Laminated glass, projection system, and vehicle

Abstract

This application provides laminated glass, a projection system, and a vehicle. The laminated glass includes a first glass plate, an intermediate adhesive layer, a second glass plate, a functional layer, and an adjustment layer. This application achieves image clarity by setting a first wedge shape and defining a first preset range, ensuring that the reflected primary image and the reflected secondary image of the functional layer coincide. Furthermore, the reflective nature of the functional layer enhances brightness. The high degree of overlap between the reflected primary image and the reflected secondary image facilitates color correction of the superimposed image, resulting in a better color-shift-free display. Additionally, the adjustment layer significantly reduces the brightness of the reflected secondary image of the glass plate, even eliminating ghosting, thus avoiding image blurring caused by insufficient overlap between the reflected secondary image and the primary image. This results in a clear display image and improved driving safety.

Description

Technical Field

[0001] This application belongs to the field of laminated glass technology, specifically relating to laminated glass, projection systems, and vehicles. Background Technology

[0002] With the application of vehicle head-up displays (HUDs), drivers can reduce the need to look down at the dashboard or related information, making it easier for them to switch their eyes between near and far objects. This reduces the need to look down at the dashboard, allowing drivers to concentrate their attention on the road and improving driving safety.

[0003] The HUD optical path is as follows: Image information is projected onto the image display area by a projection device. The projected light is reflected by the inner surface of the laminated glass and enters the human eye to form the primary image. However, since the laminated glass is a transparent medium, a secondary reflective ghost image is also formed after reflection by the outer surface of the laminated glass into the human eye. This is also known as a reflection ghost or a secondary image reflected by the glass plate.

[0004] Meanwhile, to provide vehicles with good heat insulation and functions such as heated windshields to remove rain and snow, laminated glass typically integrates the functional layer onto the glass. Since the functional layer, being made of metal, usually has a different refractive index than the glass sheet, it not only blocks solar energy but also creates a secondary image reflected by the functional layer. The driver will simultaneously see multiple nearly overlapping images composed of the primary image, the secondary image reflected by the glass sheet, and the secondary image reflected by the functional layer. This results in a blurred, color-distorted image, a feeling of dizziness, a poor driving experience, and compromised driving safety. Summary of the Invention

[0005] In view of this, the first aspect of this application provides a laminated glass, the laminated glass comprising a first glass plate, an intermediate adhesive layer, and a second glass plate stacked sequentially, the laminated glass further comprising a functional layer disposed between the intermediate adhesive layer and the second glass plate; The first glass plate includes a first surface facing away from the intermediate adhesive layer and a second surface close to the intermediate adhesive layer; the second glass plate includes a third surface close to the intermediate adhesive layer and a fourth surface facing away from the intermediate adhesive layer. The laminated glass has an image display area for receiving and reflecting projected light to form a primary image, and the projected light also forms a secondary image of the functional layer. At least within the area of ​​the image display area, the second glass plate has a first wedge shape for adjusting the secondary image of the functional layer so that the displacement difference between the secondary image of the functional layer and the primary image of the reflection is within a first preset range, the first preset range being ≤1.6 arcmin. The laminated glass also includes an adjustment layer located in the image display area. The adjustment layer is disposed between the first glass plate and the functional layer, and is used to convert S-polarized light into P-polarized light.

[0006] Wherein, the wedge angle of the first wedge is ≤0.295mrad.

[0007] The projected light also forms a glass plate reflective sub-image. At least within the image display area, the first glass plate and / or the intermediate adhesive layer have a second wedge shape. The second wedge shape is used to adjust the glass plate reflective sub-image so that the displacement difference between the glass plate reflective sub-image and the reflective main image is within a second preset range.

[0008] Wherein, the first glass plate and / or the second glass plate have a wedge angle, and the wedge angle of the first glass plate and / or the second glass plate has a first local wedge angle fluctuation standard deviation σ1 in the image display area, and the first local wedge angle fluctuation standard deviation σ1 satisfies the following condition: 3σ1≤0.08mrad / 10mm.

[0009] The intermediate adhesive layer has a wedge angle, and the wedge angle of the intermediate adhesive layer has a second local wedge angle fluctuation standard deviation σ2 within the image display area. The second local wedge angle fluctuation standard deviation σ2 satisfies the following condition: 3σ2≤0.15mrad / 10mm.

[0010] The first glass plate and / or the second glass plate with the wedge angle have a spray direction, which is vertical or horizontal.

[0011] Wherein, the vertical field of view (VFOV) of the image display area is ≤7°.

[0012] The conversion efficiency of the adjustment layer for the S-polarized light is ≥85%. And / or, the thickness of the adjustment layer is 2μm~200μm; And / or, the internal reflectivity of the adjustment layer in the laminated glass is ≤2%.

[0013] The adjustment layer is selected from half-wave plate film.

[0014] The half-wave plate film is selected from at least one of polyimide-based thin film half-wave plate, liquid crystal polymer thin film half-wave plate, indium tin oxide thin film half-wave plate, quartz-based flexible thin film half-wave plate, nanocomposite thin film half-wave plate, graphene-oxide composite thin film half-wave plate, and ultrathin dielectric metasurface half-wave plate.

[0015] The intermediate adhesive layer includes a first adhesive layer and a second adhesive layer, and the first glass plate, the first adhesive layer, the adjustment layer, the second adhesive layer, and the second glass plate are stacked in sequence.

[0016] Wherein, the sum of the thicknesses of the first adhesive layer and the second adhesive layer is 0.38 mm to 2.28 mm; And / or, the thickness ratio K of the first adhesive layer to the second adhesive layer satisfies: K=1±0.5.

[0017] The laminated glass has a reflection spectrum for the projected light, and the difference between the maximum and minimum reflectance values ​​in the 450nm~630nm wavelength band is PV≤6%.

[0018] Wherein, the visible light reflectance ratio CR1 of the functional layer reflective sub-image of the image display area relative to the reflective primary image is ≥8%.

[0019] Wherein, the visible light reflectance ratio CR2 of the glass plate reflecting the secondary image in the image display area relative to the primary image is ≤10%.

[0020] Wherein, the chroma C of the functional layer reflective sub-image * ab ≤40.

[0021] The incident angle β of the projected light ray satisfies the following condition: 45°<β≤70°.

[0022] Wherein, the thickness of the second glass plate is ≤2.1mm; And / or, at least within the area of ​​the image display region, a coloring material is provided between the first surface and the functional layer, the coloring material having a visible light transmittance of ≥50%, ≥60%, or ≥70%; And / or, the total solar transmittance (TTS) of the laminated glass is ≤50%.

[0023] The second aspect of this application provides a projection system, which includes a projection device and a laminated glass as provided in the first aspect of this application. The projection device is disposed on the side of the second glass plate away from the intermediate adhesive layer. The projection device is used to generate projection light, which includes S-polarized light. The proportion of S-polarized light in the projection light is ≥75%. The image display area is used to receive and reflect the projection light to form a reflected main image.

[0024] A third aspect of this application provides a vehicle comprising a body and a laminated glass as provided in the first aspect of this application, the laminated glass being disposed on the body.

[0025] The laminated glass, projection system, and vehicle provided in this application, by setting a first wedge and defining a first preset range, make the reflected primary image and the reflected secondary image of the functional layer coincide, resulting in a clear displayed image. Furthermore, due to the reflectivity of the functional layer, brightness enhancement is also achieved. Moreover, the high degree of overlap between the reflected primary image and the reflected secondary image of the functional layer facilitates adjustment of the projection device to achieve color correction of the superimposed image, resulting in a better color-shift-free displayed image. In addition, the use of an adjustment layer significantly weakens the brightness of the reflected secondary image of the glass plate, and even eliminates the ghosting of the reflected secondary image of the glass plate, avoiding image blurring caused by insufficient overlap accuracy between the reflected secondary image and the reflected primary image of the glass plate. Thus, a clear displayed image can be observed, improving driving safety. Attached Figure Description

[0026] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the embodiments of this application will be described below.

[0027] Figure 1 This is a schematic diagram of the structure of laminated glass provided in one embodiment of this application.

[0028] Figure 2 This is a cross-sectional schematic diagram of laminated glass provided in one embodiment of this application.

[0029] Figure 3 This is a schematic diagram of the detection device provided in one embodiment of this application.

[0030] Figure 4 The emission spectra S(λ) of different projection devices provided in this application.

[0031] Labeling: laminated glass 1, image display area 10, first glass plate 11, intermediate adhesive layer 12, first adhesive layer 121, second adhesive layer 122, second glass plate 13, functional layer 14, adjustment layer 15, projection device 21, detection device 3, first optical prism 311, second optical prism 312, first anti-reflection optical element 321, second anti-reflection optical element 322, third anti-reflection optical element 323. Detailed Implementation

[0032] The following are preferred embodiments of this application. It should be noted that, for those skilled in the art, several improvements and modifications can be made without departing from the principles of this application, and these improvements and modifications are also considered to be within the scope of protection of this application.

[0033] Before introducing the technical solution of this application, let's go over the technical issues in related technologies in detail.

[0034] In one related technology, a wedge-shaped intermediate film PVB and / or a wedge-shaped glass sheet can be used to make the secondary image reflected by the glass plate overlap with the primary image as much as possible. The secondary image reflected by the other functional layer, which cannot overlap, is reduced in brightness by using a special film system design, a specific functional layer, or a specific absorption layer, so that it is not easily perceived by the human eye.

[0035] Although the brightness of the functional layer reflective sub-image is reduced in related technologies, it is still visible in some scenarios. The functional layer reflective sub-image is difficult to overlap well with the glass plate reflective sub-image and the main reflective image. In actual products, the HUD image still has a separated functional layer reflective sub-image. The color abnormality of the functional layer reflective sub-image is easily noticed by people, i.e., color cast / blurring and other problems.

[0036] In view of this, in order to solve the above problems, please refer to the following: Figures 1-2 This embodiment provides a laminated glass 1, which includes a first glass plate 11, an intermediate adhesive layer 12, and a second glass plate 13 stacked sequentially. The laminated glass 1 also includes a functional layer 14, which is disposed between the intermediate adhesive layer 12 and the second glass plate 13.

[0037] The first glass plate 11 includes a first surface facing away from the intermediate adhesive layer 12 and a second surface close to the intermediate adhesive layer 12, and the second glass plate 13 includes a third surface close to the intermediate adhesive layer 12 and a fourth surface facing away from the intermediate adhesive layer 12.

[0038] The laminated glass 1 has an image display area 10, which is used to receive and reflect projected light to form a reflected primary image. The projected light also forms a functional layer reflected secondary image. At least within the range of the image display area 10, the second glass plate 13 has a first wedge shape, which is used to adjust the functional layer reflected secondary image so that the displacement difference between the functional layer reflected secondary image and the reflected primary image is within a first preset range, where the first preset range is ≤1.6 arcmin.

[0039] The laminated glass 1 further includes an adjustment layer 15 located in the image display area 10. The adjustment layer 15 is disposed between the first glass plate 11 and the functional layer 14, and the adjustment layer 15 is used to convert S-polarized light into P-polarized light.

[0040] The laminated glass 1 has an image display area 10, which receives and reflects projected light to form a primary image. The projected light also forms a secondary image reflected by the glass plate and a secondary image reflected by the functional layer. The image display area 10 can display vehicle driving information, various patterns, or play videos, and can be used in various scenarios such as welcoming guests, creating atmosphere, watching movies, and office work. Optionally, it can be used to display driving parameters, including vehicle speed, engine speed, fuel consumption, tire pressure, warning information, and mileage. It can also be used to display weather temperature and entertainment information, and can be used for dynamic navigation, night vision, and real-view maps. Along the stacking direction of the laminated glass 1, the image display area 10 is at least partially covered by the functional layer 14. The image display area 10 has a primary image reflective layer that forms the primary image and a functional layer 14 that forms the secondary image reflected by the functional layer.

[0041] Optionally, the laminated glass 1 has at least one image display area 10. For example, the number of image display areas 10 can be one, or multiple, with the multiple image display areas 10 spaced apart. The number of image display areas 10 can be designed according to the actual product.

[0042] Optionally, the image display area 10 is located in the bottom region of the laminated glass 1, and / or in the top region of the laminated glass 1, and / or in the left region of the laminated glass 1, and / or in the right region of the laminated glass 1.

[0043] Optionally, the projected light includes S-polarized light, and the proportion of S-polarized light in the projected light is ≥75%.

[0044] The proportion of S-polarized light in the projected light can be exemplified by, for example, 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99%. Preferably, the proportion of S-polarized light in the projected light is ≥95%. More preferably, the proportion of S-polarized light in the projected light is ≥97%.

[0045] S-polarized light naturally possesses high reflectivity when incident at an oblique angle, giving it an inherent advantage. The higher the proportion of S-polarized light in the projection light, the higher the proportion converted to P-polarized light after adjustment layer 15, resulting in a dimmer secondary image reflected by the glass plate. Furthermore, a higher proportion of S-polarized light in the projection light leads to higher reflectivity of the primary image, higher brightness at eye level, lower energy consumption of the projection system, and a corresponding reduction in the brightness requirement of the projection light source.

[0046] Specifically, the first glass plate 11 serves as the outer glass plate of the laminated glass 1. The first glass plate 11 has a first surface and a second surface. The first surface is away from the intermediate adhesive layer 12 and is in contact with the external environment of the vehicle, while the second surface is close to the intermediate adhesive layer 12. The second glass plate 13 serves as the inner glass plate of the laminated glass 1. The second glass plate 13 has a third surface and a fourth surface. The third surface is close to the intermediate adhesive layer 12, while the fourth surface is away from the intermediate adhesive layer 12 and is in contact with the internal environment of the vehicle.

[0047] Furthermore, the primary image reflective layer is the fourth surface, or the primary image reflective layer is a reflective structure located on the fourth surface. The fourth surface is the surface of the second glass plate 13 that faces away from the first glass plate 11.

[0048] Optionally, the first glass plate 11 is transparent glass or colored glass, the thickness of the first glass plate 11 is 0.7mm to 4mm, and the visible light transmittance of the first glass plate 11 is greater than or equal to 70%. The second glass plate 13 is transparent glass or colored glass, the thickness of the second glass plate 13 is 0.7mm to 4mm, and the visible light transmittance of the second glass plate 13 is greater than or equal to 70%.

[0049] Preferably, the thickness of the second glass plate 13 is ≤2.1mm, specifically, it can be 2.1mm, 2mm, 1.8mm, 1.6mm, 1.4mm, 1.2mm, or 0.8mm, etc. More preferably, the thickness of the second glass plate 13 is ≤1.6mm, ≤1.4mm, ≤1.2mm, or ≤0.8mm.

[0050] This embodiment uses a thinner second glass plate 13, which makes the deviation between the functional layer reflective sub-image and the reflective main image smaller, and makes it easier for the functional layer reflective sub-image and the reflective main image to overlap, so as to obtain a clearer display image and improve driving safety.

[0051] Preferably, at least within the image display area 10, a coloring material is provided between the first surface and the functional layer 14, wherein the visible light transmittance of the coloring material is ≥50%, ≥60%, or ≥70%.

[0052] Examples of visible light transmittance for coloring materials include 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, and 90%.

[0053] Specifically, the coloring material can be a first glass plate 11 that is colored on its own, or a colored intermediate adhesive layer 12, or an additional coloring film layer.

[0054] More preferably, the first glass plate 11 and / or the intermediate adhesive layer 12 are coloring layers.

[0055] For example, the first glass plate 11 may be light green or dark green. Another example is the intermediate adhesive layer 12, which may be a light gray interlayer film.

[0056] This embodiment reduces the secondary image reflected by the glass plate by providing a coloring material between the first surface and the functional layer 14, thereby making the displayed image clearer.

[0057] The intermediate adhesive layer 12 is a transparent or colored thermoplastic polymer film. Optionally, the thickness of the intermediate adhesive layer 12 is 0.38 mm to 2.28 mm, specifically, 0.38 mm, 0.76 mm, 1.14 mm, 1.52 mm, 1.9 mm, or 2.28 mm. Preferably, the thickness of the intermediate adhesive layer 12 is 0.76 mm. Optionally, the visible light transmittance of the intermediate adhesive layer 12 is greater than or equal to 85%, specifically, 85%, 90%, or 95%. Optionally, the haze of the intermediate adhesive layer 12 is less than or equal to 1%, specifically, 1%, 0.8%, 0.6%, or 0.4%. Optionally, the material of the thermoplastic polymer film can be selected from at least one of polyvinyl butyral (PVB), polyurethane (PU), ethylene-vinyl acetate copolymer (EVA), and ionic polymer (SGP). Colored thermoplastic polymer films can be selected from gray, green, or blue thermoplastic polymer films.

[0058] For example, the intermediate adhesive layer 12 can be a single-layer or multi-layer structure. Examples of multi-layer structures include double-layer, triple-layer, quadruple-layer, and five-layer structures. The intermediate adhesive layer 12 can also have other functions, such as providing at least one colored area as a shaded zone to reduce sunlight interference with the human eye, adding infrared absorbers to provide sun protection or heat insulation, adding ultraviolet absorbers to provide ultraviolet protection, or having at least one layer of the multi-layer structure with a higher plasticizer content to provide sound insulation.

[0059] In one embodiment, the intermediate adhesive layer 12 includes a first adhesive layer 121 and a second adhesive layer 122, and the first glass plate 11, the first adhesive layer 121, the adjustment layer 15, the second adhesive layer 122, and the second glass plate 13 are stacked sequentially.

[0060] Furthermore, the sum of the thicknesses of the first adhesive layer 121 and the second adhesive layer 122 is 0.38 mm to 2.28 mm, specifically, for example, 0.38 mm, 0.76 mm, 1.14 mm, 1.52 mm, 1.9 mm, or 2.28 mm. Preferably, the sum of the thicknesses of the first adhesive layer 121 and the second adhesive layer 122 is 0.76 mm.

[0061] Furthermore, the thickness ratio K of the first adhesive layer 121 and the second adhesive layer 122 satisfies: K = 1 ± 0.5, or = 1 ± 0.2, or = 1 ± 0.1.

[0062] Optionally, the first adhesive layer 121 and the second adhesive layer 122 are made of the same material. For example, the first adhesive layer 121 / adjusting layer 15 / second adhesive layer 122 is 0.38mm PVB / adjusting layer 15 / 0.38mm PVB. Another example is that the first adhesive layer 121 / adjusting layer 15 / second adhesive layer 122 is 0.76mm PVB / adjusting layer 15 / 0.38mm PVB. Yet another example is that the first adhesive layer 121 / adjusting layer 15 / second adhesive layer 122 is 0.38mm PVB / adjusting layer 15 / 0.76mm PVB.

[0063] The regulating layer 15 is disposed between the first adhesive layer 121 and the second adhesive layer 122, which can improve the impact resistance of the laminated glass 1 and enhance the durability of the regulating layer 15 against ultraviolet rays.

[0064] Optionally, the thickness ratio K of the first adhesive layer 121 to the second adhesive layer 122 is 1±0.5, that is, the first adhesive layer 121 and the second adhesive layer 122 are of equal or nearly equal thickness and made of the same material. This can avoid uneven deformation of the adjustment layer 15 in the high temperature and high pressure environment of the glass lamination process, which would lead to orange peel texture in the image and improve the yield of the laminated glass 1.

[0065] Optionally, the functional layer 14 has heat insulation and / or heating functions. The functional layer 14 is disposed on the second surface of the first glass plate 11. In this embodiment, by providing the functional layer 14, the laminated glass 1 has excellent heat insulation and / or heating performance, thereby improving the thermal comfort of the vehicle interior environment.

[0066] Optionally, the functional layer 14 may include at least one of a metal layer, a metal alloy layer, a transparent conductive oxide layer, or a stacked structure with different refractive indices.

[0067] In some embodiments, when the functional layer 14 includes a metal layer, the material of the metal layer may be at least one of gold (Au), silver (Ag), copper (Cu), aluminum (Al), and molybdenum (Mo). In some specific embodiments, the functional layer 14 may specifically include at least one silver metal layer, such as a functional layer 14 formed by a single silver metal layer and several dielectric layers located on both sides of the silver metal layer, or a functional layer 14 formed by two silver metal layers and several dielectric layers located on both sides of the silver metal layer and between the two silver metal layers, or a functional layer 14 formed by three silver metal layers and several dielectric layers located on both sides of the silver metal layer and between two adjacent silver metal layers, or a functional layer 14 formed by four silver metal layers and several dielectric layers located on both sides of the silver metal layer and between two adjacent silver metal layers. The metal layer can reflect infrared rays from sunlight, reducing the amount of infrared rays entering the vehicle's interior, thus achieving the heat insulation effect of functional layer 14. The metal layer can also conduct electricity, allowing functional layer 14 to be used as an electric heating element. It is understood that functional layer 14, whose main material is silver, may also include other metal layers, metal alloy layers, or transparent conductive oxide layers to improve infrared reflectivity or reduce sheet resistance. The materials of each dielectric layer can be independently selected from at least one of oxides, nitrides, or oxides of nitrides. Specific examples include oxides, nitrides, or oxides of at least one element selected from zirconium (Zr), niobium (Nb), silicon (Si), antimony (Sb), tin (Sn), zinc (Zn), indium (In), aluminum (Al), nickel (Ni), chromium (Cr), magnesium (Mg), manganese (Mn), vanadium (V), tungsten (W), hafnium (Hf), tantalum (Ta), molybdenum (Mo), gallium (Ga), yttrium (Y), bismuth (Bi), and titanium (Ti). Other suitable materials can also be used for the dielectric layer, and this application does not make specific limitations on this.

[0068] In some embodiments, when the functional layer 14 includes a metal alloy layer, the material of the metal alloy layer includes a metal alloy composed of at least one element selected from silver (Ag), copper (Cu), gold (Au), palladium (Pd), tin (Sn), zinc (Zn), lead (Pb), and nickel (Ni). In some further embodiments, the material of the metal alloy layer is further selected to be a metal alloy composed of silver, such as an alloy composed of silver and at least one element selected from gold, aluminum, copper, indium, tin, titanium, zinc, and platinum. The metal alloy layer can be used to reflect infrared rays in sunlight, reducing the amount of infrared rays entering the interior of the vehicle, thereby achieving the heat insulation effect of the functional layer 14. The metal alloy layer can also be used to conduct electricity, so that the functional layer 14 can be used as an electric heating element.

[0069] In some embodiments, when the functional layer 14 includes a transparent conductive oxide layer, the material of the transparent conductive oxide layer includes at least one of indium tin oxide, tin zinc oxide, fluorine-doped tin dioxide, aluminum-doped tin dioxide, gallium-doped tin dioxide, boron-doped tin dioxide, and antimony-doped tin oxide. The transparent conductive oxide layer can be used to reflect infrared rays in sunlight, reducing the amount of infrared rays entering the vehicle's interior, thereby achieving the heat insulation effect of the functional layer 14. The transparent conductive oxide layer can also be used to conduct electricity, thereby enabling the functional layer 14 to be used as an electric heating element.

[0070] In some embodiments, when the functional layer 14 comprises a stacked structure with different refractive indices, the stacked structure with different refractive indices comprises at least two thermoplastic resin films with a refractive index difference greater than or equal to 0.05. In some further embodiments, the stacked structure with different refractive indices may specifically be formed by stacking alternating layers of thermoplastic resin films with high and low refractive indices, for example, 2 to 200 alternating layers of thermoplastic resin films. The material of the thermoplastic resin films is selected from at least one of polyethylene, polypropylene, polylactic acid, poly(4-methylpentene-1), polyvinylidene fluoride, cyclic polyolefins, polymethyl methacrylate, polyvinyl chloride, polyvinyl alcohol, polyamide, polystyrene, polycarbonate, polyethylene terephthalate, polyethylene naphthalate, polyphenylene sulfide, or polyetherimide. The stacked structure with different refractive indices can be used to reflect infrared rays from sunlight, reducing the amount of infrared rays entering the vehicle's interior, thereby achieving the heat insulation effect of the functional layer 14.

[0071] The functional layer 14 may specifically be a coating layer. Optionally, the coating layer is selected from at least one of metal coating, metal alloy coating, or transparent conductive oxide coating.

[0072] Furthermore, the material of the metal coating is selected from at least one of gold (Au), silver (Ag), copper (Cu), or aluminum (Al).

[0073] Furthermore, the transparent conductive oxide coating is selected from at least one of indium tin oxide (ITO), fluorine-doped tin dioxide (FTO), aluminum-doped tin dioxide, gallium-doped tin dioxide, boron-doped tin dioxide, tin-zinc oxide, or antimony-doped tin oxide.

[0074] Furthermore, the functional layer 14 is selected from at least one of the following: single silver nanofunctional layer 14, double silver nanofunctional layer 14, triple silver nanofunctional layer 14, and quadruple silver nanofunctional layer 14.

[0075] In one embodiment, the total solar transmittance (TTS) of the laminated glass 1 is ≤50%.

[0076] The total solar transmittance (TTS) of the laminated glass 1 can be, for example, 50%, 45%, 40%, or 35%. Preferably, the total solar transmittance (TTS) of the laminated glass 1 is ≤45%. More preferably, the total solar transmittance (TTS) of the laminated glass 1 is ≤40%.

[0077] In related technologies, since the functional layer reflective sub-image is separated from the primary reflective image, it is necessary to limit the reflectivity of the functional layer. Typically, the visible light reflectance ratio (CR1) of the functional layer reflective sub-image relative to the primary reflective image in the image display area 10 is required to be ≤10% or even below 5%, in order to control the brightness of the functional layer reflective sub-image and reduce interference. This is because a weaker functional layer reflective sub-image has less interference with image quality, especially color cast. However, a weak functional layer reflective sub-image usually leads to a decrease in the reflectivity of the functional layer 14 and an increase in the total solar transmittance (TTS), resulting in a decrease in the vehicle's heat insulation performance.

[0078] However, in this application, by setting the first wedge and limiting the first preset range, the functional layer reflective sub-image and the reflective main image almost overlap, so the brightness requirement of the functional layer reflective sub-image can be relaxed, the visible light reflectance ratio CR1 of the functional layer reflective sub-image relative to the reflective main image of the image display area 10 is relaxed, the range of the coating system of the optional functional layer 14 is larger, the reflective light efficiency is improved, and the total solar transmittance TTS of the laminated glass 1 can also be improved, so that the vehicle has better heat insulation performance.

[0079] The adjustment layer 15 is used to convert S-polarized light into P-polarized light to reduce the brightness of the ghosting of the secondary image reflected by the glass plate, making the displayed image clearer.

[0080] The projected light can pass through the adjustment layer 15. Specifically, the adjustment layer 15 has a conversion rate of ≥85% for the S-polarized light.

[0081] The conversion efficiency of the adjustment layer 15 for S-polarized light can be exemplified by, for example, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99%. Preferably, the conversion efficiency of the adjustment layer 15 for S-polarized light is ≥90%. More preferably, the conversion efficiency of the adjustment layer 15 for S-polarized light is ≥98%. Even more preferably, the conversion efficiency of the adjustment layer 15 for S-polarized light is ≥99%.

[0082] The higher the conversion efficiency of the adjustment layer 15 for S-polarized light, the dimmer the secondary image reflected by the glass plate, making the displayed image clearer.

[0083] And / or, the thickness of the adjustment layer 15 is 2μm~200μm.

[0084] The thickness of the adjustment layer 15 can be specifically exemplified as 2μm, 5μm, 10μm, 25μm, 50μm, 75μm, 100μm, 125μm, 150μm, 175μm, or 200μm, etc.

[0085] And / or, the internal reflectivity of the adjustment layer 15 in the laminated glass 1 is ≤2%.

[0086] The internal reflectivity of the adjusting layer 15 in the laminated glass 1 can be specifically exemplified as 2%, 1.8%, 1.6%, 1.4%, 1.2%, 1%, 0.8%, 0.6%, 0.5%, 0.4%, or 0.2%, etc.

[0087] By limiting the reflectivity of the adjustment layer 15 to be low within the laminated glass 1, so that the adjustment layer 15 and the intermediate adhesive layer 12 have similar refractive indices, the ghosting caused by the adjustment layer 15 itself can be reduced, making the ghosting reflected by the adjustment layer 15 sufficiently dim, thereby reducing or even avoiding the impact on the clarity of the displayed image.

[0088] In one embodiment, the adjustment layer 15 is selected from a half-wave plate film.

[0089] When normally incident light passes through, the phase difference between the ordinary ray (o ray) and the extraordinary ray (e ray) is equal to π or an odd multiple thereof. Such a wafer is called a half-wave plate, or simply a half-wave plate or λ / 2 wave plate.

[0090] Furthermore, the half-wave plate film is selected from at least one of polyimide-based thin film half-wave plates, liquid crystal polymer thin film half-wave plates, indium tin oxide thin film half-wave plates, quartz-based flexible thin film half-wave plates, nanocomposite thin film half-wave plates, graphene-oxide composite thin film half-wave plates, and ultrathin dielectric metasurface half-wave plates.

[0091] Alternatively, the half-wave plate film may consist of N λ / M waveplates; where N×λ / M=λ / 2.

[0092] For example, when N=2 and M=4, a half-wave plate film is formed by combining two λ / 4 wave plates.

[0093] Alternatively, the half-wave plate film may contain a liquid crystal structure capable of polarization rotation.

[0094] For example, controlling the polarization rotation of the liquid crystal structure by 90° to form a half-wave plate film can also be called a 90° deflection conversion film or a generalized half-wave plate film.

[0095] Specifically, the projection device 21 is located on the side of the second glass plate 13 facing away from the intermediate adhesive layer 12. The projection light emitted by the projection device 21 is reflected once in the image display area 10 on the fourth surface of the second glass plate 13 to form reflected light RL1, which enters the human eye and forms a reflected primary image. Simultaneously, the projection light enters the interior of the laminated glass 1, is reflected on the first surface of the first glass plate 11 to form reflected light RL2, and then enters the human eye to form a glass plate reflected secondary image. Furthermore, the projection light also enters the interior of the laminated glass 1, is reflected by the functional layer 14 to form reflected light RL3, and then enters the human eye to form a functional layer reflected secondary image.

[0096] The laminated glass 1 has a first wedge shape, which is provided solely by the second glass plate 13. The first wedge shape is as follows: Figure 2 As shown in α1. The first wedge is used to adjust the displacement difference between the functional layer reflective sub-image and the reflective primary image, so that the functional layer reflective sub-image and the reflective primary image are nearly completely overlapped or at least to the point that they are indistinguishable to the naked eye, thereby reducing the blurriness and dizziness of the image observed by the human eye and making the displayed image clearer.

[0097] The first preset range is ≤1.6 arcmin. Specifically, the first preset range can be 1.5 arcmin, 1.4 arcmin, 1.3 arcmin, 1.2 arcmin, 1 arcmin, 0.8 arcmin, 0.6 arcmin, or 0.4 arcmin, etc. Preferably, the first preset range is ≤1.5 arcmin. More preferably, the first preset range is ≤1.2 arcmin.

[0098] Furthermore, the projected light also forms a glass plate reflective sub-image. At least within the image display area 10, the first glass plate 11 and / or the intermediate adhesive layer 12 have a second wedge shape. The second wedge shape is used to adjust the glass plate reflective sub-image so that the displacement difference between the glass plate reflective sub-image and the reflective main image is within a second preset range.

[0099] The laminated glass 1 has a second wedge shape, which is a wedge formed between the outer surface of the first glass plate 11 and the outer surface of the second glass plate 13, as shown in the figure. Figure 2 As shown in α2. The second wedge is used to adjust the displacement difference between the secondary image and the primary image reflected by the glass plate, so that the secondary image and the primary image reflected by the glass plate are nearly completely overlapped or at least to the point that they are indistinguishable to the naked eye, thereby reducing the blurriness and dizziness of the image observed by the human eye and making the displayed image clearer.

[0100] For example, the second wedge is provided solely by the first glass plate 11. Or, for another example, the second wedge is provided solely by the intermediate adhesive layer 12. Or, for yet another example, the second wedge is provided as a combination of the first glass plate 11 and the intermediate adhesive layer 12.

[0101] The first and second wedges work together to define the secondary reflective image of the glass plate, the secondary reflective image of the functional layer, and the primary reflective image, ensuring that these three images coincide and resulting in a clearer displayed image. The first and second wedges are described in detail below: Optionally, the wedge shape of the first glass plate 11, and / or the intermediate adhesive layer 12, and / or the second glass plate 13 is a fixed wedge shape or a variable wedge shape that changes linearly or non-linearly.

[0102] Further optionally, the wedge shape of the first glass plate 11, and / or the intermediate adhesive layer 12, and / or the second glass plate 13 varies linearly, or the wedge shape of the first glass plate 11, and / or the intermediate adhesive layer 12, and / or the second glass plate 13 varies monotonically and non-linearly.

[0103] Optionally, along the arrangement direction from the bottom edge to the top edge of the laminated glass 1, the thickness of the wedge-shaped first glass plate 11 and / or second glass plate 13 gradually increases. In other words, the bottom end of the first glass plate 11 and / or the second glass plate 13 is thinner, and the top end is thicker.

[0104] In one embodiment, the wedge angle of the first wedge is ≤0.295mrad, specifically for example, 0.295mrad, or 0.25mrad, or 0.2mrad, or 0.15mrad, or 0.1mrad, etc.

[0105] Preferably, the wedge angle of the first wedge is ≤0.2 mrad. More preferably, the wedge angle of the first wedge is ≤0.15 mrad. Even more preferably, the wedge angle of the first wedge is ≤0.12 mrad.

[0106] The wedge angles of the first and second wedges can be designed according to the HUD optical path and adjusted according to product requirements.

[0107] In another embodiment, the first glass plate 11 and / or the second glass plate 13 have wedge angles, the wedge angles of the first glass plate 11 and / or the second glass plate 13 gradually decrease, and the rate of change of the wedge angles of the first glass plate 11 and / or the second glass plate 13 is ≤0.3mrad / 100mm.

[0108] Compared to the preparation of glass plates with fixed wedge angles or glass plates with variable wedge shapes in related technologies, this application preferably has a gradually decreasing wedge angle between the first glass plate 11 and / or the second glass plate 13. This arrangement is beneficial to the production of glass plates, reduces the difficulty of preparation, and improves the product yield.

[0109] The rate of change of the wedge angle of the first glass plate 11 and / or the second glass plate 13 can be exemplified by, for example, 0.3 mrad / 100 mm, or 0.275 mrad / 100 mm, or 0.25 mrad / 100 mm, or 0.225 mrad / 100 mm, or 0.2 mrad / 100 mm, or 0.175 mrad / 100 mm, or 0.15 mrad / 100 mm, or 0.125 mrad / 100 mm, or 0.1 mrad / 100 mm, etc. Preferably, the rate of change of the wedge angle of the first glass plate 11 and / or the second glass plate 13 is ≤0.2 mrad / 100 mm.

[0110] The wedge angle variation rate of the first glass plate 11 and / or the second glass plate 13 can be designed according to the HUD optical path and adjusted according to product requirements.

[0111] In another embodiment, the first glass plate 11 and / or the second glass plate 13 have a wedge angle, and the wedge angle of the first glass plate 11 and / or the second glass plate 13 has a first local wedge angle fluctuation standard deviation σ1 within the image display area 10, the first local wedge angle fluctuation standard deviation σ1 satisfying the following condition: 3σ1≤0.08mrad / 10mm.

[0112] The method for measuring the standard deviation of local wedge angle fluctuation is as follows: along the direction of the wedge angle, the measurement points are spaced 10 mm apart, and the standard deviation of the deviation between the wedge angle of multiple measurement points and the corresponding expected design wedge angle is measured.

[0113] The first local wedge angle fluctuation standard deviation σ1 can be exemplified as follows: 3σ1≤0.08mrad / 10mm, or 3σ1≤0.07mrad / 10mm, or 3σ1≤0.06mrad / 10mm, or 3σ1≤0.05mrad / 10mm, or 3σ1≤0.04mrad / 10mm, or 3σ1≤0.03mrad / 10mm, or 3σ1≤0.02mrad / 10mm, or 3σ1≤0.01mrad / 10mm, etc.

[0114] Preferably, the standard deviation σ1 of the first local wedge angle fluctuation satisfies the following condition: 3σ1≤0.05mrad / 10mm. More preferably, the standard deviation σ1 of the first local wedge angle fluctuation satisfies the following condition: 3σ1≤0.03mrad / 10mm.

[0115] Therefore, this embodiment limits the standard deviation σ1 of the first local wedge angle fluctuation to select a glass plate with smaller local wedge angle fluctuation. The smaller the local wedge angle fluctuation, the better the superposition stability of the ghost image and the main image.

[0116] And / or, the intermediate adhesive layer 12 has a wedge angle, the wedge angle of the intermediate adhesive layer 12 having a second local wedge angle fluctuation standard deviation σ2 within the image display area 10, the second local wedge angle fluctuation standard deviation σ2 satisfying the following condition: 3σ2≤0.15mrad / 10mm.

[0117] The second local wedge angle fluctuation standard deviation σ2 can be exemplified by 3σ2≤0.15mrad / 10mm, or 3σ2≤0.14mrad / 10mm, or 3σ2≤0.13mrad / 10mm, or 3σ2≤0.12mrad / 10mm, or 3σ2≤0.11mrad / 10mm, or 3σ2≤0.1mrad / 10mm, or 3σ2≤0.09mrad / 10mm, or 3σ2≤0.08mrad / 10mm, or 3σ2≤0.07mrad / 10mm, or 3σ2≤0.06mrad / 10mm, or 3σ2≤0.05mrad / 10mm, etc.

[0118] Preferably, the standard deviation σ2 of the second local wedge angle fluctuation satisfies the following condition: 3σ2 ≤ 0.12 mrad / 10 mm. More preferably, the standard deviation σ2 of the second local wedge angle fluctuation satisfies the following condition: 3σ2 ≤ 0.1 mrad / 10 mm.

[0119] Therefore, this embodiment selects an intermediate adhesive layer 12 with smaller local wedge angle fluctuations by limiting the second local wedge angle fluctuation standard deviation σ2. The smaller the local wedge angle fluctuation, the better the superposition stability of the ghost image and the main image.

[0120] In yet another embodiment, the first glass plate 11 and / or the second glass plate 13, which are wedge-shaped, have a spray direction, which is either vertical or horizontal. Preferably, the spray direction is vertical.

[0121] The direction of the molten glass runner refers to the direction in which the molten glass moves across the surface of the molten tin during the float glass production process. This embodiment, by limiting the molten glass runner direction to vertical or horizontal, can reduce driver visual distortion and fatigue, lessen the blurriness and dizziness experienced when viewing images, thereby improving driver comfort and safety.

[0122] In summary, the laminated glass 1 provided in this embodiment, by setting a first wedge shape and defining a first preset range, makes the reflected primary image and the reflected secondary image of the functional layer coincide, resulting in a clear displayed image. Furthermore, since the functional layer 14 has a reflective property, it can also enhance brightness. Moreover, because the reflected primary image and the reflected secondary image of the functional layer have a high degree of overlap, it is easy to adjust the projection device 21 to achieve color correction of the superimposed image, making the displayed image better free of color deviation. In addition, the adjustment layer 15 significantly weakens the brightness of the reflected secondary image of the glass plate, and even eliminates the ghosting of the reflected secondary image of the glass plate, avoiding image blurring caused by insufficient overlap accuracy between the reflected secondary image and the reflected primary image of the glass plate. Thus, a clear displayed image can be observed, improving driving safety.

[0123] On the one hand, this embodiment sets a first wedge to reduce the ghosting between the functional layer's reflective sub-image and the reflective main image. On the other hand, the adjustment layer 15 is used to weaken the ghosting brightness of the glass plate's reflective sub-image. The two are systemic collaborations and need to be considered from an overall perspective: combining the human eye's requirements for the image, the optimal position of the functional layer 14, the optimal superposition method of reflective images from different interfaces, the causes of color cast in the functional layer's reflective sub-image and the optimal adjustment method, the actual manufacturing tolerances of the sheet and the problems they cause, the production process of the wedge-shaped original sheet, glass forming technology, HUD optical path specifications, product cost and yield, product experience, and the interrelationships between these aspects, considering the overall HUD system, thus obtaining the technical solution provided by this embodiment.

[0124] In another embodiment, the vertical field of view (VFOV) of the image display area 10 is ≤7°.

[0125] The vertical field of view (VFOV) of the image display area 10 refers to the maximum angular range that the projection system can present virtual images in the vertical direction.

[0126] The vertical field of view (VFOV) can be specifically exemplified as 7°, 6°, 5°, 4°, 3°, 2°, or 1°, etc. Preferably, the VFOV of the image display area 10 is ≤5°. More preferably, the VFOV of the image display area 10 is ≤4°.

[0127] The large-format HUD image corresponds to a large vertical field of view (VFOV). This embodiment, by setting a first wedge and limiting a first preset range, enables a high degree of overlap between the reflected main image and the reflected secondary image of the functional layer, while also achieving a larger vertical field of view (VFOV) to obtain a clear large-format HUD image.

[0128] In another embodiment, the laminated glass 1 has a reflection spectrum for the projected light, wherein the difference between the maximum and minimum reflectance values ​​in the 450nm~630nm wavelength band is PV≤6%.

[0129] The difference PV between the maximum and minimum reflectance values ​​in the 450nm~630nm wavelength range of the reflectance spectrum can be exemplified by 6%, 5%, 4%, 3%, 2%, or 1%, etc. Preferably, the difference PV between the maximum and minimum reflectance values ​​in the 450nm~630nm wavelength range of the reflectance spectrum is ≤3%. More preferably, the difference PV between the maximum and minimum reflectance values ​​in the 450nm~630nm wavelength range of the reflectance spectrum is ≤2%.

[0130] Therefore, this embodiment minimizes the difference PV between the maximum and minimum reflectance values ​​to keep the reflectance spectrum curve flat or nearly flat in the 450nm~630nm band. This reduces or eliminates RGB color shift in the overlapping image of the functional layer's reflective sub-image and reflective primary image, thereby reducing the need for light source color adjustment in the projection device 21 and making it easier for the human eye to observe a recognizable display image, or even a clear display image, thus further improving driving safety.

[0131] In yet another embodiment, the visible light reflectance ratio CR1 of the functional layer reflective sub-image of the image display area 10 relative to the reflective primary image is ≥8%.

[0132] The visible light reflectance CR1 of the functional layer reflective sub-image of the image display area 10 relative to the reflective main image can be exemplified as 8%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, or 50%, etc. Preferably, the visible light reflectance CR1 of the functional layer reflective sub-image of the image display area 10 relative to the reflective main image is ≥10%. More preferably, the visible light reflectance CR1 of the functional layer reflective sub-image of the image display area 10 relative to the reflective main image is ≥15%.

[0133] This embodiment sets a first wedge and defines a first preset range so that the reflective primary image and the functional layer reflective secondary image coincide. Therefore, the visible light reflectance ratio CR1 of the functional layer reflective secondary image relative to the reflective primary image of the image display area 10 can be relatively relaxed, and a clear display image can also be obtained.

[0134] Please refer to Figure 3 The visible light reflectance CR1 of the functional layer reflective sub-image relative to the reflective primary image can be calculated using the anti-reflection prism coupling measurement method, or simply the prism coupling method. The prism coupling method is described in detail below: First, a detection device 3 is provided, which includes two optical prisms with isosceles symmetry: a first optical prism 311 and a second optical prism 312, an optical coupling agent, and three anti-reflection optical elements: a first anti-reflection optical element 321, a second anti-reflection optical element 322, and a third anti-reflection optical element 323.

[0135] A first optical prism 311 is placed on the first surface of the laminated glass 1, and a second optical prism 312 is placed on the fourth surface of the laminated glass 1. An optical coupling agent is disposed at the connection between the optical prisms and the laminated glass 1. A first anti-reflection optical element 321 is placed on the surface of the first optical prism 311 facing away from the laminated glass 1. A second anti-reflection optical element 322 and a third anti-reflection optical element 323 are placed on the surface of the second optical prism 312 facing away from the laminated glass 1. Furthermore, the second anti-reflection optical element 322 and the third anti-reflection optical element 323 are symmetrically arranged, and the second anti-reflection optical element 322 is symmetrically arranged with the first anti-reflection optical element 321. After the laminated glass 1 is combined with the detection device 3, an optical prism coupling structure is obtained.

[0136] like Figure 3 As shown, during the detection, the incident light is labeled T0, and the sample is labeled S. The incident light T0 enters the sample S and is reflected to form reflected light R1, and the incident light T0 passes through the sample S to form transmitted light T1.

[0137] Specifically, incident light T0 enters through the third anti-reflection optical element 323 with an incident angle of 0°, which is the angle between the incident light T0 and the normal to the incident interface. Reflected light R1 exits through the second anti-reflection optical element 322 with an exit angle of 0°, which is the angle between the reflected light R1 and the normal to the exit interface. Transmitted light T1 exits through the first anti-reflection optical element 321 with an exit angle of 0°, which is the angle between the transmitted light T1 and the normal to the exit interface.

[0138] The specific steps of the detection method are as follows: S10. Select an optical prism of appropriate specifications according to the test incident angle. The relationship between the incident angle β of the laminated glass 1 (air surface to glass interface) and the incident angle γ in the optical prism structure is γ=asin(sinβ / n), where n is the refractive index of the laminated glass 1. For example, if the incident angle of the laminated glass 1 is β=66°, then the incident angle γ in the optical prism structure is 37°.

[0139] S20 involves directly connecting and filling two optical prisms with an optical coupling agent to obtain a control coupling structure. Visual testing shows that the optical path is transparent, without ghosting, bubbles, or contamination.

[0140] S30, place the entire control coupling structure into the spectrophotometer, and then measure the transmission spectrum. The measurement interval is 5 nm.

[0141] S40, remove the control coupling structure, then clamp the laminated glass sample 1 according to the actual incident direction and re-connect and fill it with optical coupling agent to obtain a reassembled optical prism coupling structure. Visually test the optical path to ensure it is transparent, without ghosting, bubbles, or contaminants. Then, place the entire optical prism coupling structure into a spectrophotometer and measure the reflectance spectrum. The measurement interval is 5 nm.

[0142] S50, Spectral data processing, calculation of internal reflection spectrum: .

[0143] Internal reflectance of functional layer 14 at a specific incident angle β: ; where RL can be further subdivided into RLp and RLs according to the incident P / S polarized light. This is the relative value of the product of the HUD light source's relative spectral power distribution function and the CIE spectral luminous efficacy. The product is normalized to 100%.

[0144] Spectral reflectance ratio of the secondary image of the functional layer 1 of the laminated glass: ;in, This is the reflectance ratio of the primary image measured by a spectrophotometer; for ordinary glass, it can be calculated using the Fresnel formula.

[0145] Visible light reflectance of the functional layer secondary image relative to the primary image: ; where RL ghost RL is the visible light reflectance of the functional layer sub-image under HUD light source conditions (usually S- or P-polarized light). primary It is the visible light reflectance of the reflected main image under HUD light source conditions (usually divided into S or P polarized light).

[0146] In some embodiments, the visible light reflectance of the functional layer secondary image relative to the primary image can be determined according to ISO / CIE 11664-4 / CIE 1976 Lab standards, using the brightness value L of the primary image. * primary and the brightness value L of the functional layer reflective sub-image * ghost Perform the conversion.

[0147] Optionally, the visible light reflectance CR2 of the glass plate reflecting sub-image of the image display area 10 relative to the reflecting primary image is ≤10%.

[0148] The visible light reflectance CR2 of the glass plate secondary image of the image display area 10 relative to the primary image can be, for example, 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, or 4%. Preferably, the visible light reflectance CR2 of the glass plate secondary image of the image display area 10 relative to the primary image is ≤5%. More preferably, the visible light reflectance CR2 of the glass plate secondary image of the image display area 10 relative to the primary image is ≤3%.

[0149] This embodiment reduces the brightness of the glass plate reflective sub-image by limiting the visible light reflectance ratio CR2 of the glass plate reflective sub-image relative to the reflective primary image in the image display area 10, thereby obtaining a clear display image.

[0150] Especially suitable for situations where the incident angle AOI of light exceeds the Brewster angle θ B The larger the reflective sub-image of the glass plate, the brighter it becomes. By adopting the structure of this application and combining it with the visible light reflectance ratio CR2 of the glass plate reflective sub-image relative to the reflective main image in the image display area 10, a clearer display image can be observed.

[0151] In yet another embodiment, the chroma C of the functional layer reflective sub-image * ab ≤40.

[0152] Among them, chroma C * ab This can be obtained by referring to CIELAB standards and GB / T 21047.

[0153] Chroma C of functional layer reflective subimage * ab Specific examples include 40, 35, 30, 25, 20, 15, 10, or 5, etc. Preferably, according to the CIE 1976 standard, the chroma C of the functional layer reflective sub-image... * ab ≤25. More preferably, according to the CIE 1976 standard, the chroma C of the functional layer reflective subimage is... * ab ≤15.

[0154] Chroma C * ab The smaller the value, the closer the functional layer reflective subimage is to neutral colors, and the smaller its impact on image color cast. Therefore, this embodiment limits the chroma C of the functional layer reflective subimage. * ab ≤40, so that the functional layer reflective sub-image is closer to the neutral color, reducing the influence of the functional layer reflective sub-image on the color deviation of the displayed image, and reducing the difficulty of color correction of the projection device 21.

[0155] In yet another embodiment, the incident angle β of the projected light satisfies the following condition: 45°<β≤70°.

[0156] The incident angle β of the projected light can be exemplified by 46°, 48°, 50°, 52°, 54°, 56°, 58°, 60°, 62°, 64°, 66°, 68°, or 70°, etc.

[0157] The incident angle β of the projected light is based on the principal ray of the central eyebox.

[0158] This implementation limits the incident angle β of the projected light rays to be as close as possible to the Brewster angle θ. B (Ordinary glass has an angle of about 57°), which further reduces the brightness of the secondary image reflected by the glass plate, so as to make the displayed image clearer.

[0159] This application also provides a projection system, which includes a projection device and a laminated glass as described above. The projection device is disposed on the side of the second glass plate away from the intermediate adhesive layer. The projection device is used to generate projection light, which includes S-polarized light. The proportion of S-polarized light in the projection light is ≥75%. The image display area is used to receive and reflect the projection light to form a reflected main image.

[0160] Optionally, the wavelength of the projected light includes 380nm to 780nm.

[0161] This application also provides a vehicle, the vehicle including a body and a laminated glass as described above, the laminated glass being disposed on the body.

[0162] The projection device of the projection system can be installed inside the vehicle body, while the laminated glass is installed at the opening in the vehicle body.

[0163] When laminated glass is installed in a vehicle, it is preferably used as the windshield. However, it is not limited to this; laminated glass can also be used as the rear windshield or side window, thus providing more display applications for the vehicle. In addition to vehicles, laminated glass can also be used in transportation vehicles such as airplanes, trains, and rail transit.

[0164] The projection system and vehicle provided in this application utilize the laminated glass provided in this application. By setting a first wedge shape and defining a first preset range, the laminated glass ensures that the reflected primary image and the reflected secondary image of the functional layer coincide, resulting in a clear displayed image. Furthermore, due to the reflectivity of the functional layer, brightness enhancement is achieved. Moreover, the high degree of overlap between the reflected primary image and the reflected secondary image of the functional layer facilitates adjustment of the projection device to achieve color correction of the superimposed image, resulting in a better color-shift-free displayed image. Additionally, the use of an adjustment layer significantly weakens the brightness of the reflected secondary image of the glass plate, and even eliminates the ghosting of the reflected secondary image of the glass plate, avoiding image blurring caused by insufficient overlap accuracy between the reflected secondary image and the reflected primary image of the glass plate. This enables the observation of a clear displayed image and improves driving safety.

[0165] To make the objectives and advantages of this application clearer, the effects of the laminated glass of this application will be further explained in detail below with reference to specific embodiments.

[0166] Comparative Example 1: Glass plate 2.1mm / wedge-shaped PVB intermediate adhesive layer 0.76mm / triple silver coating 3A1 / glass plate 2.1mm; Comparative Example 2: Glass plate 2.1mm / wedge-shaped PVB intermediate adhesive layer 0.76mm / triple silver coating 3A2 / glass plate 2.1mm; Comparative Example 3: Glass plate 2.1mm / wedge-shaped PVB intermediate adhesive layer 0.76mm / four silver coating 4A1 / glass plate 2.1mm; Example 1: 2.1mm glass plate / 0.38mm PVB intermediate adhesive layer / 0.1mm adjustment layer / 0.38mm PVB intermediate adhesive layer / 3A1 triple silver coating / 2.1mm wedge-shaped glass plate; Example 2: 2.1mm glass plate / 0.38mm PVB intermediate adhesive layer / 0.1mm adjustment layer / 0.38mm PVB intermediate adhesive layer / 3A2 triple silver coating / 2.1mm wedge-shaped glass plate; Example 3: 2.1mm glass plate / 0.38mm PVB intermediate adhesive layer / 0.1mm adjustment layer / 0.38mm PVB intermediate adhesive layer / 4A1 four-silver coating / 2.1mm wedge-shaped glass plate; Example 4: 2.1mm glass plate / 0.38mm wedge-shaped PVB intermediate adhesive layer / 0.1mm adjusting layer / 0.38mm PVB intermediate adhesive layer / 3A1 triple silver coating / 2.1mm wedge-shaped glass plate; Example 5: 2.1mm glass plate / 0.38mm wedge-shaped PVB intermediate adhesive layer / 0.1mm adjusting layer / 0.38mm PVB intermediate adhesive layer / 3A2 triple silver coating / 2.1mm wedge-shaped glass plate; Example 6: 2.1mm glass plate / 0.38mm wedge-shaped PVB intermediate adhesive layer / 0.1mm adjusting layer / 0.38mm PVB intermediate adhesive layer / 4A1 silver coating / 2.1mm wedge-shaped glass plate; Among them, the three-silver 3A1 / four-silver 4A1 is a high heat insulation coating. Examples 1-3 are provided with a first wedge, and Examples 4-6 are provided with a first wedge and a second wedge.

[0167] The HUD parameters are as follows: The eye box includes an upper eye box, a middle eye box, and a lower eye box. Each eye box measures 130×45mm, and the vertical spacing between each eye box is 40mm. The field of view (HFOV) is 9.0°, the virtual field of view (VFOV) is 7.0°, the virtual image distance is 2500mm, the angle of incidence (AOI) of the principal optical axis of the middle eye box at the inner surface of the glass is 63.4°, the projection light source is S-polarized light, and the conversion efficiency of the half-wave plate (HWP) to S-polarized light is ψ=95%.

[0168] First, the ghosting amount of the functional layer reflective sub-image in the laminated glass, i.e., the deviation between the functional layer reflective sub-image and the reflective primary image, is simulated. The data are shown in Tables 1 and 2 below. For the comparative example, the glass plate has no wedge shape, which can be understood as a wedge angle of 0 mrad; for the embodiment, the glass plate has a wedge shape, and through simulation, a fixed wedge angle of 0.20 mrad can be obtained where the ghosting of each eyepiece coating is minimal.

[0169] Table 1: Ghosting parameters of the functional layer reflection sub-image in the comparative example of laminated glass

[0170] Table 2: Ghosting parameters of the functional layer reflection sub-image of the laminated glass in the embodiments

[0171] In the simulation, the distribution of the reflective sub-images of each functional layer of the virtual image corresponding to the coordinates of the central eye point of the mid-eyebox is shown in Tables 3 and 4. The units of the data in Tables 3 and 4 are arcmin.

[0172] Table 3: Simulation ghosting parameters of the functional layer reflection sub-images of laminated glass in Comparative Examples 1-3

[0173] Table 4: Simulation ghosting parameters of the functional layer reflection sub-images of laminated glass in Examples 1-6

[0174] Among them, ghosting is divided into total ghosting and component ghosting in specific directions, usually in the horizontal and vertical directions. The data in Tables 3 and 4 are total ghosting.

[0175] According to Tables 1-2, the glass plates in Comparative Examples 1-3 are ordinary glass, and the ghosting corresponding to the upper, middle, and lower eyelids is significantly larger, with an average value of 2.85 arcmin and a maximum of 3.06 arcmin. Obviously, the functional layer reflection sub-image is visible to the human eye. In contrast, the glass plates in Examples 1-6 are wedge-shaped, and the functional layer reflection sub-images corresponding to the upper, middle, and lower eyelids are significantly smaller, with an average absolute value of 0.69 arcmin and a maximum of 1.04 arcmin. The functional layer reflection sub-image is not visible to the human eye.

[0176] In addition, the vertical field of view (VFOV) in this HUD case is set to be much higher than usual, reaching 7°. At this time, the ghosting of each eye box is less than 1.5 arcmin, which shows that the VFOV can have a larger range. Considering that the thickness of the second glass plate can be reduced, the VFOV range can be further expanded, for example, to 8°, 9°, 10°, etc.

[0177] As shown in Tables 3-4, in the comparative example, the distribution of the functional layer reflective sub-images corresponding to the virtual image at the center eye point of the eye box is approximately uniform, with a data range of 0.4 arcmin. The ghosting of virtual images at each position is large, meaning that it is difficult to improve the size of the ghosting even by reducing the VFOV. In the embodiment, the distribution of the functional layer reflective sub-images is approximately uniform, and the ghosting of each virtual image is small, which means that the VFOV has greater design space.

[0178] Considering that local wedge angle fluctuations in the HUD area can lead to increased ghosting, for a specific HUD optical path, the ghosting variation rate M at a specific eye point and virtual image position is M = (ghosting amount 1 - ghosting amount 2) / (wedge angle 1 - wedge angle 2). Based on this, the maximum ghosting variation rate Mtall = 16.38 arcmin / mrad in the upper eye box can be calculated, and the upper tolerance of the wedge fluctuation = current wedge angle + upper ghosting margin / ghosting variation rate = 0.20 + (1.6 - 1.04) / 16.38 = 0.234 mrad; the maximum ghosting variation rate Mlow = 10.31 arcmin / mrad in the lower eye box, and the lower tolerance of the wedge fluctuation = current wedge angle - lower ghosting margin / ghosting variation rate = 0.20 - (1.6 - 0.989) / 10.31 = 0.141 mrad; thus, the half-bandwidth of the wedge fluctuation tolerance is ±0.047 mrad. The target of 1.6 arcmin can be met under this tolerance.

[0179] This case study demonstrates a large VFOV, thicker glass, and a shorter virtual image distance. To optimize ghosting, possible measures include: reducing glass thickness to decrease the VFOV range; improving local wedge angle fluctuations; and optimizing the HUD optical path design, such as increasing the virtual image distance (VID), decreasing the projection ray incident angle, and reducing the eyebox size. Similarly, parameters can be adjusted to expand the local wedge angle fluctuation range, thereby reducing production costs.

[0180] Then, the brightness ratio of the functional layer's reflective sub-image to the reflective primary image was obtained and calculated using the optical prism coupling method. The data is summarized in Table 5; the HUD light source is as follows. Figure 4 As shown, light source A is a TFT-LCD, and light source B is an LCoS.

[0181] Next, the imaging performance of the HUD sample was visually evaluated and recorded in Table 5. The HUD optical path was projected with a white patterned light source. On the actual vehicle simulation test bench, the image brightness was adjusted, and the color state of the ghost image reflected by the functional layer of the HUD image was visually observed and photographed.

[0182] Table 5: Evaluation index parameters for the functional layer reflection sub-images of laminated glass in Comparative Examples 1-3

[0183] Table 6: Evaluation index parameters of the functional layer reflection sub-image of laminated glass in Examples 1-3

[0184] Table 7: Evaluation index parameters of the functional layer reflection sub-image of laminated glass in Examples 4-6

[0185] As shown in Tables 5-7 above, for the ghosting value of the glass plate's secondary image and the primary image, if the wedge angle of the laminated glass is set to 0.47 mrad according to the relevant technology, so that the glass plate's secondary image and the primary image coincide, then the conventional ghosting corresponding to the three eye boxes is too large when the VFOV is large. Obviously, reducing the VFOV can reduce the amount of ghosting. However, considering the local wedge shape accuracy of the actual product, the ghosting of the glass plate's secondary image and the primary image will increase significantly, while the ghosting of the functional layer's secondary image and the primary image will only increase slightly.

[0186] Regarding the brightness ratio of the functional layer reflective sub-image to the primary reflective image and the brightness ratio of the glass plate reflective sub-image to the primary reflective image, under the relevant technology, the functional layer reflective sub-images in Comparative Examples 1 and 3 have high brightness, appearing distinctly red, and are separated from the primary reflective image. Therefore, the functional layer reflective sub-images are clearly visible, resulting in a blurry and reddish image. In contrast, the functional layer reflective sub-images in Examples 1 and 3 are not separated from the primary reflective image and appear red before color adjustment. After the HUD optical engine completes white balance color adjustment, the overlapping image can be made close to white, resulting in a clearer image and significantly improving the image color cast problem. At this time, the glass plate reflective sub-image is separated from the primary reflective image, and the glass plate reflective sub-image is significantly weakened. For example, in Comparative Example 1 + Light Source A, the brightness ratio of the glass plate reflective sub-image to the primary reflective image decreases from 33.9% to 2.7%; in Comparative Example 3 + Light Source A, the brightness ratio of the glass plate reflective sub-image to the primary reflective image decreases from 28.1% to 2.2%, appearing slightly pale green. In high-contrast scenes, such as dim nighttime, it is slightly visible in local areas, which can be used in most scenarios. Furthermore, according to Examples 4 and 6, a wedge shape is used to achieve overlap of the three images, and after color white balance adjustment, the image is close to white and clearer. However, in related technologies, Comparative Examples 1 and 3 are almost unusable, while in this technology, Examples 1-6 are usable and have good results.

[0187] Furthermore, regarding Comparative Example 2, Example 2, and Example 4, Comparative Example 2 is basically usable, but the brightness of the glass plate reflective sub-image is high and it cannot be well superimposed with the reflective main image, resulting in uneven ghosting and a large maximum total ghosting, which is not good enough. This application, through the superposition of multiple technical advantages, not only achieves a significant reduction in the brightness of the glass plate reflective sub-image in Examples 2 and 4, for example, in Comparative Example 1 + light source A, the brightness ratio of the glass plate reflective sub-image to the reflective main image is reduced from 42.0% to 3.3%, with less color adjustment and easier processing. In particular, Example 4 also achieves basic superposition of the three images at the same time, resulting in a better HUD image effect.

[0188] Meanwhile, in this application, the functional layer's reflective sub-image and reflective primary image overlap well. Even if the functional layer's reflective sub-image has a certain degree of color cast, it can be corrected at the HUD light source end. Therefore, the correlation between the functional layer's thermal insulation performance and the HUD imaging performance decreases. The range of selectable film systems for the functional layer increases, and lower thermal insulation performance can be achieved. In this case, the total energy transmittance (TTS) of Triple Silver 3A1 / Triple Silver 3A2 / Quadruple Silver 4A1 are 40.5%, 42.1%, and 38.6%, respectively, and the visible light transmittance (TL) is >70%.

[0189] The total energy transmittance (TTS) was measured using the standard ISO 13837.

[0190] Unless otherwise stated or in case of conflict, the terms or phrases used in this application shall have the following meanings: In this application, terms such as "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature.

[0191] In this application, "one or more" refers to any one, any two, or any two or more of the listed items. "Several" refers to any two or more.

[0192] In this application, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0193] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part. They can refer to a mechanical connection or an electrical connection. They can refer to a direct connection or an indirect connection through an intermediate medium, or the internal communication of two components or the interaction between two components. For those skilled in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances.

[0194] In this application, the terms "embodiment" and "implementation" mean that a specific feature, structure, or characteristic described in connection with an embodiment can be included in at least one embodiment of this application. The appearance of these phrases in various locations throughout the specification does not necessarily refer to the same embodiment, nor are they independent or alternative embodiments mutually exclusive with other embodiments. Those skilled in the art will understand, explicitly and implicitly, that the embodiments described in this application can be combined with other embodiments. Furthermore, it should be understood that the features, structures, or characteristics described in the various embodiments of this application can be arbitrarily combined to form yet another embodiment that does not depart from the spirit and scope of the technical solution of this application, provided there is no contradiction between them.

[0195] The above description represents some embodiments of this application. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of this application, and these improvements and modifications are also considered to be within the scope of protection of this application.

Claims

1. A laminated glass, characterized in that, The laminated glass includes a first glass plate, an intermediate adhesive layer, and a second glass plate stacked sequentially. The laminated glass also includes a functional layer disposed between the intermediate adhesive layer and the second glass plate. The first glass plate includes a first surface facing away from the intermediate adhesive layer and a second surface close to the intermediate adhesive layer; the second glass plate includes a third surface close to the intermediate adhesive layer and a fourth surface facing away from the intermediate adhesive layer. The laminated glass has an image display area for receiving and reflecting projected light to form a primary image, and the projected light also forms a secondary image of the functional layer. At least within the area of ​​the image display area, the second glass plate has a first wedge shape for adjusting the secondary image of the functional layer so that the displacement difference between the secondary image of the functional layer and the primary image of the reflection is within a first preset range, the first preset range being ≤1.6 arcmin. The laminated glass also includes an adjustment layer located in the image display area. The adjustment layer is disposed between the first glass plate and the functional layer, and is used to convert S-polarized light into P-polarized light.

2. The laminated glass as described in claim 1, characterized in that, The wedge angle of the first wedge is ≤0.295mrad.

3. The laminated glass as described in claim 1, characterized in that, The projected light also forms a glass plate reflective sub-image. At least within the image display area, the first glass plate and / or the intermediate adhesive layer have a second wedge shape. The second wedge shape is used to adjust the glass plate reflective sub-image so that the displacement difference between the glass plate reflective sub-image and the reflective main image is within a second preset range.

4. The laminated glass as described in claim 1, characterized in that, The first glass plate and / or the second glass plate have a wedge angle, and the wedge angle of the first glass plate and / or the second glass plate has a first local wedge angle fluctuation standard deviation σ1 within the image display area. The first local wedge angle fluctuation standard deviation σ1 satisfies the following condition: 3σ1≤0.08mrad / 10mm.

5. The laminated glass as described in claim 1, characterized in that, The intermediate adhesive layer has a wedge angle, and the wedge angle of the intermediate adhesive layer has a second local wedge angle fluctuation standard deviation σ2 within the image display area. The second local wedge angle fluctuation standard deviation σ2 satisfies the following condition: 3σ2≤0.15mrad / 10mm.

6. The laminated glass as described in claim 1, characterized in that, The first glass plate and / or the second glass plate with a wedge angle have a spray direction, which is vertical or horizontal.

7. The laminated glass as described in claim 1, characterized in that, The vertical field of view (VFOV) of the image display area is ≤7°.

8. The laminated glass as described in claim 1, characterized in that, The conversion efficiency of the adjustment layer for the S-polarized light is ≥85%; And / or, the thickness of the adjustment layer is 2μm~200μm; And / or, the internal reflectivity of the adjustment layer in the laminated glass is ≤2%.

9. The laminated glass as described in claim 1, characterized in that, The adjustment layer is selected from half-wave plate films.

10. The laminated glass as described in claim 9, characterized in that, The half-wave plate film is selected from at least one of polyimide-based thin film half-wave plates, liquid crystal polymer thin film half-wave plates, indium tin oxide thin film half-wave plates, quartz-based flexible thin film half-wave plates, nanocomposite thin film half-wave plates, graphene-oxide composite thin film half-wave plates, and ultrathin dielectric metasurface half-wave plates.

11. The laminated glass as claimed in claim 1, characterized in that, The intermediate adhesive layer includes a first adhesive layer and a second adhesive layer, and the first glass plate, the first adhesive layer, the adjustment layer, the second adhesive layer, and the second glass plate are stacked in sequence.

12. The laminated glass as claimed in claim 11, characterized in that, The sum of the thicknesses of the first adhesive layer and the second adhesive layer is 0.38 mm to 2.28 mm; And / or, the thickness ratio K of the first adhesive layer to the second adhesive layer satisfies: K=1±0.

5.

13. The laminated glass as claimed in claim 1, characterized in that, The laminated glass has a reflection spectrum for the projected light, wherein the difference between the maximum and minimum reflectance values ​​in the 450nm~630nm wavelength band is PV≤6%.

14. The laminated glass as claimed in claim 1, characterized in that, The visible light reflectance ratio CR1 of the functional layer reflective sub-image of the image display area relative to the reflective primary image is ≥8%.

15. The laminated glass as claimed in claim 1, characterized in that, The visible light reflectance ratio (CR2) of the glass plate reflecting the secondary image in the image display area relative to the primary image is ≤10%.

16. The laminated glass as claimed in claim 1, characterized in that, The chroma C of the functional layer reflective subimage * ab ≤40.

17. The laminated glass as claimed in claim 1, characterized in that, The incident angle β of the projected light satisfies the following condition: 45°<β≤70°.

18. The laminated glass as claimed in claim 1, characterized in that, The thickness of the second glass plate is ≤2.1mm; And / or, at least within the area of ​​the image display region, a coloring material is provided between the first surface and the functional layer, the coloring material having a visible light transmittance of ≥50%, ≥60%, or ≥70%; And / or, the total solar transmittance (TTS) of the laminated glass is ≤50%.

19. A projection system, characterized in that, The projection system includes a projection device and a laminated glass as described in any one of claims 1-18. The projection device is disposed on the side of the second glass plate away from the intermediate adhesive layer. The projection device is used to generate projection light, the projection light includes S-polarized light, and the proportion of S-polarized light in the projection light is ≥75%. The image display area is used to receive and reflect the projection light to form a reflected main image.

20. A vehicle, characterized in that, The vehicle includes a body and a laminated glass as described in any one of claims 1-18, the laminated glass being disposed on the body.

Images