Automotive lighting device with a segmented LED light source

Abstract

Motor vehicle lighting device with an LED light source having a plurality of individually controllable light source pixels, with control electronics set up for controlling the light source pixels, a light control unit and a communication interface device, wherein the light control unit is set up to generate control information for the control electronics and wherein the communication interface device is set up to transmit the control information to the control electronics.The automotive lighting device is characterized by the fact that the multitude of individually controllable light source pixels are divided into cluster pixels, that the lighting control unit is configured to generate individual control information for each cluster pixel, that the control information generated for each cluster pixel is the same for every light source pixel of the cluster pixel, and that the control electronics are configured to control all pixel light sources of the cluster pixel depending on the control information generated only for this cluster pixel.

Description

State of the art The present invention relates to a motor vehicle lighting device according to the preamble of claim 1. Such a motor vehicle lighting device is known per se and comprises an LED light source, control electronics, a lighting control unit, and a communication interface device. The LED light source has a plurality of individually controllable light source pixels. The control electronics are configured to control the light source pixels. The lighting control unit is configured to generate control information for the control electronics, and the communication interface device is configured to transmit the control information to the control electronics. LED light sources that feature a large number of individually controllable light source pixels are also referred to as pixel light sources. Examples of such pixel light sources are OLED panels or microLED light sources. These pixel light sources can have up to 100,000 individually controllable light source pixels and are controlled, for example, by a high-resolution video stream corresponding to the number or arrangement density of the light source pixels. The dimming of the individual light source pixels is achieved using pulse-width modulation (PWM) in the control electronics of the light source pixels. The necessary control information is transmitted via an image. This results in high costs throughout the entire control chain: An image is dynamically generated using powerful microcontrollers to create the desired light distribution. Furthermore, interfaces are used on both the hardware and software sides that require expensive hardware, e.g.Fiber optic cables, coaxial cables, and consequently expensive connectors for, e.g., transmission via GMSL (Gigabit Multimedia Serial Link). Also well-known and commonly used on the market are so-called matrix ADB systems (Adaptive Driving Beam systems). These matrix ADB systems currently feature up to approximately 150 light source pixels arranged in rows and columns. Each pixel is individually controlled with a relatively low resolution corresponding to this comparatively small number of pixels and dimmed using pulse-width modulation. This relatively small number of light source pixels is controlled by conventional lighting control units and interfaces, which are more cost-effective than the aforementioned high-performance microcontrollers and expensive hardware interfaces. From US2022 / 0388443 A1, it is known that when changes are made to the control of light source pixels, only the data of the pixels that have changed are transmitted. This leads to a reduction in the amount of data to be transmitted. The object of the invention is to provide a motor vehicle lighting device that is more cost-effective than the aforementioned motor vehicle lighting device, without being limited to the comparatively low resolution of the aforementioned matrix ADB systems. Disclosure of the invention This problem is solved by the sum of the features of claim 1. Its subject matter differs from the prior art mentioned above in that the plurality of individually controllable light source pixels is divided into cluster pixels, that the light control device is configured to generate cluster-pixel-specific control information for each cluster pixel, that the control information generated for each cluster pixel and transmitted by the communication interface is the same for each light source pixel of that cluster pixel, and that the control electronics are configured to control all light source pixels of that cluster pixel depending on the control information generated only for that cluster pixel. By grouping light source pixels into cluster pixels and thereby reducing the number of elements that the lighting control unit must individually control, the bandwidth required on the communication interface device is reduced, allowing the use of more cost-effective technologies. Control can be achieved, in particular, through cost-effective standard interfaces such as UART (Universal Asynchronous Receiver Transmitter), CAN (Controller Area Network), SPI (Serial Peripheral Interface), etc. Furthermore, existing lighting control units and their architecture and interfaces can be utilized, as these are currently used to control matrix lighting modules, which also incorporate pixel light sources. Grouping light source pixels into clusters in suitable areas and controlling these pixels together reduces the number of elements to be controlled, thus lowering the cost of the electronics. In particular, electronics originally designed for ADB modules with fewer pixels can be used. Expensive interfaces, such as those required for GMSL transmission, which necessitate expensive hardware like fiber optic cables, coaxial cables, and consequently expensive connectors, can be eliminated. Despite this saving on expensive interfaces and the use of lighting control units commonly found on the market for conventional matrix ADB systems, the invention allows the advantages of the LED light source with its multitude of light source pixels to be retained during the application phase, i.e., during the design of the automotive lighting device and its adaptation to its intended purpose. By transitioning from a large number of light source pixels to a comparatively smaller number of cluster pixels, the latter can also be controlled via standard interfaces such as UART, CAN, SPI, etc. However, this advantage comes at the cost of some resolution and flexibility, as the light source, with its numerous pixels, is less effective in applications such as those used in ADB headlights. In addition to reduced ADB resolution, this results in disadvantages when rendering symbols or other high-resolution structures using the light source. Furthermore, animations, for example, can no longer be displayed with the same resolution and design freedom as before the interconnection. A preferred embodiment provides that the control electronics determine which light source pixels are grouped into which cluster pixel. It is also preferred that the configuration be configurable. The configurable interconnection of light source pixels into cluster pixels further enables variable use of the light source, e.g., as a headlight source and as a light source for projecting symbols or information onto the roadway. Furthermore, it is preferred that the control electronics are set up to allow the configurable setting to be carried out by appropriate programming of the control electronics. Another preferred embodiment provides that the setting is achieved by connecting the light source pixels to be grouped together to a power supply via a switch. It is also preferred that the switches are software or hardware switches. Furthermore, it is preferred that the configuration is achieved by assigning the light source pixels to the switches. Another preferred embodiment provides that a segmentable LED light source can be variably adapted to its intended use by changing its arrangement. It is also preferred that the interconnection is programmed in such a way that it can change dynamically or can only change quasi-statically over a long period of time. It is further preferred that the motor vehicle lighting device is configured to change only parts of the assignment of light source pixels to cluster pixels or to completely replace one interconnection with another interconnection. Another preferred embodiment provides that the motor vehicle lighting device is configured so that the light source pixels within a cluster pixel can have different intensities. It is also preferred that these intensities are preferably configurable and changeable. It is further preferred that the motor vehicle lighting device is designed to control a lateral spread of a light distribution, i.e. a gradual transition from illuminated areas to non-illuminated areas. Another preferred embodiment provides that the motor vehicle lighting device is designed to generate animated light distributions. It is also preferred that the motor vehicle lighting device is configured to make a change by maintaining an existing interconnection, but the intensities of the individual light source pixels are variable. It is further preferred that light source pixels of a cluster pixel are connected to further, light source pixel-specific intensity switches, with which the brightness of the light source pixels can be controlled by the light control device or by the control electronics by means of pulse width modulation. Another preferred embodiment provides that the motor vehicle lighting device is configured to generate a representation of a pre-configured symbol, wherein the contours of the symbol are generated by luminous light source pixels in the cluster pixels. It is also preferred that differently pre-configured interconnections of individual light source pixels into cluster pixels are stored on a memory of the light source. The configurable interconnection of light source pixels to form cluster pixels also enables variable use of the light source, e.g. as a headlight light source and as a light source for projecting symbols or information onto the roadway. Further features and / or advantages will become apparent from the description and the accompanying figures. It is understood that the features mentioned above and those to be explained below can be used not only in the combinations specified, but also in other combinations or individually, without departing from the scope of the present invention. Drawings Exemplary embodiments of the invention are illustrated in the drawings and explained in more detail in the following description. In the figures, identical reference numerals denote identical elements or elements that are at least functionally equivalent. The figures show, each in schematic form: Fig. 1 an exemplary embodiment of a motor vehicle lighting device according to the invention; Fig. 2 a top view of a light-emitting surface of a cluster pixel comprising a plurality of light source pixels; Fig. 3 a top view of a light-emitting surface of an LED light source composed of cluster pixels; Fig. 4 a light-emitting surface of a cluster pixel comprising light source pixels with different brightness levels; and Fig. 5 a representation of a preconfigured symbol. Fig. 1 shows in detail a motor vehicle lighting device 10 comprising an LED light source 12, a control electronics unit 14, a lighting control unit 16, and a communication interface device 18. The LED light source 12 has a plurality of individually controllable light source pixels 20. Each light source pixel 20 is, for example, a light-emitting diode. The control electronics 14 is configured to control the light source pixels 20. The lighting control unit 16 is configured to generate control information for the control electronics 14, and the communication interface device 18 is configured to transmit the control information to the control electronics 14. A higher-level vehicle control unit 22 serves to control the vehicle lighting device 10 and requests, for example, the generation of light distributions such as a low beam distribution, a high beam distribution, or a coming home or leaving home light distribution from the vehicle lighting device 10. The requested light distribution is generated by controlling the light source pixels 20 and shaped and emitted by an optic 23, which may have one or more reflectors, lenses, or catadioptric optical elements. The multitude of individually controllable light source pixels 20 is divided into cluster pixels 24. Each cluster pixel 24 has a number of light source pixels 20 that together can form part of the requested light distribution, for example, a strip of a high beam distribution. The light control unit 16 is configured to generate cluster-pixel-specific control information for each cluster pixel 24. This control information, generated for each cluster pixel 24 and transmitted by the communication interface device 18, is identical for each light source pixel 20 of that cluster pixel 24, and the control electronics 14 are configured to control all light source pixels 20 of that cluster pixel 24 based on the control information generated specifically for that cluster pixel 24. Fig. 1 shows, as an embodiment of such an interconnection, that this can also be achieved in the control electronics 14 by jointly controlling the light source pixels 20 to be interconnected as a function of a signal from the light control unit 16 transmitted for these light source pixels 20 via the communication interface device 18. The number of light source pixels 20 is, for example, 1000 to 10000, and the number of cluster pixels is preferably 100 to 200. Which light source pixels 20 are to be functionally and structurally interconnected for this purpose depends on which light distribution is to be generated by the entire LED light source 12, or which luminous appearance is to be emitted from the light-emitting surface. Which light source pixels 20 are grouped into which cluster pixel 24 is preferably determined by the control electronics 14. This determination is preferably configurable and is preferably carried out by appropriate programming of the control electronics 14 during the manufacture or assembly of the automotive lighting device 10 in its production, for example at the end of the assembly line. The configuration is achieved by connecting the grouped light source pixels 20 together to a power supply 28 via a switch 26. The switches 26 can be software or hardware switches. Configuration is accomplished by assigning the light source pixels 20 to the switches 26. By changing this assignment, a segmentable LED light source can be variably adapted to its intended use. The interconnection of the high-resolution LED light source 20, which has a high number and arrangement density of light source pixels, to form a light source with a lower resolution and possibly a changed number of illuminated light source pixels 20 enables the LED light source 12 to be adapted to its intended use. Fig. 2 shows, as an example, a top view of a light emission surface of a cluster pixel 24 comprising 100 light source pixels 20. The segment-wise aggregation is carried out by the control electronics 14. Fig. 3 shows a light-emitting surface of an LED light source 12, which is composed of 100 cluster pixels 24. Each cluster pixel 24 has, for example, 100 light source pixels 20, as shown in Fig. 2. Each of the squares arranged in rows and columns 10 in Fig. 3 represents a cluster pixel 24, which in turn has ten by ten light source pixels 20, which are interconnected as a cluster pixel 24 and can be controlled by the light control unit 16 via the communication interface device 18. In one configuration, the interconnection can be programmed to change dynamically or to remain quasi-static over a long period. It is also possible to modify only parts of the assignment of light source pixels 20 to cluster pixels 24, or to completely replace one interconnection with another. Within a cluster pixel of 24, the light source pixels can have 20 different intensities. These intensities are also preferably configurable and modifiable. This allows, for example, the control and situational adjustment of a lateral slope in a light distribution, i.e., a gradual transition from bright areas to darkness. Animations can also be controlled. Another embodiment provides for the modification to be carried out by maintaining an existing interconnection, but changing the intensities of the individual light source pixels 20. To change the intensities of light source pixels 20 of a cluster pixel 24, these are connected to further, light source pixel-specific intensity switches 30, with which a pulse width modulation of the control by the light control unit 16 or by the control electronics 14 controls the brightness of the light source pixels 20. Fig. 4 shows a light-emitting surface of a cluster pixel where the grayscale levels represent the controlled brightness of the light source pixels. The bright stripes shown correspond to pixels that emit very little light, which can, for example, reduce glare for oncoming traffic. The cluster pixels 24 can be arranged, for example, as follows: For driving situations, light source pixels 20 of a headlight are combined into cluster pixels 24 to produce a glare-free high beam. For this purpose, the light source pixels 20 can be grouped together in the form of vertical stripes to create cluster pixels 24 in the high beam mode, so that the stripes where there is a risk of glare can be darkened. In the embodiment shown in Fig. 1, this is achieved by opening a cluster switch 26, which deactivates the light source pixels 20 that can be switched on and off together by this switch. Other light source pixels 20 of a headlight can be combined into square cluster pixels to create projections in front of the headlight. In the case of "coming home" and "leaving home" sequences, where headlights are automatically switched on or switched off with a delay when a vehicle is unlocked and / or locked via remote control, other light source pixels can be combined so that individual videos can also be displayed via the provided communication interface device and the LED light source. This application example, in particular, illustrates the flexible application possibilities that the invention enables despite its lower cost compared to the prior art mentioned above. The number of cluster pixels can be limited to, for example, 150, so that even common ADB lighting control units can be used. However, fewer or more cluster pixels than the aforementioned 150 can also be generated. Fig. 5 shows as a further example a representation of a symbol preconfigured using nine cluster pixels 24, wherein the contours of the symbol are generated by luminous light source pixels 20 in the nine cluster pixels. In a further embodiment, differently pre-configured combinations of individual light source pixels into cluster pixels can be stored in the memory of the light source or light source module. This allows the combination of light source pixels to be changed through simple configuration without requiring extensive information exchange between the ECU and the light source. These pre-configurable combinations can be defined, for example, on the production line. QUOTES INCLUDED IN THE DESCRIPTION This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature US 2022 / 0388443 A1

[0004]

Claims

Motor vehicle lighting device (10) with an LED light source (12) comprising a plurality of individually controllable light source pixels (20), with control electronics (14) configured for controlling the light source pixels (20), a light control unit (16) and a communication interface device (18), wherein the light control unit (16) is configured to generate control information for the control electronics (14) and wherein the communication interface device (18) is configured to transmit the control information to the control electronics (14), characterized in that the plurality of individually controllable light source pixels (20) is divided into cluster pixels (24), and that the light control unit (16) is configured to generate cluster pixel-specific control information for each cluster pixel (24).that the control information generated for each cluster pixel (24) and transmitted by the communication interface device (18) is the same for each light source pixel (20) of the respective cluster pixel (24), and that the control electronics (14) is configured to control all light source pixels (20) of the respective cluster pixel (24) depending on the control information generated only for that respective cluster pixel (24). Motor vehicle lighting device (10) according to claim 1, characterized in that the control electronics (14) determines which light source pixels (20) are grouped together to form which cluster pixel (24). Motor vehicle lighting device (10) according to claim 2, characterized in that the setting is configurable. Motor vehicle lighting device (10) according to one of claims 2 or 3, characterized in that the control electronics (14) is configured to allow the configurable setting to be carried out by a corresponding programming of the control electronics (14). Motor vehicle lighting device (10) according to one of claims 2 - 4, characterized in that the fixing is effected by the fact that the light source pixels (20) to be combined are each jointly connected to a power supply (28) by a switch (26). Motor vehicle lighting device (10) according to claim 5, characterized in that the switches (26) are software or hardware switches. Motor vehicle lighting device (10) according to claim 3, characterized in that the configuration is carried out by assigning the light source pixels (20) to the switches 26. Motor vehicle lighting device (10) according to claim 7, characterized in that a segmentable LED light source (12) can be variably adapted to its intended use by changing the assignment. Motor vehicle lighting device (10) according to one of the preceding claims, characterized in that the interconnection is programmed in such a way that it can change dynamically or can only change quasi-statically over a long period of time. Motor vehicle lighting device (10) according to claim 9, characterized in that it is configured to change only parts of the assignment of light source pixels (20) to cluster pixels (24) or to completely replace one interconnection with another interconnection. Motor vehicle lighting device (10) according to one of the preceding claims, characterized in that it is configured to allow the light source pixels (20) within a cluster pixel (24) to have different intensities. Motor vehicle lighting device (10) according to claim 11, characterized in that these intensities are preferably also configurable and changeable. Motor vehicle lighting device (10) according to one of the preceding claims, characterized in that it is configured to generate animated light distributions. Motor vehicle lighting device (10) according to claim 11, characterized in that it is configured to perform a change by maintaining an existing interconnection, but changing the intensities of the individual light source pixels (20). Motor vehicle lighting device (10) according to one of the preceding claims, characterized in that light source pixels (20) of a cluster pixel (24) are connected to further, light source pixel-specific intensity switches (30) with which the brightness of the light source pixels (20) can be controlled individually by the light control unit (16) or by the control electronics (14) by means of a pulse width modulation (32).

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