WO2013137324A1

WO2013137324A1 - Vehicle-mounted illumination device

Info

Publication number: WO2013137324A1
Application number: PCT/JP2013/057022
Authority: WO
Inventors: 龍水野
Original assignee: 株式会社デンソー
Priority date: 2012-03-14
Filing date: 2013-03-13
Publication date: 2013-09-19
Also published as: JP2013189105A

Abstract

In the present invention, in the state of a headlight illuminating the direction of progression, the strength of the light of the headlight is dimmed (or extinguished) to no greater than a predetermined strength across a predetermined dimming time. In such a state, an image (image when dimmed) is acquired of the direction of progression of the vehicle. In the image when dimmed, reflective objects such as at the roadside appear dark, and the headlights of oncoming traffic appears bright. Thus, it is possible to easily and precisely determine the presence/absence of oncoming traffic. As a result, when it is determined that there is oncoming traffic in the image when dimmed, the illumination range of the headlights are set at a second illumination range that is narrower than a first illumination range.

Description

In-vehicle lighting system

The present invention relates to an in-vehicle illumination device that illuminates the traveling direction of a vehicle.

It is desirable to illuminate as wide a range as possible in order to ensure the driver's visibility when the vehicle is traveling at night. On the other hand, it is desirable not to directly illuminate the oncoming vehicle in order not to disturb the driving of the driver traveling on the oncoming lane. In view of these circumstances, an in-vehicle illumination device for not directly illuminating an oncoming vehicle has been proposed. In such an in-vehicle lighting device, an image of the traveling direction of the vehicle is acquired to determine whether there is an oncoming vehicle. When an oncoming vehicle exists in the image, illumination is performed while avoiding the range (the range in which the oncoming vehicle is present) or reducing the illuminance in the range. Judgment of the presence or absence of an oncoming vehicle is performed by detecting the headlamp of the oncoming vehicle that appears bright in the image (see Patent Document 1).

JP 2006-21631 A

However, the above-mentioned in-vehicle lighting device has the following problems. In other words, if the reflectors (reflectors, road signs, etc.) provided on the side of the road or in the median strip appear bright in the image, the above-mentioned in-vehicle lighting device misrecognizes the bright part as the headlight of the oncoming vehicle. There are things to do. In such a case, in the on-vehicle lighting device described above, lighting is performed while avoiding a brightly reflected range or lowering the illuminance, which may limit the driver's field of view.

Therefore, in view of the above-described problems, it is desirable to provide an in-vehicle lighting device that does not limit the driver's field of view because of misrecognition that an oncoming vehicle exists.

In order to solve the above-described problem, the in-vehicle illumination device according to the present disclosure reduces the intensity of light from a headlamp to a predetermined intensity or less over a predetermined time, thereby reducing the intensity of light from the headlamp. In an illuminated state (hereinafter referred to as a dimmed state), an image in the traveling direction of a vehicle (hereinafter simply referred to as a vehicle) equipped with the in-vehicle illumination device of the present disclosure is acquired. And the presence or absence of an oncoming vehicle is judged based on the image (image at the time of light reduction) acquired in the light reduction state. When it is determined that there is an oncoming vehicle, the headlamp illumination range is changed.

In such an in-vehicle illumination device of the present disclosure, the illumination range in the traveling direction of the vehicle is divided into a first illumination range in which light reaches a wide left and right range in the traveling direction, and a second illumination that is narrower than the first illumination range. The range can be changed. The illumination range is set as follows. First, with the headlamp illuminating the direction of travel, the intensity of the headlamp light is dimmed below a predetermined intensity over a predetermined time. The “dimming” is a concept including “light-off”. And the image of the advancing direction of a vehicle is acquired in the state which reduced the intensity | strength of light. In an image acquired while the headlamp is dimmed (image at the time of dimming), reflective objects such as the roadside appear dark, and the headlamp of the oncoming vehicle appears bright. Therefore, if it is determined based on the image at the time of dimming, the presence or absence of the oncoming vehicle can be easily and accurately determined. And when it is judged that an oncoming vehicle exists in the image at the time of light reduction, the illumination range of a headlamp is set to a 2nd illumination range.

In this way, there is no possibility that a reflector provided on the side of the road is mistakenly detected as a headlight of an oncoming vehicle. For this reason, although the oncoming vehicle does not actually exist, the illumination range of the headlamp is not set to the second illumination range that is narrower than the first illumination range. Therefore, the driver's field of view is not limited.

Further, in the above-described in-vehicle illumination device of the present disclosure, an image in the traveling direction of the vehicle may be acquired even in a normal state where the intensity of the headlamp light is not dimmed. Then, it may be determined whether or not the headlamp is dimmed based on an image acquired in a normal state (normal image).

In this way, the process of setting the headlamp to a dimmed state or acquiring an image at the time of dimming may be performed only when necessary. Therefore, the illumination control process can be simplified.

Or in the vehicle-mounted illumination device of the present disclosure described above, the dimming state may be set at a predetermined cycle without determining whether or not the headlamp is dimmed.

In this way, it is not necessary to determine whether or not the headlamp is dimmed. Therefore, the illumination control process can be simplified.

In addition, in the in-vehicle illumination device of the present disclosure that periodically dims the headlamp, information on the running state of the vehicle (running state information) is acquired and the headlamp is turned on at a cycle according to the running state information. It is good also as a dimming state.

In this way, it is possible to transmit the traveling state information of the vehicle to another vehicle equipped with the in-vehicle lighting device of the present disclosure using the cycle of dimming the headlamp. Therefore, the traveling state information of the other vehicle can be acquired from the cycle in which the headlamps of the other vehicle are dimmed. In this way, it is possible to ensure traveling safety using the acquired traveling state information.

It is explanatory drawing which shows the structure of the vehicle-mounted illuminating device by one Example of this invention; It is an explanatory view showing the illumination range in the view priority mode and the illumination range in the view restriction mode of the in-vehicle illumination device; It is a flowchart of the illumination control process which the said vehicle-mounted illumination device performs in order to switch a visual field priority mode and a visual field restriction | limiting mode; It is a time chart which shows a mode that the said vehicle-mounted illuminating device switches a visual field priority mode and a visual field restriction | limiting mode; It is explanatory drawing which illustrated the front image in the lighting state of the said vehicle-mounted illumination device, and the front image in a light extinction state; It is a time chart which shows a mode that the vehicle-mounted illuminating device of a 1st modification switches a visual field priority mode and a visual field restriction | limiting mode; It is a flowchart of the illumination control process which the vehicle-mounted illuminating device of a 2nd modification performs.

Hereinafter, an embodiment of the present invention will be described in order to clarify the contents of the present invention described above with reference to the accompanying drawings.

As shown in FIG. 1, the in-vehicle illumination device 100 of this embodiment includes a headlight 110, a headlight control unit 112, a front camera 120, a control device 130, and the like, and is mounted on the vehicle 1. The headlamp 110 illuminates the traveling direction of the vehicle 1. The headlamp control unit 112 controls the operation of the headlamp 110. The front camera 120 acquires an image in the traveling direction. The control device 130 controls the headlamp control unit 112 and the front camera 120.

The headlamp 110 is configured by incorporating a plurality of light emitting diodes (LEDs), and each LED can be quickly switched between a lighting state and a light-off state. The headlamp control unit 112 controls the switching of each LED to a lighted state or a lighted off state, and controls to change the illumination range of the headlight 110 by moving the optical axis of each LED. The headlamp control unit 112 may change the illumination range by moving the optical axis of the entire headlamp 110.

The front camera 120 is equipped with an image sensor and can output two-dimensional image data. In the image sensor, elements such as a charge-coupled device (CCD) and a complementary metal oxide semiconductor (CMOS) are arranged in a matrix. The front camera 120 of this embodiment corresponds to “image acquisition means”.

The control device 130 is a so-called microcomputer in which a CPU, a ROM, a RAM, and the like are connected by a bus so that data can be read and written. Various programs and data necessary for executing the programs are stored in advance in the ROM. Various processes are performed by the CPU reading programs and data from the ROM and executing the programs using the RAM.

As shown in FIG. 1, the control device 130 of this embodiment includes an image processing module 132 and a control module 134. The “module” is an abstract concept when the control device 130 is divided for convenience from the viewpoint of the functions realized by the control device 130. Specifically, the module entity may include a part of a program, a collection of a plurality of programs, or hardware mounted on the control device 130.

When the image processing module 132 receives the image data of the front image (image in the traveling direction of the vehicle 1) acquired by the front camera 120, the image processing module 132 performs predetermined image processing. As a result, the image processing module 132 detects the headlamp of the oncoming vehicle and outputs the result to the control module 134.

When the headlamp 110 is turned on by the driver of the vehicle 1, the control module 134 outputs a trigger signal instructing the front camera 120 to acquire a front image at a constant cycle (for example, 20 msec). Further, the headlamp 110 can change the illumination range. A signal (mode signal) for setting the illumination range is output from the control module 134 to the headlamp control unit 112.

Furthermore, as will be described later, the in-vehicle illumination device 100 according to the present embodiment can turn off the headlamp 110 for a predetermined turn-off time even when the headlamp 110 is turned on by the driver. Yes. When the headlamp 110 is turned off for a predetermined time when the headlamp 110 is in a lighting state, the control module 134 sends a turn-off signal that turns off the headlamp 110 for the turn-off time to the headlamp control unit 112. Output. The turn-off time is set to a time (for example, 2 msec) that is approximately the same as or shorter than the period in which the front camera 120 acquires the front image. Further, in the following description, it is assumed that the headlamp 110 is “turned off” for the turn-off time while being turned on by the driver. However, “light-off” does not necessarily mean “complete light-off”, but also includes “light-reduction” meaning to reduce the light intensity. The “dimming” is sufficient if it can be clearly recognized by the image processing module 132 that the light intensity of the headlamp 110 is low. For example, the light intensity of the headlamp 110 may be reduced to less than half. Thus, in the present embodiment, the headlamp 110 is turned off or dimmed when the control module 134 outputs a turn-off signal. Therefore, the control module 134 corresponds to “dimming means”. In addition, the turn-off time in this embodiment corresponds to the “dimming time”.

2A and 2B illustrate the first illumination range and the second illumination range of the headlamp 110, respectively. In the figure, a case where the vehicle 1 is traveling on a road with one lane on one side (two lanes on both sides) is shown, and a thick broken line in the figure represents a center line. In addition, the hatched area in the figure represents a range where the light from the headlamp 110 does not reach. In the first illumination range shown in FIG. 2A, the light from the headlamp 110 reaches a wide left and right range in the traveling direction of the vehicle 1. For this reason, the driver | operator of the vehicle 1 can ensure sufficient visual field. However, since the light reaches a wide range of the oncoming lane, the driver of the oncoming vehicle may feel dazzled. On the other hand, in the second illumination range shown in FIG. 2B, the range in which light reaches the oncoming lane is narrow. For this reason, although there is no fear that the driver of the oncoming vehicle feels dazzling, the field of view of the driver of the vehicle 1 is limited compared to the first illumination range.

In the in-vehicle illumination device 100 of the present embodiment, two modes of “view priority mode” and “view restriction mode” are set as the illumination modes of the headlamp 110. The first illumination range is used in the view priority mode, and the second illumination range is used in the view restriction mode. As described with reference to FIG. 1, the control module 134 outputs to the headlamp control unit 112 which mode is set by outputting a mode signal. The headlamp controller 112 controls the headlamp 110 according to the mode signal, thereby realizing an illumination range corresponding to the designated illumination mode. Thus, in the present embodiment, the illumination range of the headlamp 110 is set by the control module 134 outputting the mode signal. Therefore, the control module 134 corresponds to “illumination range setting means”.

Also, the illumination mode designated by the control module 134 for the headlamp control unit 112 is determined by whether or not the image processing module 132 detects an oncoming vehicle from the front image. That is, when no oncoming vehicle is detected in the front image, the view priority mode is determined in order to sufficiently secure the driver's view. On the other hand, when an oncoming vehicle is detected, the visibility restriction mode is determined so that the driver of the oncoming vehicle does not feel dazzling. Thus, in this embodiment, the image processing module 132 detects the presence or absence of an oncoming vehicle in the front image. Therefore, the image processing module 132 corresponds to “oncoming vehicle determination means”.

[Lighting control processing]
Reflectors such as reflectors and road signs are usually installed on the side of the road or on the center line. For this reason, when the front camera 120 acquires a front image, the light of the headlamp 110 may be reflected and these reflections may appear brightly in the front image. Then, the image processing module 132 misrecognizes the reflected object as the headlight of the oncoming vehicle, and the illumination mode of the headlight 110 is set to the view restriction mode even though the oncoming vehicle does not actually exist. It can happen to switch. Since the illumination range is set to the second illumination range in the view restriction mode, the driver's view is restricted as compared to the view priority mode. Therefore, in the in-vehicle illumination device 100 of the present embodiment, the following processing is performed, and the reflected object appears brightly in the front image, so the image processing module 132 may misrecognize that an oncoming vehicle exists. Make sure there is no.

FIG. 3 shows a flowchart of the illumination control process executed by the in-vehicle illumination device 100 of this embodiment. This lighting control process is a process that is automatically executed by the control device 130 (image processing module 132, control module 134, etc.) of the in-vehicle lighting device 100 when the driver of the vehicle 1 lights the headlamp 110. When the illumination control process is started, the control device 130 first sets the headlamp 110 to the view priority mode (step S100). When setting the visibility priority mode, the control module 134 outputs a mode signal for designating the visibility priority mode to the headlamp control unit 112.

Subsequently, the control device 130 determines whether or not the interval time has elapsed (step S102). Here, the interval time is a time (for example, 20 msec) corresponding to a period in which the front camera 120 acquires a front image. In this embodiment, when the illumination control process is started and the headlamp 110 is first set to the visibility priority mode in step S100, a timer (not shown) built in the control device 130 is set, The interval time is started.

As a result, when it is determined that the interval time has not elapsed (step S102: NO), the control device 130 is in a standby state while repeating the same determination. On the other hand, when determining that the interval time has elapsed (step S102: YES), the control device 130 causes the front camera 120 to output a trigger signal from the control module 134 to acquire a front image (step S104). That is, when the front camera 120 receives the trigger signal, the image data remaining in the built-in image sensor is reset. Thereafter, the front camera 120 opens the shutter for a predetermined exposure time and generates new image data on the image sensor. The image data obtained in this way is data indicating a two-dimensional luminance distribution on the image sensor. The front camera 120 outputs the image data thus obtained to the image processing module 132.

When the image data of the front image is received from the front camera 120, the control device 130 (specifically, the image processing module 132) performs the following image processing. Thereby, the control apparatus 130 judges whether the bright spot which becomes a candidate of an oncoming vehicle exists in a front image (step S106). In this image processing, first, a luminance region (bright spot) is extracted by comparing the luminance indicated in the image data with a predetermined threshold value. If the headlight of the oncoming vehicle is reflected in the front image, then two bright spots of similar size should be captured side by side. However, the interval and direction of the two bright spots vary depending on the distance from the oncoming vehicle, the slope of the road surface, and the like. Therefore, for the interval and direction of the bright spots, an allowable range with a certain margin is set in the image processing module 132, and a bright spot pair that satisfies this allowable range is searched. If no such bright spot pair is found, the image processing module 132 determines that there is no bright spot that is a candidate for the oncoming vehicle (step S106: NO), and the control returns to step S100. In step S100, the image processing module 132 sets the headlamp 110 to the visibility priority mode, and then starts measuring the interval time (step S102). On the other hand, when a pair of bright spots that satisfy the allowable range is found, the image processing module 132 determines that there is a bright spot that is a candidate for an oncoming vehicle (step S106: YES).

Thus, when a bright spot that is a candidate for an oncoming vehicle is found, the control device 130 (specifically, the control module 134) outputs a turn-off signal (step S108). Here, the turn-off signal is a signal that the control module 134 instructs the headlamp control unit 112 to turn off the headlamp 110 that is turned on for the aforementioned turn-off time. The headlamp 110 may be simply dimmed rather than completely turned off. Further, in this embodiment, when the image processing module 132 detects a bright spot that is a candidate for an oncoming vehicle from the front image when the headlamp 110 is lit, the control module 134 outputs a turn-off signal. Therefore, in the present embodiment, the image processing module 132 corresponds to “light reduction determination means”. Further, the front image when the headlamp 110 is lit corresponds to the “normal image”.

Subsequently, the control module 134 outputs a trigger signal to the front camera 120 while the headlamp 110 is turned off (or dimmed), thereby acquiring a front image that is turned off (or dimmed). (Step S110). In addition, since an afterimage phenomenon exists in human vision, even if the headlamp 110 is turned off (or dimmed) for a short time, the driver does not notice that. In this embodiment, the turn-off time of the headlamp 110 is set to a time that is approximately the same as or shorter than the period (for example, 20 msec) at which the front camera 120 acquires the front image. For this reason, the driver does not notice that the headlamp 110 is turned off (or dimmed). The front image acquired by the front camera 120 while the headlamp 110 is turned off (or dimmed) corresponds to the “image during dimming”.

Subsequently, the control device 130 determines whether or not a bright spot extracted as a candidate for an oncoming vehicle from the previously acquired lit front image is present in the unlit front image (step S112). The determination is made as follows. The bright spot previously extracted from the front image may be the headlight of the oncoming vehicle. In this case, the bright spot should also appear in the front image being turned off. Conversely, the bright spot previously extracted from the front image as a candidate for an oncoming vehicle may be reflected in the front image by reflection of the light from the headlight 110 of the vehicle 1 by a reflector such as a roadside. is there. In this case, the bright spot should have disappeared in the front image being turned off. Therefore, if a candidate bright spot remains in the front image being turned off (step S112: YES), it can be determined that an oncoming vehicle exists. Therefore, the control device 130 sets the headlamp 110 to the view restriction mode so as not to bother the driver of the oncoming vehicle (step S114). When setting the view restriction mode, the control module 134 outputs a mode signal designating the view restriction mode to the headlamp control unit 112.

On the other hand, when the bright spot extracted as the oncoming vehicle candidate is not in the front image being turned off (step S112: NO), the bright spot is the light from the headlamp 110 of the vehicle 1. Is reflected by a reflector on the side of the road, etc., and can be determined not to be a headlight of an oncoming vehicle. Therefore, the control device 130 determines whether or not the current illumination mode is the view restriction mode (step S116). When determining that the current illumination mode is the view restriction mode (step S116: YES), the control device 130 sets the headlamp 110 to the view priority mode (step S118). Thereafter, the control returns to step S102. In step S102, the control device 130 sets a built-in timer with confidence, and starts counting the interval time again. On the other hand, when the control device 130 determines that the current illumination mode is the view priority mode (step S116: NO), the control immediately returns to step S102. In step 102, the control device 130 sets the timer again and starts measuring the interval time.

FIG. 4 illustrates a state in which the illumination mode of the headlamp 110 is switched by the illumination control process described above. The illumination mode of the headlamp 110 is initially set to the visibility priority mode (see step S100 in FIG. 3). Further, the front camera 120 acquires a front image every time a predetermined interval time elapses. If there is no bright spot that is a candidate for an oncoming vehicle in the acquired forward image, the headlamp 110 is kept lit in that illumination mode. Then, when the interval time elapses, the front camera 120 acquires the front image again.

While repeating such operations, if a bright spot that is a candidate for an oncoming vehicle is found in the front image (corresponding to step S106: YES in FIG. 3), the control module 134 sends the headlight control unit 112 to A turn-off signal is output. As a result, the headlamp 110 is turned off for a predetermined turn-off time. In the example shown in FIG. 4, the extinguishing signal is ON only during the extinguishing time, and the extinguishing state of the headlamp 110 is ended when the extinguishing signal is turned off. However, the turn-off signal may be turned on only for a short time, and the headlight 110 may be kept off during the subsequent turn-off time.

Then, while the headlamp 110 is in the off state, a front image is acquired by the front camera 120 (corresponding to step S110 in FIG. 3). If a bright spot that is a candidate for an oncoming vehicle does not remain in the acquired forward image, the bright spot can be determined not to be due to the headlamp of the oncoming vehicle. Therefore, the view priority mode is maintained as it is. Thereafter, when the interval time elapses, the front camera 120 acquires the front image again.

In the example shown in FIG. 4, since a bright spot that is a candidate for an oncoming vehicle is found in the forward image acquired at the timing of time a, the headlamp 110 is turned off and the forward image that is turned off is acquired. is doing. However, there is no candidate bright spot in the extinguished front image, so that the view priority mode is maintained as it is. And if interval time passes, a front image will be acquired again.

While repeating such operations, a bright spot that is a candidate for an oncoming vehicle is found from the front image acquired while the headlamp 110 is lit, and then acquired with the headlamp 110 turned off. In some cases, the candidate bright spot remains in the forward image. In this case, it can be determined that the bright spot is the headlight of the oncoming vehicle (corresponding to step S112: YES in FIG. 3). Therefore, the illumination mode of the headlamp 110 is set to the view restriction mode.

In the example illustrated in FIG. 4, a bright spot that is a candidate for an oncoming vehicle is found in the forward image acquired at the timing of time b, and the bright spot is also present in the forward image acquired while the headlamp 110 is turned off. Therefore, a state in which the illumination mode is changed to the view restriction mode is shown. Even in the view restriction mode, the front image is acquired every time the interval time elapses. In other words, in the example illustrated in FIG. 4, a front image is acquired even at time c when the interval time has elapsed from time b, and it is determined whether there is a bright spot that is a candidate for an oncoming vehicle. In the illustrated example, since a candidate bright spot is found at time c, the headlamp 110 is turned off and the front image is acquired again. As a result, since a candidate bright spot is also present in the front image being turned off, it is shown that the view restriction mode is maintained as it is.

While such an operation is repeated, whether a bright spot that is a candidate for an oncoming vehicle is not found in the front image when the headlamp 110 is lit (corresponds to NO in step S106 in FIG. 3) or lit. A case where the candidate bright spot found in the front image in the middle is not found in the front image being turned off (corresponding to step S112 in FIG. 3: NO) occurs. In such a case, it can be determined that there is no oncoming vehicle. Therefore, the illumination mode of the headlamp 110 is set to the view priority mode.

In the example illustrated in FIG. 4, a bright spot that is a candidate for an oncoming vehicle is found in the on-front image acquired at the time d, but the bright spot is displayed on the front image when the headlamp 110 is off. Is not found, so that the lighting mode is returned to the view priority mode. Thereafter, the forward image is acquired every time the interval time elapses.

In this way, using not only the front image acquired while the headlamp 110 is turned on but also the front image acquired while the light is turned off, it is ensured that a reflector on the roadside or the center line is erroneously detected as an oncoming vehicle. Can be avoided. In the following, this point will be supplementarily described.

FIG. 5A illustrates a front image obtained while the headlamp 110 is turned on. FIG. 5B illustrates a front image obtained while the headlamp 110 is turned off. The thick broken line shown in FIG. 5 represents the center line, and the thick solid line represents the boundary between the road surface and the road shoulder. Reflectors such as reflectors and road signs are provided on the side of the road and on the center line to alert the driver. For this reason, when the headlamp 110 is turned on, as shown in FIG. 5A, the light reflected by these reflectors may appear as a bright spot in the front image. In addition, when there is an oncoming vehicle, the headlamp of the oncoming vehicle is also reflected in the front image as a bright spot. In the example shown in FIG. 5A, the bright spots a to j are bright spots corresponding to the reflectors, and the two bright spots k1 and k2 are bright spot pairs corresponding to the headlamps of the oncoming vehicle. It is.

However, when a plurality of bright spots are reflected as shown in FIG. 5A, two of the plurality of bright spots happen to be pairs of bright spots corresponding to the headlights of the oncoming vehicle. It can happen to be visible. Therefore, although the oncoming vehicle does not actually exist, the illumination mode of the headlamp 110 may be switched from the view priority mode to the view restriction mode, and the driver's view may be restricted.

On the other hand, as shown in FIG. 5 (b), in the front image obtained by turning off the headlamp 110, the bright spots (a to j) corresponding to the reflecting object are not captured. Some of the bright spots are not mistakenly recognized as bright spots corresponding to the headlights of the oncoming vehicle. For this reason, although the oncoming vehicle does not actually exist, the illumination mode of the headlamp 110 does not switch from the view priority mode to the view restriction mode. Therefore, it is possible to avoid the driver's view being limited.

Of course, there may be a case where the on-vehicle illumination device 100 of the present embodiment is also mounted in the oncoming vehicle and the headlamp is turned off only for a short time. In this case, when the headlight 110 of the vehicle 1 is turned off and a front image is acquired, if the headlight of the oncoming vehicle happens to be turned off, the headlight of the oncoming vehicle is erroneously recognized as a reflector. End up. However, since the turn-off time is short, during the turn-off time of the headlight of the oncoming vehicle, the headlight 110 of the vehicle 1 happens to be turned off and the front camera 120 acquires the front image. It can hardly happen. Therefore, actually, even when the on-vehicle lighting device 100 of this embodiment is mounted on an oncoming vehicle, the headlamp of the oncoming vehicle is not erroneously recognized as a reflector.

Also, when extracting the bright spot in the front image, the brightness indicated in the image data is compared with a predetermined threshold value, and a region with a high brightness is extracted as the bright spot. For this reason, even if the headlamp 110 is not completely turned off, if the intensity of the light from the headlamp 110 is reduced to such an extent that the reflected object is not extracted as a bright spot by the image processing module 132, The description applies as well. Accordingly, similar effects can be obtained even in this way.

[Modification]
There are several modifications to the in-vehicle lighting device 100 of the present embodiment described above. Hereinafter, these modified examples will be described focusing on differences from the present embodiment. In the modification described below, the same reference numerals are given to the same configurations as those in the above-described embodiments, and detailed description thereof is omitted.

[First Modification]
In the embodiment described above, when a bright spot that is a candidate for an oncoming vehicle exists in the front image acquired while the headlamp 110 is turned on, a turn-off signal is output to obtain the front image that is turned off. did. However, the extinguishing signal may be periodically output to obtain the extinguishing front image regardless of whether or not there is a bright spot that is a candidate for an oncoming vehicle in the oncoming front image.

FIG. 6 shows a state where the in-vehicle lighting device 100 according to the first modified example switches between the view priority mode and the view restriction mode. As shown in the figure, also in the first modification, a front image is acquired by the front camera 120 every time a certain interval time (for example, 20 msec interval) elapses. However, in the first modified example, although a bright point that is a candidate for an oncoming vehicle may exist in the front image that is lit, a turn-off signal is always output thereafter, and the front image that is turned off is acquired. Reflected objects provided on the side of the road or the like do not appear in the front image being extinguished thus obtained (see FIG. 5B). For this reason, an oncoming vehicle can be detected correctly without erroneously recognizing the reflecting object as an oncoming vehicle. Therefore, as illustrated in FIG. 6, in the first modified example, when an oncoming vehicle is detected in the front image being turned off, the visibility restriction mode is set, and no oncoming vehicle is detected in the front image being turned off. In this case, the view priority mode may be set.

In the first modification described above, it is not necessary to determine whether or not there is a bright spot that is a candidate for an oncoming vehicle in the front image that is lit. For this reason, the illumination control process can be simplified. On the other hand, in the above-described embodiment, only when there is a bright spot that is a candidate for an oncoming vehicle in the front image that is lit, the turn-off signal is output and the headlamp 110 is turned off. What is necessary is just to acquire the inside front image. Therefore, in the above-described embodiment, it is possible to reduce the control load on the headlamp control unit 112 and the front camera 120.

[Second Modification]
In the first modification described above, when a front image with the headlamp 110 on is acquired, the headlamp 110 is always turned off to acquire a front image. Since the front camera 120 acquires a front image at a constant cycle (20 msec interval in the above-described embodiment and the first modification), the headlamp 110 is also turned off at the same cycle. However, the cycle for turning off the headlamp 110 is not necessarily a constant cycle. Therefore, it is possible to transmit some information of the vehicle 1 to the oncoming vehicle on which the in-vehicle lighting device 100 is mounted by changing the cycle in which the headlamp 110 is turned off.

FIG. 7 shows a flowchart of illumination control processing performed by the in-vehicle illumination device 100 according to the second modification. This lighting control process is automatically executed by the control device 130 of the in-vehicle lighting device 100 when the headlamp 110 is turned on by the driver of the vehicle 1, similarly to the lighting control processing of the above-described embodiment. Also in the illumination control process of the second modified example, the headlamp 110 is first set to the view priority mode (step S200).

Subsequently, in the lighting control process of the second modified example, information (traveling state information) related to the traveling state of the vehicle 1 is acquired (step S202). The traveling state information can include whether the vehicle 1 is accelerating or decelerating (that is, whether the accelerator pedal is depressed), the steering direction, the vehicle speed, and the like. Such traveling state information can be acquired from an in-vehicle computer that controls the traveling state of the vehicle 1. In this embodiment, the control module 134 acquires travel state information. Therefore, the control module 134 corresponds to “information acquisition means”. And the control apparatus 130 sets the interval time corresponding to the acquired driving state to the timer built in itself (step S204). The interval time corresponding to the running state is stored in advance in a ROM (not shown) of the control device 130.

And the control apparatus 130 judges whether the set interval time passed (step S206). When it is determined that the interval time has not elapsed (step S206: NO), the control device 130 is in a standby state while repeating the same determination. On the other hand, when determining that the interval time has elapsed (step S206: YES), the control device 130 acquires a front image while keeping the headlamp 110 lit (step S208). Subsequently, the control device 130 outputs a turn-off signal to the headlamp control unit 112 (step S210). Then, with the headlamp 110 turned off, the control device 130 outputs a trigger signal to the front camera 120 to acquire a front image being turned off (step S212).

Subsequently, the control device 130 determines whether or not a bright spot (a bright spot pair) corresponding to the headlight of the oncoming vehicle exists in the acquired forward image (step S214). As a result, when there is a bright spot of the oncoming vehicle (step S214: YES), the control device 130 determines that there is an oncoming vehicle. Therefore, the control device 130 sets the headlamp 110 to the view restriction mode so as not to bother the driver of the oncoming vehicle (step S216). On the other hand, when there is no bright point of the oncoming vehicle in the front image being turned off (step S214: NO), the control device 130 determines that there is no oncoming vehicle. Therefore, the control device 130 determines whether or not the current illumination mode is the view restriction mode (step S218). If the current illumination mode is the view restriction mode (step S218: YES), the control device 130 sets the headlamp 110 to the view priority mode (step S220). Then, the control returns to step S202, and the control device 130 repeats the series of processes described above. On the other hand, when the current illumination mode is the visibility priority mode (step S218: NO), the control immediately returns to step S202, and the control device 130 repeats the series of processes described above.

In the second modification described above, the headlamp 110 is periodically turned off while the headlight 110 is turned on by the driver of the vehicle 1, and the cycle in which the headlight is turned off corresponds to the traveling state of the vehicle 1. . For this reason, for example, if the oncoming vehicle is equipped with the in-vehicle lighting device 100, the period in which the headlamp is turned off is detected to determine whether the oncoming vehicle is accelerating or decelerating, or turning right. You can get information on whether you are going to turn or turn left. As a result, it is possible to predict the movement of the oncoming vehicle and realize safe driving.

In the second modification described above, the interval time is changed according to the traveling state of the vehicle 1. However, the interval time may be changed according to information such as the vehicle type and model in addition to the driving state or instead of the driving state.

Further, in the second modification described above, the headlamp 110 is turned off for a short time at a constant cycle. However, in addition to the headlamp 110, the rear lamp may be turned off at a cycle according to the traveling state. In this way, if the preceding vehicle is equipped with the in-vehicle lighting device 100, the period in which the rear lamp is turned off is detected, so that information on the traveling state of the preceding vehicle is obtained and safe traveling is realized. It becomes possible to do. For example, if it can be detected that the accelerator pedal of the preceding vehicle is not depressed, it can be predicted that the brake pedal is likely to be depressed next. Therefore, even if the preceding vehicle suddenly stops, it is possible to predict that the brake pedal will be stepped on for an instant, so the possibility of a rear-end collision can be greatly reduced.

The on-vehicle lighting device of the present invention has been described above, but the present invention is not limited to the above-described embodiments and various modifications, and can be implemented in various modes without departing from the scope of the invention.

DESCRIPTION OF SYMBOLS 1 ... Vehicle 100 ... In-vehicle illumination device,
110 ... headlights,
112 ... headlight control unit,
120 ... Front camera,
130 ... control device,
132: Image processing module,
134 ... Control module

Claims

An in-vehicle illumination device that is mounted on a vehicle and illuminates the traveling direction of the vehicle,
A headlamp capable of switching an illumination range in the traveling direction of the vehicle to a predetermined first illumination range and a second illumination range narrower than the first illumination range;
A dimming means for dimming the light intensity of the headlamp to a predetermined intensity or less over a predetermined dimming time;
Image acquisition means for acquiring an image of the traveling direction of the vehicle in a dimmed state in which the intensity of light of the headlamp is dimmed;
Oncoming vehicle determination means for determining the presence or absence of an oncoming vehicle based on an image at the time of dimming that is an image acquired in the dimming state;
An in-vehicle illumination device comprising: an illumination range setting unit that sets an illumination range of the headlamp to the second illumination range when it is determined that the oncoming vehicle is present.
The in-vehicle lighting device according to claim 1,
The image acquisition means is configured to acquire an image of the traveling direction of the vehicle even in a normal state where the intensity of light of the headlamp is not dimmed,
The in-vehicle lighting device includes a dimming determination unit that determines whether to set the dimming state based on a normal-time image that is an image acquired in the normal state,
The in-vehicle lighting device configured to receive the determination result of the dimming determination unit and to enter the dimming state.
The in-vehicle lighting device according to claim 1,
The in-vehicle illuminating device configured so that the dimming means places the headlamp in the dimmed state at a predetermined cycle.
The in-vehicle lighting device according to claim 3,
Comprising information acquisition means for acquiring driving state information which is information relating to the driving state of the vehicle;
The in-vehicle illuminating device configured to set the headlamp to the dimming state at a period according to the traveling state information.
An in-vehicle illumination device that is mounted on a vehicle and illuminates the traveling direction of the vehicle,
A headlamp capable of switching an illumination range in the traveling direction of the vehicle to a predetermined first illumination range and a second illumination range narrower than the first illumination range;
A dimming element for dimming the light intensity of the headlamp below a predetermined intensity over a predetermined dimming time;
An image acquisition element for acquiring an image of the traveling direction of the vehicle in a dimmed state in which the intensity of light of the headlamp is dimmed;
A processing module that determines the presence or absence of an oncoming vehicle based on an image at the time of dimming that is an image acquired in the dimming state;
A vehicle-mounted illumination device comprising: a control module that sets an illumination range of the headlamp to the second illumination range when it is determined that the oncoming vehicle exists.