Composite sheet body with retardation plate

Abstract

The invention relates to a composite sheet (1) having a projection region (B) and a main perspective region (H), at least comprising an outer sheet (2), at least one thermoplastic intermediate layer (3), a reflective layer (4), an opaque masking layer (5), an inner sheet (6), an adhesive layer (7) and a lambda / 4 retardation plate (8), the at least one thermoplastic intermediate layer (3) being arranged between the outer sheet (2) and the inner sheet (6), the reflective layer (4) being arranged between the outer sheet (2) and the inner sheet (6), the adhesive layer (7) being arranged between the outer sheet (2) and the inner sheet (6), and the lambda / 4 retardation plate (8) being arranged between the outer sheet (2) and the inner sheet (6). The projection region (B) is arranged outside the main perspective region (H), the reflective layer (4) is arranged at least in the projection region (B) between the outer sheet (2) and the inner sheet (6), and the opaque masking layer (5) is arranged at least in the projection region (B) between the outer sheet (2) and the inner sheet (6), and a lambda / 4 retardation plate (8) which is arranged spatially behind the reflective layer (4) when seen through the composite sheet (1) from the inner-chamber-side surface (IV) of the inner sheet (6), which lambda / 4 retardation plate (8) is connected to the inner-chamber-side surface (IV) of the inner sheet (6) via the adhesive layer (7) and is arranged in the following region of the composite sheet (1), the projection region (B) is located completely in the region in which the opaque masking layer (5) is arranged when passing through the composite sheet (1) in a vertical perspective manner, and wherein the projection region (B) is located completely in the region of the composite sheet (1) in which the lambda / 4 retardation plate (8) is arranged when passing through the composite sheet (1) in a vertical perspective manner.

Description

Technical Field

[0001] The present invention relates to a composite sheet having a λ / 4 retardation plate, a projection assembly, and an application of the composite sheet. Background Art

[0002] In order to display navigation information in a windshield, a projection assembly known by the term head-up display (HUD) is generally used. The projection assembly includes an image display device and a windshield having a wedge-shaped thermoplastic interlayer and / or a wedge-shaped sheet. Here, in order to avoid double images, a wedge angle is required. The projected image appears in the form of a virtual image at a certain distance from the windshield, so that a driver of a motor vehicle, for example, perceives the projected navigation information as being in front of the driver on the road. Due to the better reflection characteristics of the windshield compared to p-polarization, the radiation of the HUD image display device is generally substantially s-polarized. However, if the observer wears polarization-selective sunglasses that do not transmit s-polarized light, the observer may perceive the HUD image weakly. A solution to this problem is to use a projection assembly that employs p-polarized light.

[0003] DE102014220189A1 discloses a head-up display projection assembly that operates using p-polarized radiation, wherein the windshield has a reflective structure that reflects p-polarized radiation in the direction of the observer. US20040135742A1 also discloses a head-up display projection assembly that uses p-polarized radiation and has a reflective structure. In WO96 / 19347A3, a multilayer polymer layer is proposed as a reflective structure.

[0004] In the design of a display based on head-up display technology, it must also be considered that the image display device has a relatively large power, so that the projected image has sufficient brightness especially when sunlight is incident and can be seen well by the observer. This requires a certain size of the image display device and is accompanied by a corresponding power consumption. Summary of the Invention

[0005] Therefore, there is a need for an improved composite sheet for a projection assembly, by means of which these disadvantages can be avoided. Therefore, there is a need for an improved composite sheet for a projection assembly, wherein the projection assembly has good contrast of the generated image even in a backlight situation and has low energy consumption, and wherein the projected image can be well perceived by an observer wearing polarization-selective sunglasses. The object of the present invention is to provide such an improved composite sheet, a method for manufacturing a composite sheet and an application of the composite sheet, and an improved projection assembly with an improved composite sheet.

[0006] This task is solved according to the invention by means of a composite sheet according to claim 1, a projection assembly and an application according to the dependent claims. Preferred embodiments result from the dependent claims.

[0007] The composite sheet according to the invention comprises an outer sheet, at least one thermoplastic intermediate layer, a reflective layer, an opaque masking layer, an inner sheet, an adhesive layer and a λ / 4 retardation plate.

[0008] The composite sheet has a main perspective region and a projection region.

[0009] The composite sheet is provided for separating the interior from the external environment in a window opening of a vehicle. In the sense of the present invention, the inner sheet denotes the sheet of the composite sheet facing the interior of the vehicle. The outer sheet denotes the sheet facing the external environment.

[0010] The composite sheet has an upper edge and a lower edge and two side edges extending therebetween. The upper edge is denoted as the edge which is provided for pointing upwards in the installation position. The lower edge is denoted as the edge which is provided for pointing downwards in the installation position. In the case of a windscreen, the upper edge is often also referred to as the roof edge and the lower edge is often referred to as the motor edge.

[0011] The outer sheet and the inner sheet each have an outer and an interior-side surface and a surrounding side edge extending therebetween. In the sense of the present invention, the outer surface denotes the main surface which is provided for facing the external environment in the installation position. In the sense of the present invention, the interior-side surface denotes the main surface which is provided for facing the interior in the installation position. The interior-side surface of the outer sheet and the outer surface of the inner sheet face each other and are interconnected by means of at least one thermoplastic intermediate layer. Thus, the outer surface of the outer sheet faces away from the at least one thermoplastic intermediate layer, and the interior-side surface of the outer sheet faces the at least one thermoplastic intermediate layer. The outer surface of the inner sheet faces the at least one thermoplastic intermediate layer, and the interior-side surface of the inner sheet faces away from the at least one thermoplastic intermediate layer.

[0012] The outer surface of the outer sheet is designated as side I. The interior-side surface of the outer sheet is designated as side II. The outer surface of the inner sheet is designated as side III. The interior-side surface of the inner sheet is designated as side IV.

[0013] According to the present invention, the projection area is arranged outside the main perspective area. This means that the projection area and the main perspective area do not overlap with each other. In a preferred embodiment, the main perspective area and the projection area are arranged spaced apart from each other, that is to say, in this embodiment, the main perspective area and the projection area are not arranged adjacent to each other. In a further embodiment, the projection area and the main perspective area are arranged adjacent to each other, that is to say, in this embodiment, the main perspective area and the projection area are arranged directly adjacent to each other.

[0014] The reflective layer is adapted to reflect light. Therefore, the reflective layer is a layer that reflects light. The reflective layer is, for example, adapted to reflect p-polarized light and / or reflect circularly polarized light. Therefore, the reflective layer can be configured as a layer that reflects p-polarized light and / or configured as a layer that reflects circularly polarized light. According to the present invention, the reflective layer is arranged between the outer sheet and the inner sheet and is arranged at least in the projection area.

[0015] The reflective layer preferably reflects at least 5%, particularly preferably at least 10%, of the light incident on the reflective layer within a wavelength range of 450 nm to 650 nm and an incident angle of 55° to 75°. Particularly preferably, the reflective layer reflects 30% or more, particularly preferably 50% or more, very particularly preferably 70% or more, and especially 90% or more of the light incident on the reflective layer.

[0016] The opaque masking layer is arranged between the outer sheet and the inner sheet at least in the projection area and is spatially arranged behind the reflective layer when looking through the composite sheet from the surface on the inner chamber side of the inner sheet. Therefore, in the installed state of the composite sheet according to the present invention in a vehicle, the reflective layer has a smaller distance to the vehicle interior compared to the opaque masking layer.

[0017] It can be understood that the opaque masking layer is arranged outside the main perspective area of the composite sheet. Since the opaque masking layer is arranged outside the main perspective area, the transparency of the composite sheet in the main perspective area is not affected by the opaque masking layer.

[0018] The λ / 4 retardation plate is connected to the surface on the inner chamber side of the inner sheet via an adhesive layer. When looking vertically through the composite sheet, the λ / 4 retardation plate is arranged in the following area of the composite sheet, which area is completely within the area where the opaque masking layer is arranged.

[0019] According to the present invention, the projection area is completely within the area of the composite sheet where the λ / 4 retardation plate is arranged when looking vertically through the composite sheet. Therefore, in a vertical observation through the composite sheet or in an orthogonal projection through the composite sheet, the projection area is arranged to overlap or superpose with the λ / 4 retardation plate. Therefore, the projection area does not have a section that does not overlap with the λ / 4 retardation plate.

[0020] By arranging an opaque masking layer at least in the projection area, the projection area is arranged to overlap or superpose with the opaque masking layer in a vertical view through the composite sheet or in an orthogonal projection through the composite sheet.

[0021] In a preferred embodiment of the composite sheet according to the invention, the reflective layer is arranged substantially over the entire surface between the outer sheet and the inner sheet. The substantially over-the-entire-surface arrangement of the reflective layer can be understood as an over-the-entire-surface arrangement, or an over-the-entire-surface arrangement minus a surrounding edge area having a width of, for example, 5 mm to 50 mm. The width of the surrounding edge area can be constant or variable.

[0022] In a further preferred embodiment, the reflective layer is arranged between the outer sheet and the inner sheet in an area that is completely within the area where the opaque masking layer is arranged when viewed vertically through the composite sheet.

[0023] As described above, the reflective layer is arranged between the outer sheet and the inner sheet. In a preferred embodiment, the reflective layer is arranged between the inner sheet and the at least one thermoplastic intermediate layer. In a further preferred embodiment, the reflective layer is arranged between the outer sheet and the at least one thermoplastic intermediate layer. In an embodiment where the composite sheet has at least two thermoplastic intermediate layers, the reflective layer can be arranged between the inner sheet and the at least two thermoplastic intermediate layers, or between the outer sheet and the at least two thermoplastic intermediate layers, or in particular between two of the at least two thermoplastic intermediate layers.

[0024] Preferably, the adhesive layer is a thermoplastic polymer layer or an optically clear adhesive (OCA).

[0025] Suitable optically clear adhesives, so-called optically clear adhesives (OCA), are known to those skilled in the art.

[0026] The adhesive layer configured as a thermoplastic polymer layer comprises at least one thermoplastic polymer, preferably ethylene vinyl acetate (EVA), polyvinyl butyral (PVB) or polyurethane (PU) or a mixture or copolymer or derivative thereof, particularly preferably PVB. The thermoplastic polymer layer is typically constructed from a thermoplastic film (bonding film). The thickness of the thermoplastic polymer layer is preferably 0.2 mm to 2 mm, particularly preferably 0.3 mm to 1 mm, for example 760 μm (micrometers). The thermoplastic polymer layer can be constructed from a single film or also from more than one film.

[0027] The opaque masking layer is preferably a peripheral, i.e., frame-shaped, masking layer, which is thus arranged in the surrounding edge area. The peripheral opaque masking layer additionally serves as UV protection for the mounting adhesive of the composite sheet.

[0028] Particularly preferred is an embodiment in which the projection area is arranged adjacent to the lower edge of the composite sheet. Here, the projection area can be arranged either directly adjacent to the lower edge or indirectly adjacent to the lower edge. Indirect adjacency can be understood as that the projection area is not directly adjacent to the lower edge, but is arranged at a distance from the lower edge, for example, a few centimeters, for example, 1 cm to 10 cm, preferably 1 cm to 5 cm.

[0029] Since, when vertically looking through the composite sheet, the projection area is completely within the area of the composite sheet where the λ / 4 retardation plate is arranged, and the λ / 4 retardation plate is arranged in an area of the composite sheet that is completely within the area where the opaque masking layer is arranged when vertically looking through the composite sheet, the opaque masking layer is also preferably arranged at least in the area adjacent to the lower edge of the composite sheet.

[0030] In a preferred embodiment of the composite sheet according to the invention, the opaque masking layer is arranged at least partially in the surrounding edge area and particularly has a greater width in the section overlapping with the projection area than in a section different from this section.

[0031] The opaque masking layer in the sense of the present invention is a layer that prevents seeing through the composite sheet. Here, the transmittance of the light in the visible spectrum passing through the opaque masking layer is at most 10%, preferably at most 5%, particularly preferably at most 2%, very particularly preferably at most 1%, especially at most 0.1%. The opaque masking layer is preferably black.

[0032] The opaque masking layer is preferably a coating composed of one or more layers. However, alternatively, the opaque masking layer can also be an opaque element inserted into the composite sheet, such as a film. According to a preferred design of the composite sheet, the opaque masking layer consists of a single layer. This has the advantage of particularly simple and low-cost manufacturing of the composite sheet because only a single layer for the opaque masking layer needs to be constructed.

[0033] The opaque masking layer is in particular an opaque masking print made of a dark color, preferably black enamel.

[0034] The opaque masking layer configured as an opaque masking print can be constructed over the entire surface. The masking print can also be at least sectionally configured to be translucent, for example, configured as a dot grid, a strip grid, or a square grid. Alternatively, the masking print can also have a gradient, for example, from an opaque covering to a translucent covering. Preferably, the masking layer configured as an opaque masking print is constructed over the entire surface at least in the projection area.

[0035] In a preferred embodiment, the opaque masking layer is configured as an opaque masking print on the inner chamber side surface of the outer sheet.

[0036] In one embodiment, the opaque masking layer is configured as an opaque colored region of the at least one thermoplastic intermediate layer.

[0037] In one embodiment, the composite sheet has a thermoplastic intermediate layer that is integrally formed and colored opaque in a region. In a further embodiment, the composite sheet has at least two thermoplastic intermediate layers, and one of the at least two thermoplastic intermediate layers is configured to be integral and colored opaque in a region.

[0038] An opaque masking layer configured as an opaque colored region of the thermoplastic intermediate layer can also be achieved by using a thermoplastic intermediate layer composed of an opaque thermoplastic film and a transparent thermoplastic film. The opaque thermoplastic film and the transparent thermoplastic film are preferably arranged offset from each other such that the two films do not overlap when looking through the composite sheet. The transparent and opaque films are made of the same plastic or preferably contain the same plastic. The materials (based on which the opaque film and the transparent film can be constructed) are those materials that are also described for the at least one thermoplastic intermediate layer. The opaque film is preferably a colored film, which can have different colors, in particular black.

[0039] From the perspective of a vehicle passenger, the reflective layer is at least partially spatially arranged in front of the opaque masking layer when looking through the inner sheet. Thereby, the following region of the composite sheet functions opaquely, in which region the reflective layer is spatially arranged in front of the opaque masking layer. The reflective layer is preferably transparent in the region in front of the opaque masking layer, but can also be opaque per se. The expression "when looking through the composite sheet" means observing through the composite sheet starting from the inner chamber side surface of the inner sheet. In the sense of the present invention, "spatially in front" means that the reflective layer is arranged spatially further away from the outer side surface of the outer sheet compared to the opaque masking layer.

[0040] The composite sheet according to the invention can optionally have an additional opaque masking print on the inner chamber side surface of the outer sheet, on the outer side surface of the inner sheet, or on the inner chamber side surface of the inner sheet, provided that the additional opaque masking print is arranged in a region outside the main viewing area and outside the projection area.

[0041] The reflective layer is preferably configured as a reflective coating or a reflective film.

[0042] In a preferred embodiment, the reflective layer is configured as a reflective coating on the outer side surface of the inner sheet.

[0043] In a further preferred embodiment, the reflective layer is configured as a reflective coating on the surface of the inner chamber side of the outer sheet body, provided that the opaque masking layer is spatially arranged behind the reflective layer when looking through the composite sheet body from the surface of the inner chamber side of the inner sheet body.

[0044] The reflective layer can also be configured as a reflective coating of a thermoplastic intermediate layer.

[0045] The reflective layer preferably comprises at least one metal or a mixture thereof selected from the group consisting of aluminum, tin, titanium, copper, chromium, cobalt, iron, manganese, zirconium, cerium, yttrium, silver, gold, platinum, and palladium.

[0046] In a preferred embodiment of the present invention, the reflective layer is a reflective coating comprising a thin layer stack, i.e., a sequence of thin single-layer films. The thin layer stack contains one or more silver-based conductive layers. The silver-based conductive layer imparts the basic reflective properties as well as infrared reflection and conductivity to the reflective coating. The conductive layer is constructed based on silver. The conductive layer preferably contains at least 90 wt% silver, particularly preferably at least 99 wt% silver, and very particularly preferably at least 99.9 wt% silver. The silver layer can have dopants, such as palladium, gold, copper, or aluminum. The silver-based material is particularly suitable for reflecting p-polarized light. The coating has a thickness of 5 μm to 50 μm, and preferably 8 μm to 25 μm.

[0047] The reflective layer can also be configured as a reflective, coated, or uncoated film. The reflective layer can be a carrier film with a reflective coating or an uncoated reflective polymer film. The reflective coating preferably comprises at least one metal-based layer and / or a sequence of dielectric layers with alternating refractive indices. The metal-based layer preferably contains and / or consists of silver and / or aluminum. The dielectric layer can be constructed, for example, based on silicon nitride, zinc oxide, tin zinc oxide, silicon metal mixed nitride such as silicon zirconium nitride, zirconium oxide, niobium oxide, hafnium oxide, tantalum oxide, tungsten oxide, or silicon carbide. The oxides and nitrides can be deposited stoichiometrically, sub-stoichiometrically, or super-stoichiometrically. They can have dopants, such as aluminum, zirconium, titanium, or boron. The uncoated reflective polymer film preferably comprises or consists of a dielectric polymer layer. The dielectric polymer layer preferably contains polyethylene terephthalate (PET). If the reflective layer is configured as a reflective film, the reflective layer preferably has a thickness of from 30 μm to 300 μm, particularly preferably from 50 μm to 200 μm, and especially from 100 μm to 150 μm.

[0048] If the reflective layer is configured as a reflective coating, the reflective layer is preferably applied to the surface on the inner chamber side of the outer sheet body or to the outer surface of the inner sheet body by physical vapor deposition (PVD), particularly preferably by cathodic sputtering ("sputtering") and very particularly preferably by magnetron-supported cathodic sputtering ("magnetron sputtering"). In principle, the coating can also be applied, for example, by means of chemical vapor deposition (CVD), plasma-enhanced chemical vapor deposition (PECVD), by evaporation or by atomic layer deposition (ALD).

[0049] If a coated reflective film is involved, CVD or PVD coating methods can likewise be used for manufacturing.

[0050] According to a further preferred embodiment of the composite sheet body according to the invention, the reflective layer is configured as a reflective coated carrier film or an uncoated polymer film and is preferably arranged between two thermoplastic intermediate layers. The advantage of this arrangement is that the reflective layer does not have to be applied to the outer or inner sheet body by means of thin-film technology (such as CVD and PVD). Thereby, a reflective layer with additional advantageous functions (such as a more uniform reflection of light on the reflective layer) is used.

[0051] The reflective layer can also be configured as a film based on polyethylene terephthalate (PET), which is coated with a copolymer layer stack based on PET and / or polyethylene naphthalate (PEN). The coating is preferably applied to the surface on the inner chamber side, that is, on the surface facing the vehicle interior. Such a film is particularly suitable for reflecting p-polarized light. Suitable reflective films are described, for example, in US 5,882,774 A.

[0052] As described above, in a preferred embodiment, the reflective layer has at least one silver-based conductive layer. The conductive layer preferably contains at least 90 wt% silver, particularly preferably at least 99 wt% silver, and very particularly preferably at least 99.9 wt% silver. The silver layer can have dopants, such as palladium, gold, copper or aluminum. The thickness of the silver layer is typically from 5 nm to 20 nm.

[0053] A dielectric layer or layer sequence is typically arranged above and below the conductive layer. If the reflective coating comprises a plurality of conductive layers, preferably each conductive layer is respectively arranged between two typical dielectric layers or layer sequences such that a dielectric layer or layer sequence is respectively arranged between adjacent conductive layers. Thus, the reflective layer is preferably a thin film stack having n conductive layers and (n + 1) dielectric layers or layer sequences, where n is a natural number, and where a conductive layer and a dielectric layer or layer sequence respectively follow alternately on the lower dielectric layer or layer sequence. Such a reflective layer is referred to as a sun protection coating and a heatable coating. Through the at least one conductive layer, the reflective layer has the property of reflecting IR, so that the reflective layer acts as a sun protection coating, which reduces the heating of the vehicle interior by reflecting thermal radiation. When the reflective layer is electrically contacted such that a current flows through the reflective layer, the current heats the reflective layer, and the reflective layer can also be used as a heating coating.

[0054] Common dielectric layers of such thin film stacks are, for example:

[0055] - An antireflection layer that reduces the reflection of visible light and thus improves the transparency of the coated sheet, for example based on silicon nitride, silicon-metal mixed nitrides such as zirconium silicon nitride, titanium oxide, aluminum nitride or tin oxide having a layer thickness of, for example, 10 nm to 100 nm;

[0056] - An adaptation layer that improves the crystallinity of the conductive layer, for example based on zinc oxide (ZnO) having a layer thickness of, for example, 3 nm to 20 nm;

[0057] - A smoothing layer that improves the surface structure for the layer thereon, for example an amorphous oxide based on tin, silicon, titanium, zirconium, hafnium, zinc, gallium and / or indium, in particular a tin-zinc mixed oxide (ZnSnO) having a layer thickness of, for example, 3 nm to 20 nm.

[0058] Due to the at least one conductive layer, such a reflective layer has reflective properties in the visible spectral range, and such reflective properties always occur to some extent with respect to p-polarized radiation. By suitably selecting the layer thickness, in particular the dielectric layer sequence, it is possible to optimize, for example, the reflection with respect to p-polarized radiation in a targeted manner.

[0059] In addition to the conductive layer and the dielectric layer, the reflective layer may also include a barrier layer that protects the conductive layer from degradation. The barrier layer is typically a very thin metal-containing layer based on niobium, titanium, nickel, chromium and / or an alloy having a layer thickness of, for example, 0.1 nm to 2 nm.

[0060] In a particularly preferred embodiment, the reflective layer has exactly one conductive layer based on silver.

[0061] In a very particularly preferred embodiment, the reflective layer has exactly one silver-based conductive layer and a lower dielectric layer or layer sequence is arranged below the conductive layer, which has a refractive index of at least 1.9, and an upper dielectric layer or layer sequence is arranged above the conductive layer, which has a refractive index of at least 1.9, and the ratio of the optical thickness of the upper dielectric layer or layer sequence to the optical thickness of the lower dielectric layer or layer sequence is at least 1.7. Thus, the reflective layer can be constructed as described, for example, in WO2021 / 104800A1.

[0062] Within the scope of the present invention, the refractive index is in principle given based on a wavelength of 550 nm. The method for determining the refractive index is known to those skilled in the art. The refractive index given within the scope of the present invention can be determined, for example, by means of ellipsometry, where commercially available ellipsometers can be used. The description of the layer thickness or thickness, unless otherwise stated, relates to the geometric thickness of the layer.

[0063] If the first layer is arranged above the second layer, this means in the sense of the present invention that the first layer is arranged further away from the substrate to which the coating is applied than the second layer. If the first layer is arranged below the second layer, this means in the sense of the present invention that the second layer is arranged further away from the substrate than the first layer.

[0064] If a layer is constructed from one material, then the layer consists mostly of this material, in particular consists essentially of this material except for possible impurities or doping. The oxides and nitrides can be deposited stoichiometrically, sub-stoichiometrically or super-stoichiometrically (although the stoichiometric sum formula is given for better understanding). They can have doping, such as aluminum, zirconium, titanium or boron.

[0065] The composite sheet can additionally include a coating that is constructed 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.

[0066] Suitable protective coatings or anti-reflection coatings are known to those skilled in the art.

[0067] The outer sheet and the inner sheet are preferably made of glass, in particular of soda-lime glass, which is common for sheets. But these sheets can in principle also be made of other types of glass (such as borosilicate glass, quartz glass, aluminosilicate glass) or transparent plastics (such as polymethyl methacrylate or polycarbonate). The thicknesses of the outer sheet and the inner sheet can vary greatly. Sheets having a thickness in the range from 0.8 mm to 5 mm, preferably from 1.4 mm to 2.5 mm, for example sheets having a standard thickness of 1.6 mm or 2.1 mm, are preferably used.

[0068] In a preferred embodiment, the inner sheet has a thickness of at most 1.6 mm, particularly preferably at most 1.4 mm, and very particularly preferably at most 1.1 mm.

[0069] The outer sheet, the inner sheet and the at least one thermoplastic interlayer can be transparent and colorless, but can also be dyed or colored. In a preferred design, the total transmittance through the windshield (together with the reflective coating) is greater than 70% (light type A) in the main perspective area. The term total transmittance relates to the method for checking the light transmittance of vehicle sheets as determined by ECE-R 43, Appendix 3, Section 9.1. The outer sheet and the inner sheet can be not pre-tensioned, partially pre-tensioned or pre-tensioned independently of each other. If at least one sheet should have pre-tension, this can be thermal pre-tension or chemical pre-tension.

[0070] Preferably, the inner sheet is not colored or dyed.

[0071] The composite sheet is preferably bent in one or more directions in space, as is common for vehicle sheets, where the typical radius of curvature is in the range of about 10 cm to about 40 m. However, for example when the composite sheet is provided as a sheet for a bus, a train or a tractor, the composite sheet can also be flat.

[0072] The at least one thermoplastic interlayer comprises at least one thermoplastic polymer, preferably ethylene vinyl acetate (EVA), polyvinyl butyral (PVB) or polyurethane (PU) or a mixture or copolymer or derivative thereof, particularly preferably PVB. The thickness of the interlayer is preferably 0.2 mm to 2 mm, particularly preferably 0.3 mm to 1 mm. The at least one thermoplastic interlayer can also be a film with functional properties, for example a film with acoustic attenuation properties. Preferably, the at least one thermoplastic interlayer has a constant thickness except for possible surface roughnesses common in the art, that is, it does not have a wedge-shaped cross-section.

[0073] A retarder, also called a retardation layer or wave plate, is an optical element that produces a phase shift of transmitted light. The desired retardation is achieved by changing the thickness of the retarder and its orientation in the optical path. A phase shift of 90° refers to a λ / 4 plate, a quarter-wave plate or also a circular polarizer.

[0074] Suitable λ / 4 retarders are known to those skilled in the art.

[0075] The λ / 4 retarder is made of a birefringent material. Birefringent materials have slightly different refractive indices for light.

[0076] In a preferred embodiment, the λ / 4 retardation plate is embodied as a polymer retardation plate. λ / 4 retardation plates are commercially available in the form of birefringent plastic films. The polymer components are very well adapted to the possible three-dimensional bending of the sheet and can be integrated into the composite sheet in a simple manner and method.

[0077] In a further preferred embodiment, the λ / 4 retardation plate is embodied as a retardation plate made of crystalline quartz or sapphire.

[0078] The λ / 4 retardation plate is used to obtain circularly polarized light from linearly polarized light and vice versa. Here, the polarization of the incident radiation needs to be at 45° to the optical axis of the plate. The λ / 4 retardation plate has a design wavelength of approximately 560 nm.

[0079] The composite sheet according to the invention can be manufactured by a method comprising at least the following steps:

[0080] a) Providing a composite body having a projection area, a main perspective area, an upper edge, a lower edge and two lateral sheet edges, the composite body comprising an outer sheet having an outer surface and an inner chamber side surface, at least one thermoplastic intermediate layer, a reflective layer, an opaque masking layer and an inner sheet having an outer surface and an inner chamber side surface, wherein the outer sheet has an outer surface facing away from the outer side of the at least one thermoplastic intermediate layer and an inner chamber side surface facing the at least one thermoplastic intermediate layer, and the inner sheet has an outer surface facing the outer side of the at least one thermoplastic intermediate layer and an inner chamber side surface facing away from the at least one thermoplastic intermediate layer, the projection area being arranged outside the main perspective area, the reflective layer being arranged at least in the projection area between the outer sheet and the inner sheet, the opaque masking layer being arranged at least in the projection area between the outer sheet and the inner sheet, and being spatially arranged behind the reflective layer when looking through the composite body from the inner chamber side surface of the inner sheet;

[0081] b) Providing a λ / 4 retardation plate and an adhesive layer;

[0082] c) Connecting the λ / 4 retardation plate to the inner chamber side surface of the inner sheet of the composite body via the adhesive layer to form a composite sheet having a projection area, a main perspective area, an upper edge, a lower edge and two lateral sheet edges, such that the λ / 4 retardation plate is arranged in the area of the composite sheet which, when looking vertically through the composite sheet, is completely within the area where the opaque masking layer is arranged, and the projection area is completely within the area where the λ / 4 retardation plate is arranged when looking vertically through the composite sheet.

[0083] The composite sheet according to the invention can also be manufactured by a method comprising at least the following steps:

[0084] a) Provide a stacking sequence having a projection area, a main perspective area, an upper edge, a lower edge, and two lateral sheet edges, the stacking sequence including an outer sheet having an outer surface and an inner chamber side surface, at least one thermoplastic intermediate layer, a reflective layer, an opaque masking layer, an inner sheet having an outer surface and an inner chamber side surface, an adhesive layer, and a λ / 4 retardation plate, wherein the outer sheet has an outer surface facing away from the at least one thermoplastic intermediate layer and an inner chamber side surface facing the at least one thermoplastic intermediate layer, and the inner sheet has an outer surface facing the at least one thermoplastic intermediate layer and an inner chamber side surface facing away from the at least one thermoplastic intermediate layer, the projection area is arranged outside the main perspective area, the reflective layer is arranged between the outer sheet and the inner sheet at least in the projection area, the opaque masking layer is arranged between the outer sheet and the inner sheet at least in the projection area and is spatially arranged behind the reflective layer when looking through the composite sheet from the inner chamber side surface of the inner sheet, the λ / 4 retardation plate is arranged in a region of the stacking sequence that is completely within the region where the opaque masking layer is arranged when looking vertically through the stacking sequence, the adhesive layer is arranged between the λ / 4 retardation plate and the inner chamber side surface of the inner sheet and is configured as a thermoplastic polymer layer, and the projection area is completely within the region of the stacking sequence where the λ / 4 retardation plate is arranged when looking vertically through the stacking sequence;

[0085] b) Connect the stacking sequence into a composite sheet having a projection area, a main perspective area, an upper edge, a lower edge, and two lateral sheet edges by lamination.

[0086] The invention also relates to a projection assembly including the composite sheet according to the invention and an image display device that points to the projection area of the composite sheet. The image display device is arranged such that the inner chamber side surface of the inner sheet is the surface of the inner sheet closest to the image display device.

[0087] Therefore, the invention also relates to a projection assembly including:

[0088] - a composite sheet having a projection area, a main perspective area, an upper edge, a lower edge, and two lateral sheet edges, the composite sheet at least including an outer sheet, at least one thermoplastic intermediate layer, a reflective layer, an opaque masking layer, an inner sheet, an adhesive layer, and a λ / 4 retardation plate,

[0089] wherein,

[0090] The outer sheet has an outer surface facing away from the at least one thermoplastic intermediate layer and a surface facing the inner chamber side of the at least one thermoplastic intermediate layer, and the inner sheet has an outer surface facing the at least one thermoplastic intermediate layer and a surface facing away from the inner chamber side of the at least one thermoplastic intermediate layer.

[0091] The projection area is arranged outside the main perspective area.

[0092] The reflective layer is arranged between the outer sheet and the inner sheet at least in the projection area.

[0093] The opaque masking layer is arranged between the outer sheet and the inner sheet at least in the projection area and is spatially arranged behind the reflective layer when looking through the composite sheet from the surface of the inner chamber side of the inner sheet.

[0094] The λ / 4 retardation plate is connected to the surface of the inner chamber side of the inner sheet through an adhesive layer and is arranged in the following area of the composite sheet, which area is completely within the area where the opaque masking layer is arranged when looking vertically through the composite sheet, and

[0095] The projection area is completely within the area of the composite sheet where the λ / 4 retardation plate is arranged when looking vertically through the composite sheet.

[0096] - and an image display device, which is directed at the projection area and is arranged such that the surface of the inner chamber side of the inner sheet is the surface of the inner sheet closest to the image display device.

[0097] In a preferred embodiment of the projection assembly according to the present invention, the image display device emits s-polarized light. This light first hits the λ / 4 retardation plate and is converted into circularly polarized light by the λ / 4 retardation plate and then hits the reflective layer. The circularly polarized light is reflected by the reflective layer, wherein the direction of rotation changes. Before the reflected circularly polarized light leaves the composite sheet, it passes through the λ / 4 retardation plate again and is converted into p-polarized light. The p-polarized light can also be well perceived by an observer wearing polarization-selective sunglasses. This is an advantage of the projection assembly according to the present invention, that is, in the case of using an image display device that emits s-polarized light, p-polarized light reaches the observer.

[0098] In a further preferred embodiment of the projection assembly according to the present invention, the image display device emits circularly polarized light. This circularly polarized light first hits the λ / 4 retardation plate and is converted into p-polarized light by the λ / 4 retardation plate and then hits the reflective layer. The p-polarized light is reflected by the reflective layer. Before the reflected p-polarized light leaves the composite sheet, it passes through the λ / 4 retardation plate again and is converted into circularly polarized light. The circularly polarized light can also be well perceived by an observer wearing polarization-selective sunglasses.

[0099] The aforementioned preferred design of the composite sheet according to the invention correspondingly also applies to the projection assembly according to the invention comprising the composite sheet according to the invention and an image display device, and vice versa.

[0100] The term p-polarized light refers to light in the visible spectrum having p-polarization. Here, the polarization direction is observed with respect to the plane of incidence of the radiation on the composite sheet. Radiation in which the electric field oscillates within the plane of incidence is called p-polarized radiation. Radiation in which the electric field oscillates perpendicular to the plane of incidence is called s-polarized radiation. The plane of incidence is formed by the incident vector and the surface normal at the geometric center of the irradiated area of the composite sheet. In other words, polarization is determined at a point in the area irradiated by the light source, preferably at the geometric center of the irradiated area, i.e., in particular the components of p-polarized and s-polarized radiation. Since the composite sheet can be bent (for example, when the composite sheet is configured as a windshield), this has an impact on the plane of incidence of the radiation, and slightly deviated polarization components may occur in other areas, which are inevitable for physical reasons.

[0101] Within the scope of the present application, the area that can be irradiated by the image display device when the composite sheet is applied in a projection assembly comprising the composite sheet and an image display device is called the projection area. This area includes the following area of the composite sheet, through which the light reflected by the reflective layer is reflected to the observer. The area (through which the vehicle driver or observer mainly observes through the composite sheet) is called the main perspective area within the scope of the present application.

[0102] "Transparent" in the sense of the present invention means that the total transmittance of the composite sheet complies with the legal regulations for windshields and preferably has a transmittance of greater than 50%, particularly greater than 60%, for example greater than 70%, for visible light. Correspondingly, "opaque" means a light transmittance of less than 10%, preferably less than 5%, and in particular 0%.

[0103] According to a preferred design of the projection assembly according to the invention, the image display device (which can be, for example, a projector or preferably a display) can be configured as a liquid crystal (LCD) display, a thin film transistor (TFT) display, a light emitting diode (LED) display, an organic light emitting diode (OLED) display, an electroluminescent (EL) display, a microLED display, etc., preferably configured as an LCD display. Energy-intensive projectors, such as those mostly used in head-up display applications, are not necessarily required. The mentioned display variants and other similar energy-saving image display devices are sufficient. This results in reduced energy consumption.

[0104] Preferably, the radiation of the image display device impinges on the composite sheet at an incident angle of 55° to 80°, particularly preferably 62° to 77°.

[0105] The use of the composite sheet according to the invention as a vehicle sheet in a vehicle for land, air or water transportation, in particular in a motor vehicle and in particular as a windshield for a head-up display. Description of the Drawings

[0106] The invention will be explained in more detail with the aid of the drawings and embodiments. The drawings are schematic representations and not to scale. The drawings do not limit the invention in any way. In the drawings:

[0107] Figure 1 is a top view of an embodiment of the composite sheet according to the invention,

[0108] Figure 2 is Figure 1 a cross-section of the embodiment shown in

[0109] Figure 3 is a cross-section through a further embodiment of the composite sheet according to the invention,

[0110] Figure 4 is a cross-section through a further embodiment of the composite sheet according to the invention,

[0111] Figure 5 is a cross-section through a further embodiment of the composite sheet according to the invention,

[0112] Figure 6 is a cross-section through a further embodiment of the composite sheet according to the invention,

[0113] Figure 7 is a cross-section through a further embodiment of the composite sheet according to the invention,

[0114] Figure 8 is a cross-section through a further embodiment of the composite sheet according to the invention,

[0115] Figure 9 is a cross-section through a further embodiment of the composite sheet according to the invention,

[0116] Figure 10 is a cross-section through a further embodiment of the composite sheet according to the invention,

[0117] Figure 11 is a cross-section through a further embodiment of the composite sheet according to the invention,

[0118] Figure 12 is a cross-section through a further embodiment of the composite sheet according to the invention,

[0119] Figure 13 is a cross-section of a projection assembly according to the present invention,

[0120] Figure 14 is a cross-section of an embodiment of a projection assembly according to the present invention,

[0121] Figure 15 is a cross-section of an embodiment of a projection assembly according to the present invention,

[0122] Figure 16 is an enlarged intercepted portion of a cross-section of an embodiment of a projection assembly according to the present invention, and

[0123] Figure 17 is an enlarged intercepted portion of a cross-section of another embodiment of a projection assembly according to the present invention. Detailed Embodiment

[0124] Figure 1 shows a top view of an embodiment of the composite sheet 1 according to the present invention, and Figure 2 shows a cross-section of the composite sheet 1 along the cutting line X-X' shown in Figure 1 The composite sheet 1 shown in has an upper edge O, a lower edge U, and two side edges K. In addition, Figure 1 and Figure 2 The composite sheet 1 shown in has a main perspective area H and a projection area B. In Figure 1 The main perspective area H and the projection area B of the composite sheet 1 are drawn. In Figure 1 and Figure 2 The composite sheet 1 shown in includes an outer sheet 2 having an outer surface I and an inner chamber side surface II, an inner sheet 6 having an outer surface III and an inner chamber side surface IV, a thermoplastic intermediate layer 3, a reflective layer 4, an opaque masking layer 5, an adhesive layer 7, and a λ / 4 retardation plate 8. The thermoplastic intermediate layer 3 is disposed between the outer sheet 2 and the inner sheet 6. The outer surface I of the outer sheet 2 faces away from the thermoplastic intermediate layer 3, the inner chamber side surface II of the outer sheet 2 faces the thermoplastic intermediate layer 3, the outer surface III of the inner sheet 6 faces the thermoplastic intermediate layer 3, and the inner chamber side surface IV of the inner sheet 6 faces away from the thermoplastic intermediate layer 3. The outer sheet 2, the thermoplastic intermediate layer 3, the reflective layer 4, and the inner sheet 6 are arranged in full-surface superposition. The projection area B is arranged outside the main perspective area H. In Figure 1 and Figure 2 In the embodiment shown, the projection area B is arranged adjacent to the lower edge U. The opaque masking layer 5 is disposed at least in the projection area B between the outer sheet 2 and the inner sheet 6, and is spatially disposed behind the reflective layer 4 when viewed through the composite sheet 1 from the inner chamber side surface IV of the inner sheet 6. In Figure 1 and Figure 2In the embodiment shown, the opaque masking layer 5 is configured as an opaque masking print disposed on the surface II on the inner chamber side of the outer sheet 2 and is disposed in the surrounding edge region, which has a greater width in the section overlapping with the projection region B than in the section different from this section. The λ / 4 retardation plate 8 is connected to the surface IV on the inner chamber side of the inner sheet 6 through the adhesive layer 7 and is disposed in the following region of the composite sheet 1, which region is completely within the region where the opaque masking layer 5 is disposed when vertically looking through the composite sheet 1. The projection region B is completely within the region of the composite sheet 1 where the λ / 4 retardation plate is disposed when vertically looking through the composite sheet 1.

[0125] The thermoplastic interlayer 3 is, for example, an interlayer made of PVB and has a thickness of 0.76 mm. The thermoplastic interlayer 3 has a substantially constant thickness, except for possible surface roughness common in the art - the thermoplastic interlayer is not configured as a so-called wedge film.

[0126] The outer sheet 2 and the inner sheet 6 are made of soda-lime glass, for example. The outer sheet 2 has a thickness of 2.1 mm, for example, and the inner sheet 6 has a thickness of 1.6 mm or 1.1 mm, for example.

[0127] The adhesive layer 7 is, for example, an optically transparent adhesive (OCA). Alternatively, the adhesive layer 7 can also be a thermoplastic polymer layer, for example, a layer made of PVB having a thickness of 0.38 mm, for example.

[0128] In Figure 1 and Figure 2 In the embodiment shown, a reflective layer 4 is applied over the entire surface on the outer side surface III of the inner sheet 6, which reflective layer is configured as a thin film stack including at least one silver-based conductive layer, for example.

[0129] Figure 3 Shows a cross-section of a further embodiment of the composite sheet 1 according to the invention. Figure 3 The embodiment shown in Figure 2 differs from the embodiment shown in

[0130] Figure 4 only in that the reflective layer 4 is only disposed in the following region of the composite sheet 1, which region is completely within the region where the opaque masking layer 5 is disposed when vertically looking through the composite sheet 1. In this embodiment, the reflective layer 4 can be configured as a coating on the outer side surface III of the inner sheet 6 or as a reflective film disposed between the thermoplastic interlayer 3 and the inner sheet 6. Figure 4 The embodiment shown in Figure 2The difference in the embodiment shown is only that the reflective layer 4 is not arranged between the thermoplastic intermediate layer 3 and the inner sheet 6, but between the thermoplastic intermediate layer 3 and the outer sheet 2, provided that the opaque masking layer 5 is spatially arranged behind the reflective layer 4 when looking through the composite sheet 1 from the surface IV on the inner chamber side of the inner sheet 6. The reflective layer 4, which is, for example, configured as a coating on the surface II on the inner chamber side of the outer sheet 2, is thus not directly arranged on the outer sheet 2 in the region where the opaque masking layer 5 is arranged as an opaque masking print on the surface II on the inner chamber side of the outer sheet 2, but on the opaque masking layer 5.

[0131] Figure 5 Shows a cross-section of a further embodiment of the composite sheet 1 according to the invention. Figure 5 The embodiment shown in Figure 4 The difference from the embodiment shown in

[0132] Figure 6 Shows a cross-section of a further embodiment of the composite sheet 1 according to the invention. Figure 6 The embodiment shown in Figure 2 The difference from the embodiment shown in

[0133] Figure 7 Shows a cross-section of a further embodiment of the composite sheet 1 according to the invention. Figure 7 The embodiment shown in Figure 3The difference between the embodiment shown in [reference] is only that the composite sheet 1 has two thermoplastic intermediate layers 3, and the reflective layer 4 is arranged between the two thermoplastic intermediate layers 3. In this embodiment, the reflective layer 4 can be configured as a coating of one of the two thermoplastic intermediate layers or as a reflective film arranged between the two thermoplastic intermediate layers 3.

[0134] Figure 8 Shows a cross-section of a further embodiment of the composite sheet 1 according to the invention. Figure 8 The embodiment shown in [reference] and Figure 2 The difference between the embodiment shown in [reference] is only that the opaque masking layer 5 is not configured as an opaque masking print on the inner chamber side surface II of the outer sheet 2, but as an opaque colored area of the thermoplastic intermediate layer 3.

[0135] In the region adjacent to the upper edge O, the thermoplastic intermediate layer 3 alternatively also has no coloring and optionally an opaque masking print is applied to the inner chamber side surface II of the outer sheet 2, the outer side surface III of the inner sheet 6 or the inner chamber side surface IV of the inner sheet 6.

[0136] Figure 9 Shows a cross-section of a further embodiment of the composite sheet 1 according to the invention. Figure 9 The embodiment shown in [reference] and Figure 8 The difference between the embodiment shown in [reference] is only that the reflective layer 4 is only arranged in the region of the composite sheet 1 which, when viewed vertically through the composite sheet 1, is completely within the region where the opaque masking layer 5 is arranged. In this embodiment, the reflective layer 4 can be configured as a coating of the outer side surface III of the inner sheet 6 or as a reflective film arranged between the thermoplastic intermediate layer 3 and the inner sheet 6.

[0137] Figure 10 Shows a cross-section of a further embodiment of the composite sheet 1 according to the invention. Figure 10 The embodiment shown in [reference] and Figure 6 The difference between the embodiment shown in [reference] is only that the opaque masking layer 5 is not configured as an opaque masking print on the inner chamber side surface II of the outer sheet 2, but as an opaque colored area of the thermoplastic intermediate layer 3 closest to the outer sheet 2.

[0138] In the region adjacent to the upper edge O, the thermoplastic intermediate layer 3 closest to the outer sheet 2 alternatively also has no coloring and optionally an opaque masking print is applied to the inner chamber side surface II of the outer sheet 2, the outer side surface III of the inner sheet 6 or the inner chamber side surface IV of the inner sheet 6.

[0139] Figure 11Shows a cross-section of a further embodiment of the composite sheet 1 according to the invention. Figure 11 The embodiment shown in Figure 10 differs from the embodiment shown in

[0140] Figure 12 only in that the reflective layer 4 is arranged only in the region of the composite sheet 1 which, when viewed vertically through the composite sheet 1, lies entirely within the region in which the opaque masking layer 5 is arranged. In this embodiment, the reflective layer 4 can be configured as a coating of one of the two thermoplastic intermediate layers 3 or as a reflective film arranged between the two thermoplastic intermediate layers 3. Figure 12 The embodiment shown in Figure 2 differs from the embodiment shown in

[0141] Figure 13 only in that a coating 9 is arranged on the surface of the λ / 4 retardation plate 8 facing away from the adhesive layer 7, which coating is configured as a protective coating or an anti-reflection coating. Figure 13 The projection assembly 100 shown in Figures 2 to 12 comprises a composite sheet 1 according to the invention and an image display device 10. The composite sheet 1 according to the invention is constructed, for example, as shown in

[0142] Figure 14 Shows a cross-section through an embodiment of a projection assembly 100 according to the invention, which projection assembly comprises a composite sheet 1 and an image display device 10. The composite sheet 1 is constructed as shown in Figure 2 The embodiment shown in Figure 14 The composite sheet 1 of the projection assembly 100 has an upper edge O, a lower edge U and two side edges K. Furthermore, in Figure 14 the main perspective region H and the projection region B of the composite sheet 1 are drawn. In Figure 14In the embodiment of the projection assembly 100 shown, the composite sheet 1 includes an outer sheet 2 having an outer surface I and an inner chamber side surface II, an inner sheet 6 having an outer surface III and an inner chamber side surface IV, a thermoplastic interlayer 3, a reflective layer 4, an opaque masking layer 5, an adhesive layer 7, and a λ / 4 retardation plate 8. The thermoplastic interlayer 3 is disposed between the outer sheet 2 and the inner sheet 6. The outer surface I of the outer sheet 2 faces away from the thermoplastic interlayer 3, and the inner chamber side surface II of the outer sheet 2 faces the thermoplastic interlayer 3. The outer surface III of the inner sheet 6 faces the thermoplastic interlayer, and the inner chamber side surface IV of the inner sheet 6 faces away from the thermoplastic interlayer. The outer sheet 2, the thermoplastic interlayer 3, the reflective layer 4, and the inner sheet 6 are arranged in full-surface overlap. The projection area B is arranged outside the main perspective area H. In Figure 14 In the embodiment shown, the projection area B is arranged adjacent to the lower edge U. The opaque masking layer 5 is disposed at least in the projection area B between the outer sheet 2 and the inner sheet 6 and is spatially disposed behind the reflective layer 4 when viewed through the composite sheet 1 from the inner chamber side surface IV of the inner sheet 6. The opaque masking layer 5 is configured as an opaque masking print disposed on the inner chamber side surface II of the outer sheet 2 and is disposed in a surrounding edge area that has a greater width in a section overlapping the projection area B than in a section different from this section. The λ / 4 retardation plate is connected to the inner chamber side surface IV of the inner sheet 6 by the adhesive layer 7 and is disposed in an area of the composite sheet 1 that is completely within the area where the opaque masking layer 5 is disposed when viewed vertically through the composite sheet 1. The projection area B is completely within the area of the composite sheet 1 where the λ / 4 retardation plate 8 is disposed when viewed vertically through the composite sheet 1.

[0143] The thermoplastic interlayer 3 is, for example, an interlayer made of PVB and has a thickness of 0.76 mm. The thermoplastic interlayer 3 has a substantially constant thickness, except for possible surface roughness common in the art - the thermoplastic interlayer is not configured as a so-called wedge film.

[0144] The outer sheet 2 and the inner sheet 6 are made of soda-lime glass, for example. The outer sheet 2 has a thickness of 2.1 mm, for example, and the inner sheet 6 has a thickness of 1.6 mm or 1.1 mm, for example.

[0145] The adhesive layer 7 is, for example, an optically clear adhesive (OCA). Alternatively, the adhesive layer 7 can also be a thermoplastic polymer layer, for example, a layer made of PVB having a thickness of 0.38 mm, for example.

[0146] In Figure 14In the embodiment shown in [reference], a reflective layer 4 is applied over the entire outer surface III of the inner sheet body 6, which is configured, for example, as a thin-film stack including at least one silver-based conductive layer.

[0147] Figure 15 Shows a cross-section of a further embodiment of the projection assembly 100 according to the invention, wherein Figure 15 The embodiment shown in [reference] is different from Figure 14 the embodiment shown in [reference] only in that the reflective layer 4 is arranged only in the region of the composite sheet body 1 which, when viewed vertically through the composite sheet body 1, lies entirely within the region in which the opaque masking layer 5 is arranged. In this embodiment, the reflective layer 4 can be configured as a coating on the outer surface III of the inner sheet body 6 or as a reflective film arranged between the thermoplastic intermediate layer 3 and the inner sheet body 6. Thus, in Figure 15 the embodiment shown in [reference], the composite sheet body 1 is configured as Figure 3 shown in [reference].

[0148] Figure 16 Shows an enlarged cross-sectional portion of a cross-section through an embodiment of the projection assembly 100 according to the invention, which projection assembly includes a composite sheet body 1 and an image display device 10, wherein the optical path of the light emitted by the image display device 10 is shown in more detail. The composite sheet body 1 is configured as shown in Figure 1 and Figure 2 shown in [reference]. The image display device 10 emits s-polarized light. This s-polarized light first strikes the λ / 4 retardation plate 8 and is converted by this λ / 4 retardation plate into circularly polarized light and strikes the reflective layer 4. The circularly polarized light is reflected by the reflective layer 8, wherein the direction of rotation changes. Before the reflected circularly polarized light exits the composite sheet body 1, it passes through the λ / 4 retardation plate 8 again and is converted into p-polarized light. Since only p-polarized light exits the composite sheet body 1, the reflection can be well perceived by an observer wearing polarization-selective sunglasses.

[0149] Figure 17 Shows an enlarged cross-sectional portion of a cross-section through a further embodiment of the projection assembly 100 according to the invention, which projection assembly includes a composite sheet body 1 and an image display device 10, wherein the optical path of the light emitted by the image display device 10 is shown in more detail. The composite sheet body 1 is configured as shown in Figure 1 and Figure 2 shown in [reference]. The image display device 10 emits circularly polarized light. This circularly polarized light first strikes the λ / 4 retardation plate 8 and is converted by this λ / 4 retardation plate into p-polarized light and strikes the reflective layer 4. The p-polarized light is reflected by the reflective layer 4. Before the reflected p-polarized light exits the composite sheet body 1, it passes through the λ / 4 retardation plate 8 again and is converted into circularly polarized light. The circularly polarized light can also be well perceived by an observer wearing polarization-selective sunglasses.

[0150] List of Reference Numerals

[0151] 1 Composite Sheet

[0152] 2 Outer Sheet

[0153] 3 Thermoplastic Intermediate Layer

[0154] 4 Reflective Layer

[0155] 5 Opaque Masking Layer

[0156] 6 Inner Sheet

[0157] 7 Adhesive Layer

[0158] 8 λ / 4 Retardation Plate

[0159] 9 Coating

[0160] 10 Image Display Device

[0161] 100 Projection Assembly

[0162] O Upper Edge

[0163] U Lower Edge

[0164] K Side Edge

[0165] B Projection Area

[0166] H Main Perspective Area

[0167] I Outer Surface of Outer Sheet 2

[0168] II Surface of Outer Sheet 2 on the Inner Chamber Side

[0169] III Outer Surface of Inner Sheet 6

[0170] IV Surface of Inner Sheet 6 on the Inner Chamber Side

[0171] X'-X Section Line

[0172] s s-Polarized Light

[0173] p p-Polarized Light

[0174] c Circularly Polarized Light

Claims

1. A composite sheet (1), the composite sheet having a projection area (B), a main perspective area (H), an upper edge (O), a lower edge (U) and two lateral sheet edges (K), the composite sheet comprising at least an outer sheet (2), at least one thermoplastic intermediate layer (3), a reflective layer (4), an opaque masking layer (5), an inner sheet (6), an adhesive layer (7) and a λ / 4 retardation plate (8), wherein, the outer sheet (2) has an outer surface (I) facing away from the at least one thermoplastic intermediate layer (3) and an inner chamber side surface (II) facing the at least one thermoplastic intermediate layer (3), and the inner sheet (6) has an outer surface (III) facing the at least one thermoplastic intermediate layer (3) and an inner chamber side surface (IV) facing away from the at least one thermoplastic intermediate layer (3), the projection area (B) is arranged outside the main perspective area (H), and the reflective layer (4) is arranged between the outer sheet (2) and the inner sheet (6) at least in the projection area (B), the opaque masking layer (5) is arranged between the outer sheet (2) and the inner sheet (6) at least in the projection area (B), and is spatially arranged behind the reflective layer (4) when looking through the composite sheet (1) from the inner chamber side surface (IV) of the inner sheet (6), the λ / 4 retardation plate (8) is connected to the inner chamber side surface (IV) of the inner sheet (6) by the adhesive layer (7) and is arranged in a region of the composite sheet (1) which is completely within the region where the opaque masking layer (5) is arranged when looking vertically through the composite sheet (1), and the projection area (B) is completely within the region of the composite sheet (1) where the λ / 4 retardation plate (8) is arranged when looking vertically through the composite sheet (1).

2. The composite sheet (1) according to claim 1, wherein, The reflective layer (4) is arranged substantially over the entire surface between the outer sheet (2) and the inner sheet (6).

3. The composite sheet (1) according to claim 1, wherein, The reflective layer (4) is arranged between the outer sheet (2) and the inner sheet (6) in a region of the composite sheet (1) which is completely within the region where the opaque masking layer (5) is arranged when looking vertically through the composite sheet (1).

4. The composite sheet (1) according to any one of claims 1 to 3, wherein, The reflective layer (4) is arranged between the inner sheet (6) and the at least one thermoplastic intermediate layer (3) or between the outer sheet (2) and the at least one thermoplastic intermediate layer (3); or, the composite sheet (1) comprises at least two thermoplastic intermediate layers (3), and the reflective layer (4) is arranged between two of the thermoplastic intermediate layers among the respective thermoplastic intermediate layers (3).

5. The composite sheet (1) according to any one of claims 1 to 4, wherein, The adhesive layer (7) is a thermoplastic polymer layer or an optically transparent adhesive.

6. The composite sheet (1) according to any one of claims 1 to 5, wherein, The projection area (B) is arranged adjacent to the lower edge (U) of the composite sheet (1).

7. The composite sheet (1) according to any one of claims 1 to 6, wherein, The opaque masking layer (5) is arranged at least partially in the circumferential edge region and, in particular, has a greater width in the section that coincides with the projection region (B) than in sections that are different from this section.

8. The composite sheet (1) according to any one of claims 1 to 7, wherein, The opaque masking layer (5) is configured as an opaque masking print on the inner chamber side surface (II) of the outer sheet body (2) or as an opaque colored region of the at least one thermoplastic intermediate layer (3).

9. The composite sheet (1) according to any one of claims 1 to 8, wherein, The reflective layer (4) is configured as a reflective coating or a reflective film.

10. The composite sheet (1) according to any one of claims 1 to 9, further comprising a coating (9) configured as a protective coating or an anti-reflection coating and arranged on the surface of the λ / 4 retardation plate (8) facing away from the adhesive layer (7).

11. A projection assembly (100) comprising at least: - the composite sheet (1) according to any one of claims 1 to 10, and - an image display device (10) that points to the projection region (B) and is arranged such that the inner chamber side surface (IV) of the inner sheet body (6) is the surface of the inner sheet body (6) closest to the image display device (10).

12. The projection assembly (100) according to claim 11, wherein, The image display device (10) is a projector or a display, preferably an LCD display, an LED display, a microLED display, an OLED display or an electroluminescent display, particularly preferably an LCD display, and the radiation preferably impinges on the composite sheet (1) at an incident angle of 55° to 80°, particularly preferably 62° to 77°.

13. The projection assembly (100) according to claim 11 or 12, wherein, The image display device (10) emits s-polarized light.

14. The projection assembly (100) according to claim 11 or 12, wherein, The image display device (10) emits circularly polarized light.

15. Use of the composite sheet (1) according to any one of claims 1 to 10 as a vehicle sheet in a vehicle for land, air or water transportation, in particular in a motor vehicle and in particular as a windshield for a head-up display.

Images