WO2024068174A1

WO2024068174A1 - Assembly for a driver assistance system, comprising a heatable vehicle glazing

Info

Publication number: WO2024068174A1
Application number: PCT/EP2023/073804
Authority: WO
Inventors: Markus KEWITZ; Julian GREVERATH; Sebastian ARENDT; Michele CAPPUCCILLI
Original assignee: Saint-Gobain Glass France
Priority date: 2022-09-26
Filing date: 2023-08-30
Publication date: 2024-04-04

Abstract

The invention relates to an assembly (1) for a driver assistance system (100) of a vehicle (2). The vehicle glazing (5) has at least one functional layer (12) which reflects infrared radiation and a reflective region (22), wherein the functional layer (12) is designed to be electrically conductive and is provided as a heating device for heating the vehicle glazing (5). At least two busbars (20, 21) are provided for electrically contacting the functional layer (12), and a heating zone (H) is formed between the at least two busbars (20, 21) when an electric voltage is applied to the two busbars (20, 21). The reflective region (22) is arranged between the at least two busbars (20, 21), and the length of one busbar (20, 21) corresponds to the length of a lateral edge of the reflective region (22).

Description

Arrangement for driver assistance system with heated vehicle glazing

The invention relates to an arrangement with vehicle glazing, a radiation source for emitting infrared radiation and a radiation receiver for receiving infrared radiation for a driver assistance system of a vehicle, which enables infrared-based monitoring of the driver. The invention further relates to a driver assistance system of a vehicle with such an arrangement, as well as a method for monitoring the driver of a vehicle.

Modern vehicles are often equipped with electronic driver assistance systems that support the driver in driving the vehicle, for example by automatically applying the brakes when there is a risk of a collision or automatically keeping the vehicle in lane when it leaves its lane. Such driver assistance systems have proven to be very effective in practice, particularly when they have a monitoring function for the driver, for example to detect driver fatigue at an early stage, but also to detect excessive distraction from safe driving, for example by using a mobile phone.

For this purpose, it is known to scan the driver's face and in particular his eyes using infrared radiation, which is not visible to the naked eye and therefore does not disturb the driver and the other vehicle occupants. Sophisticated algorithms can be used to record the direction and duration of the driver's gaze, which can indicate tiredness, for example, if the gaze in a certain direction is unusually long (staring). On the other hand, looking away from the direction of travel too often can indicate distraction. It is also possible to recognize facial expressions, which can also provide an indication of the driver's condition.

DE 10 2006 019 112 A1 discloses a vehicle with a windshield that has an area that reflects infrared light coming from the vehicle interior and transmits visible light. An infrared source camera is arranged in the vehicle and is directed at the area of the windshield reflecting infrared light.

WO 2022/157022 A1 discloses a pane with a heatable sensor field, which comprises a heatable film attached to the sensor field. The film consists of a coated carrier film, whereby the coating is electrically conductive. The film is firmly bonded to the pane via an adhesive layer.

The invention is based on the object of providing an improved arrangement with a vehicle glazing, a radiation source and a radiation receiver for a driver assistance system with infrared-based monitoring function, which enables reliable acquisition of information about the vehicle user at low temperatures and humid weather.

This object is achieved according to the invention by an arrangement with vehicle glazing, in particular a windshield, a radiation source and a radiation receiver for infrared radiation for a driver assistance system according to the independent patent claim. Preferred embodiments emerge from the subclaims.

An arrangement according to the invention for a driver assistance system for a vehicle, in particular a motor vehicle, with a monitoring function of a vehicle user, in particular a driver of the vehicle, is based on the use of infrared radiation. The arrangement includes a radiation source for emitting infrared radiation and a radiation receiver for receiving infrared radiation. The arrangement further comprises a composite pane, which serves as vehicle glazing, and consists of an outer pane and an inner pane, which are connected to one another in terms of area via a thermoplastic intermediate layer. The vehicle glazing, in particular as a windshield, serves to separate an interior from an external environment in the vehicle. The inner pane refers to the pane that faces the interior when installed. The outer pane refers to the pane that faces the outside environment in the installed position. The surfaces or sides of the two individual panes are usually referred to as side I, side II, side III and side IV from the outside to the inside.

It is essential that the vehicle glazing has at least one functional layer that is suitable for reflecting infrared radiation. The vehicle glazing also has a reflection area. The infrared radiation is preferably only reflected by the reflection area of the vehicle glazing. The functional layer is designed to be electrically conductive and is intended as a heating device for heating the vehicle glazing. With the invention, the driver assistance system can work trouble-free in poor weather or visibility conditions, since fogging and icing on the inner window can be removed quickly and easily. The Reflection area of vehicle glazing can reflect radiation clearly and distinctly. This radiation is detected by a radiation receiver. Information about the facial condition of a vehicle user (driver) can be obtained from the recorded data.

In the arrangement according to the invention, at least two current collectors are provided for electrically contacting the functional layer, with a heating zone being formed between the at least two current collectors. The current collectors can be strip-shaped and arranged on the functional layer in an electrically conductive manner. The current collectors typically run along the upper and lower edges of the pane. In such an arrangement, the heating current flows essentially evenly through the functional layer, which is thus heated evenly in the reflection area. Advantageously, even in poor weather conditions (fogging and icing), the vehicle glazing can be quickly freed of moisture and infrared radiation can be reflected without interference in an energy-efficient manner. In addition, by heating the reflection area or vehicle glazing via the electrically conductive functional layer, the typically used heating variant using the air conditioning system (HVAC) method is superfluous when installing the vehicle glazing in a vehicle.

In an advantageous embodiment of the invention, the at least two current collectors can be applied to the surface of the first inner pane and/or to the electrically conductive functional layer by means of soldering or gluing. The current collectors applied in this way are preferably designed as a wire or strip of an electrically conductive film. The current collectors then contain, for example, at least aluminum, copper, tinned copper, gold, silver, zinc, tungsten and/or tin or alloys thereof. The strip preferably has a thickness of 10 pm to 500 pm, particularly preferably 30 pm to 300 pm. Current collectors made of electrically conductive films with these thicknesses are technically simple to produce and have an advantageous current-carrying capacity. The strip can be electrically connected to the electrically conductive structure, for example, via a solder compound, via an electrically conductive adhesive or by direct application.

Alternatively, the at least two current bus conductors are designed as a printed and burned-in conductive structure. The printed current bus conductors then preferably contain at least one metal, a metal alloy, a metal compound and/or carbon, particularly preferably a noble metal and in particular silver. The printing paste preferably contains metallic particles, metal particles and/or carbon and in particular precious metal particles such as Silver particles. The electrical conductivity is preferably achieved by the electrically conductive particles. The particles can be in an organic and/or inorganic matrix such as pastes or inks, preferably as printing paste with glass frits.

The layer thickness of the printed current bus conductor is preferably from 5 pm to 40 pm, particularly preferably from 8 pm to 20 pm and very particularly preferably from 8 pm to 12 pm. Printed current bus conductors with these thicknesses are technically easy to implement and have an advantageous current-carrying capacity.

In a preferred embodiment, the at least two current collectors are each electrically contacted by one or more connecting lines. The connecting line is preferably designed as a flexible foil conductor (flat conductor, ribbon conductor). This is understood to mean an electrical conductor whose width is significantly greater than its thickness. Such a foil conductor is, for example, a strip or tape containing or consisting of copper, tinned copper, aluminum, silver, gold or alloys thereof.

In a further advantageous embodiment of the arrangement, one of the at least two current bus conductors extends over a length of less than 50%, preferably less than 40%, particularly preferably less than 30% of a side edge of the functional layer.

The reflection area of the vehicle glazing is preferably arranged within the heating zone. The area of the reflection area can be less than 50%, preferably less than 40%, particularly preferably less than 30% of the area of the heating zone. The reflection area can advantageously be arranged between the at least two current collectors. The length of a current collector can correspond to the length of a side edge of the reflection area. This allows the heating zone and thus the reflection area to be heated in a targeted manner. By heating the reflection area in a targeted manner, energy consumption can be significantly reduced compared to heating the entire surface of the vehicle glazing.

The radiation source is preferably arranged in such a way that infrared radiation emitted by the radiation source is directed onto the functional layer and can be reflected from the functional layer onto a driver's face. The infrared radiation emitted by the radiation source therefore hits the functional layer directly without prior reflection and is reflected by it. For ease of reference, the infrared radiation reflected by the functional layer is referred to as "first reflection radiation". The first reflection radiation hits on the driver's face and can be reflected back towards the functional layer. The first reflection radiation thus hits the driver's face directly without further reflection and is reflected by him. For ease of reference, the infrared radiation reflected from the driver's face is referred to as "second reflected radiation". The second reflection radiation striking the functional layer is then reflected by the functional layer. The second reflection radiation thus hits the functional layer directly without further reflection and is reflected by it. For ease of reference, the infrared radiation reflected by the functional layer is referred to as "third reflection radiation". Here, the radiation receiver is arranged in such a way that the third reflection radiation reflected by the functional layer is reflected to the radiation receiver and can be received by the radiation receiver.

The present invention is based on the knowledge that the functional layer with infrared radiation-reflecting properties, whose actual function is initially to heat the vehicle glazing, can also be used for the reflection of infrared radiation as part of the infrared-based monitoring function of the driver assistance system.

A particular advantage of the arrangement according to the invention is that the infrared radiation can hit the face from the front due to the reflection on the functional layer. The radiation reflected onto the driver's face can thus contain a portion of radiation that falls perpendicularly onto the driver's face. Likewise, the infrared radiation reflected in a corresponding manner from the face can be received, which contains a portion of radiation that is reflected perpendicularly from the driver's face.

Due to the indirect irradiation of the face, the radiation source and radiation receiver only have to be positioned on the functional layer with a view to a suitable reflection of the infrared radiation, which can usually be done in such a way that they are not or at least practically undetectable by the driver and front passenger, for example in the rear area of the console. This is another great advantage of the invention.

As described above, it is advantageous if the radiation source is arranged such that the first reflected radiation has a radiation component that strikes the driver's face perpendicularly. It can be advantageous here if the first reflection radiation is reflected from an area of the vehicle glazing that results at least partially from a horizontal projection of the driver's face onto the vehicle glazing. The first Reflection radiation can preferably hit the driver's face in a horizontal direction or along a vertical line. This enables very good recognition of details of the driver's face and, in particular, eye movements. Equally, it is advantageous if the radiation receiver is arranged in such a way that third reflection radiation reflected by the functional layer can be received, which is based on second reflection radiation which has a radiation component that was reflected perpendicularly from the driver's face. The third reflection radiation is advantageously reflected from an area of the vehicle glazing, which results at least partially from a horizontal projection of the driver's face onto the vehicle glazing. The second reflection radiation can then preferably hit the functional layer on the driver's face in a horizontal direction or along a vertical line. This also enables very good recognition of details of the driver's face and, in particular, eye movements.

The functional layer is arranged on a surface of the outer or inner pane and partially covers or covers the surface of the respective pane, but preferably over a large area. The term "large area" means that at least 50%, at least 60%, at least 70%, at least 75% or preferably at least 90% of the surface of the pane is covered (e.g. coated) by the functional layer. The functional layer can also extend over smaller portions of the surface of the pane, in particular only over that area of the vehicle glazing which serves to reflect infrared radiation (i.e. reflection area).

The functional layer is preferably transparent to visible light. In an advantageous embodiment, the functional layer is a single layer or a layer structure made up of several individual layers with a total thickness of less than or equal to 2 pm, particularly preferably less than or equal to 1 pm. In the context of the present invention, "transparent" means that the total transmission of the vehicle glazing as a windshield complies with the legal requirements and preferably has a transmittance of more than 70% and in particular more than 75% for visible light. Accordingly, "opaque" means a light transmission of less than 15%, preferably less than 5%, in particular 0%. The values for the light transmission (TL) and the reflection (RL) refer (as is usual for automotive glazing) to light type A, i.e. the visible portion of sunlight at a wavelength of 380 nm to 780 nm, i.e. essentially the visible spectrum of solar radiation. Infrared rays are understood to be rays with a wavelength of greater than about 800 nm. The electrically conductive functional layer typically contains one or more, for example two, three or four functional layers. The functional layers preferably contain at least one metal, for example silver, gold, copper, nickel and/or chromium or a metal alloy. The functional layers particularly preferably contain at least 90% by weight of the metal, in particular at least 99.9% by weight of the metal. The functional layers can consist of the metal or the metal alloy. The functional layers particularly preferably contain silver or a silver-containing alloy. Such functional layers have a particularly advantageous electrical conductivity with simultaneous high transmission in the visible spectral range. The thickness of a functional layer is preferably from 5 nm to 50 nm, particularly preferably from 8 nm to 25 nm. In this thickness range of the functional layer, an advantageously high transmission in the visible spectral range and a particularly advantageous electrical conductivity are achieved. The electrically conductive functional layer preferably extends over a range from 10 cm ² to 1000 cm ² , particularly preferably from 20 cm ² to 100 cm ² .

Typically, at least one dielectric layer is arranged between two adjacent functional layers of the coating. A further dielectric layer is preferably arranged below the first and/or above the last functional layer. A dielectric layer contains at least one individual layer made of a dielectric material, for example containing a nitride such as silicon nitride or an oxide such as aluminum oxide. However, dielectric layers can also include several individual layers, for example individual layers of a dielectric material, smoothing layers, adaptation layers, blocker layers and/or anti-reflection layers. The thickness of a dielectric layer is, for example, from 10 nm to 200 nm.

The electrically conductive functional layer can also contain or consist of indium tin oxide (ITO), fluorine-doped tin oxide (SnÜ2:F) or aluminum-doped zinc oxide (ZnO:Al). The functional layer can be a layer with a sun protection effect.

The thickness of the functional layer with a sun protection effect can vary widely and be adapted to the requirements of the individual case, with a layer thickness of 10 nm to 5 pm and in particular 30 nm to 1 pm being preferred. The surface resistance of the functional layer with a sun protection effect is preferably from 0.35 ohms/square to 200 ohms/square, preferably 0.5 ohms/square to 200 ohms/square, very particularly preferably from 0.6 ohms/square to 30 ohms/square, and particularly from 2 ohms/square to 20 ohms/square.

The functional layer or a carrier film with the functional layer can be arranged on a surface of one of the two panes of the vehicle glazing. For example, the functional layer is located on an inner surface of one or the other pane (i.e. side II or side III). For example, the functional layer is arranged on the inner surface of the inner pane (side III). Alternatively, the functional layer can be embedded between two thermoplastic intermediate layers. The functional layer is then preferably applied to a carrier film or carrier pane. The carrier film or carrier pane preferably contains a polymer, in particular polyvinyl butyral (PVB), ethylene vinyl acetate (EVA), polyurethane (PU), polyethylene terephthalate (PET) or combinations thereof.

The two panes of the vehicle glazing preferably contain or consist of glass, particularly preferably flat glass, float glass, quartz glass, borosilicate glass, soda-lime glass, or clear plastics, preferably rigid clear plastics, in particular polyethylene, polypropylene, polycarbonate, polymethyl methacrylate, polystyrene, polyamide, Polyester, polyvinyl chloride and/or mixtures thereof. Suitable glasses are known, for example, from EP 0 847 965 B1.

The thickness of the two panes can vary widely and be adapted to the requirements of the individual case. Preferably, panes with standard thicknesses of 1.0 mm to 25 mm and preferably 1.4 mm to 2.1 mm are used. The size of the panes can vary widely and depends on the use.

The intermediate layer contains or consists of at least one thermoplastic, preferably polyvinyl butyral (PVB), ethylene vinyl acetate (EVA) and/or polyethylene terephthalate (PET). The thermoplastic intermediate layer can also, for example, polyurethane (PU), polypropylene (PP), polyacrylate, polyethylene (PE), polycarbonate (PC), polymethyl methacrylate, polyvinyl chloride, polyacetate resin, casting resin, acrylate, fluorinated ethylene propylene, polyvinyl fluoride and / or ethylene Tetrafluoroethylene, or a copolymer or mixture thereof. The thermoplastic intermediate layer can be formed by one or more thermoplastic films arranged one above the other, the thickness of a thermoplastic film preferably being from 0.25 mm to 1 mm, typically 0.38 mm or 0.76 mm. The vehicle glazing can, for example, have a peripheral edge with a width of 2 mm to 50 mm, preferably 5 mm to 20 mm, which is not provided with the functional layer. The functional layer advantageously has no contact with the atmosphere and is protected from damage and corrosion, for example inside a vehicle glazing, by the thermoplastic intermediate layer.

The connection of the two individual panes of vehicle glazing during lamination is preferably carried out under the influence of heat, vacuum and/or pressure. Methods known per se can be used to produce vehicle glazing as a composite pane. For example, so-called autoclave processes can be carried out at an increased pressure of about 10 bar to 15 bar and temperatures of 130 ° C to 145 ° C for about 2 hours. Known vacuum bag or vacuum ring processes work, for example, at around 200 mbar and 80 ° C to 110 ° C. The two disks and the thermoplastic intermediate layer can also be pressed into a composite disk in a calender between at least one pair of rollers. Systems of this type are known for producing composite panes and usually have at least one heating tunnel in front of a press shop. The temperature during the pressing process is, for example, from 40 °C to 150 °C. Combinations of calender and autoclave processes have proven particularly useful in practice. Alternatively, vacuum laminators can be used. These consist of one or more heatable and evacuable chambers in which the two panes are laminated within, for example, about 60 minutes at reduced pressures of 0.01 mbar to 800 mbar and temperatures of 80 ° C to 170 ° C.

The invention further extends to a driver assistance system with an infrared-based monitoring function for the driver of a vehicle, which comprises an arrangement according to the invention. The driver assistance system further comprises at least one actuator and/or at least one signal output device, as well as an electronic control device, which is set up to determine information about the driver on the basis of an output signal from the radiation receiver and, on the basis of the determined information about the driver, to emit an electrical signal to the at least one actuator for carrying out a mechanical action and/or to the at least one signal output device for emitting an optical and/or acoustic signal. Furthermore, the invention extends to a method for monitoring a driver of a vehicle, in particular for implementation in a driver assistance system according to the invention, which comprises the following steps: a) emitting infrared radiation onto an infrared-reflecting functional layer of a vehicle glazing, such that infrared radiation reflected by the functional layer strikes the driver's face as first reflection radiation, wherein the first reflection radiation from the driver's face strikes the functional layer as second reflection radiation and is reflected by the functional layer as third reflection radiation, b) receiving the third reflection radiation, c) determining information about the driver, d) carrying out an action and/or outputting an optical and/or acoustic signal based on the determined information about the driver.

Furthermore, the invention extends to the use of the arrangement according to the invention in a driver assistance system of a vehicle, in particular a motor vehicle, for traffic on land, water or in the air, as well as to a vehicle with the arrangement according to the invention.

The various embodiments of the invention can be implemented individually or in any combination. In particular, the features mentioned above and those to be explained below can be used not only in the combinations given, but also in other combinations or on their own, without departing from the scope of the present invention.

The invention is explained in more detail below using an embodiment, with reference to the attached figures. Identical or equivalent elements are provided with the same reference numerals. They show in a simplified representation, not to scale:

Figure 1 is a schematic view of the front part of a vehicle with a driver with an arrangement according to the invention and a driver assistance system for infrared-based monitoring of the driver,

Figure 2 is a plan view of an embodiment of a vehicle glazing according to the invention, and

Figure 3 is a cross-sectional view of the vehicle glazing according to the invention. Figure 1 shows a schematic representation of an arrangement 1 according to the invention for a driver assistance system 100 of a vehicle 2, which enables monitoring of the driver by means of infrared radiation.

1 shows a driver 3 schematically on the steering wheel 4 of the vehicle 2, of which only the front part including the vehicle glazing 5 is shown as a windshield and console 6 for the sake of clarity. The driver assistance system 100 includes a radiation source 7 for emitting infrared radiation and a radiation receiver 8 for receiving infrared radiation, which are independent components but are usually arranged in the same assembly. The infrared radiation emitted by the radiation source 7 is directed at a functional layer 12, from there it is reflected onto the face 23 of the driver 3, from the face 23 of the driver 3 the infrared radiation is directed onto the functional layer 12 and from the functional layer 12 in the direction of the radiation receiver 8 reflected, where it is received by the radiation receiver 8.

The arrangement 1 further includes the radiation source 7 and the radiation receiver 8, which, shown schematically, can be arranged next to one another but installed in the same assembly. Both the radiation source 7 and the radiation receiver 8 are installed here, for example, in the rear area of the console 6, where they are practically not visible to the vehicle occupants. The radiation source 7 is positioned and aligned in such a way that the infrared radiation is directed onto the inner window 10 and is reflected there by the functional layer 12 as the first reflection radiation 14 to the face of the driver 3. The first reflection radiation 14 is reflected by the functional layer 12 only in a reflection area 22 of the windshield 5 and hits the face of the driver 3 from the front. The first reflection radiation 14 has a radiation component that hits the face of the driver 3 perpendicularly, ie in the horizontal direction , if the vehicle 2 is on a level surface. The first reflection radiation 14 is reflected from the face of the driver 3 as the second reflection radiation 15 in the direction of the functional layer 12. The second reflection radiation 15 has a radiation component that is reflected vertically from the face of the driver 3, ie in the horizontal direction if the vehicle 2 is standing on a flat surface. The second reflection radiation 15 is reflected from the functional layer 12 onto the radiation receiver s as the third reflection radiation 16. The third reflection radiation 16 is reflected by the reflection area 22 of the vehicle glazing 5. The radiation receiver 8 is on the Reflection area 22 directed and can receive the third reflection radiation 16 reflected by the functional layer 12.

The reflection region 22 preferably corresponds to a region of the vehicle glazing 5 (windshield) which is at least partially opposite the face of the driver 3, i.e. a region which results from a horizontal projection of the face 23 of the driver 3 onto the vehicle glazing 5.

Based on the driver data recorded in this way, information about the driver can be determined in a particularly reliable manner, since on the one hand the first reflection radiation 14 reflected by the functional layer 12 has a radiation component that strikes the driver's face 23 perpendicularly, and on the other hand that from the Functional layer 12 reflected third reflection radiation 16 has a radiation component that was reflected perpendicularly from the face 23 of the driver 3. Characteristics of the face, such as facial expressions and eye movements, can therefore be determined particularly well and reliably. In addition, the radiation source 7 and the radiation receiver 8 can be arranged in the rear area of the console 6 so that they can be easily integrated into the interior of the vehicle and do not disturb the design of the vehicle interior.

Figure 2 shows a plan view of an embodiment of the vehicle glazing 5 according to the invention. The functional layer 12 is electrically conductive. The electrically conductive functional layer 12 contains, for example, a silver layer with a layer thickness of 15 nm. It has a surface resistance of 0.69 ohms/square. A first busbar 20 and a second busbar 21 are applied to the electrically conductive functional layer 12 and are electrically connected to it.

The first strip-shaped busbar 20 is arranged essentially parallel to the upper edge O of the vehicle glazing 5 in the lower edge region of the vehicle glazing 5. In the case of a current bus conductor which is designed in the form of a strip, the longer of its dimensions is referred to as length and the less long of its dimensions is referred to as width. The length of the first current bus conductor 20 is 300 mm. The current bus conductor 20 extends over a length of less than 25% of the upper edge of the functional layer 12.

A second current collector 21 is arranged at a distance of approximately 645 mm from the first current collector 5.7'. The second current collector 21 runs essentially parallel to the first current collector 20. The second current collector 21 is arranged in the lower edge region R of the vehicle glazing 5. If a voltage is applied to the two current collectors 20, 21, a heating current flows through the zone of the electrically conductive functional layer 12 in between. A heating zone H is formed between the first and the second current collector 20, 21. The coated, transparent visible area of the vehicle glazing 5, in which the reflection area 22 is arranged, extends between the two current collectors 20, 21. The reflection area 22 is arranged between the two current collectors 20, 21. The length of the current collectors 20, 21 corresponds to the length of a side edge of the reflection area 22.

The first current collector 20 and second current collector 21 have a constant material thickness of, for example, approximately 10 pm and are made of silver. The first and second current collector 20, 21 are essentially the same length and the same width in this embodiment. The heating zone H formed between the first current collector 20 and the second current collector 21 extends over at least part of the area of the vehicle glazing 5 intended for viewing. The area of the reflection area 22 comprises less than 35% of the area of the heating zone (H).

The current collectors 20, 21 are adapted to the shape and curvature of the vehicle glazing 5. An average distance between the first current collector 20 and the second current collector 21 can be, for example, 645 mm. Furthermore, the second current collector 21 can have an average distance of, for example, 165 mm from the lower edge U of the vehicle glazing 5. The first current collector 20 can be connected to a positive potential of an electrical energy source (not shown). The second current collector 21 can be connected to the ground of the energy source. The first and second current collectors 20, 21 are each led to the energy source via connecting lines (not shown here), so that a voltage can be applied to the current collectors 20, 21.

The arrangement of the current collectors 20, 21 according to the invention makes it possible for the heating zone H to form only in a partial area of the functional layer 12. In this way, for example, electrical energy can be saved only by selectively heating the functional layer 12. The voltage source provides, for example, an on-board voltage that is usual for motor vehicles, preferably from 12 V to 15 V and, for example, about 14 V, which can also be converted to a higher voltage, for example via voltage converters. Particularly preferably, the voltage source can also have higher voltages, for example from 35 V to 45 V and in particular 42 V.

The first current bus conductor 20 and/or the second power bus conductor 21 are covered by a masking strip in the edge region R when viewed through the vehicle glazing 5 (viewing direction from the outside). The masking strip is opaque. The masking strip is applied to the interior, second surface II of an outer pane 9 (FIG. 3), but it can also be applied to the first surface III of the inner pane 10 (FIG. 3) or the second surface IV of the inner pane 10. The masking strip may be a peripheral (frame-shaped) layer which extends along the peripheral edge of the vehicle glazing. It also serves as UV protection for the assembly adhesive of the composite window (for example for gluing into a vehicle). The masking strip preferably has a transmittance for visible light of less than 15%, less than 10% or less than 1%. The masking strip can also be semi-transparent, at least in sections, for example as a dot grid, stripe grid or checkered grid. Alternatively, the masking strip can also have a gradient, for example from an opaque covering to a semi-transparent covering.

Figure 3 shows a rough cross-sectional view of the vehicle glazing 5 in the reflection area 22. The arrangement 1 according to the invention includes the vehicle glazing 5 (a windshield) of the vehicle 2, which has the outer pane 9 and the inner pane 10, which are firmly connected to one another by a thermoplastic intermediate layer 11 . The functional layer 12 or a carrier film with the functional layer 12 is arranged between the two panes 9, 10. In Figure 3, the functional layer 12 is applied to side III, i.e. on the surface III of the inner pane 10 facing the intermediate layer 11. Alternatively, the functional layer 12 can be arranged on side II, i.e. on the surface of the outer pane 11 facing the intermediate layer 11, or can be embedded between two thermoplastic intermediate layers 11. It would also be conceivable that the functional layer 12 has a sun protection effect.

The outer pane 9 contains soda lime glass and has a thickness of 2.1 mm. The inner pane 10 also consists of soda-lime glass and has a thickness of 1.6 mm or 1.5 mm. The two disks 9, 10 were laminated by a PVB film with a thickness of 0.76 mm. From the above statements it follows that the arrangement according to the invention for a driver assistance system of a vehicle advantageously enables a very precise determination of characteristics of a driver's face, in particular the recognition of facial expressions and eye movements. In contrast to conventional systems, even in poor weather conditions (fogging and icing on the inner window 10), the vehicle glazing can quickly be freed from moisture in an energy-efficient manner and reflect infrared radiation without interference.

Reference symbol list

1 Arrangement

2 vehicle

3 drivers

4 steering wheel

5 Vehicle glazing

6 console

7 radiation source

8 radiation receivers

9 Outer pane

10 Inner pane

11 intermediate layer

12 Functional layer

13 infrared radiation

14 first reflection radiation

15 second reflection radiation

16 third reflection radiation

17 Rearview mirror

18 A-pillar

19 Steering wheel column

20 first current collector

21 second current collector

22 Reflection area

23 face

100 driver assistance system

H Heating zone

R edge area

O top edge

U bottom edge

I first surface (outside) of the outer pane 9

II second surface (inside) of the outer pane 9

III first surface (outside) of the inner pane 10

IV second surface (inside) of the inner pane 10

Claims

Patent claims

1. Arrangement (1) for a driver assistance system (100) of a vehicle (2), comprising: a radiation source (7) for emitting infrared radiation (13), a radiation receiver (8) for receiving infrared radiation (16), vehicle glazing (5 ) having an outer pane (9) and an inner pane (10), which are connected to one another via a thermoplastic intermediate layer (11), the vehicle glazing (5) having at least one functional layer (12) reflecting infrared radiation and a reflection area (22), the Functional layer (12) is designed to be electrically conductive and is provided as a heating device for heating the vehicle glazing (5), with at least two current bus conductors (20, 21) being provided for electrically contacting the functional layer (12), with there being between the at least two current bus conductors (20 , 21) forms a heating zone (H) when an electrical voltage is applied to the two current bus conductors (20, 21), the reflection region (22) being arranged between the at least two current bus conductors (20, 21) and the length of a current bus conductor ( 20, 21) corresponds to the length of a side edge of the reflection area (22).

2. Arrangement (1) for a driver assistance system (100) of a vehicle (2) according to claim 1, wherein the reflection area (22) of the vehicle glazing (5) is arranged within the heating zone (H).

3. Arrangement (1) for a driver assistance system (100) of a vehicle (2) according to claim 1 or 2, wherein one of the at least two current bus conductors (20, 21) has a length of less than 50%, preferably less than 40%, particularly preferably extends from less than 30% of a side edge of the functional layer (12).

4. Arrangement (1) for a driver assistance system (100) of a vehicle (2) according to one of claims 2 to 3, wherein the area of the reflection region (22) is less than 50%, preferably less than 40%, particularly preferably less than 30% of the area of the heating zone (H).

5. Arrangement (1) for a driver assistance system (100) of a vehicle (2) according to one of claims 1 to 4, wherein the radiation source (7) is arranged such that infrared radiation (13) can be reflected from the functional layer (12) within the reflection region (22) as first reflection radiation (14) onto the face of a driver (3), the first reflection radiation (14) can be reflected from the face of the driver (3) as second reflection radiation (15) onto the functional layer (12), and wherein the radiation receiver (8) is arranged such that the second reflection radiation (15) reflected from the functional layer (12) within the reflection region (22) as third reflection radiation (16) is reflected to the radiation receiver (8) and can be received by the radiation receiver (8).

6. Arrangement (1) for driver assistance system (100) of a vehicle (2) according to claim 5, in which the radiation source (7) is arranged such that the first reflection radiation (14) has a radiation component that is perpendicular to the face (23). of the driver (3).

7. Arrangement (1) for driver assistance system (100) of a vehicle (2) according to one of claims 5 or 6, wherein the radiation receiver (8) is arranged such that third reflection radiation (16) can be received as reflected second reflection radiation (15), wherein the second reflection radiation (15) has a radiation component that was reflected perpendicularly from the face (23).

8. Arrangement (1) for driver assistance system (100) of a vehicle (2) according to one of claims 5 to 7, wherein the radiation source (7) is arranged so that the first reflection radiation (14) and the third reflection radiation (16) from the Reflection area (22) of the vehicle glazing (5) is reflected, which results at least partially from a horizontal projection of the driver's face (3) onto the vehicle window (5).

9. Arrangement (1) for driver assistance system (100) of a vehicle (2) according to one of claims 1 to 8, wherein the functional layer (12) is arranged on one side (III, IV) of the inner window (10).

10. Arrangement (1) for a driver assistance system (100) of a vehicle (2) according to one of claims 5 to 9, wherein the reflection region (22) is provided for reflecting the first reflection radiation (14) and the third reflection radiation (16).

11. Arrangement (1) for a driver assistance system (100) of a vehicle (2) according to one of claims 1 to 10, wherein the functional layer (12) is transparent to visible light and has one, two, three, four or more silver functional layers which are separated from one another by dielectric layers.

12. Driver assistance system (100) with infrared-based monitoring function for drivers (3) of a vehicle (2), comprising: an arrangement (1) according to one of claims 1 to 11, at least one actuator and / or at least one signal output device, an electronic control device , which is set up to determine information about the driver based on an output signal of the radiation receiver and, based on the determined information, to send an electrical signal to the at least one actuator for carrying out a mechanical action and / or to the at least one signal output device for outputting an optical and /or emit an acoustic signal.

13. Use of the arrangement (1) according to one of claims 1 to 11 in a driver assistance system with infrared-based monitoring of a driver (3) of a vehicle for traffic on land, on water or in the air.