Glass for head-up displays and head-up display systems

The laminated glass with a reflective coating for HUD systems addresses ghosting by optimizing P-polarized light reflection and reducing visible light reflectance, ensuring clear and safe HUD image display.

JP7809219B2Active Publication Date: 2026-01-30FUJIAN WANDA AUTOMOBILE GLASS IND
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Patent Information

Application Number
JP2024554208
Authority / Receiving Office
JP · JP
Patent Type
Patents
Current Assignee / Owner
Priority Date
2022-03-22
Filing Date
2023-03-22
Publication Date
2026-01-30
Estimated Expiration
2043-03-22

AI Technical Summary

Technical Problem

Current head-up display (HUD) glass systems suffer from ghosting issues due to misaligned reflections on laminated glass surfaces, which degrade the clarity of projected images.

Method used

A laminated glass design with a reflective coating that includes an internal barrier layer, an improvement layer, and a laminated structure of high and low refractive index layers, optimized for P-polarized light reflection, while maintaining low visible light reflectance, to eliminate ghosting and enhance image clarity.

Benefits of technology

The solution provides clear, ghost-free HUD images by enhancing P-polarized light reflectivity and reducing visible light reflectance, improving driving safety and experience by ensuring only the intended image is visible to the driver.

✦ Generated by Eureka AI based on patent content.

Smart Images

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Patent Text Reader

Abstract

A head-up display glass (100) and a head-up display system (1000) are provided. The head-up display glass (100) includes a laminated glass and a reflective coating (40). The laminated glass includes an outer glass sheet (10), a polymer interlayer (30), and an inner glass sheet (20). The reflective coating (40) includes a laminated inner barrier layer (41), an improvement layer (42), and at least one laminate structure (43). The inner barrier layer (41) can prevent the improvement layer (42) from being destroyed by alkali metal ions on the glass surface during heat treatment, and prevent the improvement layer (42) from being oxidized by oxygen diffusion. The improvement layer (42) can further improve the reflectance of the reflective coating (40) for P-polarized light, while keeping the reflectance of the reflective coating (40) for visible light low. As a result, when a driver inside a vehicle visually observes a reflected image on the head-up display glass (100), he or she can only observe the reflected image on the reflective coating (40), eliminating the visual ghost phenomenon. In addition, the visible light reflectance of this head-up display glass (100) is 15% or less, so no noticeable reflected shadows are observed inside the vehicle.
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Description

[Technical Field]

[0001] REFERENCE TO RELATED APPLICATIONS This application claims priority from Chinese Patent Application No. 202210282494.1, filed on March 22, 2022, for an invention entitled "Glass for Head-Up Display and Head-Up Display System," the entire contents of which are incorporated herein by reference.

[0002] The present application relates to the technical field of glass products, and in particular to glass for head-up displays and head-up display systems. [Background technology]

[0003] With the development of science and technology, head-up display (HUD) systems are becoming increasingly common in vehicles. Vehicle head-up display systems can display important driving information, such as speed, engine RPM, fuel economy, tire pressure, and navigation, as well as information from external smart devices, in real time within the driver's field of vision. This allows the driver to view driving information without lowering their head, reducing the driver's focus on the road ahead. Furthermore, because the driver no longer needs to adjust their eyes to view the road in the distance and nearby instruments, eye strain is reduced, significantly improving driving safety and enhancing the driving experience.

[0004] Currently, head-up display technology is mainly realized by two methods: light-emitting imaging and projection imaging. Projection imaging is a method of projecting an image using the head-up display glass itself or a separately installed optical element. Using the head-up display glass to reflect the projected image is the simplest method. Because typical head-up display glass is laminated glass, the light from the projection light source in the head-up display system is reflected as it passes through the two surfaces that come into contact with the air of the laminated glass. The reflected images on the two surfaces are misaligned, forming two interfering ghost images, which significantly limits the clarity of the projected image. Summary of the Invention

[0005] An object of the present application is to provide a head-up display glass and a head-up display system that can display clear images without ghosting.

[0006] The present application provides glass for head-up displays. The glass for head-up displays includes laminated glass and a reflective coating capable of reflecting P-polarized light. The laminated glass includes an outer glass sheet, a polymer interlayer, and an inner glass sheet, with the polymer interlayer sandwiched between the outer and inner glass sheets. The reflective coating includes a laminated internal barrier layer, an improvement layer, and at least one laminate structure. The internal barrier layer is provided on the surface of the inner glass sheet away from the polymer interlayer. The laminate structure includes a high refractive index layer and a low refractive index layer sequentially stacked in a direction away from the internal barrier layer. The refractive index of the high refractive index layer is 1.8 or greater, and the refractive index of the low refractive index layer is less than 1.7. The improvement layer is provided between the internal barrier layer and the laminate structure, or the improvement layer is provided between the high refractive index layer and the low refractive index layer.

[0007] The reflectance of the head-up display glass for P-polarized light incident at an incident angle θ is Y, where θ satisfies 60°≦θ≦75° and Y satisfies Y≧15%.

[0008] When θ satisfies 65°≦θ≦75°, Y satisfies Y≧20%, and when θ satisfies 70°≦θ≦75°, Y satisfies Y≧27%.

[0009] The reflectance of glass for head-up displays for visible light incident perpendicularly is 15% or less.

[0010] The material of the inner barrier layer includes at least one of oxides of Zn, Sn, Ti, Si, Al, Nb, Zr, Ni, Mg, Cr, and Ta elements and oxides of alloys thereof, or at least one of nitrides of Si, Al, Zr, B, and Ti elements and nitrides of alloys thereof.

[0011] The material of the improvement layer includes at least one of the elements Ni, Cr, Fe, Ti, Mo, Cu, Al, Au, Sn, Zr, In, Si, Nb, Ge, W, Ta, Pd, and Pt, and alloys thereof.

[0012] The element or alloy in the improved layer has a crystalline structure, and the thickness of the improved layer is 1 nm to 40 nm.

[0013] The element or alloy in the improved layer has an amorphous structure, and the thickness of the improved layer is 1 nm to 5 nm.

[0014] The reflective coating further includes an outer barrier layer disposed on a surface of the at least one laminate structure remote from the inner barrier layer.

[0015] The material of the outer barrier layer includes at least one of nitrides of Si, Al, Zr, Ti, B, and Ni elements and nitrogen oxides of alloys thereof.

[0016] The thickness of the outer barrier layer is 3 nm to 30 nm.

[0017] The refractive index of the inner glass pane differs from that of the polymer interlayer by no more than 0.1, and the refractive index of the outer glass pane differs from that of the polymer interlayer by no more than 0.1.

[0018] Among the Lab values ​​of the reflected color of the head-up display glass measured from the reflective coating side, the a value ranges from -8 to 3, and the b value ranges from -12 to 0.

[0019] The present application further provides glass for a head-up display. The glass for a head-up display includes laminated glass and a reflective coating capable of reflecting P-polarized light. The laminated glass includes an outer glass sheet, a polymer interlayer, and an inner glass sheet, and the polymer interlayer is sandwiched between the outer glass sheet and the inner glass sheet. The reflective coating includes a laminated improvement layer and at least one laminate structure, and the laminate structure includes: Inner glass plate The head-up display glass includes a high refractive index layer and a low refractive index layer sequentially stacked along a direction away from the reflectance layer, the high refractive index layer having a refractive index of 1.8 or more and the low refractive index layer having a refractive index of less than 1.7. The head-up display glass has a reflectance Y for P-polarized light incident at an incident angle θ, where θ satisfies 60°≦θ≦75° and Y satisfies Y≧15%.

[0020] The reflective coating further includes an inner barrier layer disposed on a surface of the inner glass pane remote from the polymer interlayer.

[0021] The material of the improved layer has a crystalline structure, and the thickness of the improved layer is 1 nm to 40 nm.

[0022] The material of the improved layer has an amorphous structure, and the thickness of the improved layer is 1 nm to 5 nm.

[0023] The material of the improvement layer includes at least one of the elements Ni, Cr, Fe, Ti, Mo, Cu, Al, Au, Sn, Zr, In, Si, Nb, Ge, W, Ta, Pd, and Pt, and alloys thereof.

[0024] Among the Lab values ​​of the reflected color of the head-up display glass measured from the reflective coating side, the a value ranges from -8 to 3, and the b value ranges from -12 to 0.

[0025] The present application further provides a head-up display system, which includes a projection light source for generating P-polarized light and the above-described head-up display glass, wherein the P-polarized light is projected onto a reflective coating.

[0026] This application provides a head-up display glass and a head-up display system. By adding an internal barrier layer and an improvement layer to the reflective coating, the internal barrier layer can prevent destruction of the improvement layer by alkali metal ions on the glass surface during heat treatment and prevent oxidation of the improvement layer due to oxygen diffusion. The improvement layer further improves the reflectivity of the reflective coating for P-polarized light while maintaining a low reflectivity of the reflective coating for visible light. The combined effect of the internal barrier layer, improvement layer, and laminated structure results in a reflective coating with high reflectivity for P-polarized light. Therefore, when a driver inside a vehicle visually observes the reflected image on the head-up display glass, they only see the reflected image of the reflective coating, eliminating the visual ghosting phenomenon. Furthermore, the visible light reflectivity of the head-up display glass of this application is less than 15%, preventing noticeable reflections from being observed inside the vehicle. [Brief explanation of the drawings]

[0027] In order to more clearly explain the technical solutions of the embodiments of the present application or the prior art, the following briefly introduces the drawings used in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present application, and those skilled in the art can obtain other drawings from these drawings without creative efforts. [Figure 1] 1 is a schematic configuration diagram of a vehicle equipped with a head-up display system according to an embodiment of the present invention. [Figure 2] FIG. 2 is a schematic configuration diagram of a head-up display system of the vehicle shown in FIG. [Figure 3] 3 is a schematic diagram showing a cross-sectional structure of a first embodiment of a head-up display glass in the head-up display system shown in FIG. 2. FIG. [Figure 4]FIG. 4 is a schematic diagram illustrating a first example of a reflective coating in the first embodiment of the head-up display glass shown in FIG. 3. [Figure 5] FIG. 4 is a schematic diagram illustrating a second example of a reflective coating in the first embodiment of the head-up display glass shown in FIG. 3. [Figure 6] FIG. 4 is a schematic diagram illustrating a third example of the reflective coating in the first embodiment of the head-up display glass shown in FIG. 3. [Figure 7] FIG. 4 is a schematic diagram illustrating a fourth example of the reflective coating in the first embodiment of the head-up display glass shown in FIG. 3. [Figure 8] FIG. 4 is a schematic diagram illustrating a fifth example of the reflective coating in the first embodiment of the head-up display glass shown in FIG. 3. [Figure 9] FIG. 4 is a schematic diagram illustrating a sixth example of the reflective coating in the first embodiment of the head-up display glass shown in FIG. 3. [Figure 10] FIG. 4 is a schematic diagram illustrating a first example of a reflective coating in the second embodiment of the head-up display glass shown in FIG. 3. [Figure 11] FIG. 4 is a schematic diagram illustrating a second example of a reflective coating in the second embodiment of the head-up display glass shown in FIG. 3. DETAILED DESCRIPTION OF THE INVENTION

[0028] Hereinafter, the technical solutions of the embodiments of the present application will be clearly and completely described with reference to the drawings of the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, but not all of the embodiments. Based on the embodiments of the present application, all other embodiments that can be obtained by those skilled in the art without creative efforts belong to the protection scope of the present application.

[0029] Referring to FIG. 1, FIG. 1 is a schematic diagram of a vehicle 1 equipped with a head-up display system 1000 according to an embodiment of the present invention.

[0030] The vehicle 1 includes a head-up display system 1000 and a vehicle body 2000. The head-up display system 1000 is provided in the vehicle body 2000 and is used to display important driving information such as speed, engine RPM, fuel economy, tire pressure, navigation, and information from an external smart device in real time within the driver's field of vision.

[0031] Referring to FIG. 2, FIG. 2 is a schematic configuration diagram of the head-up display system 1000 of the vehicle 1 shown in FIG.

[0032] The head-up display system 1000 includes a head-up display glass 100 and a projection light source 200. The head-up display glass 100 is attached to a vehicle body 2000, and the projection light source 200 is located inside the vehicle body 2000. The head-up display glass 100 has a first side surface 101 and a second side surface 102 that face each other. When the head-up display glass 100 is attached to a vehicle, the first side surface 101 faces the exterior of the vehicle, and the second side surface 102 faces the interior of the vehicle.

[0033] The projection light source 200 is mounted inside the vehicle and is used to generate P-polarized light. The P-polarized light is projected onto the second-side surface 102 of the head-up display glass 100, which faces the interior of the vehicle. Some of the P-polarized light is incident on the second-side surface 102 at an incident angle θ and reflected by the second-side surface 102, while some of the P-polarized light passes through the head-up display glass 100, reaches the first-side surface 101, and is reflected by the first-side surface 101. The second-side surface 102 of the head-up display glass 100, which faces the interior of the vehicle, has a relatively high P-polarized light reflectance, while the first-side surface 101, which faces the exterior of the vehicle, has a relatively low P-polarized light reflectance. Therefore, when a driver inside the vehicle visually observes a reflected image (HUD image) of the head-up display glass 100, only the reflected image of the second-side surface 102 is observed, thereby eliminating the visual ghost phenomenon.

[0034] Here, the projection light source 200 generating P-polarized light can be understood to mean that the projection light generated by the projection light source 200 contains at least 80% P-polarized light. The higher the proportion of P-polarized light in the projection light, the brighter and clearer the head-up display image will be, and the easier it will be to eliminate visual ghosting. The projection light generated by the projection light source 200 preferably contains at least 90% P-polarized light, and more preferably contains 100% P-polarized light, i.e., the projection light is essentially pure P-polarized light.

[0035] Referring to Fig. 3, Fig. 3 is a schematic diagram showing a cross-sectional structure of a first embodiment of the head-up display glass 100 in the head-up display system 1000 shown in Fig. 2. For convenience of explanation, the thickness direction of the head-up display glass 100 shown in Fig. 2 is defined as the X-axis direction.

[0036] The head-up display glass 100 includes a laminated glass and a reflective coating 40 capable of reflecting P-polarized light. The laminated glass includes an outer glass plate 10, a polymer interlayer 30, and an inner glass plate 20, arranged in that order along the X-axis direction, with the polymer interlayer 30 sandwiched between the outer glass plate 10 and the inner glass plate 20.

[0037] The outer glass sheet 10 has a first surface 11 and a second surface 12. The first surface 11 and the second surface 12 are opposed to each other. The second surface 12 faces the polymer interlayer 30. The first surface 11 is the interface between the outer glass sheet 10 and air, i.e., the surface 101 on the first side of the head-up display glass 100. The inner glass sheet 20 has a third surface 21 and a fourth surface 22. The third surface 21 and the fourth surface 22 are opposed to each other. The third surface 21 faces the polymer interlayer 30. The fourth surface 22 is away from the polymer interlayer 30. In one embodiment, the difference between the refractive index of the outer glass sheet 10 and the refractive index of the polymer interlayer 30 is 0.1 or less, and the difference between the refractive index of the inner glass sheet 20 and the refractive index of the polymer interlayer 30 is 0.1 or less.

[0038] The reflective coating 40 is provided on the fourth surface 22 of the inner glass plate 20. When the head-up display glass 100 is installed in a vehicle, the reflective coating 40 faces the interior of the vehicle. The surface of the reflective coating 40 away from the fourth surface 22 is the second surface 102. The reflectivity of the reflective coating 40 is relatively high for the P-polarized light emitted from the projection light source 200, and the P-polarized light reflectivity of the first surface 11 of the outer glass plate 10 is relatively low, thereby eliminating the visual ghost phenomenon.

[0039] In this embodiment, the reflectance of the head-up display glass 100 for P-polarized light incident at an incident angle θ is defined as Y. In one embodiment, when 60°≦θ≦75°, Y≧15%. In another embodiment, when 65°≦θ≦75°, Y≧20%. In another embodiment, when 70°≦θ≦75°, Y≧27%.

[0040] 4 to 9, FIG. 4 is a schematic diagram of a first example of the reflective coating 40 in the first embodiment of the head-up display glass 100 shown in FIG. 3. FIG. 5 is a schematic diagram of a second example of the reflective coating 40 in the first embodiment of the head-up display glass 100 shown in FIG. 3. FIG. 6 is a schematic diagram of a third example of the reflective coating 40 in the first embodiment of the head-up display glass 100 shown in FIG. 3. FIG. 7 is a schematic diagram of a fourth example of the reflective coating 40 in the first embodiment of the head-up display glass 100 shown in FIG. 3. FIG. 8 is a schematic diagram of a fifth example of the reflective coating 40 in the first embodiment of the head-up display glass 100 shown in FIG. 3. FIG. 9 is a schematic diagram of a sixth example of the reflective coating 40 in the first embodiment of the head-up display glass 100 shown in FIG. 3. The positive direction of the X-axis in the drawings is the direction away from the internal barrier layer 41.

[0041] In a first embodiment, the reflective coating 40 includes a stacked internal barrier layer 41, an improvement layer 42, and at least one laminated structure 43. The internal barrier layer 41 is provided on the fourth surface 22 of the inner glass sheet 20. The internal barrier layer 41 and the laminated structure 43 are sequentially stacked along a direction away from the internal barrier layer 41, i.e., along the positive direction of the X axis shown in the drawing, i.e., along a direction away from the outer glass sheet 10 at the fourth surface 22. Each laminated structure 43 includes a high refractive index layer 431 and a low refractive index layer 432 stacked in order to form a high refractive index layer / low refractive index layer structure. The refractive index of the high refractive index layer 431 is 1.8 or greater, and the refractive index of the low refractive index layer 432 is less than 1.7. In some embodiments, the refractive index of the high refractive index layer 431 is 2.0 or greater. In other embodiments, the refractive index of the high refractive index layer 431 is 2.2 or greater. As used herein, the term "lamination" includes direct contact and indirect contact.

[0042] During heat treatment, the internal barrier layer 41 of the reflective coating 40 can prevent destruction of the improvement layer 42 by alkali metal ions on the fourth surface 22 of the inner glass sheet 20 and prevent oxidation of the improvement layer 42 due to oxygen diffusion, which is advantageous for improving the thermal stability of the reflective coating 40. The material of the internal barrier layer 41 includes at least one of oxides of Zn, Sn, Ti, Si, Al, Nb, Zr, Ni, Mg, Cr, and Ta elements and oxides of alloys thereof, or at least one of nitrides of Si, Al, Zr, B, and Ti elements and nitrides of alloys thereof. Examples of the internal barrier layer 41 include an SiO2 layer (silicon oxide layer), ZnSnO x layer (zinc tin oxide layer), Si3N4 layer (silicon nitride layer), ZrSiN x layer (silicon and zirconium nitride). In one embodiment, the thickness of the inner barrier layer 41 is 3 nm or more, and in another embodiment, the thickness of the inner barrier layer 41 is 5 nm or more.

[0043] The improvement layer 42 has a certain degree of reflectivity for P-polarized light, and can further improve the P-polarized light reflectivity of the reflective coating 40 while maintaining a low visible light reflectivity of the reflective coating 40, thereby satisfying the requirements for a relatively high P-polarized light reflectivity and a relatively low visible light reflectivity of the head-up display glass 100. In one embodiment, the material of the improvement layer 42 includes at least one of Ni, Cr, Fe, Ti, Mo, Cu, Al, Au, Sn, Zr, In, Si, Nb, Ge, W, Ta, Pd, and Pt, and alloys thereof. Examples of the improvement layer 42 include an amorphous Si layer, a crystalline Si layer, a Ti layer, an Al layer, and a NiCr layer.

[0044] In one embodiment, the element or alloy in the improved layer 42 has a crystalline structure, and the thickness of the improved layer is 1 nm to 40 nm. The thickness of the improved layer 42 is preferably greater than 5 nm, and more preferably 10 nm to 30 nm. Examples of the improved layer 42 having a crystalline structure include Ti, Mo, Al, and Si.

[0045] In another embodiment, the element or alloy in the improved layer 42 has an amorphous structure, and the thickness of the improved layer 42 is 1 nm to 5 nm.

[0046] Compared with the improvement layer 42 having an amorphous structure, the improvement layer 42 having a crystalline structure has better optical properties and lower visible light reflectance, which can further improve the P-polarized light reflectance of the reflective coating 40 and obtain lower visible light reflectance and better visible light transmittance.

[0047] The material of the high refractive index layer 431 in the laminated structure 43 includes at least one of oxides of Zn, Sn, Ti, Nb, Zr, Ni, In, Al, Ce, W, Mo, Sb, and Bi elements and oxides of alloys thereof, or at least one of nitrides, nitrogen oxides, and nitrides of alloys thereof, and nitrogen oxides of Si, Al, Zr, Y, Ce, and La elements. xIn one embodiment, the thickness of the high refractive index layer 431 is 30 nm to 85 nm. In another embodiment, the thickness of the high refractive index layer 431 is 40 nm to 65 nm.

[0048] As can be understood, the high refractive index layer 431 can include one or more sub-layer structures, i.e., if the high refractive index layer 431 includes one sub-layer structure, the refractive index of this single sub-layer structure is 1.8 or more, and if the high refractive index layer 431 includes multiple sub-layer structures, the refractive index of each of the multiple sub-layer structures is 1.8 or more.

[0049] The material of the low refractive index layer 432 in the laminated structure 43 includes at least one of oxides of Si, Al, Zr, and B elements and oxides of alloys thereof. x In one embodiment, the thickness of the low refractive index layer 432 is 35 nm to 130 nm. In another embodiment, the thickness of the low refractive index layer 432 is 50 nm to 100 nm.

[0050] As can be appreciated, the low refractive index layer 432 can include one or more sub-layer structures, i.e., if the low refractive index layer 432 includes one sub-layer structure, the refractive index of this single sub-layer structure is less than 1.7, and if the low refractive index layer 432 includes multiple sub-layer structures, the refractive index of each of the multiple sub-layer structures is less than 1.7.

[0051] In some examples, as shown in Figures 4 and 5, the improvement layer 42 is provided between the internal barrier layer 41 and the stacked structure 43. When the reflective coating 40 has one stacked structure 43, the improvement layer 42 is located between the internal barrier layer 41 and the high refractive index layer 431 of the stacked structure 43, as shown in Figure 4. When the reflective coating 40 has multiple stacked structures 43, the improvement layer 42 is located between the internal barrier layer 41 and the first stacked structure 43 located in the positive direction of the X-axis from the internal barrier layer 41. When the reflective coating 40 has two stacked structures 43, as shown in Figure 5, the improvement layer 42 is located between the internal barrier layer 41 and the first stacked structure 43 located in the positive direction of the X-axis from the internal barrier layer 41. Specifically, the improvement layer 42 is located between the internal barrier layer 41 and the high refractive index layer 431 of the first stacked structure 43.

[0052] In other examples, as shown in FIGS. 6 to 9, the improvement layer 42 is provided in at least one stack structure 43. Specifically, the improvement layer 42 is provided between a high refractive index layer 431 and a low refractive index layer 432 of the stack structure 43. When the reflective coating 40 includes one stack structure 43, the improvement layer 42 is located between the high refractive index layer 431 and the low refractive index layer 432 of the stack structure 43, as shown in FIG. 6. When the reflective coating 40 includes multiple stack structures 43, in one case, the improvement layer 42 may be located between two adjacent stack structures 43. As shown in FIG. 7, when the reflective coating 40 includes two stack structures 43, the improvement layer 42 is located between the low refractive index layer 432 of the first stack structure 43 and the high refractive index layer 431 of the second stack structure 43, which are located in the positive direction of the X-axis from the internal barrier layer 41. In another case, the improvement layer 42 may be located between the high refractive index layer 431 and the low refractive index layer 432 of any one of the laminate structures 43 .

[0053] As shown in FIG. 8, the reflective coating 40 includes two laminated structures 43, and the improvement layer 42 is located between the high refractive index layer 431 and the low refractive index layer 432 of the first laminated structure 43, which is located in the positive direction of the X-axis from the inner barrier layer 41.

[0054] As shown in FIG. 9, the reflective coating 40 includes two laminated structures 43, and the improvement layer 42 is located between the high refractive index layer 431 and the low refractive index layer 432 of the second laminated structure 43, facing in the positive direction of the X-axis from the inner barrier layer 41.

[0055] In the reflective coating 40 of the head-up display glass 100 according to the embodiment of the present application, the inner barrier layer 41 prevents destruction of the improvement layer 42 in the reflective coating 40 by alkali metal ions on the inner glass plate 20, and also prevents oxidation of the improvement layer 42 due to oxygen diffusion. The combined use of the improvement layer 42 and the laminated structure 43 further improves the P-polarized light reflectivity of the reflective coating 40, preventing visual ghosting when P-polarized light is projected onto the head-up display glass 100. The reflective coating 40 also maintains a relatively high visible light transmittance and a relatively low visible light reflectance, allowing the head-up display glass 100 to meet the requirements for safe driving, with no obvious reflection observed from inside the vehicle.

[0056] 10 and 11, Fig. 10 is a schematic configuration diagram of a first example of the reflective coating 40 in the second embodiment of the head-up display glass 100 shown in Fig. 3. Fig. 11 is a schematic configuration diagram of a second example of the reflective coating 40 in the second embodiment of the head-up display glass 100 shown in Fig. 3.

[0057] The reflective coating 40 in the second embodiment differs from the reflective coating 40 in the first embodiment in that the reflective coating 40 in the second embodiment further includes an outer barrier layer 44. That is, in the second embodiment, the reflective coating 40 includes an inner barrier layer 41, an improvement layer 42, at least one laminated structure 43, and the outer barrier layer 44. The inner barrier layer 41, the laminated structure 43, and the outer barrier layer 44 are sequentially laminated along the positive direction of the X-axis, i.e., the direction away from the outer glass sheet 10 at the fourth surface 22.

[0058] In this example, the external barrier layer 44 is provided on the side away from the internal barrier layer 41 of the outermost stacked structure 43, facing away from the internal barrier layer 41 in the positive direction of the X-axis. That is, the external barrier layer 44 is provided on the surface of the low refractive index layer 432 of the outermost stacked structure 43, facing away from the internal barrier layer 41. As shown in FIG. 10 , the reflective coating 40 of this example includes one stacked structure 43. The external barrier layer 44 is provided on the surface of the low refractive index layer 432 of the stacked structure 43, facing away from the internal barrier layer 41. As shown in FIG. 11 , the reflective coating 40 of this example includes two stacked structures 43. The external barrier layer 44 is provided on one side of the outermost stacked structure 43, facing away from the internal barrier layer 41 in the positive direction of the X-axis, facing away from the internal barrier layer 41. Specifically, the external barrier layer 44 is provided on the surface of the low refractive index layer 432 of the second stacked structure 43, facing away from the internal barrier layer 41 in the positive direction of the X-axis.

[0059] During heat treatment, the external barrier layer 44 of the reflective coating 40 is advantageous for improving the thermal stability of the reflective coating 40, preventing oxidation of the improvement layer 42 in the reflective coating 40, and improving the mechanical and chemical stability of the reflective coating 40. In one embodiment, the material of the external barrier layer 44 includes at least one of nitrides of Si, Al, Zr, Ti, B, and Ni elements and nitrogen oxides of their alloys. Examples of the external barrier layer 44 include a silicon nitride layer (SiN). A silicon nitride layer doped with Al or Zr is preferred as the external barrier layer 44. In one embodiment, the thickness of the external barrier layer 44 is 3 nm to 30 nm. A thickness of the external barrier layer 44 greater than 30 nm avoids affecting the P-polarized light reflectivity or the color of the reflective appearance.

[0060] In the reflective coating 40 of the head-up display glass 100 of this embodiment, the external barrier layer 44 blocks oxygen in the environment from penetrating into the reflective coating 40, thereby preventing oxidation of the improvement layer 42 in the reflective coating 40, improving the mechanical and chemical stability of the reflective coating 40, and maintaining a relatively high P-polarized light reflectance and a relatively low visible light reflectance of the reflective coating 40, so that the head-up display glass 100 can meet the requirements of automotive glass.

[0061] Examples 1-7 and Comparative Examples 1-4

[0062] Example 1

[0063] Example 1 provides a head-up display glass 100 including an outer glass sheet 10, a polymer interlayer 30, an inner glass sheet 20, and a reflective coating 40, which are laminated in this order. The reflective coating 40 of this example employs the configuration of the first example of the reflective coating 40 of Example 2. Specifically, the head-up display glass 100 can be formed by sequentially depositing the structure of the reflective coating 40 on the inner glass sheet 20, then forming it according to a high-temperature (550 to 650°C) forming process for automotive glass, next sandwiching the polymer interlayer 30 between the inner glass sheet 20 and the outer glass sheet 10, and finally performing high-pressure compression bonding.

[0064] The reflective coating 40 includes an inner barrier layer 41, an improvement layer 42, a high refractive index layer 431, a low refractive index layer 432, and an outer barrier layer 44, which are sequentially stacked on the fourth surface 22 of the inner glass sheet 20 in a direction away from the outer glass sheet 10, i.e., in a direction from the inner glass sheet 20 toward the interior of the vehicle. In this embodiment, the high refractive index layer 431 and the low refractive index layer 432 jointly form a laminated structure 43, and the improvement layer 42 is provided between the inner barrier layer 41 and the laminated structure 43.

[0065] The outer glass plate 10 and the inner glass plate 20 are both ordinary transparent glass (clear glass with a visible light transmittance of 70% or more) and each have a thickness of 2.1 mm. The polymer interlayer 30 is polyvinyl butyral (PVB) and has a thickness of 0.76 mm. The inner barrier layer 41 is a Si3N4 layer and has a thickness of 10 nm. The improvement layer 42 is a NiCr layer and has a thickness of 1.5 nm. The high refractive index layer 431 in the laminate structure 43 is TiO x The low refractive index layer 432 in the stacked structure 43 is a SiO2 layer and has a thickness of 72 nm. The outer barrier layer 44 is a Si3N4 layer and has a thickness of 10 nm.

[0066] <Example 2>

[0067] Example 2 provides a head-up display glass 100 including an outer glass sheet 10, a polymer interlayer 30, an inner glass sheet 20, and a reflective coating 40, which are laminated in this order. Both the outer glass sheet 10 and the inner glass sheet 20 are ordinary transparent glass (clear glass with a visible light transmittance of 70% or more) and each have a thickness of 2.1 mm. The polymer interlayer 30 is polyvinyl butyral (PVB) and has a thickness of 0.76 mm.

[0068] The reflective coating 40 includes an inner barrier layer 41, a high refractive index layer 431, an improvement layer 42, a low refractive index layer 432, and an outer barrier layer 44, which are laminated in this order on the fourth surface 22 of the inner glass sheet 20 along a direction away from the outer glass sheet 10, i.e., along a direction from the inner glass sheet 20 toward the interior of the vehicle. In this embodiment, the high refractive index layer 431 and the low refractive index layer 432 together form a laminated structure 43, and the improvement layer 42 is provided within the laminated structure 43.

[0069] The inner barrier layer 41 is a Si3N4 layer with a thickness of 33 nm. The high refractive index layer 431 is a TiO xThe outer barrier layer 44 is a SiN layer and has a thickness of 6.5 nm. The improvement layer 42 is a NiCr layer and has a thickness of 1.9 nm. The low refractive index layer 432 is a SiO layer and has a thickness of 86 nm. The outer barrier layer 44 is a SiN layer and has a thickness of 6.5 nm.

[0070] Example 3

[0071] Example 3 provides a glass 100 for a head-up display. The difference from Example 2 is that the reflective coating 40 in the glass 100 for a head-up display of Example 3 does not include an outer barrier layer 44. The reflective coating 40 of this example employs the configuration of the third example of the reflective coating 40 in Example 1 described above.

[0072] The reflective coating 40 includes an inner barrier layer 41, a high refractive index layer 431, an improvement layer 42, and a low refractive index layer 432, which are stacked in this order on the fourth surface 22 of the inner glass sheet 20 along a direction away from the outer glass sheet 10, i.e., along a direction from the inner glass sheet 20 toward the interior of the vehicle. In this embodiment, the high refractive index layer 431 and the low refractive index layer 432 jointly form a laminated structure 43, and the improvement layer 42 is provided within the laminated structure 43.

[0073] Example 4

[0074] Example 4 provides a head-up display glass 100 including an outer glass sheet 10, a polymer interlayer 30, an inner glass sheet 20, and a reflective coating 40, which are laminated in this order. The reflective coating 40 includes an inner barrier layer 41, a high refractive index layer 431, an improvement layer 42, a low refractive index layer 432, and an outer barrier layer 44, which are laminated in this order on the fourth surface 22 of the inner glass sheet 20 along a direction away from the outer glass sheet 10, i.e., along a direction from the inner glass sheet 20 toward the interior of the vehicle.

[0075] The outer glass plate 10 and the inner glass plate 20 are both made of ordinary transparent glass (clear glass with a visible light transmittance of 70% or more) and each have a thickness of 2.1 mm. The polymer interlayer 30 is made of polyvinyl butyral (PVB) and has a thickness of 0.76 mm. The inner barrier layer 41 is a Si3N4 layer and has a thickness of 28 nm. The high refractive index layer 431 is made of TiO x The outer barrier layer 44 is a SiN layer and has a thickness of 10 nm. The improvement layer 42 is a Ti layer and has a thickness of 3.5 nm. The low refractive index layer 432 is a SiO layer and has a thickness of 75 nm. The outer barrier layer 44 is a SiN layer and has a thickness of 10 nm.

[0076] <Example 5>

[0077] Example 5 provides a head-up display glass 100 including, laminated in sequence, an outer glass sheet 10, a polymer interlayer 30, an inner glass sheet 20, and a reflective coating 40. The reflective coating 40 includes, laminated in sequence on the fourth surface 22 of the inner glass sheet 20 along a direction away from the outer glass sheet 10, i.e., along a direction from the inner glass sheet 20 toward the interior of the vehicle, an inner barrier layer 41, a high refractive index layer 431, an improvement layer 42, a low refractive index layer 432, and an outer barrier layer 44.

[0078] The outer glass plate 10 and the inner glass plate 20 are both made of ordinary transparent glass (clear glass with a visible light transmittance of 70% or more) and each have a thickness of 2.1 mm. The polymer interlayer 30 is made of polyvinyl butyral (PVB) and has a thickness of 0.76 mm. The inner barrier layer 41 is a Si3N4 layer and has a thickness of 42 nm. The high refractive index layer 431 is made of TiO x The outer barrier layer 44 is a SiN layer and has a thickness of 12 nm. The improvement layer 42 is an Al layer and has a thickness of 2 nm. The low refractive index layer 432 is a SiO layer and has a thickness of 62 nm. The outer barrier layer 44 is a SiN layer and has a thickness of 12 nm.

[0079] Example 6

[0080] Example 6provides a head-up display glass 100 including an outer glass sheet 10, a polymer interlayer 30, an inner glass sheet 20, and a reflective coating 40, which are laminated in this order. The reflective coating 40 includes an inner barrier layer 41, an improvement layer 42, a high refractive index layer 431, a low refractive index layer 432, and an outer barrier layer 44, which are laminated in this order on the fourth surface 22 of the inner glass sheet 20 along a direction away from the outer glass sheet 10, i.e., along a direction from the inner glass sheet 20 toward the interior of the vehicle. The reflective coating 40 of this embodiment adopts the configuration of the first example of the reflective coating 40 in the second embodiment described above.

[0081] The outer glass plate 10 and the inner glass plate 20 are both made of ordinary transparent glass (clear glass with a visible light transmittance of 70% or more) and each have a thickness of 2.1 mm. The polymer interlayer 30 is made of polyvinyl butyral (PVB) and has a thickness of 0.76 mm. The inner barrier layer 41 is a Si3N4 layer and has a thickness of 52 nm. The improvement layer 42 is an amorphous Si layer and has a thickness of 3.2 nm. The high refractive index layer 431 is made of TiO x The low refractive index layer 432 is a SiO2 layer and has a thickness of 98 nm. The outer barrier layer 44 is a Si3N4 layer and has a thickness of 5 nm.

[0082] Example 7

[0083] Example 7 provides a head-up display glass 100 including an outer glass sheet 10, a polymer interlayer 30, an inner glass sheet 20, and a reflective coating 40, which are laminated in this order. The reflective coating 40 includes an inner barrier layer 41, an improvement layer 42, a high refractive index layer 431, a low refractive index layer 432, and an outer barrier layer 44, which are laminated in this order on the fourth surface 22 of the inner glass sheet 20 along a direction away from the outer glass sheet 10, i.e., along a direction from the inner glass sheet 20 toward the interior of the vehicle. The reflective coating 40 of this embodiment adopts the configuration of the first example of the reflective coating 40 in the second embodiment described above.

[0084] The outer glass plate 10 and the inner glass plate 20 are both ordinary transparent glass (clear glass with a visible light transmittance of 70% or more) and each have a thickness of 2.1 mm. The polymer interlayer 30 is polyvinyl butyral (PVB) and has a thickness of 0.76 mm. The inner barrier layer 41 is a Si3N4 layer and has a thickness of 50 nm. The improvement layer 42 is a crystalline Si layer and has a thickness of 26 nm. The high refractive index layer 431 is TiO x The low refractive index layer 432 is a SiO2 layer and has a thickness of 49 nm. The outer barrier layer 44 is a Si3N4 layer and has a thickness of 12 nm.

[0085] <Comparative Example 1>

[0086] Comparative Example 1 provides a head-up display glass comprising an outer glass sheet, a polymer interlayer, an inner glass sheet, and a reflective coating, which are laminated in sequence. The reflective coating comprises a high refractive index layer and a low refractive index layer, which are laminated in sequence, and the high refractive index layer is bonded to the inner glass sheet. The reflective coating does not have an inner barrier layer, an improvement layer, or an outer barrier layer.

[0087] The outer and inner glass plates are both made of ordinary transparent glass (clear glass with a visible light transmittance of 70% or higher) and are 2.1 mm thick. The polymer interlayer is made of polyvinyl butyral (PVB) and is 0.76 mm thick. The high refractive index layer is made of TiO x The low refractive index layer is a SiO2 layer and has a thickness of 103 nm.

[0088] <Comparative Example 2>

[0089] Comparative Example 2 provides a head-up display glass including an outer glass sheet, a polymer interlayer, an inner glass sheet, and a reflective coating, which are laminated in this order. The reflective coating includes a high refractive index layer and a low refractive index layer, which are laminated in this order, and the high refractive index layer is attached to the inner glass sheet. The reflective coating does not include an inner barrier layer, an improvement layer, or an outer barrier layer.

[0090] The outer and inner glass plates are both made of ordinary transparent glass (clear glass with a visible light transmittance of 70% or higher) and are 2.1 mm thick. The polymer interlayer is made of polyvinyl butyral (PVB) and is 0.76 mm thick. The high refractive index layer is made of TiO x The low refractive index layer is a SiO2 layer and has a thickness of 98 nm.

[0091] <Comparative Example 3>

[0092] A head-up display glass is provided in Comparative Example 3. The difference from the head-up display glass 100 of Example 1 is that the head-up display glass of Comparative Example 3 does not have the inner barrier 41.

[0093] <Comparative Example 4>

[0094] Comparative Example 4 provides a head-up display glass including an outer glass sheet, a polymer interlayer, an inner glass sheet, and a reflective coating, which are laminated in this order. The reflective coating includes an inner barrier layer, a high refractive index layer, a low refractive index layer, an improvement layer, and an outer barrier layer, which are laminated in this order on the surface of the inner glass sheet in a direction away from the outer glass sheet, i.e., in a direction from the inner glass sheet toward the interior of the vehicle. The high refractive index layer and the low refractive index layer in Comparative Example 4 jointly form a laminated structure, and the improvement layer is provided between the laminated structure and the outer barrier layer.

[0095] The outer and inner glass panes were both 2.1 mm thick and made of standard clear glass (clear glass with a visible light transmittance of 70% or higher). The polymer interlayer was made of polyvinyl butyral (PVB) and had a thickness of 0.76 mm.

[0096] The inner barrier layer is a Si3N4 layer with a thickness of 7 nm. The high refractive index layer is a TiO xThe low refractive index layer is a SiO2 layer and has a thickness of 92 nm. The improvement layer is a NiCr layer and has a thickness of 1.5 nm. The outer barrier layer is a Si3N4 layer and has a thickness of 6 nm.

[0097] The optical indexes of the head-up display glasses of Examples 1 to 7 and Comparative Examples 1 to 4 were measured. The visible light transmittance of the head-up display glasses was measured, and the P-polarized light reflectance and visible light reflection color of the head-up display glasses were measured from the reflective coating side. The results of Examples 1 to 3 and Comparative Examples 1 to 4 are shown in Table 1, and the results of Examples 4 to 7 are shown in Table 2.

[0098] [Table 1]

[0099] Glass for head-up displays is usually required to simultaneously satisfy the following requirements: visible light reflectance is less than 15%, reflectance for P-polarized light incident at an incident angle of 60° is 15% or more, and reflectance for P-polarized light incident at an incident angle of 65° is 20% or more. Comparing Comparative Example 1 and Comparative Example 2 with Table 1, the reflective coatings of Comparative Example 1 and Comparative Example 2 have a laminated structure (TiO xIn the comparative example, only a high-refractive-index layer (SiO2) and a low-refractive-index layer (SiO2) were used, and the requirements for P-polarized light reflectance and visible light reflectance of the head-up display glass could not be simultaneously met by simply adjusting the thicknesses of the high-refractive-index layer and the low-refractive-index layer. For example, the head-up display glass of Comparative Example 1 met the requirement for a reflectance of less than 15% for visible light, but did not meet the requirement for a reflectance of less than 15% for P-polarized light incident at angles of incidence of 60° and 65°. The head-up display glass of Comparative Example 2 met the requirement for a reflectance of less than 15% for P-polarized light incident at angles of incidence of 60° and 65°, but did not meet the requirement for a reflectance of less than 15% for visible light. This indicates that while the P-polarized light reflectance can be increased to a certain extent by simply adjusting the thicknesses of the high-refractive-index layer and the low-refractive-index layer, the visible light reflectance also increases accordingly as the P-polarized light reflectance improves, even reaching 15% or more, thereby failing to meet the requirements. Therefore, it was found that the requirements for a relatively high reflectance for P-polarized light and a relatively low reflectance for visible light of the head-up display glass cannot be simultaneously met by simply providing a laminated structure.

[0100] In contrast, according to the data of Examples 1 to 3, the examples of the present application show that by providing an inner barrier layer and an improvement layer in the reflective coating, the reflectance of the head-up display glass for P-polarized light incident at an angle of 60° to 73° is increased to 17% to 35%. or increase to 16.1% to 33.8%, or increase to 17.3% to 35.1%, or increase to 18.5% to 35.6%, and even further increase the reflectance of the head-up display glass to visible light, while still maintaining it below 15%; The reflected color of the head-up display glass measured from the reflective coating has an a value of -4.2 to -1.8 and a b value of -7.2 to -5.2; In addition, the head-up display glass can have a neutral color. Furthermore, comparing Example 3 with Example 2, it can be seen that when no external barrier layer is used, the thermal stability of the entire reflective coating is slightly reduced, but the formed head-up display glass can still simultaneously meet the requirements for reflectance for P-polarized light and visible light.

[0101] Comparing Comparative Example 3 with Examples 1 and 2, the reflective coating of Comparative Example 3 does not have an internal barrier layer, and the improvement layer (NiCr / 1.5 nm) is in direct contact with the inner glass plate. During high-temperature heat treatment, the diffusion of metal ions and oxygen ions on the surface of the inner glass plate causes destruction and oxidation of the improvement layer, resulting in a decrease in the reflective ability of the head-up display glass for P-polarized light.

[0102] Comparing Comparative Example 4 with Examples 1 and 2, the reflective coating of Comparative Example 4 has an improved layer, but the improved layer has a laminated structure (TiO x The improvement layer is provided between the low refractive index layer (SiO2) and the outer barrier layer (Si3N4). and the outer barrier layer After P-polarized light and visible light are incident on the reflective coating from inside the vehicle, they are first absorbed and reflected by the improvement layer before passing through the high refractive index layer and the low refractive index layer, which reduces the performance of the entire reflective coating, resulting in a visible light transmittance of less than 70% for the head-up display glass and a P-polarized light reflectance of less than 15% or less than 20%, neither of which meets the requirements.

[0103] [Table 2]

[0104] According to the data of Examples 4 to 7, the reflectivity of the glass for head-up displays for P-polarized light incident at an angle of 60° to 73° is 15.2% to 32.4%, or 18.5% to 35.6%, or 19.5% to 37.5%, or 20.1% to 38.8%, and the reflected color of the glass for head-up displays measured from the reflective coating has an a value of -6.2 to -1.7 and a b value of -5.4 to -4.2.

[0105] As can be seen from Tables 1 and 2, the head-up display glasses according to Examples 1 to 7 of the present application have an increased reflectance of 17% to 35% for P-polarized light incident at an angle of 60° to 73°. or increased from 15.2% to 38.8%; It may even increase further, but the visible light reflectance remains below 15%. The reflected color of the head-up display glass measured from the reflective coating has an a value of -6.2 to -1.7 and a b value of -7.2 to -4.2;Furthermore, a neutral color can be obtained, which meets the requirements for automotive glass. Comparing Examples 6 and 7, when a material with a crystalline structure such as nanocrystalline silicon is used as the improvement layer, it can be seen that due to the reflective and transmissive properties of crystalline silicon for P-polarized light, the reflective coating formed using crystalline silicon as the improvement layer can improve P-polarized light reflectance to a certain extent compared to amorphous silicon, while maintaining a relatively high visible light transmittance and a relatively low visible light reflectance.

[0106] The above content is merely a preferred embodiment of the present application and is not used to limit the scope of the claims of the present application. Those skilled in the art can understand and realize the whole or part of the operation of the above embodiment, and equivalent changes made by those skilled in the art based on the claims of the present application still belong to the scope of coverage of the present application.

Claims

1. A glass for a head-up display, a laminated glass and a reflective coating capable of reflecting P-polarized light, the laminated glass includes an outer glass sheet, a polymer interlayer, and an inner glass sheet, the polymer interlayer being sandwiched between the outer glass sheet and the inner glass sheet; the reflective coating comprises a laminated internal barrier layer, an improvement layer, and at least one laminated structure, the internal barrier layer being provided on a surface of the inner glass sheet away from the polymer interlayer, the laminated structure comprising a high refractive index layer and a low refractive index layer laminated in sequence along a direction away from the internal barrier layer, the refractive index of the high refractive index layer being 1.8 or more, and the refractive index of the low refractive index layer being less than 1.7; the improvement layer is provided between the internal barrier layer and the laminated structure, or the improvement layer is provided between the high refractive index layer and the low refractive index layer; Glass for a head-up display.

2. the reflectance of the head-up display glass for P-polarized light incident at an incident angle θ is Y, θ satisfies 60°≦θ≦75°, and Y satisfies Y≧15%; 2. The glass for a head-up display according to claim 1.

3. When θ satisfies 65°≦θ≦75°, Y satisfies Y≧20%, and when θ satisfies 70°≦θ≦75°, Y satisfies Y≧27%.

3. The head-up display glass according to claim 2.

4. The reflectivity of the glass for the head-up display for visible light is less than 15%.

2. The glass for a head-up display according to claim 1.

5. The material of the inner barrier layer comprises at least one of oxides of Zn, Sn, Ti, Si, Al, Nb, Zr, Ni, Mg, Cr, Ta elements and oxides of alloys thereof, or at least one of nitrides of Si, Al, Zr, B, Ti elements and nitrides of alloys thereof, and / or The thickness of the inner barrier layer is 3 nm or more.

2. The glass for a head-up display according to claim 1.

6. The reflectance of the glass for a head-up display for P-polarized light incident at an angle of 60° to 73° is 15.2% to 38.8%.

2. The glass for a head-up display according to claim 1.

7. The material of the improved layer includes at least one of Ni, Cr, Fe, Ti, Mo, Cu, Al, Au, Sn, Zr, In, Si, Nb, Ge, W, Ta, Pd, and Pt elements, and alloys thereof.

2. The glass for a head-up display according to claim 1.

8. The element or alloy in the improved layer has a crystalline structure, and the thickness of the improved layer is 1 nm to 40 nm.

8. The glass for a head-up display according to claim 7.

9. The element or alloy in the improved layer has an amorphous structure, and the thickness of the improved layer is 1 nm to 5 nm.

8. The glass for a head-up display according to claim 7.

10. the reflective coating further comprises an outer barrier layer, the outer barrier layer being provided on a surface of the at least one laminate structure remote from the inner barrier layer; 2. The glass for a head-up display according to claim 1.

11. The material of the outer barrier layer includes at least one of nitrides of Si, Al, Zr, Ti, B, and Ni elements and nitrogen oxides of alloys thereof.

11. The glass for a head-up display according to claim 10.

12. The thickness of the outer barrier layer is 3 nm to 30 nm.

11. The glass for a head-up display according to claim 10.

13. the difference between the refractive index of the inner glass sheet and the refractive index of the polymer interlayer is 0.1 or less, and the difference between the refractive index of the outer glass sheet and the refractive index of the polymer interlayer is 0.1 or less; 2. The glass for a head-up display according to claim 1.

14. The reflected color of the head-up display glass measured from the reflective coating has an a value of -6.2 to -1.7 and a b value of -7.2 to -4.

2.

2. The glass for a head-up display according to claim 1.

15. A head-up display system, a projection light source for generating P-polarized light and the glass for a head-up display according to any one of claims 1 to 14, wherein the P-polarized light is projected onto the reflective coating; A head-up display system.

Citation Information

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