Vehicle lamp and vehicle lamp system

Abstract

The headlamp (10) is mounted on a vehicle that is driven to turn by tilting a vehicle body in a bending direction, and is provided with: a light distribution determination unit (15) that determines a light distribution pattern on the basis of the tilt angle of the vehicle body and light spots included in an image obtained by capturing the surroundings of the vehicle; a light source unit that divides the illuminable region into a plurality of regions and that can independently control the illumination state of each region; and a lighting control unit (16) that controls the light source unit so as to form a light distribution pattern. When the illumination state of a specific area changes for a predetermined time or more, the illumination state of the specific area is fixed.

Description

Technical Field

[0001] The present invention relates to a vehicle lamp and a vehicle lamp system including the vehicle lamp. Background Art

[0002] Patent Document 1 discloses a vehicle lamp system that performs ADB (Adaptive Driving Beam) control for dynamically controlling the light distribution pattern of high beams based on the state around the vehicle. In this vehicle lamp system, a vehicle included in an image obtained by an imaging device that captures the front area of the vehicle is detected by performing image processing on the image, and a light distribution pattern is formed such that a light-shielding area is formed at the position where the detected vehicle exists.

[0003] Prior Art Documents

[0004] Patent Documents

[0005] Patent Document 1: Japanese Patent Application Laid-Open No. 2015-064964 Summary of the Invention

[0006] Technical Problem to be Solved by the Invention

[0007] In addition, in a two-wheeled vehicle, a vehicle lamp system that performs ADB control is also required.

[0008] Here, a two-wheeled vehicle tilts its body to drive through a turn, so when the front of the vehicle is photographed using a camera mounted on the two-wheeled vehicle, the image is tilted when driving through a turn compared to when driving straight. When performing ADB control, the area to be shaded moves significantly in the image, so processing for continuously determining the area to be shaded from the tilted image is required, and the processing burden on the vehicle lamp system is high.

[0009] Thus, due to the unique situation of two-wheeled vehicles, when driving through a turn, the processing burden of the image becomes large, and it is difficult to directly apply the ADB control applicable to four-wheeled vehicles to two-wheeled vehicles. In particular, for two-wheeled vehicles, cost reduction is mostly required compared to four-wheeled vehicles, so a technology for ADB control with a more difficult-to-increase processing burden is required.

[0010] Therefore, the inventors of the present application have studied a vehicle lighting system for a two-wheeled vehicle that performs ADB control for a two-wheeled vehicle suitable for suppressing an increase in processing load, and determines a light distribution pattern based on detecting a vehicle from light spots in an image obtained from an imaging device. Here, among the light spots included in the image obtained from the imaging device, in addition to the spontaneous light emission from the headlights of an oncoming vehicle and the taillights of a preceding vehicle, there is also light that is irradiated from the headlights of the own vehicle and reflected from a reflector such as a sign. Therefore, if the light distribution pattern is determined based on the light spots included in the image, there may occur a so-called light flickering phenomenon in which the light is repeatedly irradiated and non-irradiated to the reflector.

[0011] An object of the present invention is to suppress a light flickering phenomenon in ADB control in a vehicle lighting device and a vehicle lighting system mounted on a vehicle that turns by tilting the vehicle body in the bending direction.

[0012] Technical means for solving the problem

[0013] A vehicle lighting device according to one aspect of the present invention is mounted on a vehicle that turns by tilting the vehicle body in the bending direction.

[0014] A light distribution determination unit that determines a light distribution pattern based on the tilt angle of the vehicle body and light spots included in an image obtained by photographing the surroundings of the vehicle.

[0015] A light source unit in which an illuminable area of the light source unit is divided into a plurality of areas, and the lighting state of each area can be independently controlled.

[0016] A lighting control unit that controls the light source unit to form the light distribution pattern.

[0017] When the lighting state of a specific one of the areas changes more than a specified number of times within a specified time, the lighting state of the specific area is fixed.

[0018] Effect of the invention

[0019] According to the present invention, in a vehicle lighting device and a vehicle lighting system mounted on a vehicle that turns by tilting the vehicle body in the bending direction, it is possible to suppress a light flickering phenomenon during ADB control. Description of the drawings

[0020] Figure 1 It is a perspective view of a motorized two-wheeled vehicle including a headlight according to the present embodiment.

[0021] Figure 2 It is a block diagram of a vehicle lighting system.

[0022] Figure 3It is a cross-sectional view of the structure of an exemplary high-beam lamp unit.

[0023] Figure 4 It is an example Figure 3 A perspective view of the structure of the light source unit included in the high-beam lamp unit.

[0024] Figure 5 It is a diagram for explaining the high-beam light distribution pattern during straight travel.

[0025] Figure 6 It is a diagram for explaining the high-beam light distribution pattern during turning.

[0026] Figure 7 It is a diagram of an example of an image of the front of the vehicle being captured.

[0027] Figure 8 It is an example of Figure 7 A diagram of a binary image generated by binarizing the image.

[0028] Figure 9 It is for explaining Figure 8 A diagram of the high-beam light distribution pattern determined based on the binary image.

[0029] Figure 10 It is an example of Figure 9 A diagram of a binary image generated by binarizing an image of the front of the vehicle on which the high-beam light distribution pattern is formed.

[0030] Figure 11 It is for explaining Figure 10 A diagram of the high-beam light distribution pattern determined based on the binary image.

[0031] Figure 12 A diagram of an example of the lighting and extinguishing state information of the light source of the high-beam lamp unit.

[0032] Figure 13 It is a block diagram showing another example of the structure of a vehicle lighting system.

[0033] Figure 14 It is a block diagram showing another example of the structure of a vehicle lighting system. Detailed Description of the Invention

[0034] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In the drawings, arrow U indicates the upward direction of the illustrated structure. Arrow D indicates the downward direction of the illustrated structure. Arrow F indicates the front direction of the illustrated structure. Arrow B indicates the rear direction of the illustrated structure. Arrow R indicates the right direction of the illustrated structure. Arrow L indicates the left direction of the illustrated structure. These directions are relative directions set for the Figure 1 motorcycle 1 shown.

[0035] Figure 1 Reference numeral 1 denotes a two - wheeled motor vehicle according to the present embodiment. The two - wheeled motor vehicle 1 travels along a turn (curved road) of a road by tilting the vehicle body in the bending direction.

[0036] As Figure 1 shown, the two - wheeled motor vehicle 1 is equipped with a headlight 10. The headlight 10 is mounted on the front part of the vehicle and is a lamp capable of irradiating the front of the vehicle. The headlight 10 includes a low - beam lamp unit 11 and a high - beam lamp unit 12. The headlight 10 is an example of a vehicle lamp.

[0037] Figure 2 is a block diagram of a vehicle lamp system 20 mounted on the two - wheeled motor vehicle 1. As Figure 2 shown, the vehicle lamp system 20 includes a headlight 10 and a speed sensor 21. In addition, sensors other than the speed sensor 21 for detecting the state of the vehicle may be provided in the vehicle lamp system 20.

[0038] The headlight 10 includes a tilt - angle sensor 13, an imaging device 14, a light - distribution determination unit 15, and a lighting control unit 16. The tilt - angle sensor 13 is a sensor capable of detecting the tilt angle (so - called bank angle) when the vehicle body of the two - wheeled motor vehicle 1 tilts left and right with respect to the plumb line. The tilt - angle sensor 13 is constituted by, for example, a gyro sensor.

[0039] The imaging device 14 is configured to image the front of the vehicle. The imaging device 14 has sensitivity in the visible light region and images the light irradiated from the headlight 10 and reflected by an object in front of the vehicle, and the light spontaneously emitted from an object in front of the vehicle. The imaging device 14 is constituted by, for example, a camera.

[0040] The light - distribution determination unit 15 is configured to determine the light - distribution pattern of the headlight 10 based on the tilt angle of the vehicle body and the light points included in the image obtained by imaging the front of the vehicle. Specifically, the tilt - angle sensor 13, the imaging device 14, and the speed sensor 21 are connected to the light - distribution determination unit 15. The light - distribution determination unit 15 determines the light - distribution pattern based on the respective information output from the tilt - angle sensor 13, the imaging device 14, and the speed sensor 21. The light - distribution determination unit 15 determines and updates the light - distribution pattern at a prescribed interval. For example, the light - distribution determination unit 15 determines and updates the light - distribution pattern 60 times within 1 second. The light - distribution determination unit 15 can be implemented by a general - purpose memory and a general - purpose microprocessor that cooperates with the general - purpose memory. As the general - purpose microprocessor, a CPU, an MPU, or a GPU can be exemplified.

[0041] The lighting control unit 16 controls the operation of the headlamp 10 to form the light distribution pattern determined by the light distribution determination unit 15. Specifically, the lighting control unit 16 is connected to the light distribution determination unit 15. In addition, the lighting control unit 16 is connected to the low beam lamp unit 11 and the high beam lamp unit 12. The lighting control unit 16 controls the operations of the low beam lamp unit 11 and the high beam lamp unit 12 based on the light distribution pattern output by the light distribution determination unit 15.

[0042] Figure 3 is a vertical cross-sectional view showing a schematic structure of the headlamp 10. As Figure 3 shown, the headlamp 10 includes a lamp body 17 and a transparent cover 18. The lamp body 17 has an opening on the front side of the vehicle. The transparent cover 18 is installed so as to cover the opening of the lamp body 17. A lamp chamber 19 is formed by the lamp body 17 and the transparent cover 18.

[0043] Inside the lamp chamber 19, the low beam lamp unit 11, the high beam lamp unit 12, the tilt angle sensor 13, the imaging device 14, the light distribution determination unit 15, and the lighting control unit 16 are housed. In addition, in Figure 3 , although the low beam lamp unit 11 is not shown, it is housed in the lamp chamber 19 of the headlamp 10 in the same manner as the high beam lamp unit 12.

[0044] The high beam lamp unit 12 is a so-called projection type lamp, and includes a projection lens 121, a light source unit 122, and a bracket 123. The bracket 123 is installed on the lamp body 17 via a support member (not shown).

[0045] The projection lens 121 is disposed on the optical axis Ax extending in the vehicle front-rear direction. The projection lens 121 is a plano-convex aspherical lens having a convex front surface and a flat rear surface. The peripheral portion of the projection lens 121 is held at the front end side of the bracket 123. The projection lens 121 forms a prescribed light distribution pattern by irradiating the light from the light source unit 122 forward of the lamp.

[0046] The light source unit 122 is held at the rear end side of the bracket 123. The light source unit 122 includes a light source 1221 and a support plate 1222. The light source 1221 is fixed to the front surface of the support plate 1222. The light source 1221 is disposed so as to face forward in the direction of the optical axis Ax. The light source 1221 is composed of a semiconductor light source such as a light emitting diode (LED), an EL element, or an LD element, for example.

[0047] Figure 4 is a perspective view showing a schematic structure of the light source unit 122. As Figure 4As shown, the light source unit 122 has a plurality of light sources 1221. For example, the light source unit 122 has light sources 1221a to 1221g arranged in a row of 7 columns and 1 row in the left-right direction (a direction orthogonal to the optical axis Ax). The light sources 1221a to 1221g are configured as an LED array. In addition, the number and arrangement of the light sources 1221 constituting the LED array are not limited to the structure of this example.

[0048] Each light source 1221 is electrically connected to the lighting control unit 16. The light sources 1221 are individually driven and controlled by the lighting control unit 16. The lighting control unit 16 has, for example, an LDM (LED Driving Modulator, LED drive modulator) that controls the drive current supplied to the light sources 1221.

[0049] Each light source 1221 corresponds to each of a plurality of regions that form an illuminable region in front of the vehicle, and the light from each light source 1221 irradiates the corresponding independent region. By individually driving and controlling the light sources 1221 by the lighting control unit 16, the lighting state of each region in the illuminable region can be independently controlled.

[0050] Figure 5 and Figure 6 represents the light distribution pattern formed by the headlamp 10 mounted on the motorcycle 1. In Figure 5 and Figure 6 , H-H represents the horizontal direction, and V-V represents the vertical direction. In addition, in Figure 6 , only the light distribution pattern PH for high beam is shown.

[0051] Figure 5 represents the light distribution pattern formed in front of the vehicle when the motorcycle 1 is in a straight-ahead state, that is, when the motorcycle 1 is traveling with the body perpendicular to the road surface. The case where the body of the motorcycle 1 is in a straight-ahead state includes, for example, the case where it is perpendicular to the body and the case where the inclination of the body is within ±10 degrees.

[0052] The light distribution pattern is formed on a hypothetical vertical screen arranged at a specified position in front of the vehicle, for example, at a position 100 m in front of the vehicle. In this example, the light distribution pattern includes a light distribution pattern PH for high beam and a light distribution pattern PL for low beam. The light distribution pattern PH for high beam is the light distribution pattern formed by the high-beam lamp unit 12. The light distribution pattern PL for low beam is the light distribution pattern formed by the low-beam lamp unit 11.

[0053] The light distribution pattern PH for high beam is a light distribution pattern formed by arranging a plurality of longitudinally long partial patterns PHa to PHg side by side in the horizontal direction. Each of the partial patterns PHa to PHg is formed by the light emitted from light sources 1221a to 1221g, respectively. The partial pattern PHa is formed by the light source 1221a. The partial pattern PHb is formed by the light source 1221b. The partial pattern PHc is formed by the light source 1221c. The partial pattern PHd is formed by the light source 1221d. The partial pattern PHe is formed by the light source 1221e. The partial pattern PHf is formed by the light source 1221f. The partial pattern PHg is formed by the light source 1221g.

[0054] In the ADB (Adaptive Driving Beam) mode, the light distribution pattern PH for high beam is formed into different forms of light distribution patterns for high beam according to the conditions of the host vehicle and the preceding vehicle (oncoming vehicle or vehicle traveling ahead) traveling in front of the vehicle through the combination of formation and non-formation of each of the partial patterns PHa to PHg.

[0055] Specifically, the light distribution determination unit 15 detects the condition of the host vehicle based on the inclination angle of the vehicle body detected by the inclination angle sensor 13. In addition, the light distribution determination unit 15 detects the condition of the host vehicle including the running and stopping of the host vehicle based on the vehicle speed detected by the speed sensor 21. In addition, the light distribution determination unit 15 detects the condition of the preceding vehicle including the presence or absence and the presence position of the preceding vehicle based on the light points included in the image acquired by the imaging device 14. Moreover, the light distribution determination unit 15 defines a light shielding range for not irradiating light to the preceding vehicle. The light distribution determination unit 15 determines the light distribution pattern PH for high beam in such a manner that the light shielding range is not irradiated.

[0056] For example, as Figure 5 and Figure 6 shown, when the oncoming vehicle 30 is traveling in front of the right side of the motorized two-wheeler 1, the light distribution determination unit 15 defines a light shielding range A ( Figure 5 ) for not irradiating light to the oncoming vehicle 30. Then, the light distribution determination unit 15 determines the light distribution pattern PH for high beam in which a part of the partial pattern is a non-irradiation area so that light is not irradiated to the light shielding range A.

[0057] As Figure 5 shown, when the motorized two-wheeler 1 is traveling in a state where the vehicle body is perpendicular to the road surface, the light distribution determination unit 15 determines the light distribution pattern PH for high beam in which the partial patterns PHf and PHg corresponding to the area where the oncoming vehicle 30 exists are non-irradiation areas. In addition, the "non-irradiation area" may also include an area where light is irradiated with a low illuminance so as not to cause glare to the driver of the oncoming vehicle.

[0058] On the other hand, as Figure 6As shown, when the body of the two-wheeled motor vehicle 1 is in a turning state, for example, when traveling in a right-turning manner while tilting the body to the right with respect to the road surface (tilt angle θ), the light distribution determination unit 15 determines the partial patterns PHe and PHf corresponding to the area where the oncoming vehicle 30 exists as the non-irradiation area of the high-beam light distribution pattern PH.

[0059] The lighting control unit 16 controls the lighting and extinguishing of each light source 1221 separately based on the high-beam light distribution pattern PH determined by the light distribution determination unit 15. Specifically, the lighting control unit 16 sets the light source 1221 corresponding to the partial pattern as the irradiation area to the lit state, and sets the light source 1221 corresponding to the partial pattern as the non-irradiation area to the extinguished state or the low illuminance state. For example, when the dimming method of the light source is analog dimming, the lighting control unit 16 adjusts the DC level of the drive current flowing through the light source 1221. For example, when the dimming method of the light source is PWM (Pulse Width Modulation) dimming, the lighting control unit 16 switches the current flowing through the light source 1221 and adjusts the ratio of the on-time to thereby adjust the average level of the drive current.

[0060] For example, in Figure 5 In the case of the high-beam light distribution pattern PH shown, the lighting control unit 16 sets the light sources 1221f and 1221g corresponding to the partial patterns PHf and PHg to the extinguished state, and sets the remaining light sources 1221a to 1221e to the lit state. Additionally, for example, in Figure 6 In the case of the high-beam light distribution pattern PH shown, the lighting control unit 16 sets the light sources 1221e and 1221f corresponding to the partial patterns PHe and PHf to the extinguished state, and sets the remaining light sources 1221a to 1221d, 1221g to the lit state.

[0061] In such ADB control of the two-wheeled motor vehicle 1, the two-wheeled motor vehicle 1 tilts the body to drive through the turn. Therefore, compared with when going straight, the image obtained by the imaging device 14 is tilted when driving through the turn. The area to be shaded during ADB control moves greatly in the image, so it is necessary to continuously determine the area to be shaded from the tilted image, and the processing burden on the vehicle lighting system is high.

[0062] However, as described above, the light distribution determination unit 15 according to the present embodiment detects the oncoming vehicle based on the light spots included in the image, and thus can perform ADB control suitable for a two-wheeled motor vehicle with an increased processing burden suppressed.

[0063] Next, using Figures 7 to 11 , the method for the light distribution determination unit 15 to detect the light spots included in the image and the method for determining the light distribution pattern based on the detected light spots will be described in more detail.

[0064] First, the light distribution determination unit 15 determines a high beam light distribution pattern PH1 in which partial patterns PHa to PHg are set as the illumination area, so that the entire area of the illuminable area in front of the vehicle is illuminated. The lighting control unit 16 drives and controls the light source unit 122 based on the determined high beam light distribution pattern PH1 to turn on the light sources 1221a to 1221g.

[0065] Next, in order to update the high beam light distribution pattern PH, the light distribution determination unit 15 detects a preceding vehicle based on an image in front of the vehicle in which the high beam light distribution pattern PH1 is formed and captured by the imaging device 14. Specifically, the light distribution determination unit 15 generates a binarized image in which the luminance values of the respective pixels in the image are binarized using a threshold value of a specified luminance. Then, the light distribution determination unit 15 detects specified high-luminance pixels included in the binarized image as light points. That is, a light point is an aggregate of one or more high-luminance pixels. The threshold value is appropriately set to a luminance value such that, for example, the light from the headlamp of an oncoming vehicle or the rear lamp of a preceding vehicle can be detected.

[0066] For example, Figure 7 shows an image captured by the imaging device 14. As Figure 7 shown, there are an oncoming vehicle 31, a preceding vehicle 32, and a road sign 33 in the area in front of the vehicle. The headlamp of the oncoming vehicle 31 and the rear lamp of the preceding vehicle 32 are self-luminous bodies and are captured as high-luminance bodies. In addition, the road sign 33 is a light-reflecting object and is captured as a high-luminance body. In addition, the road sign 33 is an example of a light-reflecting object. In addition to road signs, sight guiding signs, billboards, objects having a retroreflective surface in a part visually confirmed from the own vehicle, etc. also belong to light-reflecting objects.

[0067] Figure 8 is a binarized image generated based on Figure 7 In the Figure 8 shown binarized image, in addition to the high-luminance pixels 41 corresponding to the headlamp of the oncoming vehicle 31 and the high-luminance pixels 42 corresponding to the rear lamp of the preceding vehicle 32, high-luminance pixels 43 corresponding to the road sign 33 are also detected as light points.

[0068] Then, the light distribution determination unit 15 defines the area in front of the vehicle overlapping with the determined high-luminance pixels as a light-shielding range, so that light is not irradiated to the area in front of the vehicle overlapping with the high-luminance pixels detected as light points, and thus determines a high beam light distribution pattern PH2 such that the light-shielding range is not irradiated.

[0069] Specifically, as Figure 9As shown, the partial patterns PHa, PHd, PHf, and PHg corresponding to the regions where the oncoming vehicle 31, the preceding vehicle 32, and the road sign 33 exist are determined as the non-irradiation regions of the high beam light distribution pattern PH2. The lighting control unit 16 sets the light sources 1221b, 1221c, and 1221e to the lit state and sets the light sources 1221a, 1221d, 1221f, and 1221g to the extinguished state based on the determined high beam light distribution pattern PH2.

[0070] Next, the light distribution determination unit 15 detects the preceding vehicle based on the image of the front of the vehicle where the high beam light distribution pattern PH2 is formed, which is captured by the imaging device 14, in order to update the high beam light distribution pattern PH.

[0071] For example, Figure 10 is a binary image generated by binarizing the image obtained by photographing the front of the vehicle where the high beam light distribution pattern PH2 shown in Figure 9 is formed. In the binary image shown in Figure 10 the high-brightness pixels 41 corresponding to the headlamps of the oncoming vehicle 31 and the high-brightness pixels 42 corresponding to the rear lamps of the preceding vehicle 32 are detected as light points.

[0072] Then, the light distribution determination unit 15 defines the region in front of the vehicle that overlaps with the high-brightness pixels detected as light points as the shading range, and determines the high beam light distribution pattern PH3 in such a way as not to irradiate the shading range. Specifically, as shown in Figure 11 the partial patterns PHd, PHf, and PHg corresponding to the regions where the oncoming vehicle 31 and the preceding vehicle 32 exist are determined as the non-irradiation regions of the high beam light distribution pattern PH3. The lighting control unit 16 sets the light sources 1221a, 1221b, 1221c, and 1221e to the lit state and sets the light sources 1221d, 1221f, and 1221g to the extinguished state based on the determined high beam light distribution pattern PH3.

[0073] In this way, when detecting the preceding vehicle based on the light points included in the image obtained by photographing the front of the vehicle, in addition to the spontaneous light emission from the headlamps of the oncoming vehicle 31 and the rear lamps of the preceding vehicle 32, the light irradiated from the headlamps 10 of the own vehicle and reflected by reflectors such as the road sign 33 is also detected as a light point. Therefore, when defining the shading range based on the light points included in the image to form the high beam light distribution pattern PH, the shading range is also defined at the position where the reflector exists, so that the light does not irradiate the reflector. As a result, no light points are detected from the pixels corresponding to the reflector in the image obtained later, so the light will be irradiated to the reflector again. As a result, the light is repeatedly irradiated and not irradiated to the reflector, generating a light flicking phenomenon, which is visually recognized as flicker by the driver and the imaging device.

[0074] Therefore, the headlamp 10 according to the present embodiment is configured such that when the lighting state of a specific area in the illuminable area in front of the vehicle changes more than a specified number of times within a specified time, the lighting state of the specific area is fixed. Specifically, when the state of the light source unit 122 that irradiates the specific area changes more than a specified number of times within a specified time, the light distribution determination unit 15 controls the lighting control unit 16 to fix the state of the light source unit 122 that irradiates the specific area.

[0075] For example, as Figure 2 shown, the lighting control unit 16 is configured to output the state of the light source unit 122 of the high beam lamp unit 12 to the light distribution determination unit 15. Each time the light distribution pattern is updated by the light distribution determination unit 15, the lighting control unit 16 controls the operation of the light source unit 122 of the high beam lamp unit 12, and outputs the state of the light source unit 122 to the light distribution determination unit 15.

[0076] Based on the state of the light source unit 122 output from the lighting control unit 16, when the state of the light source unit 122 changes continuously at least twice or more, the light distribution determination unit 15 controls the lighting control unit 16 to fix the state of the changed light source unit 122.

[0077] In this example, each time the light distribution pattern is updated, the lighting control unit 16 controls the lighting and extinguishing states of the respective light sources 1221 of the light source unit 122, and outputs the lighting and extinguishing states of the respective light sources 1221 to the light distribution determination unit 15. The light distribution determination unit 15 controls the lighting control unit 16 to fix the lighting and extinguishing states of the light sources 1221 in which the lighting and extinguishing states output from the lighting control unit 16 change continuously at least twice or more. Here, the count is that the lighting and extinguishing state changes once when the light source 1221 changes from the lit state to the extinguished state, or the lighting and extinguishing state changes once when the light source 1221 changes from the extinguished state to the lit state.

[0078] Figure 12 Data indicating the lighting and extinguishing states of the respective light sources 1221a to 1221g output from the lighting control unit 16 at a specified reception interval (frame rate) and acquired by the light distribution determination unit 15. In Figure 12 , ON indicates the lit state of the light source 1221. OFF means the extinguished state of the light source 1221.

[0079] The light distribution determination unit 15 determines, for example, whether the lighting and extinguishing states of the light source 1221 change continuously three times from ON to OFF, from OFF to ON, and from ON to OFF within 4 frames. The time for acquiring the data of 4 frames is an example of the specified time for the state change of the light source unit. Three times is an example of the specified number of times for the state change of the light source unit.

[0080] Specifically, the light distribution determination unit 15 represents the lighting and extinguishing states of each light source 1221 between 4 frames using 1-byte variables and stores them as bit flags in the memory. When the stored bit flags represent a specific value, it is determined that the lighting and extinguishing states of the light source 1221 corresponding to the bit flags change continuously. The specific value is, for example, appropriately set to the value represented by the bit flag output when the lighting and extinguishing states of the light source 1221 change continuously.

[0081] In addition, the determination of whether the lighting and extinguishing state changes can also be performed for every 4 frames (for example, between frame 1 and frame 4, between frame 5 and frame 8, …). Alternatively, the determination of whether the lighting and extinguishing state changes can also be performed for every 1 frame among the most recent 4 frames (for example, between frame 1 and frame 4, between frame 2 and frame 5, …).

[0082] In this example, as Figure 12 shown, the lighting and extinguishing state of the light source 1221a changes to ON in the first frame, changes to OFF in the second frame, changes to ON in the third frame, and changes to OFF in the fourth frame. The lighting and extinguishing states of the light sources 1221b and 1221c are in the ON state from the first frame to the fourth frame. The lighting and extinguishing states of the light sources 1221d, 1221e, and 1221f are in the OFF state from the first frame to the fourth frame.

[0083] Therefore, the light distribution determination unit 15 determines that the lighting and extinguishing state of the light source 1221a changes continuously 3 times from ON to OFF, from OFF to ON, and from ON to OFF. Then, the light distribution determination unit 15 controls the lighting control unit 16 to fix the lighting and extinguishing state of the light source 1221a. In addition, in this example, the area illuminated by the light emitted from the light source 1221a becomes an example of a specific area.

[0084] For example, when the light source 1221a changes from the extinguished state of the light source to the lit state, the light distribution determination unit 15 outputs control information to the lighting control unit 16 to temporarily lengthen the transition time (gradation time) for increasing the brightness of the light source 1221a. Based on the control information, the lighting control unit 16 adjusts, for example, the increase amount per unit time of the drive current supplied to the light source 1221a to slowly increase the brightness of the light source 1221a. As a result, between multiple frames after the fifth frame, the brightness of the light source 1221a is controlled to gradually increase while the lighting and extinguishing state of the light source 1221a is fixed to the ON state.

[0085] Alternatively, the light distribution determination unit 15 can also be configured to output control information to the lighting control unit 16 to fix the lighting and extinguishing state of the light source 1221a to the same OFF state as that of the 4 frames between multiple frames after the fifth frame. For example, the light distribution determination unit 15 can also be configured to maintain the fixed state for 30 frames starting from when it is determined that the lighting and extinguishing state has changed 3 times.

[0086] As described above, according to the headlamp 10 according to the present embodiment, even when the light-shielding range is defined based on the light spots included in the image, the lighting state of a specific area where the lighting state has changed more than a specified number of times within a specified time is fixed. Therefore, it is possible to suppress the light flicker phenomenon caused by repeated irradiation and non-irradiation of light on the reflector.

[0087] In addition, in the present embodiment, the imaging device 14 is included in the headlamp 10. Specifically, the imaging device 14 is arranged in the lamp chamber 19. Thereby, it is possible to omit processes such as calibration between the imaging device 14 and the light distribution determination unit 15. For example, in the case of a two-wheeled motor vehicle 1, due to the vehicle body tilt, if the imaging device and the image processing part are arranged away from the ground, complex image processing such as rotating the captured image is required during image processing. In addition, if the imaging device and the image processing part are arranged away from the ground, sometimes parallax correction is required, or the position of the light-shielding range of the light of the lamp deviates from the captured image. However, in the present embodiment, the imaging device 14 is arranged in the same lamp chamber 19 as the light distribution determination unit 15. Therefore, the imaging device 14 and the light distribution determination unit 15 have a structure that tilts together, and complex image processing can be omitted. In addition, since the imaging device 14 is arranged near the light distribution determination unit 15, parallax correction is not required, and it is possible to suppress the deviation of the light-shielding range position relative to the captured image.

[0088] In addition, in the present embodiment, when the lighting and extinguishing states of the light source 1221 change continuously three times among four frames, the light flicker is detected. However, for example, the light flicker may also be detected when the lighting and extinguishing states of the light source 1221 change continuously twice among three frames. Or, for example, the light flicker may also be detected when the lighting and extinguishing states of the light source 1221 change continuously among five or more frames.

[0089] The embodiments of the present invention have been described above, but the technical scope of the present invention should not of course be construed in a limiting manner by the description of the present embodiment. The present embodiment is merely an example, and those skilled in the art can understand that various changes in the embodiments can be made within the scope of the invention described in the claims. The technical scope of the present invention should be determined based on the scope of the invention described in the claims and its equivalent scope.

[0090] In the above embodiment, the tilt angle sensor 13 is included in the headlamp 10. However, for example, as Figure 13 shown, the tilt angle sensor 13 may also be separately configured from the headlamp 10. That is, the vehicle lamp system 20 may also be configured to include the headlamp 10, the tilt angle sensor 13, and the speed sensor 21. The tilt angle sensor 13 and the speed sensor 21 are, for example, as Figure 13As shown, it is connected to the headlamp 10 via the vehicle control unit 22. The vehicle control unit 22 is configured to be able to communicate with the light distribution determination unit 15 through, for example, CAN (Controller Area Network) communication or LIN (Local Interconnect Network) communication.

[0091] In the above-described embodiment, the imaging device 14 is included in the headlamp 10. However, for example, as Figure 14 shown, the imaging device 14 may be separately configured from the headlamp 10 together with the tilt angle sensor 13. That is, the vehicle lighting system 20 may also be configured to include the headlamp 10, the tilt angle sensor 13, the imaging device 14, and the speed sensor 21. For example, as Figure 14 shown, the tilt angle sensor 13, the imaging device 14, and the speed sensor 21 are connected to the headlamp 10 via the vehicle control unit 22. The vehicle control unit 22 is configured to be able to communicate with the light distribution determination unit 15 through, for example, CAN communication or LIN communication.

[0092] In addition, even when the imaging device 14 is not included in the headlamp 10 in this way, if the imaging device 14 is arranged near the headlamp 10, it is also possible to configure the imaging device 14 to tilt together with the light distribution determination unit 15, and complex image processing can be omitted. In addition, if the imaging device 14 is arranged near the headlamp 10, the imaging device 14 can be arranged close to the light distribution determination unit 15, parallax correction can be dispensed with, and deviation of the light shielding range position relative to the captured image can be suppressed.

[0093] In the above-described embodiment, the light distribution determination unit 15 and the lighting control unit 16 are separately configured. However, for example, as Figure 13 、 Figure 14 shown, the light distribution determination unit 15 and the lighting control unit 16 may be integrated into one device 50. Specifically, in the device 50, the light distribution determination unit 15 and the lighting control unit 16 are mounted on the same substrate. In this case, compared with the structure in which the light distribution determination unit 15 and the lighting control unit 16 are respectively mounted on different substrates, wiring and communication between the substrates are not required, generation of communication delay can be suppressed, and in addition, the mounting space can be reduced.

[0094] In the above-described embodiment, the light source unit 122 has an LED array composed of a plurality of light sources 1221a to 1221g, and the lighting control unit 16 is configured to individually drive and control the light sources 1221a to 1221g. However, the light source unit 122 may also be composed of a scanning optical type pattern forming device that scans light from a light source such as a blade scanning type device, a matrix type pattern forming device such as a DMD (Digital Mirror Device) or a liquid crystal device, etc. In these cases, the light distribution determination unit 15 is configured to control the lighting control unit 16 to fix the lighting state of the light source of the blade scanning type device, the orientation of the mirrors of the DMD, the state of the liquid crystal elements of the liquid crystal device, etc., which are the states of the light source unit. More specifically, the light distribution determination unit 15 controls the lighting control unit 16 to fix the lighting and extinguishing and lighting intensity during a certain period within one scanning cycle of the light source of the blade scanning type device, the orientation of each mirror of the DMD, the reflection angle, the state of each liquid crystal element of the liquid crystal device, etc.

[0095] In the above-described embodiment, when the state of the light source unit 122 of the high beam lamp unit 12 changes more than a specified number of times within a specified time, the light distribution determination unit 15 fixes the state of the light source unit 122. However, for example, in the case where the headlamp 10 has a turn signal capable of performing ADB control, the light distribution determination unit 15 may also be configured to fix the state of the light source unit when the state of the light source unit of the turn signal changes more than a specified number of times within a specified time.

[0096] In the above-described embodiment, as an example of a vehicle that turns by tilting the vehicle body in the bending direction, a motorcycle 1 is cited. However, the number of wheels of this vehicle is not limited. For example, a vehicle that turns by tilting the vehicle body in the bending direction may also include a three-wheeled motor vehicle, etc.

[0097] This application is based on Japanese Patent Application No. 2022-201510 filed on December 16, 2022, the content of which is incorporated herein by reference.

Claims

1. A vehicle lamp, characterized in that, Mounted on a vehicle that turns by tilting the vehicle body in the bending direction, the vehicle lamp has: A light distribution determination unit that determines a light distribution pattern based on the tilt angle of the vehicle body and light points included in an image obtained by photographing the surroundings of the vehicle; A light source unit that divides an illuminable area into a plurality of areas and can independently control the lighting state of each area; And A lighting control unit that controls the light source unit to form the light distribution pattern, When the lighting state of a specific one of the areas changes more than a specified number of times within a specified time, the lighting state of the specific area is fixed.

2. The vehicle lamp according to claim 1, wherein When the state of the light source unit irradiating a specific one of the areas changes more than a specified number of times within a specified time, the light distribution determination unit controls the lighting control unit to fix the state of the light source unit irradiating the specific area.

3. The vehicle lamp according to claim 1 or 2, wherein The lighting control unit outputs the state of the light source unit to the light distribution determination unit.

4. The vehicle lamp according to claim 3, wherein When the state of the light source unit output from the lighting control unit changes continuously at least twice or more, the light distribution determination unit controls the lighting control unit to fix the changed state of the light source unit.

5. The vehicle lamp according to claim 1 or 2, wherein The light source unit has a plurality of semiconductor light sources for irradiating each of the areas, The lighting control unit is configured to perform drive control on the plurality of semiconductor light sources separately.

6. The vehicle lamp according to claim 5, wherein The lighting control unit outputs the lighting and extinguishing states of the respective semiconductor light sources to the light distribution determination unit, The light distribution determination unit controls the lighting control unit to fix the lighting and extinguishing states of the semiconductor light sources whose lighting and extinguishing states output from the lighting control unit change continuously at least twice or more.

7. The vehicle lamp according to claim 1 or 2, wherein The light distribution determination unit and the lighting control unit are mounted on the same substrate.

8. The vehicle lamp according to claim 1 or 2, wherein The vehicle lamp has a photographing device for photographing the surroundings of the vehicle.

9. A vehicle lighting system, characterized in that, Having: A photographing device that photographs the surroundings of the vehicle; and The vehicle lamp according to claim 1 or 2.

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