Vehicle lighting system

Abstract

To improve the visibility of pedestrians and to raise awareness among them. [Solution] A vehicle lighting system comprising: a headlight with variable light distribution; an object sensor configured to detect objects around the vehicle; and a controller connected to the object sensor and the headlight, respectively, which controls the operation of the headlight based on the detection result by the object sensor, wherein the controller is configured to estimate the position of at least road markings as the object, and the controller controls the headlight to illuminate the front of the vehicle with a beam that at least a portion of which overlaps with the estimated position of the road markings and has a plan view shape that increases in width as it moves away from the vehicle.

Description

Technical Field

[0001] The present disclosure relates to a vehicle lighting system.

Background Art

[0002] Japanese Unexamined Patent Application Publication No. 2020-142796 (Patent Document 1) describes a technique of irradiating light so as to overlap each lane line such as a white line drawn on a road in order to indicate the range of a driving lane on the road.

[0003] According to the above prior art, it is considered to contribute to improving the visibility of lane lines for a driver of a vehicle. However, when there are pedestrians trying to cross the road, there is room for improvement from the viewpoints of improving the visibility of pedestrians for the driver and giving a warning to pedestrians.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] One of the objectives of the specific aspect according to the present disclosure is to provide a technique that can improve the visibility of pedestrians and give a warning to pedestrians.

Means for Solving the Problems

[0006] A vehicle lighting system according to one aspect of the present disclosure includes a headlamp with variable light distribution, an object sensor configured to be able to detect objects around the vehicle, a controller connected to each of the object sensor and the headlamp, and configured to control the operation of the headlamp based on the detection result by the object sensor Includes, The controller is configured to be able to estimate the position of at least the road markings as the object, The controller controls the headlights to project a beam in front of the vehicle, the beam having a plan view shape in which at least a portion of the beam coincides with the estimated position of the lane markings and which increases in width as it moves away from the vehicle. This is a vehicle lighting system.

[0007] The above configuration makes it possible to improve the visibility of pedestrians and to draw their attention to safety. [Brief explanation of the drawing]

[0008] [Figure 1] Figure 1 is a block diagram showing the configuration of a vehicle lighting system according to the first embodiment. [Figure 2] Figure 2 is a block diagram showing an example of a computer system configuration. [Figure 3] Figures 3(A) and 3(B) are schematic diagrams illustrating examples of the configurations of the left and right headlights. [Figure 4] Figure 4 shows an example configuration of a high-beam unit capable of selectively emitting high beams. [Figure 5] Figure 5 is a diagram illustrating a specific example of illumination light emitted by a vehicle lighting system. [Figure 6] Figure 6(A) schematically shows the illumination of the lane marking-enhanced beam as seen from the driver's seat of the vehicle. Figure 6(B) schematically shows the illumination of the lane marking-enhanced beam of the comparative example as seen from the driver's seat of the vehicle. [Figure 7] Figure 7 is a flowchart showing the operation procedure of the vehicle lighting system according to the first embodiment. [Figure 8] Figure 8 is a diagram illustrating a specific example of the illumination light in a modified form. [Figure 9]Figure 9(A) is a diagram illustrating a specific example of the illumination light in the modified example. Figure 9(B) is a timing chart showing the irradiation timing of each segment in the line-emphasized beam of the modified example. [Figure 10] Figure 10(A) is a diagram illustrating a specific example of the illumination light in the modified example. Figure 10(B) is a timing chart showing the irradiation timing of each segment in the line-enhanced beam of the modified example. [Figure 11] Figure 11(A) is a diagram illustrating a specific example of the illumination light in the modified example. Figure 11(B) is a timing chart showing the irradiation timing of each segment in the line-enhanced beam of the modified example. [Figure 12] Figure 12(A) is a diagram illustrating a specific example of the illumination light in the modified example. Figure 12(B) is a timing chart showing the irradiation timing of each segment in the line-enhanced beam of the modified example. [Figure 13] Figure 13 is a diagram illustrating the relationship between two frames in apparent motion. [Figure 14] Figure 14 illustrates the relationship between presentation time, blackout time, and on-time interval at several frame rates. [Figure 15] Figures 15(A) and 15(B) show specific examples of the irradiation light in the modified form. [Figure 16] Figures 16(A) to 16(D) show specific examples of the illumination light in the vehicle lighting system of the second embodiment. [Figure 17] Figures 17(A) to 17(D) show modified examples of the illumination light in the vehicle lighting system of the second embodiment. [Figure 18] Figure 18 is a flowchart showing the operation procedure of the vehicle lighting system according to the second embodiment. [Figure 19] Figures 19(A) to 19(C) show specific examples of the illumination light in the vehicle lighting system of the third embodiment. [Figure 20] Figure 20 is a flowchart showing the operation procedure of the vehicle lighting system according to the third embodiment.

Mode for Carrying Out the Invention

[0009] (First Embodiment) FIG. 1 is a block diagram showing the configuration of a vehicle lighting system according to the first embodiment. The illustrated vehicle lighting system includes a controller 1, a camera 2, a millimeter-wave radar 3, a LiDAR (Light Detection And Ranging) 4, a headlight switch 5, map data 6, a GPS sensor 7, a communication unit 8, and a pair of headlights, a right headlight 9R and a left headlight 9L. This vehicle lighting system irradiates light forward of the host vehicle by the right headlight 9R and the left headlight 9L in response to an operation on the headlight switch 5 provided in the host vehicle.

[0010] The controller 1 controls the light irradiation by the right headlight 9R and the left headlight 9L based on the position of an object obtained by the camera 2 or the like. This controller 10 can be configured using a computer system including, for example, a processor (PROCESSOR) 201, a ROM (Read Only Memory) 202, a RAM (Random Access Memory) 203, a storage device (STORAGE) 204, an input / output unit (IF) 205, etc., as shown in FIG. 2. By the program 206 stored in the storage device 204 being read out and executed by the processor 201, each function described later is realized.

[0011] Camera 2, millimeter-wave radar 3, and LiDAR 4 detect the position and type of objects present around the vehicle. These objects include, for example, pedestrians, bicycles (and their drivers), motorcycles, preceding vehicles, oncoming vehicles, and lane markings on the road surface. Lane markings refer to continuous or dashed lines, such as white or amber, placed on the road to delineate driving lanes. Furthermore, the position and type of objects may also be obtained by receiving information from external systems such as road infrastructure (for example, information detected by sensors at intersections) via the communication unit 8. In other words, in this embodiment, at least one of the cameras 2, millimeter-wave radar 3, LiDAR 4, and communication unit 8 functions as an "object sensor."

[0012] Camera 2 detects the position of the aforementioned objects, their type (pedestrians, bicycles, preceding vehicles, oncoming vehicles, etc.), and the distance between the objects and the vehicle by analyzing the images obtained from capturing the space around the vehicle. The image analysis function may also be provided on the controller 1 side.

[0013] Millimeter-wave radar 3 emits radio waves in the frequency band of, for example, 30 GHz to 300 GHz, and detects the position, type, and distance between objects based on the reflected waves generated.

[0014] LiDAR4 detects the position, type, and distance between objects based on the reflected light generated by irradiating them with laser light.

[0015] Map data 6 is data that associates road-related information, specifically road type (national roads, prefectural roads, etc.), number of road lanes, and the location and type of road markings, with the location of each road. By referring to map data 6 according to the location of the vehicle, which is identified by a GPS sensor (not shown), data about the road the vehicle is traveling on can be obtained. This map data 6 may be the map data from a navigation system (not shown) installed in the vehicle, or dedicated map data may be provided.

[0016] The GPS sensor 7 detects the current location by receiving radio waves from the Global Positioning System. This allows the vehicle's current location to be determined.

[0017] The communication unit 8 transmits and receives information via wireless communication. This allows it to receive information from road infrastructure and other external systems.

[0018] The right headlight 9R and the left headlight 9L are mounted in predetermined positions on the left and right sides of the front of the vehicle, and operate in accordance with control signals provided by the controller 1 to illuminate the front of the vehicle with a desired light distribution pattern.

[0019] The right-side headlight 9R is equipped with an ADB unit 51R and a low-beam unit 52R. The ADB unit 51R is configured to emit a normal high beam within the illumination range of the high beam (driving light), and to emit light with a light distribution pattern in which the light illumination range and dimming range can be freely set. In other words, the ADB unit 51R is configured to emit a variable light distribution beam. The low-beam unit 52R is configured to emit a low beam (passing light).

[0020] Similarly, the left headlight 9L is equipped with an ADB unit 51L and a low beam unit 52L. The ADB unit 51L is configured to emit a normal high beam within the illumination range of the high beam (driving light), and to emit light with a light distribution pattern in which the light illumination range and dimming range can be freely set. In other words, the ADB unit 51L is configured to emit a variable light distribution beam. The low beam unit 52L is configured to emit a low beam (passing light).

[0021] The controller 1 described above includes an illumination state setting unit (illumination state setting function) 11, a light distribution control unit (light distribution control function) 12, an object position determination unit (object position determination function) 13, a road surface condition determination unit (road surface condition determination function) 14, a glare detection unit (glare detection function) 15, and an object position estimation unit (object position estimation function) 16, all of which are functions obtained by program execution in the processor.

[0022] The illumination state setting unit 11 sets the light distribution pattern (illumination state) within the high beam illumination range of each ADB unit 51R, 51L based on the detection results from the camera 2, which functions as an object sensor, specifically the position, type, and distance between the detected objects.

[0023] The light distribution control unit 12 generates control signals to realize the light distribution pattern set by the irradiation state setting unit 11 and outputs them to each ADB unit 51R, 51L. The light distribution control unit 12 also outputs control signals to the low beam units 52R, 52L to irradiate them with low beams.

[0024] The object position acquisition unit 13 acquires the position of a specific object from among the objects detected by the camera 2, etc., which functions as an object sensor. The acquisition of the position of a specific object, as referred to here, means acquiring the position of at least the lane markings on the road, and may further include acquiring the positions of pedestrians, oncoming vehicles, preceding vehicles, etc.

[0025] The road surface condition determination unit 14 determines whether the road surface is wet based on the image captured by the camera 2. For example, the road surface condition determination unit 14 can determine whether the road surface is wet based on the brightness of the portion of the road surface included in the image. The road surface condition determination unit 14 may also determine the road surface condition based on weather information obtained through communication with an external source, or based on the detection results of another sensor (e.g., a wetness sensor) not shown.

[0026] The glare detection unit 15 detects the possibility of glare generation caused by the illumination light formed by the right headlight 9R or the left headlight 9L. Further details will be described later.

[0027] The object position estimation unit 16 estimates the position of lane markings when they cannot be partially detected on the road. For example, the position of lane markings is estimated in various cases, such as when part of the lane markings is faded and cannot be detected, when the lane markings disappear due to bending, etc., when driving straight at an intersection or uphill, when lane markings cannot be detected except in the vicinity or far from the vehicle due to bad weather, ambient light, or obstruction by other vehicles, or when lane markings are not approximately parallel to the direction of travel of the vehicle in a parking lot, etc.

[0028] As a method for estimating the position of lane markings by the object position estimation unit 16, for example, the position of lane markings can be estimated based on road data of the current location that can be identified using map data 6 and GPS sensor 7. In this case, the position of lane markings may also be estimated based on the number of lanes, road width and road structure regulations. Furthermore, based on the position of lane markings already detected by the object position detection unit 13, the portion of the lane markings that has not been detected can also be estimated by methods such as linear approximation. In addition, the position of lane markings can also be estimated from the positions of road structures (curbs, guardrails, walls, etc.) and surrounding vehicles that can be detected by the object position detection unit 13. Moreover, lane markings can also be estimated by setting a virtual line that is approximately parallel to the direction of travel of the vehicle.

[0029] Figures 3(A) and 3(B) are schematic diagrams illustrating the configuration examples of the left and right headlights. While each figure shows the configuration example of the left headlight 9L, the configuration is similar for the right headlight 9R. Figure 3(A) schematically shows the configuration of the left headlight 9L in the vehicle lighting system 1 shown in Figure 1. Specifically, the low beam unit 52L illuminates the area in front of the vehicle with a low beam LB, and the high beam unit 51L illuminates the area in front of the vehicle with a high beam HB. The high beam HB may be a selective high beam (ADB). In this configuration example, the illumination range of the high beam HB illuminated by the high beam unit 51L is set so that its lower end position is close to the lower end position of the low beam LB. Furthermore, the configuration example shown in Figure 3(B) is one in which the functions of the low beam unit 52L and the high beam unit 51L are integrated into a high-definition light source unit 53L. In this configuration example, the high beam HB, illuminated by the high-definition light source unit 53L, has its illumination range set such that its lower end position is close to the lower end position of the low beam LB.

[0030] In each of the above configuration examples, the high-beam unit 51L (51R) and the high-definition light source unit 53L (53R), which are capable of emitting a selective high beam, can each be configured, for example, using a light source capable of emitting laser light and an optical deflector such as a MEMS mirror that scans the laser light. Alternatively, the high-beam unit 51L, etc., can be configured using a light source (LED, laser, etc.) and a liquid crystal element that can partially control the transmittance of the light emitted from the light source. Furthermore, the high-beam unit 51L, etc., can also be configured using a light source with a large number of extremely small LEDs densely mounted and a lens optical system that projects the light emitted from the light source.

[0031] Figure 4 shows an example configuration of a high-beam unit capable of selectively emitting high beams. The illustrated high-beam unit 51L (51R) can be configured using a variable light distribution unit that has a light source 60 equipped with multiple light-emitting elements (e.g., LEDs: Light Emitting Diodes) and a lens 61 that projects the light emitted from the light source 60, and is configured to allow individual control of the on / off state and luminous intensity (brightness) of each light-emitting element. By individually controlling the on / off state and luminous intensity of each light-emitting element, it is possible to generate illumination light with a variable light distribution that includes a dimming range 63 at any position in the light irradiation range 62. In this specification, "dimming" is a concept that includes not only relatively reducing the brightness but also reducing the brightness to zero (i.e., blocking the light).

[0032] Figure 5 is a diagram illustrating a specific example of illumination light emitted by a vehicle lighting system. Figure 5 shows a schematic plan view of the vehicle traveling on a road, viewed from above. More specifically, it schematically shows a situation where the vehicle 100 is traveling on a single-lane road and a pedestrian b is located to the right front of the vehicle 100. The vehicle 100 is illuminated by a lane marking beam 110 and a low beam 120. The low beam 120 is formed by the low beam units 52L and 52R and illuminates a range relatively close to the vehicle 100. In addition, the lane marking beam 110 in the illustrated example is illuminated on the road surface to the right front of the vehicle 100. A portion of the lane marking beam 110 on the side closer to the vehicle 100 overlaps with the illumination range of the low beam 120. The lane marking beam 110 is formed by the ADB unit 51R of the right headlight 9R.

[0033] In a plan view, the lane marking enhancement beam 110 is illuminated such that its inner outer edge (first outer edge) 110a, that is, the side closer to the vehicle 100's driving lane (the side closer to the lane marking d), is approximately parallel to the driving lane. The outer edge (second outer edge) 110b, that is, the side further from the vehicle 100's driving lane (the side further from the lane marking d), is illuminated such that it is not parallel to the driving lane. In other words, the outer edge 110b is illuminated such that the distance from the lane marking d gradually increases as it moves away from the vehicle 100. As a result, the lane marking enhancement beam 110 as a whole has a plan view shape in which its width increases as it moves away from the vehicle 100. The width of the lane marking enhancement beam 110 here refers to its length in the direction of the lane width in the figure. It is preferable that the inner outer edge 110a of the lane marking enhancement beam 110 is set relatively outward in the area in front of the vehicle 100 so as not to exceed the optical axis c1 of the ADB unit 51R of the right headlight 9R. This suppresses the reduction in driver visibility due to the light curtain phenomenon in rainy weather, etc. The illumination mode of the white line enhancement beam 110 can be, for example, continuous illumination, but it may also be flashing illumination (intermittent illumination).

[0034] Figure 6(A) schematically shows the illumination of the lane marking enhancement beam as seen from the driver's seat of the vehicle. By illuminating with a lane marking enhancement beam 110 that spreads outward from the vehicle, in addition to the effect of highlighting the lane marking d, if a pedestrian b crossing the road is near the lane marking d, the area 150 at the feet of the pedestrian b is illuminated. The size (area) of this area 150 at the feet of the pedestrian b is larger than that of the comparative example shown in Figure 6(B), namely the area 1150 at the feet of the pedestrian b illuminated by a beam 1110 that narrowly illuminates only the lane marking d. As a result, the visibility of the pedestrian b from the driver's side is improved. Also, the pedestrian will be more likely to notice the approaching vehicle, so it can effectively alert them.

[0035] Figure 7 is a flowchart showing the operation procedure of the vehicle lighting system according to the first embodiment. Note that the order of the processes shown here can be changed as long as it does not result in inconsistencies or contradictions in the information processing results, and other processes not explicitly shown here can also be added.

[0036] If the headlight switch is not in the ON state (step S11; NO), the process in step S11 is repeated. If, after the processes described later in step S12 and onward are executed and the left headlight 9L and right headlight 9R are illuminated, the headlight switch becomes not ON (i.e., OFF), the right headlight 9R and left headlight 9L are turned off based on the control signal from the light distribution control unit 12.

[0037] When the headlight switch 5 is turned on by the driver (step S11; YES), the object position estimation unit 16 of the controller 1 estimates the position of the lane markings using the detection results of the camera 2 and other object sensors, data obtained from the map data 6, the current position detected by the GPS sensor 7, and information acquired by the communication unit 8 as appropriate (step S12).

[0038] The illumination state setting unit 11 sets the illumination state of the lane marking enhancement beam 110 according to the position of the lane markings estimated by the object position estimation unit 16. A control signal based on this set illumination state is generated by the light distribution control unit 12 and output to the ADB unit 51R of the right headlight 9R, thereby illuminating the lane marking enhancement beam 110 (step S13).

[0039] If a preceding vehicle and / or an oncoming vehicle (collectively referred to as "surrounding vehicles") is detected by the camera 2 or other object sensors (step S14), the object position acquisition unit 13 acquires the position of the surrounding vehicles (step S15). The position of the surrounding vehicles is determined, for example, by the relative angle and relative distance with respect to the vehicle itself.

[0040] The road surface condition determination unit 14 determines whether the road surface is wet or not based on the road portion of the image captured by the camera 2 (step S16). If the road surface is wet (step S16; YES), the glare detection unit 15 detects whether or not there is glare to surrounding vehicles due to specular reflection of the light forming the lane marking enhancement beam on the road surface (step S17).

[0041] Here, the presence or absence of glare due to specular reflection on the road surface is determined by calculating the trajectory of light traveling from the headlight towards the road surface, based on, for example, the illumination state (illumination position) of the lane marking enhancement beam on the road surface, the position of the headlight forming this lane marking enhancement beam (in the above example, the position of the ADB unit 51R of the right headlight 9R), and the relative position of the driver's seat of the surrounding vehicle. If the light can enter the driver's seat of the surrounding vehicle, it is determined as "glare present," and if it does not enter, it is determined as "no glare."

[0042] On the other hand, if the road surface is not wet (step S16; NO), the process in step S17 is omitted and the process proceeds to step S18. In this case, the glare detection unit 15 detects whether or not there is glare on surrounding vehicles due to the direct irradiation of light that forms the lane marking enhancement beam (step S18).

[0043] Here, the presence or absence of glare on surrounding vehicles due to direct illumination can be determined by calculating the trajectory of light traveling from the headlight based on the relative positional relationship between the position of the headlight forming the lane marking enhancement beam (in the above example, the position of the ADB unit 51R of the right headlight 9R) and the position of the driver's seat of the surrounding vehicle. If the light can enter the driver's seat of the surrounding vehicle, it is determined as "glare present," and if it does not enter the driver's seat, it is determined as "no glare."

[0044] If there is glare due to at least one of specular reflection or direct illumination (step S19; YES), the illumination state setting unit 11 sets the illumination state based on the detection result of the glare detection unit 15 to dim the portion of the illumination range of the lane marking enhancement beam 110 that is causing the glare. A control signal based on this set illumination state is generated by the light distribution control unit 12 and output to the ADB unit 51R of the right headlight 9R, thereby partially dimming the lane marking enhancement beam 110 (step S20). In this specification, the concept of "dimming" includes setting the brightness (luminous intensity, illuminance, etc.) of the portion in question to zero. On the other hand, if there is no glare (step S19; NO), the lane marking enhancement beam is not partially dimmed and the process returns to step S11.

[0045] Next, we will describe a modified example of the irradiation method for the line-enhancing beam. Figures 8 and 9(A) illustrate specific examples of the modified illumination. Figure 8, like Figure 5, shows a schematic plan view of the vehicle traveling on the road, viewed from above. The modified lane marking beam 111 is divided into three segments seg1 to seg3 along the direction of travel of the vehicle 100, and is illuminated sequentially starting from segment seg1, which is closer to the vehicle 100. Figure 9(A) schematically represents this sequential illumination. In this modified lane marking beam 111, all segments seg1 to seg3 are eventually illuminated. In other words, the lane marking beam 111 is ultimately illuminated in the same state as the lane marking beam 110 exemplified in Figure 5. In the illustrated example, the lane marking beam 111 is illuminated so as not to overlap with the low beam 120, but the lane marking beam 111 and the low beam 120 may be illuminated so as to partially overlap with each other.

[0046] Figure 9(B) is a timing chart showing the illumination timing of each segment in a modified lane marking enhancement beam. First, segment seg1, which is closest to the vehicle 100, is illuminated (ON), then segment seg2 is illuminated while segment seg1 remains illuminated, and finally, segment seg3 is illuminated while segments seg1 and seg2 remain illuminated. In other words, each segment seg1 to 3 starts illuminating at a different time. The illumination period for each segment seg1 to 3 can be set arbitrarily, but as an example, if the unit time is 1 frame, segment seg1 is illuminated for 3 frames, segment seg2 for 2 frames, and segment seg3 for 1 frame. After that, illumination of all segments seg1 to 3 ends (OFF). This pattern of sequential illumination of segments seg1 to 3 and then complete extinguishing may be repeated at regular intervals.

[0047] Figure 10(A) is a diagram illustrating a specific example of the modified illumination light. Figure 10(B) is a timing chart showing the illumination timing of each segment in the modified lane marking highlighting beam. In this modified lane marking highlighting beam 112, the beam is divided into eight segments seg1 to seg8 along the direction of travel of the vehicle 100, and the illumination is performed sequentially starting from segment seg1, which is closer to the vehicle 100. In detail, in this modified lane marking highlighting beam 112, segment seg1 is illuminated first, then in the next frame, segment seg2 is illuminated while the illumination of segment seg1 is maintained, and in the next frame, segment seg3 is illuminated while the illumination of segments seg1 and seg2 is maintained.

[0048] In the next frame, irradiation of segment seg1, which has been irradiated for 3 frames, is stopped, and while irradiation of segments seg2 and seg3 is maintained, segment seg4 is newly irradiated. Subsequently, with each subsequent frame, irradiation of a segment that has been irradiated for 3 frames is stopped, and the third segment from the segment whose irradiation was stopped is newly irradiated. This pattern controls the irradiation of each segment. Figure 10(B) shows the timing chart of the irradiation pattern for segments seg1 to 5. Irradiation of segments seg6 and beyond, which are not shown in the figure, is controlled in the same manner.

[0049] In this case, the lane marking reinforcement beam 112, composed of segments seg1 to 8, has a plan view shape similar to the lane marking reinforcement beam 110 described above. Furthermore, in this modified example, each segment has a gap between adjacent segments along the direction away from the vehicle. When comparing two adjacent segments, the width of each segment is set such that the segment further from the vehicle is wider. For example, comparing segments seg1 and seg2, segment seg2, which is further from the vehicle, is wider than segment seg1. Also, in this example, the plan view shape of each segment seg1 to 8 is rectangular (square). Note that the width and plan view shape characteristics of each segment are also common in the modified examples shown in Figures 11(A) and 12(A) described later.

[0050] By continuously switching the illuminated segments in this way, apparent motion can be generated, a phenomenon where something that is not actually moving appears to be moving virtually. This makes drivers and pedestrians perceive the bright spots from each segment as moving across the road surface from their vehicle towards the pedestrian. In particular, from the pedestrian's perspective, the bright spots appear to be moving towards them, making it possible to strongly alert pedestrians. As a result, it is possible to deter pedestrians from suddenly jumping out in front of vehicles.

[0051] Figure 11(A) is a diagram illustrating a specific example of the illumination light of the modified example. Figure 11(B) is a timing chart showing the irradiation timing of each segment in the lane marking enhancement beam of the modified example. This lane marking enhancement beam 113 of the modified example has multiple bright spots that change similarly to the lane marking enhancement beam 112 of the modified example described above. Specifically, in the illustrated example, there are multiple bright spots at each time, such as bright spots composed of irradiating 2 to 3 adjacent segments and bright spots composed of irradiating 1 segment, and these bright spots change continuously so that they move away from the position close to the vehicle. The same effect as described above can be obtained with such a lane marking enhancement beam.

[0052] Figure 12(A) is a diagram illustrating a specific example of the illumination light of the modified example. Figure 12(B) is a timing chart showing the irradiation timing of each segment in the modified example's border-enhancing beam. This modified example's border-enhancing beam 114 is configured such that, at one time, odd-numbered segments seg1, 3, 5, and 7 of segments seg1 to 8 are irradiated, at the next time, even-numbered segments seg2, 4, 6, and 8 of segments seg1 to 8 are irradiated, and thereafter, odd-numbered segments and even-numbered segments are irradiated alternately. Considering the transition between the two time periods, each segment is irradiated in such a way that apparent motion occurs between two adjacent segments. For example, considering the relationship between segments seg1 and seg2, apparent motion occurs between segments seg1 and seg2 as the relationship between segment seg1 being irradiated at one time and segment seg2 being irradiated at the next time is repeated. The same effect as described above can be obtained with such a border-enhancing beam.

[0053] Here, we will explain in detail the favorable conditions for apparent motion. Figure 13 is a diagram illustrating the relationship between two frames in apparent motion. Here, the first frame is referred to as "Frame 1," and the next frame as "Frame 2." The duration of each frame is defined as "Presentation Time (X)," the blackout time between Frame 1 and Frame 2 is defined as "ISI (Y)," and the on-time interval between the start of Frame 1 and the start of Frame 2 is defined as "SOA (Z)." All units are in milliseconds.

[0054] Let's assume there are two frames like this. If the frame rate (FPS), which is the number of frames per second, is greater than 20 FPS, a strong apparent motion is generated by creating a blackout period (non-illumination period) between frame 1 and frame 2. On the other hand, if the frame rate is less than 20 FPS, a strong apparent motion is generated by switching the illumination on a frame-by-frame basis. Note that this is just one example, and a blackout period may or may not be included regardless of the frame rate.

[0055] When the presentation time (X) is short (X < 100 msec), the intensity of apparent motion is mainly determined by the on-time interval SOA(Z). The optimal value for the on-time interval is 50 to 200 msec. When the presentation time (X) is long (X ≥ 100 msec), the intensity of apparent motion is mainly determined by the off-time ISI(Y). The peak value for the off-time is 0 msec.

[0056] Figure 14 illustrates the relationship between presentation time, blackout time, and on-time intervals at several frame rates. For example, when the frame rate is 10 FPS or higher but less than 20 FPS, the presentation time and blackout time for frames 1 and 2 are approximately the same length. When the frame rate is 20 FPS, the presentation times for frames 1 and 2 are the same, and the blackout time is 0 msec. When the frame rate is 40 FPS, the presentation time and blackout time for frames 1 and 2 are also approximately the same length. When the frame rate is 80 FPS, the presentation times for frames 1 and 2 are approximately the same length, and these presentation times are shorter compared to their respective blackout times.

[0057] Figures 15(A) and 15(B) show specific examples of modified illumination. As shown in Figure 15(A), in addition to the lane marking enhancement beam 110R for the lane marking located on the right side (driver's side) relative to the vehicle 100, a lane marking enhancement beam 110L located on the left side (farther from the driver's seat) relative to the vehicle 100 may also be illuminated. In this case, the lane marking enhancement beam 110R may be formed by the right headlight 9R, and the lane marking enhancement beam 110L may be formed by the left headlight 9L. Alternatively, as shown in Figure 15(B), only the lane marking enhancement beam 110L on the left side relative to the vehicle 100 may be illuminated. Although the explanation here has used a continuously illuminated lane marking enhancement beam as an example, illumination on the left side relative to the vehicle 100 may also be added in the same way for lane marking enhancement beams that are illuminated in sections.

[0058] Furthermore, in each irradiation mode of the lane marking enhancement beam, a difference in illumination may be provided between the portion directly above the lane marking and the other portions. Specifically, the portion other than the portion directly above the lane marking may be made relatively brighter. Also, the irradiation mode may be switched depending on the presence or absence of pedestrians. For example, if there are no pedestrians among the objects detected by the camera 2, etc., as an object sensor, a continuous irradiation lane marking enhancement beam may be used, and if pedestrians are present, the system may be switched to a lane marking enhancement beam that is irradiated in sections.

[0059] Furthermore, if it can be determined from the map data 6 that the vehicle is traveling on a highway, the illumination of the lane markings using the illumination modes described above may be stopped, and the system may switch to the conventional enhanced beam that selectively illuminates only the lane markings. This is because it can be determined that there are no pedestrians on the road when traveling on a highway.

[0060] Furthermore, in the embodiment in which the lane marking enhancement beam is irradiated in sections, in addition to irradiating each segment from the side closer to the vehicle and moving away from it as described above, each segment may also be irradiated from the side further away from the vehicle and moving towards it, or each segment may be irradiated to move back and forth between a position close to the vehicle and a position far away from it. In any of these cases, the irradiation of the segments in a constant pattern may be repeatedly performed. The light irradiation to each segment may be instantaneous or blinking. The size of the bright spot and the apparent movement speed may be constant or not.

[0061] Alternatively, the system may irradiate with a first beam (enhanced beam) that is irradiated in a linear, planar shape that mainly overlaps with the lane lines, and a second beam (laminated to enhance lane lines) that is irradiated in such a way that it creates apparent motion through partial irradiation as described in the above embodiment.

[0062] According to the first embodiment described above, a vehicle lighting system is provided that can improve the visibility of pedestrians and also alert pedestrians to the vehicle's presence.

[0063] (Second Embodiment) It is also preferable to set the illumination range of the lane marking enhancement beam to be variable according to the position of the oncoming vehicle. The vehicle lighting system of this second embodiment will be described below. Note that the configuration of the vehicle lighting system is the same as that of the first embodiment described above, so the explanation will be omitted here.

[0064] Figures 16(A) to 16(D) show specific examples of the emitted light in the vehicle lighting system of the second embodiment. In this embodiment, as shown in Figure 16(A), the maximum irradiable distance K of the lane marking enhancement beam is defined. This maximum irradiable distance K is a value that can be determined by assuming the vehicle speed of the vehicle 100, the pedestrian's crossing speed, the road width, etc. As a preferred example, the maximum irradiable distance K can be set to 75m. For example, on a straight road, assuming a vehicle speed of 60km / h, a pedestrian's crossing speed of 1.2m / s (assuming an elderly person), and a road width of 3.5m, and assuming a pedestrian crossing the road from the right, if the lateral distance between the center position of the vehicle 100 in the left-right direction and the pedestrian's position is 5.25m, then it takes 4.4 seconds to cross this 5.25m. The distance the vehicle travels in 4.4 seconds is approximately 73m. By adding a small margin to this value of approximately 73m, the above example value of K=75m is obtained.

[0065] In this embodiment, if an oncoming vehicle 200 is closer than the illumination limit distance described above, the illumination of the lane marking enhancement beam is stopped. This state is shown in Figures 16(A) and 16(B). This prevents glare to the oncoming vehicle 200. On the other hand, if the rear position of the oncoming vehicle 200 is closer than the position k which is the illumination limit distance K from the vehicle 100, the lane marking enhancement beam can be illuminated into the empty space to improve pedestrian visibility and draw attention to pedestrians. This state is shown in Figures 16(C) and 16(D). As can be seen by comparing the figures, the length of the lane marking enhancement beam 210 can be set to be variable according to the distance between position k and the rear position of the oncoming vehicle 200. In these cases, the lane marking enhancement beam 210 is formed by the right headlight 9R.

[0066] Figures 17(A) to 17(D) show modified examples of the illumination light in the vehicle lighting system of the second embodiment. As shown in each figure, on the right side where an oncoming vehicle 200 is present, a lane marking enhancement beam 210R, which is set to be variable in the same manner as shown in Figures 16(A) to 16(D) above, may be illuminated, while on the left side where no oncoming vehicle 200 is present, a lane marking enhancement beam 210L may be continuously illuminated. In these cases, the lane marking enhancement beam 210R is formed by the right headlight 9R, and the lane marking enhancement beam 210R is formed by the left headlight 9L.

[0067] In addition, while Figures 16(A) to 16(D) and 17(A) to 17(D) show an example of continuous irradiation for the section line enhancement beam 210 (210R, 210L), the section line enhancement beam may also be formed by sequentially irradiating partial regions in a time-division manner, as described in the first embodiment above.

[0068] Figure 18 is a flowchart showing the operation procedure of the vehicle lighting system of the second embodiment. Note that the order of the processes shown here can be changed as long as it does not result in inconsistencies or contradictions in the information processing results, and other processes not explicitly shown here can be added. This section describes additional information processing performed on the premise that the information processing according to the operation procedure shown in the vehicle lighting system of the first embodiment described above has already been executed.

[0069] The object position acquisition unit 13 of the controller 1 acquires the position of the oncoming vehicle from the camera 2 or the like, which acts as an object sensor (step S30). The glare detection unit 15 detects whether or not there is a possibility of glare occurring due to light distribution within the illumination limit distance, depending on the position of the oncoming vehicle (step S31). It is preferable to detect both the possibility of glare due to direct illumination and the possibility of glare due to specular reflection from the road surface (the same applies below).

[0070] If glare is present (step S32; YES), the illumination state setting unit 11 sets the illumination state to dim or turn off the lane marking enhancement beam. A control signal based on this set illumination state is generated by the light distribution control unit 12 and output to the right headlight 9R and the left headlight 9L, causing the lane marking enhancement beam to dim or turn off (step S33).

[0071] The object position acquisition unit 13 acquires the position of the oncoming vehicle from the camera 2, etc., which acts as an object sensor (step S34). The glare detection unit 15 compares whether the position at the limit of illumination distance or the position of the rear of the oncoming vehicle is closer to the own vehicle 100, according to the position of the oncoming vehicle (step S35).

[0072] If the rear of the oncoming vehicle is closer (step S36; YES), the glare detection unit 15 detects the presence or absence of glare due to the light distribution (step S37). The illumination state setting unit 11 sets the illumination state so that the lane marking enhancement beam is irradiated only to the rear area of ​​the oncoming vehicle, which is an area within the range determined by the illumination limit distance that does not produce glare. A control signal based on this set illumination state is generated by the light distribution control unit 12 and output to the right headlight 9R and the left headlight 9L, thereby irradiating the lane marking enhancement beam (step S38).

[0073] The object position acquisition unit 13 acquires the position of the oncoming vehicle from the camera 2, etc., which acts as an object sensor (step S39). The glare detection unit 15 compares whether the position at the limit of illumination distance or the rear position of the oncoming vehicle is closer to the vehicle 100, depending on the position of the oncoming vehicle (step S40).

[0074] If the rear of the oncoming vehicle is closer (step S41; YES), the glare detection unit 15 detects the presence or absence of glare due to the light distribution (step S42). Then, if there is no glare in the entire area within the illumination limit distance (step S43; YES), the illumination state setting unit 11 sets the illumination state so that the lane marking-enhanced beam is illuminated in the entire area within the illumination limit distance. A control signal based on this set illumination state is generated by the light distribution control unit 12 and output to the right headlight 9R and the left headlight 9L, thereby illuminating the lane marking-enhanced beam (step S44). After that, the process returns to step S30.

[0075] If there is no glare in step S32 (step S32; NO), proceed to step S44. Also, if the rear of the oncoming vehicle is further away in step S36 (step S36; NO), or if the rear of the oncoming vehicle is further away in step S41 (step S41; NO), return to step S34. If there is glare in step S43 (step S43; NO), return to step S34.

[0076] The second embodiment described above also provides a vehicle lighting system that improves pedestrian visibility and can alert pedestrians to the vehicle's presence. Furthermore, when an oncoming vehicle is present, the illumination range of the lane marking enhancement beam is variably set according to its position, thereby preventing glare to oncoming vehicles.

[0077] (Third embodiment) It is also preferable to set the illumination range of the lane marking enhancement beam to be variable according to the position of the preceding vehicle. The following describes a vehicle lighting system of such a third embodiment. Note that the configuration of the vehicle lighting system is the same as that of the first embodiment described above, so the explanation will be omitted here.

[0078] Figures 19(A) to 19(C) show specific examples of the illuminated light in the vehicle lighting system of the third embodiment. As shown in Figure 19(A), when a preceding vehicle 300 is in the same travel lane as the vehicle 100, the lane marking enhancement beams 310R and 310L are illuminated in front of the rear position of the preceding vehicle 300. Also, as shown in Figure 19(B), when the preceding vehicle 300 is located relatively to the right of the vehicle 100 (on the side where the driver's seat is located), the lane marking enhancement beam 310R is not illuminated to the right side of the vehicle 100, and the lane marking enhancement beam 310L is illuminated to the left side of the vehicle 100. Furthermore, as shown in Figure 19(C), if a preceding vehicle 300 is parked in the shoulder area to the left of the vehicle 100, the lane marking enhancement beam 310R is directed to the right of the vehicle 100, and the lane marking enhancement beam 310L is directed to an area in front of the front position of the preceding vehicle 300. These illumination methods prevent glare on the preceding vehicle 300. In either case, the lane marking enhancement beam 310R is formed by the right headlight 9R, and the lane marking enhancement beam 310R is formed by the left headlight 9L.

[0079] Figure 20 is a flowchart showing the operation procedure of the vehicle lighting system of the third embodiment. Note that the order of the processes shown here can be changed as long as it does not result in contradictions or inconsistencies in the information processing results, and other processes not explicitly shown here can be added. This section describes additional information processing performed on the premise that the information processing according to the operation procedure shown in the vehicle lighting system of the first embodiment described above has already been executed.

[0080] The object position acquisition unit 13 of the controller 1 acquires the position of the preceding vehicle from a camera 2 or the like, which acts as an object sensor (step S50). The glare detection unit 15 detects whether or not there is a possibility of glare occurring due to light distribution according to the position of the preceding vehicle (step S51). It is preferable to detect both the possibility of glare due to direct illumination and the possibility of glare due to specular reflection from the road surface (the same applies below).

[0081] If glare is present (step S52; YES), the illumination state setting unit 11 sets the illumination state to dim or turn off the lane marking enhancement beam. A control signal based on this set illumination state is generated by the light distribution control unit 12 and output to the right headlight 9R and the left headlight 9L, causing the lane marking enhancement beam to dim or turn off (step S53).

[0082] The object position acquisition unit 13 acquires the position of the preceding vehicle from the camera 2, etc., which acts as an object sensor (step S54). The glare detection unit 15 compares whether a predetermined position in front of the vehicle (for example, 40m ahead) or the position behind the preceding vehicle is closer to the vehicle 100 (step S55).

[0083] If the rear of the preceding vehicle is further away (step S56; YES), the glare detection unit 15 detects the presence or absence of glare due to the light distribution (step S57). The illumination state setting unit 11 sets the illumination state so that the lane marking enhancement beam is illuminated only in the rear area of ​​the preceding vehicle, which is an area that does not produce glare. A control signal based on this set illumination state is generated by the light distribution control unit 12 and output to the right headlight 9R and the left headlight 9L, thereby illuminating the lane marking enhancement beam (step S58).

[0084] The object position acquisition unit 13 acquires the position of the preceding vehicle from the camera 2, etc., which acts as an object sensor (step S59). The glare detection unit 15 compares whether a predetermined position in front of the vehicle or a position behind the preceding vehicle is closer to the vehicle 100, according to the position of the preceding vehicle (step S60).

[0085] If the rear position of the preceding vehicle is farther away (step S61; YES), the glare detection unit 15 detects the presence or absence of glare due to the light distribution (step S62). Then, if there is no glare in the entire area within the limit of the irradiable distance (step S63; YES), the illumination state setting unit 11 sets the illumination state so that the lane marking-enhancing beam is irradiated in the entire area within the limit of the irradiable distance. A control signal based on this set illumination state is generated by the light distribution control unit 12 and output to the right headlight 9R and the left headlight 9L, thereby irradiating the lane marking-enhancing beam (step S64). After that, the process returns to step S50.

[0086] If there is no glare in step S52 (step S52; NO), proceed to step S64. Also, if the rear of the preceding vehicle is closer in step S56 (step S56; NO), or if the rear of the preceding vehicle is closer in step S61 (step S61; NO), return to step S54. If there is glare in step S63 (step S63; NO), return to step S54.

[0087] The third embodiment described above also provides a vehicle lighting system that improves pedestrian visibility and can alert pedestrians to the vehicle's presence. Furthermore, when a preceding vehicle is present, the illumination range of the lane marking enhancement beam is variably set according to its position, thereby preventing glare on the preceding vehicle.

[0088] Furthermore, this disclosure is not limited to the contents of each embodiment described above, and can be implemented in various modified forms within the scope of the gist of this disclosure.

[0089] Examples of the features of this disclosure are listed below. (Note 1) Headlights with variable beam pattern, An object sensor configured to detect objects around the vehicle, A controller is connected to the object sensor and the headlight, respectively, and controls the operation of the headlight based on the detection result from the object sensor. Includes, The controller is configured to be able to estimate the position of at least the road markings as the object, The controller controls the headlights to project a beam in front of the vehicle, the beam having a plan view shape in which at least a portion of the beam coincides with the estimated position of the lane markings and which increases in width as it moves away from the vehicle. Vehicle lighting system. (Note 2) The controller estimates the location of the lane markings not detected by the object sensor, based at least on the detection results of the lane markings detected by the object sensor and road data corresponding to the vehicle's current position. Vehicle lighting system as described in Appendix 1. (Note 3) The plan view shape of the beam is such that the first outer edge, which is close to the lane marking, is substantially parallel to the lane marking, and the second outer edge, which is farther from the lane marking, gradually increases in distance from the lane marking as it moves away from the vehicle. Vehicle lighting systems as described in Appendix 1 or 2. (Note 4) The first outer edge of the beam is set to be located outside the vehicle relative to the optical axis of the headlight. Vehicle lighting system as described in Appendix 3. (Note 5) The beam is composed of continuously irradiated light. A vehicle lighting system as described in any of the appendices 1 to 4. (Note 6) The beam, when viewed from above, is divided into multiple sections, each of which is irradiated at a different time, until all of the sections are irradiated. A vehicle lighting system as described in any of the appendices 1 to 4. (Note 7) The plurality of portions of the beam are illuminated sequentially starting from the side closest to the vehicle, or sequentially starting from the side furthest from the vehicle, until all of the portions are illuminated. Vehicle lighting system as described in Appendix 6. (Note 8) The beam is irradiated in a time-resolved manner such that several parts of the multiple divided sections in a plan view produce apparent motion. A vehicle lighting system as described in any of the appendices 1 to 4. (Note 9) The beam's irradiation range is set to be variable according to the position of other vehicles when other vehicles are present in the vicinity of the vehicle. A vehicle lighting system as described in any of the appendices 1 to 8. (Note 10) Headlights with variable beam pattern, An object sensor configured to detect objects around the vehicle, A controller is connected to the object sensor and the headlight, respectively, and controls the operation of the headlight based on the detection result from the object sensor. Includes, The object sensor detects at least road markings as objects, The controller controls the headlights to illuminate the area overlapping with the lane markings in a plan view with a first beam and a plurality of second beams that are time-division illuminated to produce apparent motion, in front of the vehicle. Vehicle lighting system. [Explanation of Symbols]

[0090] 1: Controller, 2: Camera, 3: Millimeter-wave radar, 4: LiDAR, 5: Headlight switch, 6: Map data, 7: GPS sensor, 8: Communication unit, 9L: Left headlight, 9R: Right headlight, 11: Illumination state setting unit, 12: Light distribution control unit, 13: Object position acquisition unit, 14: Road surface condition determination unit, 15: Glare detection unit, 21: Camera, 22: Millimeter-wave radar, 23: LiDAR, 51L, 51R: ADB unit, 52L, 52R: Low beam unit, 100: Own vehicle, 110: Lane marking enhancement beam, 120: Low beam

Claims

1. Headlights with variable beam pattern, An object sensor configured to detect objects around the vehicle, A controller is connected to the object sensor and the headlight, respectively, and controls the operation of the headlight based on the detection result from the object sensor. Includes, The controller is configured to be able to estimate the position of at least the road markings as the object, The controller controls the headlights to project a beam in front of the vehicle, the beam having a plan view shape in which at least a portion of the beam coincides with the estimated position of the lane markings and which increases in width as it moves away from the vehicle. Vehicle lighting system.

2. The controller estimates the location of the lane markings not detected by the object sensor, based at least on the detection results of the lane markings detected by the object sensor and road data corresponding to the vehicle's current position. The vehicle lighting system according to claim 1.

3. The plan view shape of the beam is such that the first outer edge, which is close to the lane marking, is substantially parallel to the lane marking, and the second outer edge, which is farther from the lane marking, gradually increases in distance from the lane marking as it moves away from the vehicle. The vehicle lighting system according to claim 1.

4. The first outer edge of the beam is set to be located outside the vehicle relative to the optical axis of the headlight. The vehicle lighting system according to claim 3.

5. The beam is composed of continuously irradiated light. The vehicle lighting system according to claim 1.

6. The beam, when viewed from above, is divided into multiple sections, each of which is irradiated at a different time, until all of the sections are irradiated. The vehicle lighting system according to claim 1.

7. The plurality of portions of the beam are illuminated sequentially starting from the side closest to the vehicle, or sequentially starting from the side furthest from the vehicle, until all of the portions are illuminated. The vehicle lighting system according to claim 6.

8. The beam is irradiated in a time-resolved manner such that several parts of the multiple divided sections in a plan view produce apparent motion. The vehicle lighting system according to claim 1.

9. The beam's irradiation range is set to be variable according to the position of other vehicles when other vehicles are present in the vicinity of the vehicle. The vehicle lighting system according to claim 1.

10. Headlights with variable beam pattern, An object sensor configured to detect objects around the vehicle, A controller is connected to the object sensor and the headlight, respectively, and controls the operation of the headlight based on the detection result from the object sensor. Includes, The object sensor detects at least road markings as objects, The controller controls the headlights to illuminate the area overlapping with the lane markings in a plan view with a first beam and a plurality of second beams that are time-division illuminated to produce apparent motion, so as to illuminate the area in front of the vehicle. Vehicle lighting system.

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