JPH09142210A - Monitor device for vehicular peripheral circumference - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a monitor device which is so formed up that it can image pick-up the inside of an area with optimum brightness even when there exists locally areas hardly recognized visually in the inside of an image pick-up area. SOLUTION: The device is so constituted as to be provided with an image pick-up means 10 image-picking up the peripheral area of a vehicle, a brightness adjusting means 31a adjusting the luminous energy of an image injected in the means 10 based on the shade of black and white information of images in the peripheral area image-picked up by the means 10, and with a display means 41 indicating image information image-picked up by the means 10, and also as to inform a driver of an image in vehicular peripheral circumference based on image information from the means 10. In this case, the device is also provided with a light measuring means 31b forwarding the shade of black and white information of a light measuring objective area to the brightness adjusting means 31a where a range of a prescribed area in the image of the peripheral area is made the light measuring objective area, and with a light measuring area changing means 31c setting the light measuring objective area by the light measuring means 31b at a given area.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle periphery monitoring device, and more particularly, it is effectively applied to monitor the periphery of a vehicle such as an automobile to assist the driver's safety confirmation in driving the vehicle. The present invention relates to a vehicle surroundings monitoring device.

[0002]

2. Description of the Related Art Conventionally, a vehicle periphery monitoring device for monitoring the periphery of a vehicle such as an automobile has been proposed and put into practical use. This vehicle periphery monitoring device captures an image of the area (monitoring area), such as the rear or side of the vehicle, which is difficult to see from the driver (monitoring area) by using a video camera attached to the vehicle and the captured image. It is displayed by a display attached on the dashboard of, and monitors the monitoring area.

The video camera in this vehicle periphery monitoring device is generally provided with an auto iris mechanism as a brightness adjusting mechanism for picked-up images. This auto iris mechanism is a mechanism that adjusts the aperture amount of the diaphragm provided in the lens of the video camera or controls the shutter speed of the electronic shutter based on the brightness of the captured image. Even when the brightness of the subject changes at night, it is possible to display an image of the optimum brightness that is easily visible to the driver.

In this auto iris mechanism, the average brightness value (corresponding to the brightness of the image) of the entire screen in the captured image is calculated, and the aperture amount of the lens diaphragm or the shutter speed of the electronic shutter is calculated based on this average brightness value. Metering method, or the average brightness value of the central part of the screen in the captured image, and the metering method of adjusting the aperture of the lens diaphragm or the shutter speed of the electronic shutter based on the average brightness value of the central part of the screen. Have been adopted.

[0005]

In an apparatus having such an auto iris mechanism, as described above, the aperture amount of the lens diaphragm or the electronic shutter of the electronic shutter is determined based on the average brightness value of the entire screen or the central area of the screen. Since the shutter speed is adjusted, when a scene such as daytime where the difference in illuminance is extremely large is imaged, a region that is locally dark or bright enough to be invisible may appear.

More specifically, each pixel forming the picked-up image has 256 gradations, that is, a luminance value of "0" to "25".
5 "pixels, this auto iris mechanism causes the aperture of the lens aperture or the electronic shutter of the electronic shutter so that the average brightness of the captured image becomes, for example, about" 80 "to" 180 ". The shutter speed is adjusted.

In this case, the region locally illuminated by sunlight or another light source becomes a high-luminance region having a luminance value of "200" or more, and the region shaded by the object is The luminance value is a low luminance area of "40" or less, which is a region which is difficult for the driver to visually recognize. If an obstacle exists in such a region where it is difficult to visually recognize, it is difficult to confirm the obstacle.

In particular, when there is an area that is difficult to visually recognize at the immediately preceding position on the traveling direction side of the vehicle, it is difficult to confirm this obstacle, and at the same time, there is a high possibility that the vehicle collides with this obstacle. turn into. The same is true when there is a region that is difficult to visually recognize on the traveling path of the vehicle, and it is difficult to confirm the obstacle, and the vehicle is more likely to collide with the obstacle.

On the other hand, when the vehicle is traveling, the driver's viewpoint changes according to the traveling speed.
That is, the driver's viewpoint is in a region near the vehicle when the vehicle is stopped or at a low speed, and the viewpoint moves further as the traveling speed increases. In this case, if there is an area that is difficult to visually recognize in the area where the driver's viewpoint is present, it becomes difficult to check the obstacle in that area, and the possibility that the vehicle collides with the obstacle increases. .

The present invention has been made in view of these points, and is configured such that even if there is a locally difficult region to visually recognize in the image pickup region, it is possible to take an image in the region with optimum brightness. The main issue is to provide a vehicle surroundings monitoring device, and improve the visibility by the driver by capturing the image in the area corresponding to the driver's point of view so that there is no difficult area to see. Another object is to provide a vehicle surroundings monitoring device that can perform the above.

[0011]

In order to solve the above-mentioned problems, a vehicle periphery monitoring device according to the present invention has an image pickup means (10) for picking up an image of a peripheral region of a vehicle as shown in the basic configuration diagram of FIG. A brightness adjusting means (31a) for adjusting the light quantity of the image incident on the image pickup means (10) based on the brightness information of the peripheral area image picked up by the image pickup means (10), and the image pickup means ( A vehicle periphery configured to have a display means (41) for displaying image information captured by (10), and configured to allow a driver to visually recognize the image around the vehicle based on the image information from the image capturing means (10). In the monitoring device, a predetermined area range in the peripheral area image is set as a light measurement target area, and light / dark information of the light measurement target area is sent to the brightness adjusting means (31a) (31b).
And a photometric area changing means (31c) for setting the photometric target area by the photometric means (31b) to an arbitrary area. (Claim 1)

The photometric area changing means (31c)
Is characterized in that the light measurement target region is set to a region immediately before the traveling direction of the vehicle. (Claim 2)

Further, the photometric area changing means (31c)
Is characterized in that the photometric target area is set on the predicted route of the vehicle based on the predicted route information from the route prediction means (31d) that predicts the route of the vehicle based on the turning information of the vehicle. (Claim 3)

The path predicting means (31d) includes a steering wheel steering angle sensor (61a) for detecting a steering wheel steering angle,
Steering angle detection sensor (61b) for detecting the steering angle of the steered wheels
Is predicted based on the turning information of the vehicle output from at least one of the above. (Claim 4)

Further, the photometric area changing means (31c)
Is a speed information output means (6) for outputting the traveling speed of the vehicle.
According to the speed information from 2), as the running speed of the vehicle increases, the photometric target area is set to a far area from the vehicle. (Claim 5)

Further, the photometric area changing means (31c)
Sets the photometric target area on the predicted route of the vehicle based on the predicted route information from the route prediction means (31d) that predicts the route of the vehicle based on the turning information of the vehicle, and outputs the traveling speed of the vehicle. According to the speed information from the speed information output means (62), the higher the vehicle travels, the more the metering target area is set to the far area on the predicted course. (Claim 6)

Further, the image pickup means (10) is provided on the rear side of the vehicle so as to obtain a picked-up image of an area behind the vehicle and extending from the near-vehicle area to the far-back area. The area changing means (31c) is configured to be in an active state only when the backward movement information is sent from the backward movement detecting means (63) for detecting the backward movement of the vehicle based on the gear position of the vehicle, and the vehicle starts to move backward. In this case, the light measurement target area is set to the area immediately before the vehicle traveling direction. (Claim 7)

Further, it is characterized in that operation switching means (64) operated by a driver or the like to selectively operate the photometric area changing means (31c) is provided. (Claim 8)

Further, it is characterized in that a brightness changing means (65) for adjusting the brightness of the picked-up image is provided in the operating state of the photometric area changing means (31c). (Claim 9)

In the structure of claim 1, the photometric means (31b) sets the arbitrary area set by the photometric area changing means (31c) as the photometric target area, and the light and dark information of the photometric target area is adjusted by the brightness adjusting means ( 31a). The brightness adjusting means (31a) adjusts the incident amount of the image incident on the imaging means (10) based on the light / dark information from the photometric means (31b).

That is, according to the first aspect of the present invention, the means for setting the photometric target area in the image pickup area to a desired arbitrary area and the image pickup means so that the set photometric target area has the optimum brightness. Since a means for adjusting the amount of incident light is provided, even if there is an image with a large difference in light and shade such as the area exposed to direct sunlight and the shadow area in the captured image, the image in the area to be measured is good. Can be recognized.

Then, the photometric target area of the photometric area changing means (31c) shown in claim 1 is set as an area immediately before the traveling direction of the vehicle as described in claim 2.

As described above, by setting the light measurement target area to the area immediately before the traveling direction of the vehicle, the area that requires the most attention is the light measurement target area immediately before starting the vehicle or when moving at a slow speed. Can increase the safety in.

Further, as described in claim 3, the photometric target area of the photometric area changing means (31c) shown in claim 1 predicts the course of the vehicle based on the turning information of the vehicle. According to the predicted course information from the means (31d),
It is set as an area on the predicted route of the vehicle.

As described above, the route of the vehicle is predicted based on the turning information of the vehicle, and the region for photometry is set on the predicted route of the vehicle. Is the target area for photometry,
The safety during driving can be improved.

Then, as a concrete configuration of the course predicting means (31d) described in claim 3, the configuration described in claim 4 is applied. And each structure of the said claim performs the following effects. That is, the steering wheel steering angle sensor (61a) detects the steering wheel steering angle given as the operation amount of the steering wheel that determines the turning radius of the vehicle. The steering angle detection sensor (61b) detects the steering angle of the steered wheels.
Then, the route prediction means (31d) is provided with the steering wheel steering angle sensor (61a) and the steering angle detection sensor (61b).
The route of the vehicle is predicted based on the output from at least one of the sensors.

Thus, based on the output from the means for indirectly detecting the turning radius of the vehicle [steering angle sensor (61a)] or directly [steering angle detection sensor (61b)], that is, the turning information of the vehicle. Since it is configured to predict the course of the vehicle, it is possible to reliably predict the course of the vehicle.

Further, the photometric target area of the photometric area changing means (31c) described in claim 1 is, as shown in claim 5, a speed information output means (62) for outputting the traveling speed of the vehicle. Is changed according to the speed information of the vehicle, and the farther the vehicle travels, the farther the vehicle is set.

As described above, the means for detecting the traveling speed of the vehicle is provided, and as the traveling speed of the vehicle increases, the area to be measured is set to the farther area from the vehicle based on the traveling speed information of the vehicle. Therefore, by changing the area to be intensively monitored according to the speed of the vehicle, the area to be intensively monitored can be always made to have a brightness that is easy to see, and the safety during driving can be improved. .

Further, as shown in claim 6, the photometric target area of the photometric area changing means (31c) shown in the above claim 1 outputs predicted path information and speed information from the path predicting means (31d). Depending on the speed information from the means (62),
The higher the vehicle travels, the farther the region is set on the predicted course.

As described above, based on the turning information and the traveling speed information of the vehicle, as the traveling speed of the vehicle increases, the photometric target area is set in the far area on the predicted course of the vehicle. By changing the area to be intensively monitored according to the speed of the vehicle, the area to be intensively monitored can be always made to have a brightness that is easy to see, and safety during driving can be improved.

According to the seventh aspect of the present invention, the image pickup means (10) is provided on the rear side of the vehicle to pick up the image of the rear side of the vehicle, and the backward movement detecting means detects the backward movement of the vehicle based on the gear position of the vehicle. A means (63) is provided, and when the backward movement information is sent from the backward movement detecting means (63), the photometric area changing means (31c) is set in the active state, and when the vehicle is going to move backward, Since it is configured to be set in the area immediately before the traveling direction, the area behind the vehicle, which is difficult for the driver to visually recognize, can be made to have a brightness that is easy to see, and safety during driving can be improved.

Further, in the structure of claim 8, since the operation switching means (64) for selectively operating the photometric area changing means (31c) is provided, the photometric area can be switched at any timing by the switching operation by the driver or the like. Can be changed.

Further, in the structure of claim 9, since the brightness changing means (65) for adjusting the brightness of the picked-up image is provided in the working state of the photometric area changing means (31c) described above, When there is an invisible region in the captured image captured in this state, the light / dark state can be adjusted according to this region, and the usability can be improved.

[0035]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 2 is a block diagram illustrating a configuration of an apparatus to which the present invention is applied. In FIG. 2, reference numeral 10 is an image capturing unit as an image capturing unit that captures an image around the vehicle, and 20 is captured image information obtained from the image capturing unit 10. Alternatively, a storage unit that holds the shape information of the vehicle, 30 is a data processing unit configured by a computer that operates according to a prestored program, 40 is a display unit including a display 41, and 50 is an alarm sound or voice guidance. An alarm unit 60 for detecting the steering angle of the steering wheel or the steering angle of the steered wheels, or collecting various switch information, and inputting a signal for sending the steering angle information or the switch information to the data processing unit 30. It is a department.

The image pickup section 10 is composed of a CCD camera 11 having a lens 11a and an image plane 11b. The image pickup section 10 is, for example, as shown in FIG.
The vehicle 100 is mounted at a substantially central portion on the upper rear side at a ground contact height H and a depression angle θ _A with respect to a normal line of the ground. As a result, the image capturing unit 10 is provided in the monitoring area 1 behind the vehicle 100.
Obstacles and the like in 00a are detected.

Further, the image pickup unit 10 has an iris for adjusting the aperture amount of a diaphragm provided in the lens according to an iris adjustment signal IS from the data processing unit 30 or for increasing / decreasing the shutter speed of an electronic shutter. An adjusting mechanism 12 is provided. The mounting position of the image pickup unit 10 is stored in a vehicle data memory 22 (described later) of the storage unit 20 as reference position data when defining the position of the vehicle.

The storage unit 20 temporarily stores the information of the picked-up image from the image pickup unit 10, the current position data of the vehicle, the two-dimensional or three-dimensional shape data of the vehicle, and the image pickup unit 10 in the vehicle. The vehicle data memory 22 holds the vehicle reference position data that is the mounting position of the vehicle 100, the wheel base data that is the arrangement interval of the front and rear wheels of the vehicle 100, the vehicle width data of the vehicle 100, and the like as vehicle information. In addition, the frame memory 21 includes a matrix of pixel groups corresponding to image pickup pixels, for example, 512 ×
It is configured as a 512-pixel memory, and each pixel has 256
Luminance information of gradation (value “0” to value “255”) is given.

The data processing unit 30 has a CPU 31 which operates according to an operation program, a ROM 32 which stores this operation program, and a RAM 33 which temporarily stores information required when the CPU 31 operates. The CPU 31 has the storage unit 20 and the display unit 4 described above.
0, the alarm unit 50, the signal input unit 60, and various control information are transmitted / received, and as described above, the iris adjustment signal IS is output to the iris adjustment mechanism 12 of the imaging unit 10.

The display unit 40 is a display 41 as a display unit, and image information displayed on the display 41 is captured image information from the image capturing unit 10 described above, image information generated by the data processing unit 30, or both images. It has a selector 42 for selecting whether to use a composite image of information,
Based on the display image signal output from the CPU 31, the relative position of the object with respect to the vehicle is displayed, or a message to the driver is displayed.

The alarm unit 50 includes a speaker 51 and a CPU 3
And a drive circuit 52 that generates a buzzer signal or an audio signal based on the control signal from the controller 1 and outputs the audio signal to the speaker 51.

The signal input section 60 has a steering angle detection section 61, a traveling sensor 62, a back gear detection sensor 63, a photometric area instruction switch 64, and a brightness variable instruction switch 65. The steering angle detection unit 61 includes a steering wheel steering angle sensor 61a that indirectly detects the turning information of the vehicle by detecting the steering angle of the steering wheel, and a steering that directly detects the turning information of the vehicle by detecting the steering angle of the steered wheels. An angle detection sensor 61b is provided, and outputs from the steering wheel steering angle sensor 61a and the steering angle detection sensor 61b are output as vehicle turning information.

The running sensor 62 includes, for example, a magnet mounted on the transmission shaft, a Hall element disposed adjacent to the magnet, and a comparison voltage variable according to an output from the Hall element at one terminal thereof. It is equipped with a comparator (not shown) that is supplied to (for example, + terminal) and a reference voltage is supplied to the other terminal (for example, − terminal), and the traveling pulse is output from the comparator when the transmission shaft rotates. It is configured as a mechanism to do.

The back gear detection sensor 63 is provided, for example, in a transmission mechanism (not shown), detects that the gear position of this transmission mechanism is a back gear used when the vehicle moves backward, and outputs a detection signal. It is configured as a mechanism to do.

The photometric area instruction switch 64 is configured as a switch mechanism that is operated when changing the photometric area, and the photometric area instruction switch 64 causes the photometric area to be located in the immediately preceding area behind the vehicle, and the captured image ( Rear image)
The entire area, the upper area in the captured image, or the automatic setting is performed.

The variable brightness instruction switch 65 is configured as a mechanism for changing the brightness of a captured image taken in a state where the function of changing the light measurement target area is operating. Thus, when there is an invisible area in the captured image, the bright / dark state can be adjusted according to this area.

A specific example (first section) having the above-mentioned structure will be described below.
(Specific example of) will be described with reference to a flowchart. In the first specific example, first, in step S110 in the flowchart of FIG. 4, the image capturing operation by the imaging unit 10 is performed. The acquired image in step S110 is an image whose incident light amount is adjusted by the CPU 31 of the data processing unit 30, that is, an image whose brightness is adjusted by the iris adjusting mechanism 12 described above.

For example, as shown in FIG. 7 (a), when the sunlight DL is radiated obliquely above and in front of the vehicle 100, the sunlight SH causes a shadow SH extending to the rear of the vehicle 100. Occur. Then, as shown in FIG.
When the image pickup unit 10 is attached so as to pick up an image of the rear upper substantially central portion of the vehicle 100 and a region immediately before the rear of the vehicle 100 to a horizontal region, the image pickup unit 10 is used as shown in FIG. In addition, a captured image in which a part of the rear end portion of the vehicle 100 (for example, a bumper) and the above-described shadow SH are located from the lower part of the screen to the center and the horizontal line HL is located on the upper part of the screen is acquired.

In the picked-up image shown in FIG. 8, the shutter speed of the electronic shutter is adjusted by the iris adjusting mechanism 12 described above, for example, based on the average luminance value of the entire screen area, and is incident on the image pickup section 10. Since the amount of light is limited, the shadow SH becomes a darkly projected area. Then, this shadow SH becomes a locally invisible area, and when an obstacle exists in this area, it is difficult to confirm this obstacle.

In the subsequent step S120, a measurement target area acquisition process is performed. This measurement target area acquisition process is specifically performed by the flowchart of FIG. Less than,
This will be described with reference to the flowchart of FIG. In this measurement target area acquisition process, first, step S210.
Then, it is determined whether or not the photometry area instruction switch 64 of the signal input unit 60 is operated, and more specifically, whether or not the photometry area is the area immediately before the rear of the vehicle or the area set automatically. Then, if the immediately preceding rear area is designated as the photometric area by the photometric area instruction switch 64, the process proceeds to step S230, while if the designation by the photometric area instruction switch 64 is automatic setting, step S220.
Move to

In step S220, it is determined whether the gear position of the speed change mechanism is the back gear. Then, the determination of the gear position is made based on the detection signal from the back gear detection sensor 63 of the signal input unit 60, and when the detection signal indicating the back gear is output, it is determined to be "Y" and the process proceeds to step S230. Transition. on the other hand,
If no detection signal is output in this gear position determination, that is, if the gear position of the speed change mechanism is other than the back gear, it is determined to be "N" and the subsequent processing is not performed. The process moves to step S110, and the processing operation in the next operation cycle is executed (RTS).

In step S230, a process for setting the photometric target area to an arbitrary area in the image pickup area is performed. More specifically, in the first specific example, the photometric target area is shown in FIG.
Is set in an area immediately before the rear which is the traveling direction of the vehicle indicated by reference numeral 200 (A). In the actual process,
In this step S230, the immediately preceding area 200 (A)
The coordinate value on the frame memory 21 of the line indicating the boundary of is given. As described above, the reason why the area to be metered is the area 200 (A) immediately before the rear of the vehicle is the area immediately before the rear 20.
This is because 0 (A) is a blind spot from the driver, and if there is an obstacle in this area, the possibility of collision between the vehicle and the obstacle increases.

By setting the light measurement target area to the rear right area 200 (A), the area requiring the most attention at the time immediately before starting the vehicle or at the time of slow speed reversal is the light measurement target area, that is, the iris. It serves as a reference area for brightness information in the brightness adjustment operation by the adjusting mechanism 12, and as will be described later, this area 200 immediately before the rear side.
(A) is set to the brightness that is most visible to the driver. Then, when the process of step S230 ends, the process proceeds to step S130 in the flowchart of FIG.

In step S130, the light and dark information acquisition processing in the measurement target area is performed. The light / dark information acquisition process in the measurement target region is specifically performed by the flowchart of FIG. Hereinafter, description will be made with reference to the flowchart of FIG. In the bright / dark information acquisition process in the measurement target region, first, in step S310, the coordinate value of the pixel to be processed is acquired. In the following step S320, it is determined based on the coordinate value of the processing target pixel acquired in the above step S310 whether or not this processing target pixel is a pixel within the photometric target area set in the above step S230.

If it is determined in the determination processing of step S320 that the pixel to be processed is a pixel within the photometric target area (Y), the brightness value of the pixel to be processed is acquired in subsequent step S330. And this step S
The luminance value of the pixel to be processed acquired in 320 is held in the RAM 33 of the data processing unit 30, and step S3
Move to 40. On the other hand, in the determination processing of step S320, when the processing target pixel is determined to be a pixel outside the photometric target area (N), the processing of step S330 is skipped and the process proceeds to step S340.

In step S340, it is determined whether or not the determination processing in steps S310 to S330 has been completed for all pixels in the image pickup area, that is, in the frame memory 21. Then, in the determination processing of step S340, when it is determined that the determination processing has been completed for all pixels, the process proceeds to subsequent step S350.
If there is an undetermined pixel, the process moves to step S310 described above again, and a series of processing is executed for this undetermined pixel.

In step S350, the average luminance value of the pixel group in the measurement target area is calculated. More specifically, in the process of calculating the average brightness value in step S350, the brightness values of the processing target pixel group held in the RAM 33 in step S330 are read out and integrated, and the integrated value of the pixel group is further calculated. Execute the process of dividing by the number. The average luminance value of the pixel group calculated in this way, that is, the brightness information in the measurement target area is also RA
Store and hold in M33. And this step S35
When the process of 0 ends, the light and dark information acquisition process in the measurement target region ends.

The operation of the above-described series of brightness information acquisition processing in the measurement target area will be described with reference to FIG. FIG. 9 is a schematic diagram illustrating the configuration of the frame memory 21. As shown in the figure, the frame memory 21 has a configuration in which pixels are arranged in a matrix on the XY coordinates. In the frame memory 21, the coordinate values (4, 0) to (6, 0), the coordinate value (4,
1) to (6,1) and coordinate values (4,2) to (6,6)
The following description will be made assuming that the pixel group in the area G shown in 2) is a pixel group in the measurement target area.

In the brightness information acquisition process, first, the coordinate value (0,0) of the origin as the reference point is acquired (S310), and the pixel a1 is measured based on this coordinate value (0,0). It is determined whether the pixel is in the target area (S320). This pixel a1 [coordinate value (0,0)]
Is determined to be a pixel outside the measurement target region, and the coordinate value (0, 1) of the pixel a2 that is the next determination target pixel is acquired (S
310). This pixel a2 [coordinate value (0, 1)] is also determined to be a pixel outside the measurement target area (S320), similarly to the previous pixel a1, and the process proceeds to the determination for the next coordinate value.

Thereafter, such processing is sequentially executed.
In the process, the pixel group of the area G is determined to be a pixel in the measurement target area (S320), the brightness value thereof is acquired, and the acquired brightness value is stored and held in the RAM 33 (S330). Then, coordinate values (511, 51
When the determination processing and the luminance acquisition processing described above are performed up to the pixel of 2), it is determined that the processing for all the pixels in the frame memory 21 is completed (S340), and the pixel group in the measurement target area, that is, the pixels in the area G is determined. An average brightness value for the group is calculated.

More specifically, the coordinate values (4,0) to (6,0), the coordinate values (4,1) to (6,1), and the coordinate values (4,2) to (, which constitute the region G are described. 6, 2) luminance value integration processing of each pixel and division processing of the integration value by the number of pixels (value “9”) are performed, and the division value is stored in the RAM 33 as light and dark information indicating the brightness in the measurement target area. It is stored (S350).

In the light / dark information acquisition processing in the measurement target area described above, the average luminance value in the measurement target area is used as the light / dark information, but in the light / dark information acquisition processing, the average brightness value in the measurement target area is measured. It is also possible to obtain a distribution of brightness values and use the brightness value having the highest frequency (the number of existing) as the brightness information.

When the light / dark information acquisition process in the measurement target region in step S120 (steps S310 to S350) described above is completed, the process proceeds to step S140 in the flowchart of FIG. In this step S140, the threshold value for determining the lightness and darkness in this measurement target region is determined.

This threshold value determination process is a process performed based on the instruction information from the brightness variable instruction switch 65 described above. More specifically, the instruction information from the brightness variable instruction switch 65 is " When the instruction is to change from “dark” to “bright”, the threshold value I _thr is set to, for example, the value “2”.
00 ”and the instruction information is a“ normal ”instruction, the threshold I _thr is set to, for example, a value“ 128 ”, and the instruction information is an instruction to change from“ bright ”to“ dark ”. For example, the threshold I _thr is set to a value “100”, for example.
Then, the determined threshold value is stored in the RAM 33,
Then, the process proceeds to step S150.

In step S150, the above step S1
The average luminance value information in the measurement target area, that is, the brightness information acquired in step 30 is compared with the threshold value determined in step S140. More specifically, this step S15
In the comparison processing of 0, when the light / dark information is I _ave ,
The magnitude comparison between the brightness information I _ave and the threshold value I _thr is performed.

Then, in the following step S160,
Based on the comparison process in step S150, a shutter speed setting process for an electronic shutter (not shown) of the CCD camera 11, that is, a light (image) for the imaging unit 10 is performed.
The adjustment operation of the incident amount of is performed. That is, this step S
In 160, if the light / dark information I _ave is smaller than the threshold value I _thr in accordance with the magnitude relation between the light / dark information I _ave and the threshold value I _thr , the shutter speed of the electronic shutter of the CD camera 11 is reduced. By doing so, the exposure time is lengthened and the amount of incidence on the imaging unit 10 is increased.

Then, the brightness information I _ave and the threshold value I _thr
If and substantially match, the shutter speed of the electronic shutter is maintained as it is and the incident amount on the imaging unit 10 is not changed. Further, the brightness information I _ave is the threshold value I _thr.
If it is larger than the above, the exposure speed is shortened by increasing the shutter speed of the electronic shutter of the CCD camera 11, and the incident amount to the image pickup unit 10 is reduced.
Then, when the shutter speed setting process for the electronic shutter in step S160 ends, the process moves to step S110 again (RTS), imaging is performed at the set shutter speed, and an image in the next operation cycle is acquired.

In the first specific example described above, the area to be measured is the area immediately before the rear which is the traveling direction of the vehicle. Therefore, the most attention should be paid when the vehicle is about to start or when the vehicle is moving backward at a slight speed. The required area becomes the metering target area, and the safety during operation can be improved.

Next, another specific example (second specific example) in which the set measurement target area is set based on the route of the vehicle will be described below. The difference between the second specific example and the first specific example is that the data processing unit 30 (C
The processing executed by the PU 31), particularly the measurement target area setting processing (step S12 in the flowchart of FIG. 4).
0) and other processing is the same as in the first specific example. Therefore, in this second specific example, the processing of this difference will be described, and regarding other processing, an outline of the processing will be described as necessary.

Then, in the second specific example, first, the image pickup operation of the image pickup section 10 is performed (step S110 in the flowchart of FIG. 4) to obtain a picked-up image in a state where the iris adjusting mechanism 12 is functioning.
Then, the measurement target area setting process is performed on the acquired captured image (at step S120). This measurement target area setting process is specifically performed by the flowchart of FIG. Hereinafter, description will be given with reference to the flowchart of FIG.

In this measurement target area acquisition process, first, in step S410, it is determined whether or not the light measurement area instruction switch 64 of the signal input unit 60 is operated, and more specifically, whether the designation of the photometry target area is automatic setting. judge. Then, in this determination process, the photometric area instruction switch 64
If the designation by is automatic setting, step S42
On the other hand, if this designation is another designation, the process proceeds to step S110 of FIG. 4 without performing the subsequent process, and the process operation in the next operation cycle is executed (RT
S).

In step S420, it is determined whether the gear position of the speed change mechanism is the back gear. Then, the determination of the gear position is made based on the detection signal from the back gear detection sensor 63 of the signal input unit 60, and when the detection signal indicating the back gear is output, it is determined to be "Y" and the process proceeds to step S430. Transition. on the other hand,
If it is determined in this gear position that the gear position is other than the back gear, it is determined to be "N", and the process proceeds to step S110 in FIG.
The processing operation in the next operation cycle is executed (RTS).

In step S430, vehicle turning information is acquired, that is, vehicle turning information is obtained based on the output from at least one of the steering wheel steering angle sensor 61a and the steering angle detecting sensor 61b of the steering angle detecting section 61. Then, regarding the acquired turn information, the data processing unit 3
It is stored and held in the RAM 33 of 0.

In subsequent step S440, the course of the vehicle is predicted. Regarding the course prediction processing of this vehicle, FIG.
This will be described with reference to FIG. This figure is a schematic diagram showing the relationship between the steering angle of the vehicle 100 and the course of the vehicle.

In the figure, T _FR , T _FL , T _RR and T _RL
Is the wheel provided on the vehicle, θ _R is the steering angle of the right front wheel, θ _L
Is the steering angle of the left front wheel, L is the wheel base given as the arrangement interval of the front and rear wheels, and W is the width of the vehicle body (vehicle width). In the example of the figure, the steering angle θ _W of the wheels is, as shown in the following equation (1), the steering angle θ _{R of the} right front wheel and the steering angle θ of the left front wheel.
Given as the average angle of _L. θ _W = (θ _R + θ _L ) / 2 (1)

As shown in the figure, the virtual front wheel T _F given by the above equation (1) is set at the intermediate position in the width direction between the right front wheel T _FR and the left front wheel T _FL , and the virtual front wheel T
_If a perpendicular line LF with respect to the steering angle θ _{W of F and} a straight line RF connecting the centers of the right rear wheel T _FR and the left rear wheel T _FL are set, and further, the intersection point of these perpendicular lines LF and the straight line RF is set as the origin P ₀ , The origin P ₀ and the intermediate position P between the right rear wheel T _FR and the left rear wheel T _FL
distance X _C between _c can be expressed by the following equation (2). X _C = L / tan θ _W (2)

Based on this equation (2), the distance X _R between the origin P ₀ and the rear right end P _R, which is the position of the widthwise end of the vehicle intersecting the straight line RF, that is, the rear end of the vehicle 100. and the origin P ₀ and the distance X _L between the left rear end P _L can be expressed by the following equation (3) and (4). _{X R = L / tanθ W -W} / 2 ··· (3) X L = L / tanθ W + W / 2 ··· (4) From the above equation (3) and (4), the steering angle of the wheels θ _{When W} is given, the right rear end P _R of the vehicle 100 moves along an arc of radius X _R with reference to the origin P ₀ , as indicated by the reference symbol B _R in the figure, while The left rear end P _L moves along an arc having a radius X _L with reference to the origin P ₀ , as indicated by reference character B _L in the figure.

In step S440, the above-described processing is executed to calculate the movement loci B _R and _BL of the vehicle 100 from the wheel steering angle θ _W, and the movement loci B _R and _BL are predicted. It is held in the RAM 33 as a route.

Then, in the following step S450,
The predicted track area on the captured image is calculated based on the predicted track information acquired in step S440. In explaining the calculation process of the predicted course region, first,
The coordinate values in the coordinate space (XYZ) of FIG.
Coordinate space (X "Y" based on position 1)
Z ″) coordinate values are converted. This process will be described below.

In this case, first, as shown in FIG. 12, consider an X'Y'Z 'coordinate space whose origin is an intersection point of a perpendicular line extending downward from the grounding position of the image pickup section 10 (CCD camera 11) and the ground. When the coordinate conversion from the XYZ coordinate space of FIG. 11 described above to the X′Y′Z ′ coordinate space is performed, the coordinate values in both coordinate spaces may be moved in parallel. Therefore, the point S (X _S , Y _S , 0) on the vehicle path (movement locus B _L ) in the XYZ coordinate space of FIG.
2 in the X'Y'Z 'coordinate space S (X _S ′, Y _S
', 0).

Further, as shown in FIG. 13, this X'Y
Converting the'Z 'coordinate space to the X ", Y", Z "coordinate space based on the CCD camera installation position, this X",
The coordinate value (X _S ″, Y) of the point S in the Y ″, Z ″ coordinate space
_S ", Z _S " ) Can be expressed by the following equations (5) to (7). X _S " = X _S '... (5) Y _S " = Y _S 'cos ψ (6) Z _S ″ = Z _S 'sin ψ -H (7)

Next, with respect to the point S on the movement locus in the X ", Y", Z "coordinate spaces, the image forming point on the image plane 11b, that is, the coordinate position on the picked-up image will be described. CCD camera 11
FIG. 14A is a diagram showing the optical arrangement of the point S and FIG.
Is a perspective view of this optical arrangement, and FIG. 14B is an X ″, Y ″ plan view of this optical arrangement.

In these figures, f is the CCD camera 1
1 and the image plane 11b, that is, the lens 1
1a focal length, S (X _S " , Y _S " , Z _S ” ) Is one point on the movement trajectory in the X ″, Y ″, Z ″ coordinate space as described above, and I _S (v _S , u _S ) is the image plane 11
It is an image formation point corresponding to the point S on b. In addition,
As can be seen from the figure, the image plane 11b is
It is composed of a vu coordinate system corresponding to X "Z" coordinates.

In this case, as can be seen from FIG. 14 (b),
The v coordinate value v _S of the image forming point I _{S on} the image plane 11a based on the similarity of the triangle can be expressed by the following equation (8). _{v S = -f × (X S} " / Y _S ″) (8) Similarly, by assuming Z ″, Y ″ planes instead of the X ″, Y ″ planes of FIG. 14B, the image of the image forming point I _S is obtained. The u coordinate value u _S on the plane 11a is calculated by the following equation (9).
Can be represented by u _S = -f x (Z _S " / Y _s ″) (9)

[0085] The above-described coordinate value of the image point I _S (v _S,
u _S ) is represented as a point when the lens 11a of the CCD camera 11 has no distortion. However, the actual lens 11a has aberrations unique to the lens. Hereinafter, correction of this aberration will be described.

For example, considering a case where a lattice-shaped pattern is imaged, when the lens of the CCD camera 11 has no aberration, this lattice-shaped pattern is projected on the image plane 11b as shown in FIG. 15 (a). And is stored in the frame memory 31. Then, as shown in FIG. 15D, if the point s (v ₀ , u ₀ ) when there is no distortion is imaged at the point s ′ (v ₁ , u ₁ ) by the distortion, then The aberration amount D can be expressed by the following equation (10). _{D = [(v 0 -v 1} ) 2 + (u 0 -u 1) 2] 0.5 ··· (10)

Then, FIG. 15B or FIG.
In the distorted image as shown in (c), the aberration amount D increases in proportion to the cube of the distance from the optical axis. That is, since it is proportional to the cube of the distance from the center point of the lens to the point P, the right side of the above equation (10) can be expressed by the following equation (11). Defined by ^{_{[(v 0 -v 1) 2}} + (u 0 -u 1) 2] 0.5 = k [(v 0 2 -u 0 2) 0.5] 3 ··· (11) In the formula, k is a lens Proportional constant

Therefore, when the lens has distortion, the distortion can be corrected by, for example, performing the calculation of the following expression (12). v ₁ ≈v ₀ (1 + k (v ₀ ² + u ₀ ² )) u ₁ ≈u ₀ (1 + k (v ₀ ² + u ₀ ² )) (12)

From the above, the coordinate values v _S and u _S on the image plane 11a calculated by the above equations (8) and (9)
Is imaged at the coordinate value (v _S ′, u _S ′) shown by the following expression (13) due to the aberration of the lens 11a. v _S ′ ≈v _S (1 + k (v _S ² + u _S ² )) u _S ′ ≈u _S (1 + k (v _S ² + u _S ² )) (13) Then, in this step S450, the series of arithmetic processing described above is executed. Picked-up image (image plane 11
a) The predicted course area in the above is calculated, and an area obtained by slightly expanding the predicted course area in the width direction is set as the predicted course area.

By the measurement target area setting process described above, the predicted course indicated by reference numeral 100 (A) in FIG. 16 is obtained according to the turning information from the steering wheel steering angle sensor 61a or the steering angle detection sensor 61b of the steering angle detecting section 61. The area is calculated. Then, actually, the calculated predicted course region 10
A region 200 (B) obtained by slightly expanding 0 (A) in the width direction is set as the predicted course region.

By the way, this predicted course region 100 (A)
The reason for slightly expanding in the width direction is to include an obstacle having a height in the measurement target region. That is, the predicted course area 100 (A) described above is a height “0”, that is, an area on the road surface. In general, an obstacle has a height, and therefore, an obstacle having a height is out of the measurement target region within the range of the predicted course region 100 (A). In this way, the predicted course region is designated by reference numeral 100.
By expanding the range indicated by (A) to the range indicated by reference numeral 200 (B), an obstacle with a height can be included in this measurement target region.

Then, when the series of measurement target area setting processing described above is completed, the processing shifts to the processing of the flowchart of FIG. 4, and the series of processing described in the first specific example, that is, acquisition of light and dark information in the measurement target area. Processing (S130), threshold value determination processing (S140), comparison processing of the light / dark information in the measurement target region acquired in step S130 and the threshold value determined in step S140 (S150), electronic of CCD camera 11 The shutter speed setting process (S160) for the shutter is sequentially executed.

In the second specific example described above, the steering wheel steering angle sensor 61a for detecting the steering wheel steering angle given as the operation amount of the steering wheel for determining the turning radius of the vehicle and the steering angle detection for detecting the steering angle of the steered wheels. Sensor 61b)
The detection signal from is acquired as the turning information of the vehicle.
Further, since it is configured to predict the course of the vehicle based on this turning information and set the photometric target area on the predicted course of the vehicle, it is possible to reliably predict the course of the vehicle and drive the vehicle. The area required for this is the area subject to photometry, and the safety during operation can be improved.

Next, another specific example (third specific example) in which the set measurement target area is switched according to the traveling speed of the vehicle will be described below. The difference between the third specific example and the first specific example is also in the processing executed by the data processing unit 30 (CPU 31), particularly the measurement target area setting processing (S120), and the other processing is the first. This is done in the same manner as the specific example of. Therefore, also in the third specific example, this difference will be described, and regarding other processing, an outline of the processing will be described as necessary.

Then, in the third specific example, first, the image acquisition operation by the image pickup section 10 is performed (S11).
0), a captured image in a state where the iris adjusting mechanism 12 is functioning is acquired. Then, measurement target area setting processing is performed on the acquired captured image (S120). This measurement target area setting process is specifically performed by the flowchart of FIG. Hereinafter, description will be given with reference to the flowchart of FIG.

In this measurement target area acquisition process, first, in step S510, it is determined whether or not the light measurement area instruction switch 64 of the signal input unit 60 is operated, and more specifically, whether the measurement area is automatically set. judge. Then, in this determination process, the photometric area instruction switch 64
If the designation by is automatic setting, step S52
On the other hand, if this designation is another designation, the process proceeds to step S110 in FIG. 4 without performing the subsequent process, and the processing operation in the next operation cycle is executed (RT
S).

In step S520, it is determined whether the gear position of the speed change mechanism is the back gear. Then, the determination of the gear position is made based on the detection signal from the back gear detection sensor 63 of the signal input unit 60, and when the detection signal indicating the back gear is output, it is determined to be "Y" and the process proceeds to step S530. Transition. on the other hand,
If it is determined in this gear position that the gear position is other than the back gear, it is determined to be "N", and the process proceeds to step S110 in FIG.
The processing operation in the next operation cycle is executed (RTS).

In step S530, the vehicle traveling speed acquisition process, that is, the generation cycle of the traveling pulse output from the traveling sensor 62 is acquired, and the traveling speed information of the vehicle is acquired based on this generation cycle information. The RAM of the data processing unit 30 stores the acquired traveling speed information.
Store and hold in 33.

In subsequent step S540, a measurement target area determination process is performed based on the traveling speed information acquired in step S540. For example, this step S540
Then, when the vehicle is in a stopped state (traveling speed 0 km / h) or when the traveling speed is less than 5 km / h, it is determined to be a “low speed traveling state”, and the traveling speed is 5 km / h to 10 k
If it is less than m / h, it is judged as "medium speed running state",
When the traveling speed is 10 km / h or more, it is determined to be "high speed traveling state". Then, this determination result is stored in the RAM 33.
Is stored and held in step S550, and the process proceeds to step S550.

In step S550, setting processing of the measurement target area on the captured image is performed. The setting process of the measurement target region is performed based on the determination result of step S540, and when it is determined that the "low speed traveling state", the region immediately before the rear of the vehicle 100 indicated by reference numeral 200 (C1) in FIG. 18 is set. Set as the measurement target area. When it is determined that the vehicle is in the “high-speed traveling state”, the reference numeral 200 (C
When the distant region of the vehicle 100 shown in 3) is set as the measurement target region and the "medium speed running state" is determined, the rear immediately preceding region 200 indicated by reference numeral 200 (C2) in FIG.
An intermediate region 200 (C2) located between (C1) and the distant region 200 (C3) is set as a measurement target region.

When the series of measurement target area setting processing described above is completed, the processing shifts to the processing of the flowchart of FIG. 4, and the series of processing described in the first specific example, that is, acquisition of light and shade information in the measurement target area. Processing (S130), threshold value determination processing (S140), comparison processing of the light / dark information in the measurement target region acquired in step S130 and the threshold value determined in step S140 (S150), electronic of CCD camera 11 The shutter speed setting process (S160) for the shutter is sequentially executed.

In the third specific example described above, the farther the vehicle travels, the farther the vehicle travels in the measurement target area 200 (C) according to the speed information from the travel sensor 62 which outputs the traveling speed of the vehicle. Since it is configured to be set, by changing the area to be monitored intensively according to the speed of the vehicle, the area to be monitored intensively can be made to have a brightness that is always easy to see, and safety during driving Can be increased.

By the way, the second concrete example and the third concrete example described above can be combined with each other.
That is, first, by executing steps S410 to S450 in the flowchart of FIG. 10, the course of the vehicle is predicted based on the turning information of the vehicle, and the measurement target area is set (second specific example). Step S530 in the flowchart of FIG.
Through execution of step S550, as the vehicle travels at a higher speed, the measurement target area is set on the far side in the set predicted course area based on the traveling speed information of the vehicle (third specific example). Can be configured.

In this case, for example, as shown in FIG. 19, the predicted course region 200 (B) based on the turning information of the vehicle is set by the execution of steps S410 to S450, and the predicted course region 200 (B) is set by the execution of steps S530 to S550. Within the predicted course region 200 (B), the measurement target regions 200 (B1) to 200 (B3) are set based on the traveling speed information of the vehicle.

As described above, based on the turning information of the vehicle from the steering angle detecting section 61 and the traveling speed information from the traveling sensor 62, as the traveling speed of the vehicle increases, the predicted traveling course prediction area 200 of the vehicle ( Since the photometric target areas 200 (B1) to 200 (B3) are set in the distant area on the upper side of B), the area to be intensively monitored is changed according to the speed of the vehicle. The area to be focused on can be always made to have a brightness that is easy to see, and the safety during driving can be improved.

As is apparent from the above description, the basic configuration of the present invention and the flowchart of the specific example have the following correspondence. That is, the brightness adjusting means 31a in the basic configuration of the present invention corresponds to step S110 in the flowchart of FIG. 4, the photometric means 31b corresponds to step S130 in the flowchart, and the photometric area changing means 31c corresponds to step S in the flowchart.
It corresponds to 130. Further, the route prediction means 31d in the basic configuration of the present invention corresponds to steps S430 to S450 in the flowchart of FIG.

In the first to third specific examples described above, the picked-up image is developed in the frame memory 21, and the light / dark information in the photometric area is acquired based on the brightness of the developed image. However, the present invention is not limited to this. For example, the CCD camera 1
It is also possible to configure so that the light / dark information in the photometric target area is acquired inside the unit 1.

[0108]

As described above, according to the present invention,
The following effects are obtained. That is, the means for setting the photometric target area in the imaging area to a desired arbitrary area and the means for adjusting the amount of light incident on the imaging means so that the set photometric target area has the optimum brightness are provided. Even if the captured image includes an image with a large difference in brightness such as a region irradiated with direct sunlight and a shadow region, the image in the photometric target region can be recognized well.

Further, by setting the light measurement target area to the area immediately in front of the traveling direction of the vehicle, the area requiring the most attention is the light measurement target area immediately before starting the vehicle or when moving at a slow speed. You can improve your sex.

Further, since the route of the vehicle is predicted on the basis of the turning information of the vehicle and the photometric target region is set on the predicted route of the vehicle, the region required for traveling the vehicle is measured. It becomes the target area, and the safety during driving can be improved.

Further, since the vehicle course is predicted based on the output from the means for indirectly or directly detecting the turning radius of the vehicle, that is, the turning information of the vehicle,
It is possible to reliably predict the course of the vehicle.

Further, a means for detecting the traveling speed of the vehicle is provided, and the region for photometry is set to the farther region from the vehicle as the traveling speed of the vehicle increases based on the traveling speed information of the vehicle. By changing the area to be monitored intensively according to the speed of the vehicle, it is possible to make the area to be monitored intensively always easy to see,
The safety during driving can be improved.

Further, the image pickup means is provided on the rear side of the vehicle so as to pick up the image of the rear side of the vehicle, and the backward movement detecting means for detecting the backward movement of the vehicle based on the gear position of the vehicle is provided. When the vehicle moves backward, the metering area changing means is set to the active state when the vehicle is sent, and the metering target area is set to the area immediately before the traveling direction of the vehicle. It is possible to make the area bright enough to see the area behind, and enhance safety during driving.

Since the operation switching means for selectively operating the photometric area changing means is provided, the photometric area can be changed at an arbitrary timing by the switching operation by the driver or the like.

Further, since the brightness changing means for adjusting the brightness of the picked-up image is provided in the operating state of the photometric area changing means, there is a hard-to-see area in the picked-up image in this state. In this case, the light / dark state can be adjusted according to this area, and the usability can be improved.

[Brief description of the drawings]

FIG. 1 is a diagram showing a basic configuration of the present invention.

FIG. 2 is a block diagram illustrating a configuration of an apparatus to which the present invention is applied.

FIG. 3 is an explanatory diagram of a mounting mode of the imaging unit 10.

FIG. 4 is a main flowchart explaining the operation of a specific example.

FIG. 5 is a flowchart of a measurement target area setting process in the first specific example.

FIG. 6 is a flowchart of a light / dark information acquisition process in a measurement target region in a specific example.

FIG. 7 is a diagram illustrating a surrounding situation when capturing a rear image.

FIG. 8 is a diagram showing an example of a captured image (rear image), and is a diagram for explaining a state in which the measurement target region is set to the rear immediately preceding region.

9 is a schematic diagram illustrating the configuration of the frame memory 21. FIG.

FIG. 10 is a flowchart of a measurement target area setting process in a second specific example.

FIG. 11 is a schematic diagram showing the relationship between the steering angle of the vehicle 100 and the course of the vehicle.

FIG. 12 is a schematic diagram showing an X′Y′Z ′ coordinate space whose origin is an intersection point of a perpendicular line extending downward from the grounding position of the imaging unit 10 and the ground.

[FIG. 13] X ″ based on the CCD camera installation position,
It is a schematic diagram which shows a Y "and Z" coordinate space.

FIG. 14 is a schematic diagram showing an optical arrangement of the CCD camera 11 and the point S.

FIG. 15 is an explanatory diagram of lens aberration correction.

FIG. 16 is a diagram showing an example of a captured image (rear image),
It is a figure explaining the state which set the measurement object area | region to the vehicle track area.

FIG. 17 is a flowchart of a measurement target area setting process in a third specific example.

FIG. 18 is a diagram showing an example of a captured image (rear image),
It is a figure explaining the structure which sets variably the measurement object area | region according to the traveling speed of a vehicle.

FIG. 19 is a diagram showing an example of a captured image (rear image),
FIG. 5 is a diagram illustrating a configuration in which a measurement target region is variably set according to a traveling speed of a vehicle on a vehicle course region.

[Explanation of symbols]

 10 image pickup unit 11 CCD camera 20 storage unit 21 frame memory 22 vehicle data memory 30 data processing unit 31 CPU 32 ROM 33 RAM 40 display unit 50 alarm unit 60 signal input unit 61 steering angle detection unit 61a steering wheel steering angle sensor 61b steering angle detection Sensor 62 Travel sensor 63 Back gear detection sensor 64 Photometric area instruction switch 65 Brightness variable instruction switch 100 Vehicle IS iris adjustment signal

Claims (9)

[Claims] 1. An image pickup means for picking up an image of a peripheral area of a vehicle,
Brightness adjusting means for adjusting the amount of light of the image incident on the image pickup means based on the brightness information of the peripheral area image picked up by the image pickup means, and display means for displaying the image information picked up by the image pickup means. In a vehicle periphery monitoring device configured to allow a driver to visually recognize an image of the vehicle periphery based on image information from the image capturing unit, a predetermined region range in the peripheral region image is set as a photometric target region, A vehicle periphery monitoring device characterized in that it is provided with a photometric means for sending the brightness information of the photometric target area to the brightness adjusting means, and a photometric area changing means for setting the photometric target area by the photometric means to an arbitrary area. . 2. The vehicle periphery monitoring device according to claim 1, wherein the photometric area changing unit sets the photometric target area to an area immediately in front of a traveling direction of the vehicle. 3. The photometric area changing unit sets the photometric target area on the predicted course of the vehicle based on predicted course information from a course prediction section that predicts the course of the vehicle based on the turning information of the vehicle. The vehicle periphery monitoring device according to claim 1, which is characterized in that. 4. The route predicting means of the vehicle is based on turning information of the vehicle output from at least one of a steering angle sensor for detecting a steering angle of a steering wheel and a steering angle detecting sensor for detecting a steering angle of steered wheels. The vehicle periphery monitoring device according to claim 3, wherein the route is predicted. 5. The photometric region changing means sets the photometric target region to a farther region from the vehicle as the traveling speed of the vehicle increases in accordance with the speed information from the speed information output means for outputting the traveling speed of the vehicle. The vehicle periphery monitoring device according to claim 1, wherein: 6. The photometric area changing unit sets the photometric target area on the predicted course of the vehicle based on predicted course information from a course prediction section that predicts the course of the vehicle based on vehicle turning information, and 3. The region for photometry is set to a distant region on the predicted course as the vehicle travels at a higher speed, according to the speed information from the speed information output means for outputting the traveling speed of the vehicle. The vehicle periphery monitoring device described. 7. The image pickup means is provided at the rear of the vehicle so that a picked-up image of an area that is behind the vehicle and extends from a near-vehicle area to a far-back area of the vehicle is obtained, and the photometric area changing means. Is configured to be in an active state only when the reverse information from the reverse detecting means for detecting the reverse of the vehicle based on the gear position of the vehicle is transmitted, and when the vehicle is about to start moving backward, 7. The vehicle periphery monitoring device according to claim 1, wherein the vehicle periphery monitoring device is set in an area immediately before the traveling direction of the vehicle. 8. The operation switching means which is operated by a driver or the like to selectively operate the photometric area changing means is provided. Vehicle surroundings monitoring device. 9. The brightness changing means for adjusting the brightness of a picked-up image taken in the operating state of the photometric area changing means is provided.
The vehicle periphery monitoring device according to 5, 6, 7 or 8.