US-12617185-B2 - Laminated pane with retardation plate

Abstract

A laminated pane having a projection region and a main see-through region, includes an outer pane, at least one thermoplastic intermediate layer, a reflective layer, an opaque masking layer, an inner pane, an adhesive layer, and a λ/4 retardation plate, wherein the at least one thermoplastic intermediate layer is arranged between the outer pane and the inner pane, the projection region is arranged outside the main see-through region, the reflective layer is arranged at least in the projection region between the outer pane and the inner pane, the opaque masking layer is arranged at least in the projection region between the outer pane and the inner pane and, when viewed through the laminated pane, is arranged spatially behind the reflective layer, starting from the interior-side surface of the inner pane, and the λ/4 retardation plate is connected via the adhesive layer to the interior-side surface of the inner pane.

Inventors

• Andreas Gomer
• Jan Hagen
• Julian GREVERATH

Assignees

• SAINT-GOBAIN GLASS FRANCE

Dates

Publication Date

20260505

Application Date

20230322

Priority Date

20220330

Claims (20)

1. 1 . A laminated pane having a projection region, a main see-through region, an upper edge, a lower edge and two lateral pane edges, at least comprising an outer pane, at least one thermoplastic intermediate layer, a reflective layer, an opaque masking layer, an inner pane, an adhesive layer, and a λ/4 retardation plate, wherein the outer pane has an exterior-side surface facing away from the at least one thermoplastic intermediate layer, and an interior-side surface facing the at least one thermoplastic intermediate layer, and the inner pane has an exterior-side surface facing the at least one thermoplastic intermediate layer and an interior-side surface facing away from the at least one thermoplastic intermediate layer, the projection region is arranged outside the main see-through region, the reflective layer is arranged at least in the projection region between the outer pane and the inner pane, the opaque masking layer is arranged at least in the projection region between the outer pane and the inner pane and, when viewed through the laminated pane, is arranged spatially behind the reflective layer, starting from the interior-side surface of the inner pane, the λ/4 retardation plate is connected via the adhesive layer to the interior-side surface of the inner pane and is arranged in a region of the laminated pane which, when viewed perpendicularly through the laminated pane, lies completely in the region in which the opaque masking layer is arranged, and the projection region lies completely in the region of the laminated pane in which the λ/4 retardation plate is arranged, when viewed perpendicularly through the laminated pane.
2. 2 . The laminated pane according to claim 1 , wherein the reflective layer is arranged substantially over the entire surface between the outer pane and the inner pane.
3. 3 . The laminated pane according to claim 1 , wherein the reflective layer is arranged between the outer pane and the inner pane in a region of the laminated pane which, when viewed perpendicularly through the laminated pane, lies completely in the region in which the opaque masking layer is arranged.
4. 4 . The laminated pane according to claim 1 , wherein the reflective layer is arranged between the inner pane and the at least one thermoplastic intermediate layer or between the outer pane and the at least one thermoplastic intermediate layer, or wherein the laminated pane comprises at least two thermoplastic intermediate layers and the reflective layer is arranged between two of the thermoplastic intermediate layers.
5. 5 . The laminated pane according to claim 1 , wherein the adhesive layer is a thermoplastic polymer layer or an optically clear adhesive.
6. 6 . The laminated pane according to claim 1 , wherein the projection region is arranged adjacent to the lower edge of the laminated pane.
7. 7 . The laminated pane according to claim 1 , wherein the opaque masking layer is arranged at least partially in a peripheral edge region.
8. 8 . The laminated pane according to claim 7 , wherein the opaque masking layer has in a section which overlaps with the projection region a greater width than in sections different therefrom.
9. 9 . The laminated pane according to claim 1 , wherein the opaque masking layer is designed as an opaque cover print on the interior-side surface of the outer pane or as an opaquely colored region of the at least one thermoplastic intermediate layer.
10. 10 . The laminated pane according to claim 1 , wherein the reflective layer is designed as a reflective coating or as a reflective film.
11. 11 . The laminated pane according to claim 1 , additionally comprising a coating which is designed as a protective coating or an anti-reflection coating and is arranged on the surface of the λ/4 retardation plate facing away from the adhesive layer.
12. 12 . A projection arrangement comprising: a laminated pane according to claim 1 , and an image display device which is directed toward the projection region and is arranged in such a way that the interior-side surface of the inner pane is the surface of the inner pane closest to the image display device.
13. 13 . The projection arrangement according to claim 12 , wherein the image display device is a projector or a display.
14. 14 . The projection arrangement according to claim 13 , wherein the display is an LCD display, a LED display, a microLED display, an OLED display or an electroluminescent display.
15. 15 . The projection arrangement according to claim 13 , wherein the radiation strikes the laminated pane at an angle of incidence of 55° to 80°.
16. 16 . The projection arrangement according to claim 15 , wherein the radiation strikes the laminated pane at an angle of incidence of 62° to 77°.
17. 17 . The projection arrangement according to claim 12 , wherein the image display device emits s-polarized light.
18. 18 . The projection arrangement according to claim 12 , wherein the image display device emits circularly polarized light.
19. 19 . A method comprising providing a laminated pane according to claim 1 as a vehicle pane in means of transport for traffic on land, in the air or on water.
20. 20 . The method according to claim 19 , wherein the vehicle pane is a windshield for a head-up display.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application is the U.S. National Stage of PCT/EP2023/057259, filed Mar. 22, 2023, which in turn claims priority to European patent application number 22165378.5 filed Mar. 30, 2022. The content of these applications are incorporated herein by reference in their entirety. The invention relates to a laminated pane with a λ/4 retardation plate, a projection arrangement and the use of the laminated pane. In order to display navigation information in windshields, projection arrangements known under the term of head-up displays (HUD) consisting of an image display device and windshield with a wedge-angle thermoplastic intermediate layer and/or with wedge-angle panes are often used. A wedge angle is necessary to avoid double images. The projected image appears in the form of a virtual image at a certain distance from the windshield so that the driver of the motor vehicle sees, for example, the projected navigation information as being in front of him on the road. Typically, the radiation from HUD image display devices is substantially s-polarized due to the better reflection characteristics of the windshield compared to p-polarization. However, if the viewer wears polarization-selective sun glasses which do not transmit any s-polarized light, he will perceive the HUD image dimmer at best. A solution to this problem is the use of projection arrangements that employ p-polarized light. DE102014220189A1 discloses a head-up display projection arrangement which is operated with p-polarized radiation, wherein the windshield has a reflective structure which reflects p-polarized radiation in the direction of the viewer. US20040135742A1 also discloses a head-up display projection arrangement using p-polarized radiation which has a reflective structure. WO 96/19347A3 proposes a multi-layer polymer layer as a reflective structure. When designing a display which is based on the head-up display technology, it must also be ensured that the image display device has a correspondingly strong power so that the projected image has sufficient brightness and can be easily seen by the viewer, in particular when sunlight is incident. This requires a certain size of the image display device and is associated with a corresponding power consumption. Accordingly, there is a need for improved laminated panes for projection arrangements with which these disadvantages can be avoided. There is therefore a need for improved laminated panes for projection arrangements in which the projection arrangements have a strong contrast of the generated image, even with oncoming light, and a low energy consumption, and in which projected images for a viewer who is wearing polarization-selective sunglasses can be easily perceived. The object of the present invention is to provide such an improved laminated pane, a method for the production thereof and a use thereof, and to provide an improved projection arrangement with an improved laminated pane. This object is achieved according to the invention by a laminated pane according to claim 1, a projection arrangement, and a use according to the independent claims. Preferred embodiments result from the dependent claims. The laminated pane according to the invention comprises an outer pane, at least one thermoplastic intermediate layer, a reflective layer, an opaque masking layer, an inner pane, an adhesive layer, and a λ/4 retardation plate. The laminated pane has a main see-through region and a projection region. The laminated pane is provided to separate the interior from the external environment in a window opening of a vehicle. Within the meaning of the invention, the term “inner pane” refers to the pane of the laminated pane facing the vehicle interior. Outer pane means the pane facing the external environment. The laminated pane has an upper edge and a lower edge and two side edges extending between them. Upper edge means the edge intended to point upward in the installed position. Lower edge means the edge intended to point downward in the installed position. In the case of a windshield, the upper edge is often also referred to as the roof edge and the lower edge is referred to as the motor edge. The outer pane and the inner pane each have an exterior-side and an interior-side surface and a peripheral side edge extending between them. In the context of the invention, the exterior-side surface means the main surface which is provided to face the external environment when installed. In the context of the invention, the interior-side surface means the main surface that is provided to face the interior in the installation position. The interior-side surface of the outer pane and the exterior-side surface of the inner pane face one another and are connected to one another by the at least one thermoplastic intermediate layer. The exterior-side surface of the outer pane therefore faces away from the at least one thermoplastic intermediate layer, and the interior-side s