JP7055563B2 - Light distribution control device - Google Patents

Description

The present invention relates to a light distribution control device used for a headlight of a vehicle such as an automobile, and particularly to a device having an ADB (Adaptive Driving Beam) function.

For the headlights of vehicles such as automobiles, the headlights for traveling (hereinafter referred to as high beam) and the headlights for passing (hereinafter referred to as low beam) are switched so as not to obstruct the view of the preceding vehicle or the oncoming vehicle. When used, a technique has been proposed in which high beam and low beam are automatically switched by detecting the situation in front of the vehicle based on a camera, sonar, radar, or the like.

Furthermore, in recent years, the position of the vehicle in front is specified by detecting the light of the vehicle in front when the high beam is irradiated, and the light distribution of the vehicle in front is performed by forming a shielding area where the light of the high beam does not directly reach the position. There is a vehicle headlight having an ADB (Adaptive Driving Beam) function that reduces glare to the driver (see, for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 2012-180051

However, the above-mentioned conventional technique has the following problems. That is, in the ADB function disclosed in the above-mentioned prior document 1 and the like, when the position of the vehicle in front is specified by detecting the light of the vehicle in front, the light of the high beam is reflected and constant like the reflector of the road sign. There is a risk that an object that produces brightness may be mistakenly recognized as a vehicle in front and included in the shielding area, and it is difficult to accurately shield the vehicle in front from the high beam.

The present invention has been made in view of the above problems, and it is possible to accurately shield an object such as a preceding vehicle in an irradiation range of light such as a high beam and selectively illuminate a range such as the front of the vehicle. It is an object of the present invention to provide a light distribution control device.

In order to achieve the above object, aspects of the present invention include a light source that forms a light beam according to a plurality of light distribution states, an image pickup means that captures an entire range in which a light beam can be formed by the light source, and the plurality of light sources . Based on the image captured by the imaging means in any one of the light distribution states, the light from the light source is distributed so that a shielding range in which the light beam is not formed is included in a part of the entire range in which the light beam can be formed. The light distribution means includes, and the light distribution means sequentially updates the shielding range in any one of the plurality of light distribution states, and the one-dimensional coordinates of two points on the image are set. When one of the one-dimensional coordinates of the two points during the update setting changes in a time of a predetermined time or less, the shielding range is set as a plane including the coordinates set before the update setting. It is a light distribution control device that defines the shielding range as a plane including the changing coordinates when one of the one-dimensional coordinates of the two points being determined and updated changes in a time longer than the predetermined time. ..

As another aspect of the present invention, the vehicle may be provided with the light source and the light distribution means of the light distribution control device on the side surface of the present invention as headlights.

The present invention as described above has the effect of accurately shielding an object such as a preceding vehicle in the light irradiation range and selectively illuminating a range such as the front of the vehicle.

A block diagram showing a configuration of a light distribution control device according to an embodiment of the present invention. The figure for demonstrating the basic operation state of the light distribution control apparatus which concerns on embodiment of this invention. The figure for demonstrating the basic control operation of the light distribution control apparatus which concerns on embodiment of this invention. The figure for demonstrating the basic operation state of the light distribution control apparatus which concerns on embodiment of this invention. Flow chart of operation of light distribution control device which concerns on embodiment of this invention The figure for demonstrating the operation state based on the control of the light distribution control apparatus which concerns on embodiment of this invention. The figure for demonstrating the control operation of the light distribution control apparatus which concerns on embodiment of this invention. The figure for demonstrating the operation state based on the control of the light distribution control apparatus which concerns on embodiment of this invention. The figure for demonstrating the operation state by the comparative example of the light distribution control apparatus which concerns on embodiment of this invention. The figure for demonstrating the operation state by the comparative example of the light distribution control apparatus which concerns on embodiment of this invention.

FIG. 1 is a block diagram showing a configuration of a light distribution control device mounted on a four-wheeled vehicle according to an embodiment of the present invention.

As shown in FIG. 1, in the light distribution control device 1 of the present embodiment, the ECU 10 has a communication device and the like that communicate with other ECUs via a CPU, a memory, and a communication bus 30, and has an input interface (I /). F) It is a means for controlling the operation of the headlight unit 20 by analyzing the input from 11 and the image captured by the vehicle-mounted camera 12. The input I / F 11 is a lighting / switching switch for the high beam light source and the low beam light source, and may be provided as dedicated hardware, or may use car audio, operation switches of the car navigation system, and the like.

The in-vehicle camera 12 is arranged near the roof of the vehicle or the windshield, for example, and is a means for capturing a scene in front of the vehicle as a moving image. The headlight unit 20 is a headlight of an automobile that operates based on the control of the ECU 10 and the input I / F 11, and is a high beam light source having a light distribution control unit 21a and an LED array 21b in which a plurality of LED light sources are arranged in a row. 21 and a low beam light source 22 are included.

As shown in FIG. 2, it is preferable that the angle AV of the vehicle-mounted camera 12 mounted on the vehicle C0 includes all the light beam BL formed by the high beam light source 21 of the headlight unit 20. The imaging range RV in front of the vehicle C0 of the vehicle-mounted camera 12 includes the irradiation range of the high beam light source 21 at least in the horizontal direction.

In the above configuration, the LED array 21b corresponds to the light source of the present invention, the in-vehicle camera 12 corresponds to the image pickup means of the present invention, and the combination of the ECU 10 and the light distribution control unit 21a corresponds to the light distribution means of the present invention.

Since the light distribution control device of the present embodiment has the above configuration, the image included in the luminous flux of the high beam light source 21 captured by the vehicle-mounted camera 12 is analyzed, and the speed of the object included in the image is analyzed. By discriminating between the preceding vehicle and the like and other objects based on the above, the LED array 21b is selectively lit and distributed so as to include a shielding range in which the light flux including the preceding vehicle and the like is not formed.

That is, as a basic operation, the headlight unit 20 is set to the high beam state by the operation of the high beam light source 21 by the input to the input I / F 11 by the driver or a third party, and then the scene in front of the vehicle is viewed by the in-vehicle camera 12. Take an image. The moving image captured by the vehicle-mounted camera 12 is output to the ECU 10 and analyzed in frame units to identify the horizontal position of the oncoming vehicle or the target vehicle, which is the preceding vehicle, within the imaging range in the frame. As one specific example, as shown in FIG. 3, the distribution of the luminance information of the image PV is calculated for each predetermined unit or processing pixel unit, and the image PV whose luminance is equal to or higher than a predetermined threshold value is used as the position coordinate. Plot on the X-axis in the figure, which is the horizontal direction of, and store it in its own memory. In the example, the position of the rightmost taillight TLR of the preceding vehicle C1 is plotted on the right side coordinate Xr, and the position of the leftmost taillight TLL is plotted on the left side coordinate Xl0.

In the headlight unit 20, based on the right side coordinate Xr and the left side coordinate Xl0 calculated by the ECU 10, a range on the X axis sandwiched between the respective coordinates is defined as a shielding region, and the LED light source 21b stops emitting light. Then, control is performed so that only other LED light sources emit light. As a result, as shown in FIG. 4, the luminous flux BL due to the light distribution of the high beam light source 21 of the headlight unit 20 is selectively used as the light distribution regions AL1 and AL2 adjacent to the left and right of the shielding region AD including the preceding vehicle C1. It is formed in the above, and glare to the preceding vehicle C1 is suppressed.

Next, the operation of the light distribution control device 1 under the control of the ECU 10 and the light distribution control unit 21a will be described in detail with reference to the flowchart of FIG. Similar to the above-mentioned basic operation, the vehicle-mounted camera 12 captures a scene in front of the vehicle during the operation of the high beam light source 21 (S10), and the ECU 10 is on the X-axis in frame units from the moving image captured by the vehicle-mounted camera 12. The position coordinates are extracted (S11). At this time, as shown in FIG. 6, when there is a road sign having a reflector F in front of the vehicle C0, the reflector F reflects the headlight of the vehicle C0 to have brightness information equal to or higher than the threshold value. Become. Therefore, as shown in FIG. 7, in the image PV to be analyzed by the ECU 10, the positions of the right coordinate Xr of the preceding vehicle C1 and the position of the reflector F located to the left of the left coordinate Xl0 are X as new left coordinate Xl1. Plotd on the axis.

Next, the ECU 10 calculates the time change from the position of each frame of the left coordinate Xl1 extracted in S11 (S12), and compares the magnitude with a predetermined threshold value stored in advance in itself (S13). Here, the threshold value is determined by the relative velocity of the object within the range of the image PV with respect to the vehicle C0. The relative speed of an object fixed on the external environment in the image PV (hereinafter referred to as a fixed object) is determined according to the moving speed of the vehicle C0, while the relative speed of the preceding vehicle C1 is the speed of the preceding vehicle itself. Since it is determined including the relative velocity, it is generally smaller than the relative velocity of the fixed object. Based on this, the present invention separates the preceding vehicle C1 from other fixed objects according to the magnitude of the time change of the left coordinate.

Specifically, when the time change is less than the threshold value, it can be estimated that the moving speed of the left side coordinate Xl1 is the speed of the preceding vehicle C1, and in this case, the ECU 10 has the right side coordinate Xr and the left side coordinate Xl1 plotted in S11. The shielding area is determined based on (S14), the LED light source to be emitted in the LED array 21b is selected, and the high beam light source 21 of the headlight unit 20 is distributed (S15).

In this case, the position of the reflector F of the road sign shown in FIG. 6 is included as the position of the new preceding vehicle adjacent to the left side of the vehicle C1, and the position of the reflector F similar to the state shown in FIG. 9 described later. And the control operation includes the position of the vehicle C1 as a shielding area.

On the other hand, when the time change is equal to or greater than the threshold value, the moving speed of the left coordinate Xl1 is higher than the relative speed of the preceding vehicle C1, so that it is estimated to be the relative speed of the fixed object. Based on this, the ECU 10 determines the shielding area based on the right coordinate Xr plotted in S11 and the left coordinate Xl0 plotted last time in the basic operation (S16), selects the LED light source to emit light in the LED array 21b, and selects the headlight unit. The light distribution of the 20 high beam light sources 21 is performed (S15).

In this case, as shown in FIG. 8, during the travel distance D1 after the vehicle C0 plots the left side coordinate Xl1 of the reflector F of the road sign shown in FIG. 6, the high beam light source 21 of the headlight unit 20 The light source BL due to the light distribution maintains a state selectively formed as the light distribution regions AL1 and AL2 adjacent to the left and right of the shielding region AD including only the preceding vehicle C1 by excluding the reflector F of the road sign. After that, the process returns to S10 and the following steps are repeated.

By the above operation, it is possible to selectively illuminate a range such as the front of the vehicle by separating the high beam light source 21 of the headlight unit 20 and the fixed object in the external environment from the preceding vehicle and accurately shielding the preceding vehicle. Will be.

As a comparative example, the operation when the separation step according to S12 to S13 is omitted is as follows. That is, in the operation of S11, the ECU 10 uses the right-side coordinate Xr detected on the X-axis as the right-side coordinate from the image PV, and the left-side coordinate Xl1 detected on the X-axis as the left-side coordinate. Plot each. Therefore, as shown in FIG. 9, the luminous flux due to the light distribution of the high beam light source 21 of the headlight unit 20 distributed according to the shielding region AD based on these is formed only by the light distribution region AL1 on the right side of the vehicle C1. Will be done.

Further, when the vehicle C0 continues to travel, as shown in FIG. 10, the reflector F of the road sign is out of the imaging range of the in-vehicle camera 12, so that the ECU 10 moves the preceding vehicle from the image PV in the operation of S11. The positions of the left and right taillight TLRs and taillights TLL of C1 are plotted again with the right side coordinate Xr and the left side coordinate Xl0. Therefore, as shown in FIG. 10, the luminous flux due to the light distribution of the high beam light source 21 of the headlight unit 20 distributed according to the shielding region AD based on these is again on the left and right of the shielding region AD including the preceding vehicle C1. It is selectively formed as adjacent light distribution regions AL1 and AL2.

In the operation of the above comparative example, the headlight unit is in the period from the position Y0 to the distance D3 when the vehicle C0 travels from the position Y0 to the distance D3 when the road sign having the reflector F shown in FIG. 6 is imaged by the vehicle-mounted camera 12. The high beam light source 21 of 20 shields a region to be originally light-distributed, and changes the light distribution region to cause flicker in the driver's view.

On the other hand, in the present embodiment, by defining the plot of the left coordinate based on the time change, the fixed object in the outside environment and the preceding vehicle are separated, the preceding vehicle is accurately shielded, and the light distribution region is covered. It realizes safe driving by suppressing changes and reducing the risk of causing flicker in the driver's field of vision.

As described above, according to the light distribution control device according to the embodiment of the present invention, it is possible to accurately shield an object such as a preceding vehicle in the light irradiation range and selectively illuminate a range such as the front of the vehicle. It becomes. As a result, when used as a headlight of a vehicle, it is possible to secure a view of an area necessary for driving while suppressing glare to the vehicle in front, and to drive safely.

Further, according to the light distribution control device of the present embodiment, the shielding range is set only by plotting two points at the one-dimensional coordinates in the captured image. This makes it possible to simplify the configuration on the hardware and realize the ADB function in a low-cost configuration in which the burden of software processing is reduced.

However, the present invention is not limited to the above embodiment.

In the above description, the ECU 10 which is the light distribution means of the present invention handles the time change of the left side coordinate on the X axis as the position coordinate of the image captured by the vehicle-mounted camera 12, but the time of the right side coordinate. It may deal with change. In this case, it is suitable when the present invention is applied to the separation between the oncoming vehicle and the fixed object and the traveling on the road where the traveling lane is on the right side. Further, it may handle time changes of both the left side coordinate and the right side coordinate.

Further, in the above description, the light source of the present invention is the LED array 21b, but the light source of the present invention includes a shielding range in which the light flux is not formed in a part of the entire range in which the light flux can be formed by the light distribution means. The light may be distributed so as to be, and is not limited by other specific configurations. Therefore, the light from a single light source may be distributed by performing optical processing such as diffusion, refraction, and shielding.

Further, in the above description, the example incorporated into the vehicle which is the automobile of the present invention is used, but the present invention may be applied to a two-wheeled vehicle, a ship, a train, an aircraft or other moving body.

As described above, the present invention is a light distribution control device, which comprises a light source that forms a light beam according to a plurality of light distribution states, an image pickup means that captures an image of the entire range in which the light beam can be formed by the light source, and the above -mentioned. Based on the image captured by the imaging means in any one of the plurality of light distribution states, the light from the light source is emitted so that a shielding range in which the light beam is not formed is included in a part of the entire range in which the light beam can be formed. The light distribution means includes a light distribution means for distributing light, and the light distribution means is set by sequentially updating the shielding range in any one of the plurality of light distribution states. It is defined as a plane including dimensional coordinates, and when one of the one-dimensional coordinates of the two points during the update setting changes in a time of a predetermined time or less, the shielding range includes the coordinates set before the update setting. When one of the one-dimensional coordinates of the two points being set to be updated changes in a time longer than the predetermined time, the shielding range may be defined as a plane including the changing coordinates. , Other specific purposes, uses, and configurations are not limited.

Therefore, the present invention may be carried out as if various modifications were made to the above-described embodiments, including those described above, as long as the present invention does not deviate from the gist thereof.

The present invention as described above has the effect of accurately shielding an object such as a preceding vehicle in the light irradiation range and selectively illuminating a range such as the front of the vehicle. For example, a four-wheeled vehicle. It is useful in application to the ADB function of vehicles such as.

1 Light distribution control device 10 ECU
11 Input I / F
12 In-vehicle camera 20 Headlight unit 21 High beam light source 21a Light distribution control unit 21b LED array 22 Low beam light source 30 Communication bus C0, C1 Vehicle C1 Leading vehicle D1 Travel distance F Reflector D3 Distance AD Shielding area BL Luminous flux AL1, AL2 Area AV angle PV image TLL, TLR taillight Xl0, Xl1 left side coordinate Xr right side coordinate

Claims (1)

A light source that forms a luminous flux according to multiple light distribution states ,
An imaging means that captures the entire range in which a luminous flux can be formed by the light source, and
Based on the image captured by the imaging means in any one of the plurality of light distribution states, the light from the light source includes a shielding range in which the luminous flux is not formed in a part of the entire range in which the luminous flux can be formed. Equipped with a light distribution means to distribute the light
The light distribution means defines the shielding range as a plane including one-dimensional coordinates of two points on the image, which is sequentially updated and set in any one of the plurality of light distribution states . ,
When one of the one-dimensional coordinates of the two points during the update setting changes in a time of a predetermined time or less, the shielding range is defined as a plane including the coordinates set before the update setting.
When one of the one-dimensional coordinates of the two points during the update setting changes in a time longer than the predetermined time, the shielding range is defined as a plane including the changing coordinates.
Light distribution control device.

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