Laminated glass, projection system and vehicle

Abstract

The invention provides laminated glass, a projection system and a vehicle. The interlayer of the laminated glass includes an in-coupling region and an out-coupling region. The projection light can enter the coupling-in area from the fourth surface, and the projection light can be reflected between the middle layer and the fourth surface in a reciprocating manner after being reflected by the coupling-in area, so that the projection light is propagated in the second glass plate; moreover, projection light propagating in the second glass plate can be emitted to the coupling-out area, and the projection light can penetrate through the fourth face after being reflected by the coupling-out area so as to be emitted out of the second glass plate. The refractive index of the polymer layer is smaller than that of the second glass plate, and the refractive index of air is smaller than that of the second glass plate, so that the second glass plate forms an optical waveguide structure, projection light can be transmitted in the second glass plate, and the coupling-in area and the coupling-out area are arranged in a matched mode. The projection light is totally reflected in the second glass plate, so that the ghosting phenomenon is reduced or even eliminated, and the display effect of the laminated glass is improved.

Description

Technical Field

[0001] The present application belongs to the field of glass technology, and specifically relates to laminated glass, a projection system and a vehicle. Background Art

[0002] In vehicles, head-up display (HUD) technology can use optical projection to directly display an image containing driving information in front of the glass, eliminating the need for users to lower their heads to observe the dashboard while driving, greatly improving driving convenience and safety.

[0003] Traditional head-up display technology directly uses laminated glass as a reflective surface, and the projected light enters the user's eyes after a single reflection through the laminated glass. Since laminated glass is composed of an outer glass plate, an intermediate layer, and an inner glass plate, its structure determines that the direct projection reflection technology will inevitably cause secondary reflections at the interface between the outer glass plate, the intermediate layer, the inner glass plate, and the air in addition to the main reflective surface (the fourth surface). The image formed by the secondary reflection is called a "ghost image", which generally overlaps with the main image, causing the actual image observed by the user to appear blurred due to the overlap of the main image and the "ghost image", affecting the display effect of the laminated glass and reducing the user experience. Summary of the invention

[0004] In view of this, a first aspect of the present application provides a laminated glass, comprising a first glass plate, an intermediate layer, and a second glass plate, wherein the first glass plate has a first surface and a second surface, the second glass plate has a third surface and a fourth surface, and the intermediate layer connects the second surface and the third surface;

[0005] The refractive index of the intermediate layer is smaller than the refractive index of the second glass plate, and the intermediate layer includes an incoupling region and an outcoupling region which are spaced apart, the incoupling region is used to receive the projection light incident from the fourth surface and change the propagation direction of the projection light, and the outcoupling region is used to receive the projection light propagating in the second glass plate and change the propagation direction of the projection light;

[0006] The projection light can be incident from the fourth surface to the in-coupling region, and after being reflected by the in-coupling region, the projection light can be reciprocatedly reflected between the intermediate layer and the fourth surface, so that the projection light propagates in the second glass plate; and the projection light propagating in the second glass plate can be incident to the out-coupling region, and after being reflected by the out-coupling region, the projection light can pass through the fourth surface to be emitted from the second glass plate.

[0007] The intermediate layer comprises a polymer layer, a first holographic element arranged in the coupling-in region, and a second holographic element arranged in the coupling-out region, the polymer layer connects the second surface and the third surface, the refractive index of the polymer layer is smaller than the refractive index of the second glass plate, the first holographic element and the second holographic element are fixed to the polymer layer and arranged facing the third surface, and the first holographic element and the second holographic element are arranged at intervals.

[0008] Wherein, the refractive index of the polymer layer is ≤1.52, or ≤1.40, or ≤1.30, or ≤1.20.

[0009] The first holographic element is used to make the projection light have a first angle θ1, and the first angle θ1 is the angle between the projection light reflected by the first holographic element and the normal direction of the second glass plate;

[0010] The first angle θ1 satisfies the following formula: θ1≥arcsin(n2 / n1); wherein n1 is the refractive index of the second glass plate, and n2 is the maximum value between the refractive index of the polymer layer and the refractive index of air.

[0011] The projection light is generated by a projection device, and an incident direction of the projection light from the projection device to the fourth surface is perpendicular to the fourth surface.

[0012] The second holographic element is used to make the projection light have a second angle θ2, which is the angle between the light of the projection light reflected by the second holographic element and the normal direction of the second glass plate, and the projection light also has a third angle θ3, which is the angle between the light of the projection light emitted from the second glass plate and the normal direction of the second glass plate;

[0013] The second angle θ2 and the third angle θ3 satisfy the following formulas: sinθ2×n1=sinθ3×n3, and 1.52×sinθ2=sinθ3; wherein n1 is the refractive index of the second glass plate, and n3 is the refractive index of air.

[0014] The area of ​​the first holographic element is greater than or equal to the area of ​​the projection light incident on the fourth surface; and / or the area of ​​the second holographic element is greater than the area of ​​the first holographic element.

[0015] Wherein, the intermediate layer further includes an auxiliary coupling region, and the auxiliary coupling region is arranged on a side of the out-coupling region away from the in-coupling region; the projection light is reflected by the out-coupling region and the fourth surface in sequence to form a crosstalk light, and the auxiliary coupling region is used to receive the crosstalk light and change the propagation direction of the crosstalk light;

[0016] The crosstalk light can be projected to the auxiliary coupling region, and after being reflected by the auxiliary coupling region, the crosstalk light can be reciprocatedly reflected between the intermediate layer and the fourth surface, so that the crosstalk light propagates in the second glass plate.

[0017] The intermediate layer further comprises a third holographic element arranged in the auxiliary coupling region, the third holographic element is fixed to the polymer layer and arranged facing the third surface, and the third holographic element is arranged on a side of the second holographic element away from the first holographic element.

[0018] The third holographic element is used to make the crosstalk light have a fourth angle θ4, and the fourth angle θ4 is the angle between the crosstalk light reflected by the third holographic element and the normal direction of the second glass plate;

[0019] The fourth angle θ4 satisfies the following formula: θ4≥arcsin(n2 / n1); wherein n1 is the refractive index of the second glass plate, and n2 is the maximum value between the refractive index of the polymer layer and the refractive index of air.

[0020] Wherein, the laminated glass has a light-transmitting area and a shielding area, the visible light transmittance of the light-transmitting area is ≥70%, and the visible light transmittance of the shielding area is ≤5%;

[0021] The first holographic element is arranged in the shielding area, the second holographic element and the third holographic element are both arranged in the light-transmitting area, and the second holographic element is connected to the third holographic element.

[0022] Among them, one first holographic element, one second holographic element, and one third holographic element constitute a holographic element group, the laminated glass has a left-driving area and a right-driving area arranged along the length direction of the laminated glass, one holographic element group is arranged in the left-driving area, and the other holographic element group is arranged in the right-driving area.

[0023] Wherein, along the height direction of the laminated glass, the height of the third holographic element is greater than the height of the second holographic element, and the height of the second holographic element is greater than the height of the first holographic element.

[0024] Wherein, along the height direction of the laminated glass, there is a distance D between the first holographic element and the second holographic element, and the distance D satisfies the following formula: D=2×n×d×tanθ1; wherein n is a positive integer, d is the thickness of the second glass plate, and θ1 is the angle between the light reflected by the first holographic element and the normal direction of the second glass plate.

[0025] The first holographic element, the second holographic element, and the third holographic element are embedded in the polymer layer, and the first holographic element, the second holographic element, the third holographic element, and the polymer layer have the same thickness.

[0026] Wherein, the thickness of the polymer layer is 0.20 mm to 1 mm, or 0.30 mm to 0.90 mm, or 0.40 mm to 0.80 mm.

[0027] Wherein, the absolute value of the difference between the refractive index of the first holographic element and the refractive index of the polymer layer is 0 to 0.01;

[0028] and / or, the absolute value of the difference between the refractive index of the second holographic element and the refractive index of the polymer layer is 0 to 0.01;

[0029] And / or, the absolute value of the difference between the refractive index of the third holographic element and the refractive index of the polymer layer is 0-0.01.

[0030] A second aspect of the present application provides a projection system, which includes a projection device and the laminated glass provided in the first aspect of the present application, wherein the projection device is used to generate projection light, the projection light is projected to the fourth surface, and the laminated glass reflects the projection light to form a display image.

[0031] A third aspect of the present application provides a vehicle, comprising a vehicle body and the projection system provided in the second aspect of the present application, wherein the projection device of the projection system is installed inside the vehicle body, and the laminated glass of the projection system is installed at an opening of the vehicle body.

[0032] The laminated glass, projection system and vehicle provided by the present application, by setting an intermediate layer, the refractive index of the polymer layer is less than the refractive index of the second glass plate, and the refractive index of the air is less than the refractive index of the second glass plate, so that the second glass plate forms an optical waveguide structure, which can also be understood as a light-guiding structure, so that the projection light can propagate in the second glass plate; and, the first holographic element is arranged to change the direction of the projection light, so that the projection light is totally reflected in the second glass plate, and then the second holographic element is used to change the direction of the projection light again, so that the projection light is emitted from the second glass plate and enters the eye, thereby reducing or even eliminating the ghost phenomenon, and improving the display effect of the laminated glass. In addition, a third holographic element is also arranged to change the direction of the crosstalk light, so that the crosstalk light is totally reflected in the second glass plate, thereby avoiding the crosstalk light from being transmitted at the position of the main image, further reducing or even eliminating the ghost phenomenon, further improving the display effect of the laminated glass, and further improving the user experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the technical solutions in the implementation modes of the present application, the drawings required for use in the implementation modes of the present application will be described below.

[0034] Figure 1 A cross-sectional view of a laminated glass provided in accordance with one embodiment of the present application.

[0035] Figure 2 for Figure 1 A partial enlarged view of .

[0036] Figure 3 for Figure 1 Another partial enlargement of .

[0037] Figure 4 A schematic diagram of the structure of a laminated glass provided in one embodiment of the present application.

[0038] Explanation of reference numerals: laminated glass 10, light-transmitting area 101, shielding area 102, left-hand driving area 103, right-hand driving area 104, first glass plate 11, first surface 111, second surface 112, intermediate layer 12, polymer layer 121, first holographic element 122, second holographic element 123, third holographic element 124, second glass plate 13, third surface 131, fourth surface 132, projection device 20. DETAILED DESCRIPTION

[0039] The following are preferred implementations of the present application. It should be noted that, for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present application, and these improvements and modifications are also considered to be within the scope of protection of the present application.

[0040] Unless otherwise specified or there is a contradiction, the terms and phrases used in this application have the following meanings:

[0041] In this application, "first", "second", etc. are used only for descriptive purposes and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features.

[0042] In this application, "one or several" refers to any one, any two or more of the listed items. Among them, "several" refers to any two or more of the listed items.

[0043] The value of x in the chemical formula: if it is clearly defined, it shall be within the defined range. If it is not clearly defined, it can be determined based on the deposition in a stoichiometric, substoichiometric or superstoichiometric manner in the magnetron sputtering process.

[0044] Refractive Index: The refractive index measured at a wavelength of 550 nm.

[0045] like Figure 1 , Figure 2 ,and Figure 3 As shown, the present application provides a laminated glass 10, which includes a first glass plate 11, an intermediate layer 12, and a second glass plate 13, wherein the first glass plate 11 has a first surface 111 and a second surface 112, the second glass plate 13 has a third surface 131 and a fourth surface 132, and the intermediate layer 12 connects the second surface 112 and the third surface 131.

[0046] The refractive index of the intermediate layer 12 is smaller than the refractive index of the second glass plate 13, and the intermediate layer 12 includes an in-coupling region and an out-coupling region that are spaced apart, the in-coupling region is used to receive the projection light incident from the fourth surface 132 and change the propagation direction of the projection light, and the out-coupling region is used to receive the projection light propagating in the second glass plate 13 and change the propagation direction of the projection light.

[0047] The projection light can be incident from the fourth surface 132 to the coupling-in region, and after being reflected by the coupling-in region, the projection light can be reciprocatedly reflected between the intermediate layer 12 and the fourth surface 132, so that the projection light propagates in the second glass plate 13; and the projection light propagating in the second glass plate 13 can be incident to the coupling-out region, and after being reflected by the coupling-out region, the projection light can pass through the fourth surface 132 to be emitted from the second glass plate 13.

[0048] The projection light is generated by the projection device 20, and the projection light is incident on the laminated glass 10. The laminated glass 10 reflects the projection light to form a display image that can be observed by people in the car. In particular, for the driver, the image can be observed without lowering the head, so that the driver has a better field of vision and can use his sight for a longer time to observe the external situation. At the same time, the driver can more easily obtain the necessary information for assisted driving, which greatly improves driving safety, thereby being able to partially replace or even completely replace the traditional instrument panel, or even eliminate the traditional instrument panel.

[0049] The display image formed by the reflection of the projection light through the laminated glass 10 can display vehicle driving information, various patterns or play videos, etc., and can be used in various scenes such as welcoming guests, creating atmosphere, watching movies and working. Optionally, it can be used to display driving parameters, including vehicle speed, engine speed, fuel consumption, tire pressure, warning information, mileage, etc. It can also be used to display weather temperature, entertainment information, and can also be used for dynamic navigation, night vision, real-view maps, etc.

[0050] The first glass plate 11 serves as the outer glass plate of the laminated glass 10. The first glass plate 11 has a first surface 111 and a second surface 112. The first surface 111 faces away from the middle layer 12 and contacts the environment outside the vehicle, and the second surface 112 is close to the middle layer 12. The second glass plate 13 serves as the inner glass plate of the laminated glass 10. The second glass plate 13 has a third surface 131 and a fourth surface 132. The third surface 131 is close to the middle layer 12, and the fourth surface 132 faces away from the middle layer 12 and contacts the environment inside the vehicle. The middle layer 12 connects the second surface 112 and the third surface 131.

[0051] The first glass plate 11 is transparent glass or tinted glass, the thickness of the first glass plate 11 is 1.6 mm to 2.1 mm, and the visible light transmittance of the first glass plate 11 is greater than or equal to 80%. The second glass plate 13 is transparent glass or tinted glass, the thickness of the second glass is 1.6 mm to 2.1 mm, and the visible light transmittance of the second glass plate 13 is greater than or equal to 80%. For example, the first glass plate 11 can be a transparent glass with a thickness of 2.1 mm and a visible light transmittance of 89%, and the second glass plate 13 can be a green glass with a thickness of 1.6 mm and a visible light transmittance of 83%, or a green glass with a thickness of 2.1 mm and a visible light transmittance of 80%. The refractive index of the first glass plate 11 and the second glass plate 13 is 1.45 to 1.90, and can be specifically 1.48, or 1.52, or 1.56, or 1.60, or 1.65, or 1.70, or 1.75, or 1.80, or 1.85, or 1.90, etc.

[0052] The refractive index of the intermediate layer 12 is less than that of the second glass plate 13, and the refractive index of the intermediate layer 12 is ≤ 1.52, and specifically can be 1.52, or 1.50, or 1.45, or 1.40, or 1.35, or 1.30, or 1.25, or 1.20, or 1.15, or 1.10, or 1.05, etc. The refractive index of air is approximately 1. The intermediate layer 12 / second glass plate 13 / air forms a low refractive index layer / high refractive index layer / low refractive index layer, so that the second glass plate 13 forms an optical waveguide structure, which can also be understood as a light guiding structure, which limits the light to propagate in a specific direction and range, so that the projection light can propagate in the second glass plate 13.

[0053] Specifically, after the projection light enters the coupling-in area from the fourth surface 132, it is reflected by the middle layer 12 and reaches the fourth surface 132, and then reflected by the fourth surface 132 and reaches the middle layer 12. The projection light is reflected back and forth between the middle layer 12 and the fourth surface 132, and the above process is repeated. Until the projection light is reflected by the coupling-in area, passes through the fourth surface 132, exits the second glass plate 13, and enters the eye, the ghost phenomenon is reduced or even eliminated, and the display effect of the laminated glass 10 is improved. Figure 1 By adjusting the propagation direction of the projection light in the second glass plate 13 , the projection light can be totally reflected in the second glass plate 13 .

[0054] The laminated glass 10 in the related art uses a PVB film with a wedge angle to make the two reflected images overlap as much as possible to eliminate ghosting, but it cannot fundamentally solve the ghosting phenomenon. However, the present application can replace the wedge-shaped PVB film laminated glass 10 in the related art by setting a laminated glass 10 with a holographic optical waveguide structure, which can effectively eliminate the influence of ghosting, has higher imaging quality, can adapt to different shapes of laminated glass 10, and has flexibility.

[0055] The structure of the intermediate layer 12 is described in detail below. The intermediate layer 12 comprises a polymer layer 121, a first holographic element 122 disposed in the coupling-in region, and a second holographic element 123 disposed in the coupling-out region, the polymer layer 121 connects the second surface 112 and the third surface 131, the refractive index of the polymer layer 121 is smaller than the refractive index of the second glass plate 13, the first holographic element 122 and the second holographic element 123 are fixed to the polymer layer 121 and disposed facing the third surface 131, and the first holographic element 122 and the second holographic element 123 are disposed at intervals.

[0056] The first holographic element 122 is used for receiving the projection light incident from the fourth surface 132 and changing the propagation direction of the projection light so that the projection light propagates in the second glass plate 13. The second holographic element 123 is used for receiving the projection light propagating in the second glass plate 13 and changing the propagation direction of the projection light so that the projection light is emitted from the second glass plate 13. The second holographic element 123 is also used for amplifying the projection light.

[0057] The polymer layer 121 is disposed between the first glass plate 11 and the second glass plate 13, and connects the second surface 112 and the third surface 131. The material of the polymer layer 121 may include one or more of the following materials, such as polycarbonate (PC), polyvinyl chloride (PVC), polyvinyl butyral (PVB), ethylene vinyl acetate (EVA), polyacrylate (PA), polymethyl methacrylate (PMMA), polyurethane (PUR), ionic polymer film (SGP), etc. The refractive index of the polymer layer 121 is ≤1.52, and specifically, it can be 1.52, or 1.50, or 1.45, or 1.40, or 1.35, or 1.30, or 1.25, or 1.20, or 1.15, or 1.10, or 1.05, etc. Preferably, the refractive index of the polymer layer 121 is ≤1.40, more preferably, the refractive index of the polymer layer 121 is ≤1.30, and further preferably, the refractive index of the polymer layer 121 is ≤1.20. The thickness of the polymer layer 121 is 0.20 mm to 1 mm, and specifically, it can be 0.20 mm, or 0.30 mm, or 0.40 mm, or 0.50 mm, or 0.60 mm, or 0.70 mm, or 0.80 mm, or 0.90 mm, or 1 mm, etc. Preferably, the thickness of the polymer layer 121 is 0.30 mm to 0.90 mm, and more preferably, the thickness of the polymer layer 121 is 0.40 mm to 0.80 mm. For example, the thickness of the polymer layer 121 is 0.38 mm, or 0.76 mm. The specific thickness of the polymer layer 121 can be adjusted according to product requirements or user requirements.

[0058] The first holographic element 122 is a diffractive optical element, and its working principle is based on the diffraction principle, rather than the refraction or reflection law of traditional optical elements. The first holographic element 122 can be a holographic optical element (HOE) film. The first holographic element 122 can receive the projection light incident from the fourth surface 132 and change the direction of the projection light so that the projection light is totally reflected in the second glass plate 13.

[0059] The first holographic element 122 is fixed to the polymer layer 121, for example, the first holographic element 122 is bonded to the polymer layer 121. The first holographic element 122 is bonded to the polymer layer 121 by an adhesive, and the adhesive has high transparency to ensure that the visibility of the laminated glass 10 is not affected, thereby reducing the sense of boundary. The adhesive also has good adhesion and can firmly bond the polymer layer 121 and the first holographic element 122 together to ensure the stability and durability of the laminated glass 10. The material of the adhesive can be ethylene vinyl acetate (EVA), polyurethane (PU), etc. The first holographic element 122 is embedded in the polymer layer 121 and connected to the third surface 131. The first holographic element 122 can also be connected to the second surface 112.

[0060] The first holographic element 122 is used to make the projection light have a first angle θ1, which is the angle between the light reflected by the first holographic element 122 and the normal direction of the second glass plate 13. The first angle θ1 satisfies the following formula: θ1≥arcsin(n2 / n1); wherein n1 is the refractive index of the second glass plate 13, and n2 is the maximum value between the refractive index of the polymer layer 121 and the refractive index of air. By limiting the first holographic element 122 to make the incident angle of the projection light the first angle θ1, the incident angle of the projection light is made greater than the critical angle of total reflection of the optical waveguide. Due to the total reflection effect, the projection light can propagate in the optical waveguide structure, thereby reducing or even eliminating the ghost phenomenon, and improving the display effect of the laminated glass 10.

[0061] Furthermore, the projection light is generated by the projection device 20, and the incident direction of the projection light from the projection device 20 to the fourth surface 132 is perpendicular to the fourth surface 132. It can also be understood that the projection light is incident on the fourth surface 132 at an incident angle of 90°. By limiting the incident angle of the projection light from the projection device 20 to the fourth surface 132, it is possible to avoid the incident image generated by the projection device 20 being reflected on the fourth surface 132 to form a ghost image. Specifically, the projection light is incident on the fourth surface 132 vertically, and then on the first holographic element 122.

[0062] The second holographic element 123 is a diffractive optical element, and its working principle is based on the diffraction principle, rather than the refraction or reflection law of traditional optical elements. The second holographic element 123 can be a holographic optical element HOE film. The second holographic element 123 can receive the projection light propagating in the second glass plate 13 and change the direction of the projection light so that the projection light is emitted from the second glass plate 13. The second holographic element 123 can also amplify the projection light.

[0063] Second hologram element 123 is fixed to polymer layer 121, for example, second hologram element 123 is bonded to polymer layer 121. Second hologram element 123 is bonded to polymer layer 121 by an adhesive, and the adhesive has high transparency to ensure that visibility of laminated glass 10 is not affected, thereby reducing the sense of boundary. The adhesive also has good adhesion, and can firmly bond polymer layer 121 and second hologram element 123 together, ensuring stability and durability of laminated glass 10. The material of the adhesive can be ethylene vinyl acetate (EVA), polyurethane (PU), etc. Second hologram element 123 is embedded in polymer layer 121 and connected to third surface 131, and second hologram element 123 can also be connected to second surface 112.

[0064] The second holographic element 123 is used to make the projection light have a second angle θ2, which is the angle between the light reflected by the second holographic element 123 and the normal direction of the second glass plate 13. The projection light also has a third angle θ3, which is the angle between the light emitted from the second glass plate 13 and the normal direction of the second glass plate 13. The second angle θ2 and the third angle θ3 satisfy the following formulas: sinθ2×n1=sinθ3×n3, and 1.52×sinθ2=sinθ3; wherein n1 is the refractive index of the second glass plate 13, and n3 is the refractive index of air. The second holographic element 123 changes the direction of the projection light so that the projection light has the second angle θ2, thereby eliminating the total reflection of the projection light in the second glass plate 13, so that the projection light is emitted from the second glass plate 13 and enters the human eye. The changed angle is related to the position of the human eye and has flexibility. At the same time, the second holographic element 123 also plays a role in magnifying the image, further improving the display effect of the laminated glass 10 .

[0065] The area of ​​the first holographic element 122 is greater than or equal to the area of ​​the projection light incident on the fourth surface 132. The area of ​​the first holographic element 122 matches the area of ​​the projection light projected on the fourth surface 132, which is beneficial for the first holographic element 122 to receive and reflect more projection light, thereby improving the display effect of the laminated glass 10.

[0066] And / or, the area of ​​the second holographic element 123 is larger than that of the first holographic element 122 , which is beneficial for the second holographic element 123 to receive and reflect more projection light, thereby improving the display effect of the laminated glass 10 .

[0067] In one embodiment, the intermediate layer 12 further includes an auxiliary coupling region, which is disposed on a side of the out-coupling region away from the in-coupling region; the projection light is sequentially reflected by the out-coupling region and the fourth surface 132 to form a crosstalk light, and the auxiliary coupling region is used to receive the crosstalk light and change the propagation direction of the crosstalk light;

[0068] The crosstalk light can be projected to the auxiliary coupling region, and after being reflected by the auxiliary coupling region, the crosstalk light can be reciprocally reflected between the intermediate layer 12 and the fourth surface 132, so that the crosstalk light propagates in the second glass plate 13. Figure 1 As shown in L2.

[0069] In this embodiment, an auxiliary coupling area is provided to cooperate with the out-coupling area so that the crosstalk light is propagated in the second glass plate 13, thereby causing the crosstalk light to be totally reflected in the second glass plate 13, thereby preventing the crosstalk light from being transmitted at the position of the main image, further reducing or even eliminating the ghost phenomenon, further improving the display effect of the laminated glass 10, and further improving the user experience.

[0070] The intermediate layer 12 further comprises a third holographic element 124 arranged in the auxiliary coupling region. The third holographic element 124 is fixed to the polymer layer 121 and faces the third surface 131 . The third holographic element 124 is arranged on a side of the second holographic element 123 away from the first holographic element 122 .

[0071] The projection light is reflected by the second holographic element 123 and the fourth surface 132 in sequence to form crosstalk light. The third holographic element 124 is used to receive the crosstalk light and change the propagation direction of the crosstalk light so that the crosstalk light propagates in the second glass plate 13.

[0072] The third holographic element 124 is a diffractive optical element, and its working principle is based on the diffraction principle, rather than the refraction or reflection law of traditional optical elements. The third holographic element 124 can be a holographic optical element HOE film. The third holographic element 124 can receive the crosstalk light and change the direction of the crosstalk light, so that the crosstalk light is totally reflected in the second glass plate 13.

[0073] The third hologram element 124 is fixed to the polymer layer 121, for example, the third hologram element 124 is bonded to the polymer layer 121. The third hologram element 124 is bonded to the polymer layer 121 by an adhesive, and the adhesive has high transparency to ensure that the visibility of the laminated glass 10 is not affected, thereby reducing the sense of boundary. The adhesive also has good adhesion, and can firmly bond the polymer layer 121 and the third hologram element 124 together to ensure the stability and durability of the laminated glass 10. The material of the adhesive can be ethylene vinyl acetate (EVA), polyurethane (PU), etc. The third hologram element 124 is embedded in the polymer layer 121 and connected to the third surface 131. The third hologram element 124 can also be connected to the second surface 112. Compared with the second hologram element 123, the third hologram element 124 is far away from the first hologram element 122, and the third hologram element 124 is connected to the second hologram element 123.

[0074] The third holographic element 124 is used to make the crosstalk light have a fourth angle θ4, and the fourth angle θ4 is the angle between the crosstalk light reflected by the third holographic element 124 and the normal direction of the second glass plate 13. The fourth angle θ4 satisfies the following formula: θ4≥arcsin(n2 / n1); wherein n1 is the refractive index of the second glass plate 13, and n2 is the maximum value between the refractive index of the polymer layer 121 and the refractive index of air.

[0075] Since the projection light reflected by the second holographic element 123 will be reflected by the fourth surface 132, crosstalk light is formed, and the crosstalk light has caused the ghost image. Therefore, the present application limits the third holographic element 124 to make the incident angle of the crosstalk light a fourth angle θ4, so that the incident angle of the crosstalk light is greater than the critical angle of total reflection of the optical waveguide. Due to the total reflection effect, the crosstalk light can propagate in the optical waveguide structure, thereby avoiding the crosstalk light from being transmitted at the position of the main image, further reducing or even eliminating the ghost image phenomenon, further improving the display effect of the laminated glass 10, and further improving the user experience.

[0076] like Figure 4 As shown, Figure 4 The structure diagram of the laminated glass 10 is viewed from the perspective of the interior of the vehicle. The laminated glass 10 has a light-transmitting area 101 and a shielding area 102. The visible light transmittance of the light-transmitting area 101 is ≥70%, and the visible light transmittance of the shielding area 102 is ≤5%. The first holographic element 122 is arranged in the shielding area 102, the second holographic element 123 and the third holographic element 124 are both arranged in the light-transmitting area 101, and the second holographic element 123 is connected to the third holographic element 124.

[0077] The shielding area 102 is also commonly referred to as a black border area. Preferably, the shielding area 102 is a bottom shielding area provided below the light-transmitting area 101. Optionally, the laminated glass 10 further includes a shielding layer provided on the second surface 112 and / or the fourth surface 132, and the shielding layer is provided in the shielding area 102. The shielding layer can block the external ambient light to avoid unnecessary interference of the line of sight, and can also improve the contrast between the displayed image and the displayed background and achieve a higher color gamut, so that the image display is clearer. The material of the shielding layer is selected from at least one of dark ink, an opaque polymer film, and a dimming film.

[0078] And, if Figure 4 As shown, one first holographic element 122, one second holographic element 123, and one third holographic element 124 form a holographic element group, the laminated glass 10 has a left driving area 103 and a right driving area 104 arranged along the length direction of the laminated glass 10, one holographic element group is arranged in the left driving area 103, and the other holographic element group is arranged in the right driving area 104. By arranging the two holographic element groups in the left driving area 103 and the right driving area 104 respectively, the user corresponding to the left driving area 103 and the user corresponding to the right driving area 104 can clearly observe the display image formed by the projection light, reduce or even eliminate the ghost phenomenon, and improve the display effect of the laminated glass 10.

[0079] Along the height direction of the laminated glass 10, the height of the third holographic element 124 (eg Figure 4 H3 in the figure) is greater than the height of the second holographic element 123 (as shown in Figure 4 The height of the second holographic element 123 (shown as H2) is Figure 4 ) is greater than the height of the first holographic element 122 (as shown in H2 Figure 4 (as shown in H1).

[0080] Since the projection light irradiating onto first hologram element 122 may not be completely irradiated onto the center of first hologram element 122 but may be irradiated onto its edge, in order to ensure that the light reflected by first hologram element 122 is completely received by second hologram element 123, the height of second hologram element 123 is made greater than that of first hologram element 122, so that second hologram element 123 can receive more projection light.

[0081] Furthermore, since the second hologram element 123 has the function of magnifying the image, in order to completely receive the light reflected by the fourth surface 132, the height of the third hologram element 124 is made greater than the height of the second hologram element 123 to ensure that the third hologram element 124 receives more crosstalk light, thereby reducing or even eliminating the ghost phenomenon, thereby improving the display effect of the laminated glass 10.

[0082] The specific positions, heights, and widths of the first holographic element 122, the second holographic element 123, and the third holographic element 124 need to be determined according to the installation position of the projection device 20 of different vehicle models, the FOV field of view, and the eye box position, and are not limited here.

[0083] First hologram element 122, second hologram element 123, and third hologram element 124 are flexible. First hologram element 122, second hologram element 123, and third hologram element 124 can match with the curved glass plate. In addition, the image enlargement and reduction of the curved laminated glass 10 can be offset by one reflection between the third surface 131 and the fourth surface 132. The fourth surface 132 can be regarded as a convex mirror, and the third surface 131 can be regarded as a concave mirror, so the display effect of the laminated glass 10 will not be affected.

[0084] Along the height direction of the laminated glass 10, there is a distance D between the first holographic element 122 and the second holographic element 123, and the distance D satisfies the following formula: D=2×n×d×tanθ1; wherein n is a positive integer, d is the thickness of the second glass plate 13, and θ1 is the angle between the light reflected by the first holographic element 122 and the normal direction of the second glass plate 13. The distance between the first holographic element 122 and the second holographic element 123 is defined by the above formula, so as to ensure that the projection light reflected by the first holographic element 122 can be received by the second holographic element 123, so that the projection light is emitted from the second glass plate 13 and enters the eye, thereby reducing or even eliminating the ghost phenomenon, and improving the display effect of the laminated glass 10.

[0085] The first hologram element 122, the second hologram element 123, and the third hologram element 124 are embedded in the polymer layer 121, and the first hologram element 122, the second hologram element 123, the third hologram element 124, and the polymer layer 121 have the same thickness. By limiting the thickness of the first hologram element 122, the second hologram element 123, the third hologram element 124, and the polymer layer 121 to be equal, the bulging phenomenon of the laminated glass 10 can be avoided, and the reliability of the laminated glass 10 can be improved.

[0086] The absolute value of the difference between the refractive index of the first holographic element 122 and the refractive index of the polymer layer 121 is 0 to 0.01. The absolute value of the difference between the refractive index of the first holographic element 122 and the refractive index of the polymer layer 121 can be 0.001, 0.002, 0.003, 0.004, 0.005, 0.006, 0.007, 0.008, 0.009, 0.01, etc.

[0087] And / or, the absolute value of the difference between the refractive index of the second holographic element 123 and the refractive index of the polymer layer 121 is 0 to 0.01. The absolute value of the difference between the refractive index of the second holographic element 123 and the refractive index of the polymer layer 121 can be 0.001, 0.002, 0.003, 0.004, 0.005, 0.006, 0.007, 0.008, 0.009, 0.01, etc.

[0088] And / or, the absolute value of the difference between the refractive index of the third holographic element 124 and the refractive index of the polymer layer 121 is 0 to 0.01. The absolute value of the difference between the refractive index of the third holographic element 124 and the refractive index of the polymer layer 121 can be 0.001, 0.002, 0.003, 0.004, 0.005, 0.006, 0.007, 0.008, 0.009, 0.01, etc.

[0089] By limiting the absolute value of the difference in refractive index between the polymer layer 121 and the first holographic element 122, the second holographic element 123, and the third holographic element 124, the polymer layer 121 can better cooperate with each holographic element, and better limit the propagation of the projection light in a specific direction and range, thereby reducing or even eliminating the ghost phenomenon and improving the display effect of the laminated glass 10.

[0090] The present application can fundamentally solve the problem of ghost images caused by the image being reflected twice on the first and fourth surfaces of the laminated glass by setting the first holographic element, the second holographic element, and the third holographic element in coordination with the polymer layer. The image is reflected into the optical waveguide structure only through the first holographic element, and the image is propagated through the optical waveguide structure, and finally emitted through the second holographic element and enters the human eye. The remaining reflected light continues to be confined in the second glass plate through the third holographic element, and is emitted at a position that does not affect the main image, thereby significantly improving the display effect of the laminated glass and improving the user experience.

[0091] The present application provides a projection system, which includes a projection device and the laminated glass provided above in the present application, wherein the projection device is used to generate projection light, the projection light is projected to the fourth surface, and the laminated glass reflects the projection light to form a display image.

[0092] The wavelength of the projection light may be in the range of 380nm to 780nm. The projection light may contain at least 80% of P-polarized light. The higher the proportion of P-polarized light in the projection light, the more conducive it is to meeting the use needs of drivers wearing sunglasses and the easier it is to eliminate the visual ghosting phenomenon of the displayed image.

[0093] The present application provides a vehicle, which includes a vehicle body and the projection system provided in the present application above, wherein a projection device of the projection system is installed inside the vehicle body, and a laminated glass of the projection system is installed at an opening of the vehicle body.

[0094] When the laminated glass is installed on a vehicle, it is preferably used as the front windshield of the vehicle. However, it is not limited thereto, and the laminated glass can also be used as the rear windshield or side window glass, thereby providing more display scene applications for the vehicle.

[0095] The above is a detailed introduction to the contents provided in the implementation mode of the present application. This article explains and illustrates the principles and implementation modes of the present application. The above explanation is only used to help understand the method and core idea of ​​the present application. At the same time, for those skilled in the art, according to the idea of ​​the present application, there will be changes in the specific implementation mode and application scope. In summary, the contents of this specification should not be understood as limiting the present application.

Claims

1. A laminated glass, characterized in that: The laminated glass comprises a first glass plate, an intermediate layer, and a second glass plate, wherein the first glass plate has a first surface and a second surface, the second glass plate has a third surface and a fourth surface, and the intermediate layer connects the second surface and the third surface; The refractive index of the intermediate layer is smaller than the refractive index of the second glass plate, and the intermediate layer includes an incoupling region and an outcoupling region which are spaced apart, the incoupling region is used to receive the projection light incident from the fourth surface and change the propagation direction of the projection light, and the outcoupling region is used to receive the projection light propagating in the second glass plate and change the propagation direction of the projection light; The projection light can be incident from the fourth surface to the in-coupling region, and after being reflected by the in-coupling region, the projection light can be reciprocatedly reflected between the intermediate layer and the fourth surface, so that the projection light propagates in the second glass plate; and the projection light propagating in the second glass plate can be incident to the out-coupling region, and after being reflected by the out-coupling region, the projection light can pass through the fourth surface to be emitted from the second glass plate.

2. The laminated glass according to claim 1, characterized in that: The intermediate layer comprises a polymer layer, a first holographic element arranged in the coupling-in region, and a second holographic element arranged in the coupling-out region, the polymer layer connects the second surface and the third surface, the refractive index of the polymer layer is smaller than the refractive index of the second glass plate, the first holographic element and the second holographic element are fixed to the polymer layer and arranged facing the third surface, and the first holographic element and the second holographic element are arranged at an interval.

3. The laminated glass according to claim 2, characterized in that: The refractive index of the polymer layer is ≤1.52, or ≤1.40, or ≤1.30, or ≤1.

20.

4. The laminated glass according to claim 2, characterized in that: The first holographic element is used to make the projection light have a first angle θ1, where the first angle θ1 is the angle between the projection light reflected by the first holographic element and the normal direction of the second glass plate; The first angle θ1 satisfies the following formula: θ1≥arcsin(n2 / n1); wherein n1 is the refractive index of the second glass plate, and n2 is the maximum value between the refractive index of the polymer layer and the refractive index of air.

5. The laminated glass according to claim 2, characterized in that: The projection light is generated by a projection device, and an incident direction of the projection light from the projection device to the fourth surface is perpendicular to the fourth surface.

6. The laminated glass according to claim 2, characterized in that: The second holographic element is used to make the projection light have a second angle θ2, which is the angle between the light of the projection light reflected by the second holographic element and the normal direction of the second glass plate. The projection light also has a third angle θ3, which is the angle between the light of the projection light emitted from the second glass plate and the normal direction of the second glass plate. The second angle θ2 and the third angle θ3 satisfy the following formulas: sinθ2×n1=sinθ3×n3, and 1.52×sinθ2=sinθ3; wherein n1 is the refractive index of the second glass plate, and n3 is the refractive index of air.

7. The laminated glass according to claim 2, characterized in that: The area of ​​the first holographic element is greater than or equal to the area of ​​the projection light incident on the fourth surface; and / or the area of ​​the second holographic element is greater than the area of ​​the first holographic element.

8. The laminated glass according to claim 2, characterized in that: The intermediate layer further comprises an auxiliary coupling region, which is arranged on a side of the out-coupling region away from the in-coupling region; the projection light is reflected by the out-coupling region and the fourth surface in sequence to form a crosstalk light, and the auxiliary coupling region is used to receive the crosstalk light and change the propagation direction of the crosstalk light; The crosstalk light can be projected to the auxiliary coupling region, and after being reflected by the auxiliary coupling region, the crosstalk light can be reciprocatedly reflected between the intermediate layer and the fourth surface, so that the crosstalk light propagates in the second glass plate.

9. The laminated glass according to claim 8, characterized in that: The intermediate layer further comprises a third holographic element arranged in the auxiliary coupling region, the third holographic element is fixed to the polymer layer and arranged facing the third surface, and the third holographic element is arranged on a side of the second holographic element facing away from the first holographic element.

10. The laminated glass according to claim 9, characterized in that: The third holographic element is used to make the crosstalk light have a fourth angle θ4, where the fourth angle θ4 is the angle between the crosstalk light reflected by the third holographic element and the normal direction of the second glass plate; The fourth angle θ4 satisfies the following formula: θ4≥arcsin(n2 / n1); wherein n1 is the refractive index of the second glass plate, and n2 is the maximum value between the refractive index of the polymer layer and the refractive index of air.

11. The laminated glass according to claim 9, characterized in that: The laminated glass has a light-transmitting area and a shielding area, the visible light transmittance of the light-transmitting area is ≥70%, and the visible light transmittance of the shielding area is ≤5%; The first holographic element is arranged in the shielding area, the second holographic element and the third holographic element are both arranged in the light-transmitting area, and the second holographic element is connected to the third holographic element.

12. The laminated glass according to claim 9, characterized in that: One first holographic element, one second holographic element, and one third holographic element constitute a holographic element group. The laminated glass has a left-riding area and a right-riding area arranged along the length direction of the laminated glass. One holographic element group is arranged in the left-riding area, and the other holographic element group is arranged in the right-riding area.

13. The laminated glass according to claim 9, characterized in that: Along the height direction of the laminated glass, the height of the third hologram element is greater than the height of the second hologram element, and the height of the second hologram element is greater than the height of the first hologram element.

14. The laminated glass according to claim 9, characterized in that: Along the height direction of the laminated glass, there is a distance D between the first holographic element and the second holographic element, and the distance D satisfies the following formula: D=2×n×d×tanθ1; wherein n is a positive integer, d is the thickness of the second glass plate, and θ1 is the angle between the light reflected by the first holographic element and the normal direction of the second glass plate.

15. The laminated glass according to claim 9, characterized in that: The first holographic element, the second holographic element, and the third holographic element are embedded in the polymer layer, and the first holographic element, the second holographic element, the third holographic element, and the polymer layer have the same thickness.

16. The laminated glass according to claim 15, characterized in that: The thickness of the polymer layer is 0.20 mm to 1 mm, or 0.30 mm to 0.90 mm, or 0.40 mm to 0.80 mm.

17. The laminated glass according to claim 9, characterized in that: The absolute value of the difference between the refractive index of the first holographic element and the refractive index of the polymer layer is 0 to 0.01; and / or, the absolute value of the difference between the refractive index of the second holographic element and the refractive index of the polymer layer is 0 to 0.01; And / or, the absolute value of the difference between the refractive index of the third holographic element and the refractive index of the polymer layer is 0-0.

01.

18. A projection system, characterized in that: The projection system comprises a projection device and the laminated glass according to any one of claims 1 to 17, wherein the projection device is used to generate projection light, the projection light is projected onto the fourth surface, and the laminated glass reflects the projection light to form a display image.

19. A vehicle, characterized in that: The vehicle comprises a vehicle body, and the projection system according to claim 18, wherein a projection device of the projection system is installed inside the vehicle body, and a laminated glass of the projection system is installed at an opening of the vehicle body.

Images