Abstract:
Provided is an image capturing device. 
     The image capturing device includes: a parameter setting section that automatically sets, (A) during ordinary times, a setting parameter for image-capturing to a value that depends on brightness of an image-capturing environment, and that sets, (B) at a time of the adjusting of the optical axis, the setting parameter to a predetermined adjustment setting value; a setting value receiving section that receives the adjustment setting value from the adjusting device when the adjusting of the optical axis is initiated; and an optical axis adjusting section that adjusts the optical axis based on an image captured in a state where the setting parameter is set to be the adjustment setting value. The adjusting device includes: a setting value storing section that stores the adjustment setting value in advance; and a setting value transmitting section that transmits the adjustment setting value to the image capturing device.

Description:
TECHNICAL FIELD 
       [0001]    The present invention relates to an image capturing device, an adjusting device, and an optical axis adjusting system for the image capturing device; and more specifically, relates to an image capturing device, an adjusting device, and an optical axis adjusting system for the image capturing device for adjusting an optical axis based on a captured image of a target. 
       BACKGROUND ART 
       [0002]    In recent years, there are vehicles having mounted thereon cameras for acquiring images of the peripheries of the vehicles. The cameras are mounted for acquiring images of the forward direction of the vehicles so as to be used, for example, for traffic lane recognition, preceding vehicle recognition, and the like. When attaching such a camera to a vehicle, misalignment of an optical axis direction occurs with respect to the traveling direction of the vehicle when attaching the camera due to mechanical factors and control-technological factors. A misalignment in the optical axis direction of the camera can lead to cases where a desired image cannot be obtained due to shifting in focus or not being able to capture a desired range for image-capturing. Therefore, an optical axis adjustment of a mounted camera is performed for every vehicle at a manufacturing plant of the vehicle, at a dealer, and the like. Known methods for adjusting the optical axis include, for example, a method disclosed in Patent Literature I of capturing, with a camera, an image of a target whose positional relationship with the vehicle has been established in advance. In the optical axis adjusting method disclosed in Patent Literature 1, a target having a white part and a black part is captured as an image by a camera, and an optical axis is adjusted by matching the center of the optical axis of the camera to the center of the target defined by a boundary line between the white part and the black part. 
       CITATION LIST 
     Patent Literature  
       [0003]    [PTL 1] Japanese Laid-Open Patent Publication No. 2005-143040 
       SUMMARY OF THE INVENTION 
     Problems to be Solved by the Invention 
       [0004]    However, the above described optical axis adjusting method has the following problem. When capturing an image, in order to capture a fine image, the camera mounted on the vehicle generally automatically adjusts exposure such as a gain, an electronic shutter, and the like in accordance with an image-capturing environment of whether it is in a bright location or a dark location and the like. On the other hand, the image-capturing environments in different factories or the like where the optical axis adjustments of the cameras are conducted are not uniform. Therefore, when the optical axis adjustment of the camera is conducted, the camera performs an exposure control in accordance with an image-capturing environment at one of such factories. 
         [0005]    For example, when the background of a target is dark, the camera performs the exposure control so as to brighten the background of the target. In such a case, the white part of the target becomes saturated (i.e., halation occurs), and an area of the white part in an image may be captured as being larger than the actual area. When this happens, the boundary line between the white part and the black part cannot be detected accurately, and the center position of the target may be detected inaccurately. When the optical axis adjustment is conducted so as to match the optical axis to the inaccurately detected center position of the target, the optical axis may not be adjusted to an accurate position. 
         [0006]    The present invention has been made in view of the above described problem, and an objective of the present invention is to provide an image capturing device and an optical axis adjusting system for the image capturing device enabling an accurate optical axis adjustment. 
       Solution to the Problems 
       [0007]    In order to solve the above described problem, the following configuration is employed in the present application. That is, a first aspect of the present invention is an optical axis adjusting system for adjusting an optical axis of an image capturing device mounted on a vehicle that captures an image of a periphery of the vehicle. The optical axis adjusting system for the image capturing device includes the image capturing device and an adjusting device communicably connected to the image capturing device. The image capturing device includes: a parameter setting section configured to, (A) during ordinary times, set a setting parameter for image-capturing to a value that depends on a brightness of an image-capturing environment, and, (B) at a time of the adjusting of the optical axis, set the setting parameter to a predetermined adjustment setting value; a setting value receiving section configured to receive the adjustment setting value from the adjusting device when the adjusting of the optical axis is initiated; and an optical axis adjusting section configured to adjust the optical axis based on an image captured in a state where the setting parameter is set to be the adjustment setting value. The adjusting device includes: a setting value storing section configured to store the adjustment setting value in advance; and a setting value transmitting section configured to transmit the adjustment setting value to the image capturing device. 
         [0008]    In a second aspect based on the first aspect, the adjusting device further includes an input section configured to accept an input operation by a user, and a setting value changing section configured to change the adjustment setting value stored in the setting value storing section, in accordance with the input operation by the user. 
         [0009]    In a third aspect based on the second aspect, the image capturing device further includes: an adjustment result determining section configured to determine, after the adjusting of the optical axis, whether or not the adjusting of the optical axis has been conducted properly; an image brightness calculating section configured to, when it has been determined that the adjusting of the optical axis has not been conducted properly, calculate an image brightness indicating a brightness of an image captured at a time of the adjusting of the optical axis; and an image brightness transmitting section configured to transmit the image brightness to the adjusting device. In addition, the adjusting device further includes: an image brightness receiving section configured to receive the image brightness; and a display section configured to display the image brightness. 
         [0010]    In a fourth aspect based on the third aspect, the image brightness calculating section calculates an average luminance value of the image captured at the time of the adjusting of the optical axis, and calculates the image brightness as a value in accordance with the average luminance value. 
         [0011]    In a fifth aspect based on the third aspect, the optical axis adjusting section adjusts the optical axis based on a captured image of a target arranged in a forward direction of the image capturing device in a state where the setting parameter is set to be the adjustment setting value, and the image brightness calculating section calculates an average luminance value of an image area representing the target within the image captured at the time of the adjusting of the optical axis, and calculates the image brightness as a value in accordance with the average luminance value. 
         [0012]    In a sixth aspect based on the first aspect, the setting parameter at least includes an exposure time for the image capturing device. 
         [0013]    In a seventh aspect based on the first aspect, the setting parameter includes an aperture value for an aperture member that limits an incident light volume of the image capturing device. 
         [0014]    In an eighth aspect based on the first aspect, the optical axis adjusting section adjusts the optical axis based on a captured image of a target arranged in a forward direction of the image capturing device in a state where the setting parameter is set to be the adjustment setting value. 
         [0015]    A ninth aspect is an image capturing device mounted on a vehicle and included in an optical axis adjusting system for adjusting an optical axis of the image capturing device that captures an image of a periphery of the vehicle. The image capturing device includes: a parameter setting section configured to, (A) during ordinary times, set a setting parameter for image-capturing to a value that depends on a brightness of an image-capturing environment, and, (B) at a time of the adjusting of the optical axis, set the setting parameter to a predetermined adjustment setting value; and an optical axis adjusting section configured to adjust the optical axis based on an image captured in a state where the setting parameter is set to be the adjustment setting value. 
         [0016]    A tenth aspect is an adjusting device included in an optical axis adjusting system for adjusting an optical axis of an image capturing device that is mounted on a vehicle and that captures an image of a periphery of the vehicle. The adjusting device includes: a setting value storing section configured to store, in advance, an adjustment setting value that is used as a value of a setting parameter for image-capturing when the adjusting the optical axis of the image capturing device is conducted; and a setting value transmitting section configured to transmit the adjustment setting value to the image capturing device. 
         [0017]    An eleventh aspect is an image capturing device that is mounted on a vehicle and that is for capturing an image of a periphery of the vehicle. The image capturing device includes: a parameter setting section configured to, (A) during ordinary times, automatically set a setting parameter for image-capturing to a value that depends on a brightness of an image-capturing environment, and, (B) at a time of adjusting an optical axis, set the setting parameter to a predetermined adjustment setting value; and an optical axis adjusting section configured to adjust the optical axis based on an image captured in a state where the setting parameter is set to be the adjustment setting value. 
       Advantageous Effects of the Invention 
       [0018]    With the first aspect of the present invention, the optical axis of the image capturing device can be adjusted accurately. Specifically, when adjusting the optical axis of the image capturing device, the setting parameter for image-capturing is fixed to an adjustment setting value. Therefore, the setting parameter for image-capturing will not be changed in accordance with the brightness of the surrounding environment, and thereby, will not be influenced by the surrounding environment. As a result, for example, an image of an object that is used as a standard target for an optical axis adjustment can be captured clearly. Consequently, the optical axis can be adjusted accurately based on the image that has been captured clearly 
         [0019]    With the second aspect of the present invention, the adjustment setting value can be changed as appropriate to an arbitrary value set by the user. For example, one envisioned situation is a case where multiple image capturing devices are continuously or simultaneously adjusted at a manufacturing plant or the like. In this case, the multiple image capturing devices each can acquire adjustment setting values from the identical adjusting device. Therefore, when the user once changes the adjustment setting value by using the adjusting device, the adjustment setting values used by each of the image capturing devices at the time of adjusting can be changed all at once. As a result, the user can change the adjustment setting values used by each of the multiple image capturing devices at the time of adjusting, with a small number of operation steps. 
         [0020]    With the third aspect of the present invention, the user can confirm the brightness (image brightness) of the image captured at the time of the optical axis adjustment. Therefore, the user can change the setting parameter for image-capturing in accordance with the image brightness. For example, when the image brightness is relatively high and when it is thought that halation can easily occur, the user can change the adjustment setting value so as to lower the brightness of the captured image. 
         [0021]    With the fourth aspect of the present invention, the image brightness can be calculated using a simple process. 
         [0022]    With the fifth aspect of the present invention, the brightness of the target in the captured image is displayed as the image brightness. Therefore, the user can confirm a numerical value of the image brightness and then can determine whether or not the brightness of the target in the captured image is at an easily recognizable level. 
         [0023]    With the sixth aspect of the present invention, the exposure time of the image capturing device can be set to be the adjustment setting value at the time of the optical axis adjustment. As a result, at the time of the optical axis adjustment, the brightness of the image captured by the image capturing device can be arbitrarily and easily adjusted. 
         [0024]    With the seventh aspect of the present invention, the aperture value of the aperture member included in the image capturing device can be set to be the adjustment setting value at the time of the optical axis adjustment. As a result, at the time of the optical axis adjustment, the brightness of the image captured by the image capturing device can be arbitrarily and easily adjusted. 
         [0025]    With the eighth aspect of the present invention, the optical axis of the image capturing device can be adjusted using a simple process, based on the position of the target in the image captured by the image capturing device. 
         [0026]    With the image capturing device according to the ninth aspect of the present invention and the adjusting device according to the tenth aspect, the optical axis adjusting system according to the first aspect can be formed, and thereby an advantageous effect identical to the optical axis adjusting system can be obtained. 
         [0027]    With the adjusting device according to the eleventh aspect of the present invention, the setting parameter can be changed without communicating with another instrument, and the optical axis of the image capturing device can be adjusted accurately. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0028]      FIG. 1  is a block diagram showing a configuration of an optical axis adjusting system  1  according to a first embodiment. 
           [0029]      FIG. 2  is a side view of a vehicle  30  arranged at a vehicle original position. 
           [0030]      FIG. 3  is a front view of a target  50 . 
           [0031]      FIG. 4  is a flowchart showing processes executed by a camera-control ECU  12  and an equipment computer  21  according to the first embodiment. 
           [0032]      FIG. 5  shows the rest of the flowchart showing the processes executed by the camera-control ECU  12  and the equipment computer  21  according to the first embodiment. 
           [0033]      FIG. 6  shows one example of an abnormality screen displayed on a display  22  when an optical axis adjustment has been terminated due to an abnormality. 
           [0034]      FIG. 7  is a block diagram showing a configuration of an image capturing device  40  according to a second embodiment. 
           [0035]      FIG. 8  is a flowchart showing processes executed by a camera-control ECU  61  according to the second embodiment. 
       
    
    
     DESCRIPTION OF EMBODIMENTS 
       [0036]    First Embodiment 
         [0037]    Descriptions are provided in the following with reference to  FIG. 1  to  FIG. 6  for an image capturing device  10  and an optical axis adjusting system  1  of the image capturing device according to the first embodiment of the present invention. 
         [0038]    First, with reference to  FIG. 1 , a configuration of the optical axis adjusting system  1  will be described.  FIG. 1  is a block diagram showing the configuration of the optical axis adjusting system  1  according to the first embodiment. As shown in  FIG. 1 , the optical axis adjusting system  1  includes an image capturing device  10  and adjusting equipment  20 . The image capturing device  10  includes an on-board camera  11  and a camera-control ECU  12 . In addition, the adjusting equipment  20  includes an equipment computer  21 , a liquid crystal display  22 , a touch panel  23 , a buzzer  24 , and a transport device  25 . Described in the following is an example in which the image capturing device  10  is mounted on a vehicle  30 . 
         [0039]    The on-board camera  11  is, for example, a camera including a lens and an image sensor such as a CCD (Charge Coupled Device) sensor, a CMOS (Complementary Metal Oxide Semiconductor) sensor, and the like. The on-board camera  11  is communicably connected to the camera-control ECU  12 , and changes settings for image-capturing in response to instructions from the camera-control ECU  12 . Specifically, the on-board camera  11  changes a value of an exposure time T in response to an instruction from the camera-control ECU  12 . The exposure time T is the time period the image sensor is exposed when the on-board camera  11  captures an image. In addition, the on-board camera  11  outputs data representing a captured image to the camera-control ECU  12 . It should be noted that, in the following, an image captured by the on-board camera  11  is referred to as a camera image. 
         [0040]    Representatively, the camera-control ECU  12  is a control device including an information processing device such as a CPU (Central Processing Unit), a storage device such as a memory, an interface circuit, and the like. The camera-control ECU  12  is communicably connected to the equipment computer  21 , and executes an optical axis adjustment of the on-board camera  11  in accordance with an instruction signal and data received from the equipment computer  21 . The camera-control ECU  12  and the equipment computer  21  may be mutually connected with a communication method of either a wireless communication or a wired communication. Details of processes for the camera-control ECU  12  will be described later. 
         [0041]    Representatively, the equipment computer  21  is a control device including an information processing device such as a CPU (Central Processing Unit), a storage device such as a memory, an interface circuit, and the like. The equipment computer  21  operates the liquid crystal display  22 , the buzzer  24 , and the transport device  25 , in accordance with an input operation by the user via the touch panel  23 , and a signal received from the camera-control ECU  12 , and the like. 
         [0042]    Representatively, the display  22  is a display device capable of displaying an image, such as a liquid crystal display. The display  22  displays various information and button images for operating the adjusting equipment  20  in response to an instruction from the equipment computer  21 . 
         [0043]    The touch panel  23  is an input device for accepting an input operation on the equipment computer  21  by the user. The touch panel  23  is arranged so as to cover a screen of the display  22  and to allow display contents on the screen to pass through. The user performs a touch input on a button displayed on the screen of the display  22  via the touch panel  23 , and causes the equipment computer  21  to execute an operation corresponding to the button. It should be noted that various types of touch panels may be used as the touch panel  23 , including an electrostatic type, a pressure-sensitive type, an infrared sensing type, and the like. 
         [0044]    The buzzer  24  is an audio output device for generating a warning sound. The buzzer  24  is connected to the equipment computer  21 . The buzzer  24  generates a warning sound in response to an instruction from the equipment computer  21 . 
         [0045]    The transport device  25  is a device for transporting the vehicle  30  to a predetermined position (hereinafter, referred to as a vehicle original position) for executing the optical axis adjustment. The transport device  25  is connected to the equipment computer  21 . The transport device  25  transports the vehicle  30  into the vehicle original position and transports the vehicle  30  out from the vehicle original position in response to an instruction from the equipment computer  21 . In addition, when the vehicle  30  is transported into the vehicle original position, the transport device  25  outputs, to the equipment computer  21 , an arrangement completion signal indicating that the vehicle  30  has been arranged at the vehicle original position. 
         [0046]      FIG. 2  is a side view of the vehicle  30  arranged at the vehicle original position by the transport device  25 . As shown in  FIG. 2 , the vehicle  30  is arranged at the vehicle original position such that the on-board camera  11  and a target  50  face each other. It should be noted that the mounted position of the on-board camera  11  is one example. The on-board camera  11  may be mounted at any position of the vehicle  30  as long as it is arranged so as to face the target  50  at the vehicle original position. 
         [0047]      FIG. 3  is a front view of the target  50 . The target  50  according to the present embodiment is a plate-like member as shown in  FIG. 2  and  FIG. 3 . A lattice pattern in which white and black areas are alternately arranged is drawn on a plate surface of the target  50 . It should be noted that the above described shape and pattern of the target  50  are those of one example, and an object having any shape and pattern may be used as the target as long as it is an object that can be captured as an image by the on-board camera  11  as a standard for axis adjustment. 
         [0048]    Next, with reference to  FIG. 4  and  FIG. 5 , processes executed by the camera-control ECU  12  and the equipment computer  21  will be described.  FIG. 4  and  FIG. 5  show a flowchart indicating the processes executed by the camera-control ECU  12  and the equipment computer  21  according to the first embodiment. The camera-control ECU  12  executes a camera control process shown in  FIG. 4 . Furthermore, the equipment computer  21  executes an equipment control process shown in  FIG. 4  and  FIG. 5 . 
         [0049]    When the equipment computer  21  initiates the equipment control process shown in  FIG. 4 , first, the equipment computer  21  determines whether or not the vehicle  30  has been transported into the vehicle original position (step B 1 ). Specifically, the equipment computer  21  determines whether or not the arrangement completion signal has been received from the transport device  25 . When the equipment computer  21  has not received the arrangement completion signal from the transport device  25 , the equipment computer  21  determines that the vehicle  30  has not been transported into the vehicle original position (“No” at step B 1 ), and waits until the arrangement completion signal is received. While the equipment computer  21  is waiting, the transport device  25  transports the vehicle  30  into the vehicle original position. On the other hand, when the equipment computer  21  receives the arrangement completion signal from the transport device  25 , the equipment computer  21  determines that the vehicle  30  has been transported into the vehicle original position (“Yes” at step B 1 ), and transmits an adjustment setting value TA to the camera-control ECU  12  (step B 2 ). 
         [0050]    When the camera-control ECU  12  initiates the camera control process shown in  FIG. 4 , first, the camera-control ECU  12  determines whether or not the adjustment setting value TA has been received from the equipment computer  21  (step A 1 ). When the camera-control ECU  12  has not received the adjustment setting value TA (“No” at step A 1 ), the camera-control ECU  12  conducts an ordinary image capturing process (from step A 2  to step A 3 ). Specifically, first, the camera-control ECU  12  automatically sets the exposure time T (step A 2 ). In more detail, the camera-control ECU  12  acquires a camera image captured by the on-board camera  11 . Then, the camera-control ECU  12  calculates an average luminance value of the camera image, and sets the exposure time T shorter as the average luminance value becomes larger, and sets the exposure time TA longer as the average luminance value becomes smaller. Next, the camera-control ECU  12  causes the on-board camera  11  to capture a camera image, and acquires the camera image (step A 3 ). Additionally at step A 3 , the camera-control ECU  12  transmits data of the acquired camera image to an instrument (not shown) that conducts controls using the image data. When the process at step A 3  is completed, the camera-control ECU  12  returns the process to step A 1 , and repeatedly executes the above described processes at step A 2  and step A 3  until the adjustment setting value TA is received. 
         [0051]    With the above described processes from step Al to step A 3 , when the optical axis adjustment has not been conducted, the exposure time T is automatically set in accordance with the brightness of an image-capturing environment. 
         [0052]    On the other hand, when the camera-control ECU  12  receives the adjustment setting value TA (“Yes” at step A 1 ), the camera-control ECU  12  conducts a control process for the optical axis adjustment (from step A 4  to step A 9 ). First, the camera-control ECU  12  sets the value of the exposure time T to the adjustment setting value TA (step A 4 ). Next, the camera-control ECU  12  executes the optical axis adjustment for the on-board camera  11  (step AS). Specifically, the camera-control ECU  12  acquires a camera image from the on-board camera  11 , and detects a central point of the target  50  in the camera image. Then, the optical axis of the on-board camera  11  is adjusted by shifting an image-capturing range of the camera image such that the central point is positioned within a predetermined area of the camera image (hereinafter, referred to as a target acquisition area). It should be noted that the above described method for optical axis adjustment is one example, and the optical axis of the on-board camera  11  may be adjusted using a conventionally known method, as long as the camera-control ECU  12  conducts the optical axis adjustment based on the camera image. 
         [0053]    With the above described processes at step A 4  and step AS, when conducting the optical axis adjustment, the exposure time T is fixed to the adjustment setting value TA. As a result, the camera-control ECU  12  can execute the optical axis adjustment without being influenced by the brightness of the image-capturing environment. 
         [0054]    When the camera-control ECU  12  completes the process at step A 5 , the camera-control ECU  12  determines whether or not the axis adjustment has been completed properly (step A 6 ). For example, the camera-control ECU  12  acquires a camera image from the on-board camera  11 , and determines whether or not the center of the target  50  is captured in the target acquisition area of the camera image. Then, when the center of the target  50  is captured in the target acquisition area of the camera image, the camera-control ECU  12  determines that the axis adjustment has been completed properly (“Yes” at step A 6 ), and transmits an adjustment-completion signal to the equipment computer  21  (step A 7 ). The adjustment-completion signal is a signal indicating that the optical axis adjustment of the on-board camera  11  has been completed properly. On the other hand, when the center of the target  50  is not captured in the target acquisition area of the camera image, the camera-control ECU  12  determines that the axis adjustment has not been completed properly (“No” at step A 6 ), and calculates an image brightness L (step A 8 ). The image brightness L is a parameter indicating the brightness of the camera image. The camera-control ECU  12  detects, for example, the target  50  in the camera image acquired at step A 6 . Then, the camera-control ECU  12  calculates, as the image brightness L, an average luminance value of an area representing the target  50  in the camera image. When the camera-control ECU  12  calculates the image brightness L, the camera-control ECU  12  transmits data representing the image brightness L to the equipment computer  21 . 
         [0055]    It should be noted that the above described method shown at step A 6  is one example, and the camera-control ECU  12  may determine whether or not the optical axis adjustment has been completed properly by using any conventionally known method. 
         [0056]    After the equipment computer  21  executes a process for transmitting the adjustment setting value TA (step B 2 ), the equipment computer  21  determines whether or not the adjustment-completion signal or the image brightness L has been received (step B 3  and step B 5 ). More specifically, when the adjustment-completion signal has not been received (“No” at step B 3 ), the equipment computer  21  determines whether or not the image brightness L has been received (step B 5 ). If the equipment computer  21  has not received the adjustment-completion signal or the image brightness L (“No” at step B 3 , and “No” at step B 5 ), the equipment computer  21  waits until either the adjustment-completion signal or the image brightness L is received. When the equipment computer  21  receives the adjustment-completion signal (“Yes” at step B 3 ), the equipment computer  21  operates the transport device  25  and transports the vehicle  30  out from vehicle original position (step B 4 ). On the other hand, when the equipment computer  21  has not received the adjustment-completion signal but receives the image brightness L (“No” at step  133  and “Yes” at step B 5 ), the equipment computer  21  executes a process to deal with an abnormality during adjustment (from step B 6  to step B 11 ). 
         [0057]    First, the equipment computer  21  informs the user that the optical axis adjustment of the on-board camera  11  has been terminated due to an abnormality (step B 6 ). Specifically, the equipment computer  21  outputs a warning sound from the buzzer  24 . In addition, the equipment computer  21  causes the display  22  to display an image indicating that the adjustment has not been completed. For example, the equipment computer  21  displays an abnormality screen on the display  22  as shown in  FIG. 6 .  FIG. 6  shows one example of the abnormality screen displayed on the display  22  when the optical axis adjustment is terminated due to an abnormality. In addition, the equipment computer  21  displays, on the display  22 , the value of the image brightness L received from the camera-control ECU  12  (step B 7 ). 
         [0058]    Furthermore, the equipment computer  21  accepts, on the abnormality screen, an operation for changing the setting of the adjustment setting value TA by the user (step B 8 ). Specifically, the equipment computer  21  displays on the display  22  a button image for numerical inputs, such as a numerical keypad image K (cf.  FIG. 6 ). Then, by detecting a touch input to the numerical keypad image K using the touch panel  23 , the equipment computer  21  accepts a numerical input from the user. While accepting a setting for the adjustment setting value TA, the equipment computer  21  determines whether or not the setting has been completed (step B 9 ). Specifically, the equipment computer  21  determines whether or not a touch input on a setting button E on the abnormality screen shown in  FIG. 6  has been detected. When the equipment computer  21  has not detected the touch input to the setting button E, the equipment computer  21  determines that the setting of the adjustment setting value TA has not been completed (“No” at step B 9 ), and waits until the touch input to the setting button E is detected. On the other hand, when the equipment computer  21  detects the touch input to the setting button E, the equipment computer  21  determines that the setting of the adjustment setting value TA has been completed (“Yes” at step  89 ), and stores, in a storage device of the equipment computer  21 , the above described numerical value accepted at step B 8  as a value of the adjustment setting value TA (step B 10 ). 
         [0059]    With the above described processes from step B 5  to step B 10 , the user can set the adjustment setting value TA to an arbitrary value while referring to the value of the image brightness L, since the value of the image brightness L is displayed on the abnormality screen. For example, when the image brightness is relatively high and when it is thought that halation can easily occur, the user can change the adjustment setting value so as to lower the brightness of the captured image. 
         [0060]    Furthermore, with the above described process at step A 8 , since the brightness of the target  50  in the camera image is calculated as the image brightness L, the user can confirm the image brightness L and can determine whether or not the target  50  in the camera image is captured with brightness at an easily recognizable level. When there is a desire to confirm the brightness of the whole camera image instead of only the brightness of the target  50 , the camera-control ECU  12  may, for example, calculate an average luminance value of the whole camera image as the image brightness L at step A 8 . 
         [0061]    When the equipment computer  21  completes the process at step B 10 , the equipment computer  21  determines whether or not restarting of an automated operation has been instructed by the user (step B 11 ). The equipment computer  21  determines whether or not a touch input to an operation-start button G has been detected on the abnormality screen shown in  FIG. 6 . When the equipment computer  21  has not detected the touch input to the operation-start button G, the equipment computer  21  determines that restarting of the automated operation has not been instructed (“No” at step B 11 ), and waits until the touch input to the operation-start button G is detected. On the other hand, when the equipment computer  21  detects a touch input to the operation-start button G, the equipment computer  21  determines that setting of the adjustment setting value TA has been completed (“Yes” at step B 11 ), returns the process to step B 1 , and repeatedly executes the above described processes from step B 1  to step B 11 . 
         [0062]    By having the equipment computer  21  and the camera-control ECU  12  repeat the above described processes, the optical axis adjustment of the on-board camera  11  mounted on the vehicle can be executed continuously and automatically. 
         [0063]    As described above, with the optical axis adjusting system  1  according to the present invention, when adjusting the optical axis of the on-board camera  11 , adjustment of the optical axis is executed by fixing the value of the exposure time T to the adjustment setting value TA. As a result, at the time of the optical axis adjustment, the on-board camera  11  can clearly capture an image of the target  50  without being influenced by the brightness of the surrounding environment. Then, since the optical axis of the on-board camera  11  is adjusted based on the camera image captured clearly, the adjustment of the optical axis can be executed accurately. 
         [0064]    It should be noted that, in the above described first embodiment, an example has been described in which the equipment computer  21  and the camera-control ECU  12  set the exposure time T of the on-board camera  11  to the adjustment setting value TA at the time of the optical axis adjustment. However, the present invention is not limited to the exposure time T, and the equipment computer  21  and the camera-control ECU  12  may set other parameters involved in the brightness of the camera image. For example, when the on-board camera  11  includes an aperture member for automatically controlling an incident light volume, the equipment computer  21  and the camera-control ECU  12  may control an aperture value of the aperture member. Specifically, when adjusting the optical axis, the equipment computer  21  transmits a setting value SA for the aperture value for optical axis adjustment to the camera-control ECU  12 . Then, the camera-control ECU  12  sets the aperture value to the received setting value SA and executes the optical axis adjustment. Similarly, the equipment computer  21  and the camera-control ECU  12  may control a gain value of the on-board camera  11 . 
         [0065]    Furthermore, in the first embodiment, an example has been described in which the touch panel  23  is included in the adjusting equipment  20  as a device for accepting an input operation by the user. However, the adjusting equipment  20  may include another input device instead of the touch panel  23 . For example, the adjusting equipment  20  may be formed by substituting the touch panel  23  with an input device such as a mouse or a keyboard. Furthermore, when the vehicle  30  is transported by a person, it is possible to not include the transport device  25  in the adjusting equipment  20 . 
         [0066]    Furthermore, in the first embodiment, an example has been described in which the optical axis adjusting system  1  includes the image capturing device  10  and the adjusting equipment  20 . However, the optical axis adjusting system  1  may be formed from a small size terminal device having the same functions as the image capturing device  10  and the adjusting equipment  20 . For example, the optical axis adjusting system may be configured by communicably connecting, to the image capturing device  10 , a laptop personal computer capable of conducting the same control process of the equipment computer  21 . Such configuration is suitable when conducting the optical axis adjustment of the image capturing device  10  in an environment where arranging a large equipment is difficult, such as in a repair shop, for example. 
         [0067]    Furthermore, in the first embodiment, an example has been described in which the equipment computer  21  stores the value of the adjustment setting value TA and transmits the adjustment setting value TA to the camera-control ECU  12  when executing the optical axis adjustment. However, the camera-control ECU  12  may store therein the value of the adjustment setting value TA in advance. Specifically, at the above described step B 2 , the equipment computer  21  only transmits, to the camera-control ECU  12 , a signal indicating an instruction to initiate the adjustment. The camera-control ECU  12  determines at step Al whether or not the signal indicating the instruction to initiate the adjustment has been received. Then, when the camera-control ECU  12  determines that the signal indicating the instruction to initiate the adjustment has been received, the camera-control ECU  12  reads out at step B 4  the value of the adjustment setting value TA stored in its own storage device, and sets the value of the exposure time T for the on-board camera  11  to the adjustment setting value TA. By having such a configuration and by conducting such processes, data volume transmitted from the equipment computer  21  to the camera-control ECU  12  and storage area necessary for the equipment computer  21  can be reduced. 
         [0068]    Second Embodiment 
         [0069]    In the first embodiment, an example has been described in which the adjustment setting value TA is stored and changed by the adjusting equipment  20 . However, the value of the adjustment setting value TA may be stored and changeable by a device mounted on the vehicle  30 . In the following, an image capturing device  40  according to a second embodiment will be described. 
         [0070]    As shown in  FIG. 7 , the image capturing device  40  according to the second embodiment includes an on-board camera  60 , a camera-control ECU  61 , a display  62 , a touch panel  63 , and a buzzer  64 .  FIG. 7  is a block diagram showing a configuration of the image capturing device according to the second embodiment. It should be noted that the image capturing device  40  is mounted on the vehicle  30 . 
         [0071]    The on-board camera  60 , the camera-control ECU  61 , the display  62 , the touch panel  63 , and the buzzer  64  are devices similar to the display  22 , the touch panel  23 , and the buzzer  24  according to the first embodiment in terms of hardware. However, the camera-control ECU  61 , the display  62 , the touch panel  63 , and the buzzer  64  are different from the display  22 , the touch panel  23 , and the buzzer  24  according to the first embodiment in terms of the following points. 
         [0072]    First, the touch panel  63  and the buzzer  64  are each connected to the camera-control ECU  61  instead of the equipment computer  21 . In addition, the display  62  displays various information and button images for setting the adjustment setting value TA in response to an instruction from the camera-control ECU  61 . Furthermore, the touch panel  23  accepts an input operation on the camera-control ECU  61  by the user. Still further, the buzzer  24  generates a warning sound in response to an instruction from the camera-control ECU  61 . The display  62  and the touch panel  63  are installed inside a cabin of the vehicle  30  at positions where the user can operate. For example, the display  62  and the touch panel  63  are mounted on an instrument panel of the vehicle  30 . 
         [0073]    Furthermore, the camera-control ECU  61  according to the second embodiment executes processes that are partially different from those executed by the camera-control ECU  12  according to the first embodiment. Details of the processes executed by the camera-control ECU  61  will be described in the following with reference to  FIG. 8 .  FIG. 8  is a flowchart showing the processes executed by the camera-control ECU  61  according to the second embodiment. 
         [0074]    When the camera-control ECU  61  initiates a camera control process shown in  FIG. 8 , first, the camera-control ECU  61  determines whether or not a setting-change screen has been called up (step C 1 ). Specifically, the camera-control ECU  61  displays on the display  62  a button (hereinafter, referred to as a change screen call-up button) to call up a screen for setting the adjustment setting value TA as shown in  FIG. 6 . Then, when a touch input to the change screen call-up button is detected (“Yes” at step C 1 ), the camera-control ECU  61  accepts, in the same manner as step B 8 , setting change to the adjustment setting value TA (step C 2 ). When the camera-control ECU  61  has not detected the touch input to the change screen call-up button (“No” at step C 1 ), the camera-control ECU  61  advances the process to step C 5 . While accepting a setting change for the adjustment setting value TA, the camera-control ECU  61  determines, in the same manner as the above described step B 9 , whether or not the setting has been completed (step C 3 ). Here, when the camera-control ECU  61  has not detected the touch input to the setting button E, the camera-control ECU  61  determines that the setting of the adjustment setting value TA has not been completed (“No” at step C 3 ), and waits until the touch input to the setting button E is detected (return to step C 2 ). On the other hand, when the camera-control ECU  61  detects the touch input to the setting button E, the camera-control ECU  61  determines that the setting of the adjustment setting value TA has been completed (“Yes” at step C 3 ), and stores, in a storage device of the camera-control ECU  61 , the above described numerical value accepted at step C 3  as a value of the adjustment setting value TA (step C 4 ). When the process at step C 4  is completed, the camera-control ECU  61  advances the process to step C 5 . 
         [0075]    At step C 5 , the camera-control ECU  61  determines whether or not the user has given an adjustment-start instruction (step C 5 ). Specifically, the camera-control ECU  61  displays on the display  62  a button (hereinafter, referred to as an adjustment-start button) for giving an instruction to initiate the optical axis adjustment. Then, when a touch input to the adjustment-start button is detected (“Yes” at step C 5 ), the camera-control ECU  61  initiates the optical axis adjustment. Specifically, the camera-control ECU  61  first sets, in the same manner as the above described step A 4 , the value of the exposure time T to the adjustment setting value TA (step C 6 ). Next, similar to the above described step A 5 , the camera-control ECU  61  executes the optical axis adjustment (step C 7 ). When the process at step C 7  is completed, the camera-control ECU  61  determines, in the same manner as the above described step A 6 , whether or not the optical axis adjustment has been completed properly (step C 8 ). Then, when the camera-control ECU  61  determines that the axis adjustment has been completed properly (“Yes” at step C 8 ), the camera-control ECU  61  displays on the display  62  an image (hereinafter, referred to as an adjustment-completion image) indicating that the adjustment has been completed properly (step C 9 ). After displaying the adjustment-completion image, the camera-control ECU  61  returns the process to step C 1 , and repeats the above described processes. On the other hand, when the camera-control ECU  61  determines that the axis adjustment has not been completed properly (“No” at step C 8 ), the camera-control ECU  61  executes a process to deal with an abnormality during adjustment (from step CIO to step C  12 ). 
         [0076]    First, the camera-control ECU  61  calculates the image brightness L in the same manner as the above described process at step A 8  (step C  10 ). Next, the camera-control ECU  61  informs the user about an abnormality in the adjustment in the same manner as the above described process at step B 6  (step C 11 ). Then, the camera-control ECU  61  displays on the display  62  the value of the image brightness L calculated at step C 10  (step C  12 ). When the process at step C  12  is completed, the camera-control ECU  61  returns the process to step C 1 , and repeats the above described processes. 
         [0077]    On the other hand, when the touch input to the adjustment-start button has not been detected at step C 5 , the camera-control ECU  61  conducts an image capturing process (from step C 13  to step C  14 ). Specifically, the camera-control ECU  61  automatically sets the exposure time T in the same manner as the above described step A 2  (step C  13 ). Then, the camera-control ECU  61  captures an image in the same manner as the above described step A 3  (step C 14 ). When the process at step C 14  is completed, the camera-control ECU  61  returns the process to step C 1 , and repeats the above described processes. 
         [0078]    With the above described image capturing device  40  according to the second embodiment, at the time of the optical axis adjustment, the value of the exposure time T can be set to the adjustment setting value TA without having any communications between the image capturing device  40  and the adjusting equipment  20 . Therefore, the optical axis adjustment can be executed accurately even in an environment where the adjusting equipment  20  does not exist. 
         [0079]    It should be noted that the camera-control ECU  61  according to the second embodiment may be configured so as to be communicably with the equipment computer  21  according to the first embodiment. Then, when the camera-control ECU  61  receives the adjustment setting value TA from the equipment computer  21 , the camera-control ECU  61  may execute the processes of the camera-control ECU  21  shown in  FIG. 4 . 
       INDUSTRIAL APPLICABILITY 
       [0080]    The image capturing device and the optical axis adjusting system for the image capturing device according to the present invention are respectively useful as an image capturing device and an optical axis adjusting system for the image capturing device enabling an accurate optical axis adjustment. 
       DESCRIPTION OF THE REFERENCE CHARACTERS 
       [0081]      1  optical axis adjusting system 
         [0082]      10 ,  40  image capturing device 
         [0083]      11 ,  60  on-board camera 
         [0084]      12 ,  61  camera-control ECU 
         [0085]      20  adjusting equipment 
         [0086]      21  equipment computer 
         [0087]      22 ,  62  display 
         [0088]      23 ,  63  touch panel 
         [0089]      24 ,  64  buzzer 
         [0090]      25  transport device 
         [0091]      30  vehicle 
         [0092]      50  target