Composite pane having a transmitter and / or receiver of electromagnetic radiation and an electrically switchable mirror element

Abstract

The present invention relates to a composite pane (10) for a vehicle, comprising an outer pane (1) having an exterior-side surface (I) and an interior-side surface (II) and comprising an inner pane (2) having an exterior-side surface (III) and an interior-side surface (IV), wherein the interior-side surface (II) of the outer pane (1) and the exterior-side surface (III) of the inner pane (2) are joined to one another via a thermoplastic intermediate layer (3), wherein a transmitter and / or receiver of electromagnetic radiation is secured to the interior-side surface (I) of the inner pane (2) and its optical beam path runs through a sensor region (S) of the composite pane, wherein the composite pane is provided with an electrically switchable mirror element (7) in the sensor region (S).

Description

[0001] SAINT-GOBAIN SEKURIT FRANCE 2025082-WO-PCT

[0002] Composite disc with a transmitter and / or receiver of electromagnetic radiation and an electrically switchable mirror element

[0003] The invention relates to a composite disc equipped with a transmitter and / or receiver of electromagnetic radiation and an electrically switchable mirror element, a vehicle equipped with the composite disc and a method for controlling the mirror element of the vehicle.

[0004] Modern vehicles are increasingly equipped with sensors that simplify operation for the user, particularly as part of so-called Advanced Driver Assistance Systems (ADAS). Examples of such sensors include cameras, which automatically detect traffic signs, lanes, or oncoming traffic, and lidar (light detection and ranging) modules, which determine the spatial position and speed of objects in the environment. These sensors are typically mounted on the inner surface of the windshield, and their optical path passes through a sensor area within the windshield. In the future, such sensors could also become relevant for other vehicle windows, especially the rear window, with regard to autonomous driving.Vehicle windscreens with integrated cameras are disclosed, for example, in DE102004057322A1, DE102012204192A1, WO2022167333A1 and DE102012105434A1. Vehicle windscreens with integrated optical sensors, in particular lidar systems, are disclosed, for example, in WO2021053138A1, WO2022117943A1 and W02024069105A1.

[0005] To improve thermal comfort in the vehicle's interior and prevent excessive heating from sunlight, vehicle windows are often made with tinted glass or equipped with IR-reflective coatings. However, this is not possible in the sensor area because it would interfere with sensor operation. For sensors that operate with infrared radiation, such as lidar modules, an IR-reflective coating or tinted glass would reduce the signal intensity. For sensors that operate with radiation in the visible spectrum, such as cameras, tinted glass would reduce the signal intensity, and an IR-reflective coating could lead to optical distortions. Windshields with optical sensors are therefore typically made of untinted clear glass, and any IR-reflective coating is removed from the sensor area.SAINT-GOBAIN SEKURIT FRANCE 2025082-WO-PCT.

[0006] Consequently, there is no thermal shielding in the sensor area, meaning that sunlight can cause it to reach high temperatures. This is especially true in summer when the vehicle is parked, as neither airflow nor the vehicle's climate control system reduces the temperature. This poses a risk of overheating the sensor and its electronic components, which can sometimes lead to sensor failure.

[0007] WO2024223925 discloses a composite disc with an electrically switchable mirror element which can be electrically switched from a transparent to a mirrored state.

[0008] The present invention is based on the objective of providing an improved composite glass that can be used as a vehicle window and is equipped with a transmitter and / or receiver of electromagnetic radiation, wherein overheating of the transmitter and / or receiver is effectively prevented in strong sunlight when the vehicle is parked.

[0009] The object of the present invention is achieved according to the invention by a composite disk according to claim 1. Preferred embodiments are described in the dependent claims.

[0010] The composite glass pane according to the invention is intended for use in a vehicle, i.e., as a vehicle window (window pane of a vehicle). It is designed to separate the interior (vehicle interior) from the external environment in a window opening, in particular the window opening of a vehicle.

[0011] The laminated glass pane comprises an outer pane and an inner pane, which are bonded together via an intermediate layer (for example, thermoplastic). For the purposes of the invention, the inner pane refers to the pane of the laminated glass facing the vehicle interior. The outer pane refers to the pane facing the external environment. The outer pane and the inner pane each have an outer and an inner surface and an intermediate, circumferential side edge surface. For the purposes of the invention, the outer surface refers to the main surface which, in the installed position, is intended to face the external environment. For the purposes of the invention, the inner surface refers to the SAINT-GOBAIN SEKURIT FRANCE 2025082-WO-PCT

[0012] The invention designates the main surface which, in the installed position, is intended to face the interior. The interior surface of the outer pane and the exterior surface of the inner pane face each other and the intermediate layer and are connected to each other by the intermediate layer.

[0013] The composite pane according to the invention is equipped with at least one transmitter and / or receiver of electromagnetic radiation, which is attached to the inner surface of the inner pane. The optical beam path of the transmitter and / or receiver passes through a region of the composite pane, which, for the purposes of the invention, is referred to as the sensor region. The sensor region can also be referred to as the transmission region and is sometimes also known as a camera window or sensor window.

[0014] According to the invention, the laminated glass is equipped in the sensor area with an electrically switchable mirror element. The mirror element can be electrically switched between a transparent and a reflective state. This makes it possible to set the sensor area to be transparent when the vehicle is in operation, so that the transmitter and / or receiver can perform its function. When the vehicle is parked, the mirror element can be switched to the reflective state, so that at least the portions of solar radiation in the visible spectral range, through which a large part of the energy input occurs, are reflected. These portions are reflected back outwards and therefore cannot contribute to heating the sensor area and the transmitter and / or receiver located behind it, thus protecting the transmitter and / or receiver from overheating and extending its service life.The electrically switchable mirror element, in its reflective state, is thus suitable for reflecting light striking the mirror element via the outer pane (i.e., "from the outside"). Furthermore, in its reflective state, the mirror element clearly signals to passersby that they are not currently being filmed. These are significant advantages of the present invention.

[0015] The laminated glass according to the invention is preferably a vehicle window. The vehicle can be any means of transport for air, water, or land traffic. The laminated glass is particularly preferably a windshield, side window, or rear window of a motor vehicle, especially a passenger car. Transmitters and / or receivers of electromagnetic radiation are already commonly used in windshields. Their application is also described in SAINT-GOBAIN SEKURIT FRANCE 2025082-WO-PCT.

[0016] Rear windows or side windows will gain in importance in the future, especially in connection with autonomous driving.

[0017] The outer and inner panes are preferably made of glass, in particular soda-lime glass, which is common for window panes. However, the glass pane can also be made of other types of glass (for example, borosilicate glass, quartz glass, aluminosilicate glass). The outer and inner panes preferably each have a thickness of 0.5 mm to 5 mm, in particular 1 mm to 3 mm.

[0018] The electrically switchable mirror element is preferably arranged between the outer pane and the inner pane. The mirror element can be in contact with the outer pane or the inner pane, or it can be spaced apart from both.

[0019] In a first preferred embodiment of the invention, the electrically switchable mirror element is formed as a coating on one of the panes. It can be arranged on the inner surface of the outer pane or on the outer surface of the inner pane. The pane provided with the mirror element (or the mirror element applied to said pane) is connected to the other pane via at least one (preferably exactly one) bonding layer. The at least one bonding layer forms the intermediate layer of the laminated pane.

[0020] In a second preferred embodiment of the invention, the electrically switchable mirror element is designed as a film. This film is embedded in the intermediate layer of the laminated glass. It is connected to the outer glass, specifically to its inner surface, via (at least, preferably exactly) a first bonding layer, and to the inner glass, specifically to its outer surface, via (at least, preferably exactly) a second bonding layer. The at least one first and the at least one second bonding layer with the interposed mirror element form the intermediate layer of the laminated glass.

[0021] The bonding layers serve to adhesively connect the components of the composite disc between which they are arranged. The bonding layers preferably consist of one thermoplastic layer or of several thermoplastic SAINT-GOBAIN SEKURIT FRANCE 2025082-WO-PCT

[0022] Layers are formed. The thermoplastic layers can alternatively also be referred to as thermoplastic layers.

[0023] The thermoplastic layers are preferably based on polyvinyl butyral (PVB), ethylene-vinyl acetate (EVA), or polyurethane (PU), or on mixtures, copolymers, or derivatives thereof, particularly preferably on PVB. This means that the layer contains the said polymer to a large extent (proportion greater than 50 wt%). In addition to the polymer, the layer may contain other additives, such as plasticizers, UV absorbers, or stabilizers. Each thermoplastic layer is preferably formed from a thermoplastic film. The thickness of each film 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.

[0024] The bonding layers can alternatively be designed as adhesive layers. Optically clear adhesives (OCAs) are preferred. This is particularly advantageous with regard to the aesthetic appearance of the vehicle roof window. OCAs are well known to those skilled in the art. They are characterized in particular by their high optical quality. They are especially common where high optical quality is necessary, so that the adhesive layer is virtually invisible, for example, in displays or touch panels. Optically clear adhesives are characterized in particular by high light transmission and the fact that distortion-free visibility is possible. The optically clear adhesive is preferably a two-component polyurethane adhesive, a one-component acrylate adhesive, a one-component silicone adhesive, or a one-component acrylate hybrid adhesive.

[0025] In principle, a combination is also conceivable, wherein at least one bonding layer consists of at least one thermoplastic layer and at least one other bonding layer is designed as an adhesive layer.

[0026] If the mirror element is designed as a film, it can optionally be arranged in a cutout of another thermoplastic layer (capsule layer), which surrounds it like a frame. This allows thickness differences resulting from the mirror element being locally inserted between the bonding layers to be compensated for, which could otherwise lead to mechanical stresses and consequently to optical distortions or even breakage of the outer or inner pane. Between the first and second bonding layers, there is then another full-surface layer, which SAINT-GOBAIN SEKURIT FRANCE 2025082-WO-PCT

[0027] The sensor area is formed by the mirror element, and elsewhere by the capsule layer. The capsule layer and the mirror element should have the same or at least a similar thickness, with any difference in thickness preferably being no more than 0.1 mm.

[0028] The electrically switchable mirror element has a transparent state and a reflective state. The state of the mirror element can be electrically controlled, specifically by applying an electrical voltage. Therefore, the state of the mirror element depends on the applied voltage. In the transparent state, the mirror element has a lower reflectance and correspondingly a higher transmittance than in the reflective state. Conversely, in the reflective state, the mirror element has a higher reflectance and correspondingly a lower transmittance than in the transparent state. With typical mirror elements, the reflective state is present when no voltage is applied. Applying an electrical voltage causes the mirror element to switch to the transparent state.

[0029] In the transparent state, the reflectance of the mirror element is preferably less than 20% (particularly preferably less than 10%, most preferably less than 5%). In the reflective state, the reflectance of the mirror element is preferably more than 50% (particularly preferably more than 70%, most preferably more than 80%). This refers to the integrated reflectance in the spectral range from 380 nm to 780 nm, measured at an angle of 8° (to the surface normal) with light source A and a 2° detector (the 2° indicates the angle at which the light ray strikes the retina in the eye). The stated reflectance refers specifically to the surface of the mirror element facing the outer pane (outer surface), although typical mirror elements exhibit at least an approximately identical reflectance on both surfaces.

[0030] In the transparent state, the transmittance of the mirror element is preferably more than 60% (particularly preferably more than 70%, most preferably more than 80%). In the reflective state, the transmittance of the mirror element is preferably less than 50% (particularly preferably less than 30%, most preferably less than 20%). This refers to the integrated transmittance in the spectral range from 380 nm to 780 nm, measured at an angle of 0° (to the surface normal, orthogonal transmission) with light type A and a 2° detector. SAINT-GOBAIN SEKURIT FRANCE 2025082-WO-PCT

[0031] It is also conceivable that the mirror element has several different reflective states, which differ in their reflectance. Furthermore, it is conceivable that the reflectance is continuously adjustable. Crucially for the present invention, at least one transparent and at least one reflective state is present, preferably with the specified values ​​for transmittance and reflectance.

[0032] The composite pane preferably has an external reflectance of less than 20% (particularly preferably less than 10%) in the sensor area when the mirror element is in its transparent state, and an external reflectance of more than 50% (particularly preferably more than 70%) when the mirror element is in its specular state. The external reflectance is the reflectance at the outer surface of the outer pane against incident radiation. It is measured as the integrated reflectance in the spectral range from 380 nm to 780 nm at an angle of 8° (to the surface normal) using light type A and a 2° detector. The light transmission through the sensor area of ​​the composite pane is preferably at least 50% when the mirror element is transparent.

[0033] The electrically switchable mirror element has an active layer or sequence of layers that provides the reflective properties in the mirrored state and is transparent in the transparent state. This active layer or sequence of layers is arranged between a first and a second surface electrode. When the composite disc is used as intended, the surface electrodes are connected to an external voltage source, allowing an electrical voltage to be applied to the active layer or sequence of layers via the surface electrodes. The surface electrodes and the active layer are typically arranged substantially parallel to the surfaces of the outer and inner discs.

[0034] The surface electrodes are preferably transparent, which, in the context of the invention, means that they have a light transmission in the visible spectral range of at least 50%, preferably at least 70%, and particularly preferably at least 80%. The surface electrodes preferably contain at least one metal, a metal alloy, or a transparent conducting oxide (TCO). The surface electrodes can, for example, be based on silver, gold, copper, nickel, chromium, tungsten, indium tin oxide (ITO), gallium-doped or aluminum-doped zinc oxide, and / or fluorine-doped or antimony-doped tin oxide, preferably based on silver.

[0035] or ITO. The surface electrodes preferably have a thickness of 10 nm to 2 pm, particularly preferably of 20 nm to 1 pm, most preferably of 30 nm to 500 nm.

[0036] The surface electrodes are typically contacted with electrical connection cables that extend from the side edge of the composite disc and are connected to an external control unit. The electrical connection between the connection cable and the surface electrode can be made via a busbar located on the surface electrode. Such busbars can be implemented, for example, by strips of electrically conductive foil (such as copper foil) or by an electrically conductive imprint (such as silver-containing enamel).

[0037] Several variations are possible regarding the design of the active layer or layer sequence. In one embodiment, the active layer contains liquid crystals or is even based on liquid crystals. In the stress-free state, the liquid crystals exhibit, for example, a helical structure which is reflective, thus achieving the specular state. When an electrical voltage is applied, the helical structure unfolds (or twists), so that the liquid crystals no longer reflect (significantly), thus achieving the transparent state. Typically, two such active layers are present and stacked on top of each other, each reflecting in one polarization direction, with the two polarization directions of the two active layers being rotated by 90° relative to each other. In this way, reflection of light of all polarizations can be achieved.In a further embodiment, an active layer sequence is present within which the migration of hydrogen or hydrogen ions can be induced by the applied voltage. One of these layers is typically a metallic layer (for example, based on lithium or a magnesium-nickel alloy), which is reflective in its hydrogen-free metallic state, thus achieving the mirror-like state. An electrical voltage causes hydrogen to migrate into this layer, transforming it into a hydrogenated, non-metallic, and non-reflective state, thereby achieving the transparent state.

[0038] Electrically switchable mirror elements are known per se and can be purchased prefabricated, particularly as films. Prefabricated electrically switchable mirror elements based on liquid crystals in film form are commercially available (e.g., from Kent Optronics). Mirror elements in the form of a coating are also known in the field (see, e.g., AIST, Japan). SAINT-GOBAIN SEKURIT FRANCE 2025082-WO-PCT

[0039] If the mirror element is designed as a film, it comprises at least one polymeric carrier film on which the layer system consisting of the surface electrodes and the active layer (or sequence of layers) arranged between them is applied. Typically, the mirror element is a multilayer film and has two polymeric carrier films, with the layer system consisting of the surface electrodes and the active layer (or sequence of layers) arranged between the carrier films. The multilayer film then comprises, in the following order: a first carrier film – the first surface electrode – the active layer or sequence of layers – the second surface electrode – a second carrier film.The carrier films are preferably made of thermoplastic material, for example, based on polyphenylene sulfone (PPSII), polyethylene terephthalate (PET), polypropylene, polyvinyl chloride, fluorinated ethylene propylene, polyvinyl fluoride, or ethylene tetrafluoroethylene, particularly preferably based on PET. PPSII can also be particularly preferred due to its high thermal resistance, which is advantageous for the manufacturing process and processing. The thickness of the carrier films is preferably from 10 pm to 200 pm. The surface electrodes are typically provided as coatings on these carrier films.

[0040] The sensor area of ​​the composite panel is designed for the optical beam path of the transmitter and / or receiver of electromagnetic radiation. The sensor area is a locally confined region of the composite panel, designed and suitable for the optical beam path of the transmitter and / or receiver to pass through it.

[0041] The sensor area is, in particular, completely covered by the mirror element – ​​the mirror element thus completely covers the sensor area. The mirror element can also extend beyond the sensor area. For example, the mirror element can project up to 1 cm beyond the sensor area all around, preferably into an opaque masking area surrounding the sensor area.

[0042] The sensor area is typically positioned outside the central field of vision through which the driver typically observes road traffic. The mirror element preferably does not extend into this central field of vision in order to avoid obstructing the view through the laminated glass. In the case of a windshield, this central field of vision is specifically defined in ECE-R43 for vehicles. This refers to: SAINT-GOBAIN SEKURIT FRANCE 2025082-WO-PCT

[0043] The field of vision B, if the vehicle windscreen is intended for a vehicle of category M1 (vehicle for the carriage of persons with a maximum of eight seats in addition to the driver's seat); the field of vision B is defined in Annex 18 of ECE-R43; the field of vision I, if the vehicle windscreen is intended for a vehicle of category M, other than M1 (other vehicles for the carriage of persons) or for a vehicle of category N (vehicles for the carriage of goods).

[0044] In a preferred embodiment, the laminated glass pane has an opaque masking area that surrounds a central transparent viewing area in a frame-like manner, as is common in automotive windows. The masking area is thus arranged around the perimeter of the laminated glass pane. The masking area is typically formed by an opaque covering printed on a surface of the outer and / or inner pane. This covering is, in particular, made of an enamel containing glass frits and a pigment, which is screen-printed and then fired into the glass surface. Alternatively, opaque films can also be used in the intermediate layer. The frame-like masking area serves primarily to protect the adhesive used to attach the laminated glass to the vehicle body from UV radiation and to optically mask it.The light transmission of the laminated glass in the viewing area is preferably greater than 70%, at least when the laminated glass is a windshield. The term light transmission (total transmission) refers to the procedure for testing the light transmittance of motor vehicle windows as specified in ECE-R 43, Annex 3, Section 9.1. The light transmission in the masking area is less than 5%, preferably less than 2%, particularly preferably less than 0.5%, and most preferably less than 0.1% (in particular, essentially 0%).

[0045] The sensor area can be surrounded by a section of the opaque masking area, as is common with windshields. This section of the masking area can, for example, be adjacent to, and extend along, the section of the frame-like masking area that corresponds to the upper edge of the laminated glass (roof edge) when installed, pointing upwards or towards the vehicle roof. The section of the masking area around the sensor area thus extends from the section corresponding to the upper edge towards the center of the glass. SAINT-GOBAIN SEKURIT FRANCE 2025082-WO-PCT

[0046] In an advantageous embodiment, the sensor area is surrounded by an opaque masking area (or by a section of the opaque masking area), and the side edges of the mirror element as well as the electrical connections of the mirror element are arranged within the masking area. The side edge and the connections are concealed by the masking area, which is advantageous with regard to an aesthetically pleasing appearance. The mirror element thus extends beyond the sensor area into the surrounding masking area.

[0047] In preferred embodiments of the invention, the transmitter and / or receiver of electromagnetic radiation is:

[0048] - a camera for the visible or infrared spectral range,

[0049] - a lidar module (light detection and ranging) or radar module (radio detection and ranging),

[0050] - a TOF sensor (time of flight),

[0051] - an optical rain sensor or

[0052] - a light sensor,

[0053] - an optical data interface, for example a receiver for optical (especially IR-based) data communication.

[0054] Cameras, lidar or radar modules or TOF sensors are particularly preferred because, due to their comparatively complex electronics, they are especially sensitive to overheating, which is why the invention can unfold its advantages to a particularly high degree.

[0055] The transmitter and / or receiver preferably comprises at least one receiver of electromagnetic radiation, as is the case with the elements listed above. It may also include a transmitter of electromagnetic radiation, as in lidar or radar modules, where radiation is emitted by a transmitter and the radiation reflected back from the objects being measured is detected by a receiver, or in a bidirectional optical data interface. However, the invention can also be implemented with transmitters of electromagnetic radiation alone. Examples include lighting devices, displays, or transmitters for optical (especially IR-based) data communication as an optical data interface.

[0056] The transmitter and / or receiver is located on the inside side of the laminated glass pane and attached to the inner pane. The beam path of the transmitter and / or receiver runs SAINT-GOBAIN SEKURIT FRANCE 2025082-WO-PCT

[0057] through the laminated glass, from the interior to the external environment. The area of ​​the laminated glass through which the beam path passes is referred to as the sensor area for the purposes of the invention. The sensor area lies between the exposed interior surface of the inner glass and the exposed exterior surface of the outer glass.

[0058] In the case of a windshield, the transmitter and / or receiver is directed forward through the laminated glass (relative to the intended direction of travel when driving forward). The transmitter and / or receiver can therefore emit electromagnetic radiation forward through the laminated glass and / or detect electromagnetic radiation from a space in front of the vehicle through the laminated glass. In the case of a rear window, the transmitter and / or receiver is directed backward through the laminated glass (relative to the intended direction of travel when driving forward). The transmitter and / or receiver can therefore emit electromagnetic radiation backward through the laminated glass and / or detect electromagnetic radiation from a space behind the vehicle through the laminated glass.

[0059] The angle of the beam path from the transmitter and / or receiver to the composite lens can be called the angle of incidence. It is determined as the angle between the surface normal of the composite lens on the one hand and the beam path between the composite lens and the transmitter / receiver on the other. When the beam path is perpendicular to the composite lens, the angle of incidence is 0°. Such an angle of incidence of 0° or a few degrees can occur, for example, in trucks and buses whose windows are installed at a very steep angle. Particularly in passenger cars, the windows are typically installed with a pronounced inclination; in the case of a windshield, usually with an installation angle (measured from the vertical) of approximately 60°. This would result in an angle of incidence of 60° if the transmitter and / or receiver were oriented horizontally forward.If the beam path is inclined slightly downwards towards the roadway, even greater angles of attack result.

[0060] The transmitter and / or receiver is attached to the laminated glass, in particular to the exposed interior surface of the inner pane. For this purpose, the transmitter and / or receiver can, for example, be arranged in a housing that is bonded to the laminated glass. For windshields, so-called "brackets" are particularly common, and this is also preferred in the present case. A bracket is a mounting device that is attached to the laminated glass, in particular SAINT-GOBAIN SEKURIT FRANCE 2025082-WO-PCT.

[0061] The bracket is attached to the device and serves as a mounting point for the transmitter and / or receiver. It is often designed as a combined mounting device for multiple functional elements, the position and relative distance of which are determined by the bracket. This multiple elements can consist of several transmitters and / or receivers of electromagnetic radiation, such as a camera, a lidar module, and a light and / or rain sensor. The housing or bracket is typically black, especially when made of black plastic. It therefore has a comparatively high heat absorption rate, which further increases the risk of the transmitter and / or receiver overheating.

[0062] The outer and inner panes can each be formed in one piece. However, it is also possible for the outer and / or inner pane to have a feedthrough in which the sensor area is arranged, or through which the sensor area, and thus the beam path of the transmitter and / or receiver, passes. An insert is arranged in the feedthrough. According to the invention, the insert is part of the pane in question, which is then formed in multiple parts and comprises the pane with the feedthrough and the insert therein. Such an insert can be advantageous for providing the sensor area with higher light transmission by selecting an insert that has a higher light transmission than the surrounding rest of the pane.The insert is essentially a small glass or plastic disc with the same or a slightly smaller surface area as the feedthrough, which is inserted into the feedthrough. The insert is also connected to and secured by the thermoplastic intermediate layer. The thickness of the insert can correspond to the thickness of the disc into which it is inserted – but it can also be thinner or thicker than the disc.

[0063] In an advantageous embodiment, the outer pane, the inner pane, and the intermediate layer are clear and untinted, at least in the sensor area. This can be achieved by making the outer pane, the inner pane, and the intermediate layer entirely clear and untinted. If, on the other hand, the outer pane, the inner pane, and / or the intermediate layer are tinted or colored, it can be designed with a feedthrough in which the sensor area is arranged and into which a clear and untinted insert is placed.

[0064] The following configurations are particularly preferred: SAINT-GOBAIN SEKURIT FRANCE 2025082-WO-PCT

[0065] 1. The outer and inner panes are made of clear glass, preferably ultra-clear glass, and in particular each as a single piece. The intermediate layer is also entirely clear and untinted.

[0066] 2. The outer pane is made of clear glass, preferably ultra-clear glass, particularly as a single piece. The inner pane is made of tinted or colored glass and has a feedthrough in which the sensor area is arranged, with an insert being arranged in the feedthrough. The insert is made of clear glass, preferably ultra-clear glass, or a clear plastic. The intermediate layer is either entirely clear and untinted or clear and untinted in the sensor area and tinted or colored in the surrounding areas. Such an intermediate layer can, for example, be produced from a tinted or colored thermoplastic film into which a feedthrough is formed in which the sensor area is arranged, with a clear and untinted film being inserted into the feedthrough.

[0067] In principle, it is also conceivable that the outer pane is tinted or colored and made clear and untinted by an insert in the sensor area. Such a multi-piece outer pane could be used in conjunction with a single-piece clear and untinted inner pane, or in conjunction with a multi-piece inner pane with a clear and untinted insert. However, such a multi-piece outer pane is less preferred because it would impair the external appearance of the laminated glass and dirt could accumulate between the insert and the surrounding outer pane.

[0068] Clear glass refers to untinted and uncolored glass. Ultra-clear glass is particularly low in iron and therefore exceptionally transparent. Ultra-clear glass typically has a light transmission of more than 90%.

[0069] The laminated glass can be provided with an IR-reflective coating. Such coatings are commonly used as sun protection coatings. The IR-reflective coating is suitable for reflecting portions of solar radiation in the near-infrared range, thus reducing the heating of the vehicle interior. By means of an electrical contact, allowing an electric current to be passed through the IR-reflective coating, the coating can also be used as a heated coating to defrost the laminated glass or remove condensation. The IR-reflective coating can be applied, for example, to the inner surface of the outer pane, to the outer surface of the inner pane, or to a carrier film within the intermediate layer. To ensure the operation of the SAINT-GOBAIN SEKURIT FRANCE 2025082-WO-PCT

[0070] To avoid interfering with the transmitter and / or receiver, the IR-reflective coating is preferably not present in the sensor area. Since the transmitter and / or receiver is then not thermally shielded by the IR-reflective coating, the invention unfolds its advantages to a particular degree, especially with a clear and untinted sensor area. The sensor area can be excluded from the coating, for example, by a suitable aperture or by masking techniques. Alternatively, it is conceivable that the coating is first applied over the entire surface and then subsequently removed from the sensor area, for example, by laser ablation.

[0071] Such an IR-reflective coating is typically a thin-film stack comprising at least one electrically conductive layer, in particular at least one silver layer. In addition to the at least one silver layer, dielectric layers or sequences of layers are typically present. The IR-reflective coating comprises n metallic layers, in particular silver layers, and (n+1) dielectric layers (or sequences of layers), wherein the dielectric layers (or sequences of layers) and the metallic layers are arranged alternately, such that each metallic layer is positioned between two dielectric layers (or sequences of layers), and a layer (or sequence of layers) is positioned between adjacent metallic layers. The number n is a natural number greater than or equal to 1 (n>1).Common dielectric layers include, for example, anti-reflective coatings, which reduce the reflection of visible light and thus increase the transparency of the coated disk (e.g., based on silicon nitride, silicon-metal mixed nitrides such as silicon zirconium nitride, titanium oxide, aluminum nitride or tin oxide), matching layers, which improve the crystallinity of the electrically conductive layer (e.g., based on zinc oxide) and smoothing layers, which improve the surface structure for the layers above (e.g., based on non-crystalline tin-zinc mixed oxide).

[0072] The solar control coating is preferably applied to the entire surface of the glass, with the exception of the sensor area, any other local areas intended to act as data transmission windows to ensure the transmission of electromagnetic radiation through the windshield, and a surrounding edge area. The uncoated area may also extend slightly beyond the sensor area, for example, by up to 1 cm all around. The surrounding uncoated edge area has a width of up to 20 cm, for example. It prevents direct contact between the solar control coating and the surrounding atmosphere, thus protecting the solar control coating inside the laminated glass from corrosion and damage. SAINT-GOBAIN SEKURIT FRANCE 2025082-WO-PCT

[0073] is protected. Preferably, at least 80% of the glass surface is coated with the sun protection coating.

[0074] The IR-reflective coating is preferably arranged on the inner surface of the outer pane or the outer surface of the inner pane. It can also be applied to a carrier film which is embedded in the intermediate layer, in particular between two bonding layers.

[0075] Regarding the arrangement of the IR-reflecting coating and mirror element, the following variants are preferred:

[0076] - IR-reflective coating and mirror element on the interior surface of the outer pane;

[0077] - IR-reflective coating on the interior surface of the outer pane, mirror element embedded in an intermediate layer;

[0078] - IR-reflective coating on the interior surface of the outer pane, mirror element on the exterior surface of the inner pane;

[0079] - IR-reflective coating embedded in an intermediate layer, mirror element on the interior surface of the outer pane;

[0080] - IR-reflective coating and mirror element embedded in an intermediate layer;

[0081] - IR-reflective coating embedded in an intermediate layer, mirror element on the outer surface of the inner pane;

[0082] - IR-reflective coating on the outer surface of the inner pane, mirror element on the inner surface of the outer pane;

[0083] - IR-reflective coating on the outer surface of the inner pane, mirror element embedded in an intermediate layer;

[0084] - IR-reflective coating and mirror element on the outer surface of the inner pane.

[0085] If the mirror element and the IR-reflective coating are arranged on the same surface of one of the panes, the mirror element preferably completely covers the area not coated and overlaps the coating. Preferably, the IR-reflective coating is arranged in the overlap area below the mirror element, i.e., closer to the pane surface. If the mirror element and the IR-reflective coating are embedded in the intermediate layer, they are preferably arranged in the same plane. This can be achieved by providing the IR-reflective coating on a carrier film into which a feedthrough is created.

[0086] The foil-like mirror element is inserted into this assembly, preferably with a precise fit. The resulting foil arrangement is positioned between two bonding layers. However, it is also possible for the mirror element and the IR-reflecting coating to be arranged in different planes, with, for example, another bonding layer between them.

[0087] In an advantageous embodiment of the invention, the mirror element is divided into a plurality of independently switchable segments. For this purpose, at least one surface electrode is divided into at least two separate electrode segments by at least one insulating line. Each electrode segment is electrically connected to its own (or separate) current busbar. Each electrode segment of said surface electrode and the opposite surface electrode are electrically connected to the voltage source, so that an electrical voltage can be applied independently between each electrode segment of said surface electrode and the opposite surface electrode in order to control the optical properties of the intervening section of the active layer / layer sequence.This allows for the realization of multiple independent switching areas, whose optical properties can be electrically controlled independently. The isolation line can also be integrated into both surface electrodes, into one surface electrode and the active layer, or into both surface electrodes and the active layer to achieve improved electrical isolation. The isolation line is preferably generated by laser radiation and has, for example, a width of 5 pm to 500 pm, particularly 20 pm to 200 pm. With such a segmented mirror element, individual areas can be switched to a partially or fully reflective state, for example, to prevent local overload of the transmitter and / or receiver.

[0088] The laminated glass can be flat, as is the case, for example, with vehicle windows for buses, trains, or tractors. In an advantageous embodiment, however, the laminated glass is curved (especially spherically), as is common for automotive windows. Typical radii of curvature range from approximately 10 cm to approximately 40 m.

[0089] The composite disc can be manufactured by stacking the individual layers in the specified sequence into a layer stack and then laminating them together. For this purpose, known methods can be used. SAINT-GOBAIN SEKURIT FRANCE 2025082-WO-PCT

[0090] Examples of bonding processes include 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 intermediate layer typically occurs under the influence of heat, vacuum, and / or pressure.

[0091] The invention further comprises an arrangement comprising the composite disk according to the invention and a control unit which is connected to the mirror element of the composite disk and a voltage source and is suitable for applying an electrical voltage to the mirror element, wherein the mirror element is switched from a reflective to a transparent state.

[0092] The invention also comprises a vehicle equipped with said arrangement. The vehicle is in particular equipped with

[0093] - a composite disc according to the invention,

[0094] - a control unit which is connected to the mirror element and the vehicle's electrical system and is suitable for applying an electrical voltage to the mirror element, whereby the mirror element is switched from a reflective to a transparent state.

[0095] The vehicle can be any means of transport for air, water, or land traffic. It is preferably a motor vehicle, in particular a passenger car. The laminated glass is preferably the windshield, side window, or rear window of the vehicle.

[0096] The invention also comprises a method for operating the mirror element of a vehicle according to the invention, wherein

[0097] - the control unit applies an electrical voltage to the mirror element when the vehicle's electrical system is activated or when the engine is started, in order to switch it into a transparent state,

[0098] - the control unit interrupts the electrical voltage when the engine is switched off or the vehicle's electrical system is deactivated, in order to switch the mirror element to a reflective state. SAINT-GOBAIN SEKURIT FRANCE 2025082-WO-PCT

[0099] Activating the vehicle's electrical system refers to the process of switching the vehicle on and putting it into an operational state – in classic vehicles, for example, by turning the ignition key, and in modern vehicles often by contactless recognition of the "vehicle key" or by pressing a switch or button. The control unit then applies an electrical voltage to the mirror element, which changes the mirror element from its de-energized, reflective state (especially its fully reflective state) to a transparent state. The transmitter and / or receiver of electromagnetic radiation can then function through the transparent sensor area during vehicle operation. The mirror element remains in its transparent state during operation.When the vehicle is parked and the engine is switched off or the on-board electrical system is put into standby mode, the voltage is interrupted and the voltage-free mirror element is in the reflective state (especially the fully reflective state).

[0100] The fully reflective state refers to the state of the mirror element with minimum light transmission and maximum reflectance. Typical mirror elements are not only switchable between the transparent and fully reflective states, but can also be continuously adjusted, allowing for the realization of intermediate, partially reflective states. In comparison to the transparent state, partially reflective states are characterized by reduced light transmission and increased reflectance, without, however, reaching maximum reflectance.

[0101] In an advantageous further development of the method, the control unit is capable of detecting an overload of the transmitter and / or receiver, i.e., an excessively high signal strength. If such an overload is detected, the electrical voltage applied to the mirror element is reduced to switch the mirror element into a partially reflective state in which no overload occurs. If a reduced signal strength is detected, so that there is no longer a risk of overload, the mirror element is switched back to the transparent state.

[0102] In an advantageous further development of the method, the control unit is capable of detecting local overdriving. Such local overdriving can occur, for example, in a camera when a vehicle is recorded with its headlights switched on, whereby the areas of the camera chip exposed to the headlight radiation are overdriven, while no overdriving occurs in other areas. The mirror element is divided into a plurality of independently switchable segments. SAINT-GOBAIN SEKURIT FRANCE 2025082-WG-PCT

[0103] as described above. Upon detection of local overload, the control unit reduces the electrical voltage at one or more segments to switch the affected segment(s) to a semi-reflective or fully reflective state in which the local overload does not occur. If a reduced signal strength is detected, such that there is no longer a risk of local overload, the affected segment(s) are switched back to the transparent state. SAINT-GOBAIN SEKURIT FRANCE 2025082-WO-PCT

[0104] 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.

[0105] They show:

[0106] Fig. 1 shows a top view of an embodiment of the composite disc according to the invention, Fig. 2 shows a cross-section through the composite disc and arrangement from Figure 1.

[0107] Fig. 3 shows a cross-section through an area of ​​the composite disc from Figures 1 and 2, Fig. 4 shows a cross-section through an area of ​​a further embodiment of the composite disc according to the invention.

[0108] Figures 1 and 2 each show a detail of a composite glass pane according to the invention. The composite glass pane is the windshield of a passenger car. It is formed from an outer pane 1 and an inner pane 2, which are bonded together via a thermoplastic intermediate layer 3.

[0109] The outer pane 1 faces the outside environment when installed. It is made of soda-lime glass with a thickness of, for example, 2.1 mm. It has an outer surface I and an inner surface II. The inner pane 2 faces the vehicle interior when installed. It is made of soda-lime glass with a thickness of, for example, 1.6 mm. It has an outer surface III and an inner surface IV. The intermediate layer 3 consists of a 0.76 mm thick PVB film. The outer pane 1 and the inner pane 2 are bonded together via the intermediate layer 3.

[0110] The windshield has a transparent viewing area D and an opaque masking area M, which surrounds the viewing area D in a frame-like manner.

[0111] An electromagnetic transmitter and / or receiver 4 is attached to the inner surface IV of the inner pane 2 by means of a mounting device 5, a so-called bracket. The transmitter and / or receiver 4 is a camera which is directed forward in the direction of travel. The camera's beam path L passes through a sensor area S of the laminated glass. SAINT-GOBAIN SEKURIT FRANCE 2025082-WO-PCT

[0112] To protect the transmitter and / or receiver 4 from overheating, for example when the vehicle is parked in strong sunlight, the laminated glass in the sensor area S is equipped with an electrically switchable mirror element, which is not shown in the figure.

[0113] Figure 3 shows an enlarged cross-section of an area of ​​the composite glass pane of Figures 1 and 2, without the transmitter and / or receiver 4. The masking area M is formed by a black cover print 6 on the interior surface II of the outer pane. It is arranged in a frame-like manner in an edge region of the windshield. A section of the masking area M also surrounds the sensor area S.

[0114] An IR-reflective coating 30 is arranged on the outer surface III of the inner pane 2. It serves as a solar control coating and reflects IR components of solar radiation to reduce the thermal energy input through the laminated pane. To avoid interfering with the operation of the transmitter and / or receiver 4, the IR-reflective coating 30 is removed in the sensor area S.

[0115] The outer pane 1 and inner pane 2 are made of clear glass to ensure optimal transmission of the signal from the transmitter and / or receiver 4. Furthermore, the sensor area S lacks the thermal shielding provided by the IR-reflective coating 30. Therefore, the transmitter and / or receiver 4 can heat up considerably due to sunlight, which can damage its electronic components. This is particularly likely when the vehicle is parked and neither airflow nor the onboard climate control system is providing cooling. To prevent overheating, the laminated glass is equipped with the electrically switchable mirror element 7, which covers the entire sensor area S.

[0116] During driving, the mirror element 7 is supplied with an electrical voltage via a control unit, causing it to be in a transparent state. When the vehicle is parked, no voltage is applied to the mirror element 7, and it is in a reflective state, whereby the visible components of solar radiation are largely reflected back outwards and do not contribute to heating the transmitter and / or receiver 4. This protects the transmitter and / or receiver 4 from overheating.

[0117] The mirror element 7 is arranged as a coating directly on the interior surface II of the outer pane 1. It completely covers the sensor area S and overlaps SAINT-GOBAIN SEKURIT FRANCE 2025082-WO-PCT

[0118] with the opaque cover print 6, so that the side edges and electrical connections of the mirror element 7 are located in the masking area M and are thereby concealed.

[0119] Figure 4 shows an enlarged cross-section of a region of a further embodiment of the composite disc according to the invention. The inner disc 2 has a through-hole through which the sensor region S extends. An insert 9 is inserted into this through-hole.

[0120] The insert is made of ultra-clear glass, for example. This design is particularly suitable if the inner pane 2 has a slight coloration or tint, such as a green tint. Since colored glass would impair the function of the transmitter and / or receiver 4, the clear insert 9 is used in the sensor area S.

[0121] The IR-reflective coating 30 and the mirror element 7 are embedded in the intermediate layer 3. The IR-reflective coating 30 is provided on a carrier film. A feedthrough is incorporated into this film, through which the sensor area S runs. The mirror element 3 is designed as a multilayer film and is precisely fitted into the feedthrough of the carrier film. This film assembly is connected to the outer pane 1 via a first thermoplastic layer 3.1 and to the inner pane 2 via a second thermoplastic layer 3.2. SAINT-GOBAIN SEKURIT FRANCE 2025082-WO-PCT

[0122] Reference symbol list:

[0123] (1) Outer pane

[0124] (2) Inner disc

[0125] (3) Intermediate layer

[0126] (3.1) first thermoplastic layer of the intermediate layer 3 (3.2) second thermoplastic layer of the intermediate layer 3 (4) transmitter and / or receiver

[0127] (5) Fastening device

[0128] (6) Cover printing

[0129] (7) Electrically switchable mirror element

[0130] (9) deployment

[0131] (30) IR-reflective coating

[0132] (L) Beam path of the transmitter and / or receiver 4 (S) Sensor area of ​​the composite disc

[0133] (I) outer surface of the outer pane 1

[0134] (II) Interior surface of the outer pane 1 (III) Exterior surface of the inner pane 2

[0135] (IV) interior surface of the inner pane 2

[0136] (D) Windscreen viewing area

[0137] (M) Windscreen masking area

[0138] XX' Intersection line

Claims

1. SAINT-GOBAIN SEKURIT FRANCE 2025082-WO-PCT Patent claims 1. Laminated glass for a vehicle, comprising an outer pane (1) with an outer surface (I) and an inner surface (II) and an inner pane (2) with an outer surface (III) and an inner surface (IV), wherein the inner surface (II) of the outer pane (1) and the outer surface (III) of the inner pane (2) are connected to each other via an intermediate layer (3), wherein a transmitter and / or receiver (4) of electromagnetic radiation is attached to the interior surface (IV) of the inner pane (2), the optical beam path of which passes through a sensor area (S) of the composite pane, wherein the composite pane is equipped in the sensor area (S) with an electrically switchable mirror element (7).

2. Composite pane according to claim 1, wherein the electrically switchable mirror element (7) is arranged as a coating on the interior surface (II) of the outer pane (1) or the exterior surface (III) of the inner pane (2).

3. Composite disc according to claim 1, wherein the electrically switchable mirror element (7) is embedded as a film in the intermediate layer (3).

4. Composite disc according to one of claims 1 to 3, wherein the electrically switchable mirror element (7) has an active layer or sequence of layers between two surface electrodes and wherein - the active layer contains liquid crystals whose configuration is influenced by the applied electrical voltage, thereby realizing the transparent and the reflective state of the mirror element (3), or - the active layer sequence contains a metallic layer and the applied electrical voltage induces a migration of hydrogen ions in the layer sequence, so that the metallic layer is in a metallic state in the mirrored state of the mirror element (3) and in a hydrogenated state in the transparent state of the mirror element (3).

5. Composite disc according to any one of claims 1 to 4, wherein the reflectance of the mirror element (7) in the spectral range from 380 nm to 780 nm is less than 20% in a transparent state and more than 50% in a reflective state, SAINT-GOBAIN SEKURIT FRANCE 2025082-WO-PCT determined as integrated reflectance in the spectral range from 380 nm to 780 nm at an angle of 8° to the surface normal with light type A and a 2° detector.

6. Composite disc according to one of claims 1 to 5, wherein the transmitter and / or receiver (4) is a camera for the visible or infrared spectral range, a lidar module or radar module, a TOF sensor, an optical rain sensor, a light sensor or an optical data interface.

7. Composite disc according to one of claims 1 to 6, wherein the outer disc (1), the inner disc (2) and the intermediate layer (3) are clear and untinted at least in the sensor area (S).

8. Composite disc according to one of claims 1 to 7, which is provided with an IR-reflecting coating (30) which is not present in the sensor area (S).

9. Composite disc according to one of claims 1 to 8, wherein the sensor area (S) is surrounded by an opaque masking area (M) in which the side edges and the electrical connections of the mirror element (7) are arranged, wherein the masking area (M) has a light transmission of less than 5%.

10. Composite disc according to one of claims 1 to 9, wherein the mirror element (7) is divided into a plurality of independently switchable segments.

11. Composite glass according to any one of claims 1 to 10, which is a windshield, side window or rear window of a motor vehicle, in particular a passenger car.

12. Vehicle, equipped with - a composite disc according to one of claims 1 to 11, - a control unit which is connected to the mirror element (7) and the vehicle's electrical system and is suitable for applying an electrical voltage to the mirror element (7), whereby the mirror element (7) is switched from a reflective to a transparent state.

13. Method for operating the mirror element (7) of a vehicle according to claim 12, wherein SAINT-GOBAIN SEKURIT FRANCE 2025082-WO-PCT - the control unit applies an electrical voltage to the mirror element (7) when the on-board electrical system is activated or when the engine is started, in order to switch it into a transparent state, - the control unit interrupts the electrical voltage when the engine is switched off or when the on-board electrical system is deactivated in order to switch the mirror element (7) into a reflective state.

14. Method according to claim 13, wherein the control unit is suitable for detecting an overdrive of the transmitter and / or receiver (4), and wherein, in the event of a detected overdrive, the control unit reduces the electrical voltage in order to switch the mirror element (7) into a partially reflective state in which no overdrive occurs.

15. Method according to claim 13 or 14, wherein the control unit is suitable for detecting a local overdrive of the transmitter and / or receiver (4), and wherein the mirror element (7) is divided into a plurality of independently switchable segments, and wherein, in the event of a detected local overdrive, the control unit reduces the electrical voltage at one or more segments in order to switch the segment(s) concerned to a partially reflective or fully reflective state in which the local overdrive does not occur.

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