Vehicle headlight assembly

Abstract

Vehicle headlight assembly (1) comprising: a headlight (6, 7) illuminating in front of a vehicle; a beam range changing device (14) for changing a beam range (21, 22) of the headlight; a detection device (2, 51) for detecting the position of a vehicle in front of the vehicle; and a control device (53) for controlling the beam range changing device based on a detection result of the detection device; wherein the vehicle headlight assembly further comprises a determination device (52) for determining whether the position of the vehicle in front is within the beam range or not, wherein the control device is configured to: • if the determination device determines that the position of the vehicle in front is within the beam range, control the beam range changing device to change the beam range accordingly,that the position of the front vehicle falls outside the illumination range, and,• if it is determined that the position of the front vehicle is outside the illumination range, not to change the illumination range or to perform a control to suppress a change in the illumination range using the illumination range change device, wherein the detection device comprises a camera (2) that captures an image in front of the vehicle, and an image processing device (51) that generates image information based on the image captured by the camera, which includes a coordinate of the front vehicle, wherein the detection device is configured to identify the position of the front vehicle by an end coordinate (D) that indicates a lateral position of one end of the front vehicle in the vehicle width direction, and wherein the determination device is configured toto make the determination based on a comparison between a reference coordinate (E), which indicates an inner boundary position of the illuminated area, and the end coordinate (D), characterized in that the determining device is configured to calculate a deviation between the reference coordinate, which indicates the inner boundary position of the illuminated area, and the end coordinate and to make the determination based on this deviation, and in that the control device is further configured to: • if the reference coordinate deviates from the end coordinate to a first side in the vehicle width direction, such that the end coordinate lies within the illuminated area, control the illuminated area changing device so that it changes the illuminated area to bring the reference coordinate into agreement with the end coordinate, and • if the reference coordinate deviates from the end coordinate to a second side,which is opposite to the first side in the direction of vehicle width, and the deviation calculated by the determining device is greater than or equal to a predetermined value, to calculate a target coordinate which internally divides the end coordinate and the reference coordinate in a predetermined ratio, and to control the lighting range change device so that it changes the lighting range in order to bring the reference coordinate into agreement with the target coordinate.

Description

TECHNICAL FIELDThe present invention relates to vehicle headlamp devices.PRIOR ARTIn the related art, adaptive headlight systems (AFSs) are known that control the directions of optical axes of headlights according to the steering direction, thereby improving the safety of the vehicle during night driving.In addition, high beam variable headlight systems (or adaptive headlight systems) utilizing a light distribution pattern referred to as "intermediate headlight" are known. This light distribution pattern shields a part corresponding to a front vehicle (a preceding vehicle or an oncoming vehicle), while other parts are illuminated with high beam. Such systems further detect the position of the front vehicle by image processing information from a vehicle camera and trace the hidden area to the front vehicle, thereby ensuring a wide forward range of vision and making it easy to recognize pedestrians without dazzling a driver of a front vehicle.Moreover, JP 2012-020 715 A discloses a vehicle headlight device that calculates coordinate information about a preceding vehicle based on information captured by a camera, and turns the headlights to the left or right with an actuator to move the lighting range, whereby the shaded range follows the preceding vehicle.A system for controlling the light distribution of vehicle headlights is also known from EP 2 266 837 B1. At this time, a controller detects a preceding vehicle which is in front of the own vehicle, and selects one light distribution pattern from the plurality of light distribution patterns based on the result of the detection, and controls the vehicle headlights to emit the selected light distribution pattern. When a light distribution pattern having a wider emission range in the front view of the driver is switched over as before, the control means sets a "determination time" of a preceding vehicle to be set larger than that when a light distribution pattern having a narrower emission range in the front view of the driver is switched over, the "determination time" being defined as a time elapsed between the occurrence of a change in the determination result of a preceding vehicle and the start of the switching of a light distribution pattern, and the control means changes the "determination time" of a preceding vehicle according to the horizontal position of the preceding vehicle.SUMMARY OF THE INVENTIONProblem to be Solved by the InventionHowever, when the vehicle headlamp apparatus disclosed in JP 2012-020 715 A is evaluated in a state mounted on a vehicle, it has become clear that it sometimes feels annoying. For example, a preceding vehicle moves regardless of intention of a driver of a following vehicle; therefore, when the preceding vehicle frequently performs steering motion, a annoying feeling arises when the illuminance of the headlights of the own vehicle minutely follows the motion of the preceding vehicle.Further, when a reflecting wall is in the vicinity of the front vehicle, the reflecting wall may be erroneously recognized as the front vehicle. In this case, in order to turn the lamp width or the lamp area away from the reflecting wall, the headlights are swung in a direction away from the front vehicle. However, since the reflecting wall softening from the illuminated area does not reflect light, the headlights are swung again to approach them to the front vehicle. Then, the reflecting wall reflects light again, and the headlights are swung in a direction away from the front vehicle again to turn the lamp width and the lamp area away from the reflecting wall, respectively. Consequently, a hunting phenomenon occurs in which the above processes are repeated; this is annoying.Besides, as compared with the low beam, the intermediate high beam illuminates not only a far area but also a near area brightly. Therefore, the movement of the light area, the trees standing at the road edge, and noise walls are easily recognized, which is annoying.Although this annoying perception of such problems varies from individual to individual, some may therefore not concentrate or become tired. It is therefore desired to execute control so that the driver is not disturbed by such problems.The present invention has been made in light of the above-described problems. Therefore, it is an object of the present invention to provide a vehicle headlamp apparatus that does not blind a driver or occupant of a preceding vehicle and does not interfere with a driver of an own vehicle.Means for Solving the ProblemAccording to the invention set forth in claim 1, achieving the above-described object, a vehicular headlamp apparatus comprises: a headlamp which illuminates in front of a vehicle; illumination area changing means for changing an illumination area of the headlamp; detecting means for detecting a position of a front vehicle located in front of the vehicle; and control means for controlling the illumination area changing means based on a detection result of the detecting means. The vehicle headlamp apparatus further comprises: determination means for determining whether or not the position of the front vehicle is within the lighting range. The control means is configured to: when it is determined by the determination means that the position of the front vehicle is within the lighting range, control the lighting range changing means to change the lighting range such that the position of the front vehicle falls outside the lighting range, and when it is determined that the position of the front vehicle is outside the lighting range, not change the lighting range, or execute control for suppressing change in the lighting range with the lighting range changing means.In the above-described configuration, when it is determined that the position of the front vehicle is within the lighting range of the headlights, the control means controls the lighting range changing means to change the lighting range such that the position of the front vehicle falls outside the lighting range. Consequently, the driver or an occupant of the front vehicle is not blinded. In addition, when it is determined that the position of the front vehicle is outside the lighting range, the controller does not change the lighting range or performs control for suppressing a change in the lighting range with the lighting range changing device. Consequently, the driver of the own vehicle does not feel disturbed by the frequent movement of the lighting area.The detection means includes a camera that captures an image in front of the vehicle and an image processing means that generates image information including a coordinate of the front vehicle based on the image captured by the camera; the detection means is configured to identify the position of the front vehicle by an end coordinate indicating a lateral position of an end of the front vehicle in the vehicle width direction; the determination means is configured to make the determination based on a comparison between a reference coordinate indicating an inner limit position of the lighting range and the end coordinate.In the above-described configuration, the acquisition device generates, based on images captured in front of the vehicle, the image information with the coordinate of the front vehicle, and identifies the position of the front vehicle by an end coordinate indicating a lateral position of an end of the front vehicle in the vehicle width direction. Consequently, it is possible to accurately grasp the front vehicle within a short time. Moreover, the determination means makes the determination based on a comparison between the reference coordinate indicating an inner limit position of the lighting range and the end coordinate; when it is determined by the determination means that the position of the front vehicle is within the lighting range, the control means controls the lighting range changing means to change the lighting range to match the reference coordinate with the end coordinate. Consequently, it is possible to move the lighting area to the proper location.The determination device is configured to calculate a deviation between the reference coordinate indicating the inner boundary position of the lighting region and the end coordinate, and make the determination on the basis of this deviation. With this configuration, it is possible for the control means to independently control the lighting range changing means when the deviation is large and when the deviation is small. Consequently, it is possible to appropriately set the lighting range according to the respective cases.The control means is further configured to: when the reference coordinate deviates from the end coordinate to a first side in the vehicle width direction so that the end coordinate is within the lighting range, control the lighting range changing means to change the lighting range to match the reference coordinate with the end coordinate, and when the reference coordinate deviates from the end coordinate to a second side opposite to the first side in the vehicle width direction and the deviation calculated by the determination means is greater than or equal to a predetermined value, calculate a target coordinate internally sharing the end coordinate and the reference coordinate at a predetermined ratio, and control the lighting range changing means to change the lighting range to match the reference coordinate with the target coordinate.A further vehicle headlight device for achieving the object described at the beginning is the subject matter of claim 3.BRIEF DESCRIPTION OF THE DRAWINGSFIG. 1 is a functional block diagram illustrating the overall configuration of a vehicle headlamp device according to an embodiment; FIG. 2 is a schematic view showing the structure of a headlamp; FIG. 3 is a schematic view of the light distribution pattern in the intermediate remote light as viewed from above; FIG. 4 is a schematic view of the light distribution pattern in the intermediate remote light as viewed from a driver's seat; FIG. 5 is a flowchart showing a process of an ECU (Electronic Control Unit) for controlling the lighting range of the headlamp; FIG. 6 is a schematic view showing the case where the illumination range of the headlamp overlaps the preceding vehicle; FIG. 7 is a schematic view showing the case where the lighting range of the headlamp is deviated by a predetermined angle or more from the preceding vehicle; and FIG. 8 is a schematic view showing the case where the illumination range of the headlamp is deviated by less than the predetermined angle from the preceding vehicle.EMBODIMENTS OF THE INVENTIONNext, a vehicle headlamp apparatus 1 according to an embodiment of the present invention will be described with reference to FIGS. 1 to 8. As shown in FIG. 1, the vehicle headlamp apparatus 1 includes a vehicle camera 2, a steering angle sensor 3, a wheel speed sensor 4, an ECU (Electronic Control Unit) 5, and headlamps 6 and 7.The in-vehicle camera 2 is disposed within a front windshield of a vehicle. The in-vehicle camera 2 captures an image in front of the vehicle and transmits the data to the ECU 5. The steering angle sensor 3 is an existing sensor for an ESC (Electronic Stability Program) disposed in a steering mechanism. The steering angle sensor 3 detects a steering angle of the vehicle and sends a steering angle signal indicative of the detection results to the ECU 5. The wheel speed sensor 4 is an existing sensor provided for use in an ABS (Anti-lock Brake System). The wheel speed sensor 4 detects a rotational speed of a wheel of the vehicle and sends a wheel speed signal indicating the detection results to the ECU 5.The ECU 5 is a control unit for controlling the headlights 6 and 7. specifically, the ECU 5 has an image processing part 51, a determination part 52, and a control part 53. the image processing part 51 performs image processing on the data of the in-vehicle camera 2, and calculates the position of a front vehicle (a preceding vehicle or an oncoming vehicle) in the form of coordinates. The determination part 52 determines the direction and the amount of the deviation between the position of the front vehicle and the lighting ranges of the headlights. The control part 53 instructs the headlights 6 and 7 to switch light distribution patterns and perform panning. Moreover, based on the steering angle signal output from the steering angle sensor 3 and the wheel speed signal output from the wheel speed sensor 4, the control part 53 may command the headlights 6 and 7 to perform a swivel motion as in a conventional AFS.The headlights 6 and 7 are a pair of headlights mounted to the left and right of the vehicle, respectively, to illuminate in front of the vehicle. As shown in FIG. 2, each of the headlights 6 and 7 includes a light source 11, a lens 12, a shutter mechanism 13, and an actuator 14. The shutter mechanism 13 includes a plurality of shutter plates, not shown. The shade mechanism 13 forms an intermediate high beam pattern and a low beam pattern according to a command from the control part 53 of the ECU 5 by being inserted into a part of the optical path formed in the headlight to block the light. Moreover, the shade mechanism 13 forms a high beam pattern by being completely retracted from the optical path. The headlights 6 and 7 also have these three light distribution patterns.As illustrated in FIGS. 3 and 4, the intermediate remote light is a concave light distribution pattern that shields a part corresponding to the front vehicle so as not to shield an occupant of the front vehicle. The left headlight defines a lighting area 21 having a substantially L-shaped light distribution pattern. The right headlight defines a lighting region 22 which has a substantially mirror-inverted L-shaped light distribution pattern.When the left and right headlights simultaneously constitute the intermediate remote light, a light distribution pattern as shown in FIGS. 3 and 4 is obtained. Ideally, as illustrated in FIG. 4, it is preferable that the lighting regions are arranged such that positions at left and right ends of the front vehicle coincide with positions of vertical cut lines of the lighting regions. Therefore, the position of the front vehicle is always checked and the headlights are turned.The intermediate high beam light has the same brightness as the high beam, except for the shaded area. Therefore, if the intermediate remote light were to inadvertently illuminate the front vehicle and the front vehicle were an oncoming vehicle, the light would directly enter the eyes of the driver of the oncoming vehicle to blind the driver. If the front vehicle were a preceding vehicle, the mirror reflected light would enter the eyes of the driver of the preceding vehicle and / or light up the passenger compartment of the preceding vehicle, making it difficult to grasp the external environment. Therefore, in order to avoid the above, when the light distribution pattern of the headlights is switched from the high beam or the low beam to the intermediate high beam, it is necessary to calculate the rotation angles.Moreover, the actual light distribution pattern is not left-right symmetrical, but the left side is illuminated more. However, this is irrelevant to the explanation of the present invention. For convenience, therefore, explanation will be made on the assumption that the light distribution pattern is symmetrical in each figure.Moreover, the headlights 6 and 7 may be switched to the high beam, the low beam, or an ADB mode by a manual switch. ADB (adaptive headlight) refers here to a variable headlight remote light system. The ADB mode is an automatic switching mode in which the control part 53 of the ECU 5 automatically switches the left and right headlights to the high beam or individually switches the left and right headlights to the intermediate high beam or low beam.Specifically, in the ADB mode, the control part 53 of the ECU 5 switches the left and right headlights to the high beam when there is no vehicle front. When a front vehicle exists, the control part 53 of the ECU 5 switches the left and right headlights to the intermediate headlight.Further, when the preceding vehicle makes a left turn and the swivel angle of the left headlight thus becomes larger than a predetermined angle, the control part 53 of the ECU 5 switches the left headlight to the low beam. At this time, the right headlight is held in the intermediate high beam. In addition, when the front vehicle is an oncoming vehicle that travels in another direction and the own vehicle approaches the oncoming vehicle, the control part 53 of the ECU 5 keeps the left headlight in the intermediate high beam and turns only the right headlight to the low beam when the swivel angle of the right headlight becomes larger than the predetermined angle.At the position where the diaphragm mechanism 13 inserts and removes the diaphragms as shown in FIG. 2, the up-down and left-right relationship is reversed by the lens 12. Thus, when the shutter mechanism 13 covers the lower side of the optical path as shown in FIG. 2, the upper side of the lighting area is blanked out. That is, by covering a predetermined lower portion of the optical path, it is possible to realize a light distribution pattern shown in Figs. 3 and 4.The actuator 14 controls the entire headlamp to rotate about a rotation axis according to a command from the control part 53 of the ECU 5. In the present embodiment, when the light distribution pattern of the headlamp is the low beam or the high beam, the actuator 14 controls the headlamp based on the steering angle as in a conventional AFS. In the ADB mode, the actuator 14 controls the headlamp to swing the lighting range based on the data of the in-vehicle camera 2 and corresponding to the position of the front vehicle only when the light distribution pattern of the headlamp is the intermediate high beam.Next, the control and operation of the vehicle headlamp device 1 according to the present embodiment will be described. The flowchart shown in FIG. 5 illustrates a process of the ECU 5 executed when the headlights are placed in the ADB mode and switched to the intermediate headlight. The initialization of the data and the initialization process such as a mode determination process are omitted. The "START" in FIG. 5 denotes a state in which these initialization processes have already been completed.Moreover, hereinafter, for convenience, the description will be made only with respect to the right end of a preceding vehicle. The process according to the present embodiment can be similarly applied also to the left end of the preceding vehicle and both ends of an oncoming vehicle.The position E of the vertical line of intersection of the substantially inverted L-shaped light distribution pattern of the right headlight shown in FIG. 4 is defined as the reference coordinate of the lighting region 22. The reference coordinate is determined based on the command information from the control part 53 of the ECU 5 to the actuator 14 of the headlamp. In FIGS. 6 to 8, the right end coordinate of the preceding vehicle is denoted by D, and the reference coordinate of the lighting area 22 is denoted by E.First, it is detected whether a front vehicle exists (step S1, hereinafter abbreviated as S-1; other steps are similarly abbreviated), then the right end coordinate of the preceding vehicle is calculated (S-2). The right end coordinate is determined based on image processing of the information of the in-vehicle camera 2 in the image processing part 51 of the ECU 5 and detection of, for example, a pair of red tail lamps.Then, the deviation between the reference coordinate E of the illumination area 22 and the right end coordinate D of the preceding vehicle is calculated, which is regarded as the deviation from the ideal state (right end coordinate=reference coordinate) (S- 3).The right side of FIG. 6 is the positive direction of the coordinate, and the left side is the negative direction. Accordingly, when the lighting area 22 illuminates the preceding vehicle as shown in FIG. 6, the deviation calculated by the equation (1) is positive (S-4: YES).In this case, a filter constant is set to A (S-5). The filter constant A is, for example, 1.0. Using the filter constant A enables calculation of a target coordinate to which the reference coordinate needs to be moved in the following equation (2).Since the filter constant A in S-5 has been set to 1.0, the result of the calculation of Equation (2) is as follows.When the right end of the preceding vehicle enters the lighting area 22 and the headlamp thus illuminates the preceding vehicle, the headlamp is driven to move the reference coordinate of the lighting area to the right end of the preceding vehicle (S-7). Consequently, the reference coordinate becomes equal to the target coordinate (S-8). At the same time, by equation (3), the right end coordinate becomes equal to the reference coordinate. As a result, as shown in FIG. 4, the right vehicle end coincides with the cut line of the lighting area 22. In addition, the target coordinate of Equation (3) is a coordinate that sets the deviation determined in S-3 to zero. Subsequently, a counter for another process described later is reset (S-9), and the process returns to START. Then, the flow is executed again starting from the vehicle detection (S-1).Practically, when the lighting area 22 illuminates the preceding vehicle as shown in FIG. 6, the light reflected by mirrors shines into the eyes of the driver of the preceding vehicle and / or illuminates the passenger compartment of the preceding vehicle brightly, making it difficult to grasp the environment. It is therefore necessary to move the lighting area directly.In the case of (S-4: NO)The following describes the case where the deviation calculated in Equation (1) is negative. When the lighting range deviates from the right end of the preceding vehicle as shown in FIG. 7, the deviation calculated in Equation (1) is negative (S- 4: NO). In this case, a predetermined value X is given and the deviation is compared with the predetermined value X. The predetermined value X is here, for example, -1°. Then, when the deviation is smaller than -1°, that is, when the lighting area 22 deviates from the right end of the preceding vehicle by more than 1° absolute value (S-10: YES), the filter constant is set to B (S-11). The filter constant B is, for example, 0.5. Using the filter constant B, the target coordinate to which the reference coordinate is to be moved is calculated in Equation (2), the result of which is as follows.That is, the target coordinate is a coordinate internally sharing the right end coordinate and the reference coordinate with a ratio of 1:1, in other words, is the average value of the right end coordinate and the reference coordinate.Thus, when the lighting range 22 deviates from the preceding vehicle to the right by more than the predetermined value, the headlamp is driven to bisect the deviation between the right end coordinate of the preceding vehicle and the reference coordinate of the lighting range 22 (S-7). As a result of the movement, the reference coordinate is moved to the target coordinate (S-8). In addition, the target coordinate determined by equation (4) is a coordinate that bisects the deviation determined in S-3. Subsequently, a counter for another process, which will be described later, is reset (S-9), and the process returns to START. Then, the flow is executed again starting from the vehicle detection (S-1).In the case of (S-4: NO) and (S-10: NO)The following describes the case where the deviation is larger (or smaller in absolute value) than the predetermined value X. When the deviation is larger than -1°, that is, when the lighting range 22 deviates from the right end of the preceding vehicle by 0° to 1° in absolute value (S-10: NO), the value of the counter is compared with a predetermined value Z (S-20). Here, the predetermined value Z is 5. When the value of the counter is less than or equal to 5 (S- 20: NO), the counter is incremented (S- 30), and the process returns to S- 1. Therefore, unless the positional relationship between the own vehicle and the preceding vehicle is changed, the loop S-30→S-1 is repeated. For the period in which the loop is repeated 5 times (e.g., 1 second per repetition × 5 repetitions = 5 seconds), the reference coordinate is maintained and the headlamp is not driven. In addition, when the positional relationship between the own vehicle and the preceding vehicle is changed, a new right end coordinate is obtained in S- 2 in the next loop, and the process according to this condition is executed without waiting for 5 seconds.If the value of the counter is larger than 5 (S-20: YES), the filter constant is set to C (S-21). The filter constant C is, for example, 0.1. Using the filter constant C, the target coordinate to which the reference coordinate is to be moved is calculated by Equation (2), and the result is as follows.That is, the target coordinate is a position that divides the interval between the right end coordinate and the reference coordinate at a ratio of 9:1. Thus, when the lighting area 22 deviates rightward from the preceding vehicle by the predetermined value X or less, the headlamp is driven to guide the reference coordinate of the lighting area 22 closer to the right end of the preceding vehicle by 10% (S- 7). As a result of this movement, the reference coordinate is moved to the target coordinate (S-8). In addition, the target coordinate determined by Equation (5) is a coordinate that reduces the deviation determined in S-3 to 90%. Subsequently, the counter for S-20 is reset (S-9), and the process returns to START. Then, the flow is executed again starting from the vehicle detection (S-1).Assuming that the position of the preceding vehicle continuously satisfies the condition S-10 equal to NO for more than 10 seconds, S-21 and subsequent steps are executed at least twice, whereby the reference coordinate moved to the target coordinate according to the above-mentioned S-7 is moved by more than 10%. In addition, compared with the reference coordinate before the twice movement, the total amount of movement becomes 19 % (i.e., 1-0.9×0.9).As described above, by repeating S-21 and the subsequent steps, the reference coordinate is gradually approximated to the right end coordinate. Practically, this means that it is rare that the positional relationship with the preceding vehicle remains unchanged for more than 10 seconds. Rather, the positional relationship changes at all times, so that the process is executed such that the right end coordinate is newly acquired in S- 2.Consequently, it is possible to avoid the disturbance due to the missense. For example, when a reflective wall is in the vicinity of the preceding vehicle and the reflective wall is visible from the following vehicle, as a result of the image processing of the information of the in-vehicle camera 2, the light of the reflective wall may be erroneously captured as that of tail lamps of the preceding vehicle. In this case, S- 4 becomes YES, and the target coordinate is moved to an end of the reflecting wall. Then, the light can no longer reach the reflecting wall and the tail lamp of the preceding vehicle is correctly recognized. However, S-10 becomes NO and the reference coordinate is maintained. Consequently, it is possible to avoid the occurrence of a hunting phenomenon in which the light repeatedly reaches and does not reach the reflecting wall, and the reference coordinate of the lighting area is repeatedly moved between the reflecting wall and the end of the preceding vehicle.The above cases where the deviation calculated in Equation (1) is negative are summarized here. In the case where the right end position of the preceding vehicle deviates from the lighting area 22 and the deviation in absolute value is less than or equal to the predetermined value, when the condition continues for 5 seconds, the reference coordinate is maintained, and the headlamp is not driven. Subsequently, the lighting area 22 is moved closer to the preceding vehicle by 10%. Moreover, when the right end position of the preceding vehicle deviates from the lighting range 22 and the deviation is larger in absolute value than the predetermined value, the headlamp is turned so that the target coordinate is moved closer to the preceding vehicle by 50% of the deviation.Practically, when the lighting range 22 deviates from the preceding vehicle as illustrated in FIGS. 7 and 8, there is no concern that the light of the headlamp may blind the driver of the preceding vehicle. Consequently, it is not necessary to make the reference coordinate of the lighting area 22 immediately coincide with the right end coordinate of the preceding vehicle. Therefore, the lighting area is moved either after waiting a certain time or moved by 50% of the deviation.As is clear from the above explanations, a vehicle headlamp apparatus (1) according to the present embodiment includes: a headlamp (6, 7) that illuminates in front of a vehicle; illumination area changing means (actuator 14) for changing the illumination area (21, 22) of the headlamp; detecting means (the in-vehicle camera 2 and the image processing part 51) for detecting a position of a front vehicle located in front of the vehicle; and control means (the control part 53) for controlling the illumination area changing means based on the position of the front vehicle detected by the detecting means. The apparatus further includes determination means (the determination part 52) for determining whether or not the position of the front vehicle is within the lighting range. When it is determined by the determination means that the position of the front vehicle is within the lighting range, the control means controls the lighting range changing means to change the lighting range so that the position of the front vehicle falls outside the lighting range. When the position of the preceding vehicle is determined to be out of the range of illumination, the control means does not change the illumination range or performs control for suppressing a change in the illumination range with the illumination range changing means.Moreover, the detection device according to the present embodiment includes the in-vehicle camera 2 that captures an image in front of the vehicle and the image processing device (the image processing part 51) that processes image information having a coordinate of the preceding vehicle based on the images captured by the camera 2. The detecting means identifies the position of the preceding vehicle by an end coordinate indicating the lateral position of an end of the preceding vehicle in the vehicle width direction. The determination means (the determination part 52) performs the determination based on a comparison between the reference coordinate indicating an inner boundary position of the lighting area and the end coordinate. When the position of the preceding vehicle is determined to be in the lighting range by the determination means, the control means (the control part 53) controls the lighting range changing means to change the lighting range so as to make the reference coordinate coincide with the end coordinate.Moreover, according to the present embodiment, the determination means (the determination part 52) calculates a deviation between the reference coordinate indicating the inner limit position of the lighting area 21, 22 and the end coordinate, and performs the determination based on this deviation.Moreover, according to the present embodiment, when the deviation calculated by the determination means (the determination part 52) is greater than or equal to a predetermined value, the control means (the control part 53) calculates a target coordinate internally dividing the end coordinate and the reference coordinate at a predetermined ratio (first predetermined ratio), and controls the lighting range changing means (actuator 14) to change the lighting range 21, 22 so as to bring the reference coordinate into agreement with the target coordinate. When the deviation calculated by the determination means (the determination part 52) is less than the predetermined value, the control means does not change the lighting area 21, 22 for a predetermined period of time for which this state continues. After the lapse of the predetermined time, the control means calculates a target coordinate internally dividing the end coordinate and the reference coordinate at another predetermined ratio (second predetermined ratio) different from the first predetermined ratio, and controls the lighting range changing means (the actuator 14) to change the lighting range 21, 22 to bring the reference coordinate into agreement with the target coordinate.[Modification]According to the above-described embodiment, the deviation between the right end coordinate of the preceding vehicle and the reference coordinate is compared with the predetermined value X, and the process is varied according to the result of the comparison. However, it is possible to execute the process in another manner regardless of the amount of deviation.That is, regardless of the amount of the deviation, the controller (the controller 53) may calculate a target coordinate internally sharing the right end coordinate and the reference coordinate in the ratio of, for example, 1:1, and then control the lighting range changer (the actuator 14) to change the lighting range 21, 22 so as to match the reference coordinate with the target coordinate.According to the above configuration, even if the deviation is greater than or equal to the predetermined value, the lighting range is not immediately matched with the vehicle end; instead, the lighting range is changed to half the deviation. By repeating this process without performing a large operation, the position detection is performed again, and a target coordinate to which the lighting range is to be changed is calculated again based on the new deviation. Consequently, even in a case where the relative position to the front vehicle changes leftward or rightward within a short time, it becomes possible to reduce the movement of the lighting area and thereby avoid a annoying feeling.Alternatively, regardless of the amount of the deviation, the controller (the control part 53) may not change the lighting area 21, 22 for the predetermined time. After the lapse of the predetermined time, the control means may calculate a target coordinate internally sharing the end coordinate and the reference coordinate in a ratio of, for example, 9:1, and then control the lighting range changing means (the actuator 14) to change the lighting range 21, 22 to match the reference coordinate with the target coordinate.According to the above configuration, when the position of the preceding vehicle is outside the lighting range, the lighting range is not changed for a predetermined period of time within which the state continues. Therefore, frequent movement of the lighting portion is avoided, so that no uncomfortable feeling occurs. Moreover, after the lapse of the predetermined time, the lighting range is changed to reduce the deviation to 90%. By repeating this process, it appears as if the lighting area gradually approaches the preceding vehicle. Consequently, it is possible to minimize the state that the driver of the own vehicle feels uncomfortable due to the frequent movement of the lighting area.Moreover, the present invention is not limited to the above-described embodiment and its modifications. It is to be understood that various changes may be made without departing from the spirit of the present invention.For example, the explanation of the present embodiment is based on a preceding vehicle. However, by configuring the in-vehicle camera 2 to detect the lights of headlights of an oncoming vehicle, it is also possible to similarly detect left and right ends of an oncoming vehicle and apply the control of the above-described embodiment.Moreover, the camera 2 may be realized by an existing camera used for other purposes, for example, a collision avoidance system.In the above-described embodiment, the filter constant B is 0.5 and the filter constant C is 0.1. The target coordinate is calculated by equation (2).In the above embodiment, the light sources of the headlights are halogen lamps. However, the light sources of the headlights may also be realized by LED lamps, HID lamps (HID is a registered trademark), or other types of light sources.In the above-described embodiment, the reference coordinate is determined based on command information from the ECU 5 to the actuators 14 of the headlights 6 and 7. However, the reference coordinate may be determined by image processing the information of the in-vehicle camera 2 with the aid of the command information to the actuators 14.The above-described embodiment is based on the assumption that the vehicle is traveling on the left as in Japan and United Kingdom. However, the invention can be similarly applied to vehicles traveling on the right side.LIST OF REFERENCE CHARACTERS1 Vehicle headlight device 2 Vehicle camera 5 ECU 6, 7 Headlight 13 Shutter mechanism 14 Actuator 21, 22 Lighting regions 52 Determination part 53 Control part

Claims

A vehicular headlamp apparatus (1) comprising: a headlamp (6, 7) that illuminates in front of a vehicle; an illuminated area changing means (14) for changing an illuminated area (21, 22) of the headlamp; a detecting means (2, 51) for detecting a position of a front vehicle located in front of the vehicle; and a control means (53) for controlling the illuminated area changing means based on a detection result of the detecting means; wherein the vehicular headlamp apparatus further comprises a determining means (52) for determining whether or not the position of the front vehicle is within the illuminated area, wherein the control means is configured to: • when it is determined by the determining means that the position of the front vehicle is within the illuminated area, control the illuminated area changing means to change the illuminated area in such a manner, wherein the position of the front vehicle falls outside the lighting range, and • when it is determined that the position of the front vehicle is outside the lighting range, not to change the lighting range or to perform, with the lighting range changing means, control for suppressing a change in the lighting range, wherein the detecting means includes a camera (2) that captures an image in front of the vehicle and an image processing means (51) that generates, based on the image captured by the camera, image information including a coordinate of the front vehicle, wherein the detecting means is configured to identify the position of the front vehicle by an end coordinate (D) indicating a lateral position of an end of the front vehicle in the vehicle width direction, and wherein the determining means is configured to determine based on a comparison between a reference coordinate (E), which indicates an inner boundary position of the lighting area and makes the end coordinate (D), characterized in that the determination means is configured to calculate a deviation between the reference coordinate which indicates the inner boundary position of the lighting area and the end coordinate and to make the determination based on this deviation, and in that the control means is further configured to: • when the reference coordinate deviates from the end coordinate to a first side in the vehicle width direction such that the end coordinate is within the lighting area, control the lighting area changing means to change the lighting area to match the reference coordinate with the end coordinate, and • when the reference coordinate deviates from the end coordinate to a second side which is opposite to the first side in the vehicle width direction, and the deviation calculated by the determining means is greater than or equal to a predetermined value, calculate a target coordinate internally sharing the end coordinate and the reference coordinate at a predetermined ratio, and control the lighting range changing means to change the lighting range to bring the reference coordinate into agreement with the target coordinate.The vehicle headlamp apparatus according to claim 1, further characterized in that the control means is configured to, when the reference coordinate deviates from the end coordinate to the second side in the vehicle width direction and the deviation calculated by the determination means is less than the predetermined value, not change the lighting range for a predetermined period during which this state continues, and the control means is configured to, after elapse of the predetermined period, calculate a target coordinate that internally divides the end coordinate and the reference coordinate at a second predetermined ratio different from the predetermined ratio, and control the lighting range changing means to change the lighting range to match the reference coordinate with the target coordinate.A vehicular headlamp apparatus (1) comprising: a headlamp (6, 7) that illuminates in front of a vehicle; an illuminated area changing means (14) for changing an illuminated area (21, 22) of the headlamp; a detecting means (2, 51) for detecting a position of a front vehicle located in front of the vehicle; and a control means (53) for controlling the illuminated area changing means based on a detection result of the detecting means; wherein the vehicular headlamp apparatus further comprises: a determining means (52) for determining whether or not the position of the front vehicle is within the illuminated area, wherein the control means is configured to: • when it is determined by the determining means that the position of the front vehicle is within the illuminated area, control the illuminated area changing means to change the illuminated area such that, wherein the position of the front vehicle falls outside the lighting range, and • when it is determined that the position of the front vehicle is outside the lighting range, not to change the lighting range or to perform, with the lighting range changing means, control for suppressing a change in the lighting range, wherein the detecting means includes a camera (2) that captures an image in front of the vehicle, and an image processing means (51) that generates, based on the image captured by the camera, image information including a coordinate of the front vehicle, wherein the detecting means is configured to identify the position of the front vehicle by an end coordinate (D) indicating a lateral position of an end of the front vehicle in the vehicle width direction, wherein the determining means is configured to determine based on a comparison between a reference coordinate (E), which indicates an inner boundary position of the lighting area and to meet the end coordinate (D) when it is determined by the determining means that the position of the front vehicle is within the lighting area, the control means controls the lighting area changing means to change the lighting area to bring the reference coordinate into agreement with the end coordinate; and characterized in that the determining means is configured to calculate a deviation between the reference coordinate indicating the inner boundary position of the lighting area and the end coordinate and to meet the determination based on this deviation, and in that the control means is further configured to: • when the reference coordinate deviates from the end coordinate to a first side in the vehicle width direction such that the end coordinate is within the lighting area, the lighting area changing means is controlled to change the lighting area so as to make the reference coordinate coincide with the end coordinate, • when the reference coordinate deviates from the end coordinate to a second side opposite to the first side in the vehicle width direction and the deviation calculated by the determining means is less than a predetermined value, not to change the lighting area for a predetermined period during which this state continues, and • after the lapse of the predetermined period, to calculate a target coordinate internally sharing the end coordinate and the reference coordinate at a predetermined ratio, and to control the lighting area changing means to change the lighting area so as to make the reference coordinate coincide with the target coordinate.

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