Head-up display glass and head-up display system

Abstract

Head-up display glass (200) and a head-up display system. The head-up display glass (200) comprises an outer glass plate (11), a thermoplastic intermediate layer (13) and an inner glass plate (12) which are stacked, and further comprises a transparent conductive layer (14), the transparent conductive layer (14) comprises a first metal layer (142), a second metal layer (144), a third metal layer (146) and a fourth metal layer (148) which are sequentially stacked, and the thickness meets: 0.7≤Ea4 / Ea1≤1.2; the head-up display glass (200) has reflectivity of at least 15% for projection light (101) incident from one side of a fourth surface (122) at an incident angle of 65°, and the projection light (101) comprises 40% to 80% S-polarized light and 20% to 60% P-polarized light.

Description

Head-up display glass and head-up display system

[0001] Related applications

[0002] This application claims priority to Chinese patent application number 202310704072.3, filed on June 14, 2023, entitled “Head-up display glass and head-up display system,” the entire text of which is hereby incorporated by reference. Technical Field

[0003] The present application relates to the field of head-up display technology, and in particular to head-up display glass and a head-up display system. Background Art

[0004] With the development of intelligent vehicles, higher requirements are being placed on the integrated functionality of automotive glass. Research on head-up displays (HUDs) has become a future development trend for many automakers. Currently, HUD systems typically consist of a projection device and HUD glass. The HUD glass, which serves as the vehicle's front windshield, has an inner surface facing the interior and an outer surface facing the exterior. The projection device projects image information onto the inner surface of the HUD glass, which then reflects it into the driver's eyes. However, conventional projection devices primarily produce S-polarized light, which is reflected from the inner surface of the glass, from air, and from the outer surface of the glass, from glass to air. This produces two offset images, known as double images, resulting in unclear HUD images and poor visual comfort.

[0005] At the same time, the vehicle's front windshield also needs to have heat insulation and even electric heating functions. A transparent conductive layer can be added to the head-up display glass. The transparent conductive layer can have multiple metal layers and dielectric layers. Since the transparent conductive layer will also reflect the projected light, a third offset image will be formed, the so-called triple image phenomenon, which makes the HUD image more blurred, thereby interfering with the driver's line of sight, which is not conducive to safe driving and makes the driver's visual comfort worse.

[0006] Existing projection devices on the market mostly use TFT screens, which primarily project S-polarized light. This doesn't meet the needs of drivers wearing sunglasses, as sunglasses typically only allow P-polarized light to pass through while blocking S-polarized light. In recent years, automotive OEMs have actively explored P-polarized or non-linearly polarized light imaging to meet the needs of customers wearing sunglasses and address market developments. For non-linearly polarized light imaging, since the projection light contains both S- and P-polarized light, completely eliminating the triple image phenomenon is difficult if a transparent conductive layer is included in the head-up display glass.

[0007] Summary of the Invention

[0008] Based on this, according to various embodiments of the present application, a head-up display glass and a head-up display system are provided, and the technical solution is as follows:

[0009] A head-up display glass comprises a laminated outer glass panel, a thermoplastic interlayer, and an inner glass panel, wherein the outer glass panel has a first surface and a second surface, the inner glass panel has a third surface and a fourth surface, and the thermoplastic interlayer is located between the second surface and the third surface.

[0010] The head-up display glass further includes a transparent conductive layer, which is located on the second surface, or on the third surface, or in the thermoplastic intermediate layer; the thermoplastic intermediate layer has a wedge-shaped profile; the transparent conductive layer includes a first metal layer, a second metal layer, a third metal layer, and a fourth metal layer stacked in sequence;

[0011] The physical thickness of the first metal layer is Ea1 and the physical thickness of the fourth metal layer is Ea4, and Ea1 and Ea4 satisfy: 0.7≤Ea4 / Ea1≤1.2;

[0012] The head-up display glass has a reflectivity of at least 15% for projection light incident from the fourth surface at an incident angle of 65°, and the projection light contains 40% to 80% of S-polarized light and 20% to 60% of P-polarized light.

[0013] A head-up display system includes a projection device and the head-up display glass described above. The projection device is used to generate projection light, wherein the projection light contains 40% to 80% S-polarized light and 20% to 60% P-polarized light. The projection light is incident on the fourth surface of the head-up display glass at an incident angle of 38° to 85°.

[0014] In some embodiments, the head-up display system further includes at least one sensor, which is mounted on the fourth surface. The detection signal emitted and / or received by the sensor passes through the head-up display glass. The area of ​​the head-up display glass through which the detection signal passes is a signal transmission window, and the transparent conductive layer is not provided in the signal transmission window.

[0015] The details of one or more embodiments of the present application are set forth in the description below, and other features, objects, and advantages of the application will become apparent from the description and from the claims thereof. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the conventional technology, the following briefly introduces the drawings required for use in the embodiments or the conventional technology descriptions. Obviously, the drawings described below are merely embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the disclosed drawings without any creative work.

[0017] FIG1 is a schematic structural diagram of a head-up display system provided by one embodiment of the present application;

[0018] FIG2 is a schematic cross-sectional view of a head-up display glass according to another embodiment of the present application;

[0019] FIG3 is a schematic diagram of the cross-sectional structure of a transparent conductive layer provided in one embodiment of the present application. DETAILED DESCRIPTION

[0020] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0021] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application pertains. The terms used herein in the specification of this application are for the purpose of describing specific embodiments only and are not intended to limit this application.

[0022] the term

[0023] Unless otherwise specified or incompatible herewith, the terms and phrases used herein shall have the following meanings:

[0024] In this application, "a plurality of" means at least two, such as two, three, etc., unless otherwise clearly defined. "Several" means at least one, such as one, two, etc., unless otherwise clearly defined.

[0025] In this application, when a numerical range is involved, unless otherwise specified, both endpoints of the numerical range are included.

[0026] In this application, "layer" can be understood as a single layer or a plurality of overlapping layers.

[0027] In the present application, the incident angle is the angle between the projection light generated by the projection device and the normal line of one surface of the head-up display glass when the projection light is incident on the surface.

[0028] In the present application, the refractive index is the refractive index of transmitted light at a wavelength of 550 nm.

[0029] Referring to FIG. 1 , a head-up display system provided in one embodiment of the present application includes a projection device 100 and head-up display glass 200. The projection device 100 is used to generate projection light 101. The head-up display glass 200 includes a laminated outer glass plate 11, a thermoplastic interlayer 13, an inner glass plate 12, and a transparent conductive layer 14. The outer glass plate 11 has a first surface 111 and a second surface 112, and the inner glass plate 12 has a third surface 121 and a fourth surface 122. The thermoplastic interlayer 13 is located between the second surface 112 and the third surface 121. The transparent conductive layer 14 comprises multiple metal layers and has high visible light transmittance, high infrared reflectivity, and good electrical conductivity. This enables the head-up display glass to not only achieve head-up display functionality but also possess excellent thermal insulation and even electrical heating properties.

[0030] In this embodiment, the projection light 101 includes 40% to 80% S-polarized light and 20% to 60% P-polarized light. The projection light 101 is incident on the fourth surface 122 of the head-up display glass 200 at an incident angle of 38° to 85°. The projection light 101 is reflected by the head-up display glass 200 and enters the human eye 300, thereby allowing the human eye to observe a head-up display (HUD) image 400 located in front of the head-up display glass 200. Specifically, the projection light 101 contains 40% S-polarized light and 60% P-polarized light, 50% S-polarized light and 50% P-polarized light, 60% S-polarized light and 40% P-polarized light, 70% S-polarized light and 30% P-polarized light, 80% S-polarized light and 20% P-polarized light. Preferably, the projection light 101 contains 50% to 70% S-polarized light and 30% to 50% P-polarized light, which can meet the higher brightness requirements of the head-up display image and the need of the driver wearing sunglasses.

[0031] As can be understood, the outer glass sheet 11, the inner glass sheet 12, the thermoplastic interlayer 13, and the transparent conductive layer 14 are stacked along the thickness direction of the head-up display glass 200. The first surface 111 of the outer glass sheet 11 faces the vehicle exterior and is further from the thermoplastic interlayer 13 than the second surface 112. The fourth surface 122 of the inner glass sheet 12 faces the vehicle interior and is further from the thermoplastic interlayer 13 than the third surface 121. The thermoplastic interlayer 13 is sandwiched between the second surface 112 and the third surface 121 to bond the outer glass sheet 11 and the inner glass sheet 12 together to form a laminated glass structure. The thermoplastic interlayer 13 can be made of polyvinyl butyral (PVB), ethylene vinyl acetate (EVA), or ionotropic polymer film (SGP). The thermoplastic interlayer 13 may be a single-layer structure or a multi-layer structure, such as a two-layer structure, a three-layer structure, a four-layer structure, or even a five-layer structure. For example, if the thermoplastic interlayer 13 is a three-layer PVB, one of the PVB layers has a higher plasticizer content, thereby providing the head-up display glass 200 with a sound insulation function, and at least one of the PVB layers has a wedge-shaped profile, thereby partially eliminating ghosting.

[0032] The transparent conductive layer 14 is located on the second surface 112 , or on the third surface 121 , or in the thermoplastic intermediate layer 13 . In this embodiment, as shown in FIG1 , the transparent conductive layer 14 is directly disposed on the second surface 112 ; in another embodiment, as shown in FIG2 , the transparent conductive layer 14 is directly disposed on the third surface 121 ; in yet another embodiment, the transparent conductive layer 14 is directly disposed on a thermoplastic film. The material of the thermoplastic film can be polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyimide (PI), cellulose triacetate (TAC), etc. The thermoplastic film provided with the transparent conductive layer 14 is sandwiched between the second surface 112 and the third surface 121 , specifically, between the second surface 112 and the thermoplastic intermediate layer 13 , between the thermoplastic intermediate layer 13 and the third surface 121 , or within the thermoplastic intermediate layer 13 . For example, the thermoplastic intermediate layer 13 includes two layers of transparent PVB, and the thermoplastic film provided with the transparent conductive layer 14 is sandwiched between the two layers of transparent PVB. The transparent conductive layer 14 may be deposited on the second surface 112 , the third surface 121 or the thermoplastic film by a magnetron sputtering process.

[0033] The head-up display glass 200 of this embodiment has no special requirements for the projection light 101 emitted by the projection device 100. It can break free from the limitations of traditional TFT screen projection and eliminates the need for linear polarization design for ordinary screen projection, making it compatible with a wider range of screen projections, such as OLED and LCD screens. Specifically, the projection light 101 described in this application is a mixed polarization light containing both S-polarized and P-polarized light, such as natural light, partially polarized light, circularly polarized light, or elliptically polarized light. This meets the high brightness requirements of the head-up display image while also allowing the driver to wear sunglasses.

[0034] As can be understood, during the process of forming the head-up display (HUD) image 400, the projection light 101 is reflected off the fourth surface 122, the transparent conductive layer 14, and the first surface 111. The image formed by the reflection on the fourth surface 122 serves as the HUD primary image, the image formed by the reflection on the first surface 111 serves as the first ghost image, and the image formed by the reflection on the transparent conductive layer 14 serves as the second ghost image. To directly eliminate the first ghost image, the thermoplastic interlayer 13 employed in this embodiment has a wedge-shaped profile. Compared to conventional thermoplastic interlayers of uniform thickness, the wedge-shaped thermoplastic interlayer 13 enables the first ghost image to overlap with the HUD primary image, thereby eliminating visual ghosting. In this embodiment, when the head-up display glass 200 is installed on a vehicle as a front windshield, the thermoplastic interlayer 13 exhibits a wedge-shaped profile with a greater thickness at the top than at the bottom. Preferably, the wedge-shaped profile has at least one wedge angle, which is between 0.05 mrad and 0.6 mrad. Specifically, the wedge profile may have a constant wedge angle, such as 0.05 mrad, 0.1 mrad, 0.15 mrad, 0.2 mrad, 0.25 mrad, 0.3 mrad, 0.35 mrad, 0.4 mrad, 0.45 mrad, 0.5 mrad, 0.55 mrad, 0.6 mrad, etc. The wedge profile may also have multiple constant wedge angles, such as two constant wedge angles, three constant wedge angles, or even more constant wedge angles. The two constant wedge angles may be a first wedge angle of 0.38 mrad for achieving a HUD image and a second wedge angle of 0.10 mrad for achieving no perspective ghosting of the camera window. The three constant wedge angles may be a first wedge angle of 0.5 mrad for achieving a first HUD image, a first wedge angle of 0.4 mrad for achieving a second HUD image, a third wedge angle of 0.2 mrad for achieving a third HUD image, etc. In the section with the constant wedge angles, the thickness of the wedge profile varies linearly. It is understandable that the wedge-shaped profile may also have a continuously variable wedge angle, which causes the thickness of the wedge-shaped profile to change nonlinearly. The continuously variable wedge angle may obtain a head-up display image with a larger field of view (FOV) and a larger image size without visual ghosting.

[0035] In this embodiment, as shown in Figure 3, the transparent conductive layer 14 includes a first dielectric layer 141, a first metal layer 142, a second dielectric layer 143, a second metal layer 144, a third dielectric layer 145, a third metal layer 146, a fourth dielectric layer 147, a fourth metal layer 148, and a fifth dielectric layer 149 stacked in sequence along the thickness direction of the head-up display glass 200. In this embodiment, when the transparent conductive layer 14 can be deposited on the second surface 112 by a magnetron sputtering process, the first dielectric layer 141 is directly deposited on the second surface 112, and the first metal layer 142, the second dielectric layer 143, the second metal layer 144, the third dielectric layer 145, the third metal layer 146, the fourth dielectric layer 147, the fourth metal layer 148 and the fifth dielectric layer 149 are sequentially away from the second surface 112; in another embodiment, when the transparent conductive layer 14 can be deposited on the third surface 121 by a magnetron sputtering process, the first dielectric layer 141 is directly deposited on the third surface 121, and the first metal layer 14 2. The second dielectric layer 143, the second metal layer 144, the third dielectric layer 145, the third metal layer 146, the fourth dielectric layer 147, the fourth metal layer 148 and the fifth dielectric layer 149 are sequentially away from the third surface 121; in another embodiment, when the transparent conductive layer 14 is deposited on the thermoplastic film by a magnetron sputtering process, the first dielectric layer 141 is directly deposited on the thermoplastic film, and the first metal layer 142, the second dielectric layer 143, the second metal layer 144, the third dielectric layer 145, the third metal layer 146, the fourth dielectric layer 147, the fourth metal layer 148 and the fifth dielectric layer 149 are sequentially away from the thermoplastic film. For the second ghost image formed by the reflection of the transparent conductive layer 14, the present application designs a film system for the transparent conductive layer 14 so that the transparent conductive layer 14 has a low reflectivity for the projection light 101 with a wavelength of 400nm to 700nm and 600nm to 700nm, so as to achieve an image brightness ratio C(400-700)≤0.15 for the projection light 101 with a wavelength of 400nm to 700nm incident from the side of the fourth surface at an incident angle of 65°, and an image brightness ratio C(600-700)≤0.3 for the projection light 101 with a wavelength of 600nm to 700nm incident from the side of the fourth surface at an incident angle of 65°, while ensuring that the head-up display glass 200 On the basis of having the functions of heat insulation and electric heating, it can greatly reduce the brightness and recognition of the ghosting formed by the reflection of the transparent conductive layer 14, which is conducive to achieving the effect of visually no ghosting, thereby improving thermal comfort, visual comfort and driving safety.At the same time, in order to achieve a better head-up display effect, the head-up display glass 200 has a reflectivity of at least 15% for the projection light 101 incident from the side of the fourth surface at an incident angle of 65°, for example, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, etc.

[0036] The materials of the first metal layer 142 , the second metal layer 144 , the third metal layer 146 and the fourth metal layer 148 are independently selected from one or more of silver and silver alloys, and the silver alloy is preferably an alloy of silver and at least one of gold, aluminum, copper, indium and platinum.

[0037] The physical thickness of the first metal layer 142 is Ea1 and the physical thickness of the fourth metal layer 148 is Ea4. The Ea1 and Ea4 satisfy the following relationship: 0.7≤Ea4 / Ea1≤1.2. It is understood that Ea4 / Ea1 can be 0.7, 0.75, 0.8, 0.85, 0.9, 0.95, 1, 1.05, 1.1, 1.15, 1.2, etc. Preferably, 0.75≤Ea4 / Ea1≤1.15, 0.80≤Ea4 / Ea1≤1.1, or 0.80≤Ea4 / Ea1≤1.05. More preferably, or 0.80≤Ea4 / Ea1≤1. Further preferably, 0.80≤Ea4 / Ea1≤0.95.

[0038] The physical thickness of the second metal layer 144 is Ea2 and the physical thickness of the third metal layer 146 is Ea3. The Ea1, Ea2, Ea3 and Ea4 satisfy at least one of the following conditions:

[0039] (1)0.60≤Ea4 / Ea2≤0.80;

[0040] It can be understood that Ea4 / Ea2 can be 0.60, 0.65, 0.70, 0.75, 0.80, etc.

[0041] (2)0.60≤Ea4 / Ea3≤0.80;

[0042] It can be understood that Ea4 / Ea3 can be 0.60, 0.65, 0.70, 0.75, 0.80, etc.

[0043] (3) Ea1+Ea2+Ea3+Ea4≥40nm;

[0044] It can be understood that the sum of the physical thicknesses of the four metal layers Ea1+Ea2+Ea3+Ea4 can be 40 nm, 41 nm, 42 nm, 43 nm, 44 nm, 45 nm, 46 nm, 47 nm, 48 nm, 49 nm, 50 nm, 51 nm, 52 nm, 53 nm, 54 nm, 55 nm, 56 nm, etc. Preferably, 45 nm ≤ Ea1+Ea2+Ea3+Ea4 ≤ 55 nm.

[0045] (4) At least one of Ea1, Ea2, Ea3, and Ea4 is less than or equal to 11 nm;

[0046] It can be understood that only one of Ea1, Ea2, Ea3 and Ea4 may be less than or equal to 11nm, for example, Ea4≤11nm; only two of Ea1, Ea2, Ea3 and Ea4 may be less than or equal to 11nm, for example, Ea1≤11nm and Ea4≤11nm.

[0047] (5) The difference between the maximum and minimum values ​​of Ea1, Ea2, Ea3, and Ea4 is less than or equal to 5 nm;

[0048] It can be understood that the difference between the maximum value and the minimum value of Ea1, Ea2, Ea3 and Ea4 can be 3nm, 3.5nm, 4nm, 4.5nm, 5nm, etc.

[0049] Among them, the first dielectric layer 141 is located on the side of the first metal layer 142 away from the second metal layer 144, the second dielectric layer 143 is located between the first metal layer 142 and the second metal layer 144, the third dielectric layer 145 is located between the second metal layer 144 and the third metal layer 146, the fourth dielectric layer 147 is located between the third metal layer 146 and the fourth metal layer 148, and the fifth dielectric layer 149 is located on the side of the fourth metal layer 148 away from the third metal layer 146. The materials of the first dielectric layer 141, the second dielectric layer 143, the third dielectric layer 145, the fourth dielectric layer 147 and the fifth dielectric layer 149 are each independently selected from oxides of Zn, Mg, Sn, Ti, Nb, Zr, Ni, In, Al, Ce, W, Mo, Sb, Bi, or nitrides, nitride oxides and mixtures thereof of Si, Al, Zr, Y, Ce, La, such as zinc stannate, magnesium-doped zinc stannate, zinc oxide, magnesium-doped zinc oxide, zirconium-doped zinc oxide, niobium oxide, bismuth oxide, aluminum-doped zinc oxide, zirconium oxide, titanium oxide, titanium peroxide, etc. Optionally, the first dielectric layer 141, the second dielectric layer 143, the third dielectric layer 145, the fourth dielectric layer 147, and the fifth dielectric layer 149 each independently include at least two dielectric sub-layers. For example, FIG3 shows that the first dielectric layer 141 includes two dielectric sub-layers, the second dielectric layer 143, the third dielectric layer 145, and the fourth dielectric layer 147 each include four dielectric sub-layers, and the fifth dielectric layer 149 includes three dielectric sub-layers. It will be understood that when each dielectric layer has a single-layer structure, its total physical thickness is the physical thickness of the layer; when each dielectric layer has a multi-layer structure, its total physical thickness is the sum of the physical thicknesses of all dielectric sub-layers in the layer.

[0050] The total physical thickness of the first dielectric layer is Eo1, the total physical thickness of the second dielectric layer is Eo2, the total physical thickness of the third dielectric layer is Eo3, the total physical thickness of the fourth dielectric layer is Eo4, and the total physical thickness of the fifth dielectric layer is Eo5; Eo1, Eo2, Eo3, Eo4, and Eo5 satisfy at least one of the following conditions:

[0051] (1)0.40 <Eo1 / Eo2<0.90;

[0052] It is understood that Eo1 / Eo2 may be 0.41, 0.45, 0.50, 0.55, 0.60, 0.65, 0.70, 0.75, 0.80, 0.85, 0.89, etc. Preferably, 0.45 ≤ Eo1 / Eo2 ≤ 0.80. More preferably, 0.45 ≤ Eo1 / Eo2 ≤ 0.70. Even more preferably, 0.45 ≤ Eo1 / Eo2 ≤ 0.60.

[0053] (2)0.40 <Eo1 / Eo3<0.90;

[0054] It is understood that Eo1 / Eo3 may be 0.41, 0.45, 0.50, 0.55, 0.60, 0.65, 0.70, 0.75, 0.80, 0.85, 0.89, etc. Preferably, 0.45 ≤ Eo1 / Eo3 ≤ 0.80. More preferably, 0.50 ≤ Eo1 / Eo3 ≤ 0.75. Even more preferably, 0.50 ≤ Eo1 / Eo3 ≤ 0.65.

[0055] (3)0.35 <Eo1 / Eo4<0.90;

[0056] It is understood that Eo1 / Eo4 can be 0.36, 0.40, 0.45, 0.50, 0.55, 0.60, 0.65, 0.70, 0.75, 0.80, 0.85, 0.89, etc. Preferably, 0.40 ≤ Eo1 / Eo4 ≤ 0.80. More preferably, 0.45 ≤ Eo1 / Eo4 ≤ 0.70. Even more preferably, 0.50 ≤ Eo1 / Eo4 ≤ 0.60.

[0057] (4)0.50 <Eo1 / Eo5<1.50;

[0058] It is understood that Eo1 / Eo5 can be 0.51, 0.55, 0.60, 0.65, 0.70, 0.75, 0.80, 0.85, 0.90, 1.00, 1.05, 1.10, 1.15, 1.20, 1.25, 1.30, 1.35, 1.40, 1.45, 1.49, etc. Preferably, 0.55 ≤ Eo1 / Eo5 ≤ 1.45. More preferably, 0.70 ≤ Eo1 / Eo5 ≤ 1.40. Even more preferably, 0.90 ≤ Eo1 / Eo5 ≤ 1.35.

[0059] In some embodiments, at least one of the first dielectric layer 141, the second dielectric layer 143, the third dielectric layer 145, the fourth dielectric layer 147, and the fifth dielectric layer 149 comprises at least two dielectric sublayers, and the refractive index of at least one dielectric sublayer is greater than or equal to 2.0. Preferably, the material of the at least one dielectric sublayer is TiOx or NbOx, and the refractive index of the TiOx layer and the NbOx layer is greater than or equal to 2.3.

[0060] In some embodiments, at least one dielectric sub-layer included in at least one of the second dielectric layer 143, the third dielectric layer 145, and the fourth dielectric layer 147 is a visible light absorbing layer, and the material of the visible light absorbing layer is selected from at least one of NiCr, NiCrOx, Ti, ZnSn, and Sn. Preferably, the physical thickness of the visible light absorbing layer is Eo6, and Eo6 and Eo1, Eo2, Eo3, Eo4, and Eo5 satisfy the following relationship: Eo6 / (Eo1+Eo2+Eo3+Eo4+Eo5)=0.001-0.005, and specifically can be 0.001, 0.0015, 0.002, 0.0025, 0.003, 0.0035, 0.004, 0.0045, 0.005, etc.

[0061] Among them, the multiple metal layers and the multiple dielectric layers can be deposited layer by layer through a magnetron sputtering process. By optimizing the materials and thicknesses of the metal layers and the dielectric layers, the transparent conductive layer 14 can withstand subsequent high-temperature heat treatment and other bending forming processes, and the optical properties and mechanical properties of the obtained head-up display glass 200 can meet the use standards of vehicle glass.

[0062] In some embodiments, the visible light reflectivity of the head-up display glass 200 measured from the side of the fourth surface is less than 10%, and can be specifically 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, etc., to prevent the dashboard in the vehicle from forming a clear reflection on the head-up display glass 200, which will seriously affect driving safety and visual comfort.

[0063] In some embodiments, the visible light transmittance of the head-up display glass 200 is greater than or equal to 70%, specifically 70%, 71%, 72%, 73%, 74%, 75%, 80%, 85%, etc., to meet the safety use standards of vehicle glass.

[0064] In some embodiments, the 8° reflection color and 65° reflection color of the head-up display glass 200 are measured from the first surface side, and the a value in the Lab value of the 8° reflection color is less than 0, and the a value in the Lab value of the 65° reflection color is less than 0, so that the head-up display glass 200 has an excellent appearance color.

[0065] In some embodiments, the sheet resistance of the transparent conductive layer 14 is less than or equal to 0.7Ω / □, and can specifically be 0.4Ω / □, 0.45Ω / □, 0.5Ω / □, 0.55Ω / □, 0.6Ω / □, 0.65Ω / □, 0.7Ω / □, etc., so that the head-up display glass 200 has excellent thermal insulation performance. Preferably, the total solar energy transmittance of the head-up display glass 200 is less than or equal to 45%, and can specifically be 38%, 39%, 40%, 41%, 42%, 43%, 44%, 45%, etc.

[0066] In some embodiments, the transparent conductive layer 14 can also provide the head-up display glass 200 with excellent electrical heating performance, thereby enabling rapid defrosting, defogging, de-icing, and snow removal. To achieve this electrical heating performance, the head-up display glass 200 also includes a first busbar and a second busbar that are in direct electrical contact with the transparent conductive layer 14. A power supply inputs current into the transparent conductive layer through the first and second busbars. The power supply can provide a supply voltage of 12V to 60V.

[0067] In some embodiments, the head-up display system further includes at least one sensor mounted on the fourth surface 122. The detection signals transmitted and / or received by the sensor pass through the head-up display glass 200. The area of ​​the head-up display glass 200 through which the detection signals pass serves as a signal transmission window. The transparent conductive layer 14 is not disposed within the signal transmission window, thereby preventing interference or blocking of the detection signals by the transparent conductive layer 14. This omission of the transparent conductive layer 14 within the signal transmission window can be achieved through a film removal process. The film removal process can employ pre-coating masking, post-coating laser removal, friction removal, chemical etching, and the like. The sensor can be a visible light camera, a thermal imager, a lidar, a millimeter-wave radar, and the like.

[0068] In the present application, the projection device 100 projects using three RGB (red, green, blue) light paths, and the wavelength of the projection light 101 is 380nm to 780nm, thereby realizing image display of any color. To significantly reduce the brightness of ghosting caused by reflection from the transparent conductive layer 14 and facilitate achieving a visually non-ghosting effect, the head-up display glass 200 preferably has an image brightness ratio C(400-700) ≤ 0.17 for projection light 101 with a wavelength of 400 nm to 700 nm incident from the fourth surface at an incident angle of 65°. Specifically, the image brightness ratio C(400-700) may be 0.17, 0.16, 0.15, 0.14, 0.13, 0.12, 0.11, 0.10, 0.09, 0.08, 0.07, 0.06, 0.05, 0.04, 0.03, 0.02, 0.01, etc. The smaller the image brightness ratio C(400-700), the easier it is to achieve a visually non-ghosting effect. More preferably, C(400-700) ≤ 0.16. Even more preferably, C(400-700) ≤ 0.15. Among them, the image brightness ratio C(400~700) can be calculated using C(400~700)=Cf(400~700) / C4(400~700), C4(400~700) represents the brightness of the head-up display image after the first ghost image overlaps with the HUD main image, and Cf(400~700) represents the brightness of the second ghost image formed by reflection of the transparent conductive layer. C4(400~700) and Cf(400~700) can be obtained by measuring with a luminance meter based on light source A and a filter of 400nm~700nm.

[0069] In order to reduce the human eye's recognition of ghosting caused by reflection from the transparent conductive layer 14, it is preferred that the head-up display glass 200 has an image brightness ratio C(600-700) ≤ 0.45 for the projection light 101 with a wavelength of 600 nm to 700 nm incident from the fourth surface at an incident angle of 65°, and specifically can be 0.45, 0.44, 0.43, 0.42, 0.41, 0.4, 0.39, 0.38 , 0.37, 0.36, 0.35, 0.34, 0.33, 0.32, 0.31, 0.3, 0.29, 0.28, 0.27, 0.26, 0.25, 0.24, 0.23, 0.22, 0.21, 0.20, 0.19, 0.18, 0.17, 0.16, 0.15, etc. The smaller the image brightness ratio C(600-700), the easier it is to achieve a visually non-ghosting effect. More preferably, C(600-700) ≤ 0.4. Even more preferably, C(600-700) ≤ 0.35. Among them, the image brightness ratio C(600-700) can be calculated using C(600-700)=Cf(600-700) / C4(600-700), C4(600-700) represents the brightness of the head-up display image after the first ghost image overlaps with the HUD main image, and Cf(600-700) represents the brightness of the second ghost image formed by reflection of the transparent conductive layer. C4(600-700) and Cf(600-700) can be obtained by measuring with a luminance meter based on light source A and a 600nm-700nm filter.

[0070] In order to achieve the most color-neutral display of the HUD image, the reflectivity of the head-up display glass 200 to the projection light 101 with a wavelength of 469nm, 532nm, and 629nm incident from the side of the fourth surface at an incident angle of 65° is R4(469), R4(532), and R4(629). Preferably, the difference between the maximum value and the minimum value of R4(469), R4(532), and R4(629) is less than or equal to 4%, and can be specifically 4%, 3.5%, 3%, 2.5%, 2%, 1.5%, 1%, etc. The smaller the difference between the maximum value and the minimum value of R4(469), R4(532), and R4(629), the easier it is to obtain a smooth reflection spectrum, and the more color-neutral display can be achieved.

[0071] In summary, the head-up display glass and head-up display system of the embodiments of the present application, through the design of the transparent conductive layer, have a low reflectivity for projection light with wavelengths of 400nm to 700nm and 600nm to 700nm. Thus, while ensuring that the head-up display glass has heat insulation and electric heating functions, it can significantly reduce the brightness and recognizability of ghosting caused by reflection from the transparent conductive layer, which is conducive to achieving a visually ghost-free effect and improving thermal comfort, visual comfort and driving safety.

[0072] At the same time, this application has no special requirements for the projection light emitted by the projection device, can get rid of the limitations of traditional TFT screen projection, and does not require linear polarization design for ordinary screen projection. It can match more OLED, LCD and other screen projections, and meet the needs of people in the car wearing sunglasses.

[0073] Comparative Examples 1-2 and Examples 1-5

[0074] An outer glass panel 11, a thermoplastic interlayer 13, and an inner glass panel 12 were prepared. Both the outer glass panel 11 and the inner glass panel 12 were made of 2.1 mm thick transparent glass. The thermoplastic interlayer 13 was made of a transparent wedge-shaped PVB with an average thickness of 0.76 mm. A transparent conductive layer 14 according to Comparative Examples 1-2 and Examples 1-5 in Table 1 was deposited on the second surface 112 or the third surface 121 by magnetron sputtering. The glass was then processed and manufactured according to automotive glass production processes to obtain head-up display glass having the transparent conductive layer 14 according to Comparative Examples 1-2 and Examples 1-5.

[0075] Table 1: Transparent conductive layers of Comparative Examples 1-2 and Examples 1-5

[0076] According to the transparent conductive layers of Comparative Examples 1-2 and Examples 1-5 in Table 1, the physical thickness Ea1 of the first metal layer, the physical thickness Ea2 of the second metal layer, the physical thickness Ea3 of the third metal layer, and the physical thickness Ea4 of the fourth metal layer satisfy the film system design conditions, as well as the physical thickness Eo1 of the first dielectric layer, the physical thickness Eo2 of the second dielectric layer, the physical thickness Eo3 of the third dielectric layer, the physical thickness Eo4 of the fourth dielectric layer, and the physical thickness Eo5 of the fifth dielectric layer satisfy the film system design conditions, and the calculation results are included in Table 2.

[0077] Table 2: Film design conditions for the transparent conductive layer of Comparative Examples 1-2 and Examples 1-5

[0078] A head-up display system was constructed using a head-up display glass 200 having the transparent conductive layer 14 of Comparative Examples 1-2 and Examples 1-5 and a projection device 100. The projection device 100 generated projection light 101 consisting of 50% P-polarized light and 50% S-polarized light. The projection light was incident on the fourth surface 122 of the head-up display glass 200 at an angle of incidence between 38° and 85°. The position of the projection device 100 and the angle of incidence of the projection light 101 were adjusted to maximize the clarity of the head-up display image observed by the observer. The following optical properties were measured and calculated, and the results are reported in Table 3.

[0079] Visible light transmittance TL: According to ISO9050, the transmittance of the head-up display glass to visible light with a range of 380nm to 780nm incident at an incident angle of 8° is measured and calculated;

[0080] Visible light reflectance RL: The reflectance of the head-up display glass for visible light with a range of 380 nm to 780 nm incident at an incident angle of 8° is measured from the fourth surface according to ISO 9050.

[0081] Projection light reflectivity R65: The reflectivity of the head-up display glass for projection light with a wavelength of 380nm to 780nm incident at an incident angle of 65° is measured from the fourth surface according to ISO9050.

[0082] Reflected color a(8): measured from the first surface side at an incident angle of 8°, based on a D65 illuminant and a viewing angle of 10°, calculated according to the CIE Lab color model, where the a value represents the red-green value and the b value represents the yellow-blue value.

[0083] Reflected color a(65): measured from the first surface side at an incident angle of 65°, based on a D65 light source and a 10° viewing angle, calculated according to the CIE Lab color model, where the a value represents the red-green value, and the b value represents the yellow-blue value.

[0084] Image brightness ratio C(400-700): calculated using C(400-700)=Cf(400-700) / C4(400-700);

[0085] C4 (400-700): Based on light source A and a 400-700 nm filter, a luminance meter is used to measure the brightness of the head-up display image reflected from the head-up display glass.

[0086] Cf (400-700): Based on light source A and a 400nm-700nm filter, the brightness of the second ghost formed by the reflection of the transparent conductive layer is measured using a luminance meter;

[0087] Image brightness ratio C(600-700): calculated using C(600-700)=Cf(600-700) / C4(600-700);

[0088] C4 (600-700): Based on light source A and a 600nm-700nm filter, a luminance meter is used to measure the brightness of the head-up display image formed by the reflection of the head-up display glass;

[0089] Cf (600-700): Based on light source A and a 600nm-700nm filter, the brightness of the second ghost formed by the reflection of the transparent conductive layer is measured using a luminance meter;

[0090] R4(469), R4(532), R4(629): The reflectivity of the head-up display glass for projection light with a wavelength of 469 nm, 532 nm, and 629 nm incident at an incident angle of 65° is calculated from the fourth surface according to ISO9050;

[0091] Table 3: Optical performance measurement results of the head-up display glasses of Comparative Examples 1-2 and Examples 1-5

[0092] As can be seen from Tables 2 and 3, Comparative Example 1 uses a transparent conductive layer with Ea4 / Ea1>1.2, and the reflection color a(65) of the head-up display glass prepared is reddish, and the image brightness ratio C(400-700) is greater than 0.18. Therefore, it can be seen that Comparative Example 1 cannot achieve the visual effect of no ghosting and the head-up display glass does not have an excellent appearance color while making the head-up display glass have heat insulation and even electric heating functions.

[0093] Comparative Example 2 uses a transparent conductive layer with Ea4 / Ea1>1.2, Ea4 / Ea2>1.2, and Ea4 / Ea2>1.2. The reflection colors a(8) and a(65) of the prepared head-up display glass are both seriously reddish, the image brightness ratio C(400~700) is greater than 0.5, the image brightness ratio C(600~700) is greater than 1, the visible light reflectivity RL is greater than 10%, and the difference between the maximum and minimum values ​​of R4(469), R4(532), and R4(629) reaches 10%. It can be seen that Comparative Example 2, while making the head-up display glass have heat insulation and even electric heating functions, cannot achieve the effect of visually no ghosting, the head-up display glass does not have an excellent appearance color, and the head-up display image cannot achieve color neutral display, and even the instrument panel reflection is relatively serious.

[0094] In Example 1-5, by designing a film system for the transparent conductive layer, the head-up display glass obtained has a reflection color a(8) and a(65) both less than 0, a visible light reflectivity RL both less than 10%, a projection light reflectivity R65 both greater than 15%, an image brightness ratio C(400-700) both ≤ 0.15, an image brightness ratio C(600-700) both ≤ 0.3, and a difference between the maximum and minimum values ​​of R4(469), R4(532), and R4(629) both less than 4%; Among them, the difference between the maximum value and the minimum value of R4(469), R4(532), and R4(629) in Example 2 is less than 2%, and the image brightness ratios C(400-700)≤0.1 and C(600-700)≤0.2 in Example 3. It can be seen that Examples 1-5 can achieve the effect of visually no ghosting, the head-up display glass has excellent appearance color, and the head-up display image realizes color-neutral display on the basis of making the head-up display glass have heat insulation and even electric heating functions.

[0095] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0096] The above-described embodiments merely represent several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the spirit of the present application, and these modifications and improvements fall within the scope of protection of the present application. Therefore, the scope of protection of the present patent application shall be determined by the appended claims.

Claims

1. A head-up display glass, comprising a laminated outer glass plate, a thermoplastic interlayer and an inner glass plate, wherein the outer glass plate has a first surface and a second surface, the inner glass plate has a third surface and a fourth surface, and the thermoplastic interlayer is located between the second surface and the third surface; characterized in that: The head-up display glass further includes a transparent conductive layer, which is located on the second surface, on the third surface, or in the thermoplastic intermediate layer; the thermoplastic intermediate layer has a wedge-shaped profile; the transparent conductive layer includes a first metal layer, a second metal layer, a third metal layer, and a fourth metal layer stacked in sequence; The physical thickness of the first metal layer is Ea1 and the physical thickness of the fourth metal layer is Ea4, and Ea1 and Ea4 satisfy: 0.7≤Ea4 / Ea1≤1.2; The head-up display glass has a reflectivity of at least 15% for projection light incident from the fourth surface at an incident angle of 65°, and the projection light contains 40% to 80% of S-polarized light and 20% to 60% of P-polarized light.

2. The head-up display glass according to claim 1, characterized in that: The physical thickness of the second metal layer is Ea2 and the physical thickness of the third metal layer is Ea3, and Ea1, Ea2, Ea3 and Ea4 satisfy at least one of the following conditions: (1) 0.80≤Ea4 / Ea1≤1.1; (2) 0.60≤Ea4 / Ea2≤0.80; (3) 0.60≤Ea4 / Ea3≤0.80; (4) Ea1+Ea2+Ea3+Ea4≥40nm; (5) At least one of Ea1, Ea2, Ea3 and Ea4 is less than or equal to 11 nm; and (6) The difference between the maximum value and the minimum value among Ea1, Ea2, Ea3 and Ea4 is less than or equal to 5 nm.

3. The head-up display glass according to any one of claims 1 to 2, characterized in that: The materials of the first metal layer, the second metal layer, the third metal layer and the fourth metal layer are each independently selected from one or more of silver and silver alloys.

4. The head-up display glass according to any one of claims 1 to 3, characterized in that: The transparent conductive layer further comprises a first dielectric layer, a second dielectric layer, a third dielectric layer, a fourth dielectric layer and a fifth dielectric layer, wherein the first dielectric layer is located on a side of the first metal layer away from the second metal layer, the second dielectric layer is located between the first metal layer and the second metal layer, the third dielectric layer is located between the second metal layer and the third metal layer, the fourth dielectric layer is located between the third metal layer and the fourth metal layer, and the fifth dielectric layer is located on a side of the fourth metal layer away from the third metal layer; The total physical thickness of the first dielectric layer is Eo1, the total physical thickness of the second dielectric layer is Eo2, the total physical thickness of the third dielectric layer is Eo3, the total physical thickness of the fourth dielectric layer is Eo4 and the total physical thickness of the fifth dielectric layer is Eo5. The total physical thickness is Eo5; said Eo1, Eo2, Eo3, Eo4 and Eo5 satisfy at least one of the following conditions: (1)0.40 <Eo1 / Eo2<0.90; (2)0.40 <Eo1 / Eo3<0.90; (3)0.35 <Eo1 / Eo4<0.90; and (4)0.50 <Eo1 / Eo5<1.50。 5. The head-up display glass according to claim 4, characterized in that: The Eo1, Eo2, Eo3, Eo4 and Eo5 satisfy at least one of the following conditions: (5) 0.45≤Eo1 / Eo2≤0.60; (6) 0.50≤Eo1 / Eo3≤0.65; (7) 0.50 ≤ Eo1 / Eo4 ≤ 0.60; and (8)0.90≤Eo1 / Eo5≤1.

35.

6. The head-up display glass according to any one of claims 4 to 5, characterized in that: At least one of the first dielectric layer, the second dielectric layer, the third dielectric layer, the fourth dielectric layer and the fifth dielectric layer comprises at least two dielectric sublayers, and a refractive index of at least one of the dielectric sublayers is greater than or equal to 2.

0.

7. The head-up display glass according to claim 6, characterized in that: At least one of the dielectric sublayers is a TiOx layer or a NbOx layer, and the refractive index of the TiOx layer and the NbOx layer are both greater than or equal to 2.

3.

8. The head-up display glass according to any one of claims 6 to 7, characterized in that: At least one dielectric sub-layer included in at least one of the second dielectric layer, the third dielectric layer and the fourth dielectric layer is a visible light absorption layer, and a material of the visible light absorption layer is selected from at least one of NiCr, NiCrOx, Ti, ZnSn and Sn.

9. The head-up display glass according to claim 8, characterized in that: The physical thickness of the visible light absorbing layer is denoted as Eo6, and Eo6 satisfies the following condition: Eo6 / (Eo1+Eo2+Eo3+Eo4+Eo5)=0.001-0.

005.

10. The head-up display glass according to any one of claims 1 to 9, characterized in that: The head-up display glass meets at least one of the following characteristics: (1) the visible light reflectance of the head-up display glass measured from the fourth surface side is less than 10%; and (2) The visible light transmittance of the head-up display glass is greater than or equal to 70%.

11. The head-up display glass according to any one of claims 1 to 10, characterized in that: The 8° reflection color and the 65° reflection color of the head-up display glass are measured from the first surface side, and the a value in the Lab value of the 8° reflection color is less than 0, and the a value in the Lab value of the 65° reflection color is less than 0.

12. The head-up display glass according to any one of claims 1 to 11, characterized in that: The sheet resistance of the transparent conductive layer is less than or equal to 0.7Ω / □.

13. The head-up display glass according to any one of claims 1 to 12, characterized in that: The image brightness ratio of the head-up display glass to the projection light with a wavelength of 400nm to 700nm incident from the fourth surface side at an incident angle of 65° is C(400-700)≤0.17, or C(400-700)≤0.15, or C(400-700)≤0.

1.

14. The head-up display glass according to any one of claims 1 to 13, characterized in that: The image brightness ratio of the head-up display glass to the projection light with a wavelength of 600nm to 700nm incident from the fourth surface side at an incident angle of 65° is C(600-700)≤0.45, or C(600-700)≤0.4, or C(600-700)≤0.

3.

15. The head-up display glass according to any one of claims 1 to 14, characterized in that: The reflectivity of the head-up display glass to projection light with wavelengths of 469 nm, 532 nm and 629 nm incident from the side of the fourth surface at an incident angle of 65° is R4(469), R4(532) and R4(629), and the difference between the maximum and minimum values ​​of R4(469), R4(532) and R4(629) is less than or equal to 4%.

16. The head-up display glass according to any one of claims 1 to 15, characterized in that: The wedge-shaped profile has at least one wedge angle, and the wedge angle is 0.05 mrad to 0.6 mrad.

17. The head-up display glass according to any one of claims 1 to 16, characterized in that: The head-up display glass also includes a first busbar and a second busbar in direct electrical contact with the transparent conductive layer. A power supply inputs current into the transparent conductive layer through the first busbar and the second busbar. The power supply can provide a supply voltage of 12V to 60V.

18. A head-up display system, characterized in that: The head-up display glass comprises a projection device and any one of claims 1 to 17, wherein the projection device is used to generate projection light, wherein the projection light comprises 40% to 80% of S-polarized light and 20% to 60% of P-polarized light, and the projection light is incident on the fourth surface of the head-up display glass at an incident angle of 38° to 85°.

19. The head-up display system according to claim 18, characterized in that: The head-up display system also includes at least one sensor, which is installed on the fourth surface. The detection signal emitted and / or received by the sensor passes through the head-up display glass. The area of ​​the head-up display glass used for the detection signal to pass through is a signal transmission window, and the transparent conductive layer is not arranged in the signal transmission window.

Images