JPH09113264A - Device for notifying vehicle approaching from rear lateral side - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device for notifying rear vehicle approaching from rear lateral side which can make operation at a high speed and uses a cost-reduced processing section by making the removal of the background of a rear vehicle approaching from rear lateral side or extraction of the area containing the picture of the vehicle unnecessary. SOLUTION: When a rear vehicle approaching its own vehicle from one side enters the visual field of a device for notifying rear vehicle approaching from one side, the light made incident to the device forms images on first and second picture element groups 102 and 107 through first and second lenses 101 and 106, respectively and the picture signals of the images are inputted to a distance computing section 110 from first and second signal outputting sections 104 and 109. The section 110 calculates the distance to the rear vehicle and a discriminating and alarming section 111 issues an alarm when the rear vehicle excessively approaches its own vehicle. The picture element groups 102 and 107 are arranged nearly parallel to a white line, etc. Therefore, the background of the approaching vehicle from rear lateral side can be eliminated from the photographing extent of the device.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rear side vehicle alarm device for detecting and notifying when another vehicle approaches the rear side while the vehicle is traveling.

[0002]

2. Description of the Related Art Conventionally, as a distance measuring device for measuring a distance to a measuring object, Japanese Patent Application Laid-Open No. 50-138825 discloses a passive triangulation type distance meter. this is,
It has two sets of optical systems and a light receiving part, detects the light entering from each optical system in each light receiving part, converts it into a brightness signal, compares each brightness signal while shifting and calculates a correlation. Then, the distance is calculated from the shift amount when the correlation is the largest.

About this passive triangulation range finder,
This will be described with reference to FIGS. 26 and 27. As shown in FIG. 26, a first lens 601 as a first optical system is provided so as to face the measurement target 600, and the first lens 601 is provided.
At the focal position of the first light receiving element 602 as the first light receiving portion
Is arranged. Along with the first lens 601 and the first light receiving element 602, the second lens 605 as the second optical system and the second light receiving element 606 as the second light receiving unit are arranged.
Is arranged. Then, from the measurement target 600, the first
The light passing through the lens 601 passes through the first light receiving element 602 and the second light receiving element 602.
The light passing through the lens 605 is input to the second light receiving element 606, and the first lightness signal 603 and the second lightness signal 607 are obtained. The first brightness signal 603 and the second brightness signal 607 are calculated to calculate the distance to the measurement target 600.

FIG. 27 shows an object 600 to be measured and a first lens 6.
It is a figure which shows the positional relationship of 01, the 1st light receiving element 602, the 2nd lens 605, and the 2nd light receiving element 606. The position of the measurement target 600 is 600 ′, the optical center position of the first lens 601 is 601 ′, the optical center position of the second lens 605 is 605 ′, and the distance to the measurement target 100 is Dj,
The base line length between the position 601 'and the position 605' is B. The intersection between the optical axis of the second lens 605 and the second light receiving element 606 is 606 ′, and the distance between the position 605 ′ and the intersection 606 ′ is f. f represents the focal length of the second lens 605. The position on the second light receiving element 606 where the light from the measurement target 600 connects the images is 608 ′, and the parallax between the positions 606 ′ and 608 ′ is R. Here, the triangle 600'-601'-605 '
And the triangles 605'-606'-608 'are similar, Dj / B = f / R holds.

Therefore, the distance D to the object 600 to be measured
j is obtained by calculating Dj = B · f / R. Here, the baseline length B,
Since the focal length f can be measured in advance, the distance Dj can be calculated if the parallax R is known. Parallax R
Is the second brightness signal 60 with respect to the first brightness signal 603.
7 is shifted and compared to obtain the correlation, and the correlation is obtained from the shift amount when the correlation is the largest. The passive triangulation type rangefinder as described above can be used as a vehicle detection sensor for detecting a vehicle approaching from the rear side.

[0006]

However, when the light receiving portion of the passive triangulation type rangefinder is arranged horizontally or vertically, for example, a white line on the road surface, a guardrail or a roadside can be used in addition to the vehicle on the rear side. Backgrounds such as buildings are within the shooting range. That is, description will be made with reference to FIGS. 28 to 31 showing a case where the passive triangulation type rangefinder is mounted on the vehicle 650. 28 and 29 are diagrams showing a shooting range when the light receiving unit is arranged in the horizontal direction, and a relationship between the shooting target and the light receiving range. In this case, the white line 610 and the guardrail 611 on the road surface are included in the shooting range 651.
Further, the white line 610 and the guard rail 611 are also included in the light receiving range 652 which is a projected light receiving element. 30 and 31 are diagrams showing a photographing range when the light receiving unit is arranged in the vertical direction, and a relationship between the photographing target and the light receiving range. Also in this case, the white line 610 and the guard rail 611 are included in the photographing range 655 and the light receiving range 656.

When the contrast of the background is higher than that of the rear side vehicle, the distance to the background is measured. Therefore, when the rear side vehicle is detected, it is necessary to remove the background or extract the region in which the rear side vehicle is present, which causes a problem of complicated processing.

The present invention has been proposed in view of the above circumstances and does not require removal of the background of another vehicle approaching from the rear side or extraction of a region in which the rear side vehicle appears, and the processing is simple. Another object of the present invention is to provide a rear side vehicle notification device.

[0009]

In order to achieve the above object, a rear side vehicle alarm system according to the present invention has a plurality of pixels arranged on a straight line or a plurality of parallel straight line groups including the straight line. The first pixel group and the second pixel group, which are formed by arranging the first image capturing unit and the second image capturing unit at the focal position, are arranged substantially parallel to the road surface trajectory, and the first pixel unit and the second pixel unit are arranged. A first signal output section and a second signal output section are provided in the pixel group and the second pixel group, and the first signal output section and the second signal output section are connected to the rear side via a distance calculation section. This is connected to a judgment and warning unit that judges whether another vehicle approaching from the side approaches too much and issues a warning.

The judgment warning unit may include a contrast calculation unit for calculating the contrast, and may be configured not to issue an alarm when the contrast of the image signal calculated by the contrast calculation unit is smaller than a predetermined value.

The first pixel group and the second pixel group leave the image charges accumulated in the first pixel group and the second pixel group, respectively, and additionally store new image charges. And a second carry-over storage unit, a contrast calculation unit for calculating the contrast of the image signal is connected to the second carry-over storage unit, and the image charge is calculated according to the contrast calculated by the contrast calculation unit. It is also possible to adjust the time and the number of carry-over accumulations of.

Further, the first pixel group and the second pixel group are each formed by arranging a plurality of pixels in a two-dimensional manner, and are provided in the subsequent stages of the first signal output section and the second signal output section. The image signal of the photographic screen imaged in the first pixel group and the second pixel group is partitioned into a plurality of partition parts including a predetermined number of pixels in the direction parallel to the road surface trajectory, and It is also possible to provide a first averaging unit and a second averaging unit that average the pixel signals to measure the distance to another vehicle.

[0013]

In the rear side vehicle alarm system of the present invention, a plurality of pixels are arranged on a first pixel group and a second pixel group arranged on a straight line or on a plurality of parallel straight line groups including the straight line. , First
Since the first pixel group is arranged substantially parallel to the road surface trajectory in forming images by the photographing means and the second photographing means, the background of another vehicle approaching from the rear side is removed from the photographing range. It Then, the first image signal and the second image signal corresponding to each pixel of the first pixel group and the second pixel group are output from the first signal output unit and the second signal output unit, respectively. Based on the first image signal and the second image signal, the distance calculation unit calculates the distance to the other vehicle, and the determination alarm unit determines that the vehicle is too close to the other vehicle and issues an alarm.

If the judgment warning unit judges that the contrast of the image signal calculated by the contrast calculation unit is smaller than the predetermined value, no warning is issued.

In addition, the first carry-over accumulation unit and the second carry-over accumulation unit leave the image charges accumulated in the first pixel group and the second pixel group, respectively, and additionally accumulate new image charges. If the configuration is such that the time and the number of carry-over accumulations of image charges are adjusted according to the contrast of the image signal calculated by the contrast calculation unit, the contrast difference that occurs in the background becomes extremely small, so the distance to the background Is prevented from being erroneously measured.

Further, the two-dimensional image of the photographing screen imaged on the first pixel group and the second pixel group by the first averaging unit and the second averaging unit is set to the road surface trajectory. In the parallel direction, partition into a plurality of partition parts including a predetermined number of pixels,
When the pixel signals in the section are averaged to measure the distance to other vehicles, even if the first pixel group and the second pixel group are not arranged parallel to the white line on the road, False measurement of distance is prevented.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a rear side vehicle alarm system according to the present invention will be described below in detail with reference to the drawings. First, a first embodiment will be described with reference to FIGS.
FIG. 1 is a block diagram showing the configuration of the first embodiment. At the focus position of the first lens 101 as the first photographing means,
First pixel group 10 in which a plurality of pixels 103 are arranged on a straight line
2 is the second lens 106 as the second photographing means.
A second pixel group 107 in which a plurality of pixels 108 are arranged on a straight line is arranged at the focal position of. First pixel group 10
2 has a first signal output unit 104, the second pixel group 107 has a second signal output unit 109, and the first signal output unit 10
The fourth signal output unit 109 and the second signal output unit 109 are connected to the distance calculation unit 110, respectively. The above is the same as the configuration of the passive triangulation type rangefinder. Then, the distance calculation unit 110
Further, a judgment warning unit 111 that judges whether the other vehicle is approaching too much and issues a warning is connected.

FIG. 2 shows a first lens 101 and a second lens 1.
6 is a diagram showing an arrangement of the first pixel group 102, the second pixel group 107, and the like. First lens 101 and second
The lenses 106 are attached to the front surface of the case 113 at predetermined intervals, and the first pixel group 102 and the second pixel group 107 are attached.
Is housed inside a case 113 to form a photographing unit 112.

FIG. 3 is a view showing an installation example of the first lens 101 and the second lens 106. In the first embodiment, the first lens 101 and the second lens 106 are installed rearward in the center inside the front pillar 121 that supports the front glass 120 of the vehicle 100. As a result, the driver's view is not obstructed and it is not necessary to take waterproof measures. Here, the first pixel group (not shown) arranged at the focal position of the first lens 101 is arranged substantially parallel to the road surface trajectory.

FIG. 4 is a diagram showing the photographing range, and FIG. 5 is a diagram showing the relationship between the photographing target and the light receiving range. First pixel group 1
As shown in FIG. 5, the light receiving range 102 ′ projected and displayed with 02 is substantially parallel to the white line 610 and the guardrail 611. As a result, a triangular imaging range 115 is formed in which the line segment 116 at the tip is substantially parallel to the white line 610 and the guardrail 611.

In the above structure, when another vehicle enters the photographing range 115 from the rear side, the light incident on the first lens 101 from the vehicle is imaged on the first pixel group 102, In addition, the light incident on the second lens 106 is
An image is formed on the pixel group 107 of. The image of the first pixel group 102 and the image of the second pixel group 107 are converted into lightness signals, and are output from the first signal output unit 104 and the second signal output unit 109, respectively. The first image signal output from the first signal output unit 104 and the second image signal output from the second signal output unit 109 are input to the distance calculation unit 110, respectively. Distance calculator 11
0 calculates the distance to another vehicle based on the first image signal and the second image signal, and outputs the calculated value to the determination warning unit 111.

Based on the distance information from the distance calculation unit 110, the judgment warning unit 111 judges whether another vehicle is too close, and if it is too close, a warning is given to the driver. To do. If you are not too close,
No alarm is issued. As the warning, there are a visual warning lamp and a buzzer that acts on the hearing.

By the way, depending on the running state of the vehicle 100,
As shown in FIG. 6, a white line 61 on the road surface covers the shooting range 115.
There are cases where 0 or the like crosses and a white line 610 falls within the light receiving range 102 '. In this case, since the output level G of the image signal by the white line 610 is gentle and the difference in contrast is small as shown in FIG. 7, it is hardly affected by the detection of other vehicles approaching from the rear side. Absent.

As described above, according to the first embodiment, the first pixel group 102 is arranged substantially parallel to the white line 610 and the guardrail 611 along the traveling direction of the vehicle, so that the background of other vehicles is improved. The white line 610, the guardrail 611, the building, and the like are outside the photographing range 115. Therefore, it becomes unnecessary to perform processing such as background removal or extraction of an area in which another vehicle is captured, which makes it possible to speed up the calculation and reduce the cost of the processing unit.

FIG. 8 is a diagram showing a modified example of the photographing section in the first embodiment. A plurality of pixels 152 and 154 are arranged on a plurality of parallel straight line groups, respectively.
First and second pixel groups 153 are formed. The other structure is the same as that of the first embodiment. Thus, by performing a filtering process such as a moving average between the pixel columns arranged on a plurality of parallel straight lines, the influence of noise can be prevented and the detection accuracy of other vehicles can be improved.

9 to 11 are views showing other examples of installation of the first lens 101 and the second lens 106. FIG.
Shows an example in which the first lens 101 and the second lens 106 are installed inside the rearview mirror 161 installed on the driver's seat side door 160. As a result, the first lens 101 and the second lens 106 do not hinder the driver's view, and
It can be molded integrally with the rearview mirror 161.

FIG. 10 shows an example in which the first lens 101 and the second lens 106 are mounted near the intersection of the driver side front pillar 121 and the ceiling 170 in the vehicle interior. As a result, the heights of the first lens 101 and the second lens 106 from the road surface are secured, and the detection range for the rear side vehicle can be expanded.

FIG. 11 shows an example in which the first lens 101 and the second lens 106 are mounted near the rear-view mirror 161 installed on the driver side door 160 in the passenger compartment. In this case, because of the rear view mirror 161, the window glass 180
Attach so that you can shoot from the part where the raindrops are hard to attach. As a result, the shooting range is rarely obstructed by raindrops, and measures against raindrops such as wipers and air curtains are not required.

Next, a second embodiment will be described. The second embodiment is an effective example when the host vehicle crosses a white line due to a lane change or the like. FIG. 13 is a diagram showing a photographing range when changing lanes, and FIG. 14 is a diagram showing a relationship between a photographing target and a light receiving range. When changing lanes, as shown in FIG.
00 moves and tilts from a state parallel to the white line 610 and the guardrail 611, so that the line segment 204 at the tip of the photographing range 203 intersects with the white line 610, and as shown in FIG.
A white line 610 is included in the light receiving range 102 '.

FIG. 12 is a block diagram showing the configuration of the second embodiment. In the second embodiment, in addition to the configuration of FIG. 1 in the first embodiment, a contrast calculation unit 201 is provided between the second signal output unit 109 and the judgment warning unit 202, and the calculation by the contrast calculation unit 201 is performed. When the contrast of the received light receiving range 102 'is smaller than a predetermined value, the judgment warning unit 20
The warning by 2 is prohibited. The other structure is the same as that of the first embodiment.

For example, in the case where a road with a lane width of 3.5 m is changed in one second while traveling at a speed of 60 km / h, the angle is as small as 11.8 degrees. Therefore, the white line 610 indicates the light receiving range 10 as shown in FIG.
The output level G of the image signal becomes a smooth curve as shown in FIG. In this way, when the contrast of the image signal calculated by the contrast calculation unit 201 is smaller than the predetermined value, the judgment alarm unit 202 is prohibited from issuing an alarm. As a result, even if the white line 610 and the like enter the shooting range 203 and the distance is measured when the lane is changed, no alarm is issued.

According to the second embodiment, even if the white line 610, the guardrail 611, etc. enter the photographing range 203 when the lane is changed, etc., if the contrast calculated by the contrast calculating unit 201 is smaller than a predetermined value, Since no alarm is issued, it is possible to prevent a false alarm caused by measuring the distance to the white line 610.

Next, a third embodiment will be described. The third embodiment is an effective example when a background such as a white line or a guardrail is included in the shooting range, and there is a risk that the distance to the background will be measured due to a break in the white line, a joint of the guardrail, a support, or the like. Is. FIG. 17 is a diagram showing a shooting range,
FIG. 18 is a diagram showing the relationship between the photographing target and the light receiving range.
Depending on road conditions, etc., as shown in FIG.
0 moves toward the guardrail 611, and the shooting range 305
The line segment 306 at the tip of the
As shown in FIG. 18, the guardrail 611 may enter the light receiving range 102 '. In this case, the output level G of the image signal is as shown in FIG. 19, and there is a large difference in contrast between the portion formed by the support 611A and the other portion. Therefore, the distance to the background guardrail 611 may be measured.

FIG. 16 is a block diagram showing the configuration of the third embodiment. The third embodiment is a charge coupled device (CCD).
The first carry-over between the first pixel group 102 and the first signal output section 104 by the above, and between the second pixel group 107 and the second signal output section 109 by the charge coupled device (CCD). Accumulation unit 301 and second carry-over accumulation unit 302
And a contrast calculation unit 303 is connected to the second signal output unit 109.

Here, the first carry-over storage unit 301 and the second carry-over storage unit 302 are the first signal output unit 1
04 and the second signal output unit 109 output image signals, the first pixel group 102 and the second pixel group 1
The charges accumulated in 07 are not cleared but left, and new image charges are additionally accumulated. Further, the contrast calculation unit 303 checks the contrast of the image signal up to the previous shooting. Then, the value of the contrast calculated by the contrast calculation unit 303 is fed back to the second carry-over accumulation unit 303, and upon receiving the feedback signal, a signal is output from the second carry-over accumulation unit 303 to the first carry-over accumulation unit 301. In this way, the carry-over accumulation timing is matched. The other structure is the same as that of the first embodiment.

FIG. 20 is a diagram showing the relationship between the object to be photographed and the light receiving area while the vehicle is running. Since the host vehicle 100 is running, the state where the support 611A of the guard rail 611 and the joint 611B are moving is shown. Shows. This is the same as the movement of the support 611A and the like within the light receiving range 102 ′ because it takes a predetermined time to accumulate the image charges in the first pixel group 102 and the second pixel group 107 in FIG. is there. Then, for example, the own vehicle 100
However, when traveling at a speed of 60 km / hour, it moves 0.5 m in 30 microseconds. Therefore, as shown in FIG. 21, the output level G of the image signal is low in the part by the support 611A, and the difference in contrast with other parts is small.

As a result, it can be understood that if the accumulation time for the first pixel group 102 and the second pixel group 107 is lengthened, the influence of the background will be reduced in detecting the distance to another vehicle. However, if you just increase the accumulation time, the amount of accumulated light will be too large and will exceed the limit.
In addition, an extra mechanism is required to adjust the amount of light with the iris of the optical unit.

Therefore, the first carry-over accumulation unit 301 and the second carry-over accumulation unit 302 carry out carry-over accumulation In of the image signal several times as shown in FIG. Further, the time Tse from the start of the carry-over accumulation to the end is adjusted according to the contrast of the image signal calculated by the contrast calculation unit 303, and the accumulation time Tin of the carry-over accumulation is adjusted according to the light amount. One carry-over accumulation time Tin is fixed, and the number of carry-over accumulations and the carry-off accumulation pause time are variable.

The contrast calculation unit 303 checks the contrast of the image signals up to the previous photographing. If the difference in the background contrast is large, the pause time of the carry-over accumulation is lengthened, and if the difference in the contrast is small, the carry-over accumulation is performed. Shorten the rest time. Also, check the light intensity from the image signals up to the previous shooting, and if the light intensity is low, increase the number of carry-over accumulations, and if the light intensity is high,
It reduces the number of carry-over accumulations. This allows
The contrast difference that occurs in the background is so small that measuring the distance to that background is prevented.

As described above, according to the third embodiment, the first carry-over accumulation unit 301 is used according to the contrast and the light amount of the image signal calculated by the contrast calculation unit 303.
Since the time and the number of times the image charges are carried over and accumulated by the second carry-over accumulation unit 302 is adjusted, a background such as a white line or a guardrail is not included in the shooting range, and the distance to the background is not measured. It is possible to reliably measure the distance from the rear side to another vehicle approaching.

Next, a fourth embodiment will be described. In the fourth embodiment, the distance to the background is prevented from being erroneously measured even if the first pixel group and the second pixel group are not arranged parallel to the white line on the road. Is. FIG.
FIG. 25 is a diagram showing a photographing range, and FIG. 25 is a diagram showing a relationship between a photographing target and a light receiving range. As shown in FIG. 24, the shooting range 4
A white line 610 and a guardrail 611 are included in the area 11. As shown in FIG. 25, the light receiving range 412 has a rectangular shape, and the long side 413 or the short side 414 of the light receiving range 412 is the vehicle 10.
This is a state in which the white line 610 and the guard rail 611 along the traveling direction of 0 are not arranged in parallel.

FIG. 23 is a block diagram showing the structure of the fourth embodiment. In the fourth embodiment, instead of the first pixel group 102 and the second pixel group 109 of FIG. 16 in the third embodiment, a first pixel group 401 in which pixels are arranged two-dimensionally
And a second pixel group 402 are provided, and a first average processing unit 407 and a second average processing unit are provided between the first signal output unit 405 and the second signal output unit 406 and the distance calculation unit 409. 408 are provided respectively. The other structure is the same as that of the third embodiment.

In the above structure, when another vehicle comes into the photographing range 411 from the rear side, the first lens 10
The first and second lenses 106 allow the first pixel group 401
Then, a two-dimensional image is formed on each of the second pixel group 402. First pixel group 401 and second pixel group 40
Each of the two-dimensional images on 2 is the first carry-over accumulation unit 4
03 and the second carry-over accumulation unit 404
Signal output unit 405 and second signal output unit 406 to first average processing unit 407 and second average processing unit 408.
Is output to

The first averaging unit 407 and the second averaging unit 408, as shown in FIG.
The two-dimensional image is partitioned into a plurality of rectangular partition parts 415 including a predetermined number of pixels in a direction parallel to the white line 610 and the like. Then, the pixel signals in each partition unit 415 are averaged and the value is output to the distance calculation unit 409. Here, since the pixel signals in each partition 415 are averaged to measure the distance, the influence of the background contrast can be removed.

The distance calculation unit 409 is the first average processing unit 4
07 and the value of the pixel signal input from the second averaging unit 408, the distance to another vehicle is calculated, and the calculated value is output to the determination warning unit 111. Then, the judgment warning unit 111 gives a warning when another vehicle is approaching too much.

As described above, according to the fourth embodiment, the first averaging unit 407 and the second averaging unit 408 cause the first signal output unit 405 and the second signal output unit 406 to operate. The image signal of the output two-dimensional image is converted into white line 6
The distance is calculated by partitioning into a plurality of partition parts 415 including a predetermined number of pixels in a direction parallel to 10 and the like and averaging pixel signals in each partition part 415. As a result, the influence of the background contrast can be removed, so that it is possible to eliminate the processing such as the removal of the background or the extraction of the area in which another vehicle appears.

[0047]

As described above, according to the rear side vehicle alarm system of the present invention, a plurality of pixels are arranged on a straight line or on a plurality of parallel straight line groups including the straight line. When forming images on the pixel group and the second pixel group by the first photographing means and the second photographing means, respectively, the first pixel group and the second pixel group are arranged substantially parallel to the road surface trajectory. Therefore, the background of another vehicle approaching from the rear side is removed from the shooting range. Therefore, the processing such as the removal of the background or the extraction of the area where the vehicle on the rear side is captured is unnecessary, the processing is simplified, the calculation speed is increased, and the cost of the processing unit is reduced.

Further, if the judgment warning unit judges that the contrast of the image signal calculated and input by the contrast calculation unit is smaller than the predetermined value, no warning is issued, so that a false alarm can be prevented.

Further, the first pixel group and the second pixel group leave the image charges accumulated in the first pixel group and the second pixel group respectively, and additionally accumulate new image charges. And a second carry-over storage unit, a contrast calculation unit for calculating the contrast of the image signal is connected to the second carry-over storage unit, and the image charge is calculated according to the contrast calculated by the contrast calculation unit. If the configuration is such that the time and number of carry-over accumulations are adjusted, the difference in contrast that occurs in the background becomes extremely small, so erroneous measurement of the distance to the background is prevented, and other vehicles approaching from the rear side The distance to can be measured reliably.

Further, each of the first pixel group and the second pixel group is formed by arranging a plurality of pixels in a two-dimensional manner, and the first pixel output section and the second signal output section are provided at the subsequent stages. The image signal of the photographic screen is divided into a plurality of divisions including a predetermined number of pixels in the direction parallel to the road surface trajectory, and the pixel signals in the divisions are averaged to measure the distance to another vehicle. If the 1st averaging section and the 2nd averaging section are provided, the distance to the background will be incorrect even if the 1st pixel group and the 2nd pixel group are not arranged in parallel to the white line on the road. Measurement is prevented. Therefore, the processing such as the removal of the background or the extraction of the area where the vehicle on the rear side is captured is unnecessary, the processing is simplified, the calculation speed is increased, and the cost of the processing unit is reduced.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a first embodiment.

FIG. 2 is an external perspective view of a photographing unit according to the first embodiment.

FIG. 3 is a diagram showing an installation position of a lens of the first embodiment.

FIG. 4 is a diagram showing a shooting range in the first embodiment.

FIG. 5 is a diagram showing a relationship between a subject to be photographed and a light receiving range in the first embodiment.

FIG. 6 is a diagram showing a relationship between a white line and a light receiving range in the first embodiment.

FIG. 7 is a diagram showing the output level of the image signal in the state of FIG. 6 in the first embodiment.

FIG. 8 is a diagram illustrating a modified example of the image capturing unit according to the first embodiment.

FIG. 9 is a diagram showing a modification of the installation position of the lens of the first embodiment.

FIG. 10 is a diagram showing a modification of the installation position of the lens of the first embodiment.

FIG. 11 is a diagram showing a modification of the installation position of the lens of the first embodiment.

FIG. 12 is a block diagram showing a configuration of a second exemplary embodiment.

FIG. 13 is a diagram showing a shooting range in the second embodiment.

FIG. 14 is a diagram showing a relationship between an imaging target and a light receiving range in the second embodiment.

FIG. 15 is a diagram showing an output level of an image signal in the second embodiment.

FIG. 16 is a block diagram showing a configuration of a third exemplary embodiment. .

FIG. 17 is a diagram showing a shooting range in the third embodiment. .

FIG. 18 is a diagram showing a relationship between an imaging target and a light receiving range in the third embodiment.

FIG. 19 is a diagram showing an output level of an image signal in the third embodiment.

FIG. 20 is a diagram showing a relationship between a shooting range and a light receiving range in a vehicle traveling state according to a third embodiment.

FIG. 21 is a diagram showing an output level of an image signal in a vehicle traveling state of the third embodiment.

FIG. 22 is a diagram showing an image charge accumulation state in the third embodiment.

FIG. 23 is a block diagram showing a configuration of a fourth example.

FIG. 24 is a diagram showing a shooting range in a fourth embodiment.

FIG. 25 is a diagram showing a relationship between a subject to be photographed and a light receiving unit in the fourth embodiment.

FIG. 26 is an explanatory view of the principle of a passive triangulation type rangefinder.

FIG. 27 is an explanatory view of the principle of a passive triangulation type rangefinder.

FIG. 28 is a diagram showing a shooting range when the light receiving unit is arranged in the horizontal direction.

FIG. 29 is a diagram showing a relationship between an imaging target and a light receiving range when the light receiving unit is arranged in the horizontal direction.

FIG. 30 is a diagram showing a shooting range when a light receiving unit is arranged in a vertical direction.

FIG. 31 is a diagram showing a relationship between an object to be photographed and a light receiving range when the light receiving unit is arranged in the vertical direction.

[Explanation of symbols]

100 vehicle 101 1st lens 102, 401 1st pixel group 102 ', 652, 656 light receiving range 103, 108 pixels 104, 405 1st signal output part 106 2nd lens 107, 402 2nd pixel group 109, 406 Second signal output unit 110, 304, 409 Distance calculation unit 111, 202 Judgment warning unit 115, 203, 305, 411, 651, 655 Imaging range 201, 303 Contrast calculation unit 301, 403 First carry-over accumulation unit 302, 404 2nd carry-over accumulation part 407 1st average processing part 408 2nd average processing part 415 division part 610 white line 611 guardrail

Claims (4)

[Claims] 1. A first pixel group in which a plurality of pixels are arranged on a straight line or a plurality of parallel straight line groups including the straight line, and a first pixel mounted on a vehicle in a rearward direction. A first image pickup unit focusing on the group, a first signal output unit for reading out a first image signal in time series according to the incident light intensity in each pixel of the first pixel group, and a plurality of pixels A second pixel group formed by being arranged on the same straight line as the first pixel group or on the straight line group; and a second pixel group mounted on the vehicle in the rearward direction and focused on the second pixel group. And a second signal output section for reading out a second image signal according to the intensity of incident light in each pixel of the second pixel group in time series, and the first signal output. Image signal output from the first signal output unit and connected to the first signal output unit and the second signal output unit. Signal and the second image signal output from the second signal output unit, and a distance calculation unit that calculates a distance to another vehicle approaching from the rear side, and a distance calculation unit that calculates the distance. And a determination alarm unit for generating an alarm by determining that another vehicle is approaching too much on the basis of the distance information, wherein the first pixel group and the second pixel group are substantially parallel to the road surface trajectory. A rear side vehicle notification device characterized by being arranged. 2. The determination warning unit is connected to a contrast calculation unit for calculating the contrast of the image signal, and does not issue an alarm when the contrast of the image signal calculated by the contrast calculation unit is smaller than a predetermined value. The rear side vehicle alarm device according to claim 1. 3. The first pixel group and the second pixel group leave image charges accumulated in the first pixel group and the second pixel group, respectively, and additionally accumulate new image charges. A first carry-over accumulation unit and a second carry-over accumulation unit, and a contrast calculation unit for calculating the contrast of an image signal is connected to the second carry-over accumulation unit. 2. The rear side vehicle notification device according to claim 1, wherein the carry-over accumulation unit adjusts the time and the number of carry-over accumulations of the image charges according to the contrast of the image signal calculated by the contrast calculation unit. 4. The first pixel group and the second pixel group are each formed by arranging a plurality of pixels two-dimensionally, and the first signal output section and the second signal output section are formed. A first averaging unit and a second averaging unit are respectively provided in the subsequent stages, and the first averaging unit and the second averaging unit enable the first pixel group and the second pixel. The image signal of the photographic screen imaged in the group is divided into a plurality of divisions including a predetermined number of pixels in the direction parallel to the road surface trajectory, and the pixel signals in the divisions are averaged to obtain another vehicle. 4. The rear side vehicle alarm system according to claim 3, wherein the distance is measured.