Selectively heatable vehicle pane assembly

Abstract

The invention relates to a vehicle pane assembly (100), having - at least one composite pane (1) with a first exterior-side pane (2), a second interior-side pane (3), and at least one thermoplastic intermediate layer (4) between the first and second pane, - at least one sensor (5) which is mounted in the interior and emits and / or receives beams through the at least one pane (1) in a passage region (6) in order to detect information about exterior conditions, the passage region for the beams (6) forming only a sub-region of the pane (1), and - at least one narrow-band radiation source (7) for radiation (8) in the IR wavelength range of A = 1.3 µm to 3.5 µm in order to clear the passage region (6) of water-based condensation, the radiation source (7) being situated so as to be connected to the composite pane (1) in such a way that the IR radiation (8) emitted by the radiation source (7) is coupled into the composite pane (1) in an entry region. The vehicle pane assembly is characterized in that at least one decoupling element (9) for the IR radiation of the radiation source (7) is provided in the passage region (6) for the sensor beams. The invention also relates to a method for producing such a vehicle pane assembly and to the use thereof.

Description

[0001] Selectively heated vehicle window arrangement

[0002] The invention relates to a selectively heated vehicle window arrangement, a method for manufacturing such a vehicle window arrangement, and its use.

[0003] One challenge in driving is heating vehicle windows to prevent icing or fogging, which impairs visibility. This obstruction also affects areas of the window used by sensors inside the vehicle for environmental monitoring. Window heating is typically achieved by blowing heated air onto the window through inlets. This type of heating is collectively known as Heating, Ventilation and Air Conditioning (HVAC). Besides its enormous energy consumption, the inlets that transport the hot air and blow it onto the window require considerable space. Furthermore, the outlet nozzles must be positioned in a specific geometric relationship to the window, which significantly limits design and construction freedom.Therefore, this standard heating method is not well suited for selectively clearing the sensor's field of view from a pane of glass. Furthermore, this type of heating is comparatively slow.

[0004] Heated vehicle windows are well-known. They are primarily used as heated windshields in motor vehicles and offer the convenience of clearing the windshield of ice or condensation by heating it. They feature transparent, electrically conductive coatings, particularly silver layers. These coatings are electrically contacted, allowing an electric current to pass through them. This heats the coating, which is the basis of the heating effect. For example, see WO2013 / 104438A1.

[0005] A common problem with electrically conductive coatings is their high surface resistance, which, especially with large dimensions of the windscreen to be heated or with long current paths, necessitates a high operating voltage—in any case, higher than the usual vehicle on-board voltages. WO 2013 / 104439 A1 and EP 2803246 B1 disclose an electrically conductive coating for heating a windscreen, which consists of different layers that can somewhat reduce the surface resistance. Furthermore, heat loss, and thus energy loss, through convection across the usually large windscreen surfaces is also very high. Another disadvantage of heated coatings is that, for example, silver layers are not permeable to high-frequency radiation. This impairs, for example, the reception of mobile phone signals, communication with cloud servers ("Internet of Things"), and similar applications.This can lead to problems, especially in the case of electric vehicles. Some vehicle manufacturers, particularly electric vehicle manufacturers, therefore reject the use of silver-containing coatings.

[0006] Another challenge with often multi-layered, electrically conductive coatings used for heating vehicle windows is achieving an aesthetically pleasing appearance, as well as meeting required standards, for example, regarding light transmission and color neutrality, especially for windshields, but also rear windows or side windows. Furthermore, selectively heating a sensor's field of view with this heating arrangement would entail considerable manufacturing effort, as the heating layer(s) would have to be precisely integrated into the window within the sensor's field of view.

[0007] If the vehicle windshield is a laminated glass unit, thermal radiation can also be used to prevent fogging or icing. JP2013001611A discloses a laminated glass unit with an IR-absorbing interlayer. Irradiating the laminated glass unit with IR radiation causes it to heat up through the absorbing interlayer, thus reducing fogging or icing. However, this also presents another problem: the absorbing interlayer heats up locally and may expand, potentially leading to breakage of the glass panes within the laminated glass unit.

[0008] FR960125A and US20110067726A1 show laminated windshields with IR radiation sources. If water droplets or frost are present on the windshield, it can be irradiated with the IR radiation source, causing any aqueous film on the windshield to evaporate.

[0009] W02024083807A1 discloses a heated composite disc comprising an outer disc and an inner disc connected to each other via a thermoplastic intermediate layer, and at least one heating device, wherein the heating device is a radiation source in the IR wavelength range of A = 1.3 pm to 3.5 pm and is arranged such that IR radiation in the wavelength range of A = 1.3 pm to 3.5 pm is coupled into the outer disc and / or inner disc.

[0010] W02013131700A1 discloses a disc arrangement with a heated scattering aperture, which makes it possible to heat an area of ​​a disc.

[0011] DE102011103340A1 discloses a device for a vehicle, which is arranged in the vehicle interior behind a vehicle window, comprising a housing and at least one optical sensor system, with a viewing direction towards and / or through an area of ​​the vehicle window, wherein the device comprises at least one active light source, by means of which electromagnetic radiation is emitted onto at least a part of the area of ​​the vehicle window through or towards which the at least one optical sensor system looks, for heating the at least a part of the area of ​​the vehicle window.

[0012] Therefore, there is a general need for improved vehicle windows that can be cleared of water deposits that obstruct vision, and in particular for those that allow for the selective clearing of a sensor viewing area. Water can appear, for example, as a deposit of condensed moisture, in droplet form, or as ice. Specifically, there is a need for a heating system that is also suitable for selectively clearing sensor viewing areas in vehicle glazing, has high efficiency, achieves rapid ice and fog removal, poses no risk of local breakage of the laminated glass, and requires no complex modifications to the window.

[0013] The present invention therefore aims to provide such an improved, particularly effective, fast-acting, and energy-efficient vehicle windshield assembly that can be selectively heated in the sensor's field of view, has an aesthetically pleasing appearance, and also meets the requirements of necessary standards such as light transmission and color neutrality. The vehicle windshield assembly should be simple and inexpensive to manufacture and minimize the risk of breakage of the glass panes in a laminated windshield due to strong local temperature differences. Furthermore, the invention aims to provide a method for manufacturing such a vehicle windshield assembly and for its use.

[0014] These and other problems of the present invention are solved according to the invention by a vehicle disc arrangement according to claim 1, a method according to claim 11, and a use according to claim 12. Preferred embodiments are described in the dependent claims.

[0015] The selectively heated vehicle window arrangement according to the invention comprises at least one laminated glass pane with an outer first pane, an inner second pane, and at least one thermoplastic intermediate layer arranged between the first and second panes; at least one inner-side sensor which emits and / or receives radiation through the laminated glass in a transmission area to detect information about the conditions of the outside environment, wherein the transmission area for the radiation forms only a partial area of ​​the pane; and at least one narrowband radiation source for radiation in the IR wavelength range of 1.3 pm to 3.5 pm for removing water-based condensation from the transmission area, wherein the radiation source is arranged to be connected to the laminated glass pane in such a way that the IR radiation emitted by the radiation source is coupled into the laminated glass pane in an entry area.wherein at least one coupling element for the IR radiation of the radiation source is arranged in the passage area of ​​the sensor beams.

[0016] In the context of the invention, "interior-mounted sensor" means that, when the vehicle windscreen assembly is installed in a vehicle, the sensor is mounted on a surface of the laminated windscreen facing the vehicle interior. Preferably, the sensor is mounted on the surface of the second windscreen facing away from the thermoplastic interlayer. It is understood that the sensor does not necessarily have to be mounted directly on a surface of the laminated windscreen facing the vehicle interior, but can, for example, also be arranged in a housing that is mounted on the surface of the laminated windscreen facing the vehicle interior.

[0017] According to the invention, "selectively heated" means that the laminated glass of the vehicle windscreen assembly can be cleaned, in particular of water-based deposits such as ice and / or condensed moisture, in the area through which the sensor beams pass. This is achieved according to the invention by an active heating effect using the IR radiation in the wavelength range of 1.3 pm to 3.5 pm. IR radiation in a wavelength range of 1.3 pm to 3.5 pm is coupled into the laminated glass by the radiation source. The laminated glass is inherently suitable as an optical waveguide to direct the IR radiation by utilizing total internal reflection. However, an IR-conducting structure can also be provided in the laminated glass. The first and / or the second glass is particularly preferably an IR-conducting structure.

[0018] If water is present on the disc in the sensor radiation's transmission area, for example as condensation or ice, the IR radiation can be selectively coupled out by the coupling element in these water-covered areas. This results in improved and more effective absorption of the IR radiation and excitation of water molecules in ice crystals and water droplets by the IR radiation, compared to passive coupling of the water (i.e., coupling solely due to the change in refractive index between air and water). This causes the ice to melt very quickly and the water to evaporate very rapidly. Advantageously, energy loss due to convection is largely avoided.

[0019] Furthermore, by incorporating an output coupling element, compared to previously known solutions with passive output coupling (i.e., solely through changes in the refractive index), the coupling of IR radiation at a location other than the desired transmission area of ​​the sensor radiation is avoided. This prevents losses and renders other measures, such as the use of IR-reflective coatings to reflect IR rays back at the edges of the disk, obsolete.

[0020] The first pane of the laminated glass has a first outer surface I (side I) and a second, inner surface II (side II). The first surface is designed to face the outside environment when the vehicle window assembly is installed in a vehicle and is also called the outer surface. The second surface is designed to face the vehicle interior when the vehicle window assembly is installed in a vehicle and is also called the inner surface. Accordingly, the second pane of the laminated glass has a second outer surface III (side III) and a second inner surface IV (side IV).

[0021] The vehicle window assembly is designed to separate the interior from the external environment within a vehicle window opening. It is particularly preferably the windshield of a passenger car or truck. In a particularly advantageous embodiment, the vehicle is an electric vehicle. The laminated glass of the vehicle window assembly can have conventional coatings, prints (for example, conventional enamel overprints), and other elements.

[0022] A major advantage of the invention is that it eliminates the need for electrically heated layers, such as silver layers or IR absorption layers, specifically applied only in the sensor's penetration area. This reduces the risk of glass breakage. Furthermore, the IR radiant heating system with active extraction according to the invention does not impair the transmission of high-frequency radiation, for example, for receiving mobile phone signals, communicating with cloud servers ("Internet of Things"), and similar applications, resulting in further advantages. A particularly significant advantage of the invention is that the described heating effect is very fast and effective, selectively targeting the penetration area. Defrosting or fogging in this area can thus be achieved in under 60 seconds, for example, in approximately 30 seconds.At the same time, the risk of breakage of the glass in the laminated pane is reduced compared to other previously known variants of selective heating, since heating with IR radiation generates significantly less large, localized temperature differences in the glass.

[0023] Preferably, the radiation source is rigidly connected to the composite disk. In the context of the invention, the fact that the radiation source is rigidly connected to the disk further means that the radiation source is arranged such that its position relative to the optical waveguide (disc) does not change even when the composite disk is moved.

[0024] In a preferred embodiment, the sensor is a camera or an IR sensor, and in particular a lidar sensor.

[0025] In a further embodiment, the narrowband IR radiation source is a halogen lamp with a band filter, an LED, an OLED or a laser diode, preferably an LED.

[0026] For the purposes of the invention, a narrowband IR radiation source is understood to be one that has a full width at half maximum (FWHM) within a wavelength range of less than 400 nm, preferably less than 50 nm, and particularly preferably less than 10 nm, for example, within 2 nm. This allows the utilized radiation energy to be selectively limited to the required range, thereby minimizing or even completely preventing energy losses. In a preferred embodiment, the radiation source is suitable for emitting IR radiation in an IR wavelength range from 1.4 pm to 3.3 pm, particularly preferably in a range from 1.45 pm to 1.95 pm or a range from 2.6 pm to 3.1 pm. It is not necessary for the emission band of the radiation source to completely cover the aforementioned ranges. However, the emission band should lie (at least partially) within these ranges.The radiation source preferably emits in an IR wavelength range of one or more of the absorption maxima of water. The radiation source is advantageously connected to a power supply unit.

[0027] In the preferred wavelength range of 2.6 pm to 3.1 pm, the absorption and excitation of water molecules, and thus the resulting heating and evaporation, are particularly high. Advantageously, it has been shown that the transmission of glass in the wavelength range of 2.9 pm to 3.1 pm is particularly high at over 70%, and especially at approximately 3.0 pm at approximately 85%, so that the energy can be used efficiently for de-icing and evaporating water.

[0028] In the alternative preferred region, the radiation source is suitable for emitting IR radiation in the IR wavelength range from 1.45 pm to 1.95 pm. In this range, the radiation is particularly energy-intensive and therefore very suitable for evaporating water.

[0029] The radiation source preferably comprises a halogen lamp with a bandpass filter, an LED, an OLED, and / or a laser diode, preferably an LED. In particular, the radiation source comprises an LED, which can also be referred to as an "IR-emitting diode." Alternatively, the radiation source can comprise laser diodes or lasers, which have the advantage of being particularly powerful and efficient. In addition to the aforementioned elements for generating IR radiation, the radiation source can also include other elements, such as a housing in which the IR-generating elements are mounted. Alternatively, the radiation source can be an LED, an OLED, and / or a laser diode.

[0030] In an exemplary embodiment of the invention, the radiation source comprises or consists of an Er:YAG diode. The Er:YAG diode has a wavelength of approximately 2960 nm. Another example of a radiation source is a narrowband Cr:ZnSe / S CW laser emitter that can emit dimmable wavelengths in the range between 1.9 and 3.0 pm. In this case, a lens, for example a concave lens, can also be used to reduce the intensity and can additionally change the direction of the laser beams. Other examples are InAs / GaSb, Er 3+-doped sesquioxide diodes. For example, an InGaAsP diode with a wavelength of 1900 nm can also be used. The wavelength ranges mentioned correspond to frequency and wavelength ranges in which water molecules exhibit the highest absorption coefficient for IR radiation. At the same time, the transmission of glass in this IR radiation range is particularly high (TL > 80%), and only a small portion of the IR radiation is absorbed.

[0031] The radiation sources can be, for example, ribbon-shaped or spot-shaped. Other geometric shapes are also possible. Several individual radiation sources can be arranged side by side, spaced apart, or in a ribbon-like arrangement (close together). In other words, if several spot-shaped LEDs are arranged next to each other, a multi-part, ribbon-shaped radiation source can be created. This allows the number and intensity of the radiation sources to be flexibly adapted to the requirements for heating the respective sensor penetration area of ​​the laminated glass, for example, with regard to the spatial and geometric conditions and the energy required for efficient heating.

[0032] In a preferred embodiment of the vehicle windscreen arrangement according to the invention, when using an IR-based sensor, in particular a lidar sensor, the IR heating radiation is selected such that there is a wavelength difference of at least 300 nm, in particular at least 400 nm, between the sensor radiation and the heating radiation. This advantageously prevents impairment or interference of the sensor signals by the IR heating radiation.

[0033] In a preferred embodiment, the first and second panes, preferably each a single glass pane, are made of soda-lime glass, which is common for vehicle windows, for example, in the form of safety glass. However, the panes can also be made of other types of glass (for example, borosilicate glass, quartz glass, aluminosilicate glass). Alternatively, the pane can also be made of plastic, i.e., transparent polymers, for example, polycarbonate. The thickness of the pane can vary widely. Panes with a thickness in the range of 0.5 mm to 10 mm are preferred, more preferably from 1 mm to 5 mm, and most preferably from 3.15 mm to 4.85 mm.

[0034] In a preferred embodiment, the thermoplastic interlayer is preferably transparent, tinted, or colored. The interlayer preferably contains or consists of at least one plastic, preferably polyvinyl butyral (PVB), ethylene vinyl acetate (EVA), and / or polyethylene terephthalate (PET). However, the interlayer can also contain, for example, polyurethane (PU), polypropylene (PP), polyacrylate, polyethylene (PE), polycarbonate (PC), polymethyl methacrylate, polyvinyl chloride, polyacetate resin, casting resins, acrylates, fluorinated ethylene propylenes, polyvinyl fluoride, and / or ethylene tetrafluoroethylene, or copolymers or mixtures thereof. The interlayer can be formed by one or more films arranged one above the other, the thickness of each film preferably being from 0.025 mm to 1 mm, typically 0.38 mm or 0.76 mm.The intermediate layer is thermoplastic and, after lamination, bonds the first pane, the second pane, and any further intermediate layers together.

[0035] In a preferred embodiment, the radiation source can be functionally connected to at least one sensor, in particular a temperature and / or humidity sensor. This can advantageously be used for automated defrosting or removal of condensed moisture. Additionally, it can prevent icing of the laminated glass or the formation of condensation and the associated obstruction of vision. Such a sensor is preferably mounted on the laminated glass. The heating device can be functionally connected to a control unit, in particular on-board electronics, and / or to one or more environmental sensors, and these can communicate with each other.The environmental sensor(s) can include, in particular, one or more rain sensors, temperature sensors, humidity sensors, conductivity sensors, and / or various other sensors designed to detect ambient conditions and the state of the vehicle windows in relation to the removal of condensation (defogging) and / or frost from the vehicle windows. During operation, the control unit can monitor the status of the environmental sensors and, for example, automatically activate the heating system to remove ice or condensation from the vehicle windows and / or prevent frost and / or moisture from accumulating on them.During operation or vehicle start-up, a control unit, in functional conjunction with the sensors, can identify whether moisture is detected by the humidity sensor and / or whether the temperature sensor registers a temperature below a freezing threshold. Accordingly, based on the detected humidity level and / or the specified temperature, the control unit can determine whether conditions exist to automatically activate the heating system to heat one or more of the vehicle windows and remove condensation. Manual activation of the heating system can also be provided as an alternative or additional option.

[0036] The at least one radiation source can be arranged such that it couples IR radiation into the entire composite disk, i.e., all layers of the composite disk. Preferably, the at least one radiation source is arranged relative to the composite disk such that it couples IR radiation into the first disk, the second disk, or into an optical waveguide arranged between the first and second disks. The at least one output coupling element is in contact with the disk or the optical waveguide in such a way that the coupled IR radiation can be extracted via the output coupling element. In other words, if the at least one radiation source couples IR radiation into the first disk, then the at least one output coupling element is in direct contact with the first disk in the transmission area or is a component of the first disk as a structural element of the disk.

[0037] In a further preferred embodiment of the invention, the at least one radiation source is arranged on at least one section of a circumferential edge surface of the composite disk, i.e. on at least one edge surface of the composite disk, preferably on at least one edge surface of the first disk or the second disk, which accordingly comprises the entry area for the IR radiation.

[0038] The at least one radiation source can, for example, be assigned section by section to at least one side edge surface and / or be attached to the top and / or bottom edge, for example, by being glued on or arranged in a holder attached to the laminated glass, or it can completely occupy an edge surface. The IR radiation can then be coupled into the laminated glass, for example, via one, two, or three edge surface sections. It can be advantageous to irradiate the glass from one or more sides with several radiation sources in order to increase the heating effect accordingly. A particular advantage of the present invention is that the heating effect is increased by the provided coupling element, and compared to an embodiment without this measure, fewer radiation sources and less energy are required for the same heating effect.

[0039] In one embodiment of the vehicle windscreen arrangement according to the invention, the radiation source(s) is distributed at the upper edge of the laminated windscreen, for example, substantially adjacent to the sensor or arranged directly adjacent to each other. In a further embodiment, the at least one sensor and the at least one radiation source are arranged in a common housing.

[0040] In a further embodiment of the invention, the at least one radiation source is arranged in a recess of the composite disk, preferably in a recess of the first or the second disk. The radiation source is arranged in the recess such that it can couple IR radiation into the optical waveguide, which can then be used either for removing condensed moisture or for de-icing. The recess in the first or second disk is, for example, a hole, i.e., a through-hole, which extends continuously between the first and second surfaces of the disk. Alternatively, the recess can also be a depression similar to a blind hole (sack-like depression), which extends from the second surface or the first surface into the disk without reaching the opposite main surface, thus creating a through-hole.The recess can be created, for example, by mechanical drilling or laser processing. The recess is preferably round, but can, in principle, have any shape, including a polygonal shape. This refers to the base of the recess in the plane of the at least one surface of the optical fiber through which the recess is inserted. The recess has the overall shape of a cylinder, preferably a vertical cylinder. The cylinder is preferably a circular cylinder (circular base), but can also have any other base shape, for example, an elliptical base (elliptical cylinder) or a polygonal base (prism).

[0041] The recess, whether a through-hole or a depression, is bounded by a circumferential edge surface that extends between the main surfaces of the first or second disk. In the case of a through-hole, this is the only boundary surface of the recess. In the case of a sac-like depression, there is a further boundary surface that faces the main surface of the first or second disk to which the depression does not extend, and which effectively forms the bottom of the sac-like cavity.

[0042] The radiation source is arranged on the edge surface of the recess in the first or second disk, preferably attached, in particular glued, or arranged in a socket mounted on / in the recess. The IR radiation is then coupled into the disk, which acts as an optical waveguide, via the inner edge surface and selectively coupled out by the output element in sensor penetration areas covered with water, for example at existing icing or at points with condensed moisture from the interior of the optical waveguide.

[0043] Mixtures and combinations of the aforementioned configurations are also possible. Likewise, a radiation source can be arranged in a recess of the first or second disk, and an additional radiation source can be attached to an edge of the disk. These are only exemplary configurations and are not exhaustive.

[0044] A preferred embodiment provides that the radiation source is functionally connected to at least one control unit and / or on-board electronics. The radiation source can be controlled, in particular, by means of the control unit and / or the on-board electronics. Preferably, the control unit or the on-board electronics also serve as a voltage source for the radiation source.

[0045] In a preferred embodiment, an IR mirror layer is applied to a surface of the composite disk and the radiation source is arranged to the IR mirror layer in such a way that the emitted IR radiation can be coupled into the composite disk by means of reflection at the IR mirror layer.

[0046] In one embodiment, the radiation source is applied to a surface, for example, the second surface of the inner-facing second pane, while the first surface of the second pane has an IR mirror layer, i.e., a reflective coating for the infrared range, which is arranged to overlap the at least one radiation source when viewed through the laminated pane. In this way, the optical fiber is irradiated with IR radiation via the second surface. The at least one radiation source is attached to the second surface of the optical fiber, for example, by bonding it with an optically clear adhesive (OCA). This couples the IR radiation into the optical fiber via reflection from the IR mirror layer. Alternatively, an additional optical fiber can be routed outwards from the edge of the pane, so that the IR heating radiation is coupled directly into this additional optical fiber.This reduces the complexity of the vehicle windscreen arrangement, as the radiation source does not need to be positioned on the edge surfaces of the windscreen acting as an optical fiber. Alternatively, the IR reflective layer can also be applied to the first surface of the optical fiber. In this case, the radiation source is then applied to the second surface. When viewed through the laminated windscreen, the IR reflective layer and the radiation source overlap, essentially forming a single, overlapping layer.

[0047] An optically clear adhesive is preferably a material containing or made from polyacrylate compounds (e.g., polyacrylate or polymethyl acrylate) or silicone. For the purposes of this invention, "clear" means that the adhesive is transparent.

[0048] Furthermore, the vehicle windscreen arrangement of the present invention comprises a coupling element for the IR heating radiation, which is preferably arranged in the intermediate layer. The IR radiation source is preferably arranged adjacent to the coupling element, so that the light from the radiation source, after propagation from the point of coupling in the transmission area of ​​the sensor radiation, can be coupled at least partially into the water molecules of the condensation via the coupling element. The coupling element is designed to deflect at least a portion of the IR light arriving from the IR radiation source by scattering, diffraction, refraction, or, in particular, by reflection, and to couple it out of the laminated windscreen.

[0049] For this purpose, a microprism film, or more preferably a microstructured polymer film, can preferably be used, which is arranged between the first and second disks at least in the transmission area of ​​the sensor beams. According to the invention, the output coupling element can be multilayered, consisting of a carrier layer and a microprism film.

[0050] The carrier layer can consist of a thermoplastic polymer material. Materials used for the carrier layer are particularly preferred if they are also used for the intermediate layer. The carrier layer therefore preferably also contains or consists of at least one plastic, preferably polyvinyl butyral (PVB), ethylene vinyl acetate (EVA), and / or polyethylene terephthalate (PET). However, the carrier layer can also contain, for example, polyurethane (PU), polypropylene (PP), polyacrylate, polyethylene (PE), polycarbonate (PC), polymethyl methacrylate, polyvinyl chloride, polyacetate resin, casting resins, acrylates, fluorinated ethylene propylenes, polyvinyl fluoride, and / or ethylene tetrafluoroethylene, or copolymers or mixtures thereof. The carrier layer can be formed by one or more films arranged one above the other, the thickness of each film preferably being from 0.025 mm to 1 mm, typically 0.38 mm or 0.76 mm.The carrier layer is preferably bonded, laminated, or otherwise firmly connected to the microprism film to form the extraction element. The microprism film itself is known, in particular, from traffic engineering as a reflective film, from lighting technology, or from display technology, for example, as a Brightness Enhancement Film (BEF). This can be, in particular, a film comprising a base layer and a microprism layer arranged on the base layer. In this case, the base layer of the microprism film is thus present in addition to the carrier layer of the extraction element, as required by the present invention. In other words, the carrier layer, the base layer, and the microprism layer are all included in the extraction element.

[0051] In a preferred embodiment of the invention, the decoupling element is arranged in a section of the intermediate layer or - in the case of a small height - on the intermediate layer, depending on its own height.

[0052] When an IR mirror layer is used for coupling, the IR radiation from the radiation source is reflected (at least partially) back towards the IR-conducting element, preferably the second disk, by the IR mirror layer. There, the IR radiation is coupled into the IR-conducting element by utilizing the principle of total internal reflection. This helps to distribute the IR radiation within the IR-conducting element and direct it to areas to be heated, i.e., icy or condensation-covered areas of the composite disk. The "IR-conducting element" is preferably the second disk or an optical waveguide arranged between the first and second disks. Alternatively, the IR-conducting element can also be the first disk.

[0053] An IR mirror layer for coupling in the IR radiation, hereinafter also referred to as a coupling mirror layer, can be arranged in the form of a coated thermoplastic film, for example made of polyethylene terephthalate (PET), on the IR-radiation-conducting element, preferably the second disk. In this embodiment, the radiation source(s) is / are preferably arranged in an area of ​​the IR-radiation-conducting element that, in its installed position, cannot be seen from the vehicle interior or the external environment (for example, concealed by seals or other vehicle components). The IR coupling mirror layer is preferably a prismatic film, which may additionally be coated with an IR-reflective coating based on an electrically conductive oxide. In particular, the IR coupling mirror layer is a microprism film, which may additionally be coated with an IR-reflective coating based on an electrically conductive oxide.The inclined surfaces of the prism foil cause the IR rays to be reflected at a particularly advantageous angle at the IR mirror layer, so that they strike the IR radiation-guiding element at an angle of incidence at which a particularly high proportion of the IR radiation can be coupled in.

[0054] In a further embodiment of the invention, the radiation source is applied to the first or second surface of the IR-conducting element, preferably the second surface of the second disk, by means of an optically clear adhesive formed in the shape of an oblique wedge. Preferably, the radiation source is applied in the edge region of the IR-conducting element. For the purposes of the invention, "oblique wedge" refers to a wedge shape comprising two triangular side faces, two rectangular base faces, and a base surface. The triangular side faces are not perpendicular, so the two base surfaces are of different sizes. The base surface is the smallest of the surfaces of the oblique wedge and is arranged at an angle greater than 90° to one of the base surfaces and at an angle less than 90° to the other base surface.In this embodiment, the optically clear adhesive is applied to the IR-conducting element such that its base surface is at an angle of less than 90° to the base of the wedge, which is in contact with the surface of the optical waveguide. The radiation source is arranged such that the IR radiation first transmits through the optically clear adhesive before penetrating the element, whereby the IR radiation is at least partially coupled into the IR-conducting element by utilizing the effect of total internal reflection. The radiation source is positioned so that, during operation, it irradiates the base surface of the optically clear adhesive, with the emitted IR radiation preferably striking the adhesive perpendicular to the base surface.The base surface of the optically clear adhesive preferably has an angle to the surface of the optical waveguide that is suitable for coupling IR radiation into the IR-conducting element. The optically clear adhesive preferably has a refractive index that differs from the refractive index of the IR-conducting element by less than 0.1, preferably less than 0.05. This results in minimal or significantly less refraction of the IR radiation at the interface between the optically clear adhesive and the IR-conducting element. Nevertheless, any existing refraction between the optically clear adhesive and the IR-conducting element can be taken into account when selecting the angle of the base surface to the surface of the IR-conducting element.In a further embodiment of the invention, the composite disc comprises at least one further radiation source, preferably at least two further radiation sources, which are suitably arranged to couple IR radiation into the composite disc. The radiation sources are preferably switchable and operable independently of one another. Thus, the associated radiation sources can be controlled independently of one another, so that the heating power or intensity can be selectively adjusted.

[0055] In a preferred embodiment, the at least one radiation source is arranged in an opaque area, preferably an edge area, for example coated with a conventional masking print, of the composite pane, which completely covers the radiation source in the direction of transmission through the composite pane. This allows the radiation sources to be optically concealed from the outside.

[0056] The invention further extends to a vehicle or vehicle components comprising at least one selectively heated vehicle windshield assembly as described above in various embodiments.

[0057] The invention further extends to a method for manufacturing a vehicle disc assembly as described above in various embodiments, comprising at least the following steps:

[0058] (A) the radiation source is arranged to be connected to the composite disk in such a way that the IR radiation is coupled into the disk, and

[0059] (B) In at least one passage area of ​​a sensor, a coupling element is arranged for the selective coupling out of the IR radiation.

[0060] Furthermore, the invention extends to the use of the vehicle window arrangement in vehicles for traffic on land, in the air or on water, in particular as a selectively heated side window, rear window, roof window or windshield in motor vehicles, especially in electric vehicles.

[0061] The various embodiments of the invention can be implemented individually or in any combination. In particular, the features mentioned above and to be explained below can be used not only in the combinations specified, but also in other combinations or on their own, unless they are explicitly described as possible only as alternatives to one another without departing from the scope of the present invention.

[0062] The invention is explained in more detail below with reference to exemplary embodiments, with reference to the accompanying figures. These show, in a simplified representation not to scale:

[0063] Fig. 1 shows a vehicle disc arrangement according to the invention in a purely schematic cross-sectional view,

[0064] Fig. 2 shows a further embodiment of an invention

[0065] Vehicle window arrangement in a highly schematic cross-sectional view,

[0066] Fig. 3 shows a further embodiment of an invention

[0067] Vehicle window arrangement in a highly schematic cross-sectional view and

[0068] Fig. 4 shows an absorption spectrum of water (liquid state).

[0069] Figure 1 shows a first embodiment of a vehicle windscreen assembly 100 according to the invention as a windscreen of a passenger car in a schematic cross-sectional view. The vehicle windscreen assembly comprises at least one laminated glass pane 1 with an outer first pane 2, an inner second pane 3, and at least one thermoplastic intermediate layer 4 arranged between the first and second panes 2, 3. For the sake of simplicity, the laminated glass pane 1 of the assembly 100 is shown in plan view, although vehicle windscreens are typically curved in reality. The first pane 2 and the second pane 3 are preferably made of soda-lime glass, but can also be made of other types of glass (for example, borosilicate glass, quartz glass, aluminosilicate glass). The thickness of the first pane 2 and the second pane 3 can vary widely.Preferably, discs 2, 3 with a thickness in the range of 0.5 mm to 10 mm, preferably from 1 mm to 5 mm, are used.

[0070] The thermoplastic interlayer 4 is, for example, made of PVB. The interlayer 4 is, for example, formed from a thermoplastic film. The thickness of the film is, for example, 0.76 mm. However, the interlayer 4 can also comprise several layers of thermoplastic material and, for example, be formed from several polymer films arranged one above the other in a planar arrangement. The vehicle window arrangement 100 according to the invention also comprises at least one interior-side optical sensor 5, which emits and / or receives rays in a penetration area 6 through the laminated window 1 to acquire information about the conditions of the outside environment, wherein the penetration area 6 forms only a partial area of ​​the laminated window 1. The optical sensor 5 is, for example, a camera.

[0071] An IR radiation source 7, for example an LED with a wavelength in the range of 1.3 pm to 3.5 pm, is arranged in the region of the upper edge of the composite disk 1. The upper edge thus forms an entry point for the IR radiation 8. In this embodiment, the second disk 3 is the IR-conducting element. The radiation source 7 can, for example, be one or more Er:YAG diodes that have or can emit a wavelength of approximately 2960 nm. Another example of a radiation source 7 is a narrowband Cr:ZnSe / S CW laser emitter that can emit dimmable wavelengths in the range between 1.9 and 3.0 pm. In this case, a lens, for example a concave lens, can also be used to reduce the intensity and can also change the direction of the laser beams.This wavelength corresponds to the frequency and wavelength range in which water molecules exhibit the highest absorption coefficient for IR radiation. The slight absorption of the IR radiation 8, which might lead to a slight warming of the composite disc 1, then contributes to removing the coating from it as well. The radiation source 7 is, for example, attached to the upper edge of the second disc 3. In this configuration, the radiation source 7 is designed and / or arranged in a ribbon-like form. Furthermore, the radiation source 7 is functionally connected, for example, to a control and / or regulating unit (not shown here). The arrow indicates, by way of example and schematically, the direction of radiation of the IR radiation 8. The IR radiation 8 is coupled into the second disc 3 via the upper edge.

[0072] In areas where an aqueous coating (moisture) has formed on the composite disc 1, i.e., where the composite disc 1 is covered with water droplets or ice crystals, for example, the IR radiation 8 is selectively coupled out in the transmission area 6. This is because, independent of passive coupling, active coupling occurs via the coupling element 9 due to the different refractive index of water compared to air. The IR radiation 8 is absorbed by the water molecules, which are heated by the excitation of the radiation 8 and thus evaporate. A particular advantage of the invention is that IR radiation 8 can be used with the wavelength and frequency range in which water molecules exhibit the highest absorption coefficients, thus achieving a very selective heating effect. This contributes to achieving a particularly energy-efficient heating effect.Active extraction via the extraction element 9 can make a further significant contribution to this.

[0073] Energy efficiency is an extremely important criterion for future product development. Advantageously, according to the invention, the heating effect does not depend on the heating of the composite pane 1 itself, but is achieved selectively by exciting the water molecules through the IR radiation 8 only in the sensor beam transmission area. The heating effect therefore occurs much faster than with previously used heating devices, and there is also no heat loss due to convection and the large surface area of ​​the composite pane 1. Thus, the dependence of the effect on the outside temperature is also significantly lower than with previously known heating devices, which first have to heat the composite pane 1 to ultimately remove condensate and ice.

[0074] The extraction element 9 is arranged on the surface of the second disk 3 facing the intermediate layer 6 in the transmission area 6. The IR radiation source 7 is preferably arranged adjacent to the extraction element 4, so that the light from the radiation source, after propagation in the transmission area 6, can be at least partially coupled into the water molecules of the condensation via the extraction element 9. The extraction can be directed outwards on one side, but preferably both outwards and inwards. This is shown in Figure 1 as a gray-shaded area. In the case of extraction on both sides, for example, a double-sided microprism film or a microlens array is used as the extraction element 9.The extraction element 9 is designed to deflect at least a portion of the IR light 8 arriving from the IR radiation source 7 by scattering, diffraction, refraction, or, in particular, by reflection, and to extract it from the composite disk 1. Alternatively, depending on its own height, the extraction element 9 can be arranged, for example, in a recess of the intermediate layer 4 or – in the case of a small height – on the intermediate layer 4.

[0075] Figure 2 shows a further embodiment of the vehicle window assembly 100 according to the invention in a highly schematic cross-sectional view. The basic structure of the vehicle window assembly 100, comprising a composite window 1, a sensor 5, a penetration area 6 through the composite window 1, and a coupling element 9, is identical to the embodiment described in Figure 1. In the embodiment shown here, the composite window 1 additionally includes an optical fiber 10, which is arranged between the first window 2 and the second window 3. The optical fiber 10 is suitable for propagating the IR heating radiation 8 from the narrowband IR radiation source 7 into the window 1 without loss. The additional optical fiber 7 extends beyond the edge of the composite window 1. In this way, it is possible to arrange the IR radiation source 7 outside the composite window 1, so that the coupling area for the IR heating radiation 8 is also located outside the composite window 1.This allows for greater flexibility in the placement of the IR radiation source 7. It is also possible, in the embodiment shown here, to arrange the IR radiation source 7 together with the sensor 5 in a common housing. The extraction of the IR heating radiation 8 occurs selectively in the transmission area 6 of the sensor beams, thus achieving highly efficient removal of ice or water condensation.

[0076] Figure 3 shows a further embodiment of the vehicle window arrangement 100 according to the invention in a highly schematic cross-sectional view. The basic structure of the vehicle window arrangement 100 with laminated window 1, sensor 5, passage area 6 through the laminated window 1, and coupling element 9 is identical to the embodiment described for Figure 1. In this embodiment, the radiation source 7 is arranged on the surface of the second window 3 facing away from the intermediate layer 4. The IR radiation 8 from the radiation source 7 is coupled into the second window 3, for example, by means of an IR mirror layer (not shown here). The IR mirror layer is, for example, a reflective microprismatic film that is applied to the surface of the second window 3 facing the intermediate layer 4, opposite the radiation source 7.

[0077] Figure 4 shows an absorption spectrum of water in the liquid state. The diagram shows that water molecules, for example, exhibit a particularly high absorption coefficient at a wavelength of approximately 3 pm. In a preferred embodiment, a radiation source in the IR wavelength range of 2.5 pm to 3.3 pm, and particularly preferably from 2.9 pm to 3.1 pm, is therefore used for the heated vehicle windshield assembly, since the absorption and excitation of the water molecules, and thus the resulting heating and evaporation, are particularly high in this preferred wavelength range. Preferably, the IR-conducting element simultaneously exhibits a transmission in the wavelength range of 2.9 pm to 3.1 pm of over 70%, and particularly at approximately 3.0 pm of approximately 85%, so that the radiation energy can be used efficiently for defrosting and evaporating water in the corresponding ranges. (Reference numeral list)

[0078] 1 composite disc

[0079] 2 outer first pane 3 inner second pane

[0080] 4 thermoplastic intermediate layer

[0081] 5 Sensor

[0082] 6. Passage area of ​​the sensor beams

[0083] 7 IR radiation source 8 IR radiation

[0084] 9 Coupling element

[0085] 10 optical fibers / IR radiation conducting element

[0086] 100 vehicle disc arrangement

Claims

Patent claims 1. Vehicle window assembly (100) comprising at least one laminated glass pane (1) with an outer first pane (2), an inner second pane (3) and at least one thermoplastic intermediate layer (4) arranged between the first and second panes (2, 3), at least one inner-side sensor (5) which emits and / or receives radiation through the laminated glass pane (1) in a transmission area (6) to detect information about the conditions of the outside environment, wherein the transmission area (6) forms only a partial area of ​​the laminated glass pane (1), and at least one narrowband radiation source (7) for radiation (8) in the IR wavelength range from 1.3 pm to 3.5 pm for removing water-based condensation from the transmission area (6), wherein the radiation source (7) is arranged to be connected to the laminated glass pane (1) in such a way thatthat the IR radiation (8) emitted by the radiation source (7) is coupled into the composite disk (1) in an entry region, characterized in that at least one output coupling element (9) for the IR radiation (8) of the radiation source (7) is arranged in the passage region (6).

2. Vehicle window arrangement (100) according to claim 1, wherein the sensor (5) is a camera or an IR sensor, and in particular a lidar sensor.

3. Vehicle window arrangement (100) according to claim 1 or 2, wherein the narrowband IR radiation source (7) is a halogen lamp with band filter, an LED, an OLED or a laser diode, preferably an LED.

4. Vehicle window arrangement (100) according to one of claims 1 to 3, wherein the radiation source (7) can emit IR radiation (8) in an IR wavelength range from 1.4 pm to 3.3 pm, preferably in a range from 1.45 pm to 1.95 pm or from 2.6 pm to 3.1 pm, and particularly preferably in an IR wavelength range of one or more of the absorption maxima of water.

5. Vehicle windscreen arrangement (100) according to one of claims 1 to 4, wherein, when using an IR sensor radiation-based sensor (5), in particular a lidar sensor, the IR radiation (8) of the radiation source (7) is selected such that a A wavelength difference of at least 300 nm, in particular at least 400 nm, exists between the sensor radiation and the IR radiation (8) of the radiation source (7).

6. Vehicle windscreen arrangement (100) according to one of claims 1 to 5, wherein the at least one sensor (5) and the at least one radiation source (7) are arranged in a common housing.

7. Vehicle window arrangement (100) according to one of claims 1 to 6, wherein the radiation source (7) is arranged on at least one section of a circumferential edge surface of the composite window (1).

8. Vehicle window arrangement (100) according to one of claims 1 to 6, wherein the radiation source (7) is arranged in a recess of the composite window (1).

9. Vehicle window arrangement (100) according to one of claims 1 to 8, wherein an IR mirror layer, preferably in the form of a prism film, is applied to a surface of the composite window (1) and wherein the radiation source (7) is arranged to the IR mirror layer such that the emitted IR radiation (8) can be coupled into the composite window (1) by means of reflection at the IR mirror layer.

10. Vehicle window arrangement according to one of claims 1 to 9, wherein the decoupling element (9) is a prismatic film, preferably a microstructured polymer film.

11. Method for manufacturing a vehicle window assembly (100) according to any one of claims 1 to 10, wherein (A) the radiation source (7) is arranged to be connected to the composite disk (1) in such a way that the IR radiation (8) is coupled into the composite disk (1), and (B) in at least one passage area of ​​a sensor (5) an output coupling element (9) for selectively coupling out the IR radiation (8) is arranged.

12. Use of the vehicle window arrangement (100) according to one of claims 1 to 10 in vehicles for traffic on land, in the air or on water, in particular as a selectively heated side window, rear window, roof window or windshield in motor vehicles, especially in electric vehicles.

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