Lighting device and lighting system for a motor vehicle and method for operating a lighting system for a motor vehicle

Abstract

Lighting device (10) for a motor vehicle (100), comprising: - a processing module (1) which is configured to receive, process and transmit signals from a data bus (6) of the motor vehicle (100), and - an LED unit (3) configured to emit light with adjustable brightness and a predefined color point in an operational state, wherein the LED unit (3) comprises a microcontroller (4) and a plurality of LEDs (301, 302, 303, 304), wherein the microcontroller (4) and the LEDs (301, 302, 303, 304) are enclosed by a housing (7) of the LED unit (3), and wherein the LED unit (3) is further configured to communicate bidirectionally with the processing module (1) and to be operable as a light sensor, such that a current brightness value at the LED unit (3) can be determined by means of the LED unit (3) and the processing module (1), wherein the LED unit (3) comprises an additional light sensor (8) configured to measure a current brightness value at the LED unit (3) and to communicate bidirectionally with the processing module (1) to communicateso that the current brightness value at the LED unit (3) can be determined by means of the light sensor (8) and the processing module (1) independently of an operating state of the LEDs (301, 302, 303, 304) and the light sensor (8) is designed to communicate bidirectionally with the microcontroller (4) so ​​that the current brightness value at the LED unit (3) can be determined by means of the light sensor (8) and the microcontroller (4).

Description

[0001] The invention relates to a lighting device and a lighting system for a motor vehicle as well as a corresponding method for operating a lighting system, which enables a space-saving arrangement as well as a reliable and extended operation of the lighting device.

[0002] Lighting devices in motor vehicles with multicolor LED units (LED = "Light Emitting Diode") are known from the prior art. Such LED units typically comprise several single-color LEDs and are usually controlled by LED drivers to vary a desired brightness and color point (i.e., a mixed color). For this purpose, a module with a microprocessor is used, which handles communication with a motor vehicle data bus and drives the LED units, usually via PWM outputs (PWM = "Pulse-Width Modulation"). The so-called LIN bus (LIN = "Local Interconnect Network") is frequently used as the motor vehicle data bus.

[0003] Some multicolor LED units have an integrated circuit that, together with the single-color LEDs controlled via a data stream, is housed in a single casing. Parameters required for operating the individual LED units in lighting devices with multicolor LEDs are stored in a central processing module. US patent 9096168 B2 discloses a system for illuminating a vehicle interior in which several LEDs are arranged in a single casing and controlled by a controller to achieve homogeneous light distribution.

[0004] US2014 / 0055030 A1 concerns lighting systems and, in particular, a regulation of networks for lighting systems used in transit vehicles or means of transport such as buses or light rail vehicles.

[0005] US 2011 / 0309746 A1 concerns an LED lighting unit for a base for a vehicle lighting system that can be implemented and integrated into a vehicle design.

[0006] The object of the invention is to create a lighting device and a lighting system for a motor vehicle, as well as a corresponding method for operating a lighting system, which enable a space-saving arrangement and can contribute to a reliable and extended operation of the lighting device.

[0007] The problem is solved by the features of the independent patent claims. Advantageous embodiments are specified in the dependent claims.

[0008] According to a first aspect of the invention, a lighting device for a motor vehicle comprises a processing module configured to receive, process, and transmit signals from a data bus of the motor vehicle. The lighting device further comprises an LED unit configured to emit light with adjustable brightness and a predefined color point in an operational state. The LED unit includes a microcontroller and a plurality of LEDs, and the microcontroller and the LEDs are enclosed within a housing of the LED unit. The LED unit is further configured to communicate bidirectionally with the processing module and to function as a light sensor, so that a lighting function can be implemented and a current brightness value can be determined at the LED unit by means of the LED unit and the processing module.

[0009] The described lighting device not only enables space-saving lighting, for example, to illuminate a section inside or on a motor vehicle, but the described design also allows for retrieving a current brightness value at the location of the LED unit. This is achieved by using the LED unit in non-emitting mode to determine the ambient brightness. The LED unit is a semiconductor component that, in emitting mode, emits light of a predefined color when an electrical voltage or current is applied.

[0010] Furthermore, when the LEDs are not in operation, the LED unit can function as a semiconductor diode, similar to a photodiode. This allows for the generation of an electric current or voltage based on light exposure, enabling the determination of the current brightness value at the LED unit's location. The processing module allows for targeted control of the LED unit and retrieval of its current brightness value. Due to the described design and communication capabilities, each individual LED unit can be controlled and its current brightness value can be retrieved independently.

[0011] In this way, the LED unit capable of illumination can be further used to collect data that, in connection with the LED unit, contains information about ambient brightness. The described lighting device thus implements an arrangement that enables desired illumination by controlling the LED unit and, due to its bidirectional communication capability, allows data to be read back from the LED unit.

[0012] The lighting device is intended for use in a motor vehicle, such as a passenger car and, if applicable, a truck. Preferably, the lighting device comprises several LED units, each including a microcontroller and several LEDs integrated within a common housing. A single LED unit thus constitutes a semiconductor device, which, due to its internal microcontroller, can also be referred to as a "smart" LED.

[0013] Preferably, each LED unit is connected to an internal data bus (i.e., a data bus within the lighting device), which in turn is coupled to the processing module. Signals can be received, processed, and sent via the processing module. Such signals include, for example, external control commands from an automotive data bus, which can be converted into internal control commands by the processing module and fed onto the internal data bus to adjust the brightness and color position of one or more LED units. The internal data bus can be, for example, an SPI data bus (SPI = "Serial Peripheral Interface") or, if necessary, another data bus, such as a differential data bus, which encodes digital data via a voltage difference between two lines.The vehicle data bus can be, for example, a LIN bus (LIN = "Local Interconnect Network") or a CAN bus (CAN = "Controller Area Network").

[0014] The one or more LED units are each adjustable in terms of their brightness (i.e., light intensity) and emit light with a predefined color coordinate. The term "color coordinate" describes the color of the emitted light and can be monochromatic or a mixed color produced by the respective LED unit. The color coordinate can be specified, for example, as a position on a colorimetric diagram, particularly a colorimetric diagram of the CIE standard colorimetric system (CIE = "Commission internationale de l'éclairage").

[0015] For example, an LED unit can have several LEDs, each emitting blue light or light of a different color or wavelength. In the latter case, the LED unit becomes a multi-color LED unit with adjustable color coordinates. Each LED unit, as a single semiconductor component, preferably comprises at least three single-color LEDs of different colors, housed together with the LED unit's microcontroller in a common semiconductor component package. The structure of such a semiconductor component enables a predefined light emission based on the electronic properties of the semiconductor and can also be operated in reverse, functioning as a brightness or light sensor. The described LED unit can thus be used as a light sensor in a non-illuminating state, allowing the LED unit to measure the current (i.e., ambient light level) of the LED.The brightness value (currently available) can be measured at the respective LED unit and can be provided to the processing module and / or the microcontroller.

[0016] Depending on the current brightness level of each LED unit, it can be selectively controlled by the microcontroller, thus contributing to the reliable and efficient operation of the lighting device. Based on controlling the operating current of each LED within an LED unit, each LED in the unit can be individually controlled by the microcontroller, for example, via pulse-width modulation. By determining and retrieving the current brightness level of the LED unit, information about the local ambient light at the LED unit's location can be obtained and incorporated into the light-emitting operation of the lighting device. For example, the brightness of each LED unit can be adjusted to the determined current brightness level to create a particularly attractive lighting pattern.

[0017] By directly integrating a microcontroller and multiple LEDs within a single LED unit, the current brightness value at the unit's location can be precisely measured. This allows for immediate responses to voltage and brightness variations, enabling internal adjustments and compensation within the LED unit during operation. Furthermore, the data collected by the processing module can be further processed, allowing for features such as color gradients and color changes to be applied via the microcontroller. The LED unit's data, containing information about the current brightness value, can be referred to as measurement signals. These signals are processed internally, primarily by the microcontroller, and / or made available for external processing, particularly by the processing module.

[0018] The described lighting device thus incorporates a multitude of functions, each integrated into a semiconductor package of an LED unit. This reduces the required wiring between the LED unit and the processing module, allowing the processing module itself to be designed smaller as a control controller. In this way, a space-saving design for the lighting device can be achieved, which is advantageous for potential installation positions in or on a vehicle. This space saving is particularly evident in lighting devices with a large number of LED units.

[0019] Due to the described design of the lighting device and the bidirectional communication capability of the LED unit, the communication rate decreases while the data transmission speed increases. In this way, the lighting device can make a beneficial contribution to electromagnetic compatibility in a motor vehicle. Furthermore, interface costs can be reduced because they can be made smaller. The lighting device retains its video capability, as a sufficient number of frames per second can be transmitted.

[0020] The data collected by the lighting device for each LED unit can also contribute to maintaining or improving the so-called ASIL standard (ASIL = "Automotive Safety Integrity Level"). This standard aims to guarantee a specified basic level of safety.

[0021] The LED unit includes an additional, separate light sensor designed to measure the current brightness level at the LED unit and communicate bidirectionally with the processing module. This allows the light sensor and processing module to determine the current brightness level at the LED unit independently of the LEDs' operating state. In this way, the current brightness level at the LED unit can be determined and retrieved independently of controlling and operating the individual LEDs. Therefore, the processing module and light sensor can collect data and query the current brightness level at any time.

[0022] Due to its described design, the lighting device can be used beyond its lighting function to collect data on ambient brightness at the location of each LED unit. Determining the current brightness value can also be performed while the LEDs are illuminated and, for beneficial operation of the lighting device, can be integrated into the activation of the lighting function to implement brightness-dependent control of the respective LED unit. In this way, the operating control of the LED unit can be adapted to current and local ambient conditions based on brightness. For example, a set color point and brightness can be kept as constant as possible during operation of the respective LED unit.Thus, taking into account local light and shadow conditions of the individual LED units, a desired brightness and a predetermined color point can be set individually and precisely, resulting in a consistent appearance of the lighting device.

[0023] The light sensor can be positioned separately within the LED unit's housing, either isolated from or shaded by the LEDs, or within the range of the LEDs' emitted light. This allows the sensor to incorporate the LEDs' light output into brightness measurements and, for example, verify their functionality. If one or more LEDs are too bright, the sensor can adjust or correct the current by increasing it to achieve the desired brightness. Brightness measurement using the light sensor can be based on established technologies. For instance, the sensor can detect brightness using a quasi-short circuit, resistance measurement, infrared, or a diode.

[0024] The light sensor is designed to communicate bidirectionally with the microcontroller, so that the current brightness value at the LED unit can be determined using the light sensor and the microcontroller.

[0025] According to a further development of the lighting device, the microcontroller and the processing module are designed to communicate bidirectionally. The processing module is specifically configured to communicate with the LED unit, particularly with the microcontroller, and with the separate light sensor of each LED unit, and to retrieve a current brightness value. This communication includes receiving and sending data and can take place directly between the respective communication-capable components. Using the processing module, each LED unit or each light sensor of a respective LED unit can be accessed individually, thus enabling a high degree of scalability for the lighting device.

[0026] According to a further development of the lighting device, the LED unit is configured as a multicolor LED unit, and the individual LEDs are configured as single-color LEDs. According to a further development of the lighting device, the LED unit comprises an RGB LED unit and / or an RGBW LED unit. An RGB LED unit comprises, in a manner known per se, a red, green, and blue single-color LED, and an RGBW LED unit comprises, in addition to a red, green, and blue LED, a white LED.

[0027] According to a further development of the lighting device, the LED unit has a temperature sensor designed to measure the current temperature value at the LED unit and communicate bidirectionally with the processing module, so that the current temperature value at the LED unit can be retrieved or determined via the temperature sensor and the processing module. The temperature sensor can also be used to collect further data from the LED unit, which can contribute to the reliable and extended operation of the lighting device.

[0028] The temperature sensor is located within the housing of the respective LED unit and, similar to the previously described separate light sensor, can be controlled by the processing module and / or the associated microcontroller. Thus, the described lighting device serves to implement a lighting function and functional sensor technology, utilizing available installation space to acquire or collect additional data. The LED technology of the lighting device is therefore useful for illumination, light or brightness measurement, and, if necessary, temperature measurement, and allows for data retrieval even if, for example, an electrical voltage is temporarily interrupted. In such a case, a previous state can be retrieved.Due to the described design of the lighting device or individual LED units, the processing module, acting as a control module, can be smaller, further contributing to a clear and space-saving design. Furthermore, by using a large number of LED units installed in and / or on a vehicle, correlations across a vehicle group can be determined, and information about the local characteristics of each individual LED unit can be obtained.

[0029] According to a further aspect of the invention, a lighting system for a motor vehicle comprises at least one embodiment of the previously described lighting device and the motor vehicle itself. The lighting device is, in particular, arranged and installed in or on the motor vehicle and provides interior and / or exterior lighting. The motor vehicle may also have several embodiments of the described lighting device, one of which, for example, is arranged in and another on the motor vehicle, each implementing a corresponding lighting function. This allows for the generation of attractive lighting effects with a homogeneous appearance. Furthermore, the lighting device enables the retrieval of a current brightness value at the respective LED unit, and, with an additionally integrated light sensor, also independently of the operating state of the LEDs and any activated lighting function.Since the lighting system comprises at least one embodiment of the previously described lighting device, all features and properties of the lighting device are also disclosed for the lighting system and vice versa.

[0030] According to a further aspect of the invention, a method for operating an embodiment of the previously described lighting system for a motor vehicle comprises controlling the LED unit by means of the processing module to determine a current brightness value at the LED unit and receiving measurement signals from the LED unit.

[0031] The procedure further includes determining a current brightness value at the LED unit depending on the received measurement signals from the LED unit and controlling a function of the motor vehicle depending on the determined brightness value at the LED unit.

[0032] The described method allows for the retrieval of a current brightness value at the location of the respective LED unit of the lighting system or lighting device, so that, for example, an ambient brightness value can be determined at the respective LED unit. Controlling a function of the vehicle can include the operation of the LED unit or the lighting function of the lighting device, but the described method also allows for the control of a function based on the determined brightness value, in addition to the light-emitting operation of the LED unit.

[0033] The data collected by the LED unit is gathered and analyzed by the processing module or made available for later processing. The measured brightness value can, for example, be stored in the vehicle's own database or an external database and used for further analysis, such as determining a brightness profile. The measured brightness value can also be used to adjust the lighting function of the lighting device or to influence another lighting function in or on the vehicle based on the measured brightness value.

[0034] The microcontroller is designed, for example, in such a way that if the current brightness value exceeds or falls below a predefined threshold, it communicates with the processing module and provides an output which is converted into an external control command for the vehicle data bus and enables the activation or deactivation of instrument panel lighting or headlights.

[0035] Furthermore, depending on one or more measured brightness values, the brightness of various light-emitting displays can be controlled individually or in combination. Examples of such displays include a head-up display, button backlighting, the illumination of a rear-seat entertainment system, and a central information display (CID). Additionally, individual light-emitting displays can be controlled independently based on one or more measured brightness values, which can be particularly useful due to specific local conditions in or on the vehicle. For example, this might be the case with more intense sunlight on one side, allowing the brightness of a display or ambient lighting on the passenger side to be increased or decreased.The inclusion of local characteristics in the control of various functions is made possible by the fact that, as a rule, a multiple LED units are distributed in and / or on the vehicle and can be used for brightness measurement.

[0036] Retrieving or determining a current brightness value at the position of the LED unit can be performed continuously, at predetermined time intervals, or depending on an instruction. Since the method for operating an embodiment of the previously described lighting system or lighting device includes all features and properties of the lighting device, all features and properties of the lighting device are also disclosed for the method of operating the lighting system, and vice versa.

[0037] The procedure further includes controlling the additional light sensor by means of the processing module to determine the current brightness value at the LED unit, so that, depending on the received measurement signals from the light sensor, a brightness value is determined at the location of the LED unit and a function of the motor vehicle is controlled depending on the determined brightness value.

[0038] The method can further include controlling the temperature sensor by means of the processing module to determine a current temperature value at the LED unit, so that, depending on received measurement signals from the temperature sensor, a temperature value is determined at the location of the LED unit and a function of the motor vehicle is controlled depending on the determined temperature value.

[0039] Exemplary embodiments of the invention are explained in more detail below with reference to the schematic drawings. These show: Fig. 1 An embodiment of a lighting system for a motor vehicle in a schematic top view, Fig. 2 an embodiment of a lighting device for a motor vehicle in a schematic representation, Fig. 3 an embodiment of an LED unit of the lighting device according to Fig. 2 in a detailed view.

[0040] Elements of the same construction or function are marked with the same reference symbols across all figures. For the sake of clarity, not all depicted elements may be marked with their corresponding reference symbols in every figure.

[0041] Fig. Figure 1 schematically illustrates in a top view a lighting system 110, which comprises a motor vehicle 100 and a lighting device 10 with a plurality of LED units 3. The LED units 3 are each coupled to an internal data bus 2, which in turn couples the LED units 3 to a processing module 1. The processing module 1 is in turn coupled to a motor vehicle data bus 6.

[0042] As shown in the following Fig. 2 and Fig. As explained in more detail in section 3, the lighting device 10 or the lighting system 110 enables a space-saving lighting function, for example to illuminate a section in or on the motor vehicle 100, and also to determine a current brightness value at the location of a respective LED unit 3.

[0043] Fig. Figure 2 schematically represents an embodiment of the lighting device 10, which, for example, as shown in Fig. Figure 1 illustrates the motor vehicle 100 having interior lighting. Alternatively, the lighting device 10 can be arranged as exterior lighting on the motor vehicle 100, or the lighting system 110 can comprise several lighting devices 10 that are installed in and / or on the motor vehicle 100.

[0044] The lighting device 10 comprises a plurality of multicolor LED units 3 arranged on a strip as its light source. These multicolor LED units 3, which are hereinafter also simply referred to as LED units 3, each constitute a single semiconductor device with several single-color LEDs 301-304 and a microcontroller 4. The single-color LEDs 301-304 and the microcontroller 4 are enclosed in a housing 7 of each LED unit 3. In one embodiment of the lighting device 10, these components are integrated together with a light sensor 8 in the housing 7 of the semiconductor device (see Figure 1). Fig. 3) For example, the single-color LED 301 is configured as a red LED, the single-color LED 302 as a green LED, the single-color LED 303 as a blue LED, and the single-color LED 304 as a white LED. The color designations refer to the color or wavelength or wavelength range of the light emitted by the respective LED. With the ribbon-like arrangement of the LED units 3, a very high packing density can be achieved (depending on the housing design, for example, from 144 to 367 LEDs / m), thus enabling a space-saving design using the lighting device 10.

[0045] The individual LED units 3 are controlled via a digital data stream in the form of a bitstream, which is supplied to the individual LED units 3 via the internal data bus 2 of the lighting device 10. The internal data bus 2 comprises a line CL for the clock signal and a line DL for the bitstream.

[0046] The signals on the internal data bus 2 originate from the processing module 1, which is connected to the vehicle data bus 6 of the vehicle 100. The processing module 1 comprises a LIN transceiver 101, which taps the corresponding digital signals from the vehicle data bus 6 to control the LED units 3, and a microprocessor 102, which converts the tapped signals into corresponding data signals on the data line DL of the internal data bus 2. The signals transmitted on the vehicle data bus 6 include signals intended for the lighting device 10 and define a light pattern to be set for the lighting device 10.

[0047] These signals originate from a control unit of the vehicle 100, which, for example, determines the light pattern to be generated based on driver input and transmits the corresponding signal to the vehicle data bus 6. The processing module 1 detects whether the light pattern corresponding to the current signal on the vehicle data bus 6 is intended for the lighting device. If so, the signal is converted by the microprocessor 102 into a corresponding signal for the internal data bus 2.

[0048] The vehicle data bus 6 is, for example, a LIN bus (LIN = "Local Interconnect Network"). The internal data bus 2 can, for example, be an SPI bus (SPI = "Serial Peripheral Interface"). Preferably, the signals for the internal data bus 2 are generated by the microprocessor 102 using SPI software. SPI software is a program library that allows any free pins of the microprocessor 102 to be used for outputting signals to the SPI bus. Alternatively, SPI hardware can also be used. In this case, special SPI pins are provided for outputting signals to the SPI bus. The use of SPI software is advantageous because the internal data bus 2 can have several lines DL and CL for controlling a larger number of LED units 3. As an alternative to an SPI bus, the internal data bus 2 can also be configured as a differential data bus or as any other type of data bus.A differential data bus is characterized by the fact that it encodes digital data via a voltage difference between two lines.

[0049] In the embodiment according to Fig. In addition to lines CL and DL, two power lines L1 and L2 are provided, which are connected to a DC power supply 5. Based on the bitstream received via data line DL, pulse width modulation (PWM) of the current supplied to the individual LEDs 301-304 is performed in order to control the LEDs 301-304 according to the bitstream on data line DL.

[0050] The structure of a single LED unit 3 according to the Fig. 1 and Fig. 2 is detailed in Fig. Figure 3 illustrates this. The components of the LED unit 3 shown are integrated into a single semiconductor device. The signals from the internal data bus 2 are received via a communication interface COM of the LED unit 3. The clock signal from the clock line CL is forwarded to the microprocessor 401 described below, while the data stream from the data line DL, after decoding in the communication interface COM, is fed to 8-bit shift registers SR0-SR4. The value output by shift register SR0 indicates the desired overall brightness of the LED unit 3, whereas the values ​​of shift registers SR1 to SR4 output the color components of the individual single-color LEDs 301-304 to generate the desired mixed color.In particular, the color component of the red-emitting LED 301 is output via the shift register SR1, the color component of the green-emitting LED 302 via the shift register SR2, the color component of the blue-emitting LED 303 via the shift register 303, and the color component of the white-emitting LED 304 via the shift register 304.

[0051] The values ​​of the individual shift registers are fed to the microcontroller 4, which has a logic module or microprocessor 401 and an associated non-volatile EEPROM memory 402. This memory 402 can, in particular, contain calibration data originating from a calibration process of the LED unit 3. This data determines, for a predefined standard temperature value of the LED unit 3, how the operating currents of the individual single-color LEDs 301-304 are to be set so that the overall brightness value from shift register SR0 and the color mixing (i.e., the corresponding color coordinates) are achieved according to the values ​​from shift registers SR1 to SR4.

[0052] The microprocessor 401 accesses the values ​​stored in memory 402 and can receive a current brightness value via a light sensor 8, which is integrated into the semiconductor component of the LED unit 3. In an alternative embodiment of the lighting device 10, one or more LED units 3 do not have a separate light sensor, but, due to their semiconductor design, allow a current brightness value to be determined and retrieved at the position of the respective LED unit 3. The LED unit 3 is a semiconductor component that, in emitting mode, emits light of a predefined color when an electrical voltage or current is applied.Furthermore, when LEDs 301-304 are not in operation, LED unit 3 can be operated as a semiconductor diode, like a photodiode. This allows an electric current or voltage to be generated based on light exposure, enabling the determination of the current brightness value at the location of LED unit 3. The processing module 1 allows for the targeted control of each individual LED unit 3 and the retrieval of its current brightness value.

[0053] Controlling the respective LED unit 3 and retrieving or determining a current brightness value at the position of the LED unit 3 can include controlling one or more of the LEDs 301-304, so that, for example, in a non-emitting operation of the LED unit 3, the LEDs 302 and 304 are specifically controlled by means of the processing module 1 in order to determine a current brightness value of the ambient light.

[0054] Each LED unit has 3 indicators, such as Fig. Figure 3 illustrates an additional light sensor 8, so that the current brightness value at the LED unit 3 can be determined and retrieved independently of the control and operation of the respective LEDs 301-304, so that data can be collected and a current brightness value can be queried at any time by means of the processing module 1 and the light sensor 8.

[0055] For example, the microprocessor 401 contains a temperature and / or brightness algorithm which, by accessing the memory 402, determines the corresponding operating currents for the above-mentioned standard temperature value and appropriately corrects these operating currents if the current brightness value from the light sensor 8 deviates from the standard temperature value.

[0056] In this way, a desired brightness and a predefined color coordinate can be controlled and adjusted to the ambient light brightness according to the values ​​from the shift registers SR0-SR4, in order to achieve a desired and appealing light pattern using the lighting device 10. The temperature algorithm of the microprocessor 401 thus takes into account the fact that the brightness at the location of the LED unit 3 can affect the external appearance, so that a brightness-dependent correction can be performed to achieve a desired brightness and color coordinate.

[0057] The light sensor 8 is designed to communicate with the processing module 1 via the COM communication interface. This communication involves receiving and sending signals or data between the respective components. In this way, the processing module 1 and the light sensor 8 can determine and retrieve the current brightness value at the location of the respective LED unit 3.

[0058] For example, the processing module 1 queries the light sensor 8 for the current brightness value at predefined time intervals, so that the light sensor 8 measures the brightness and provides the measurement signals to the processing module 1. Alternatively or additionally, communication between the processing module 1 and the light sensor 8 can take place via the microcontroller 401 of the respective LED unit 3, which is coupled to the processing module 1 and the light sensor 8 via signal technology and enables bidirectional communication between the two components.

[0059] In this way, precise brightness measurement at the location of the LED unit 3 can be carried out using the light sensor 8 even when the lighting function is inactive. Furthermore, the operation of the individual multicolor LED units 3 of the lighting device 10 can be individually and precisely adjusted to the current local brightness. The operating currents for the individual LEDs 301-304 are supplied via a voltage regulator RE, which consists of the in Fig.The positive voltage VDD and the negative voltage VSS are supplied to the voltage supply 5 shown in Figure 2. The microprocessor 401 also generates a clock signal for a corresponding oscillator OS, which is fed to PWM generators G1-G4. The operating currents of the individual LEDs 301-304 are generated in generators G1 to G4 via pulse-width modulation. The operating current values ​​derived from the temperature and / or brightness compensation algorithm are sent by the microprocessor 401 to the individual generators G1-G4. Generator G1 generates the current for the red-emitting LED 301, generator G2 the current for the green-emitting LED 302, generator G3 the current for the blue-emitting LED 303, and generator G4 the current for the white-emitting LED 304 using pulse-width modulation.The PWM signals generated by the individual generators, which reach the single-color LEDs 301-304 via the current output CO, then set the corresponding light with the desired brightness and color position for LED unit 3 according to the signal that reaches LED unit 3 via the internal data bus 2.

[0060] By means of the described lighting device 10 and the lighting system 110, the light-emitting operation as well as other functions of the motor vehicle 100 can be usefully controlled. For example, in addition to the lighting function, the illumination of a dashboard of the motor vehicle 100 or the emission of light by means of a headlight of the motor vehicle 100 can be activated, deactivated or dimmed depending on one or more determined brightness values ​​in order to achieve useful and attractive lighting by means of the respective component. Reference symbol list 1 processing module 10 Lighting device 100 motor vehicles 101 LIN transceivers 102 microprocessor 110 Lighting system 2 internal data bus 3 multi-color LED units 301-304 Single-color LEDs 4 microcontrollers 401 Microprocessor 402 EEPROM 5 Power supply 6 Motor vehicle data bus 7 Housing of the LED unit 8 light sensor CL line for clock signal CO power output COM communication interface DL data line G1-G4 PWM generators L1-L2 power lines OS oscillator RE voltage regulator SR0-SR4 shift registers VDD, VSS voltages

Claims

[1] Lighting device (10) for a motor vehicle (100), comprising: - a processing module (1) which is configured to receive, process and transmit signals from a data bus (6) of the motor vehicle (100), and - an LED unit (3) configured to emit light with adjustable brightness and a predefined color point in an operational state, wherein the LED unit (3) comprises a microcontroller (4) and a plurality of LEDs (301, 302, 303, 304), wherein the microcontroller (4) and the LEDs (301, 302, 303, 304) are enclosed by a housing (7) of the LED unit (3), and wherein the LED unit (3) is further configured to communicate bidirectionally with the processing module (1) and to be operable as a light sensor, such that a current brightness value at the LED unit (3) can be determined by means of the LED unit (3) and the processing module (1), wherein the LED unit (3) comprises an additional light sensor (8) configured to measure a current brightness value at the LED unit (3) and to communicate bidirectionally with the processing module (1) to communicateso that the current brightness value at the LED unit (3) can be determined by means of the light sensor (8) and the processing module (1) independently of an operating state of the LEDs (301, 302, 303, 304) and the light sensor (8) is designed to communicate bidirectionally with the microcontroller (4) so ​​that the current brightness value at the LED unit (3) can be determined by means of the light sensor (8) and the microcontroller (4). [2] Lighting device (10) according to claim 1, wherein the microcontroller (4) and the processing module (1) are configured to communicate bidirectionally with each other. [3] Lighting device (10) according to one of claims 1 or 2, wherein the LED unit (3) is a multicolor LED unit and the LEDs (301, 302, 303, 304) are each single-color LEDs. [4] Lighting device (10) according to any one of claims 1 to 3, wherein the LED unit (3) comprises an RGB LED unit and / or an RGBW LED unit. [5] Lighting device (10) according to one of claims 1 to 4, wherein the LED unit (3) comprises a temperature sensor configured to measure a current temperature value at the LED unit (3) and to communicate bidirectionally with the processing module (1), so that the current temperature value at the LED unit (3) can be determined by means of the temperature sensor and the processing module (1). [6] Lighting system (110) for a motor vehicle (100), comprising: - the motor vehicle (100), and - at least one lighting device (10) according to one of claims 1 to 5. [7] Lighting system (110) according to claim 6, wherein the lighting device (10) is arranged in the motor vehicle (100) and is designed as interior lighting. [8] Lighting system (110) according to claim 6 or 7, wherein the lighting device (10) is arranged on an outside of the motor vehicle (100) and is designed as exterior lighting. [9] Method for operating a lighting system (110) for a motor vehicle (100) according to any one of claims 6 to 8, comprising: - Controlling the LED unit (3) by means of the processing module (1) to determine a current brightness value at the LED unit (3), - Receiving measurement signals from the LED unit (3), - Determining a current brightness value at the LED unit (3) depending on the received measurement signals of the LED unit (3), and - Controlling a function of the motor vehicle (100) depending on the determined brightness value at the LED unit (3), the method further comprising: - Controlling the light sensor (8) of the LED unit (3) by means of the processing module (1) to determine a current brightness value at the LED unit (3), - Receiving measurement signals from the light sensor (8), - Determining a current brightness value at the LED unit (3) depending on the received measurement signals from the light sensor (8), and - Controlling a function of the motor vehicle (100) depending on the determined brightness value at the LED unit (3). [10] The method of claim 9, comprising: - Controlling the temperature sensor of the LED unit (3) by means of the processing module (1) to determine a current temperature value at the LED unit (3), - Receiving measurement signals from the temperature sensor, - Determining a current temperature value at the LED unit (3) depending on the received measurement signals from the temperature sensor, and - Controlling a function of the motor vehicle (100) depending on the determined temperature value at the LED unit (3).

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