Lighting control device

Abstract

Lighting control device, which includes: a control unit (11, 12) that controls the light emission states of luminaires, each with different light emission colors, such that a cabin is illuminated by emitted light emitted by a plurality of light sources (21, 22, 23, 24) and having a predetermined chromaticity, wherein each of the light sources (21, 22, 23, 24) has the luminaires, wherein the control unit (11, 12) controls the light emission states of the luminaires according to an externally input correction coefficient in order to adjust the chromaticity of the emitted light, and a prior control unit (11, 40) which, for each of the plurality of light sources (21, 22, 23, 24), receives a signal expressing the chromaticity measured by a chromaticity measuring instrument arranged in the vicinity of the respective light source (21, 22, 23, 24) for measuring the chromaticity of the emitted light, calculates the correction coefficient for each of the plurality of light sources (21, 22, 23, 24) in accordance with a difference between the predetermined chromaticity and the measured chromaticity and transmits the calculated correction coefficients to the control unit (11, 12), wherein the control unit has a calibration mode which is to be executed when the chromaticity measuring instruments measure the chromaticity, wherein the control unit (11, 12) controls the light sources (21, 22, 23, 24) to a predetermined reference light emission state in the calibration mode, and wherein the control unit (11, 12) controls the plurality of light sources (21, 22, 23, 24) each in accordance with a plurality of different light emission patterns in the calibration mode, wherein each of the plurality of light emission patterns consists of a combination of red light emissions, green light emissions, blue light emissions and white light emissions, and where the duration of the delay time between an emission of white light and an emission of blue, red, or green light differs from one light emission pattern to another.

Description

CROSS-REFERENCE TO RELATED REGISTRATIONS

[0001] The present application is based on Japanese patent application No. 2015-211039 dated October 27, 2015, the contents of which are incorporated herein by reference. BACKGROUND OF THE INVENTION 1. Field of Invention

[0002] The present invention relates to a lighting control device that can be used for lighting a vehicle, etc. 2. State of the art

[0003] For example, imagine a cabin in a vehicle, such as a passenger car, that needs lighting. In this case, the cabin should be illuminated with a light source with the correct chromaticity to match the conditions at that time. For such an application, a full-color LED device containing multiple LED elements, each emitting light with red (R), green (G), and blue (B) wavelengths, is used as the light source. This allows for lighting with different chromaticities to be provided as needed.

[0004] German patent application DE 10 2006 037 292 A1 describes a light source with a plurality of LEDs and a sensor for measuring the light emitted by the LEDs. The light emission is controlled (calibrated) using a feedback system in which a target value for the light emission of a specific LED is compared with a corresponding current measurement.

[0005] German patent application DE 10 2007 044 556 A1 describes a method for temperature-dependent adjustment of the colorimetric or photometric properties of an LED lighting device with LEDs that emit light in different colors. A temperature-dependent correction is determined based on luminance and spectral measurements and comparison with a target value.

[0006] US patent application US 2013 / 0026940A1 describes a self-identifying modulated light source in which visible light produced by an investigator (LED) is modulated to represent an identification code of the light source.

[0007] Furthermore, a prior art technique for calibrating a lighting device is described, for example, in JP 2007 - 59 179 A. In the lighting device of JP 2007 - 59 179 A, ​​an illumination light is directed towards an illumination / chromaticity calibration tool equipped with an RGB color pattern. The intensities of the lights emitted by corresponding color LED groups are obtained in accordance with the corresponding R, G, and B color components based on the result of an image of the color pattern by a CCD camera, and the illuminance and chromaticity properties of the corresponding color LED groups are calculated.

[0008] Furthermore, JP 2010 – 538 434 A (WO 2009 / 034 060 A1) specifies a technique for adjusting the color, color temperature, or chromaticity coordinates of mixed light emitted by an LED spotlight, with which the color, color temperature, or chromaticity coordinates of the mixed light can be kept constant. Additionally, JP 2014 - 134 527 A specifies a technique for calibrating a variation (machine difference) in a measurement result caused by the type of LED measuring instrument used for testing an LED.

[0009] For example, if a full-color LED device is used as a light source, the device itself exhibits a very large individual variation in its light emission characteristics. Therefore, if the full-color LED device is used as a light source in a lighting fixture for illuminating a cabin, it may not be possible to achieve the desired chromaticity as estimated in the design.

[0010] Furthermore, an LED light source has a low luminous efficacy compared to a conventional light source. Therefore, it is difficult to install numerous LED light sources in various locations within a cabin and operate them simultaneously to illuminate the entire cabin. Because there is significant variation in luminous efficacy due to individual differences between LED devices, the perceived color temperature can differ between users at various locations within the cabin.

[0011] It is therefore necessary to suppress variations in the color tone of the lighting at different positions or to configure the lighting in such a way as to obtain illumination with a desired chromaticity. Accordingly, special, pre-selected LED fixtures must be used to minimize individual differences between the LED fixtures during actual use. Furthermore, only these special LED fixtures, selected according to predetermined criteria, may be used. This significantly increases the component costs for each LED fixture compared to a standard LED fixture. SUMMARY OF THE INVENTION

[0012] The invention was developed taking into account the circumstances mentioned above. It is an object of the invention to provide a lighting control device in which the light source to be used is not limited to a previously selected specific LED device, yet a lighting effect with a desired chromaticity can still be easily obtained.

[0013] This is achieved by a lighting control device with the features of the patent claim.

[0014] Even if the light source in the lighting control device according to the present invention exhibits a large variation in light emission characteristics, or if the light emission characteristics have changed due to deterioration over time, etc., the correction coefficient entered into the control unit can be calibrated so that illumination with a desired chromaticity can be obtained. Accordingly, it is not necessary to use a previously selected special device as the light source, thereby reducing the cost of the lighting device.

[0015] In the lighting control device according to the present invention, the upstream control element calculates a difference between the actual chromaticity measured by the predetermined chromaticity measuring instrument and the predetermined chromaticity. Accordingly, the light source can be controlled based on this difference, thereby approximating the chromaticity of the emitted light to the predetermined chromaticity.

[0016] In the lighting control device according to the present invention, the light source is controlled to the predetermined reference light emission state when the chromaticity measuring instrument measures the chromaticity. Accordingly, a difference between the target chromaticity and the chromaticity in the actual light emission state can be easily detected. And if a plurality of light sources are present, the light sources emit according to their respective different light emission patterns. Therefore, based on the type of each light emission pattern, it can be identified which of the light sources produced a measurement result of the chromaticity measured by the chromaticity measuring instrument. Thus, it is easy to specify individual differences between the light sources.

[0017] In the lighting control device according to the invention, the light source to be used is not limited to a previously selected specific LED device, and yet an illumination with a desired chromaticity can still be easily obtained. Thus, even if the light source exhibits a large variation in its light emission properties, or if the light emission properties have changed due to deterioration over time, the correction coefficient entered at the control unit can be calibrated to obtain an illumination with the desired chromaticity.

[0018] The invention has been briefly described above. Details of the invention are clarified by the embodiments of the invention described below with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS Fig. Figure 1 is a block diagram showing a configuration example (1) of a calibration system for a vehicle with a lighting control device according to an embodiment of the invention. Fig. Figure 2 is an electrical circuit diagram showing a specific connection example for connecting a slave ECU to an LED device. Fig. Figure 3 is a flowchart showing an operating procedure of an entire calibration system in which an external facility is used. Fig. Figure 4 is a block diagram showing a configuration example for a cabin lighting system installed in a vehicle. Fig. Figure 5 is a schematic view showing a specific example of a variety of predetermined light emission patterns. Fig. Figure 6 is a block diagram showing a configuration example (2) of a calibration system for a vehicle with a lighting control device according to an embodiment of the invention. Fig. Figure 7 is a flowchart showing the operation of the entire calibration system, in which control is performed only by a system integrated into the vehicle. Fig. Figure 8 is a schematic view showing specific examples of an environment in which color correction of colored lighting is performed. DETAILED DESCRIPTION OF EXAMPLE FORMS OF EXECUTION

[0019] Specific embodiments of the invention are described below with reference to the drawings. (First embodiment)<Konfigurationsbeispiel eines Systems>

[0020] A configuration example (1) of a calibration system 100 for a vehicle with a lighting control device according to an embodiment of the invention is shown in Fig. 1 shown. The calibration system 100 of Fig. 1 comprises a lighting control device 10, an external device 30, LED devices 21 to 24 and chromaticity sensors 31 to 34.

[0021] The LED devices 21 to 24 each serve as light sources for illuminating a cabin of the vehicle. Specifically, each of the LED devices 21 to 24 uses a full-color LED containing three LED elements, each emitting light with red (R), green (G), and blue (B) wavelengths. These LED devices 21 to 24 are arranged at different positions within the cabin, allowing different areas to be illuminated by the LED devices 21 to 24 with corresponding amounts of light and corresponding chromaticities.

[0022] The lighting control device 10 is a device for controlling the lighting provided by the LED devices 21 to 24. The lighting control device 10 is equipped with a master ECU 11 and a slave ECU 12 (ECU stands for Electronic Control Unit and is therefore an electronic control unit). The master ECU 11, the slave ECU 12, and the LED devices 21 to 24 are connected to each other via a wiring harness WH.

[0023] An upstream end of the wiring harness WH is connected to the master ECU 11. An electronic circuit of the slave ECU 12 is integrated into a connector EC, which is provided on the upstream end of the wiring harness WH. A downstream end of the slave ECU 12 is connected to the LED devices 21 and 22 via a predetermined sub-wiring harness.

[0024] In the configuration of Fig. 1 Two LED devices 21 and 22 are connected under the slave ECU 12 and the other two LED devices 23 and 24 are connected under the master ECU 11.

[0025] The WH wiring harness contains a power supply line for connecting to a power source, a grounding line, and a communication line. The communication line enables data communication between the master ECU 11 and the slave ECU 12. Through this data communication, the master ECU 11 can transmit commands or various information to the slave ECU 12, or receive various information from the slave ECU 12.

[0026] In the configuration of Fig. Only one slave ECU 12 is used, however, two or more independent slave ECUs 12 can also be connected under the master ECU 11 via the wiring harness WH. Thus, even if a large number of LED devices distributed at various locations, such as in a vehicle, need to be controlled, the multiple slave ECUs 12 can be used to control these LED devices in accordance with a command from the master ECU 11. Furthermore, the electronic circuitry of the slave ECU 12 in the connector EC on the downstream side of the wiring harness is configured as follows: Fig. 1. However, the Slave-ECU 12 can also be arranged in various devices fixed inside the vehicle.

[0027] The external device 30 is an independent electronic device, separate from the vehicle's integrated system. The external device 30 is connected to the lighting control device via an external device connector 13 only when calibrating the LED devices 21 to 24 is being performed. After calibration is complete, the external device 30 can be disconnected from the external device connector 13, thus separating it from the vehicle's integrated system.

[0028] In the same way as various other electronic control units for use in a vehicle, the external device 30 can be formed by hardware of an electronic circuit, consisting mainly of a control microcomputer, and by software for implementing the functions of the external device 30.

[0029] The multiple chromaticity sensors 31 to 34 can be connected to a body of the external device 30 via a connecting cable 35. When the LED devices 21 to 24 are calibrated, as described in Fig. Figure 1 shows the chromaticity sensor 31 arranged in the vicinity of the LED device 21, the chromaticity sensor 32 arranged in the vicinity of the LED device 22, the chromaticity sensor 33 arranged in the vicinity of the LED device 23, and the chromaticity sensor 34 arranged in the vicinity of the LED device 24.

[0030] The external device 30 has a function for individually calculating corresponding correction coefficients for calibrating the chromaticities of the illumination lights of the LED devices 21 to 24, based on differences between the chromaticities measured by the chromaticity sensors 31 to 24 and previously determined reference chromaticities. Furthermore, the external device 30 can transmit data of the calculated correction coefficients to the master ECU 11 and the slave ECU 12.

[0031] Master ECU 11 takes into account the correction coefficients received from external device 30 when controlling LED devices 23 and 24 and adjusts the power line operating cycles accordingly, so that the appropriate chromaticity is maintained in the illumination of LED devices 23 and 24. Slave ECU 12 also takes into account the correction coefficients received from external device 30 when controlling LED devices 21 and 22 and adjusts the power line operating cycles accordingly, so that the appropriate chromaticity is maintained in the illumination of LED devices 21 and 22. The correction coefficients to be entered into Slave ECU 12 can be received directly from external device 30 or via Master ECU 11. <Detaillierte Beschreibung einer Konfiguration>

[0032] A specific connection example for connecting the slave ECU 12 to the LED device 21 is shown in Fig. 2 shown. As in Fig. As shown in Figure 2, the LED device 21 contains three LED elements, each emitting light with red (R), green (G), and blue (B) wavelengths. The anodes (positive electrodes) of the three LED elements are connected to a single conductor of the sub-wiring harness 25, which is shared by all anodes (positive electrodes). The cathodes (negative electrodes) of the three LED elements are each individually connected to three conductors of the sub-wiring harness 25. The other LED devices 22 to 24 are connected in the same manner.

[0033] A connector 25a on an upstream side of the sub-cable harness 25 is connected to an output side of the slave ECU 12. A control circuit 12a and an LED driver 12b are provided in the slave ECU 12.

[0034] Three switching elements (e.g., transistors) and three resistors are provided to individually switch the three LED elements in the LED device 21. A predetermined DC voltage Vb is supplied by the slave ECU 12 to the anode sides of the three LED elements in the LED device 21 via the sub-wiring harness 25.

[0035] The control circuit 12a can supply a control signal to each of the control input terminals (bases) of the three switching elements in the LED driver 12b, thereby controlling the switching element individually ON / OFF. If the control signal is switched periodically and pulse-wise to adjust the operating cycle between an ON section and an OFF section, the average value of the current flowing into each of the LED elements can be controlled. In this way, the light output of the corresponding red, green, and blue-colored lights can be adjusted. Furthermore, a light with different chromaticities can be obtained by combining the red, green, and blue light outputs.

[0036] Incidentally, the full-color LED device generally exhibits a large individual difference in its light emission characteristics. Therefore, even if the R, G, and B ratios are fixed during the operating cycle for the three LED elements in the LED device 21, a large variation occurs in the chromaticity of the resulting illumination. To correct this variation, the slave ECU 12 uses a correction coefficient calculated by the external device 30. The control circuit 12A takes the correction coefficient into account during the operating cycle of the control signal supplied to the LED driver 12b. <Betrieb bei der Durchführung einer Kalibrierung der Beleuchtungschromatizität>

[0037] An operating procedure for the entire calibration system 100 with the use of the external device 30 of Fig. 1 is in Fig. 3 shown.

[0038] It can be assumed that the illumination chromaticity calibration work is carried out before delivery, for example in a vehicle manufacturing plant, when devices with large individual differences in light emission characteristics are used, such as the LED devices 21 to 24 of Fig. 1. Or it can be assumed that the illumination chromaticity calibration work, taking into account the influence of deterioration over time, etc., is carried out after delivery of the vehicle by a vehicle dealer who performs maintenance on the vehicle to maintain its quality. In both cases, a worker performs the work using the external device 30, so that the operation of Fig. 3 can be carried out.

[0039] To perform the calibration work, the worker prepares the external device 30 and connects the external device 30 to the external device connection part 13 of the lighting control device 10. Furthermore, the worker arranges the chromaticity sensors 31 to 34 in the vicinity of the LED devices 21 to 24 on the vehicle in a state in which the chromaticity sensors 31 to 34 are connected to the body of the external device 30 via the connecting cable 35, so that a chromaticity measurement can be carried out (S21).

[0040] When the external device 30 is started, it performs an individual chromaticity measurement on the LED devices 21 to 24 using the chromaticity sensors 31 to 34 during the light emission of the LED devices 21 to 24 (S22). As explained below, the LED devices 21 to 24 emit light according to predetermined light emission patterns, each of which is different. Accordingly, the external device 30 can perform information on chromaticities measured by the chromaticity sensors 31 to 34 in a state in which the information on the measured chromaticities has been associated with the LED devices 21 to 24 based on the identification of the light emission patterns.

[0041] The external tool 30 calculates correction coefficients for LED devices 21 to 24, each based on the results of the chromaticity measurement (S23) obtained in step S21. For example, differences between measured values ​​of the corresponding R, G, and B color components, obtained when LED device 21 emits white light, and reference values ​​of the R, G, and B color components are combined to form a correction coefficient. If, for example, two bits are assigned to each of the R, G, and B color components, the correction coefficient for an LED device can be expressed by 6 bits (2 × 3).

[0042] The external device 30 transmits data of the correction coefficients calculated in step S23 to the master ECU 11 and the slave ECU 12 (S24). By taking the identification results of the light emission patterns into account, a suitable correspondence between the correction coefficients and the LED devices 21 to 24 can be obtained. For example, the external device 30 transmits correction coefficient data in a sequence depending on the types of light emission patterns, or it transmits correction coefficient data with added identification information corresponding to the types of light emission patterns.

[0043] In contrast, the master ECU 11 or the slave ECU 12 identifies whether a calibration mode has been designated or not (S11). If the mode is changed to calibration mode, the master ECU 11 or the slave ECU 12 proceeds to step S12. For example, if it is detected that the external device 30 has been connected to the external device connection part 13, or if a predetermined switching operation by a user is detected, the master ECU 11 changes the mode to calibration mode. Once the master ECU 11 changes the mode to calibration mode, it issues a command to the slave ECU 12 to change the mode to calibration mode.

[0044] The master ECU 11 or the slave ECU 12 determines a light emission pattern in calibration mode for each of the LED devices (21 to 24) connected to the master ECU 11 or the slave ECU 12 (S12). The light emission pattern is selected from a variety of pre-defined light emission patterns (described below), allowing each of the LED devices (21 to 24) to be assigned a different light emission pattern. Therefore, the LED devices 21 to 24 can be distinguished from one another based on differences in their light emission patterns.

[0045] The master ECU 11 or the slave ECU 12 assigns a predetermined calibration reference value (constant) to each of the colors R, G, B and W (white) for a power line operating cycle, with which each of the LED devices (21 to 24) connected under the master ECU 11 or the slave ECU 12 can be operated in calibration mode (S13).

[0046] The master ECU 11 or the slave ECU 12 controls an electrical connection state of each of the LED devices (21 to 24) connected under the master ECU 11 or the slave ECU (12) based on the power line operating cycle assigned in step S13 and the light emission pattern determined in step S12. Accordingly, the LED devices 21 to 24 emit red, green, blue, or white colored light.

[0047] Once the chromaticity measurement is complete, the operations of the master ECU 11 and the slave ECU 12 proceed from step S15 to step S16. For example, if a fixed time has elapsed since switching to calibration mode and a predetermined input operation has been detected by the user, or if a predetermined termination signal is input from the external device 30, this is recognized by the master ECU 11 and the slave ECU 12 as the completion of the chromaticity measurement.

[0048] The master ECU 11 or the slave ECU 12 accepts the input of the correction coefficients sent by the external device 30 in calibration mode (S16). The correction coefficients for the LED devices 21 to 24, acquired by the master ECU 11 and the slave ECU 12, are updated to reflect the information last entered in step S16. The correction coefficients are written to a non-volatile memory (not shown) provided on the master ECU 11 or the slave ECU 12 (S17). <Konfigurationsbeispiel eines praktikableren Kabinenbeleuchtungssystems>

[0049] A configuration example of a cabin lighting system installed in a vehicle is shown in Fig. 4 shown.

[0050] In the cabin lighting system of Fig. 4. A large number of LED fixtures 50 to 59 for lighting are arranged such that they are distributed at various positions in the cabin. These LED fixtures 50 to 59 are connected to a master ECU 11 via a wiring harness WH. Connectors (EC) are each connected to the downstream end sections of the wiring harness WH, and slave ECUs 12 are provided internally within the connectors. The LED fixtures 50 to 59 are located below the slave ECUs 12, adjacent to the LED fixtures 50 to 59.

[0051] Because a communication line is included in the WH wiring harness, data communication can be carried out between the master ECU 11 and each of the slave ECUs 12. Accordingly, the function of the calibration system 100 can be... Fig. 1 also directly on the in Fig. The cabin lighting system shown in section 4 can be used. <Spezifisches Beispiel für Lichtemissionsmuster>

[0052] A specific example of predetermined light emission patterns is in Fig. 5 shown.

[0053] In the example of Fig. Each of the ten types of light emission patterns is formed by a combination of R-colored, G-colored, B-colored, and W-colored light emission. However, the length of the delay time between the emission of the B-colored light and the emission of the W-colored light differs for the various light emission patterns.

[0054] For example, if a calibration control of the cabin lighting system from Fig. 4. The ten types of light emission patterns can be determined by Fig. 5 each are assigned to the ten LED devices 50 to 59.

[0055] The external facility 30 of Fig. 1. Differences can be made between the lengths of the delay times of Fig. 5. The light emission states of the LED devices are distinguished when the chromaticity sensors (31 to 34) measure them. Accordingly, the external device 30 can identify the light emission patterns so that the LED devices 50 and 59 can be distinguished from each other as targets to be measured. (Second embodiment)<Konfigurationsbeispiel des Systems>

[0056] A configuration example (2) of a calibration system 100B for a vehicle, which includes a lighting control device according to an embodiment of the invention, is shown in Fig. Figure 6 shows the 100B calibration system from Fig. 6 includes a lighting control device 10B, a measuring ECU 40 and LED devices 21 to 24.

[0057] The measuring ECU 40 is an electronic control unit integrated into a measuring unit and functions as an instrument panel in the vehicle. In this embodiment, the ECU 40 accepts user input for performing calibration work on the lighting control device 10B. If a modification is made so that the master ECU 11 in the lighting control device 10B can control the measuring ECU 40, the use of the measuring ECU 40 can be dispensed with.

[0058] In the same way as in the first embodiment, each of the LED devices 21 to 24 is Fig. 6. A light source for illuminating a vehicle cabin. In particular, each of the LED devices 21 to 24 uses a full-color LED containing three LED elements for emitting light with wavelengths R (red), G (green), and B (blue). These LED devices 21 to 24 are arranged at different positions in the cabin so that different positions in the cabin can be illuminated by the LED devices 21 to 24 with corresponding amounts of light and corresponding chromaticities.

[0059] The lighting control device 10B is a device for controlling the lighting provided by the LED devices 21 to 24. The lighting control device 10B comprises a master ECU 11 and a slave ECU 12 (ECU stands for Electronic Control Unit). The master ECU 11, the slave ECU 12, and the LED devices 21 to 24 are interconnected via a wiring harness WH.

[0060] An upstream end of the wiring harness WH is connected to the master ECU 11. An electronic circuit of the slave ECU 12 is internally integrated in a connector EC, which is provided on the upstream end of the wiring harness WH. A downstream end of the slave ECU 12 and each of the LED devices 21 and 22 are connected to each other via a predetermined sub-wiring harness.

[0061] In the configuration of Fig. 6 Two LED devices 21 and 22 are connected under the slave ECU 12 and the other two LED devices 23 and 24 are connected under the master ECU 11.

[0062] The WH wiring harness includes a power supply line for connecting to a power source, a grounding line, and a communication line. The communication line enables data communication between the master ECU 11 and the slave ECU 12. Through this data communication, the master ECU 11 can transmit commands or various information to the slave ECU 12, or receive various information from the slave ECU 12.

[0063] The master ECU 11 of the lighting control device 10B is connected to the measuring ECU 40 via a measuring connection part 13B. For practical purposes, it can be assumed that the lighting control device 10B is connected to the measuring ECU 40 via a communication network (e.g., CAN: Controller Area Network) inside the vehicle.

[0064] If in the calibration system 100B of Fig. 6. When a lighting calibration is performed, the measuring ECU 40 accepts an input from a user to determine correction values. The measuring ECU 40 transmits the correction coefficients for the LED devices 21 to 24 to the master ECU 11. <Betrieb bei der Durchführung einer Kalibrierung der Beleuchtungschromatizität>

[0065] The operation of the entire calibration system, in which no external facility 30 as in Fig. 1 is used, but the control is only by a system integrated into the vehicle, such as in the calibration system 100B from Fig. 6 is carried out in Fig. 7 shown.

[0066] If devices with large individual differences in light emission properties than the LED devices 21 to 24 of Fig. When using 6, the chromaticity of the illumination received from each of the light sources (devices) can deviate significantly from the desired value. For example, considerable differences in the chromaticity of the multiple LED devices, which should simultaneously emit light of the same color, are possible, so that the color tone perceived by a user varies at different positions in the cabin, which the user perceives as a defect.

[0067] After accepting a user input from a user, the 100B calibration system performs Fig. 6. Perform a lighting calibration so that any difference (variation) in the chromaticity of the actual color of the light emission from the LED devices can be suppressed, or the chromaticity can be changed to a chromaticity preferred by the user. When such calibration work is performed, the operation of Fig. 7 carried out.

[0068] The measuring ECU 40 monitors the presence / absence of a user input on a predetermined switch to identify whether a command to change the mode to a "lighting calibration mode" has been issued (S41). If the command to change the mode has been issued, the measuring ECU 40 proceeds to step S42. The measuring ECU 40 transmits a command to start the calibration mode to the master ECU 1 of the lighting control unit 10B (S42).

[0069] The measuring ECU 40 uses a display screen of a display provided on a measuring unit, or a display of a device integrated into a vehicle such as a navigation device, to provide a user interface for user input and accepts the user input (S43).

[0070] For example, the measuring ECU 40 can detect user input for calibration purposes by monitoring various switching states on or near the vehicle's steering wheel. And if a touch panel is provided on the display screen, input can be detected via the touch panel.

[0071] The measuring ECU 40 performs various processes according to the detected user input (S44). For example, the measuring ECU 40 performs the following processes: selecting an LED device as a target to be calibrated; selecting a light emission color (R, G, B, W) during calibration; correcting (increasing / decreasing) a correction coefficient; transmitting the corrected correction coefficient to the master ECU 11; etc. The measuring ECU 40 repeats the processes until it detects a predetermined calibration completion command (S43 to S45).

[0072] In contrast, the master ECU 11 in the lighting control device 10B switches from normal operating mode to calibration mode in accordance with a command from the measuring ECU 40 and proceeds from step S31 to step S32. Each of the power line operating cycles of the LED devices 23 and 24 connected to the master ECU 11 and the LED devices 21 and 22 connected to the slave ECU 12 is set to its calibration reference value. If a correction coefficient has already been held, the master ECU 11 changes the calibration reference value to one that takes the value of the correction coefficient into account (S32).

[0073] The master ECU 11 and the slave ECU 12, which is located below the master ECU 11, operate the LED devices (21 to 24) using designated light emission patterns and the power line operating cycles specified in S32 in accordance with a command from the master ECU 40, which is issued in response to an input action by the user.

[0074] Regarding, for example, the user-specified R, G, B or W-colored light emission, the chromaticity of each of the operated LED devices (21 to 24) can be adjusted by the user, who visually checks the chromaticity of the operated LED device.

[0075] After receiving a corrected new correction coefficient from the measuring ECU 40, the ECU 11 takes the corrected correction coefficient into account to change the current-line operating cycle of the LED device (21 to 24) (S34 to S35). The master ECU 11 also periodically transmits the latest correction coefficient to the slave ECU 12.

[0076] Incidentally, the correction coefficient transmitted by the measuring ECU 40 contains an R color component, a G color component, and a B color component. If each of the R, G, and B color components is expressed by 2-bit information, the correction coefficient contains 6-bit information (2 × 3) corresponding to each of the LED devices.

[0077] While the calibration mode is in progress, the master ECU 11 repeatedly executes the processes of steps S33 to S36. When a command to complete the calibration mode is issued by the measurement ECU 40, the master ECU 11 proceeds from step S36 to step S37, in which the finally determined correction coefficient of the LED device is written to an internal non-volatile memory. <Spezifische Beispiele einer Umgebung, in der eine Farbkorrektur einer farbigen Beleuchtung durchgeführt wird>

[0078] Specific examples of an environment in which color correction of colored lighting is performed are in Fig. 8 shown. Regarding the environment in which color correction of colored lighting is carried out on each of the lighting devices in a vehicle, the color correction can be performed as shown in Fig. 8 shown, which can be carried out before or after delivery of the vehicle.

[0079] If color correction is carried out in a factory before delivery of the vehicle, the external facility can be 30 of Fig. 1. Accordingly, a correction coefficient for each of the LED devices can be determined using the device of the "first embodiment" described above, allowing calibration to be performed. Thus, even if there is a large variation in the light emission characteristics between the LED devices to be used, the LED devices can be controlled to obtain illuminating lights with chromaticities estimated during the design, and any unevenness in chromaticity between different positions can be suppressed. It is therefore not necessary to specifically select the LED devices to be used, which reduces the component costs for the LED devices.

[0080] Even if color correction was performed at the factory before the vehicle was delivered, color correction of the lighting may be necessary again due to the effects of deterioration over time, etc. It can therefore be assumed that color correction is carried out when a vehicle dealer performs maintenance on the vehicle after delivery. On this occasion, the external facility 30 of Fig.1. Accordingly, a correction coefficient can be determined for each of the LED devices using the device of the "first embodiment" described above, so that calibration can be performed. Thus, even if the light emission characteristics of the LED devices used have changed due to the influence of deterioration over time, etc., the LED devices can be controlled to obtain illumination with chromaticities estimated during the design, and any unevenness in chromaticity at the different positions can be suppressed.

[0081] Even if color correction was performed at the factory before delivery of the vehicle, further color correction of the lighting may be necessary due to deterioration over time, or because the user does not like the color tone. The user can perform the color correction themselves. However, in this case, the user cannot use the external device 30. Therefore, the user performs the calibration only using the system integrated into the vehicle, as with the device of the "second embodiment" described above. Through calibration, changes in the chromaticity of each of the LED devices due to deterioration over time or variations in color tone at different positions can be suppressed, or the color tone can be adjusted according to the user's preferences.

[0082] The features of the embodiments of the lighting control device according to the invention, as described above, are briefly summarized below under points [1] to [7]. [1] Lighting control device (10) comprising: a control unit (master ECU 11) that controls the light emission states of luminaires with different light emission colors in such a way that a cabin is illuminated by emitted light emitted by a light source (LED device 21 to 24) and having a predetermined chromaticity, wherein the light source comprises the luminaires, the control unit controls the light emission states of the luminaires according to an externally entered correction coefficient in order to adjust the chromaticity of the emitted light (S16, S17, S34, S37). [2] Lighting control device as described in point [1], further comprising: an input part (S43) that assumes a setting of the chromaticity of the emitted light, and a prior control unit (measuring ECU 40) which outputs the correction coefficient to the control unit in accordance with the information entered at the input unit (S44). [3] Lighting control device as described in point [1], further comprising: an upstream control unit (external device 30) which receives a signal expressing the chromaticity measured by a chromaticity measuring instrument (chromaticity sensor 31 to 34) for measuring the chromaticity of the emitted light, calculates the correction coefficient corresponding to a difference between the predetermined chromaticity and the measured chromaticity (S22, S23) and transmits the calculated correction coefficient to the control unit (S24). [4] Lighting control device as described in point [3], which further comprises: a connecting part (External-device-connecting part 13) that detachably connects the chromaticity measuring instrument. [5] Lighting control device according to one of points [1] to [4], wherein the correction coefficient is a correction coefficient for correcting one operating cycle for each of the luminaires. [6] Lighting control device according to point [3], wherein the control part has a calibration mode to be executed when the chromaticity measuring instrument measures the chromaticity, and wherein the control part controls the light source to a predetermined reference light emission state in the calibration mode. [7] Lighting control device according to point [6], wherein, if a plurality of light sources are available as targets to be controlled, the control element controls the plurality of light sources in accordance with a plurality of different light emission patterns in the calibration mode (S12, S14). Incidentally, the invention is not limited to the embodiments described above and various modifications, improvements, etc. to the embodiments described herein may be made within the scope of the patent claim.

Claims

[1] Lighting control device comprising: a control unit (11, 12) that controls the light emission states of luminaires, each with different light emission colors, such that a cabin is illuminated by emitted light emitted by a plurality of light sources (21, 22, 23, 24) and having a predetermined chromaticity, wherein each of the light sources (21, 22, 23, 24) has the luminaires, wherein the control unit (11, 12) controls the light emission states of the luminaires according to an externally input correction coefficient in order to adjust the chromaticity of the emitted light, and a prior control unit (11, 40) which, for each of the plurality of light sources (21, 22, 23, 24), receives a signal expressing the chromaticity measured by a chromaticity measuring instrument arranged in the vicinity of the respective light source (21, 22, 23, 24) for measuring the chromaticity of the emitted light, calculates the correction coefficient for each of the plurality of light sources (21, 22, 23, 24) in accordance with a difference between the predetermined chromaticity and the measured chromaticity and transmits the calculated correction coefficients to the control unit (11, 12), wherein the control unit has a calibration mode which is to be executed when the chromaticity measuring instruments measure the chromaticity, wherein the control unit (11, 12) controls the light sources (21, 22, 23, 24) to a predetermined reference light emission state in the calibration mode, and wherein the control unit (11, 12) controls the plurality of light sources (21, 22, 23, 24) each in accordance with a plurality of different light emission patterns in the calibration mode, wherein each of the plurality of light emission patterns consists of a combination of red light emissions, green light emissions, blue light emissions and white light emissions, and where the duration of the delay time between an emission of white light and an emission of blue, red, or green light differs from one light emission pattern to another.

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