Control device for vehicle lamp, computer program, and vehicle lamp

Abstract

A headlamp (4) is provided with a plurality of light sources (451), a sensor (452) for acquiring the temperature of the plurality of light sources (451), a light source control unit (453), and an ADB control unit (47). The ADB control unit (47) is provided with: an image generation unit (471) that outputs an image in which the lighting brightness of each of the plurality of light sources (451) is expressed as the brightness of a pixel corresponding to each of the light sources (451); and a storage unit (472) that stores a first image (I1) indicating a first brightness distribution of the lighting brightness and a second image (I2) indicating a second brightness distribution (D2) of the lighting brightness. The light source control unit (453) individually controls the lighting brightness of the plurality of light sources (451) on the basis of the image output from the image generation unit (471). When the measured temperature is higher than a first threshold value (TH1), an image generation unit (471) generates a composite image (Ic) based on the first image (I1) and the second image (I2) from the measured temperature, and outputs the composite image (Ic) to a light source control unit (453), i.e., starts derating control.

Description

Technical Field

[0001] The present disclosure relates to a control device for a vehicle lamp, a computer program, and a vehicle lamp. Background Art

[0002] As vehicle lamps, lamps having semiconductor light sources such as LEDs (light emitting diodes) or laser diodes are known. These semiconductor light sources have a function of reducing the amount of drive current supplied to the semiconductor light source so that the temperature of the semiconductor light source does not exceed the rated temperature, and suppressing a further rise in temperature, that is, a so-called derating function.

[0003] In addition, vehicle lamps that irradiate an ADB (Adaptive Driving Beam) light distribution pattern are also known. The ADB light distribution pattern is a light distribution pattern in which light is not irradiated to an area where there are objects such as oncoming vehicles or oncoming vehicles in the high beam light distribution pattern. By changing the non-irradiated area of the ADB light distribution pattern according to the presence or position of the object, glare to the object can be reduced.

[0004] Patent Document 1 discloses a vehicle lamp system that has a derating function and is configured to irradiate an ADB light distribution pattern. The vehicle lamp system of Patent Document 1 includes: a semiconductor light source; a controller that generates a light distribution command indicating a light distribution pattern; and a drive circuit that can perform derating control to reduce the amount of drive current supplied to the semiconductor light source based on the light distribution command and according to the state of the semiconductor light source.

[0005] Prior Art Documents

[0006] Patent Documents

[0007] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2016-185717 Summary of the Invention

[0008] Technical Problem to be Solved by the Invention

[0009] However, a high-precision ADB that controls the light distribution pattern with higher precision has been proposed. Such a high-precision ADB has, for example, a plurality of light sources arranged in a matrix. When performing derating control, it is complicated to calculate and set the amount of drive current set for each light source for such a plurality of light sources, and the calculation load of the device is large. In addition, it is also considered to calculate the distribution of the drive current corresponding to the temperature of the light source and store it in the storage unit in advance, but when storing the drive current distribution for each temperature in the storage unit, a large-capacity storage unit is required.

[0010] Therefore, an object of the present disclosure is to provide a control device for a vehicle lamp, a computer program, and a vehicle lamp having a plurality of light sources that can perform derating control with a small storage capacity.

[0011] Technical solution for solving technical problems

[0012] The control device of the present disclosure is a control device for a vehicle lamp. Among them, the vehicle lamp includes: a plurality of light sources arranged in a matrix; a temperature acquisition unit that acquires the temperature of at least a part of the plurality of light sources; a control unit that individually controls the lighting brightness of the plurality of light sources; the control device; the control device includes: an image generation unit that outputs an image representing the lighting brightness of each of the plurality of light sources arranged in a matrix as the brightness of pixels corresponding to each light source; a storage unit that stores a first image representing a first brightness distribution of the lighting brightness and a second image representing a second brightness distribution of the lighting brightness with an average brightness lower than the average brightness of the first image; the control unit individually controls the lighting brightness of the plurality of light sources based on the image output from the image generation unit. When the temperature acquired by the temperature acquisition unit is below a first threshold, the image generation unit outputs the first image to the control unit. When the temperature acquired by the temperature acquisition unit is higher than the first threshold, a composite image based on the first image and the second image is generated according to the temperature, and the composite image is output to the control unit, that is, the derating control is started.

[0013] The computer program of the present disclosure can be executed by a control device mounted on a vehicle lamp. Among them, the vehicle lamp includes: a plurality of light sources arranged in a matrix; a temperature acquisition unit that acquires the temperature of at least a part of the plurality of light sources; a control unit that individually controls the lighting brightness of the plurality of light sources; the control device; by executing the computer program, the control device outputs an image representing the lighting brightness of each of the plurality of light sources arranged in a matrix as the brightness of pixels corresponding to each light source, individually controls the lighting brightness of the plurality of light sources based on the output image, stores a first image representing a first brightness distribution of the lighting brightness and a second image representing a second brightness distribution of the lighting brightness with an average brightness lower than the average brightness of the first image. When the temperature acquired by the temperature acquisition unit is below a first threshold, the first image is output to the control unit. When the temperature acquired by the temperature acquisition unit is higher than the first threshold, a composite image based on the first image and the second image is generated according to the temperature, and the composite image is output to the control unit, that is, the derating control is started.

[0014] The vehicle lamp according to the present disclosure includes: a plurality of light sources arranged in a matrix; a temperature acquisition unit that acquires the temperature of at least a part of the plurality of light sources; an image generation unit that outputs an image representing the lighting brightness of each of the plurality of light sources arranged in a matrix as the brightness of pixels corresponding to the respective light sources; a control unit that individually controls the lighting brightness of the plurality of light sources based on the image output from the image generation unit; a storage unit that stores a first image representing a first brightness distribution of the lighting brightness and a second image representing a second brightness distribution of the lighting brightness with an average brightness lower than the average brightness of the first image; when the temperature acquired by the temperature acquisition unit is equal to or lower than a first threshold, the image generation unit outputs the first image to the control unit, and when the temperature acquired by the temperature acquisition unit is higher than the first threshold, the image generation unit generates a composite image based on the first image and the second image according to the temperature and outputs the composite image to the control unit, that is, starts the derating control.

[0015] Advantageous Effects of the Invention

[0016] According to the present disclosure, it is possible to provide a control device, a computer program, and a vehicle lamp for a vehicle having a plurality of light sources that can perform derating control with a relatively small storage capacity. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a module diagram of a vehicle system in a vehicle equipped with the vehicle lamp according to the present disclosure.

[0018] Figure 2 It is an example Figure 1 A schematic diagram of the structure of the high beam lamp included.

[0019] Figure 3 It is a schematic diagram of the ADB light distribution pattern of an example reference example.

[0020] Figure 4 It is a schematic diagram of the high-precision ADB light distribution pattern of an example of the present disclosure.

[0021] Figure 5 It is a schematic diagram of the first image of an example of the present disclosure.

[0022] Figure 6 It is a schematic diagram of the second image of an example of the present disclosure.

[0023] Figure 7 It is a schematic diagram of the composite image of an example of the present disclosure.

[0024] Figure 8 It is a flowchart of the derating function of an example of the present disclosure.

[0025] Figure 9 It is an exampleFigure 1 A graph showing the relationship between the average brightness and temperature of multiple light sources included in a vehicle lamp.

[0026] Figure 10 It is a module diagram of a first modification example of a vehicle system.

[0027] Figure 11 It is a flowchart showing derating control of an example second modification example.

[0028] Figure 12 It is a graph showing the diachronic changes in the temperature of multiple light sources and the diachronic changes in the drive current amount as an example of derating control of a second modification example. Detailed implementation manners

[0029] Hereinafter, embodiments of the present disclosure (hereinafter referred to as the present embodiments) will be described with reference to the drawings. For ease of explanation, the dimensions of each component shown in these drawings are sometimes different from the actual dimensions of each component.

[0030] Hereinafter, with reference to Figure 1 the vehicle system 2 in the vehicle 1 equipped with the headlamp 4 of the present embodiment will be described. Figure 1 It is a module diagram of the vehicle system 2.

[0031] As Figure 1 shown, the vehicle system 2 includes a vehicle control unit 3, a headlamp 4, and a camera 6.

[0032] The vehicle control unit 3 is configured to control the running of the vehicle 1. The vehicle control unit 3 is constituted by, for example, at least one electronic control unit (ECU: Electronic Control Unit). The electronic control unit includes a computer system (such as a SoC (System on a Chip)) including one or more processors and one or more memories, and an electronic circuit constituted by active elements such as transistors and passive elements. The processor includes, for example, at least one of a CPU (Central Processing Unit), an MPU (Micro Processing Unit), a GPU (Graphics Processing Unit), and a TPU (Tensor Processing Unit). The CPU may be constituted by multiple CPU cores. The GPU may be constituted by multiple GPU cores. The memory includes a ROM (Read Only Memory) and a RAM (Random Access Memory). The ROM may store a vehicle control program. For example, the vehicle control program may also include an artificial intelligence (AI) program for autonomous driving. The AI program is a program (learned mode) constructed by supervised machine learning or unsupervised machine learning (especially deep learning) using a multi-layer neural network. The vehicle control program, vehicle control data, and / or surrounding environment information indicating the surrounding environment of the vehicle may also be temporarily stored in the RAM. The processor may be configured to expand the program specified by various vehicle control programs stored in the ROM on the RAM and execute various processes through cooperation with the RAM. In addition, the computer system may be constituted by a non-Neumann type computer such as an ASIC (Application Specific Integrated Circuit) or an FPGA (Field-Programmable Gate Array). Further, the computer system may be constituted by a combination of a Neumann type computer and a non-Neumann type computer.

[0033] The camera 6 is, for example, a camera including an imaging element such as a CCD (Charge-Coupled Device) or a CMOS (Complementary Metal-Oxide-Semiconductor). The camera 6 is configured to output the image data representing the surrounding environment of the vehicle 1 to the vehicle control unit 3 on the basis of having acquired the image data. The vehicle control unit 3 acquires the surrounding environment information based on the transmitted image data. Here, the surrounding environment information may also include information related to an object existing outside the vehicle 1 (other vehicles including a preceding vehicle and an oncoming vehicle, pedestrians, signs, etc.). For example, the camera 6 detects a preceding vehicle traveling in front of the vehicle 1 and outputs the image data representing the preceding vehicle to the vehicle control unit 3. The vehicle control unit 3 acquires the surrounding environment information including information related to the preceding vehicle and information related to the distance or position of the preceding vehicle relative to the vehicle 1 based on the transmitted image data. The camera 6 may be configured as a single-lens reflex camera or a stereo camera.

[0034] The headlamps 4 are respectively arranged on the left and right sides of the front surface of the vehicle 1. The headlamp 4 includes a lamp control unit 41, a low beam lamp 43, a high beam lamp 45, and an ADB control unit 47. The headlamp 4 is an example of a vehicle lamp. The ADB control unit 47 is an example of a control device mounted on a vehicle lamp.

[0035] The lamp control unit 41 is configured to control the operation of the headlamp 4. In the present embodiment, the lamp control unit 41 is configured to control the low beam lamp 43 and control the high beam lamp 45 via the ADB control unit 47. The lamp control unit 41 is constituted by, for example, an electronic control unit (ECU). The electronic control unit includes a computer system (such as an SoC, etc.) including one or more processors and one or more memories and an electronic circuit constituted by active elements such as transistors and passive elements. The processor includes at least one of a CPU, an MPU, a GPU, and a TPU. The memory includes a ROM and a RAM. In addition, the computer system may be constituted by a non-Neumann type computer such as an ASIC or an FPGA.

[0036] In the present embodiment, the vehicle control unit 3 and the lamp control unit 41 are provided as separate structures, but the vehicle control unit 3 and the lamp control unit 41 may also be integrally constituted. In this regard, the vehicle control unit 3 and the lamp control unit 41 may also be constituted by a single electronic control unit. The light source control unit 453 of the high beam lamp 45 or the image generation unit 471 of the ADB control unit 47 to be described later may also be configured as a part of the lamp control unit 41.

[0037] The high beam lamp 45 is configured to irradiate a high beam light distribution pattern HP in front of the vehicle 1. The low beam lamp 43 is configured to irradiate a low beam light distribution pattern LP in front of the vehicle 1. The high beam lamp 45 and the low beam lamp 43 may be integrally provided in one housing or may be separately provided in different housings.

[0038] The high beam lamp 45 is configured to further form a high-definition ADB (Adaptive Driving Beam) light distribution pattern as a specific light distribution pattern. The ADB light distribution pattern refers to a light distribution pattern that does not irradiate light to an area in the high beam light distribution pattern where a preceding vehicle or an oncoming vehicle exists, and is a light distribution pattern that changes the non-irradiated area according to the presence or position of the preceding vehicle and the oncoming vehicle. The ADB light distribution pattern has the effect of not causing glare to occupants of the preceding vehicle or the oncoming vehicle. The high beam lamp 45 includes a plurality of light sources 451, at least one sensor 452, and a light source control unit 453. Refer to Figure 2 The structure of the high beam lamp 45 will be described. Figure 2 2 is a schematic diagram illustrating the structure of the high beam lamp 45 .

[0039] like Figure 2 As shown, the plurality of light sources 451 are supported by a light source control unit 453. The plurality of light sources 451 are arranged in a matrix. In other words, the plurality of light sources 451 are arranged two-dimensionally not only in one direction but also in another direction perpendicular to the one direction. In the present embodiment, the plurality of light sources 451 are, for example, micro LEDs.

[0040] At least one sensor 452 is configured to obtain the temperature of at least a portion of the multiple light sources 451. In the present embodiment, the high beam 45 has multiple sensors 452. Each sensor 452 is configured to output the temperature of at least one corresponding light source 451. Each sensor 452 is composed of, for example, a semiconductor temperature sensor (silicon diode) or the like. The multiple sensors 452 are built into the light source control unit 453. In this way, the multiple sensors 452 of the present embodiment are built into the light source control unit 453 that supports the multiple light sources 451, so that the temperatures of the multiple light sources 451 can be monitored more accurately. The sensor 452 is an example of a temperature acquisition unit.

[0041] At least one sensor 452 may output the temperature of, for example, a plurality of light sources 451 located at the center periphery among the plurality of light sources 451 arranged in a matrix. Thus, it is easy to grasp the temperature of the plurality of light sources 451 arranged in a matrix, especially the temperature of the light source 451 located at the center where the temperature tends to be high.

[0042] Alternatively, the plurality of light sources 451 arranged in a matrix may be divided into a plurality of sections, and each section may be provided with a sensor 452. One sensor 452 outputs the temperature of a corresponding section. In this case, the light source control unit 453 may be configured to input the average temperature of each section.

[0043] It should be noted that the multiple sensors 452 are not limited to directly measuring the temperatures of the multiple light sources 451 respectively. Additionally, the multiple sensors 452 are not limited to being built into the light source control unit 453. The multiple sensors 452 can be separated from the light source control unit 453, and the temperatures of the multiple light sources 451 can also be measured via other structures. For example, at least one sensor 452 can also measure the temperature of the substrate provided with the multiple light sources 451. Or, at least one sensor 452 can also measure the temperature of the heat sink provided with the multiple light sources 451.

[0044] The light source control unit 453 is configured to independently control the lighting brightness of the multiple light sources 451. More specifically, the light source control unit 453 independently controls the amount of drive current supplied from a current source (not shown) to each light source 451. Thereby, each light source 451 lights up with a brightness corresponding to the supplied amount of drive current. As a method for controlling the amount of drive current, it can also be a so-called DC dimming (analog dimming) that changes the value of the constant current supplied to each light source 451 or a so-called PWM dimming that is dimming based on pulse width modulation. It should be noted that in the present embodiment, lighting includes not only the case where each light source 451 lights up in a manner of switching from an extinguished state to a lit state with a specified brightness, but also the case of lighting while adjusting the brightness. The light source control unit 453 is constituted by, for example, an electronic control unit (ECU). The light source control unit 453 is supported on the substrate S via the electrode E. The light source control unit 453 is an example of a control unit.

[0045] The light source control unit 453 also has a so-called derating function, which is a function of reducing the amount of drive current supplied to the multiple light sources 451 so that the temperatures of the multiple light sources 451 do not exceed the rated temperature, thereby further suppressing the temperature rise. In the present embodiment, the light source control unit 453 exerts the derating function by independently controlling the lighting brightness of the multiple light sources 451 based on the image output from the image generation unit 471 described later. The details of the derating function will be described later.

[0046] Return Figure 1, continue with the description of the vehicle system 2. The ADB control unit 47 includes an image generation unit 471 and a storage unit 472. The storage unit 472 is configured to store an image in which the lighting brightness of each of the plurality of light sources 451 arranged in a matrix is represented as the brightness of a pixel corresponding to each light source 451. Further, the positions of the light sources 451 arranged in a matrix correspond to the positions of the pixels representing the brightness of the light sources 451. That is, the pattern of the brightness of the image stored in the storage unit 472 is consistent with the pattern of the brightness (or light distribution pattern) of the light sources 451. Further, the storage unit 472 stores two such images. Specifically, the storage unit 472 is configured to store a first image I1 representing a first brightness distribution D1 of the lighting brightness and a second image I2 representing a second brightness distribution D2 of the lighting brightness. The average brightness of the second image I2 is lower than the average brightness of the first image I1. Details of the first image I1 and the second image I2 will be described later.

[0047] The image generation unit 471 is configured to output an image in which the lighting brightness of each of the plurality of light sources 451 is represented as the brightness of a pixel corresponding to each light source 451. The image generation unit 471 is configured to generate a composite image Ic based on the first image I1 and the second image I2 according to the temperature of the plurality of light sources 451. The image generation unit 471 outputs the generated composite image Ic to the light source control unit 453 according to the temperature of the plurality of light sources 451. The image generation unit 471 is constituted by, for example, an electronic control unit (ECU). The operation of the image generation unit 471 will be described in detail later.

[0048] [High-precision ADB]

[0049] Next, refer to the following Figure 3 and Figure 4 to describe the high-precision ADB light distribution pattern of this embodiment.

[0050] Figure 3 is a schematic diagram of the ADB light distribution pattern of the example reference example. Figure 4 is a schematic diagram of the high-precision ADB light distribution pattern of this embodiment. In Figure 3 and Figure 4 the V-V line representing the vertical direction ( Figure 3 or Figure 4 the up-and-down direction in) at the center of the irradiation range of the ADB light distribution pattern, and the H-H line orthogonal to the V-V line and extending in the horizontal direction ( Figure 3 or Figure 4 the left-and-right direction in) are illustrated. Figure 3 and Figure 4 both represent the low beam light distribution pattern LP, but since any low beam light distribution pattern LP is the same, the description of the low beam light distribution pattern LP is omitted.

[0051] As Figure 3As shown, in the ADB light distribution pattern AZ of the reference example, the high beam light distribution pattern HZ is formed by being divided into a plurality of sub-light distribution patterns SZ. The plurality of sub-light distribution patterns SZ are arranged in one direction. In such an ADB light distribution pattern, for example, a plurality of light sources arranged in a line are provided, and by turning on and off one light source, light is irradiated or not irradiated to one sub-light distribution pattern SZ corresponding to the one light source.

[0052] In Figure 3 the example shown, the number of sub-light distribution patterns SZ is, for example, 12, and these sub-light distribution patterns SZ are arranged side by side in the horizontal direction. In Figure 3 it, in the horizontal direction, sub-light distribution patterns SZ1 to SZ12 are arranged side by side from the left.

[0053] For example, when there is a preceding vehicle X1 in front of the vehicle, the light source corresponding to the sub-light distribution pattern SZ6 is turned off so that light is not irradiated to the sub-light distribution pattern SZ6 corresponding to the position of the preceding vehicle X1. For example, when there is an oncoming vehicle X2 in front of the vehicle, the light sources corresponding to these sub-light distribution patterns SZ8 and SZ9 are turned off so that light is not irradiated to the sub-light distribution patterns SZ8 and SZ9 corresponding to the position of the oncoming vehicle X2. With such a structure, glare to the occupants of the preceding vehicle X1 or the oncoming vehicle X2 can be reduced.

[0054] In the ADB light distribution pattern AZ of the reference example, although the high beam light distribution pattern HZ is divided into a plurality of sub-light distribution patterns in the horizontal direction, it is not divided in the vertical direction. That is, one sub-light distribution pattern SZ occupies a relatively large range in the vertical direction. Therefore, for example, when there is a preceding vehicle X1 in the sub-light distribution pattern SZ6, light cannot be irradiated between the vehicle 1 and the preceding vehicle X1 and further ahead of the preceding vehicle X1.

[0055] On the other hand, as Figure 4 shown, in the high-precision ADB light distribution pattern AP, the high beam light distribution pattern HP is formed by being divided into a plurality of fine light distribution patterns MP. By turning on and off one light source 451, light is irradiated or not irradiated to one fine light distribution pattern MP corresponding to the one light source. Particularly in the present embodiment, a plurality of light sources 451 of the high beam lamp 45 are arranged in a matrix. Along with this, the fine light distribution patterns MP are also arranged in a matrix.

[0056] In this embodiment, 256 fine light distribution patterns MP are arranged in the horizontal direction and 64 are arranged in the vertical direction. In such a high-precision ADB light distribution pattern, the high beam light distribution pattern HP is divided into a plurality of fine light distribution patterns MP not only in the horizontal direction but also in the vertical direction. That is, the range occupied by one fine light distribution pattern MP is smaller than the range occupied by one sub-light distribution pattern SZ. Therefore, for example, when there is a preceding vehicle X1 in front of the vehicle, light is not irradiated only to the range MX1 of the fine light distribution pattern MP corresponding to the position of the preceding vehicle X1, and light can be irradiated between the own vehicle and the preceding vehicle X1 and further ahead of the preceding vehicle X1. Similarly, when there is an oncoming vehicle X2 or a pedestrian X3 in front of the vehicle, light is not irradiated only to the range MX2 of the fine light distribution pattern MP corresponding to the position of the oncoming vehicle X2 or to the range MX3 of the fine light distribution pattern MP corresponding to the face or upper body of the pedestrian X3, and light can be irradiated to other areas.

[0057] In this embodiment, high-precision means that fine light distribution patterns MP are arranged not only in the horizontal direction but also in the vertical direction, and 100 or more fine light distribution patterns MP are arranged in the horizontal direction.

[0058] As in this embodiment, in order to realize a high-precision ADB light distribution pattern, the light source control unit 453 needs to individually turn on and off a plurality of light sources 451 arranged in a matrix. Further, in order to perform derating control on the plurality of light sources 451 that form such a high-precision ADB light distribution pattern, it is necessary to adjust the lighting brightness of each light source 451, and the light source control unit 453 sometimes bears the corresponding processing load. Therefore, in this embodiment, by using an image in which the lighting brightness of each of the plurality of light sources 451 is represented as the brightness of a pixel corresponding to each light source 451, the processing load of the light source control unit 453 is reduced. Hereinafter, various images used in this embodiment will be described.

[0059] [First Image, Second Image, and Composite Image]

[0060] Refer to Figures 5 to 7 An image in which the lighting brightness of each of the plurality of light sources 451 arranged in a matrix is represented as the brightness of a pixel corresponding to each light source 451 will be described. Figure 5 It is a schematic diagram showing an example of the first image I1. Figure 6 It is a schematic diagram showing an example of the second image I2. Figure 7 It is a schematic diagram showing an example of the composite image Ic. Figures 5 to 7 The image is represented on the x-axis and y-axis as two-dimensional coordinate axes, and the brightness of the pixel at the coordinate position of each pixel is represented by F(x, y).

[0061] Figure 5The first image I1 shown is an image showing a case where the lighting brightness of the plurality of light sources 451 becomes the first brightness distribution D1. The first brightness distribution D1 is the brightest brightness distribution in which the plurality of light sources 451 can be lit as a whole. The average brightness of the first brightness distribution D1 shown in the first image I1 is the first average brightness L1. The first image I1 is an image used before the derating function of the light source control unit 453 operates (before the start of derating control). Further, the first image I1 is an image for generating the composite image Ic during the period when the derating function of the light source control unit 453 operates (during derating control).

[0062] Figure 6 The second image I2 shown is an image showing a case where the lighting brightness of the plurality of light sources 451 becomes the second brightness distribution D2. The second brightness distribution D2 is an image used when the derating function operates most strongly. That is, the second brightness distribution D2 is an image used when driving the plurality of light sources 451 in such a way that the heat generation from the plurality of light sources 451 is minimized while maintaining the obtained light distribution pattern. Therefore, the average brightness of the second brightness distribution D2 shown in the second image I2, that is, the second average brightness L2, is lower than the first average brightness L1 of the first image I1. In other words, compared with the case of the first image I1, the plurality of light sources 451 in the case of the second image I2 are lit in a way that is dimmer as a whole. The second image I2 is an image for generating the composite image Ic during the period when the derating function of the light source control unit 453 operates (during derating control).

[0063] Figure 7 The composite image Ic shown is an image generated by synthesizing the first image I1 and the second image I2 according to the temperature of the plurality of light sources 451. The composite image Ic is an image indicating that the lighting brightness of the plurality of light sources 451 becomes the composite brightness distribution Dc. The average brightness of the composite brightness distribution Dc shown in the composite image Ic, that is, the composite average brightness Lc, is higher than the second average brightness L2 of the second image I2 and lower than the first average brightness L1 of the first image I1. In other words, in the case of the composite image Ic, the plurality of light sources 451 are lit in a way that is dimmer as a whole compared with the case of the first image I1 and brighter as a whole compared with the case of the second image I2. The composite image Ic is an image generated during the period when the derating function of the light source control unit 453 operates (during derating control).

[0064] [Derating Control]

[0065] Next, refer to Figure 8 and Figure 9 to describe the derating control of this embodiment. Figure 8 is a flowchart illustrating the derating control of this embodiment. Figure 9 is a graph illustrating the relationship between the average brightness and temperature of the plurality of light sources 451. The light source control unit 453 periodically executes Figure 8The flowchart shown

[0066] As Figure 8 shown, the light source control unit 453 obtains the temperature T of the plurality of light sources 451 from the sensor 452 (STEP1). Next, the light source control unit 453 determines whether the obtained temperature T of the plurality of light sources 451 is below the first threshold value TH1 (STEP2).

[0067] When the temperature T is below the first threshold value TH1 (Yes in STEP2), it is not necessary to suppress the heat generation amount of the plurality of light sources 451. In this case, the light source control unit 453 retrieves the first image I1 from the storage unit 472 and operates the plurality of light sources 451 with the first luminance distribution D1 shown in the first image I1 (STEP3). After that, the light source control unit 453 ends the process.

[0068] When the temperature T is higher than the first threshold value TH1 (No in STEP2), it is necessary to suppress the heat generation amount of the plurality of light sources 451, and the derating control is started. After that, the light source control unit 453 determines whether the temperature T is below the second threshold value TH2 (STEP4).

[0069] When the temperature T is below the second threshold value TH2 (Yes in STEP4), the image generation unit 471 determines the synthesis ratio according to the temperature T (STEP5). Further, the image generation unit 471 retrieves the first image I1 and the second image I2 from the storage unit 472, and generates a composite image Ic according to the first image I1, the second image I2, and the synthesis ratio (STEP6).

[0070] In STEP6, the image generation unit 471 can generate the composite image Ic using, for example, the following formula (1). Note that in formula (1), the luminance of the pixel at (x, y) in the first image I1 is defined as F1(x, y)( Figure 5 ). The luminance of the pixel at (x, y) in the second image I2 is defined as F2(x, y)( Figure 6 ). The luminance of the pixel at (x, y) in the composite image Ic is defined as F3(x, y)( Figure 7 ). The synthesis coefficient α is set to the degree (first influence degree) to which the luminance F1(x, y) of the first image I1 may affect the luminance F3(x, y) of the composite image Ic, and is set to 0 < α < 1. The synthesis coefficient β is set to the degree (second influence degree) to which the luminance F2(x, y) of the second image I2 may affect the luminance F3(x, y) of the composite image Ic, and is set to 0 < β < 1.

[0071] F3(x, y) = α * F1(x, y) + β * F2(x, y) ··· (1)

[0072] Note that the above synthesis ratios are α and β in this example. In Equation (1), the synthesis coefficient α can also be a function of the temperatures of multiple light sources 451, α(T). Additionally, the synthesis coefficients α and β can also be set to satisfy the relationship α + β = 1. For example, the image generation unit 471 changes the first influence degree α(T) of the first image I1 in the synthesized image Ic according to the temperatures of multiple light sources 451. Specifically, when the temperature of multiple light sources 451 is higher than the first threshold TH1, the lower the temperature, the larger α(T). Conversely, when the temperature of multiple light sources 451 is higher than the first threshold TH1, the higher the temperature, the larger {1 - α(T)}. In STEP5, the image generation unit 471 determines the first influence degree α(T) as the synthesis ratio corresponding to the temperature T.

[0073] However, α and β can also be constants that do not change according to temperature. STEP5 only performs the process of reading in the constants.

[0074] Return Figure 8 , and continue the description of the flowchart.

[0075] As described above, the image generation unit 471 generates the synthesized image Ic. The light source control unit 453 operates multiple light sources 451 with the synthesized luminance distribution Dc shown in the generated synthesized image Ic (STEP7). In other words, when the temperature T obtained by the sensor 452 is greater than the first threshold TH1 and less than or equal to the second threshold TH2, the light source control unit 453 lights up multiple light sources 451 with the synthesized luminance distribution Dc shown in the synthesized image Ic. After that, the light source control unit 453 ends the process.

[0076] The synthesized average luminance Lc of the synthesized image Ic is lower than the first average luminance L1 of the first image I1. The heat generation amount of multiple light sources 451 when lighting up multiple light sources 451 based on the synthesized image Ic is reduced compared to the heat generation amount when lighting up multiple light sources 451 based on the first image I1. Therefore, it is possible to suppress the further increase in the temperature of multiple light sources 451.

[0077] On the other hand, when the temperature T of multiple light sources 451 is higher than the second threshold TH2 (STEP4 is "No"), the light source control unit 453 retrieves the second image I2 from the storage unit 472 and operates multiple light sources 451 with the second luminance distribution D2 shown in the second image I2 (STEP8). In other words, when the temperature measured by the sensor 452 is greater than the second threshold TH2, the light source control unit 453 lights up multiple light sources 451 with the second luminance distribution D2 shown in the second image I2. After that, the light source control unit 453 ends the process.

[0078] In the case of performing derating control on a plurality of light sources 451 arranged in a matrix, different from the above-described embodiment, it is complicated to calculate the drive current amounts supplied to the respective light sources 451 and set the luminance distribution corresponding to the drive current amounts. Such control sometimes increases the processing load on the light source control unit 453 or the image generation unit 471. Further, it is also possible to calculate in advance the distribution of the drive current amounts or the luminance distribution corresponding to the temperatures of the plurality of light sources 451 and store them in the storage unit 472. However, storing the distribution of the drive current amounts or the luminance distribution for each temperature in the storage unit 472 burdens the capacity of the storage unit 472.

[0079] According to the present embodiment, it is possible to set the luminance distribution at various temperatures by a simple method of synthesizing two images such as the first image I1 and the second image I2. Compared with the case of directly calculating the drive current amounts or the luminance of the respective light sources 451, the processing load can be significantly reduced. Further, the storage unit 472 only needs to store the two types of images, i.e., the first image I1 and the second image I2. Therefore, it is not necessary to prepare a storage unit with a large capacity.

[0080] [First Modification Example]

[0081] Next, a modification example of the vehicle system 2 will be described below with reference to Figure 10 FIG. Figure 10 is a block diagram of a vehicle system 2A according to the first modification example. In the Figure 10 structure shown, the same reference numerals are given to the same structures as those in the Figure 1 structure shown, and the description thereof is omitted.

[0082] As Figure 10 shown, the vehicle system 2A includes a vehicle control unit 3, a headlamp 4, and a camera 6.

[0083] In the Figure 1 embodiment shown, the high beam 45 includes a light source control unit 453, and the ADB control unit 47 includes an image generation unit 471. On the other hand, in the Figure 10 first modification example shown, the ADB control unit 47 includes a comprehensive control unit 473 instead of the light source control unit 453 and the image generation unit 471. The comprehensive control unit 473 is a single electronic control unit that integrates the functions of the light source control unit 453 and the functions of the image generation unit 471. The comprehensive control unit 473 is an example of a control unit. The derating control performed by the comprehensive control unit 473 is the same as the derating control performed by the light source control unit 453 and the image generation unit 471 ( Figure 8 ), and thus the description thereof is omitted.

[0084] As Figure 10As shown in the figure, the headlamp 4 of the first modification includes: a plurality of light sources 451 arranged in a matrix; a sensor 452 that acquires the temperature of at least a part of the plurality of light sources 451; an integrated control unit 473 that individually controls the lighting brightness of the plurality of light sources 451; and a storage unit 472 that stores an image representing the lighting brightness of each of the plurality of light sources 451 arranged in a matrix as the brightness of pixels corresponding to the respective light sources 451. The storage unit 472 stores a first image I1 representing a first brightness distribution D1 of the lighting brightness and a second image I2 representing a second brightness distribution D2 of the lighting brightness, the average brightness of which is lower than the average brightness shown in the first image I1. When the temperature T obtained by the sensor 452 is equal to or lower than the first threshold TH1, the integrated control unit 473 lights the plurality of light sources 451 with the first brightness distribution D1 shown in the first image I1. Further, when the temperature T obtained by the sensor 452 is higher than the first threshold TH1, the integrated control unit 473 generates a composite image Ic based on the first image I1 and the second image I2 according to the temperature T, and lights the plurality of light sources 451 with the brightness distribution shown in the composite image Ic.

[0085] In this modification, similarly to the above-described embodiment, by synthesizing two images such as the first image I1 and the second image I2, the processing load on the integrated control unit 473 can be significantly reduced. Further, since the storage unit 472 only needs to store the two types of images, the first image I1 and the second image I2, a large capacity is not required.

[0086] [Second Modification]

[0087] Next, a modification of the derating control will be described with reference to Figure 11 and Figure 12 A flowchart showing an example of the derating control of the second modification is shown in Figure 11 is a flowchart showing an example of the derating control of the second modification. Figure 11 is a process corresponding to STEP4 to STEP6 in the flowchart of Figure 8 When the temperature T is higher than the first threshold TH1 ( Figure 8 “No” in STEP2 of

[0088] ), although the derating control starts, there is a case where the temperature T of the plurality of light sources 451 does not immediately decrease. In the following second modification, as an example, the processing when the temperature T slowly rises after the derating control starts will be described. Figure 1 The other structure of the second modification is the same as the structure shown in

[0089] As shown in Figure 11As shown, after starting the derating control, the light source control unit 453 determines whether the temperature T acquired by the sensor 452 is higher than the third threshold value TH3 (STEP11).

[0090] When the temperature T is higher than the third threshold value TH3 (Yes in STEP11), in order to further suppress the heat generation amount of the plurality of light sources 451, the image generation unit 471 generates a composite image in such a manner that the temperature T decreases as follows. First, the image generation unit 471 retrieves a third image I3 as a reference image Iref described later from the storage unit 472 (STEP12). The third image I3 is an image whose average luminance is lower than the composite image I(t - 1) generated immediately before. The third image I3 is an image showing a state where the plurality of light sources 451 are lit dimly. The third image I3 may also be the second image I2.

[0091] After that, the image generation unit 471 generates the composite image I(t) generated at time t in such a manner that it becomes a composite image of the composite image I(t - 1) generated immediately before and the third image I3 (STEP13).

[0092] In STEP13, the image generation unit 471 generates a composite image using, for example, the following equation (2). In equation (2), the composite image I(t) is defined as a function generated at time t. The reference image Iref is an image referred to when generating the composite image I(t). The image generation unit 471 generates the composite image I(t) generated at time t as a composite image of the composite image I(t - 1) generated immediately before and the reference image Iref. The composite coefficient γ is set to the degree (third influence degree) to which the composite image I(t - 1) generated immediately before can affect the composite image I(t), and is set to 0 < γ < 1. The composite coefficient δ is set to the degree (fourth influence degree) to which the reference image Iref can affect the composite image I(t), and is set to 0 < δ < 1.

[0093] I(t) = γ * I(t - 1) + δ * Iref ··· (2)

[0094] The composite coefficients γ and δ may also be set to satisfy the relationship γ + δ = 1. For example, the image generation unit 471 changes the third influence degree γ of the reference image Iref in the composite image I(t) according to the temperature of the plurality of light sources 451. Specifically, when the temperature of the plurality of light sources 451 is higher than the third threshold value TH3, the lower the temperature, the larger γ. Conversely, when the temperature of the plurality of light sources 451 is higher than the third threshold value TH3, the higher the temperature, the larger {1 - γ}. In this way, the image generation unit 471 determines the third influence degree γ as a composite ratio according to the temperature T.

[0095] Return Figure 11, continue the description of the flowchart.

[0096] As described above, the image generation unit 471 generates the composite image I(t) (STEP13). The light source control unit 453 operates the plurality of light sources 451 with the composite luminance distribution shown in the generated composite image I(t) ( Figure 8 STEP7). After that, the light source control unit 453 ends the process.

[0097] The composite average luminance of the composite image I(t) is lower than the average luminance of the composite image I(t-1) generated immediately before. The heat generation amount of the plurality of light sources 451 when the plurality of light sources 451 are lit based on the composite image I(t) is reduced compared to the heat generation amount when the plurality of light sources 451 are lit based on the composite image I(t-1) generated immediately before. Therefore, it is possible to suppress a further increase in the temperature of the plurality of light sources 451.

[0098] On the other hand, when the temperature T of the plurality of light sources 451 is equal to or lower than the third threshold TH3 (in STEP11, "NO"), the light source control unit 453 determines whether the temperature T is lower than the fourth threshold TH4 (STEP14). The fourth threshold TH4 is a threshold lower than the third threshold TH3.

[0099] When the temperature T is lower than the fourth threshold TH4 (in STEP14, "YES"), the heat generation amount of the plurality of light sources 451 is suppressed more than necessary, the drive current amount supplied to the plurality of light sources 451 is too low, and the light distribution pattern becomes dark. Therefore, the image generation unit 471 increases the drive current amount supplied to the plurality of light sources 451 to brighten the light distribution pattern. That is, the image generation unit 471 generates a composite image I(t) that is brighter than the composite image I(t-1) generated immediately before. As a result, the image generation unit 471 generates a composite image in such a way that the temperature T rises. Specifically, first, the image generation unit 471 retrieves the fourth image I4 as the reference image Iref from the storage unit 472 (STEP15). The fourth image I4 is an image whose average luminance is higher than the composite image I(t-1) generated immediately before. The fourth image I4 is an image showing a state where the plurality of light sources 451 are lit brighter. The fourth image I4 may also be the first image I1.

[0100] After that, the image generation unit 471 generates the composite image I(t) generated at time t in such a way that it becomes a composite image of the composite image I(t-1) generated immediately before and the fourth image I4 (STEP13). The light source control unit 453 operates the plurality of light sources 451 with the composite luminance distribution shown in the generated composite image I(t) ( Figure 8 STEP7). After that, the light source control unit 453 ends the process.

[0101] The synthesized average brightness of the synthesized image I(t) is higher than the average brightness of the synthesized image I(t-1) generated immediately before. When the plurality of light sources 451 are lit based on the synthesized image I(t), the drive current amount of the plurality of light sources 451 increases as compared with the drive current amount when the plurality of light sources 451 are lit based on the synthesized image I(t-1) generated immediately before. Therefore, the plurality of light sources 451 are lit brighter.

[0102] On the other hand, when the temperature T of the plurality of light sources 451 is equal to or higher than the fourth threshold value TH4 and equal to or lower than the third threshold value TH3 (No in STEP14), it is considered that the heat generation amount of the light source 451 is balanced with the heat dissipation amount to the outside. Therefore, in this modified example, the drive current amount immediately before is maintained. Specifically, the image generation unit 471 sets the synthesized image I(t-1) generated immediately before as the reference image Iref (STEP16). Further, the image generation unit 471 generates the synthesized image I(t) such that the generated synthesized image I(t) becomes the synthesized image I(t-1) generated immediately before (STEP13). The light source control unit 453 operates the plurality of light sources 451 with the synthesized luminance distribution shown in the generated synthesized image I(t) ( Figure 8 STEP7). After that, the light source control unit 453 ends the process.

[0103] The above-described process is repeatedly executed at a predetermined time interval.

[0104] Figure 12 This is the derating control as the second modified example, and a graph showing the temporal change of the temperature T of the plurality of light sources 451 and the temporal change of the drive current amount after the derating control is started is shown. In Figure 12 , the horizontal axis represents time. The left vertical axis represents the temperature T acquired by the sensor 452, and the right vertical axis represents the drive current amount supplied to the plurality of light sources 451. The left vertical axis may also be the average temperature of the temperatures acquired by the plurality of sensors 452. The solid line represents the temporal change of the temperature T acquired by the sensor 452. The thick line represents the temporal change of the drive current amount supplied to the light source 451.

[0105] As Figure 12 shown, after the derating control is started, the drive current amount I0 is supplied to the light source 451. The drive current amount I0 is the drive current amount at the start of the derating control. The drive current amount I0 supplied to the light source 451 is maintained until the temperature T becomes higher than the third threshold value TH3. At this time, the temperature T rises slowly.

[0106] When the temperature T becomes higher than the third threshold TH3, in order to further suppress the heat generation amount of the plurality of light sources 451, the drive current amount supplied to the light source 451 is lower than the immediately preceding drive current amount. The higher the temperature T is above the third threshold TH3, the more significantly the drive current amount supplied to the light source 451 decreases compared to the immediately preceding drive current amount.

[0107] When the temperature T is lower than the fourth threshold TH4, in order to avoid the light distribution pattern from becoming darker than necessary, the drive current amount supplied to the light source 451 is higher than the immediately preceding drive current amount. The lower the temperature T is below the fourth threshold TH4, the more significantly the drive current amount supplied to the light source 451 increases compared to the immediately preceding drive current amount.

[0108] When the temperature T is equal to or higher than the fourth threshold TH4 and equal to or lower than the third threshold TH3, it is considered that the heat generation amount of the light source 451 and the heat dissipation amount to the outside are balanced. Therefore, the drive current amount supplied to the light source 451 is the same as the immediately preceding drive current amount. In other words, during the period when the temperature T is equal to or higher than the fourth threshold TH4 and equal to or lower than the third threshold TH3, the drive current amount supplied to the light source 451 is constant.

[0109] As described above, in this modification, after the derating control starts, when the temperature T acquired by the sensor 452 is higher than the third threshold TH3, the image generation unit 471 generates the composite image I(t) in such a way that the temperature T decreases. The composite image I(t) generated at time t is a composite image of the immediately preceding composite image I(t - 1) and the third image I3 whose average luminance is lower than that of the composite image I(t - 1). Therefore, it is possible to set the luminance distribution at various temperatures by a simple method of combining two images. Compared with the case of directly calculating the drive current amount or luminance of each light source 451, the processing load can be significantly reduced. Further, the storage unit 472 only needs to store the third image I3 and the fourth image I4. Therefore, there is no need to prepare a storage unit with a large capacity.

[0110] The third image I3 may also be the second image I2. In this case, the capacity of the storage unit 472 can be further reduced.

[0111] In this modification, after the derating control starts, when the temperature T acquired by the sensor 452 is lower than the fourth threshold, the image generation unit 471 generates the composite image I(t) in such a way as to obtain a bright light distribution pattern. As a result, the image generation unit 471 generates the composite image I(t) in such a way that the temperature T increases as a result. The composite image I(t) generated at time t is a composite image of the immediately preceding composite image I(t - 1) and the fourth image I4 whose average luminance is higher than that of the composite image I(t - 1). In such a case, the same effects as described above are also exhibited.

[0112] The fourth image I4 can also be the first image I1. In this case, the capacity of the storage unit 472 can be further reduced.

[0113] As described above, the embodiments and various modification examples of the present disclosure have been described. However, it goes without saying that the technical scope of the present disclosure should not be construed in a limiting manner by the descriptions of the present embodiments and various modification examples. Those skilled in the art can understand that the present embodiments and various modification examples are just examples, and within the scope of the invention described in the claims, various changes in the embodiments can be made. The technical scope of the present disclosure should be determined based on the scope of the invention described in the claims and its equivalent scope.

[0114] In the above-described embodiments and various modification examples, the central position (xc, yc) located in the central portion and the peripheral position (xe, ye) located in the peripheral portion in the high-definition ADB lighting pattern AP are defined. At this time, the difference in luminance between the first pixel at the central position (xc, yc) in the first image I1 and the first pixel at the central position (xc, yc) in the composite image Ic may also be smaller than the difference in luminance between the second pixel at the peripheral position (xe, ye) in the first image I1 and the second pixel at the peripheral position (xe, ye) in the composite image Ic ( Figures 5 to 7 ).

[0115] In the high-definition ADB lighting pattern, even if, for example, derating control is performed, the central portion is the area where the occupants of the vehicle 1 should look, and it is preferably brightly illuminated. On the other hand, the peripheral portion of the high-definition ADB lighting pattern may not necessarily need to be brightly illuminated compared to the central portion. Thus, the derating function of the present disclosure may not change the entire image uniformly. That is, the derating function of the present disclosure can suppress the further increase in the temperature of the plurality of light sources 451 and form a more appropriate lighting pattern by changing the degree of change in the luminance of the pixels according to the position of the lighting pattern.

[0116] In the second modification example, when the reference image Iref referred to when generating the composite image I(t) is such that the third image I3 and the fourth image are different from each other, not only the first image and the second image, but also an intermediate image between the first image and the second image may be used.

[0117] The third threshold TH3 in the second modification example may also be the first threshold TH1. In other words, the first threshold TH1 as the start temperature of the derating control may also be the same as the third threshold TH3 as the upper limit threshold. The third threshold TH3 may also be the second threshold TH2. In other words, the second threshold TH2 as the end temperature of the derating control may also be the same as the third threshold TH3 as the upper limit threshold.

[0118] Each of the functions of the ADB control unit 47, the light source control unit 453, or the integrated control unit 473 described so far can be implemented by a general-purpose microprocessor that cooperates with a general-purpose memory. Examples of the general-purpose microprocessor include a CPU, an MPU, and a GPU. Examples of the general-purpose memory include a ROM or a RAM. In this case, a computer program for executing the above-described processing can be stored in the ROM. The ROM is an example of a non-transitory computer-readable medium. The general-purpose microprocessor designates at least a part of the computer program stored in the ROM and expands it on the RAM, and cooperates with the RAM to execute the above-described processing. The above-described computer program can be pre-installed in the general-purpose memory, or can be downloaded and installed in the general-purpose memory from an external server device via a communication network. In this case, the external server device is an example of a non-transitory computer-readable medium.

[0119] Each of the functions of the ADB control unit 47, the light source control unit 453, or the integrated control unit 473 described so far can also be implemented by an application specific integrated circuit such as a microcontroller, an ASIC, or an FPGA that can execute the above-described computer program. In this case, the above-described computer program is pre-installed in a storage element included in the application specific integrated circuit. The storage element is an example of a non-transitory computer-readable medium. Each of the functions of the processing unit 131 can also be implemented by a combination of a general-purpose microprocessor and an application specific integrated circuit.

[0120] This application claims priority based on Japanese Application No. 2022-190138 filed on November 29, 2022, and Japanese Application No. 2023-106027 filed on June 28, 2023, and incorporates by reference the entire contents described in the above Japanese applications.

Claims

1. A control device, which is a control device for a vehicle lamp, and is characterized in that, the vehicle lamp includes: a plurality of light sources arranged in a matrix; a temperature acquisition unit that acquires the temperature of at least a part of the plurality of light sources; a control unit that individually controls the lighting brightness of the plurality of light sources; and the control device; the control device includes: an image generation unit that outputs an image representing the lighting brightness of each of the plurality of light sources arranged in a matrix as the brightness of pixels corresponding to the respective light sources; a storage unit that stores a first image representing a first brightness distribution of the lighting brightness and a second image representing a second brightness distribution of the lighting brightness, the average brightness of which is lower than the average brightness of the first image; the control unit individually controls the lighting brightness of the plurality of light sources based on the image output from the image generation unit, when the temperature acquired by the temperature acquisition unit is below a first threshold, the image generation unit outputs the first image to the control unit, when the temperature acquired by the temperature acquisition unit is higher than the first threshold, a composite image based on the first image and the second image is generated according to the temperature, and the composite image is output to the control unit, that is, the derating control is started.

2. The control device according to claim 1, characterized in that, the image generation unit changes the influence degree, i.e., the composite ratio, of the first image in the composite image according to the temperature.

3. The control device according to claim 2, characterized in that, when the temperature is higher than the first threshold, the lower the temperature, the greater the composite ratio made by the image generation unit.

4. A control device, which is a control device for a vehicle lamp, and is characterized in that, the vehicle lamp includes: a plurality of light sources arranged in a matrix; a temperature acquisition unit that acquires the temperature of at least a part of the plurality of light sources; the control device that individually controls the lighting brightness of the plurality of light sources; a storage unit that stores an image representing the lighting brightness of each of the plurality of light sources arranged in a matrix as the brightness of pixels corresponding to the respective light sources; the storage unit stores a first image representing a first brightness distribution of the lighting brightness and a second image representing a second brightness distribution of the lighting brightness, the average brightness of which is lower than the average brightness shown in the first image, when the temperature acquired by the temperature acquisition unit is below a first threshold, the control device lights the plurality of light sources with the first brightness distribution shown in the first image, and when the temperature acquired by the temperature acquisition unit is higher than the first threshold, a composite image based on the first image and the second image is generated according to the temperature, and the plurality of light sources are lit with the brightness distribution shown in the composite image, that is, the derating control is started.

5. The control device according to claim 4, characterized in that, the control device changes the influence degree, i.e., the composite ratio, of the first image in the composite image according to the temperature.

6. The control device according to claim 5, characterized in that, When the temperature is higher than the first threshold, the lower the temperature, the greater the synthesis ratio the control device makes.

7. The control device according to claim 1 or 4, characterized in that The vehicle lamp is configured to form a specific light distribution pattern. When a central position in the central part and a peripheral position in the peripheral part in the light distribution pattern are defined, the difference in brightness between a first pixel at the central position in the first image and a first pixel at the central position in the synthesized image is smaller than the difference in brightness between a second pixel at the peripheral position in the first image and a second pixel at the peripheral position in the synthesized image.

8. The control device according to claim 1 or 4, characterized in that When the temperature obtained by the temperature acquisition unit is higher than the first threshold and lower than or equal to a second threshold higher than the first threshold, the control device lights the plurality of light sources according to the brightness distribution shown in the synthesized image based on the temperature. When the temperature obtained by the temperature acquisition unit is higher than the second threshold, the plurality of light sources are lit with the second brightness distribution shown in the second image.

9. The control device according to claim 1, characterized in that After the derating control is started, when the temperature obtained by the temperature acquisition unit is higher than a third threshold, the image generation unit generates the synthesized image in such a way as to lower the temperature.

10. The control device according to claim 9, characterized in that The third threshold is the first threshold.

11. The control device according to claim 9, characterized in that The synthesized image I(t) generated at time t is a synthesized image of the synthesized image I(t - 1) generated immediately before and a third image with an average brightness lower than that of the synthesized image I(t - 1).

12. The control device according to claim 11, characterized in that The third image is the second image.

13. The control device according to claim 9, characterized in that After the derating control is started, when the temperature obtained by the temperature acquisition unit is lower than a fourth threshold lower than the third threshold, the image generation unit generates the synthesized image in such a way as to raise the temperature.

14. The control device according to claim 13, characterized in that The synthesized image I(t) generated at time t is a synthesized image of the synthesized image I(t - 1) generated immediately before and a fourth image with an average brightness higher than that of the synthesized image I(t - 1).

15. The control device according to claim 14, characterized in that The fourth image is the first image.

16. A computer program, which can be executed by a control device mounted on a vehicle lamp, characterized in that The vehicle lamp includes: a plurality of light sources arranged in a matrix; a temperature acquisition unit that acquires the temperature of at least a part of the plurality of light sources; a control unit that individually controls the lighting brightness of the plurality of light sources; the control device. By executing the computer program, the control device outputs an image in which the lighting brightness of each of the plurality of light sources arranged in a matrix is represented as the brightness of a pixel corresponding to each light source. Based on the output image, the lighting brightness of the plurality of light sources is controlled individually. A first image representing a first brightness distribution of the lighting brightness and a second image representing a second brightness distribution of the lighting brightness with an average brightness lower than the average brightness of the first image are stored. When the temperature obtained by the temperature acquisition unit is below a first threshold, the first image is output to the control unit. When the temperature obtained by the temperature acquisition unit is higher than the first threshold, a composite image based on the first image and the second image is generated according to the temperature, and the composite image is output to the control unit, that is, derating control is started.

17. A vehicle lamp, characterized in that, It includes: a plurality of light sources arranged in a matrix; a temperature acquisition unit that acquires the temperature of at least a part of the plurality of light sources; an image generation unit that outputs an image in which the lighting brightness of each of the plurality of light sources arranged in a matrix is represented as the brightness of a pixel corresponding to each light source; a control unit that individually controls the lighting brightness of the plurality of light sources based on the image output from the image generation unit; a storage unit that stores a first image representing a first brightness distribution of the lighting brightness and a second image representing a second brightness distribution of the lighting brightness with an average brightness lower than the average brightness of the first image. When the temperature obtained by the temperature acquisition unit is below a first threshold, the image generation unit outputs the first image to the control unit. When the temperature obtained by the temperature acquisition unit is higher than the first threshold, the image generation unit generates a composite image based on the first image and the second image according to the temperature, and outputs the composite image to the control unit, that is, derating control is started.

Images