JP2016179781A - Lighting controller of vehicular headlight and vehicular headlight system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light distribution technology which can alleviate discomfort to a driver and the like upon switching a light irradiation state.SOLUTION: A lighting controller of a vehicular headlight system capable of individually irradiating each segment with light comprises a vehicle detection part 11 that detects a position of a vehicle ahead, a light irradiation range setting part 13 that sets a light irradiation range and a non-irradiation range in accordance with the position of the vehicle ahead, a switching segment determination part 14 that determines whether or not a plurality of switching object segments switchable to a lighting state corresponding to a light irradiation range with changes in position of the non-irradiation range, out of segments being in an extinguished state in accordance with the non-irradiation range in each segment, a movement direction judgment part 15, a lighting timing setting part 16, and a lighting control part 17 that feeds light distribution control signals for individually lighting and extinguishing each segment.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a lighting control technology for a vehicle headlamp that performs selective light irradiation according to the position of a vehicle ahead.

  There is known a light distribution control technique for detecting a preceding vehicle (an oncoming vehicle or a preceding vehicle) and irradiating light to the other region without irradiating the region where the preceding vehicle exists (for example, Patent Document 1). In many cases, in this light distribution control, the position of the front vehicle is detected by performing a predetermined image recognition process on an image obtained by photographing the front of the host vehicle with a camera installed in the host vehicle. For example, the position of the vehicle ahead is specified by the positions of the left and right headlamps in the case of an oncoming vehicle, and is specified by the positions of the left and right tail lights in the case of a preceding vehicle. By performing such light distribution control, it is possible to prevent glare from being given to the preceding vehicle and to improve the visibility of the area where the preceding vehicle does not exist.

  By the way, in said light distribution control, the position of the vehicle ahead is detected for every predetermined time, and the range (non-irradiation range) which does not irradiate light according to it is set, and according to this non-irradiation range, horizontal direction, for example Whether or not to irradiate light is determined for each of the plurality of segments (divided regions) arranged in (1). The light irradiation / non-irradiation in each of these segments fluctuates every moment according to the situation of the preceding vehicle. For example, when the preceding vehicle moves to the left or right, the non-irradiation range moves according to the moving direction. At this time, when the segment that was not subject to light irradiation is switched to the subject of light irradiation due to the fluctuation of the non-irradiation range, the segment suddenly switches from the dark state to the bright state. For this reason, the driver may feel uncomfortable. Such inconvenience becomes more prominent as the movement of the preceding vehicle increases.

JP 2013-79044 A

  A specific aspect of the present invention is to provide a light distribution control technique capable of reducing a sense of incongruity to a driver or the like when switching the light irradiation state.

  The lighting control device for a vehicle headlamp according to one aspect of the present invention includes (a) lighting control for a vehicle headlamp capable of individually irradiating each of a plurality of segments arranged in at least one direction. (B) a vehicle detection unit that detects the position of a preceding vehicle, (c) a light irradiation range setting unit that sets a light irradiation range and a non-irradiation range according to the position of the preceding vehicle, d) Based on the light irradiation range and the non-irradiation range, in each of the plurality of segments, among the segments that were in the extinguished state corresponding to the non-irradiation range, with a change in the position of the non-irradiation range A switching segment determination unit that determines whether or not there are a plurality of switching target segments that can be switched to a lighting state corresponding to the light irradiation range; and (e) a movement direction determination unit that determines a movement direction of the non-irradiation range; (F) Said cut When there are a plurality of target segments, a lighting timing setting unit that sets the order of switching each switching target segment to a lighting state corresponding to the moving direction of the non-irradiation range, and (g) the light irradiation range and A lighting control unit that supplies a light distribution control signal for individually lighting or extinguishing the plurality of segments to the vehicle headlamp based on the non-irradiation range and the order. This is a lighting control device for a headlamp.

  According to the above configuration, it is possible to reduce a sense of discomfort to the driver or the like when switching the light irradiation state.

  In the above lighting control device, the lighting timing setting unit sets the order so that the switching target segment is switched to the lighting state with a time difference in order from the farthest from the non-irradiation range after the position change. Is preferred.

  A vehicle headlamp system according to an aspect of the present invention is a vehicle headlamp system including the lighting control device described above and a vehicle headlamp controlled by the lighting control device.

  According to the above configuration, it is possible to reduce a sense of discomfort to the driver or the like when switching the light irradiation state.

FIG. 1 is a block diagram illustrating a configuration of a vehicle headlamp system according to an embodiment. FIG. 2 is a conceptual diagram illustrating the contents of information processing by the moving direction determination unit, the switching segment determination unit, and the lighting timing setting unit. FIG. 3 is a flowchart showing an operation procedure of the vehicle headlamp system. FIG. 4A, FIG. 4B, and FIG. 4C are conceptual diagrams showing an example of the operation contents of the vehicle headlamp system of the present embodiment. FIG. 5A and FIG. 5B are conceptual diagrams showing operation contents of the vehicle headlamp system of the comparative example.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 is a block diagram illustrating a configuration of a vehicle headlamp system according to an embodiment. The vehicle headlamp system of the present embodiment is capable of individually irradiating light to each of a plurality of segments (divided regions) arranged along the vehicle width direction, and includes a camera 10 and a vehicle detection unit 11. The controller 12 includes a pair of lamp units (vehicle headlamps) 20R and 20L. In the present embodiment, the camera 10, the vehicle detection unit 11, and the control unit 12 correspond to a “lighting control device”.

  The camera 10 is installed at a predetermined position of the host vehicle (for example, on the dashboard, the upper part of the windshield, etc.), and images the front space of the host vehicle. The vehicle detection unit 11 detects the position of a forward vehicle (an oncoming vehicle or a preceding vehicle) that exists in front of the host vehicle based on an image of the front space of the vehicle that is captured by the camera 10. In addition, the camera 10 and the vehicle detection part 11 may be comprised integrally. On the other hand, the function of the vehicle detection unit 11 may be realized in the control unit 12.

  The control unit 12 performs control for selectively irradiating light corresponding to the position of the preceding vehicle detected by the vehicle detection unit 11, and includes a light irradiation range setting unit 13, a switching segment determination unit 14, A moving direction determination unit 15, a lighting timing setting unit 16, and a lighting control unit 17 are included. The control unit 12 is configured by executing a predetermined operation program in a computer system including, for example, a CPU, a ROM, a RAM, and the like.

  The light irradiation range setting unit 13 sets a certain range including the position of the preceding vehicle detected by the vehicle detection unit 11 as a non-irradiation range of light among all the ranges that can be irradiated by the lamp units 20R and 20L. The range is set as the light irradiation range.

  Based on the light irradiation range and the non-irradiation range set by the light irradiation range setting unit 13, the switching segment determination unit 14 selects the non-irradiated segment associated with the non-irradiation range in each segment. It is determined whether or not there are a plurality of segments that are associated with the light irradiation range and switched to the lighting state by the movement of the irradiation range.

  The movement direction determination unit 15 determines the movement direction of the non-irradiation range set by the light irradiation range setting unit 13.

  The lighting timing setting unit 16 determines the lighting timing (lighting timing) by the moving direction determination unit 15 when there are a plurality of segments determined by the switching segment determination unit 14 to be switched from the unlit state to the lighting state. It is set according to the moving direction of the non-irradiation range.

  The lighting control unit 17 is for turning on or off each segment individually based on the light irradiation range and the non-irradiation range set by the light irradiation range setting unit 13 and the lighting timing set by the lighting timing setting unit 16. A light distribution control signal for forming a light distribution pattern is output to each of the lamp units 20R and 20L.

  Each of the lamp units 20R and 20L is disposed on the left and right in front of the host vehicle, and the light distribution according to the position of the vehicle ahead based on the light distribution control signal supplied from the lighting control unit 17 of the control unit 12. The pattern irradiation light is generated. As such lamp units 20R and 20L, various lamp units can be used as long as selective light irradiation can be performed. Specifically, for example, it is possible to use a lamp unit that includes a plurality of light emitting elements (LEDs) and can individually turn on and off the light emitting elements and irradiate the vehicle forward.

  As each of the lamp units 20R and 20L, for example, a lamp unit that can turn on and off a semiconductor laser at high speed, scan the emitted light, and irradiate the vehicle forward can be used. Alternatively, as each of the lamp units 20R and 20L, a lamp unit that forms a desired light distribution pattern by partially blocking the light emitted from the light source with a light shielding plate and can irradiate it in front of the host vehicle may be used. it can.

  FIG. 2 is a conceptual diagram illustrating the contents of information processing by the moving direction determination unit, the switching segment determination unit, and the lighting timing setting unit. Here, as an example, the number of segments that can be selectively irradiated with light by the lamp units 20R and 20L is 10, and the segments S1 to S10 are arranged in a line along the vehicle width direction (horizontal direction). Shall.

  Assume that the non-irradiation range set by the light irradiation range setting unit 13 at a certain time t1 has a range from the left end side of the segment S2 to the right end side of the segment S4 as shown in the figure. In addition, it is assumed that the regions on both sides of the non-irradiation range are set to the light irradiation range, respectively. In this case, the lighting control unit 17 controls the segments S2, S3, and S4 that overlap the non-irradiation range to be turned off, and the segments S1, S5 to S10 are controlled to be turned on. In this case, if the preceding vehicle has moved to the right between time t1 and the next time t2, the non-irradiation range set according to the position of the preceding vehicle also moves to the right as shown in the figure. It will be. Therefore, the moving direction of the non-irradiation range can be determined by comparing the positions of the non-irradiation ranges at a certain time t1 and the next time t2.

  In addition, among the segments S2 to S4 that are off in association with the non-irradiation range at time t1, the non-irradiation range is moved (position change) and switched to the lighting state in association with the light irradiation range at time t2. In the present example, the segments S2 to S4 correspond to the segments to be generated. For this reason, it can be determined that there are a plurality of segments that can be switched from the unlit state to the lit state. Note that two segments S2 and S3 may be switched, and one segment S2 may be switched.

  For example, the position of each segment, the non-irradiation range, and the like is expressed as an angle with respect to the predetermined position of the host vehicle, and the left boundary angle of the non-irradiation range at time t1 is ML1, and the non-irradiation range at time t2 is The left boundary angle is ML2, the right boundary angle of the segment S2 is S2R, the right boundary angle of the segment S3 is S3R, and the right boundary angle of the segment S4 is S4R. In this case, since ML1 <S2R <S3R <S4R at time t1, it can be seen that segments S2 to S4 correspond to the non-irradiation range at time t1. Further, since S4R <ML2 at time t2, it can be seen that segments S2 to S4 do not correspond to the non-irradiation range at time t2. From these, it can be determined that the segments S2 to S4 are switched to the lighting state at time t2.

  In this case, the lighting timing (lighting time) in each segment to be switched to the lighting state is set as follows. The segments S2 to S4 that are switched from the unlit state to the lit state are identified. Further, the moving direction of the non-irradiation range (right direction in the example of FIG. 2) is determined. At this time, the order in which the segments S2 to S4 are turned on is set corresponding to the moving direction of the non-irradiation range. Specifically, the segment S2 is first controlled to be lit, then the segment S3 is controlled to be lit, and then the segment S4 is controlled to be lit. Thereby, it switches to a lighting state continuously in order from segment S2 to segment S4.

An example of a lighting timing setting method will be described below. As described above, the left boundary angle of the non-irradiation range at time t1 is ML1, the left boundary angle of the non-irradiation range at time t2 is ML2, the right boundary angle of segment S2 is S2R, the right boundary angle of segment S3 is S3R, segment Let S4R be the right boundary angle of S4. Also, the number of segments that switch to the lighting state at time t2 is SN, and the number that counts the segment that switches to the lighting state from the outside (side closer to the non-irradiation range at time t1) (number counting in order from “1”) is ON. The time difference between the segment with the fastest lighting timing and the segment with the latest lighting timing is LT (for example, 1200 milliseconds), and the time coefficient is T (for example, 10). At this time, the standby time WT until the lighting starts for each segment can be set based on the following calculation formula.
WT = (LT × ON × (ON−1)) / (SN × (SN−1) × T) [ms]

  In the example shown in FIG. 2, for example, assuming that the time difference LT is 1200 milliseconds and the time coefficient is T = 10, the waiting time WT of the segment S2 (number ON = 1) is 0, and the segment S3 (number ON = The standby time WT of 2) is 40 [ms], and the standby time WT of the segment S4 (number ON = 1) is 120 [ms]. Therefore, the segment S2 is immediately controlled to be lit, the segment S3 is controlled to be lit 40 milliseconds later, and the segment S4 is controlled to be lit 120 milliseconds after the segment S2 is lit.

  FIG. 3 is a flowchart showing an operation procedure of the vehicle headlamp system. Hereinafter, the operation of the vehicle headlamp system will be described in detail with reference to this flowchart.

  When a vehicle ahead is detected by the vehicle detection unit 11 based on the image obtained by the camera 10 (step S11), the light irradiation range setting unit 13 determines the light irradiation range and the non-irradiation range based on the position of the front vehicle. Is set (step S12).

  Based on the light irradiation range and the non-irradiation range set by the light irradiation range setting unit 13, the switching segment determination unit 14 determines whether there are a plurality of segments that are switched to the lighting state (step S13).

  When there are a plurality of segments that can be switched to the lighting state (step S13; YES), the moving direction determination unit 15 determines whether or not the type of the preceding vehicle is “preceding vehicle” based on the detection result of the vehicle detection unit 11. Is determined (step S14).

  When the preceding vehicle is a preceding vehicle (step S14; YES), the movement direction determination unit 15 determines whether or not the movement direction of the non-irradiation range set by the light irradiation range setting unit 13 is the left direction. (Step S15). The moving direction of the non-irradiation range reflects the moving direction of the preceding vehicle.

  When the moving direction of the non-irradiation range is the left direction (step S15; YES), the lighting timing setting unit 16 sets the lighting order of each segment from “right to left” (step S16). On the other hand, when the moving direction of the non-irradiation range is not the left direction, that is, the right direction (step S15; NO), the lighting timing setting unit 16 sets the lighting order of each segment from “left to right”. (Step S17).

  Next, the lighting timing setting unit 16 sets the lighting timing of each segment according to the set lighting order (step S18). The lighting control unit 17 is for turning on or off each segment individually based on the light irradiation range and the non-irradiation range set by the light irradiation range setting unit 13 and the lighting timing set by the lighting timing setting unit 16. A light distribution control signal for forming a light distribution pattern is output to each lamp unit 20R, 20L (step S19).

  On the other hand, when it is determined in step S14 that the type of the preceding vehicle is not “preceding vehicle”, that is, “oncoming vehicle” (step S14; NO), the moving direction determination unit 15 determines that the host vehicle is It is determined whether the vehicle is traveling in the left lane (step S20). For this determination, for example, the vehicle detection unit 11 can detect the travel lane of the host vehicle and use the detection result.

  When the host vehicle is traveling in the left lane (step S20; YES), the lighting timing setting unit 16 sets the lighting order of each segment from “right to left” (step S21). On the other hand, when the host vehicle is not traveling in the left lane, that is, is traveling in the right lane (step S21; NO), the lighting timing setting unit 16 changes the lighting order of each segment from “left to right”. Set (step S22).

  Next, the lighting timing setting unit 16 sets the lighting timing of each segment according to the set lighting order (step S18). The lighting control unit 17 is for turning on or off each segment individually based on the light irradiation range and the non-irradiation range set by the light irradiation range setting unit 13 and the lighting timing set by the lighting timing setting unit 16. A light distribution control signal for forming a light distribution pattern is output to each lamp unit 20R, 20L (step S19).

  If the number of segments to be switched to the lighting state is not plural in the above-described step S13 (the number of segments is 1 or 0) (step S13; NO), the lighting timing is not controlled, and the light A normal light distribution control signal based on the light irradiation range and the non-irradiation range set by the irradiation range setting unit 13 is executed.

  FIG. 4A, FIG. 4B, and FIG. 4C are conceptual diagrams showing an example of the operation contents of the vehicle headlamp system of the present embodiment. As shown in FIG. 4A, it is assumed that the forward vehicle is moving in the left direction in the figure, and the movement direction of the non-irradiation range specified along with the vehicle is the left direction. At this time, at time t1, the segments S6 to S10 corresponding to the non-irradiation range are controlled to be turned off, and the segments S1 to S5 corresponding to the light irradiation range are controlled to be turned on.

  At time t2 after time t1, as shown in FIG. 4B, the non-irradiation range is moved due to the movement of the preceding vehicle, and accordingly, the segments S4 to S7 are controlled to be turned off, and the segment S1 -S3 and S8-S10 are controlled to a lighting state. At this time, corresponding to the moving direction of the non-irradiation range (from right to left in the figure), the segments S8 to S10 are controlled to be lit with a time difference in the order of the segment S10, the segment S9, and the segment S8. As a result, the light is gradually emitted from the segment S10 to the segment S8. This difference in lighting timing is represented by a difference in hatching density in FIG. After the segments S8 to S10 are sequentially controlled to be turned on, as shown in FIG. 4C, all the segments S8 to S10 are turned on with a prescribed light intensity.

  FIG. 5A and FIG. 5B are conceptual diagrams showing operation contents of the vehicle headlamp system of the comparative example. The comparative example referred to here is a vehicle headlamp system that simply switches each segment to a lighting state or a non-lighting state corresponding to a light irradiation range and a non-irradiation range. As shown in FIG. 5A, the preceding vehicle, which is the preceding vehicle, is moving in the left direction in the figure, and the segments S6 to S10 corresponding to the non-irradiation range are controlled to be turned off at a certain time t1, and the light irradiation range The segments S1 to S5 corresponding to are controlled to be lit. At the subsequent time t2, as shown in FIG. 5 (B), the non-irradiation range is moved due to the movement of the front vehicle, and accordingly, the segments S4 to S7 are controlled to be turned off, and the segments S1 to S3, S8-S10 are controlled to a lighting state. At this time, in the segments S8 to S10 switched from the unlit state to the lit state, a sudden change in light intensity may cause the driver to feel uncomfortable.

  As described above, according to the present embodiment, in the vehicle headlamp system capable of individually irradiating light to each of the plurality of segments, it is possible to reduce a sense of discomfort to the driver or the like when switching the light irradiation state. Is possible.

  In addition, this invention is not limited to the content of embodiment mentioned above, In the range of the summary of this invention, it can change and implement variously. For example, in the above-described embodiment, a plurality of segments arranged in the vehicle width direction are described as an example of a plurality of segments that can be individually irradiated with light. However, a plurality of directions, for example, a vehicle width direction and a vehicle height direction are described. The present invention can be similarly applied when a plurality of segments are arranged in two directions.

DESCRIPTION OF SYMBOLS 10: Camera 11: Vehicle detection part 12: Control part 13: Light irradiation range setting part 14: Switching segment determination part 15: Movement direction determination part 16: Lighting timing setting part 17: Lighting control part 20R, 20L: Lamp unit (vehicle Headlamps)

Claims (3)

A lighting control device for a vehicle headlamp capable of individually irradiating light to each of a plurality of segments arranged in at least one direction,
A vehicle detection unit for detecting the position of the preceding vehicle;
A light irradiation range setting unit that sets a light irradiation range and a non-irradiation range according to the position of the preceding vehicle;
Based on the light irradiation range and the non-irradiation range, in each of the plurality of segments, out of the segments that are in the extinguishment state corresponding to the non-irradiation range, the light according to the change in the position of the non-irradiation range A switching segment determination unit that determines whether or not there are a plurality of switching target segments that can be switched to a lighting state corresponding to the irradiation range;
A moving direction determination unit that determines a moving direction of the non-irradiation range;
When there are a plurality of the switching target segments, a lighting timing setting unit that sets the order of switching each switching target segment to the lighting state corresponding to the moving direction of the non-irradiation range;
Based on the light irradiation range, the non-irradiation range, and the order, a light distribution control signal for forming a light distribution pattern for individually turning on or off the plurality of segments is used for the vehicle headlamp. A lighting control unit that outputs to
A lighting control device for a vehicle headlamp. The lighting timing setting unit sets the order so that the switching target segment is switched to the lighting state with a time difference in order from the farther from the non-irradiation range after the position change,
The lighting control device for a vehicle headlamp according to claim 1.   A vehicle headlamp system comprising the lighting control device according to claim 1 and a vehicle headlamp controlled by the lighting control device.

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