Head-up display glass and head-up display system

Abstract

This application relates to head-up display glass and head-up display system. The head-up display glass includes a laminated outer glass plate, a thermoplastic intermediate layer and an inner glass plate, and further includes a transparent conductive layer, the transparent conductive layer includes a first metal layer, a second metal layer, a third metal layer and a fourth metal layer laminated in order, the thickness of which satisfies 0.7 ≤ Ea4 / Ea1 ≤ 1.2, and the head-up display glass has a reflectivity of at least 15% for projected light rays incident from the fourth surface at an incident angle of 65°, the projected light rays include 40% to 80% S-polarized light and 20% to 60% P-polarized light.

Description

Technical Field

[0001] (Cross - reference to Related Applications) This application claims the priority of a Chinese patent application with application number 202310704072.3 and title "Head - up Display Glass and Head - up Display System" filed on June 14, 2023, and incorporates the entire content thereof into this application by reference.

[0002] This application relates to the field of head - up display technology, and particularly to head - up display glass and head - up display systems.

Background Art

[0003] With the development of the intelligence of automobiles, the requirements for the integrated functions of automotive glass have been increasing. Among them, research on head - up display (HUD) has become a trend based on the future development of many automobile manufacturers. Currently, a head - up display system usually includes a projection device and head - up display glass. The head - up display glass can be used as the front glass of the vehicle, and has an inner surface facing the inside of the vehicle and an outer surface facing the outside of the vehicle. The projection device projects image information onto the inner surface of the head - up display glass, and then enters the driver's eyes through the reflection of the head - up display glass. The projection light rays generated from conventional projection devices are mainly S - polarized light. This projection light is reflected at the inner surface of the glass from air and at the outer surface of the glass from air respectively, generating two offset images called the double - ghost phenomenon, which makes the HUD image unclear and reduces visual comfort.

[0004] At the same time, there is a demand for heat insulation or electric heating functions for vehicle windshields, and a transparent conductive layer can be added to the head-up display glass. The transparent conductive layer can consist of multiple metal layers and dielectric layers, and because the transparent conductive layer also reflects light rays, a third offset image called the triple ghosting phenomenon is formed, causing the HUD image to become even more blurred, obstructing the driver's view, negatively impacting safe driving, and further reducing the driver's visual comfort.

[0005] Most projection devices on the market employ TFT screens, and the projected light emitted is mainly S-polarized. Sunglasses typically transmit only P-polarized light and block S-polarized light, thus failing to meet the usage requirements of drivers who wear sunglasses. In recent years, to meet customer needs for sunglasses and market developments, major automobile manufacturers have been actively exploring P-polarized imaging and nonlinear polarization imaging. In the case of nonlinear polarization imaging, the projected light contains both S-polarized and P-polarized light, making it difficult to completely eliminate the triple ghosting phenomenon if a transparent conductive layer is placed on the head-up display glass. [Overview of the Initiative] [Problems that the invention aims to solve]

[0006] In view of this, based on the embodiments of the present application, we provide a head-up display glass and a head-up display system, and the technical proposal is as follows. [Means for solving the problem]

[0007] A head-up display glass comprising a laminated outer glass plate, a thermoplastic intermediate layer, 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 intermediate layer is located between the second surface and the third surface. The head-up display glass further includes a transparent conductive layer, the transparent conductive layer located on the second surface, or on the third surface, or within the thermoplastic intermediate layer, the thermoplastic intermediate layer having a wedge-shaped contour, and the transparent conductive layer includes a first metal layer, a second metal layer, a third metal layer, and a fourth metal layer, which are laminated in order. If the physical thickness of the first metal layer is Ea1 and the physical thickness of the fourth metal layer is Ea4, then Ea1 and Ea4 satisfy 0.7 ≤ Ea4 / Ea1 ≤ 1.2. The head-up display glass has a reflectivity of at least 15% with respect to projected light rays incident from the fourth surface at an incident angle of 65°, and the projected light rays include 40% to 80% S-polarization and 20% to 60% P-polarization.

[0008] A head-up display system comprising a projection device and the head-up display glass described above, wherein the projection device is used to generate projection rays, the projection rays comprising 40% to 80% S-polarization and 20% to 60% P-polarization, and the projection rays are incident on the fourth surface of the head-up display glass at an incident angle of 38° to 85°.

[0009] In some embodiments, the head-up display system further includes at least one sensor mounted on the fourth surface, and a detection signal transmitted and / or received by the sensor passes through the head-up display glass, and the region of the head-up display glass through which the detection signal passes is a signal-transmitting window, and the transparent conductive layer is not installed within the signal-transmitting window.

[0010] Details of one or more embodiments of the present application are described below, and other features, purposes and advantages of the present application will become apparent from this specification and its claims.

[0011] To more clearly describe the embodiments of the present application or the technical concepts in the prior art, the following briefly introduces the drawings necessary for describing the embodiments or the prior art. Clearly, the drawings in the following description are merely embodiments of the present application, and those skilled in the art can obtain other drawings without creative effort based on the disclosed drawings. [Brief explanation of the drawing]

[0012] [Figure 1] This is a schematic diagram showing the structure of a head-up display system provided in one embodiment of the present application. [Figure 2] This is a schematic diagram showing the cross-sectional structure of a head-up display glass provided in another embodiment of the present application. [Figure 3] This is a schematic diagram showing the cross-sectional structure of a transparent conductive layer provided in one embodiment of the present application. [Modes for carrying out the invention]

[0013] The technical concepts described herein will be clearly and completely explained below with reference to the accompanying drawings of the embodiments of this application. Clearly, the embodiments described are only some, and not all, embodiments of this application. All other embodiments that a person skilled in the art could obtain based on the embodiments of this application without requiring any creative effort are all within the scope of protection of this application.

[0014] Unless otherwise defined, all technical and scientific terms used herein have meanings that are generally understood by those skilled in the art. Terms used herein are for illustrative purposes only and are not intended to limit the invention.

[0015] [term] Unless otherwise specified or contradicted, terms or phrases used herein have the following meanings.

[0016] In the present application, unless specifically and explicitly limited, the meaning of "plural" is at least two, for example, two, three, etc. Unless specifically and explicitly limited, the meaning of "several" is at least one, for example, one, two, etc.

[0017] In the present application, for a numerical range, unless otherwise specified, the two endpoints of the numerical range are included.

[0018] In the present application, the "layer" may be understood as a single layer or a stack of multiple layers.

[0019] In the present application, the "incident angle" is the angle formed between the projection light beam generated by the projection device and the normal of the surface when the projection light beam enters one side of the head-up display glass.

[0020] In the present application, the "refractive index" is the refractive index of transmitted light at 550 nm.

[0021] Referring to FIG. 1, a head-up display system provided in an embodiment of the present application includes a projection device 100 and a head-up display glass 200. The projection device 100 is used to generate a projection light beam 101. The head-up display glass 200 includes a laminated outer glass plate 1, a thermoplastic intermediate layer 3, an inner glass plate 2, and a transparent conductive layer 4. The outer glass plate 1 has a first surface 111 and a second surface 112. The inner glass plate 2 has a third surface 121 and a fourth surface 122. The thermoplastic intermediate layer 3 is located between the second surface 112 and the third surface 121. The transparent conductive layer 4 includes a plurality of metal layers, and has a high transmittance for visible light, a high reflectance for infrared rays, and good conductive properties. Based on realizing the head-up display function, the head-up display glass has excellent heat insulation performance and further electric heating performance.

[0022] In this embodiment, the projected light ray 101 includes 40% to 80% S-polarization and 20% to 60% P-polarization, the projected light ray 101 is incident on the fourth surface 122 of the head-up display glass 200 at an incident angle of 38° to 85°, and the projected light ray 101 is reflected by the head-up display glass 200 and enters the human eye 300, so that the head-up display (HUD) image 400 located in front of the head-up display glass 200 is observed by the human eye. Specifically, the projected light ray 101 includes 40% S-polarization and 60% P-polarization, 50% S-polarization and 50% P-polarization, 60% S-polarization and 40% P-polarization, 70% S-polarization and 30% P-polarization, and 80% S-polarization and 20% P-polarization. Preferably, the projected light ray 101 includes 50% to 70% S-polarization and 30% to 50% P-polarization, satisfying the high-brightness requirement for the head-up display image while also meeting the requirements for use when the driver is wearing sunglasses.

[0023] To make it easier to understand, the outer glass plate 11, the inner glass plate 12, the thermoplastic intermediate layer 13, and the transparent conductive layer 14 are laminated along the thickness direction of the head-up display glass 200, with the first surface 111 of the outer glass plate 11 facing outwards from the car and located further from the thermoplastic intermediate layer 13 than the second surface 112, and the fourth surface 122 of the inner glass plate 12 facing inwards from the car and located further from the thermoplastic intermediate layer 13 than the third surface 121. Here, the thermoplastic intermediate layer 13 is sandwiched between the second surface 112 and the third surface 121 and is used to bond the outer glass plate 11 and the inner glass plate 12 together to form a laminated glass structure, and its material can be selected from polyvinyl butyral (PVB), ethylene vinyl acetate (EVA), ionic polymer film (SGP), etc. The thermoplastic intermediate layer 13 may be a single layer structure or a multilayer structure, for example, a two-layer structure, a three-layer structure, a four-layer structure, or even a five-layer structure. If the thermoplastic intermediate layer 13 is, for example, a three-layer PVB, then having a higher plasticizer content in one of the PVB layers provides sound insulation to the head-up display glass 200, and having a wedge-shaped contour in at least one of the PVB layers can eliminate some ghosting of the head-up display glass 200.

[0024] The transparent conductive layer 14 is located on the second surface 112, or on the third surface 121, or within the thermoplastic intermediate layer 13. In the present embodiment, as shown in FIG. 1, the transparent conductive layer 14 is directly disposed on the second surface 112. In another embodiment, as shown in FIG. 2, 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, and the material of the thermoplastic film can be selected from polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyimide (PI), cellulose triacetate (TAC), etc. The thermoplastic film on which the transparent conductive layer 14 is disposed is sandwiched between the second surface 112 and the third surface 121. Specifically, it may be located 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 on which the transparent conductive layer 14 is disposed is sandwiched between the two layers of transparent PVB. Here, the transparent conductive layer 14 may be deposited on the second surface 112, on the third surface 121, or on the thermoplastic film by a magnetron sputtering process.

[0025] The head-up display glass 200 of the present embodiment has no special requirements for the projection light beam 101 emitted from the projection device 100, can eliminate the limitations of conventional TFT screen projection, does not require a design for linear polarization of normal screen projection, and can be used in combination with more screen projections such as OLED and LCD. That is, the projection light beam 101 described in the present application is a mixed polarization including both S polarization and P polarization, such as natural light, partial polarization, circular polarization, elliptical polarization, etc., which can meet the high brightness requirements of the head-up display image and also meet the usage requirements when the driver wears sunglasses.

[0026] To make it easier to understand, when the projected light ray 101 forms the head-up display (HUD) image 400, reflections occur at the fourth surface 122, the transparent conductive layer 14, and the first surface 111, respectively. The image formed by the reflection at the fourth surface 122 becomes the main image of the HUD, the image formed by the reflection at the first surface 111 becomes the first ghost, and the image formed by the reflection at the transparent conductive layer 14 becomes the second ghost. In order to directly remove the first ghost, the thermoplastic intermediate layer 13 used in this embodiment has a wedge-shaped contour. Compared with conventional thermoplastic intermediate layers of equal thickness, the thermoplastic intermediate layer 13 with a wedge-shaped contour can eliminate visual ghosting by overlapping the first ghost with the main image of the HUD. In this embodiment, when the head-up display glass 200 is installed as the windshield of a vehicle, the thermoplastic intermediate layer 13 has a wedge-shaped contour in which the thickness at the upper end is greater than the thickness at the lower end. Preferably, the wedge-shaped contour comprises at least one wedge angle, the wedge angle being 0.05mrad to 0.6mrad. Specifically, the wedge-shaped contour comprises a certain wedge angle, for example, 0.05mrad, 0.1mrad, 0.15mrad, 0.2mrad, 0.25mrad, 0.3mrad, 0.35mrad, 0.4mrad, 0.45mrad, 0.5mrad, 0.55mrad, 0.6mrad, etc. The wedge-shaped contour may comprise a plurality of certain wedge angles, for example, two certain wedge angles, three certain wedge angles, or even more certain wedge angles. In the case of two certain wedge angles, the first wedge angle may be 0.38mrad to realize the HUD image, and the second wedge angle may be 0.10mrad to realize a camera window without perspective ghosting. In the case of three constant wedge angles, the first wedge angle for realizing the first HUD image may be 0.5 mrad, the first wedge angle for realizing the second HUD image may be 0.4 mrad, and the third wedge angle for realizing the third HUD image may be 0.2 mrad. In the interval with constant wedge angles, the thickness of the wedge-shaped contour changes linearly.To make it clear, the wedge-shaped contour has a continuously variable wedge angle, which causes the thickness of the wedge-shaped contour to change non-linearly, and the continuously variable wedge angle allows for a larger field of view (FOV), a larger image size, and a head-up display image free from visible ghosting.

[0027] 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, which are sequentially laminated along the thickness direction of the head-up display glass 200. In this embodiment, when the transparent conductive layer 14 is deposited on the second surface 112 by a magnetron sputtering process, the first dielectric layer 141 is deposited directly on the second surface 112, and the first metal layer 142, second dielectric layer 143, second metal layer 144, third dielectric layer 145, third metal layer 146, fourth dielectric layer 147, fourth metal layer 148, and fifth dielectric layer 149 are deposited away from the second surface 112 in that order. In another embodiment, when the first dielectric layer 141 is deposited directly onto the third surface 121 by a magnetron sputtering process, the first dielectric layer 141 is deposited directly onto the third surface 121, and separates from the third surface 121 in the order of 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. In yet another embodiment, when the transparent conductive layer 14 is deposited on a thermoplastic film by a magnetron sputtering process, the first dielectric layer 141 is deposited directly onto the thermoplastic film, and separates from the thermoplastic film in the order of 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.In response to the second ghost formed by the reflection of the transparent conductive layer 14, the present invention provides low reflectivity for projection rays 101 with wavelengths of 400nm to 700nm and 600nm to 700nm by designing the film structure of the transparent conductive layer 14. As a result, the head-up display glass 200 achieves an image brightness ratio C(400~700) ≤ 0.15 for projection rays 101 with wavelengths of 400nm to 700nm incident at an incident angle of 65° from one side of the fourth surface. The glass 200 achieves an image brightness ratio C(600~700) ≤ 0.3 for projected light rays 101 with a wavelength of 600nm~700nm incident at an incident angle of 65° from one side of the fourth surface. Taking into account that the head-up display glass 200 has heat insulation and electric heating functions, it significantly reduces the brightness and indistinguishability of ghosts formed by reflection from the transparent conductive layer 14, thereby contributing to achieving a visual ghost-free effect and 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 projected light rays 101 incident at an incident angle of 65° from one side of the fourth surface, such as 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, etc.

[0028] Here, 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 each independently selected from one or more of silver and silver alloys, wherein the silver alloy is preferably an alloy of silver with at least one of gold, aluminum, copper, indium, and platinum.

[0029] If the physical thickness of the first metal layer 142 is Ea1 and the physical thickness of the fourth metal layer 148 is Ea4, then Ea1 and Ea4 satisfy 0.7 ≤ Ea4 / Ea1 ≤ 1.2. To understand this, Ea4 / Ea1 may 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, 0.80 ≤ Ea4 / Ea1 ≤ 1. Even more preferably, 0.80 ≤ Ea4 / Ea1 ≤ 0.95.

[0030] If the physical thickness of the second metal layer 144 is Ea2 and the physical thickness of the third metal layer 146 is Ea3, then Ea1, Ea2, Ea3, and Ea4 satisfy at least one of the following conditions. (1) 0.60 ≤ Ea4 / Ea2 ≤ 0.80 To make it easier to understand, Ea4 / Ea2 can also be 0.60, 0.65, 0.70, 0.75, 0.80, etc.

[0031] (2) 0.60 ≤ Ea4 / Ea3 ≤ 0.80 To make it easier to understand, Ea4 / Ea3 can also be 0.60, 0.65, 0.70, 0.75, 0.80, etc.

[0032] (3) Ea1 + Ea2 + Ea3 + Ea4 ≥ 40 To make it understandable, the sum of the physical thicknesses of the four metal layers, Ea1 + Ea2 + Ea3 + Ea4, may be 40nm, 41nm, 42nm, 43nm, 44nm, 45nm, 46nm, 47nm, 48nm, 49nm, 50nm, 51nm, 52nm, 53nm, 54nm, 55nm, 56nm, etc. Preferably, 45nm ≤ Ea1 + Ea2 + Ea3 + Ea4 ≤ 55nm.

[0033] (4) At least one of Ea1, Ea2, Ea3, and Ea4 is 11 nm or less. To make it easier to understand, only one of Ea1, Ea2, Ea3, and Ea4 may be less than or equal to 11nm, for example, Ea4 ≤ 11nm, and only two of Ea1, Ea2, Ea3, and Ea4 may be less than or equal to 11nm, for example, Ea1 ≤ 11nm and Ea4 ≤ 11nm.

[0034] (5) The difference between the maximum and minimum values ​​of Ea1, Ea2, Ea3, and Ea4 is 5 nm or less. To ensure understanding, the difference between the maximum and minimum values ​​in Ea1, Ea2, Ea3, and Ea4 may be 3nm, 3.5nm, 4nm, 4.5nm, 5nm, etc.

[0035] Here, the first dielectric layer 141 is located on one 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 one side of the fourth metal layer 148 away from the third metal layer 146. The materials for 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 can each be independently selected from at least one of the following: oxides of the elements Zn, Mg, Sn, Ti, Nb, Zr, Ni, In, Al, Ce, W, Mo, Sb, and Bi, or nitrides, nitride oxides, and mixtures thereof of the elements Si, Al, Zr, Y, Ce, and La. Examples include 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, and the like. Selectively, 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 contain at least two sub-dielectric layers. For example, as shown in Figure 3, the first dielectric layer 141 contains two sub-dielectric layers, the second dielectric layer 143, the third dielectric layer 145, and the fourth dielectric layer 147 each contain four sub-dielectric layers, and the fifth dielectric layer 149 contains three sub-dielectric layers. To understand this, if each dielectric layer has a single-layer structure, its total physical thickness is the physical thickness of that layer. If each dielectric layer has a multilayer structure, its total physical thickness is the sum of the physical thicknesses of all the sub-dielectric layers in that layer.

[0036] Let Eo1 be the total physical thickness of the first dielectric layer, Eo2 be the total physical thickness of the second dielectric layer, Eo3 be the total physical thickness of the third dielectric layer, Eo4 be the total physical thickness of the fourth dielectric layer, and Eo5 be the total physical thickness of the fifth dielectric layer. Then Eo1, Eo2, Eo3, Eo4, and Eo5 satisfy at least one of the following conditions. (1) 0.40 <Eo1 / Eo2<0.90 To make it understandable, 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.

[0037] (2) 0.40 <Eo1 / Eo3<0.90 To make it understandable, 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.

[0038] (3) 0.35 <Eo1 / Eo4<0.90 To make it understandable, Eo1 / Eo4 may 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.

[0039] (4) 0.50 <Eo1 / Eo5<1.50 To make it understandable, Eo1 / Eo5 may 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.

[0040] In some embodiments, at least one of the first dielectric layer 141, second dielectric layer 143, third dielectric layer 145, fourth dielectric layer 147, and fifth dielectric layer 149 includes at least two sub-dielectric layers, and the refractive index of at least one of the sub-dielectric layers is 2.0 or higher. Preferably, the material of at least one of the sub-dielectric layers is TiOx or NbOx, and the refractive index of the TiOx layer and the NbOx layer is 2.3 or higher.

[0041] In some embodiments, at least one subdielectric 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, if the physical thickness of the visible light absorbing layer is Eo6, then Eo6 and Eo1, Eo2, Eo3, Eo4, and Eo5 satisfy Eo6 / (Eo1+Eo2+Eo3+Eo4+Eo5)=0.001~0.005, specifically, 0.001, 0.0015, 0.002, 0.0025, 0.003, 0.0035, 0.004, 0.0045, 0.005, etc.

[0042] Here, each of the multiple metal layers and the multiple dielectric layers can be deposited layer by layer by a magnetron sputtering process, and by optimizing the material and thickness of the metal and dielectric layers, the transparent conductive layer 14 can withstand subsequent high-temperature heat treatment and other bending processes, and the optical and mechanical properties of the resulting head-up display glass 200 can all meet the standards for use in vehicle glass.

[0043] In some embodiments, the visible light reflectance of the head-up display glass 200, measured from one side of the fourth surface, is less than 10%, specifically 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, etc., which prevents the instrument panel inside the vehicle from forming a sharp reflective image on the head-up display glass 200, and the reflective image of the instrument panel has a significant impact on driving safety and visual comfort.

[0044] In some embodiments, the visible light transmittance of the head-up display glass 200 is 70% or more, specifically 70%, 71%, 72%, 73%, 74%, 75%, 80%, 85%, etc., thereby meeting the safety usage standards for vehicle glass.

[0045] In some embodiments, the 8° and 65° reflective colors of the head-up display glass 200 are measured from one side of the first surface, and the value of a in the Lab value of the 8° reflective color is less than 0, and the value of a in the Lab value of the 65° reflective color is less than 0, thereby the head-up display glass 200 has an excellent appearance color.

[0046] In some embodiments, the sheet resistance of the transparent conductive layer 14 is 0.7Ω / □ or less, specifically 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 heat insulation performance. Preferably, the total solar energy transmittance of the head-up display glass 200 is 45% or less, specifically 38%, 39%, 40%, 41%, 42%, 43%, 44%, 45%, etc.

[0047] In some embodiments, the transparent conductive layer 14 provides the head-up display glass 200 with excellent electric heating performance, enabling rapid defrosting, fogging, ice removal, snow removal, and other similar functions. To achieve electric heating performance, the head-up display glass 200 includes first and second busbars directly electrically connected to the transparent conductive layer 14, and a power supply inputs current into the transparent conductive layer via the first and second busbars, and the power supply can provide a supply voltage of 12V to 60V.

[0048] In some embodiments, the head-up display system includes at least one sensor mounted on the fourth surface 122, and a detection signal transmitted and / or received by the sensor passes through the head-up display glass 200, the region of the head-up display glass 200 through which the detection signal passes is a signal-transmitting window, and the transparent conductive layer 14 is not installed within the signal-transmitting window so that the transparent conductive layer 14 does not interfere with or block the detection signal. The absence of the transparent conductive layer 14 within the signal-transmitting window can be achieved by a film removal process, which may employ shielding and covering before coating, or laser removal, friction removal, or chemical etching removal after coating. Here, the sensor may be a visible light camera, a thermal imaging camera, a laser radar, a millimeter-wave radar, etc.

[0049] In this application, the projection device 100 projects using three optical paths of RGB (red, green, and blue), and the wavelength of the projection light rays 101 is 380 nm to 780 nm, thereby enabling the display of images of any color. To significantly reduce the brightness of ghosts formed by reflection from the transparent conductive layer 14 and achieve a ghost-free viewing effect, the head-up display glass 200 preferably has an image brightness ratio C(400~700) ≤ 0.17 for projection light rays 101 with wavelengths of 400 nm to 700 nm incident at an incident angle of 65° from one side of the fourth surface. Specifically, C(400~700) ≤ 0.17, such as 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, and the smaller the image brightness ratio C(400~700), the easier it is to obtain a ghost-free viewing effect. More preferably, C(400~700) ≤ 0.16. More preferably, C(400~700) ≤ 0.15. Here, the image brightness ratio C(400~700) can be determined using the calculation C(400~700) = Cf(400~700) / C4(400~700), where C4(400~700) represents the brightness of the head-up display image after the first ghost and the HUD main image overlap, and Cf(400~700) represents the brightness of the second ghost formed by reflection from the transparent conductive layer. C4(400~700) and Cf(400~700) can be determined by measuring the brightness with a luminance meter based on the A light source and a 400nm~700nm filter.

[0050] To reduce the recognition rate of ghosting formed by reflection from the transparent conductive layer 14, preferably, the head-up display glass 200 has an image brightness ratio C(600~700) ≤ 0.45 for projected light rays 101 with a wavelength of 600 nm to 700 nm incident at an incident angle of 65° from one side of the fourth surface, specifically 0.45, 0.44, 0.43, 0.42, 0.41, 0. Examples include 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, and 0.15. The smaller the image brightness ratio C(600~700), the easier it is to obtain an effect that eliminates visible ghosting. More preferably, C(600~700) ≤ 0.4. Even more preferably, C(600~700) ≤ 0.35. Here, the image brightness ratio C(600~700) can be determined using the calculation C(600~700) = Cf(600~700) / C4(600~700), where C4(600~700) represents the brightness of the head-up display image after the first ghost and the HUD main image overlap, and Cf(600~700) represents the brightness of the second ghost formed by reflection from the transparent conductive layer. C4(600~700) and Cf(600~700) can be determined by measuring the brightness with a luminance meter based on the A light source and a 600nm~700nm filter.

[0051] In order to achieve the most neutral color display possible for the HUD image, the head-up display glass 200 has reflectances R4(469), R4(532), and R4(629) for projection light rays 101 with wavelengths of 469nm, 532nm, and 629nm incident at an incident angle of 65° from one side of the fourth surface. Preferably, the difference between the maximum and minimum values ​​of R4(469), R4(532), and R4(629) is 4% or less, specifically 4%, 3.5%, 3%, 2.5%, 2%, 1.5%, and 1%. The smaller the difference between the maximum and minimum values ​​of R4(469), R4(532), and R4(629), the easier it is to obtain a smooth reflection spectrum, thereby achieving neutral color display.

[0052] In summary, the head-up display glass and head-up display system according to the embodiment of the present application, through the design of the transparent conductive layer, have a low reflectivity for projected light rays with wavelengths of 400nm to 700nm and 600nm to 700nm. Taking into account that the head-up display glass has heat insulation and electric heating functions, this significantly reduces the brightness and recognizability of ghosts formed by the reflection of the transparent conductive layer, which is advantageous in achieving an effect of no visible ghosting, and improving thermal comfort, visual comfort, and driving safety.

[0053] At the same time, this invention eliminates the limitations of conventional TFT screen projection, as it does not require any special requirements for the projected light emitted from the projection device. It does not require a design that linearly polarizes the light, unlike normal screen projection, and can be used in conjunction with a wider range of screen projections such as OLEDs and LCDs, meeting the requirements for use when occupants in a vehicle wear sunglasses.

[0054] (Comparative Examples 1-2 and 1-5) An outer glass plate 11, a thermoplastic intermediate layer 13, and an inner glass plate 12 are prepared. Both the outer glass plate 11 and the inner glass plate 12 are made of transparent glass with a thickness of 2.1 mm, and the thermoplastic intermediate layer 13 is made of transparent wedge-shaped PVB with an average thickness of 0.76 mm. The transparent conductive layer 14 of Comparative Examples 1-2 and Examples 1-5 shown in Table 1 is deposited on the second surface 112 or the third surface 121 by a magnetron sputtering process. Then, the glass is processed and manufactured according to the automotive glass manufacturing process to obtain a head-up display glass equipped with the transparent conductive layer 14 of Comparative Examples 1-2 and Examples 1-5.

[0055] [Table 1] TIFF2026521861000003.tif110170

[0056] Based on the transparent conductive layers of Comparative Examples 1-2 and Examples 1-5 shown in Table 1, the film structure design conditions that satisfy the physical thickness Ea1 of the first metal layer, Ea2 of the second metal layer, Ea3 of the third metal layer, and Ea4 of the fourth metal layer are calculated, and the film structure design conditions that satisfy the physical thickness Eo1 of the first dielectric layer, Eo2 of the second dielectric layer, Eo3 of the third dielectric layer, Eo4 of the fourth dielectric layer, and Eo5 of the fifth dielectric layer are calculated, and the calculation results are entered in Table 2.

[0057] [Table 2]

[0058] A head-up display system is constructed by combining the head-up display glass 200 equipped with the transparent conductive layer 14 in Comparative Examples 1-2 and Examples 1-5 with a projection device 100. The projection device 100 generates a projection ray 101 containing 50% P-polarization and 50% S-polarization, and the projection ray is incident on the fourth surface 122 of the head-up display glass 200 at an incident angle of 38° to 85°. By adjusting the position of the projection device 100 and the incident angle of the projection ray 101, the clearest possible head-up display image can be achieved for the observer. The following optical performances are measured, and the measurement results are recorded in Table 3.

[0059] Based on the visible light transmittance standard TL:ISO9050, the transmittance of the head-up display glass for visible light in the 380nm to 780nm range, incident at an incident angle of 8°, is measured and calculated.

[0060] Based on the visible light reflectance standard RL:ISO9050, the reflectance of the head-up display glass for visible light in the 380nm to 780nm range, incident at an incident angle of 8°, is measured and calculated from one side of the fourth surface.

[0061] Based on the projection light reflectance R65:ISO9050 standard, the reflectance of the head-up display glass for projection light in the range of 380nm to 780nm incident at an incident angle of 65° is measured and calculated from one side of the fourth surface.

[0062] Reflected color a(8): Calculated according to the CIE Lab color model, based on a D65 light source and a 10° viewing angle, when measured from one side of the first surface at an incident angle of 8°, where the value of a represents the red and green values, and the value of b represents the yellow and blue values.

[0063] Reflected color a(65): Calculated according to the CIE Lab color model based on a D65 light source and a 10° field of view when measured from one side of the first surface at an incident angle of 65°, where the value of a represents the red and green values, and the value of b represents the yellow and blue values.

[0064] The image brightness ratio C(400~700) is calculated using the formula C(400~700) = Cf(400~700) / C4(400~700).

[0065] C4(400~700): Based on an A light source and a 400nm~700nm filter, a luminance meter is used to measure the brightness of the head-up display image formed by reflection from the head-up display glass.

[0066] Cf(400~700): Based on the A light source and a 400nm~700nm filter, a luminance meter is used to measure the luminance of the second ghost formed by reflection from the transparent conductive layer.

[0067] The image brightness ratio C(600~700) is calculated using the formula C(600~700) = Cf(600~700) / C4(600~700).

[0068] C4(600~700): Based on an A light source and a 600nm~700nm filter, a luminance meter is used to measure the brightness of the head-up display image formed by reflection from the head-up display glass.

[0069] Cf(600~700): Based on the A light source and a 600nm~700nm filter, a luminance meter is used to measure the luminance of the second ghost formed by reflection from the transparent conductive layer.

[0070] R4(469), R4(532), R4(629): Based on ISO9050, the reflectance of the head-up display glass for projected light rays with wavelengths of 469 nm, 532 nm, and 629 nm incident at an incident angle of 65° is measured and calculated from one side of the fourth surface.

[0071] [Table 3]

[0072] As can be seen from Tables 2 and 3, Comparative Example 1 employs a transparent conductive layer with Ea4 / Ea1 > 1.2, resulting in a reddish reflective color a(65) and an image brightness ratio C(400~700) greater than 0.18. Consequently, Comparative Example 1 fails to achieve a visually ghost-free effect, even considering that the head-up display glass is intended to have heat insulation or electric heating functions, and the head-up display glass does not possess a superior appearance.

[0073] Comparative Example 2 employs a transparent conductive layer with Ea4 / Ea1 > 1.2, Ea4 / Ea2 > 1.2, and Ea4 / Ea2 > 1.2. The resulting head-up display glass exhibits strong red reflections in both a(8) and a(65), an image luminance ratio C(400~700) greater than 0.5, an image luminance ratio C(600~700) greater than 1, a visible light reflectance RL greater than 10%, and a difference of 10% between the maximum and minimum values ​​of R4(469), R4(532), and R4(629). Consequently, Comparative Example 2 fails to achieve a visual ghost-free effect despite the head-up display glass having thermal insulation and electric heating functions. The head-up display glass lacks excellent appearance color, the head-up display image fails to achieve neutral color display, and the reflected image of the instrument panel is also relatively poor.

[0074] In Examples 1-5, by designing the film structure for the transparent conductive layer, the resulting head-up display glass has a reflective color a(8) and a(65) of less than 0, a visible light reflectance RL of less than 10%, a projected light reflectance R65 of greater than 15%, an image brightness ratio C(400-700) of 0.15 or less, an image brightness ratio C(600-700) of 0.3 or less, and the difference between the maximum and minimum values ​​of R4(469), R4(532), and R4(629) is less than 4%. In Example 2, the difference between the maximum and minimum values ​​of R4(469), R4(532), and R4(629) is less than 2%, and in Example 3, the image brightness ratio C(400~700) is 0.1 or less, and C(600~700) is 0.2 or less. Thus, in Examples 1-5, taking into account that the head-up display glass has heat insulation and electric heating functions, it is possible to achieve an effect of no visible ghosting, the head-up display glass has excellent appearance color, and the head-up display image can achieve neutral color display.

[0075] The technical features of the embodiments described above can be combined in any way, and for the sake of brevity, not all possible combinations of the technical features in the embodiments described above have been explained. However, as long as these combinations of technical features are not contradictory, they should be considered to fall within the scope described herein.

[0076] The embodiments described above are merely examples of some embodiments of the present application, and although their descriptions are specific and detailed, they should not be interpreted as limiting the scope of protection of the invention. Furthermore, a person skilled in the art can make some modifications and improvements as long as they do not deviate from the spirit of the present application, and these too fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be the same as that of the claims.

Claims

1. The head-up display glass comprises a laminated outer glass plate, a thermoplastic intermediate layer, 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 intermediate layer is located between the second surface and the third surface. The head-up display glass further comprises a transparent conductive layer, the transparent conductive layer located on the second surface, or on the third surface, or within the thermoplastic intermediate layer, the thermoplastic intermediate layer having a wedge-shaped contour, and the transparent conductive layer comprises a first metal layer, a second metal layer, a third metal layer, and a fourth metal layer, which are laminated in order. If the physical thickness of the first metal layer is Ea1 and the physical thickness of the fourth metal layer is Ea4, then Ea1 and Ea4 satisfy 0.7 ≤ Ea4 / Ea1 ≤ 1.

2. The head-up display glass is characterized in that it has a reflectivity of at least 15% with respect to projected light rays incident from the fourth surface at an incident angle of 65°, and the projected light rays include 40% to 80% S-polarization and 20% to 60% P-polarization.

2. If the physical thickness of the second metal layer is Ea2 and the physical thickness of the third metal layer is Ea3, then Ea1, Ea2, Ea3 and Ea4 are, (1) The condition that 0.80 ≤ Ea4 / Ea1 ≤ 1.1, (2) The condition that 0.60 ≤ Ea4 / Ea2 ≤ 0.80, (3) The condition that 0.60 ≤ Ea4 / Ea3 ≤ 0.80, (4) The condition that Ea1 + Ea2 + Ea3 + Ea4 ≥ 40 nm, (5) The condition that at least one of Ea1, Ea2, Ea3 and Ea4 is 11 nm or less, (6) The head-up display glass according to claim 1, characterized in that it satisfies at least one of the following conditions: the difference between the maximum and minimum values ​​of Ea1, Ea2, Ea3, and Ea4 is 5 nm or less.

3. The head-up display glass according to claim 1 or 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 types of silver and silver alloys.

4. 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 one 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 one side of the fourth metal layer away from the third metal layer. If 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, then Eo1, Eo2, Eo3, Eo4, and Eo5 are, (1) The condition that 0.40 < Eo1 / Eo2 < 0.90, (2) The condition that 0.40 < Eo1 / Eo3 < 0.90, (3) The condition that 0.35 < Eo1 / Eo4 < 0.90, and (4) The head-up display glass according to any one of claims 1 to 3, characterized in that it satisfies at least one of the conditions that 0.50 < Eo1 / Eo5 < 1.

50.

5. The aforementioned Eo1, Eo2, Eo3, Eo4 and Eo5 are, (5) The condition that 0.45 ≤ Eo1 / Eo2 ≤ 0.60, (6) The condition that 0.50 ≤ Eo1 / Eo3 ≤ 0.65, (7) The condition that 0.50 ≤ Eo1 / Eo4 ≤ 0.60, and (8) The head-up display glass according to claim 4, characterized in that it satisfies at least one of the conditions that 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 includes at least two sub-dielectric layers, and the refractive index of at least one of the sub-dielectric layers is 2.0 or higher.

7. The head-up display glass according to claim 6, characterized in that at least one of the subdielectric layers is a TiOx layer or an NbOx layer, and the refractive index of both the TiOx layer and the NbOx layer is 2.3 or higher.

8. The head-up display glass according to claim 6 or 7, characterized in that at least one sub-dielectric layer included in at least one of the second dielectric layer, the third dielectric layer, and the fourth dielectric layer 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.

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

005.

10. The aforementioned head-up display glass is (1) The visible light reflectance of the head-up display glass measured from the fourth surface is less than 10%, and (2) The visible light transmittance of the head-up display glass is 70% or more, and the head-up display glass according to any one of the above, is characterized in that it satisfies at least one of these conditions.

11. The head-up display glass according to any one of claims 1 to 10, characterized in that, when measuring the 8° reflectance color and the 65° reflectance color of the head-up display glass from the first surface, the value of a in the Lab value of the 8° reflectance color is less than 0, and the value of a in the Lab value of the 65° reflectance 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 0.7 Ω / □ or less.

13. The head-up display glass according to any one of claims 1 to 12, characterized in that the image brightness ratio C(400-700) ≤ 0.17, or C(400-700) ≤ 0.15, or C(400-700) ≤ 0.10 for projected light rays with wavelengths of 400 nm to 700 nm incident from the fourth surface at an incident angle of 65°.

14. The head-up display glass according to any one of claims 1 to 13, characterized in that the image brightness ratio C(600-700) ≤ 0.45, or C(600-700) ≤ 0.40, or C(600-700) ≤ 0.30 for projected light rays with a wavelength of 600 nm to 700 nm incident from the fourth surface at an incident angle of 65°.

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

16. The head-up display glass according to any one of claims 1 to 15, characterized in that the wedge-shaped contour comprises at least one wedge angle, the wedge angle being 0.05 mrad to 0.6 mrad.

17. The head-up display glass according to any one of claims 1 to 16, further comprising a first busbar and a second busbar directly electrically connected to the transparent conductive layer, wherein a power supply inputs current into the transparent conductive layer via the first busbar and the second busbar, and the power supply provides a supply voltage of 12V to 60V.

18. A head-up display system comprising a projection device and a head-up display glass according to any one of claims 1 to 17, wherein the projection device is used to generate projection rays, the projection rays comprising 40% to 80% S-polarized light and 20% to 60% P-polarized light, and the projection rays 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, further comprising at least one sensor mounted on the fourth surface, wherein a detection signal transmitted and / or received by the sensor passes through the head-up display glass, and the region of the head-up display glass through which the detection signal passes is a signal-transmitting window, and the transparent conductive layer is not installed within the signal-transmitting window.

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