin film substrate having opposing first and second surfaces;
[0009] A one-way transparent layer is disposed on the first surface of the thin film base layer;
[0010] An S-polarized antireflection layer is disposed on the surface of the one-way transparent layer away from the film substrate;
[0011] A pressure-sensitive adhesive layer is disposed on the second surface of the film substrate.
[0012] Furthermore, the one-way transparent layer includes a high-reflectivity layer, which has a plurality of light-transmitting micropores evenly distributed thereon.
[0013] Furthermore, the high-reflectivity layer is a metal coating.
[0014] Furthermore, the thickness of the high-reflectivity layer is between 10 and 100 nm.
[0015] Furthermore, the pore size of the light-transmitting micropores is between 0.1 and 0.2 mm, and the porosity is between 10% and 30%.
[0016] Furthermore, the S-polarized antireflection layer comprises a first high refractive index layer, a first low refractive index layer, a medium refractive index layer, a second high refractive index layer, and a second low refractive index layer sequentially disposed on the surface of the unidirectional transparent layer.
[0017] Furthermore, the refractive indices of the first high refractive index layer and the second high refractive index layer are between 2.3 and 2.5, the refractive index of the intermediate refractive index layer is between 1.8 and 2.0, and the refractive indices of the first low refractive index layer and the second low refractive index layer are between 1.4 and 1.5.
[0018] Furthermore, the HUD antireflective film also includes a semi-reflective layer, which is disposed between the unidirectional transparent layer and the S-polarized antireflective layer.
[0019] A HUD glass includes a windshield and the aforementioned anti-reflective film for HUD, wherein the anti-reflective film for HUD is adhered and fixed to the surface of the windshield by the pressure-sensitive adhesive layer.
[0020] Furthermore, the windshield includes a first glass substrate, a PVB adhesive layer, and a second glass substrate, wherein the first glass substrate and the second glass substrate are bonded together by the PVB adhesive layer.
[0021] The present invention has the following beneficial effects: The HUD anti-reflective film of the present invention provides a one-way transparent layer between the thin film substrate and the S-polarized light anti-reflective layer. By utilizing the one-way transparent function of the one-way transparent layer, the driver can normally see the projected image on the S-polarized light anti-reflective layer and can see the road conditions outside the vehicle through the one-way transparent layer. However, people outside the vehicle cannot see the projected image on the S-polarized light anti-reflective layer through the one-way transparent layer, thereby avoiding the leakage of the driver's driving route and destination privacy. Attached Figure Description
[0022] Figure 1 This is a schematic diagram of the stacked structure of the antireflective film for HUD provided by this utility model.
[0023] Figure 2 This is a schematic diagram of the front structure of the one-way transparent layer in the anti-reflective film for HUD provided by this utility model.
[0024] Figure 3 This is a schematic diagram of the stacked structure of the S-polarized antireflection layer in the HUD antireflection film provided by this utility model.
[0025] Figure 4 This is a schematic diagram of the stacked structure of another anti-reflective film for HUD provided by this utility model.
[0026] Figure 5 This is a schematic diagram of the stacked structure of the HUD glass provided by this utility model. Detailed Implementation
[0027] The present invention will now be described in detail with reference to the accompanying drawings and embodiments, examples of which are shown in the drawings. Throughout the drawings, the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.
[0028] In the description of this utility model, it should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", 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 element 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.
[0029] Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first," "second," or "third" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "multiple" means two or more, unless otherwise explicitly specified.
[0030] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," "fixing," and "setting," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.
[0031] Example 1
[0032] like Figure 1 As shown, an anti-reflective film for HUD includes:
[0033] A thin film substrate having opposing first and second surfaces;
[0034] A one-way transparent layer 22 is disposed on the first surface of the thin film base layer;
[0035] S-polarized antireflection layer 23 is disposed on the surface of the one-way transparent layer 22 away from the film substrate;
[0036] Pressure-sensitive adhesive layer 24 is disposed on the second surface of the film base layer.
[0037] The HUD anti-reflective film of this invention provides a one-way transparent layer 22 between the thin film substrate and the S-polarized anti-reflective layer 23. Utilizing the one-way transparent function of the one-way transparent layer 22, the driver can normally see the projected image on the S-polarized anti-reflective layer 23 and can see the road conditions outside the vehicle through the one-way transparent layer 22. However, people outside the vehicle cannot see the projected image on the S-polarized anti-reflective layer 23 through the one-way transparent layer 22, thus avoiding the leakage of the driver's driving route and destination privacy.
[0038] The one-way perspective layer 22 is a film layer with one-way perspective function. Specifically, on both sides of the one-way perspective layer 22, the side with higher brightness can see the side with lower brightness through the one-way perspective layer 22, while the side with lower brightness cannot see the side with higher brightness through the one-way perspective layer 22. Therefore, by simply controlling the brightness of the light source of the HUD system so that the brightness of the projected image is lower than the brightness of the external environment, it is possible to ensure that people outside the vehicle cannot see the projected image on the S-polarized anti-reflection layer 23 through the one-way perspective layer 22, while the driver can see the road conditions outside the vehicle through the one-way perspective layer 22. Even at night, when there are streetlights and headlights and other lighting sources outside the vehicle, the brightness of the projected image, being lower than the brightness of the external environment, can still meet the driver's viewing requirements.
[0039] like Figure 2 As shown, the one-way transparent layer 22 includes a high reflective layer 221, and the high reflective layer 221 is provided with a plurality of light-transmitting micropores 222 evenly distributed.
[0040] The high reflectivity layer 221 ensures the high reflectivity of the one-way vision layer 22, while the light-transmitting micro-aperture 222 satisfies the partial transmittance of the one-way vision layer 22. Regardless of which side a beam of light passes through the one-way vision layer 22 from, most of the light will be reflected by the high reflectivity layer 221, while a small portion will pass through the high reflectivity layer 221 via the light-transmitting micro-aperture 222. On the side with higher brightness, the light reflected by the high-reflectivity layer 221 is much brighter than the light transmitted through the light-transmitting micro-aperture 222. The light reflected from the same side interferes with the light transmitted from the other side. Therefore, the side with lower brightness cannot be seen through the one-way perspective layer 22 on the side with higher brightness. On the side with lower brightness, even if only a small portion of the light from the other side passes through the light-transmitting micro-aperture 222 and the high-reflectivity layer 221, the light transmitted through the light-transmitting micro-aperture 222 is still brighter than the light reflected by the high-reflectivity layer 221 on the same side. Therefore, the side with higher brightness can be seen through the one-way perspective layer 22 on the side with lower brightness.
[0041] The high reflectivity layer 221 is preferably a metal coating, such as a silver coating or an aluminum coating, with a thickness between 10-100 nm; the light-transmitting micropores 222 have a pore size between 0.1-0.2 mm and a porosity between 10%-30%.
[0042] The film substrate may be, but is not limited to, PET film, PI film, or PC film.
[0043] The S-polarized antireflection layer 23 is used to reduce the reflectivity of S-polarized light in the projected image, and only reflect P-polarized light in the projected image to the driver for viewing, so as to alleviate the ghosting problem of the projected image after reflection.
[0044] like Figure 3 As shown, the S-polarized antireflection layer 23 includes a first high refractive index layer 231, a first low refractive index layer 232, a medium refractive index layer 233, a second high refractive index layer 234, and a second low refractive index layer 235 sequentially disposed on the surface of the one-way transparent layer 22.
[0045] The refractive indices of the first high refractive index layer 231 and the second high refractive index layer 234 are between 2.3 and 2.5, the refractive index of the intermediate refractive index layer 233 is between 1.8 and 2.0, and the refractive indices of the first low refractive index layer 232 and the second low refractive index layer 235 are between 1.4 and 1.5.
[0046] In this embodiment, the first high refractive index layer 231 and the second high refractive index layer 234 may be, but are not limited to, niobium pentoxide coatings. The thickness of the first high refractive index layer 231 may be between 7-10 nm, and the thickness of the second high refractive index layer 234 may be between 45-55 nm. The first low refractive index layer 232 and the second low refractive index layer 235 may be, but are not limited to, silicon dioxide coatings. The thickness of the first low refractive index layer 232 may be between 40-60 nm, and the thickness of the second low refractive index layer 235 may be between 85-115 nm. The intermediate refractive index layer 233 may be, but is not limited to, zinc oxide coatings, and its thickness may be between 70-90 nm.
[0047] The S-polarized antireflection layer 23 of this invention can significantly reduce the reflectivity of S-polarized light incident from one side of the second low-refractive-index layer 235. In particular, for S-polarized light incident at large angles of 60-70°, the S-polarized antireflection layer 23 can achieve a more significant antireflection effect. When applied to the inner surface of the front windshield glass, the inner surface of the front windshield glass has an average reflectivity of up to 5% for S-polarized light at an incident angle of 60-70° across the entire spectral range of 400-700 nm.
[0048] Example 2
[0049] As an optimization of Embodiment 1, in this embodiment, such as Figure 4 As shown, the HUD antireflective film also includes a semi-reflective layer 25, which is disposed between the one-way transparent layer 22 and the S-polarized antireflective layer 23.
[0050] The anti-reflective film for HUD of this invention utilizes a semi-reflective layer 25 located between the one-way transparent layer 22 and the S-polarized anti-reflective layer 23. This semi-reflective layer 25 enhances the emission of the projected image, thereby increasing the brightness of the projected image seen by the driver, while simultaneously reducing the brightness of the projected image reaching the one-way transparent layer 22. This allows the projected image reaching the one-way transparent layer 22 to maintain a greater brightness difference with the external environment.
[0051] Example 3
[0052] like Figure 5 As shown, a HUD glass includes a windshield 1 and an anti-reflective film 2 for HUD as described in Embodiment 1 or Embodiment 2. The anti-reflective film 2 for HUD is adhered and fixed to the surface of the windshield 1 by the pressure-sensitive adhesive layer 24.
[0053] The windshield 1 includes a first glass substrate 11, a PVB adhesive layer 12, and a second glass substrate 13, wherein the first glass substrate 11 and the second glass substrate 13 are bonded together by the PVB adhesive layer 12.
[0054] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present utility model and not to limit them. Although the present utility model has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solutions of the present utility model, and these modifications or equivalent substitutions cannot cause the modified technical solutions to deviate from the scope of the technical solutions of the present utility model.
Claims
1. An anti-reflective film for HUD, characterized in that, include: A thin film substrate having opposing first and second surfaces; A one-way transparent layer is disposed on the first surface of the thin film base layer; An S-polarized antireflection layer is disposed on the surface of the one-way transparent layer away from the film substrate; A pressure-sensitive adhesive layer is disposed on the second surface of the film base layer; The one-way transparent layer includes a high-reflectivity layer, which has a plurality of uniformly distributed light-transmitting micropores, and the high-reflectivity layer is a metal coating. The S-polarized antireflection layer includes a first high refractive index layer, a first low refractive index layer, a medium refractive index layer, a second high refractive index layer, and a second low refractive index layer sequentially disposed on the surface of the unidirectional transparent layer; the first high refractive index layer, the first low refractive index layer, the medium refractive index layer, the second high refractive index layer, and the second low refractive index layer are all corresponding coatings.
2. The anti-reflective film for HUD according to claim 1, characterized in that, The thickness of the high-reflectivity layer is between 10 and 100 nm.
3. The antireflective film for HUD according to claim 1, characterized in that, The pore size of the light-transmitting micropores is between 0.1 and 0.2 mm, and the porosity is between 10% and 30%.
4. The anti-reflective film for HUD according to claim 1, characterized in that, The refractive indices of the first high refractive index layer and the second high refractive index layer are between 2.3 and 2.5, the refractive index of the intermediate refractive index layer is between 1.8 and 2.0, and the refractive indices of the first low refractive index layer and the second low refractive index layer are between 1.4 and 1.
5.
5. The antireflective film for HUD according to claim 1, characterized in that, The HUD antireflective film also includes a semi-reflective layer, which is disposed between the unidirectional transparent layer and the S-polarized antireflective layer.
6. A HUD glass, characterized in that, The device includes a windshield and the anti-reflective film for a head-up display (HUD) as described in claim 1, wherein the anti-reflective film for the HUD is adhered and fixed to the surface of the windshield by the pressure-sensitive adhesive layer.
7. The HUD glass according to claim 6, characterized in that, The windshield includes a first glass substrate, a PVB adhesive layer, and a second glass substrate, which are bonded together by the PVB adhesive layer.