Highly reflective HUD film

Abstract

The utility model discloses a high-reflection HUD film which comprises a base material layer, a first optical adhesive layer, a hardening layer, a bonding layer, a P polarized light reflection increasing layer and a second optical adhesive layer. The base material layer is provided with a first surface and a second surface which are oppositely arranged; the first optical adhesive layer is coated on the first surface of the base material layer; the hardening layer is coated on the second surface of the base material layer; the bonding layer is coated on the surface of the hardening layer; the P polarized light reflection increasing layer is arranged on the surface of the bonding layer in a magnetron sputtering manner; the P polarized light reflection increasing layer enables the reflectivity of P polarized light with the incident angle ranging from 45 degrees to 60 degrees to range from 45% to 60%. And the second optical adhesive layer is coated on the surface of the P polarized light reflection increasing layer. According to the high-reflection HUD film provided by the utility model, through adding the P polarized light reflection increasing layer and constructing the structure of the P polarized light reflection increasing layer, the generation of ghosting is reduced or avoided, and the reflectivity of incident light at the HUD film is improved, so that an HUD picture is clearer.

Description

Technical Field

[0001] The utility model belongs to the technical field of film materials, and in particular relates to a high-reflection HUD film. Background Art

[0002] HUD, also known as head-up display, uses the principle of optical reflection to project important information onto the glass, eliminating the need for the driver to lower their head to observe. This helps avoid distractions while driving, and eliminates the need to look away for fear of speeding, making driving safer. HUD is primarily composed of a projection unit and a display medium. The projection unit integrates a projector, reflector, projection mirror, adjustment motor, and control unit. The HUD obtains information such as vehicle speed and navigation from the vehicle's data bus, outputs images on the projector, and uses the principle of optical emission to display the output images on the display medium, which can be transparent resin glass or the front windshield.

[0003] In the prior art, since the windshield of a car usually uses laminated glass of a certain thickness, the incident light emitted by the projector will be reflected on the inner and outer surfaces of the windshield, thereby generating two projected images on the inner and outer surfaces of the glass. The double image formed by the two projected images will affect the clarity of the image displayed by the HUD system.

[0004] To reduce the effects of ghosting, a HUD film is added between laminated glass to increase its reflectivity for P-light and minimize ghosting. However, the reflectivity of existing HUD films for P-light generally ranges from 10% to 20%. When a car is driving in brightly lit areas, the driver cannot clearly see the image information due to the film's low reflectivity, which affects driving safety. Furthermore, existing HUD films have poor adhesion and can peel off before being processed with the laminated glass, significantly impacting the yield of the finished product.

[0005] The information disclosed in this background technology section is only intended to increase the understanding of the overall background of the present invention, and should not be regarded as an admission or any form of suggestion that the information constitutes the prior art already known to those skilled in the art. Utility Model Content

[0006] The purpose of the utility model is to provide a highly reflective HUD film, which can improve the reflectivity of P-polarized light with an incident angle between 45° and 60° and reduce ghosting.

[0007] To achieve the above objectives, a specific embodiment of the present invention provides the following technical solution: a highly reflective HUD film comprising: a substrate layer, a first optical adhesive layer, a hardening layer, an adhesive layer, a P-polarized light-enhancing layer, and a second optical adhesive layer. The substrate layer has a first surface and a second surface disposed opposite each other; the first optical adhesive layer is coated on the first surface of the substrate layer; the hardening layer is coated on the second surface of the substrate layer; the adhesive layer is coated on the surface of the hardening layer; the P-polarized light-enhancing layer is magnetron sputtered on the surface of the adhesive layer; the P-polarized light-enhancing layer provides a reflectivity of 45% to 60% for P-polarized light with an incident angle between 45° and 60°; and the second optical adhesive layer is coated on the surface of the P-polarized light-enhancing layer.

[0008] In one or more embodiments of the present invention, the P-polarized light-enhancing reflection layer includes, in order from the direction away from the substrate layer: a first Nb2O5 layer, a NiCr layer, an Ag layer, a ZnO layer, and a second Nb2O5 layer. The first Nb2O5 layer is plated on the surface of the adhesive layer; the NiCr layer is plated on the surface of the first Nb2O5 layer; the Ag layer is plated on the surface of the NiCr layer; the ZnO layer is plated on the surface of the Ag layer; and the second Nb2O5 layer is plated on the surface of the ZnO layer.

[0009] In one or more embodiments of the present invention, the thickness of the first Nb2O5 layer is between 45 nm and 55 nm.

[0010] In one or more embodiments of the present invention, the thickness of the NiCr layer is between 0.5 nm and 1.5 nm.

[0011] In one or more embodiments of the present invention, the thickness of the Ag layer is between 20 nm and 35 nm.

[0012] In one or more embodiments of the present invention, the thickness of the ZnO layer is between 15 nm and 25 nm.

[0013] In one or more embodiments of the present invention, the thickness of the second Nb2O5 layer is between 10 nm and 25 nm.

[0014] In one or more embodiments of the present invention, the substrate layer is a PC substrate layer having a total light transmittance greater than or equal to 90%; and the thickness of the substrate layer is between 100 μm and 250 μm.

[0015] In one or more embodiments of the present invention, the hardened layer is an acrylic resin layer with a refractive index between 1.52 and 1.55; the thickness of the hardened layer is between 3 μm and 5 μm.

[0016] In one or more embodiments of the present invention, the adhesive layer is a Si layer; the thickness of the adhesive layer is between 1 nm and 3 nm.

[0017] Compared to existing technologies, the high-reflectivity HUD film of this utility model reduces the reflection of incident HUD light at the windshield-air interface by adding a P-polarized light-enhancing layer and constructing a P-polarized light-enhancing layer structure, thereby reducing or eliminating ghosting. It also improves the reflectivity of incident light at the HUD film, especially for light incident at angles between 45° and 60°, resulting in clearer HUD images. Furthermore, an adhesive layer and an optical adhesive layer prevent detachment between the film layers and improve the bonding strength between the HUD film and the windshield. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments recorded in the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

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

[0020] Figure 2 This is a schematic diagram of a P-polarized light reflection enhancement layer in one embodiment of the present invention;

[0021] Figure 3 This is a reflectivity curve diagram of the high-reflective HUD film of Example 1 of the present utility model to P-polarized light;

[0022] Figure 4 This is a reflectivity curve diagram of the high-reflective HUD film of Example 2 of the present utility model to P-polarized light;

[0023] Figure 5 This is a reflectivity curve diagram of the high-reflective HUD film of Example 3 of the present utility model to P-polarized light.

[0024] Description of main reference numerals:

[0025] 1-substrate layer, 2-first optical adhesive layer, 3-hardening layer, 4-adhesive layer, 5-P polarized reflection enhancement layer, 51-first Nb2O5 layer, 52-NiCr layer, 53-Ag layer, 54-ZnO layer, 55-second Nb2O5 layer, 6-second optical adhesive layer. DETAILED DESCRIPTION

[0026] In order to enable those skilled in the art to better understand the technical solutions of the present invention, the following will be combined with the drawings of the embodiments of the present invention to clearly and completely describe the technical solutions of the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of the present invention.

[0027] like Figure 1-5 As shown, a high-reflection HUD film in one embodiment of the present invention includes: a substrate layer 1, a first optical adhesive layer 2, a hardening layer 3, an adhesive layer 4, a P-polarized light reflection enhancement layer 5, and a second optical adhesive layer 6. The substrate layer 1 has a first surface and a second surface arranged opposite to each other. The first optical adhesive layer 2 is coated on the first surface of the substrate layer 1. The hardening layer 3 is coated on the second surface of the substrate layer 1. The adhesive layer 4 is coated on the surface of the hardening layer 3. The P-polarized light reflection enhancement layer 5 is magnetron sputtered on the surface of the adhesive layer 4. The P-polarized light reflection enhancement layer 5 makes the reflectivity of the P-polarized light with an incident angle between 45°-60° between 45% and 60%. The second optical adhesive layer 6 is coated on the surface of the P-polarized light reflection enhancement layer 5.

[0028] The incident angle of the light emitted by the HUD and the inner surface of the windshield is approximately 45°-60°. When the light is incident on the interface between the two media, if the reflection coefficient is zero, it can be said that there is no reflection phenomenon (full transmission). The incident angle of the light at which no reflection occurs is called the Brewster angle. Theoretically, the incident angle of the incident light of the car HUD is near the Brewster angle, and the reflectivity of the incident light is theoretically low. However, because the windshield is double-layer glass, when the incident light enters the glass from the air and then from the glass to the air, the transmission medium changes, and the incident light that should have been fully transmitted will be refracted twice at the inner surface and the outer surface of the windshield, resulting in double images on the screen projected by the HUD. In addition, because the reflectivity of the incident light of the HUD is low at the existing HUD film, the reflected light is relatively small, which further causes the HUD screen to be unclear.

[0029] In the above-mentioned embodiment, the high-reflective HUD film of the present invention, by adding a P-polarized light-reflection enhancement layer 5, reduces the reflection of the incident HUD light at the interface between the windshield and the air, thereby reducing or preventing the occurrence of ghosting. It also increases the reflectivity of the incident light at the HUD film, making the HUD image clearer.

[0030] In one embodiment, if Figure 2As shown, the P-polarized light-enhancing reflection layer 5 includes, in order from the direction away from the substrate layer 1, a first Nb2O5 layer 51, a NiCr layer 52, an Ag layer 53, a ZnO layer 54, and a second Nb2O5 layer 55. Specifically, the first Nb2O5 layer 51 is deposited on the surface of the adhesive layer 4; the NiCr layer 52 is deposited on the surface of the first Nb2O5 layer; the Ag layer 53 is deposited on the surface of the NiCr layer 52; the ZnO layer 54 is deposited on the surface of the Ag layer 53; and the second Nb2O5 layer 55 is deposited on the surface of the ZnO layer 54.

[0031] The P-polarized anti-reflection layer 5 minimizes the impact of changes in the transmission medium when the HUD's incident light passes from air to glass and then back to air. This allows the incident light to achieve or nearly achieve full transmission, with minimal or no double refraction between the inner and outer surfaces of the windshield. This prevents ghosting in the HUD's projected image. Furthermore, the reflectivity of the HUD film is increased, increasing the amount of reflected light and enhancing the clarity of the HUD image.

[0032] Furthermore, the thickness of the first Nb2O5 layer 51 is between 45 nm and 55 nm. The thickness of the NiCr layer 52 is between 0.5 nm and 1.5 nm. The thickness of the Ag layer 53 is between 20 nm and 35 nm. The thickness of the ZnO layer 54 is between 15 nm and 25 nm. The thickness of the second Nb2O5 layer 55 is between 10 nm and 25 nm.

[0033] In one embodiment, substrate layer 1 may be a PC (polycarbonate) layer. The thickness of substrate layer 1 ranges from 100 μm to 250 μm. To match the light transmittance of the HUD film, substrate layer 1 may have a total light transmittance greater than or equal to that of PC substrate layer 1.

[0034] A first optical adhesive layer 2 is coated on the first surface of the substrate layer 1. A second optical adhesive layer 6 is coated on the surface of the P-polarized light-reflection enhancement layer 5 facing away from the substrate. For example, the first and second optical adhesive layers 2 and 6 may be OCA optical adhesive layers. The first and second optical adhesive layers 2 and 6 can improve the adhesion of the HUD film between the double-layer windshield and prevent the film from falling off.

[0035] The hardened layer 3 is coated on the second surface of the substrate layer 1, and has a high bonding strength with the adhesive layer 4. Preferably, the hardened layer 3 is coated with an acrylic resin having a refractive index between 1.52 and 1.55. The thickness of the hardened layer 3 is between 3 μm and 5 μm, and the resulting hardened layer 3 can reach a thickness of 2H (750 g), thereby maintaining a high bonding strength with the adhesive layer 4 while improving the durability of the HUD film.

[0036] Adhesive layer 4 is a Si layer deposited on the surface of hardened layer 3 via a magnetron sputtering process. The thickness of adhesive layer 4 ranges from 1 nm to 3 nm. The provision of adhesive layer 4 improves the adhesion between hardened layer 3 and P-polarized anti-reflection layer 5, preventing the layers from peeling off.

[0037] The present invention will be further described below with reference to specific embodiments.

[0038] Example 1

[0039] The high-reflection HUD film includes, from top to bottom, a first optical adhesive layer 2, a substrate layer 1, a hardening layer 3, an adhesive layer 4, a P-polarized light-enhancing reflection layer 5, and a second optical adhesive layer 6.

[0040] The base layer 1 is a PC layer with a thickness of 100 μm. The hardening layer 3 is an acrylic resin layer with a thickness of 3 μm. The adhesive layer 4 is a Si layer with a thickness of 2 nm.

[0041] The P-polarized light reflection enhancement layer 5 includes, in order from the direction away from the substrate layer 1, a first Nb2O5 layer 51 with a thickness of 45nm, a NiCr layer 52 with a thickness of 1nm, an Ag layer 53 with a thickness of 20nm, a ZnO layer 54 with a thickness of 15nm and a second Nb2O5 layer 55 with a thickness of 13nm.

[0042] like Figure 3 As shown, at this coating thickness, the reflectivity of the HUD film for P-polarized light is 45%.

[0043] Example 2

[0044] The high-reflection HUD film includes, from top to bottom, a first optical adhesive layer 2, a substrate layer 1, a hardening layer 3, an adhesive layer 4, a P-polarized light-enhancing reflection layer 5, and a second optical adhesive layer 6.

[0045] The base layer 1 is a PC layer with a thickness of 125 μm. The hardening layer 3 is an acrylic resin layer with a thickness of 4 μm. The adhesive layer 4 is a Si layer with a thickness of 2 nm.

[0046] The P-polarized light reflection enhancement layer 5 includes, in order from the direction away from the substrate layer 1, a first Nb2O5 layer 51 with a thickness of 50nm, a NiCr layer 52 with a thickness of 1nm, an Ag layer 53 with a thickness of 25nm, a ZnO layer 54 with a thickness of 20nm and a second Nb2O5 layer 55 with a thickness of 15nm.

[0047] like Figure 4 As shown, at this coating thickness, the reflectivity of the HUD film for P-polarized light is 51%.

[0048] Example 3

[0049] The high-reflection HUD film includes, from top to bottom, a first optical adhesive layer 2, a substrate layer 1, a hardening layer 3, an adhesive layer 4, a P-polarized light-enhancing reflection layer 5, and a second optical adhesive layer 6.

[0050] The base layer 1 is a PC layer with a thickness of 188 μm. The hardening layer 3 is an acrylic resin layer with a thickness of 5 μm. The adhesive layer 4 is a Si layer with a thickness of 3 nm.

[0051] The P-polarized light reflection enhancement layer 5 includes, in order from the direction away from the substrate layer 1, a first Nb2O5 layer 51 with a thickness of 50nm, a NiCr layer 52 with a thickness of 1.5nm, an Ag layer 53 with a thickness of 30nm, a ZnO layer 54 with a thickness of 20nm and a second Nb2O5 layer 55 with a thickness of 20nm.

[0052] like Figure 5 As shown, at this coating thickness, the reflectivity of the HUD film for P-polarized light is 58.5%.

[0053] In summary, the high-reflective HUD film of the present invention, by adding and constructing a P-polarized light-enhancing layer 5, reduces the reflection of incident HUD light at the interface between the windshield and air, reducing or preventing ghosting. It also improves the reflectivity of incident light at the HUD film, particularly for light incident at angles between 45° and 60°, resulting in a clearer HUD image. Furthermore, the inclusion of an adhesive layer 4 and an optical adhesive layer prevents separation between the film layers and improves the bonding strength between the HUD film and the windshield.

[0054] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the present invention is defined by the appended claims, not the foregoing description, and all variations within the meaning and range of equivalents of the claims are intended to be encompassed within the present invention. Any reference sign in a claim should not be construed as limiting the claim to which it relates.

[0055] In addition, it should be understood that although this specification is described in terms of implementation methods, not every implementation method contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

Claims

1. A highly reflective HUD film, characterized in that: include: A substrate layer having a first surface and a second surface opposite to each other; A first optical adhesive layer is coated on the first surface of the substrate layer; a hardening layer, coated on the second surface of the substrate layer; an adhesive layer, coated on the surface of the hardened layer; A P-polarized light reflection enhancement layer is magnetron sputtered on the surface of the adhesive layer; the P-polarized light reflection enhancement layer makes the reflectivity of P-polarized light with an incident angle between 45° and 60° between 45% and 60%; and The second optical adhesive layer is coated on the surface of the P-polarized light reflection-enhancing layer.

2. The high-reflection HUD film according to claim 1, characterized in that: The P-polarized light reflection enhancement layer includes, in order from the direction away from the substrate layer: a first Nb2O5 layer, plated on the surface of the adhesive layer; A NiCr layer is plated on the surface of the first Nb2O5 layer; An Ag layer is plated on the surface of the NiCr layer; A ZnO layer is plated on the surface of the Ag layer; and The second Nb2O5 layer is plated on the surface of the ZnO layer.

3. The high-reflection HUD film according to claim 2, characterized in that: The thickness of the first Nb2O5 layer is between 45nm and 55nm.

4. The high-reflection HUD film according to claim 2, wherein: The thickness of the NiCr layer is between 0.5 nm and 1.5 nm.

5. The high-reflection HUD film according to claim 2, wherein: The thickness of the Ag layer is between 20 nm and 35 nm.

6. The high-reflection HUD film according to claim 2, wherein: The thickness of the ZnO layer is between 15 nm and 25 nm.

7. The high-reflection HUD film according to claim 2, wherein: The thickness of the second Nb2O5 layer is between 10 nm and 25 nm.

8. The high-reflection HUD film according to claim 1, wherein: The substrate layer is a PC substrate layer with a total light transmittance greater than or equal to 90%; the thickness of the substrate layer is between 100 μm and 250 μm.

9. The highly reflective HUD film according to claim 1, wherein: The hardened layer is an acrylic resin layer with a refractive index between 1.52 and 1.55; the thickness of the hardened layer is between 3 μm and 5 μm.

10. The high-reflection HUD film according to claim 1, wherein: The adhesive layer is a Si layer; the thickness of the adhesive layer is between 1 nm and 3 nm.

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