JP2009035162A - Rear view monitoring device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rear view monitoring device capable of monitoring a rear view while inhibiting dazzle generated by a light source in the rear view. <P>SOLUTION: This rear view monitoring device comprises a camera 10 for photographing a rear view, an image processing part 21 for processing an image photographed by the camera 10, a camera control part 22 for controlling the camera 10 and an image display part 31 for displaying the image processed by the image processing part 21. The image processing part 21 detects the brightness of points constituting the image, outputs the detected brightness information of points to the camera control part 22, performs an image processing for adjusting luminance in such a way that a driver can visually monitor the rear view with respect to a part showing predetermined brightness or higher set as one in which the driver feels dazzle and outputs the image processed. The camera control part 22 controls the camera 10 in such a way that the driver can visually monitor the rear view in reference to the brightness information of a part showing a value lower than a predetermined brightness value. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a rear visual recognition device capable of visually recognizing a rear visual field while preventing dazzling by a light source of the rear visual field.

  Rear mirrors such as inner mirrors mounted on vehicles etc. may be dazzled if the light of the headlight of the rear vehicle is directly reflected during night driving etc., by using an anti-glare mirror, The dazzling by the light of the headlight of the vehicle behind is suppressed. As the anti-glare mirror, for example, a prism-type anti-glare mirror using a prism mirror (for example, see Patent Document 1) and an automatic anti-glare mirror for automatically controlling reflectance (for example, see Patent Document 2) are known. ing.

  In the prism type anti-glare mirror described in Patent Document 1, the prism mirror is normally positioned vertically, and can reflect the rear view with high reflectance. Further, when the prism mirror is tilted during night driving or the like, the reflectance is lowered, and the amount of light guided into the driver's field of view is reduced. As a result, the driver is prevented from being dazzled by the light of the headlight of the rear vehicle.

In the automatic anti-glare mirror described in Patent Document 2, the mirror reflection surface is covered with an electrochromic element film, and the reflectance is changed by changing the coloring amount of the electrochromic element. Then, the reflectance is controlled to an optimum state by automatic control by an optical sensor built in the mirror. As a result, the rear view is visually recognized by the driver, and the driver is prevented from being dazzled by the light of the headlight of the rear vehicle.
JP-A-10-86749 Japanese Patent Laid-Open No. 9-24768

  By the way, in the rearview mirror (rear view device) using the antiglare mirror described above, the prism mirror is inclined with respect to the light of the headlight of the rear vehicle or the amount of coloring on the mirror reflecting surface changes during night driving. If the anti-glare function is activated by doing so, as shown in FIG. 6, the entire image in the rear view is darkened. For this reason, it is difficult to understand the rear scenery other than the light of the headlight of the rear vehicle, and for example, it may be difficult to recognize a pedestrian or the like. Such a problem exists not only in the rearview mirror but also in the rear viewing device such as a side mirror.

  This invention is made in view of such a situation, and the objective is to provide the back visual recognition apparatus which can visually recognize a back view, preventing the dazzling by the light source of a back view.

Hereinafter, means for achieving the above-described object and its operation and effects will be described.
According to the first aspect of the present invention, there is provided a camera for photographing a rear view, an image processing means for processing an image photographed by the camera, a camera control means for controlling the camera, and an image processed by the image processing means. Image display means for displaying the image, the image processing means detects the luminance of the points constituting the photographed image, outputs luminance information of the detected points to the camera control means, and operates on the image The image processing unit performs image processing for adjusting the brightness so that the driver can visually recognize the rear view with respect to a portion having a predetermined luminance value or more that is set as a feeling that the user feels dazzling. And the camera control means controls the camera so that the driver can visually recognize the rear view based on the luminance information of the portion less than the predetermined luminance value. It has as its gist the Rukoto.

  According to the same configuration, the image processing means detects the luminance of the points constituting the image photographed by the camera, and the driver with respect to a portion of the image having a predetermined luminance value or more that is set to feel dazzling Performs image processing for adjusting the brightness so that the rear view can be visually recognized, and the camera control means controls the camera so that the driver can visually recognize the rear view based on the luminance information of the portion below the predetermined luminance value. That is, when there is a light source that the driver feels dazzling in the rear view, for example, when driving at night, for example, when there is a light from the rear vehicle, the brightness is adjusted based on the luminance information of the entire image in the image taken by the camera. The entire image becomes dark depending on the luminance of the light portion that is equal to or greater than the luminance value. Therefore, the image processing means controls the camera based on the luminance information of the image that is not the light portion that is less than the predetermined luminance value, so that the image that is not the light portion can be appropriately brightened. In addition, the camera control means controls the brightness of the camera according to the image that is not the light part, and since the image of the light part is too bright in this state, the driver can see the rear view from the image of the light part. Adjust the brightness as you can. Thereby, the brightness of the whole image imaged with the camera becomes moderate, and the rear view can be visually recognized while preventing the dazzling by the light of the rear vehicle. Further, by distinguishing an image into two parts and performing image processing on only one part, the processing amount can be reduced as compared with performing different image processing on points constituting each image.

  The gist of the invention according to claim 2 is that, in the backward visual recognition device according to claim 1, the camera control means adjusts at least one of the exposure time and the amount of received light of the camera.

  According to this configuration, the camera control unit adjusts at least one of the exposure time and the amount of received light of the camera based on the luminance of the image detected by the image processing unit. That is, when there is a light source that the driver feels dazzling in the rear view, such as when driving at night, for example, when there is a light from the vehicle behind, at least one of the exposure time and the amount of received light of the camera based on the luminance information of the image that is not the light part By adjusting the image, the image which is not the light portion can be made bright enough for the driver to visually recognize.

  According to a third aspect of the present invention, in the backward visual recognition device according to the first or second aspect, the image processing means performs the image processing only in a predetermined range where a light source frequently appears in an image photographed by the camera. This is the gist.

  According to this configuration, image processing is performed only in a predetermined range where a light source frequently appears in an image taken by a camera. Therefore, when a rear vehicle exists during night driving or the like, the position where the rear vehicle light is present in the rear view is predetermined. The range includes most. Therefore, the amount of image processing can be reduced and the processing speed can be increased.

  ADVANTAGE OF THE INVENTION According to this invention, the back visual recognition apparatus which can visually recognize a back view can be provided, preventing the dazzling by the light source of a back view.

Hereinafter, an embodiment in which a rear view device according to the present invention is embodied in a rearview mirror will be described with reference to FIGS.
As shown in FIG. 1, the backward visual recognition device includes a camera 10 that captures a rear view, an image processing unit 21 that performs processing of an image captured by the camera 10, and a camera that controls the camera 10. The control apparatus 20 provided with the camera control part 22 as a control means, and the back mirror 30 provided with the image display part 31 as an image display means to display an image are provided.

  The camera 10 is a digital camera using a CCD or a CMOS, and is provided inside the rear window of the mounted vehicle 1 as shown in FIG. As shown in FIG. 1, the camera 10 outputs the captured image as image data to the image processing unit 21 of the control device 20. As shown in FIG. 2, the camera 10 can shoot a rear view B in a range including the rear view A projected on the conventional mirror-type rearview mirror, and displays it on the rearview mirror 30. The displayed image has a sufficient viewing angle for the driver to confirm the rear. As shown in FIG. 1, the exposure time and the amount of received light are set for the camera 10 based on control data output from a camera control unit 22 described later.

  The image processing unit 21 detects the luminance of the points constituting the image included in the input image data, and performs image processing on a portion of the image that is equal to or higher than a predetermined luminance value that is set as the driver feels dazzling. . In the image processing, the gain of the image data input from the camera 10 is adjusted and the brightness is adjusted. Then, the image processing unit 21 outputs image data including the image subjected to the image processing to the image display unit 31. Further, the image processing unit 21 outputs detection data including luminance data of the detected image to the camera control unit 22. The camera control unit 22 calculates the exposure time and the amount of received light of the camera 10 based on the luminance data of the image of the portion less than the predetermined luminance value detected by the image processing unit 21 included in the input detection data, and calculates the calculated exposure. Control data for controlling the time and the amount of received light is output to the camera 10. Here, the exposure time and the amount of received light of the camera 10 are obtained by calculating an average value of luminance data of a portion less than a predetermined luminance value detected by the image processing unit 21.

The image display unit 31 provided in the rearview mirror 30 is configured by a liquid crystal display, and displays an image included in the image data input from the image processing unit 21.
Next, the operation | movement aspect of the back visual recognition apparatus comprised as mentioned above is demonstrated with reference to FIG. Here, as shown in FIG. 3, it is assumed that the following vehicle 2 exists behind the mounted vehicle 1 during night driving.

  As shown in FIG. 4, the camera 10 of the mounted vehicle 1 always captures the rear view of the mounted vehicle 1 (step S1). Then, the camera 10 outputs the captured image as image data to the image processing unit 21 of the control device 20. Here, the image taken by the camera 10, that is, the image of the rear view that is not subjected to image processing, is an image in which the light of the following vehicle 2 is dazzling and the driver cannot see the rear view as shown in FIG. is there.

  The image processing unit 21 detects the luminance of the points constituting the image included in the image data input from the camera 10 (step S2). Here, the points constituting the image represent pixels or a certain area. Then, the image processing unit 21 outputs the detected luminance value of the image to the camera control unit 22 as detection data. Further, following step S2, the image processing unit 21 performs image processing on a portion having a luminance value equal to or higher than the luminance value at which the driver feels dazzled based on the luminance value of the point constituting the detected image (step S3). ). Specifically, the image processing unit 21 reduces the lightness in a portion having a predetermined luminance value or more. The image processing unit 21 outputs the image subjected to the image processing as a rear view image, and outputs the rear view image as image data to the image display unit 31.

  On the other hand, when the detection data of the luminance value of the point detected by the image processing unit 21 in step S <b> 2 is input, the camera control unit 22 performs exposure based on the luminance of the image of the portion less than the predetermined luminance value included in the detection data. Time, received light amount, and the like are calculated (step S4). Then, the camera control unit 22 outputs control data including the calculated setting value to the camera 10.

  In the camera 10, the exposure time, the amount of received light, and the like are set according to the set values such as the exposure time and the amount of received light included in the control data input from the camera control unit 22 (step S5). For example, when there is a light of the following vehicle 2 that the driver feels dazzling in the rear view, the exposure time and received light amount of the camera so that the driver can visually recognize the rear view based on the luminance information of the image that is not the light portion. Is set so that the driver can visually recognize an image that is not a light portion. In this way, it is possible to shoot an image that is superior not only in brightness but also in contrast and S / N compared to a general camera in which the exposure time and the amount of received light are controlled based on the luminance information of the entire image. it can.

  The image display unit 31 displays an image included in the image data input from the image processing unit 21 on the image display unit 31 of the rearview mirror 30 (step S6). Specifically, as shown in FIG. 3, the brightness of the light portion of the following vehicle 2 is lowered by the image processing unit 21, and the portion that is not the light portion of the following vehicle 2 is brightened by the camera control unit 22. The person can see the rear view.

  In the above embodiment, the mounted vehicle 1 has been described when traveling at night. However, as a light source that the driver feels dazzling in the rear view of the other mounted vehicle 1, driving can be performed even when sunlight is present during daytime traveling. It is easy for a person to visually recognize the rear view.

As described above, according to the embodiment described above, the following effects can be obtained.
(1) When there is a light of the following vehicle 2 that the driver feels dazzling in the rear view when traveling at night, the image processing unit 21 operates on a light portion that is equal to or higher than a predetermined luminance value in an image captured by the camera. The camera control unit 22 controls the camera so that the driver can visually recognize the rear field of view based on the luminance information of the portion less than the predetermined luminance value while performing image processing for adjusting the brightness so that the user can visually recognize the rear field of view. . For this reason, the entire image is not darkened according to the luminance of the light part, and the rear view can be visually recognized while preventing the dazzling of the light of the succeeding vehicle 2. Further, by distinguishing an image into two parts and performing image processing on only one part, the processing amount can be reduced as compared with performing different image processing on points constituting each image.

  (2) The camera control unit 22 adjusts the exposure time and received light amount of the camera 10 based on the luminance of the image detected by the image processing unit 21. That is, by adjusting the exposure time and received light amount of the camera 10 based on the luminance information of the image that is not the light part when there is a light of the following vehicle 2 that the driver feels dazzling in the rear view when traveling at night, An image that is not a light portion can be made bright enough for the driver to see.

In addition, the said embodiment can be implemented with the following forms which changed this suitably.
In the above embodiment, the camera control unit 22 is provided in the control device 20, but the camera control unit 22 may be provided integrally with the camera 10.

  In the above embodiment, the camera 10 is fixed facing backward, but the direction of the camera 10 may be changed by operating a switch. That is, when the driver operates a switch provided in the image display unit 31 or the like, the direction of the camera 10 is changed by the driving device provided in the camera 10.

  In the above embodiment, the camera 10 is fixed facing the rear of the mounted vehicle 1, but the direction of the camera 10 may be changed in conjunction with the direction of the driver. That is, the orientation of the driver's face is detected, and the orientation of the camera 10 is changed by the driving device provided in the camera 10 according to the orientation of the face.

  In the above embodiment, the camera 10 is fixed facing the rear of the mounted vehicle 1, but the direction of the camera 10 may be changed in conjunction with the steering angle of the steering wheel. That is, the steering wheel of the mounted vehicle 1 is steered by the driver when traveling on a curve. At this time, the direction of the camera 10 is changed by the drive device provided in the camera 10 based on the output from the detection device that detects the steering angle of the steering wheel. Then, when the camera 10 has taken a range indicated by a broken line in FIG. 7 during straight running, a range indicated by a solid line in FIG. 7 is taken. In this way, the rear view displayed on the image display unit 31 can always display the range in which the mounted vehicle 1 has traveled, and the rear view on the road can always be visually recognized.

  In the above embodiment, the camera 10 is provided on the indoor side of the rear window of the mounted vehicle 1, but may be provided on the rearview mirror 30. In this way, since the camera 10 and the rearview mirror 30 can be integrated, installation work can be facilitated.

  In the above embodiment, the camera 10 is provided on the indoor side of the rear window of the mounted vehicle 1, but the camera 10 may be provided on the side surface of the mounted vehicle 1. Further, the camera 10 may be provided on a side mirror of the mounted vehicle 1.

  In the above embodiment, the image display unit 31 is provided on the rearview mirror 30, but a navigation display screen may be used. Further, the camera of the back monitor that displays the vicinity of the rear side of the mounted vehicle 1 when reversing and the camera 10 of the rear viewing device may be shared. In this way, it is not necessary to provide a plurality of cameras, and installation work can be reduced. Note that the shared camera is a wide-angle camera that can capture both image ranges, or the shared camera is provided with a drive device such as a zoom lens that can change the shooting range, or the shared camera has a shooting direction that matches the display range. It is necessary to provide a driving device so that it can be changed.

In the above embodiment, the image display unit 31 is provided on the rearview mirror 30, but may be provided on the instrument panel.
In the above embodiment, the present invention is applied to the rearview mirror 30, but may be applied to a side mirror.

  In the above embodiment, the camera control unit 22 controls the exposure time and the amount of received light of the camera 10 based on the detection data of the image processing unit 21. However, only one of them may be controlled. Further, the exposure time and the amount of received light of the camera 10 are not changed as long as the image of the rear view is visible to the driver only by the image processing of the image processing unit 21 regardless of the adjustment of the exposure time and the amount of received light of the camera 10. You may do it.

  In the above embodiment, the image processing unit 21 performs image processing on an image of a portion of the entire image that is equal to or higher than the predetermined luminance value, but an image range in which the light of the following vehicle 2 frequently appears is assumed in advance. In such a case, image processing may be performed only within a predetermined range. In this way, since the image processing range can be reduced, the processing amount of the image processing unit 21 can be reduced and the processing speed can be increased.

Next, technical ideas other than the claimed invention that can be grasped from the embodiment will be described together with the effects thereof.
(A) The backward visual recognition device according to any one of claims 1 to 3, further comprising: a steering angle detection unit that detects a steering angle of a steering wheel; and a driving unit that changes a shooting direction of the camera. A backward visual recognition device that changes the direction of the camera based on a steering angle detected by a steering angle detection means. According to this configuration, the shooting direction of the camera is changed based on the steering angle of the steering wheel. In other words, when the vehicle is running on a curve, the rear view displayed on the image display means always shows the range in which the vehicle has traveled by changing the direction of the camera so that it always captures the road on which the vehicle has traveled in accordance with the steering wheel of the vehicle. It can be displayed, and the rear view on the road can always be visually recognized.

The block diagram which shows schematic structure of a back visual recognition apparatus. The figure which shows the back visual field image | photographed with a camera. The figure which shows the mounting vehicle and subsequent vehicle which mount a back visual recognition apparatus. The sequence chart which shows the processing operation of a back visual recognition apparatus. The figure which shows the image of the back view image | photographed with the camera. The figure which shows the back visual field by the conventional back visual recognition apparatus. The figure which shows the imaging | photography range by the camera at the time of curve driving | running | working.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Mounted vehicle, 2 ... Subsequent vehicle, 10 ... Camera, 20 ... Control apparatus, 21 ... Image processing part, 22 ... Camera control part, 30 ... Rearview mirror, 31 ... Image display part.

Claims (3)

A camera that captures a rear view, an image processing unit that processes an image captured by the camera, a camera control unit that controls the camera, and an image display unit that displays an image processed by the image processing unit ,
The image processing means detects a brightness of a point constituting the photographed image, outputs brightness information of the detected point to the camera control means, and is set as a predetermined feeling that the driver feels dazzling in the image While performing image processing to adjust the brightness so that the driver can visually recognize the rear view for the portion of the luminance value or higher, and output the image subjected to the image processing to the image display means,
The rear visual recognition device, wherein the camera control means controls the camera so that a driver can visually recognize a rear view based on luminance information of a portion less than the predetermined luminance value. The backward visual recognition device according to claim 1,
The rear visual recognition device, wherein the camera control means adjusts at least one of an exposure time and a received light amount of the camera. The backward visual recognition device according to claim 1 or 2,
The backward viewing device, wherein the image processing means performs the image processing only in a predetermined range where a light source frequently appears in an image taken by the camera.

Images