DISPLAY SYSTEM FOR A VEHICLE WITH TWO DIFFERENT OPERATING MODES

Description

[0001] The invention relates to a display system for a vehicle and a vehicle equipped therewith.

[0002] Windshields for vehicles, especially passenger cars, are designed as laminated glass (laminated safety glass), consisting of an outer pane and an inner pane laminated together with a thermoplastic interlayer. They typically feature an opaque masking area, which forms a continuous border and surrounds a central viewing area. The primary purpose of this opaque masking area is to protect the adhesive used to bond the windshield to the vehicle body from UV radiation. If the windshield is equipped with electrical functions (such as a heating function), the necessary electrical connections can also be concealed within the masking area. The masking area is typically created by a black printed overprint on the surface of the outer pane facing the interlayer.

[0003] It has been proposed to use the opaque masking area as a display surface for a display system. For this purpose, the display area is coated with a reflective layer and illuminated by an imaging unit, such as a screen or projector. The image projected onto the reflective layer of the imaging unit is perceptible to a user, particularly the driver, as a display image. Examples include DE102009020824A1, WO2022073894A1, and WO2022073860A1.

[0004] In this way, displays for the driver, which were previously located on the dashboard, can be projected directly onto the windshield. This is not only aesthetically pleasing but also improves driving safety, as the driver has to take their eyes off the road less to read the display. Examples of such displays include vehicle speed, time, engine speed, navigation system information, speed limit information (traffic sign recognition), a rear-view camera image, and various vehicle status indicators.

[0005] In advanced training courses, such a display system can also be provided for the passenger. For example, entertainment content can be displayed on the windshield. However, there is a risk that the driver will be disturbed or distracted by the passenger's display system, which impairs road safety. Therefore, there is a need for display systems of the type mentioned above that show information to the passenger without distracting the driver.

[0006] From WO2019034557A1, a screen is known that can be operated in two different modes: a free viewing mode and a restricted viewing mode. In free viewing mode, the screen's light is emitted over a wider angular range than in restricted viewing mode. The screen is an LCD screen comprising two flat backlights with different emission angles. The user can switch on either backlight to activate the desired operating mode.

[0007] The present invention is based on the objective of providing an improved display system for a vehicle. The display system should be suitable for providing a display for the passenger of the vehicle without distracting or disturbing the driver. However, the display for the passenger should also be visible to the driver when desired.

[0008] The object of the present invention is solved according to the invention by a display system according to claim 1. Preferred embodiments are set forth in the dependent claims.

[0009] The display system according to the invention for a vehicle comprises a windshield and (at least) one screen. The windshield has a transparent viewing area and an opaque masking area. The screen is directed onto a display area which is arranged in the masking area of ​​the windshield. The windshield is equipped in the display area with a reflective layer which is suitable for reflecting the radiation from the screen (at least partially), thereby generating a display image.

[0010] According to the invention, the screen is suitable for operation in a first operating mode and in a second operating mode. In the first operating mode, the screen emits light within a first angular range; in the second operating mode, the screen emits light within a second angular range. The first angular range is smaller than the second angular range.

[0011] The user can switch between the first and second operating modes of the screen. In the first mode, a restricted viewing angle is achieved due to the smaller viewing angle, while in the second mode, a free or unrestricted viewing angle is achieved due to the larger viewing angle. If the display system is assigned to the passenger, the first mode can be selected if the display should not distract the driver and should therefore only be perceptible to the passenger. If, on the other hand, the driver also wants to see the display, the second mode can be selected. These are significant advantages of the present invention.

[0012] The windshield is designed for a vehicle and can therefore also be referred to as a vehicle windshield. In a preferred embodiment, it is the windshield of a motor vehicle, in particular a passenger car or truck.

[0013] The windshield is typically designed as a laminated glass pane, comprising an outer pane and an inner pane bonded together by a thermoplastic interlayer. The windshield is intended to separate the interior (vehicle interior) from the external environment in the forward-facing window opening of a vehicle (relative to the direction of travel). For the purposes of this invention, the term "inner pane" refers to the pane of the windshield facing the interior. The term "outer pane" refers to the pane facing the external environment.

[0014] The windshield has a top edge and a bottom edge, as well as two side edges running between them. The top edge is the edge that is intended to point upwards when installed. The bottom edge is the edge that is intended to point downwards when installed. The top edge is often also referred to as the roof edge and the bottom edge as the engine edge.

[0015] The outer pane and the inner pane each have an outer and an inner surface, and a circumferential side edge surface extending between them. For the purposes of the invention, the outer surface is defined as the main surface intended to face the external environment when installed. The inner surface is defined as the main surface intended to face the interior when installed. The inner surface of the outer pane and the outer surface of the inner pane face each other and are connected by the thermoplastic intermediate layer.

[0016] The outer and inner panes are preferably made of glass, particularly preferably of soda-lime glass, as is common for window panes. However, one or both panes can also be made of other types of glass, for example, quartz glass, borosilicate glass, or aluminosilicate glass, or of rigid, clear plastics, for example, polycarbonate or polymethyl methacrylate. The panes can be clear, tinted, or colored. The thicknesses of the outer and inner panes are preferably from 0.5 mm to 5 mm, and particularly preferably from 1 mm to 3 mm, and are independent of each other.

[0017] The thermoplastic interlayer (with the exception of any embedded functional films, which are often PET-based) is preferably based on polyvinyl butyral (PVB), ethylene-vinyl acetate (EVA), or polyurethane (PU), or on mixtures, copolymers, or derivatives thereof, particularly preferably on PVB. The interlayer typically consists of at least one thermoplastic film (bonding film), especially one based on PVB, EVA, or PU. This means that the film consists largely of the aforementioned polymer (proportion greater than 50% by weight). The film may contain other additives besides the polymer, particularly plasticizers.If the reflective layer is designed as a reflective film and embedded in the intermediate layer, the intermediate layer preferably comprises, in addition to this reflective film, at least two bonding layers (inner and outer bonding layer, wherein the inner bonding layer faces the inner disk and the outer bonding layer faces the outer disk), each of the bonding layers typically being formed from at least one bonding film, in particular based on PVB, EVA, or PU. The reflective film is arranged between the bonding layers. The thickness of the bonding film (or of each bonding film, if several are present) is preferably from 0.2 mm to 1 mm. For example, PVB films with standard thicknesses of 0.38 mm or 0.76 mm can be used.Instead of films, polymer coatings can also be used, especially if the thermoplastic layer in question is to be very thin, for example with a thickness of 0.005 mm to 0.1 mm or of 0.02 mm to 0.07 mm.

[0018] The windshield has an opaque masking area and a transparent viewing area. For the purposes of this invention, the term "masking area" refers to an area of ​​the windshield through which visibility is not possible. The light transmission of the masking area is less than 10%, preferably less than 5%, particularly preferably less than 2%, and most preferably essentially 0%. For the purposes of this invention, the term "viewing area" refers to an area of ​​the windshield that allows visibility through the windshield and is intended for viewing. The viewing area is therefore transparent. The light transmission of the viewing area is preferably at least 70%. "Light transmission" here refers to the total transmission, determined by the method for testing the light transmittance of motor vehicle windows specified in ECE-R 43, Annex 3, Section 9.1.

[0019] In a typical embodiment, the masking area surrounds the viewing area like a frame. The masking area is thus arranged all the way around the viewing area. Typically, the masking area forms the perimeter of the windshield and borders the side edge of the windshield. Therefore, in a preferred embodiment, the masking area is arranged in a perimeter of the windshield and surrounds the viewing area.

[0020] In a preferred embodiment, the display area is arranged in a section of the masking area adjacent to the lower edge of the windshield. The display area is thus positioned between the viewing area and the lower edge of the windshield. In the case of a frame-like masking area in the circumferential border region of the windshield, a section of the masking area borders each edge (upper edge, lower edge, first and second side edges), and the display area is preferably located in the section adjacent to the lower edge.

[0021] The masking area is preferably formed by an opaque, in particular black, print (masking print) on at least one of the surfaces of the outer pane and / or the inner pane, particularly preferably on the inner surface of the outer pane. The masking print typically consists of an enamel applied by screen printing and subsequently fired, which contains glass frits and colorants (in particular pigments). Such masking prints are commonly used, especially for vehicle windows. The pigment is typically a black pigment, for example carbon black, aniline black, bone black, iron oxide black, spinel black, and / or graphite. The masking print preferably has a thickness of 5 µm to 50 µm, particularly preferably 8 µm to 25 µm.

[0022] The masking area can alternatively be formed by an opaque polymeric film, which is part of the intermediate layer and is arranged between the reflective layer and the outer pane. For the purposes of the invention, an opaque film is understood to be a film with a light transmission in the visible spectral range of less than 5%, in particular 0%.

[0023] The masking area can also be formed completely or partially by a functional element with electrically controllable properties, which can be darkened. Such a functional element comprises an active layer or sequence of layers between two surface electrodes, by means of which an electrical voltage can be applied to the active layer(s) to adjust its optical properties. Functional elements that can be darkened in this way to form an opaque masking area are, in particular, electrochromic functional elements and SPD functional elements ( suspended particle device ) .The opaque masking area is only present when the functional element is in its darkened state. The functional element can be applied to one of the surfaces of the outer or inner pane, in particular the interior surface of the outer pane or the exterior surface of the inner pane. Alternatively, the functional element can be provided as a multilayer film and positioned between two layers of the interlayer.

[0024] In a further development of the invention, a permanent masking area is provided, which is formed in particular by a cover print (alternatively by an opaque polymeric film), and an area extending from this into the viewing area, which is provided with a functional element with electrically controllable properties (in particular an electrochromic functional element). The display area is arranged partly in the permanent masking area and partly in the area with said functional element. Depending on the switching state, the area with the functional element belongs to the viewing area (when the functional element is switched to transparent) or to the masking area (when the functional element is darkened or switched to opaque). If a display is to be generated that is located completely or partially in the area with the functional element, the functional element is darkened.If, on the other hand, only a display is to be created that is located in the permanent masking area, the functional element can be switched to transparent in order to increase the size of the see-through area.

[0025] The opaque element that forms the masking area (in particular the cover print, the opaque polymer film, and / or the functional element with electrically controllable properties) is positioned behind the reflective layer in the viewing direction so that the latter can be illuminated by the screen. The reflective layer is therefore closer to the screen than the opaque element.

[0026] The screen is directed at the display area and illuminates it to generate a display image. The area of ​​the windshield illuminated (or irradiable) by the screen is therefore the display area within the meaning of the invention. According to the invention, a reflective layer is arranged in the display area of ​​the windshield, which reflects the screen's radiation towards the user to generate the display image. The screen illuminates the display area with electromagnetic radiation in the visible spectral range to generate the display image, which the user perceives in the masking area. The radiation is particularly in the spectral range of 450 nm to 650 nm, for example with wavelengths of 473 nm, 550 nm, and 630 nm (RGB).

[0027] The reflective layer preferably has a reflectance of at least 10% relative to the screen's radiation, and particularly preferably at least 15%. This is advantageous for high intensity and good quality of the secondary display image. The reflectance is, for example, from 10% to 100% or from 15% to 30%. The reflectance describes the proportion of the total incident radiation that is reflected. It is expressed as a percentage (relative to 100% incident radiation) or as a dimensionless number from 0 to 1 (normalized to the incident radiation). Plotted as a function of wavelength, it forms the reflection spectrum. Within the scope of the present invention, the descriptions of the reflectance refer to the reflectance measured at an angle of incidence of 65° to the interior surface normal, which corresponds approximately to the irradiance of conventional screens.The information on reflectance refers to a reflectance measurement with a light source that emits uniformly in the considered spectral range with a normalized radiation intensity of 100%.

[0028] The reflective layer covers at least the display area. However, it can also extend beyond the display area, thus covering adjacent areas of the windshield. This can be advantageous, as it reduces the need for precise positioning of the reflective layer or helps avoid display errors at the edges of the image that might occur due to imperfect positioning of the reflective layer.

[0029] The reflective layer can be configured in various ways. In a first preferred embodiment, the reflective layer is configured as a metal-containing coating. The metal-containing coating can be applied to a surface of the outer or inner pane, for example, the interior surface of the outer pane, the exterior surface of the inner pane, or the interior surface of the inner pane. Alternatively, the coating can be provided on a carrier film, which is arranged between two layers of the thermoplastic intermediate layer. The carrier film, together with the coating, forms a reflective film. The carrier film is, for example, a film based on polyethylene terephthalate (PET), preferably consisting mainly of PET, with a thickness of 20 µm to 200 µm, preferably 25 µm to 75 µm.

[0030] The metal-containing coating can be a mirror-like metal layer that reflects essentially all of the screen's radiation (reflectivity of essentially 100% relative to the screen's radiation). Suitable metals include, for example, silver or aluminum. Suitable layer thicknesses range, for example, from 200 nm to 5 µm, and particularly from 800 nm to 1.5 µm. Alternatively, the metal-containing coating can be formed from a plurality of thin films, including at least one thin film based on a metal, preferably silver. Due to their IR-reflective and electrically conductive properties, coatings of this type are also known as solar control coatings ( solar control coating) or heated coatings are commonly used. The at least one metal-based layer preferably contains at least 99 wt.% silver and has a thickness of, for example, 5 nm to 20 nm. Such a coating exhibits (partially) reflective properties in the visible range, so that it can serve as a reflective surface for the display system. The coating preferably also contains dielectric thin films. The desired reflection characteristics, in particular the reflectance relative to the radiation from the screen, are achieved especially by the choice of materials and thicknesses of the individual layers. The conductive coating can thus be suitably adjusted, which is common practice in the technical field and well known to those skilled in the art. Dielectric layers or sequences of layers are typically arranged above and below the metal layer.If the coating comprises several metal layers, each metal layer is preferably arranged between two typically dielectric layers or layer sequences, such that a dielectric layer or layer sequence is arranged between adjacent metal layers. The coating is therefore a thin-film stack. n Metal layers and ( n + 1 ) dielectric layers or sequences of layers, wherein na natural number, where a lower dielectric layer or sequence of layers is alternately followed by a metal layer and a dielectric layer or sequence of layers. Common dielectric layers of such a thin-film stack are based, for example, on silicon nitride, silicon-metal mixed nitrides such as silicon zirconium nitride, titanium oxide, aluminum nitride, tin oxide, zinc oxide, or tin-zinc mixed oxide, and have a layer thickness of, for example, 3 nm to 200 nm. Also common are blocker layers, which protect the metal layers from degradation and are typically formed as very thin metal-containing layers based on niobium, titanium, nickel, chromium, and / or alloys thereof, with layer thicknesses of, for example, 0.1 nm to 2 nm.

[0031] In a second preferred embodiment, the reflective layer is designed as a purely dielectric coating. The dielectric coating can, in turn, be applied to a surface of the outer or inner pane, for example, the inner surface of the outer pane, the outer surface of the inner pane, or the inner surface of the inner pane. Alternatively, the coating can be provided on a carrier film (reflective film) and embedded between two layers of the intermediate layer, as described above in connection with the metal-containing coating. The dielectric coating is preferably a layer (for example, a thin film) made of a material with a higher refractive index (measured at 550 nm) than the substrate on which it is applied (outer pane, inner pane, or carrier film).The layer is based, for example, on aluminum nitride, silicon nitride, zirconium nitride, silicon-zirconium mixed nitride, zirconium oxide, tin oxide, zinc oxide, or tin-zinc mixed oxide, with titanium oxide being particularly preferred. The layer thickness is, for example, from 100 nm to 5 µm or from 500 nm to 2 µm. More complex multilayer coatings can also be used, in which layers with a higher refractive index (for example, based on titanium oxide or silicon nitride) and layers with a lower refractive index (for example, based on silicon oxide) are arranged alternately. The reflective effect is achieved through interference effects and can be precisely controlled by selecting the layer thicknesses.

[0032] In a third preferred embodiment, the reflective layer is designed as a purely dielectric polymeric film containing alternating layers with different refractive indices. The dielectric reflective film is preferably arranged between two layers of the intermediate layer and thus embedded within it. The film contains no metal coatings. It is a purely dielectric sequence of polymeric layers with a higher refractive index and polymeric layers with a lower refractive index, arranged alternately. At least one of the two layer types is preferably based on PET. The other layer type can also be based on PET, with the different refractive indices being achieved by suitable additives, based on a PET copolymer, or based on another polymer, for example, PMMA.By alternating layers with different refractive indices, optical interference effects are achieved which can be suitably adjusted for the respective application (in particular by selecting the layer thicknesses and refractive indices) in order to realize reflective properties in a desired spectral range. In this way, reflective properties in the visible spectral range can be achieved in order to use the film as a reflective surface for the display system according to the invention.

[0033] The screen illuminates the windshield with electromagnetic radiation in the visible spectrum via the inner pane to generate the displayed image, which can be perceived by a user inside the vehicle. The screen is therefore positioned on the inner side of the windshield and illuminates the windshield via the inner surface of the inner pane. The screen's radiation is (partially) reflected by the reflective coating.

[0034] The screen can be operated in two modes: a first mode with a restricted viewing angle, in which the screen emits light within a limited range, and a second mode with a free or unrestricted viewing angle, in which the screen emits light within a wider range. The first viewing angle is smaller than the second, thus achieving the restricted viewing angle of the first mode.

[0035] The user can switch between the first and second operating modes. This can be done manually or via voice control. In advanced training, it is also conceivable that the selection of the operating mode is automated by a driver assistance system, for example, switching from the second to the first operating mode when the driver assistance system detects a critical situation.

[0036] The display of the display system according to the invention is specifically intended for and assigned to a vehicle occupant (typically the front passenger). The first angular range is preferably selected such that this vehicle occupant can see the display, while another vehicle occupant positioned laterally offset to him (typically the driver) cannot see the display. The second angular range is preferably selected such that both the aforementioned vehicle occupant and the laterally offset other vehicle occupant can see the display.

[0037] The angular range over which the light is emitted determines the viewing angle of the display—that is, it defines the extent to which a viewer can look at the display area from an angle to the side and still be able to see it. The radiation emanating from a point on the screen is emitted in the form of a cone of light, with the angular range specifying the extent of this cone. It can be expressed quantitatively as the angle between the surface of the cone and the surface normal of the screen (determined at the point from which the cone originates). Within the scope of the present invention, the angular range is specified in this way: it is described as the angle between the peripheral rays of the cone, which define its boundaries, and the surface normal.A screen that emitted light only perpendicularly, exclusively along the surface normal and not in the form of a beam cone, would have an angular range of 0°. The more extended the beam cone, the greater the magnitude of the angular range.

[0038] It is possible that the light is not emitted in a rotationally symmetrical beam cone, but rather that the angular ranges differ in the horizontal and vertical directions. The terms "horizontal" and "vertical" refer to the display on the windshield: the vertical angular range defines the extent of the illuminated area in the vertical dimension of the windshield (direction between the top and bottom edges of the windshield), and the horizontal angular range defines the extent of the illuminated area in the horizontal dimension of the windshield (direction between the side edges). It is readily apparent from the intended application that, in this case, the angular range as defined by the invention refers to the horizontal angular range.The angular range is described as the angle between the rays of the screen at the edges of a horizontal section, which are emitted towards the side edges of the windshield, and the surface normal. The horizontal section is a section through that component of the emitted light which illuminates the windshield along a horizontal line between its side edges.

[0039] The horizontal viewing angle can also be referred to as the lateral viewing angle. The screen's lateral viewing angle determines the display's lateral viewing angle. "Lateral" refers to the intended viewing situation, where the viewer is positioned on the inside side of the windshield and looks at the inner surface of the windshield. The lateral viewing angle determines the extent to which a viewer positioned laterally relative to the display area can see the screen. The viewing angle thus defines the lateral viewing angle of the display.

[0040] The viewing angle can be determined by having a viewer look at the screen and move away from it laterally. From the position at which the display is no longer visible, the viewing angle can be calculated as the angle of the line connecting that position and the edge of the screen facing it to the normal of the screen's surface. To compare the viewing angles of different displays, they can be recorded, for example, with the same camera moving laterally away from the screen while keeping the camera pointed at it. The limit of the viewing angle is reached when the display is no longer perceptible in the camera recording.

[0041] The first angle range is typically from 15° to 90°, for example, from 15° to 60°, 20° to 50°, or 20° to 40°. The second angle range is typically from 30° to 90°, for example, from 40° to 90°, 50° to 90°, or 60° to 80°.

[0042] The screen is specifically designed as a backlit transmissive imager. The two operating modes are achieved primarily through the use of two different backlights that emit light at different angles. The screen can Alternatively, it can be operated with the first or the second backlight, thus realizing the two operating modes, or either only with the first backlight or with a combination of both backlights, thus realizing the two operating modes.

[0043] In a preferred embodiment, the screen comprises a first planar backlight, a second planar backlight, and a transmissive image source, arranged planarly one above the other in the specified order. The transmissive image source faces the windshield, and the first planar backlight faces away from it. The backlights are preferably at least as large as the transmissive image source so that the latter can be illuminated uniformly. One of the two backlights emits light in the first angular range, and the other emits light in the second angular range. Since the light from the first backlight must pass through the second backlight to illuminate the transmissive image source, the second backlight is transparent.This means that the second backlight has a transmittance of at least 70% compared to the radiation from the first backlight. Likewise, the second backlight should not scatter the light from the first backlight too much – the haze value of the second backlight is therefore preferably less than 7%, particularly preferably less than 2%, as measured according to ASTM D1003.

[0044] The screen is preferably operated in such a way that the two backlights are used alternately. This means that in the first operating mode (restricted viewing mode), only the first backlight is active, while the second backlight is switched off, and that in the second operating mode (unrestricted viewing mode), only the second backlight is active, while the first backlight is switched off. Alternatively, it is also conceivable that the first backlight with the smaller or restricted viewing angle is continuously active. In the first operating mode, it is then the only light source, while in the second operating mode, the second backlight with the larger or unrestricted viewing angle is additionally switched on.This also achieves a clear viewing mode in the second operating mode, whereby the radiation intensity in the first angular range is stronger due to the additional light source, and the display therefore appears brighter or more intense in the first angular range than in the remaining section of the second angular range (i.e., the section not overlapping with the first angular range). At least the second backlight can thus be switched on and off. Preferably, both backlights can be switched on and off separately, with switching one backlight on simultaneously switching the other backlight off.

[0045] In an advantageous embodiment, the first planar backlight emits light in the first angular range, and the second planar backlight emits light in the second angular range. The second operating mode is thus achieved by using the second backlight, which is arranged between the first backlight and the image sensor. The second backlight is preferably designed as a planar light guide equipped with a light source suitable for coupling light into the light guide via a side edge, and with extraction means suitable for coupling the light out of the light guide via a surface facing the image sensor.

[0046] A planar optical fiber is a layered or plate-like object designed to conduct light. It can also be called a light guide plate and has two main surfaces and a circumferential edge surface extending between them, which can also be called a side edge or simply a side edge. One of the main surfaces faces the image source, and the other faces the primary backlight. Suitable materials for the optical fiber include glass or transparent plastics such as polymethyl methacrylate (PMMA), polyethylene terephthalate (PET), or polycarbonate (PC). The light source is positioned such that the light emitted by the light source is coupled into the optical fiber via the side edge (or at least a portion of the side edge). There, the light propagates along the main surface of the optical fiber due to total internal reflection, which is the basis of its light-conducting effect.The light source is, for example, a single or multiple LEDs positioned along the side edge of the light guide. The light guide is equipped with coupling elements that cause the light to be coupled out of the light guide via the surface facing the image sensor and then illuminate the image sensor. This does not mean that all the light must be coupled out exclusively via this main surface – typically, a certain proportion of the light is coupled out via the opposite main surface, the one facing the first backlight. This is unproblematic, although this portion of the light then does not contribute to the backlighting of the image sensor and is essentially lost. It is therefore advantageous if as much of the light as possible is coupled out via the main surface facing the image sensor.The output coupling means can be designed, for example, as light-scattering structures that are formed on one of the main surfaces of the optical fiber and / or embedded within the optical fiber. An example of this is a local or full-surface roughening or structuring of at least one of the main surfaces, which prevents total internal reflection and therefore leads to output coupling. The roughening or structuring is preferably present on the main surface of the optical fiber that faces the image sensor in order to optimize the emission in this direction. Instead of roughening, microlenses, microprisms, or diffractive structures (such as holograms or diffraction gratings) can, for example, be applied to or formed on the main surface.These elements can be attached to the main surface as prefabricated components, for example by gluing; formed from a UV-curing or thermally curing lacquer that is applied to the main surface, structured or shaped with a tool, and then cured; or formed from the main surface of the optical fiber itself by machining with a tool. Nanoparticles, for example, can be embedded in the optical fiber as extraction agents, particularly if the optical fiber is made of a polymeric material, preferably with particle sizes of 150 nm to 500 nm.

[0047] The first backlight preferably comprises a planar base element (lighting element, planar light source) that emits the light, and a microlamellar film that restricts the beam angle to the first angular range. The microlamellar film ( micro louvreThe microlouver film is arranged between the base element and the second backlight, preferably on the main surface of the base element facing the second backlight. The microlouver film is a polymeric film in which parallel louvers with widths and spacings in the micrometer range are formed, limiting the angular range of the transmitted light. The angular range can be adjusted by the depth of the louvers and the spacing of adjacent louvers. Such microlouver films are known per se and are used, for example, as privacy filters on notebook monitors. To limit the lateral angular range of the display, the microlouver film is arranged such that the projection of the louvers onto the windshield runs essentially vertically between the upper and lower edges of the windshield.

[0048] The basic element, like the second backlight, can be designed as a planar light guide equipped with a light source capable of coupling light into the light guide via a side edge, and with coupling elements capable of coupling the light out of the light guide via a surface facing the image sensor. In the first backlight, the light sources can also be arranged on the main surface of the light guide facing away from the image sensor, instead of on the side edge. Alternatively, electroluminescent films, cold cathode tubes, LED panels (two-dimensional LED arrays), planar OLED emitters, or other area emitters can be used as the basic element.

[0049] The first backlight may include further elements that are well known to those skilled in the art, such as a diffuser, one or more light collimators, or optical filters. For example, the first backlight may be composed of the following elements, in the order given: base element - diffuser - light collimator(s) - microlouver filter.

[0050] The transmissive image sensor converts the light from the backlights into the desired display, which is then projected onto the windshield. The image sensor thus imbues the light from the backlights with information as it passes through it. The transmissive image sensor is preferably a liquid crystal display element (LCD panel).

[0051] In a particularly advantageous embodiment, the radiation from the screen striking the windshield is p-polarized. Specifically, the radiation is essentially purely p-polarized – the p-polarized component is therefore 100% or deviates only insignificantly from this. The polarization direction is specified with respect to the plane of incidence of the radiation on the windshield. P-polarized radiation is defined as radiation whose electric field oscillates in the plane of incidence. S-polarized radiation is defined as radiation whose electric field oscillates perpendicular to the plane of incidence. The plane of incidence is defined by the incidence vector and the surface normal of the windshield. The polarization, and in particular the proportion of p- and s-polarized radiation, is determined at a point within the display area, preferably at the geometric center of the display area.If the windshield is curved, which is usually the case, this affects the plane of incidence of the radiation. Therefore, slightly different polarization components can occur in other areas, which is unavoidable for physical reasons. To provide p-polarized radiation, a polarization filter or a polarizing beam splitter can be placed in the beam path between the screen and the windshield.

[0052] The screen's radiation preferably strikes the windshield at an angle of incidence of 45° to 70°, particularly 60° to 70°. In an advantageous embodiment, the angle of incidence deviates from Brewster's angle by a maximum of 10°. The p-polarized radiation is then only minimally reflected from the windshield surfaces. As a result, the reflective coating represents the only significant reflective surface for the radiation. If the radiation were also significantly reflected from the interior surface of the inner pane (air-glass interface), a so-called ghost image would occur, which would be at least disturbing, if not completely unacceptable, for the user. The angle of incidence is the angle between the radiation's incidence vector and the interior surface normal (i.e., the surface normal to the interior external surface of the windshield) at the geometric center of the display area.The Brewster angle for an air-glass interface in the case of soda-lime glass, which is commonly used for window panes, is 57.2°. Ideally, the angle of incidence should be as close as possible to this Brewster angle. However, angles of incidence of 65°, for example, can also be used. These are common for HUD projection setups, are easily implemented in vehicles, and deviate only slightly from the Brewster angle, so that the reflection of the p-polarized radiation increases only marginally.

[0053] The windshield has at least one display area with the screen according to the invention, featuring two operating modes. The windshield can also have one or more further display areas, namely one or more display areas according to the invention (each illuminated by a screen according to the invention with the two operating modes) and / or one or more conventional display areas (each illuminated by a conventional screen with only one operating mode). In an advantageous embodiment, all display areas according to the invention are located for the passenger.

[0054] The windshield is preferably curved in one or more directions, as is common for automotive windshields. Typical radii of curvature range from approximately 10 cm to approximately 40 m. The inner surface of the inner pane is usually concave, while the outer surface of the outer pane is convex. However, a windshield can also be flat.

[0055] Windscreens can be manufactured using methods known per se. A stack of layers is created by arranging the individual components (outer pane, interlayer film(s), inner pane) on top of each other in the required sequence. This stack of layers is then laminated to form a composite windscreen. This is done in particular using methods known per se, such as autoclave processes, vacuum bag processes, vacuum ring processes, calender processes, vacuum laminators, or combinations thereof. The bonding of the outer and inner panes via the interlayer is typically achieved under the influence of heat, vacuum, and / or pressure.

[0056] If the reflective layer is a coating on the outer or inner pane, this coating is preferably applied to the respective pane surface by physical vapor deposition (PVD), particularly preferably by cathode sputtering, and most preferably by magnetron sputtering. In principle, however, the coating can also be applied, for example, by chemical vapor deposition (CVD), such as plasma-enhanced chemical vapor deposition (PECVD), by evaporation, or by atomic layer deposition (ALD). atomic layer deposition , ALD). The reflective layer is preferably applied to the surface of the discs before they are bonded together to form a composite disc (lamination).

[0057] If, on the other hand, the reflective layer is provided as a reflective film (a metal-containing or purely dielectric coating on a carrier film or a purely dielectric polymeric film), it is arranged between two thermoplastic bonding layers and together they form the intermediate layer. The bonding layers are preferably each provided in the form of at least one thermoplastic bonding film (especially a PVB film). The reflective films can generally be purchased, for example as a PET carrier film with an electrically conductive coating or as a purely dielectric reflective film with different individual layers that alternately have a higher and a lower refractive index.They can be produced by depositing an electrically conductive coating or a purely dielectric coating onto a PET carrier film, in particular using the thin-film coating processes mentioned above, or by co-extrusion or multi-extrusion of two materials with different refractive indices to form a purely dielectric reflective film.

[0058] The masking area can be formed by applying an opaque enamel ink to a surface of the panes, particularly the inner surface of the outer pane, especially by means of a screen printing process. The enamel ink is then fired into the pane surface, forming an opaque masking layer that constitutes the masking area. Alternatively, the masking area can be formed by an opaque polymeric film. In this case, one of the bonding layers is not formed by a single homogeneous bonding film, but rather by a combination of a section of an opaque bonding film and a section of a transparent bonding film. The bonding layer with the opaque bonding film is positioned between the reflective layer and the outer pane.If the masking area (or at least part of it) is formed by a functional element with electrically switchable optical properties, the necessary layer system is either applied to one of the surfaces of the outer or inner pane before lamination, or the functional element is provided as a prefabricated multilayer film and inserted between two bonding layers before lamination.

[0059] If the windshield is to be curved, the outer and inner panes are preferably bent before lamination and preferably after any coating processes to bring them into a cylindrical or spherical shape. Preferably, the outer and inner panes are bent congruently together (i.e., simultaneously and using the same tool) because this ensures that the shape of the panes is optimally matched for the subsequent lamination. Typical temperatures for glass bending processes are, for example, 500°C to 700°C. At these temperatures, the glass panes become plastically deformable and can be bent into the desired shape using known bending methods, such as gravity bending, press bending, suction bending, or combinations thereof.

[0060] The invention further comprises a vehicle which has a driver's seat and a passenger seat and which is equipped with a display system according to the invention. The windshield of the vehicle is used as a projection surface of the display system and is illuminated by at least one screen which can be operated in the first operating mode and in the second operating mode.

[0061] The driver's and passenger's seats are arranged side-by-side behind the windshield. The windshield can be imaginarily divided in half by a central dividing line running between its top and bottom edges. One half is then assigned to the driver's seat and positioned in front of it (in the direction of travel), while the other half is assigned to the passenger's seat and positioned in front of it (in the direction of travel). When the driver and passenger are facing straight ahead, each looks through their assigned half of the windshield.

[0062] In an advantageous embodiment, the display area according to the invention is assigned to the passenger and arranged in front of the passenger seat. This means that the screen according to the invention, with its two operating modes, is designed to generate a display for the passenger. The corresponding display area is therefore arranged in the half of the windshield that corresponds to the passenger seat and is located on the passenger side. The advantages of the display system according to the invention are particularly evident here because the passenger can switch to the first operating mode with the limited viewing angle if the driver is not to be disturbed by the display.

[0063] Multiple display areas can also be assigned to the passenger and arranged in front of the passenger seat, each illuminated by its own screen. In this case, preferably all screens of the display areas assigned to the passenger are designed according to the invention and are thus suitable for operation in the two different operating modes.

[0064] In one embodiment of the invention, (at least) one further display area is provided, which is assigned to the driver and arranged in front of the driver's seat. A further screen is directed onto this additional display area to generate a display image by reflection off a reflective layer. Multiple display areas can also be assigned to the driver and arranged in front of the driver's seat, each illuminated by its own screen.

[0065] The display area assigned to the driver can also be illuminated by a screen according to the invention with both operating modes. However, since the passenger being disturbed by the driver's display is less critical, a conventional screen is preferably used, which is only suitable for operation in a single operating mode (i.e., with a single viewing angle). Since conventional screens are typically less complex and therefore less expensive, this is advantageous with regard to production costs. In the aforementioned operating mode, the screen preferably emits light in the second viewing angle (unobstructed view mode), so that the passenger can also see the driver's display. Alternatively, the screen can also emit light in the first viewing angle (restricted view mode).

[0066] Multiple display areas can also be assigned to the driver and positioned in front of the driver's seat, each illuminated by its own screen. In this case, preferably all screens of the display areas assigned to the passenger are of a conventional design and therefore only suitable for operation in a single operating mode (preferably the operating mode with the second viewing angle and unobstructed view).

[0067] In a training course, a screen like the one described in WO2019034557A1 can also be used. This screen has a first area where it operates in two different modes with different angular ranges, and a second area where it operates in only one mode with a single angular range. Such a screen can be implemented, for example, with a first and second backlight, as described above, where the microlouver film for limiting the angular range is only present in the first area of ​​the screen. In the second area, the first backlight then also emits light with the second angular range.Such a screen can, for example, be positioned in the area of ​​the vehicle's center console and illuminate a display area that is partially located in the half of the windshield assigned to the driver's seat and partially in the half assigned to the passenger's seat. The first area of ​​the screen, with its two operating modes, then preferably illuminates the portion of the display area in the half of the windshield assigned to the passenger's seat, and the second area of ​​the screen, with its single operating mode, illuminates the portion of the display area in the half of the windshield assigned to the driver's seat.

[0068] The display area(s) assigned to the passenger primarily show entertainment content, such as a television program, videos, computer games, or internet data. The display area(s) assigned to the driver primarily show status information that was previously typically displayed on the dashboard, such as the time, vehicle speed, engine speed, coolant temperature, interior or exterior temperature, information from the entertainment system (such as the currently playing radio station), or navigation system data. The image from one or more rear-facing cameras can also be displayed for the driver to supplement or replace the conventional exterior or rearview mirrors.Displaying this information in the masked area of ​​the windshield has the advantage that the driver does not have to turn their gaze as far from their actual field of vision as with conventional displays, which is beneficial for both safety and ergonomic reasons. In semi-autonomous driving, the driver can regain control of the vehicle more quickly. A more flexible human-machine interface is provided, allowing the user, for example, to determine the position of individual displays. The semi-virtual display image allows for faster refocusing of the eyes on the road. Furthermore, the presentation is aesthetically pleasing.

[0069] The invention is explained in more detail below with reference to a drawing and exemplary embodiments. The drawing is a schematic representation and not to scale. The drawing does not limit the invention in any way.

[0070] They show: Fig. 1 a top view of a windshield of a display system according to the invention in a vehicle, Fig. 2 a cross-section through a display system according to the invention with the windshield made of Figure 1 , Fig. 3 a cross-section through the windshield made of Figure 1 Fig. 4 shows a cross-section through a further embodiment of the windshield of a display system according to the invention, Fig. 5 shows a cross-section of the screen of the display system. Figure 2 , Fig. 6 shows another cross-section of the screen of the display system Figure 2 ,

[0071] Figure 1, Figure 2 and Figure 3 Each figure shows a detail of a display system according to the invention in a vehicle. The display system consists of a windshield 10 and a screen 20. Figure 1 This shows a top view of the windshield 10, Figure 2 a cross-section through the display system along the in Figure 1 marked section line XX' and Figure 3 a cross-section through the windscreen 10 along the same section line with a larger number of details.

[0072] The windshield 10 is installed in a vehicle, in particular a passenger car. Figure 1 The illustration also shows a view of the windshield 10 from inside the vehicle. The vehicle is equipped with a driver's seat and a passenger seat. The driver's seat is located behind the left half of the windshield 10 shown in the illustration, and the passenger seat behind the right half. It is therefore a so-called left-hand drive vehicle for right-hand traffic, as is common in continental Europe and the USA, among other places. The left half of the windshield 10 is assigned to the driver and is located in front of the driver's seat, while the right half is assigned to the passenger and is located in front of the passenger seat.

[0073] The windshield 10 has an opaque masking area M, which is arranged in a circumferential edge region and surrounds a transparent viewing area D like a frame. The windshield 10 has an upper edge O pointing upwards (towards the vehicle roof) and a lower edge U pointing downwards (towards the engine compartment), with two side edges running between them. Such masking areas M are common in vehicle windows – they serve to protect the adhesive used to bond the windshield 10 to the vehicle body from UV radiation. Furthermore, any electrical connections or the side edge of an embedded functional film can be concealed in the masking area M.

[0074] The windshield 10 has, by way of example, two display areas A and B. Both display areas A and B are located in the section of the masking area M adjacent to the lower edge U. Display area A is assigned to the passenger F and is located in the half of the windshield 10 in front of him. It is intended to display information for the passenger F. This could be, in particular, entertainment content, such as films, internet data, or computer games. Display area B is assigned to the driver and is located in the half of the windshield 10 in front of him. It is intended to display information for the driver. This could be, in particular, vehicle status information (for example, the vehicle speed), navigation instructions, or the image from a rear-facing camera.

[0075] To generate the display, a screen 20 is directed at and illuminates display area A. Display area B is also illuminated by another screen, which is not shown. The aim of the invention is to implement the display in display area A in such a way that the driver is not disturbed by it. However, the driver should be able to see the display in display area A if desired. For this purpose, a projector 20 is used according to the invention, which can be operated in two different modes: a first mode in which the light from the screen 20 is emitted within a narrower angular range (restricted viewing mode), and a second mode in which the light from the screen 20 is emitted within a wider angular range (unrestricted viewing mode). The driver or passenger can select the operating mode in which the screen 20 is used.A conventional screen is used for display area B, operating in only one mode. This mode features a wider angular distribution of the emitted light, ensuring that the passenger can also see the display. The screens are located below their respective display areas A and B.

[0076] The windshield 10 consists of an outer pane 1 and an inner pane 2, which are bonded together via a thermoplastic interlayer 3. In its installed position, the outer pane 1 faces the external environment, and the inner pane 2 faces the vehicle interior. For the sake of simplicity, the windshield 10 is shown as flat, although vehicle windshields are usually curved, which is also preferred within the scope of the present invention. The outer pane 1 and the inner pane 2 are made of soda-lime glass. The outer pane 1 has, for example, a thickness of 2.1 mm, and the inner pane 2 a thickness of 1.6 mm.

[0077] The masking area M is formed by a black masking print 8, which is applied to the interior surface of the outer pane 1 facing the intermediate layer 3. Such a masking print 8 is common in the automotive sector: an enamel-like paint is screen-printed onto the pane surface. It contains a black pigment and glass frits, which are baked into the pane surface.

[0078] The intermediate layer 3 has a multi-layered structure. It comprises an outer bonding layer 5, which faces the outer pane 1, and an inner bonding layer 6, which faces the inner pane 2. Bonding layers 5 and 6 are transparent and made of commercially available PVB film, which also contains plasticizers. The outer bonding layer 5 has a thickness of 0.76 mm, and the inner bonding layer 6 has a thickness of 0.38 mm.

[0079] A reflective layer 4, designed as a reflective foil, is arranged between the connecting layers 5 and 6. The reflective layer 4 is thus connected to the outer disk 1 via the outer connecting layer 5 and to the inner disk 2 via the inner connecting layer 6. The reflective layer 4 is positioned in the section of the masking area M adjacent to the lower edge U such that it covers both display areas A and B.

[0080] The screen 20 is located on the interior side of the windshield 10. The inner pane 2 of the windshield 10 therefore faces the screen 20. The screen 20 illuminates the display area A to generate the displayed image. The radiation from the screen 20 that strikes the windshield 10 is essentially purely p-polarized. This is achieved, for example, by placing a polarization filter between the screen 20 and the windshield 10. Since the screen 20 illuminates the windshield 10 at an angle of incidence of approximately 65°, which is close to Brewster's angle, the radiation from the screen 20 is reflected only minimally from the interior surface of the windshield 10 facing away from the intermediate layer 3.The light from screen 20 is essentially reflected only at the reflective layer 4, so that a clear display image without disturbing ghost images is produced, which the viewer, in this case the passenger F, can perceive.

[0081] For example, the reflective layer 4 is a purely dielectric reflective film, which is composed of a sequence of polymeric dielectric layers, the individual layers having alternating higher and lower refractive indices. Due to interference, the reflective films exhibit reflective properties, particularly with respect to the radiation from the screen 20.

[0082] Figure 4Figure 1 shows a cross-section through another windshield 10, which can be used for a display system according to the invention. The outer pane 1 with the cover print 8, the inner pane 2, the outer connecting layer 6 and the inner connecting layer 6 are designed in the same way as in the example of Figure 1. Figure 3An electrochromic film 7 is arranged between the outer bonding layer 5 and the inner bonding layer 6, in an area extending from the marking area into the viewing area D. The electrochromic film 7 can be electrically darkened, thereby effectively enlarging the masking area M. The reflective layer 4 is applied to the inner surface of the inner disc 2, facing away from the intermediate layer 3, and again covers the entire display area, which in this case is located partly in the static masking area M formed by the masking print 8 and partly in the dynamic masking area formed by the electrochromic film 7. The reflective layer 4 is, for example, a sputtered dielectric coating made of a thin film of titanium oxide.The electrochromic film 7 allows the masking area M and the display area A to be enlarged depending on the situation, for example, when a large display is required and complete visibility through the actual viewing area D is not necessary.

[0083] The designs of the reflection layers 4 in the Figures 3 and 4 These are only examples. Alternatively, the reflective layer 4 can be replaced, for example, by a reflective foil as shown in Figure 3 The system can be realized as a PET carrier film with a metal-containing coating. Alternatively, a metal-containing coating can be applied as a reflective layer 4 to the outer surface of the inner pane 2 facing the intermediate layer 3. The reflective layer 4 can have partially reflective properties towards the light from the screen 20 or be designed like a mirror and reflect essentially all of the radiation.

[0084] Figure 5 shows a cross-section through screen 20 of the display system Figure 2 The screen 20 is composed of a first planar backlight 21, a second planar backlight 22 and a transmissive image transmitter 23. The elements are arranged planarly on top of each other in the specified order, with the image transmitter 23 facing the windshield 10.

[0085] The image generator 23 is an LCD panel which is illuminated either by the first backlight 21 or the second backlight 22. The first backlight 21 emits light in a first angular range β 1 and the second backlight 22 emits light in a second angular range β 2. The angular range β 1 is smaller than the second angular range β 2. By using the first backlight 21 with the smaller angular range β 1, the operating mode with the restricted viewing mode is implemented ( Figure 5a ), by using the second backlight 22 with the larger angular range β 2 the operating mode with the free or unrestricted viewing mode ( Figure 5b ).

[0086] The cross-sectional view shows a section through the component of the emitted light that illuminates the windshield 10 along a horizontal line between its side edges. This radiation component is therefore also referred to as the horizontal component. The angular ranges β1 and β2 are determined as the angles between the marginal rays that laterally limit the beam cone emanating from a point in the horizontal component, and the surface normal at said point. The angular ranges define the extent to which a viewer can deviate laterally from the intended viewing position (directly in front of the display area) and still recognize the display. During operation in restricted viewing mode ( Figure 5aWith the smaller angular range β 1, the display is no longer visible if the viewer is positioned slightly laterally to display area 4. This means that a driver positioned significantly laterally to display area 4 cannot see the display and is therefore not disturbed or distracted by it. When operating in free view mode ( Figure 5b With the larger angular range β 2, the display is still clearly visible even from a laterally offset position. In this case, the driver can perceive the display in display area 4.

[0087] Figure 6 shows another cross-section through screen 20. Figure 5with a greater number of details. The second backlight 21 is formed from a planar light guide 22a, for example made of glass or PMMA. The light guide 22a has two main surfaces, one facing the image sensor 23 and the other facing the first backlight 21, and a side edge (more precisely: side edge surface) extending between them. A light source 22b, for example a plurality of LEDs, is arranged on the side edge, the light from which is coupled into the light guide 22a via the side edge when the second backlight 22 is operated and propagates through it by total internal reflection at the main surfaces. The main surface of the light guide 22a facing the image sensor 23 is provided with extraction means 22c, for example microprisms or diffractive structures.The extraction means 22c are schematically arranged over the entire main surface, but are typically distributed only over uniformly distributed, locally limited areas. By means of the extraction means 22c, the light is (partially) extracted from the light guide 22a via the main surface facing the image sensor 23, thereby back-illuminating the image sensor 23.

[0088] The first backlight 21 is formed from a planar lighting element 21a (basic element, planar emitter). The lighting element 21a can, for example, be designed similarly to the first backlight, using a light guide through whose side edge light from a light source is coupled in, with the light being coupled out again via the main surface by coupling means. However, other configurations are also conceivable, such as electroluminescent films, OLEDs, or LED arrays. A microlamellar film 21b is applied to the main surface of the basic element 21a facing the second backlight 22, which creates the restricted angular range β 1 of the first backlight 21.

[0089] The screen may contain other components not shown, such as beam shaping components (like collimators and / or diffusers) or optical filters (especially interference coatings) or other coatings (for example, antireflection coatings). Reference symbol list:

[0090] (10) Windshield (1) Outer pane (2) Inner pane (3) Thermoplastic interlayer (4) Reflective layer (5) Outer bonding layer of interlayer 3 (6) Inner bonding layer of interlayer 3 (7) Electrochromic film (8) Cover print (20) Screen (21) First area backlight of the screen 20 (21a) Illumination element of the first area backlight 21 (21b) Microlamellar film of the first area backlight 21 (22) Second area backlight of the screen 20 (22a) Area light guide of the second area backlight 22 (22b) Light source of the second area backlight 22 (22c) Output coupling means of the second area backlight 22 (23) Transmissive image transmitter of the screen 20 (F)Viewer / Passenger (M)Windscreen masking area 10 (D)Windscreen viewing area 10 (A)Windscreen display area 10 (with two operating modes) (B)Further windscreen display area 10 (with one operating mode) (O)Top edge of windscreen 10 (U)Bottom edge of windscreen 10 (β 1 )first viewing angle of the screen 20 (β 2 )second viewing angle of the screen 20 X-X's intersection line

Claims

1. A display system for a vehicle, comprising - a windscreen (10) having a transparent see-through region (D) and an opaque masking region (M), and - a screen (20) which is directed at a display area (A) arranged in the masking region (M), wherein the windscreen (10) is equipped in the display area (A) with a reflection layer (4) which is suitable for reflecting the radiation of the screen (20) in order to generate a display image, characterised in that the screen (20) is suitable for operation in a first operating mode and in a second operating mode, wherein the screen emits light within a first angular range (β1) in the first operating mode and emits light within a second angular range (β2) in the second operating mode, wherein the first angular range (β1) is smaller than the second angular range (β2).

2. The display system according to claim 1, wherein the screen (20) comprises - a first planar backlight (21), - a second planar backlight (22), and - a transmissive imager (23), which are arranged surface-to-surface one above the other in the order given, wherein one of the two backlights (21, 22) emits light within the first angular range (β1) and the other of the two backlights (21, 22) emits light within the second angular range (β2).

3. The display system according to claim 2, wherein - the first planar backlight (21) emits light within the first angular range (β2), and - the second planar backlight (22) emits light within the second angular range (β2) and is designed as a planar light guide (22a) which is provided with a lighting means (22b) suitable for coupling light into the light guide (22a) via a lateral edge, and with coupling-out means (22c) suitable for coupling the light out of the light guide (22a) via a surface facing the imager (23).

4. The display system according to either claim 2 or claim 3, wherein the transmissive imager (23) is designed as a liquid crystal display element.

5. The display system according to any one of claims 2 to 4, wherein the first planar backlight (21) comprises a planar lighting element (21a) and a micro-louver film (21b) arranged between the lighting element (21a) and the second planar backlight (22).

6. The display system according to any one of claims 1 to 5, wherein the reflection layer (4) is designed as - a metal-containing coating or - a purely dielectric coating or - a purely dielectric polymeric film which contains alternating individual layers with different refractive indices.

7. The display system according to any one of claims 1 to 6, wherein the masking region (M) is formed - by a cover imprintment (8) - by an opaque polymeric film as part of the intermediate layer (3) and / or - by a functional element having electrically controllable properties, in particular an electrochromic functional element.

8. The display system according to any one of claims 1 to 7, wherein - the windshield (10) has an upper edge (O), a lower edge (U), and two lateral edges extending therebetween, and - the display area (B) is arranged in the portion of the masking region (M) adjoining the lower edge (U).

9. The display system according to any one of claims 1 to 8, wherein the radiation of the screen (20) impinging on the windshield (10) is p-polarised.

10. The display system according to any one of claims 1 to 9, wherein the windshield (10) is a composite pane composed of an outer pane (1) and an inner pane (2), which are connected to one another via a thermoplastic intermediate layer (3).

11. A vehicle having a driver's seat and a front passenger's seat and equipped with a display system according to any one of claims 1 to 10.

12. The vehicle according to claim 11, wherein the display area (A) is arranged in the half of the windshield (10) that is located on the front passenger seat side.

13. The vehicle according to claim 12, wherein the angular range (β1) is selected in such a way that the display of the display area (A) is not perceptible from the driver's seat.

14. The method according to either claim 12 or claim 13, wherein - a further display area (A) is arranged in the half of the windshield (10) that is located on the front passenger seat side, - another screen is directed at the further display area (B), and - the further screen is only suitable for operation in a single operating mode in which the screen preferably emits light within the second angular range (β2).