JPH1137954A - Method and system for picking up image of object - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and a system for picking up the image of an object while selecting a camera optimal for the image picking up state among a plurality of cameras. SOLUTION: In order to pick up the image of a moving object 20 while switching a line sensor camera 2 or an area sensor camera 3, a clock section C, an operating signal generating section 17 and an image signal switching section 12 are selected by a switching signal from a camera switching section E depending on a selected camera. An operating clock is switched in synchronism with the preceding and following clocks so that a pulse noise is not generated and an image pickup signal or a read-out signal is outputted as an operating signal depending on a selected camera. An image signal from the camera is switched selectively and a two-dimensional image is produced from an image memory 14.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a component mounting apparatus for mounting an electronic component on a substrate by switching a plurality of cameras in accordance with the moving speed and size of the transported electronic component to image the electronic component. More particularly, the present invention relates to a method and an apparatus for imaging a recognition target object, such as an image with a required resolution and an imaging range.

[0002]

2. Description of the Related Art A line sensor camera is an effective imaging means for imaging an object moving at a constant speed, such as a product conveyed in a production facility, for inspection or the like.

FIG. 5 shows a configuration in which a moving recognition target 33 is imaged at a predetermined position by the line sensor camera 38.

[0004] A transport device is constituted by a moving head 36 attached to a ball screw 35 rotated and driven by a motor 34, and the object 33 to be recognized is moved while being held by the moving head 36. In such a transport structure,
Since the moving distance of the recognition target 33 can be known from the number of rotations of the motor 34, an encoder 37 is attached to the motor 34, an output pulse from the encoder 37 is input to the camera interface 40, and the line sensor camera 38
Is controlled.

In the camera interface 40,
A pitch counter 41 that counts output pulses from the encoder 37 outputs a counted pitch signal. The horizontal counter 43 clears the counter value to 0 by the signal from the operation start detector 44 and the pitch signal, and counts the internal clock from the clock 45,
A read signal synchronized with the pitch signal and a horizontal synchronization signal are generated. When the read signal is input to the line sensor camera 38, the line sensor camera 3
Reference numeral 8 outputs an image signal for one line. Since this read signal is output in synchronization with the moving distance of the recognition target 33, an image signal is output every time the recognition target 33 moves a predetermined distance, and the resolution of the image is kept constant.

[0006] The timing of the start of image pickup by the line sensor camera 38 is determined by the recognition target 3 located at a predetermined position.
The detection sensor 39 outputs a detection signal, and the operation start detector 44 to which the detection signal is input is used to count the value of the vertical counter 46 when the count value of the distance measurement counter 42 matches a predetermined value set in advance. To start. The vertical counter 46 obtains the number of imaged lines by counting the horizontal synchronizing signal, and stops counting when the number of lines matches a preset number of imaged lines, and only while the vertical counter 46 is operating. A vertical synchronization signal is output.

The image signal output from the line sensor camera 38 is A / D converted by an A / D converter 47 and input to an image storage device 48.
Reference numeral 8 stores an image as a two-dimensional image signal based on the horizontal synchronization signal and the vertical synchronization signal.

The line sensor camera 38 determines whether the recognition target 33 is moving or the line sensor camera 3
In contrast, in the case of an area sensor camera, the two-dimensional image is directly obtained regardless of the moving speed regardless of whether the recognition target 33 is stationary or moving. Since it is possible to take an image,
8 can be effectively used depending on the state of the recognition target 33 that is difficult to handle. FIG. 6 shows a configuration in a case where an area sensor camera is applied to the imaging state of the recognition target 33. However,
The description of the components common to the above configuration is omitted.

In FIG. 6, a horizontal counter 53 counts a clock signal from a clock 52, outputs a horizontal synchronizing signal when the count value matches a preset value, and sets the count value to 0 simultaneously with the output. The clearing operation is repeated at a constant cycle. Further, a read signal having a predetermined phase difference from the horizontal synchronization signal is output at a constant cycle. The operation of the vertical counter 54 is started by the input of the imaging start signal, and the vertical counter 54
The operation signal generator 55 generates an image signal synchronized with the readout signal at the same time as the operation starts. The operation signal generator 55 includes a counter that counts the readout signal, and uses the output of the counter to generate the imaging signal synchronized with the readout signal. By inputting this imaging signal to the area sensor camera 51, an analog image signal is output from the area sensor camera 51.

The analog image signal is supplied to an A / D converter 56.
Are converted into digital data and input to the image storage device 57. The image storage device 57 stores the image signals for one line in accordance with the horizontal synchronization signal, and stores the image signal as a two-dimensional digital image signal by repeating this while the vertical synchronization signal is being input.

[0011]

In the above-mentioned conventional configuration, when the objects to be recognized are of the same size or substantially the same size, an image can be taken by one line sensor camera. If they differ significantly,
Prepare multiple line sensor cameras with different resolutions,
It is necessary to switch according to the size of the recognition target. However, if the resolution is different, it is necessary to match the moving speed of the recognition target with a high-resolution line sensor camera, or to increase the operation clock of the high-resolution line sensor camera to match the low-resolution line sensor camera. However, when the difference in resolution is large, the difference between operation clocks is also large.In practice, the upper limit of the operation clock of the line sensor camera is almost constant, and when the size of the recognition target is significantly different, multiple line sensor cameras are switched. It is difficult to deal with. Therefore, it is conceivable to configure an imaging device by a combination of a line sensor camera and an area sensor camera.

However, since the area sensor camera and the line sensor camera have different operation structures, it is necessary to prepare an operation clock and an interface separately, and there has been a problem that the configuration of the imaging apparatus becomes complicated.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a method and an apparatus for capturing an image of an object to be recognized in which a plurality of cameras having different operation structures can be controlled by a common interface and the operation clock can be switched without malfunction due to switching impact. It is assumed that.

[0014]

According to a first aspect of the present invention, there is provided a method of imaging a recognition target object in which a plurality of cameras having different operation clocks and operation signal timings are switched to capture a moving recognition target object with different resolutions and imaging ranges. In the above, the operation clock required by the selected camera is switched at a timing synchronized with each clock before and after the clock switching, and a horizontal synchronization signal, a vertical synchronization signal, and an operation start signal based on the moving distance of the recognition object. Are generated, and are switched to an imaging signal and a readout signal corresponding to the camera selected based on these signals and output to the camera.Image signals output from a plurality of cameras are selectively switched, and the horizontal synchronization signal and the vertical A two-dimensional image signal is generated in synchronization with a synchronization signal.

According to the above imaging method, the operation clocks are switched in accordance with the operation clocks and operation signal timings of the plurality of cameras, and the horizontal synchronization signal and the vertical synchronization signal output from the common control means and the operation start. An image pickup signal and a readout signal corresponding to the camera selected based on the signal are output. When the operation clock is simply switched, erroneous operation occurs to the moving distance detection pulse or the like due to generation of pulse noise, but no malfunction occurs by switching in synchronization with the clocks before and after the switching. An image signal output from each camera is selectively switched to generate a two-dimensional image according to the horizontal synchronization signal and the vertical synchronization signal.

Therefore, even if the plurality of cameras are controlled by the common control means, no malfunction occurs, and the imaging can be switched with the simple configuration according to the resolution for recognizing the object to be recognized and the imaging range. A method can be provided.

According to a second aspect of the present invention, there is provided an image pickup apparatus for recognizing an object to be picked up at a different resolution and an image pickup range by switching a plurality of cameras having different operation clocks and operation signal timings. Imaging position detection means for detecting movement of a target object to a predetermined imaging position; and clock output means for switching and outputting an operation clock required by the selected camera at a timing synchronized with each clock cycle before and after clock switching. Horizontal timing generation means for outputting a signal required by the selected camera, vertical timing generation means for outputting a vertical synchronization signal from a start signal input from the imaging operation start detection means to a predetermined imaging period, Image storage for storing the image signal as a two-dimensional image based on a horizontal synchronization signal and a vertical synchronization signal And the step, characterized by comprising comprises a camera switching means for switching the state required by the clock output means and camera selects said horizontal timing generating means.

According to the above arrangement, when selecting a camera suitable for the resolution or the imaging range for recognizing the object to be recognized, the camera switching means switches the clock output means and the horizontal timing generation means to a state corresponding to the selected camera. Therefore, the operation clocks are switched in accordance with the operation clocks and operation signal timings of the plurality of cameras, and are selected based on the horizontal synchronization signal, the vertical synchronization signal, and the operation start signal output from the common control means. Image signals and readout signals corresponding to the cameras that have been used. When the operation clock is simply switched, erroneous operation occurs to the moving distance detection pulse or the like due to generation of pulse noise, but no malfunction occurs by switching in synchronization with the clocks before and after the switching. An image signal output from each camera is selectively switched to generate a two-dimensional image according to the horizontal synchronization signal and the vertical synchronization signal. Accordingly, there is provided an imaging apparatus capable of switching between a plurality of cameras according to a resolution and an imaging range for recognizing a recognition target object with a simple configuration without causing a malfunction even when a plurality of cameras are controlled by a common control unit. can do.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the accompanying drawings to provide an understanding of the present invention.
The embodiment described below is an example embodying the present invention, and does not limit the technical scope of the present invention.

FIG. 1 is a block diagram showing a configuration of an imaging apparatus according to an embodiment of the present invention, FIG. 2 is a block diagram showing a configuration of a horizontal counter in the apparatus, and FIG. 3 is a configuration diagram showing a clock switching structure. FIG. 4 is a timing chart of clock switching for explaining the clock switching operation.

In FIG. 1, an object 20 to be recognized is held at a moving head 21 attached to a ball screw 19 rotated and driven by a motor 18 and is conveyed at a constant speed. The device 1 is configured to be able to switch between the line sensor camera 2 and the area sensor camera 3 according to the size and type of the recognition target object 20 to capture an image.

The imaging apparatus 1 includes an imaging unit A, a control unit B,
A clock section (clock output means) C and an image processing section D
And a camera switching unit (camera switching means) E. The configuration of each unit will be described below in order.

The image pickup section A includes an image pickup camera of the line sensor camera 2 and the area sensor camera 3, an illuminating device 4 for illuminating the recognition target 20 without impairing the image pickup field of each image pickup camera, and an image pickup camera. And an operation signal generation unit (operation signal generation means) 17 that outputs an imaging signal, a readout signal, a clock signal, and an illumination lighting signal according to the operation of the line sensor camera 2 or the area sensor camera 3.

Since the phase difference between the horizontal synchronizing signal and the readout signal differs between the line sensor camera 2 and the area sensor camera 3, the operation signal generation unit 17 generates a clock by the camera switching signal (s) from the camera switching unit E. A read signal is generated when the count value reaches a predetermined value using a counter that operates with the clock output from the unit C. The count value is set in advance to a predetermined value corresponding to each of the line sensor camera 2 and the area sensor camera 3, and is switched by the camera switching signal (s). Further, the lighting time of the lighting device 4 is controlled from the input vertical synchronization signal. When the line sensor camera 2 is used, an illumination lighting signal is output while the vertical synchronization signal is being input. When the area sensor camera 3 is used, a short time (for example, a half cycle of the horizontal synchronization signal) when the vertical synchronization signal is input is used.
Only the lighting signal is output. The lighting device 4 lights up only when the lighting lighting signal is input, and illuminates the recognition target object 20.

The control unit B includes an encoder 15 for detecting the number of rotations of the motor 18 of the transport unit that transports the recognition target 20.
, A detection signal from a position detection sensor (imaging position detecting means) 16 that detects the recognition target 20 that has reached the imaging position, and a clock signal from the clock unit C. Since the period of the output signal from the encoder 15 is proportional to the moving speed of the recognition target 20, this is detected as a moving speed pulse by the pitch counter (moving distance detecting means) 5, and the pitch corresponding to a certain distance is detected. A pitch signal is output every time.

The movement distance of the recognition target 20 can be measured by counting the pitch signal by the distance measurement counter 6, and the movement distance measurement signal is input to the operation start detecting section (imaging operation start detecting means) 7. You. The operation start detecting section 7 operates the vertical counter (vertical timing generation means) 9 when the count value of the distance measurement counter 6 reaches a predetermined value from the time when the detection signal from the position detection sensor 16 is input. Since the signal is output, the vertical counter 9 starts operating and outputs a vertical synchronization signal. The pitch signal from the pitch counter 5 is also input to a horizontal counter (horizontal timing generating means) 8, and the horizontal counter 8 counts the pitch signal based on an operation clock. The horizontal counter 8 is configured as shown in FIG. 4, and when the line sensor camera 2 is used, the count value of the counter 26 is cleared using the pitch signal from the pitch counter 5 as a clear signal. On the other hand, when the area sensor camera 3 is used, the count value is cleared using the output signal of the horizontal period comparator 28 as a clear signal. The horizontal cycle comparator 28 compares the output of the counter 26 with a preset value and outputs a clear signal when they match. Thus, the horizontal counter 8 operates in synchronization with the moving distance of the recognition target object 20 when using the line sensor camera 2, and operates at a predetermined constant cycle when using the area sensor camera 3. The output signal of the horizontal period comparator 28 is input to the operation signal generator 17 of the imaging unit A as an operation signal. Further, the horizontal synchronization comparator 27
Outputs a horizontal synchronization signal by comparing the output of the counter 26 with a preset value. With this operation, the operation signal and the horizontal synchronization signal are output in a synchronized state.

The vertical counter 9 counts the horizontal synchronizing signal from the start of the operation in response to the imaging start signal, and outputs the vertical synchronizing signal to the image storage device 14 while the imaging operation is being performed. Therefore, even if the operation clock is different between the line sensor camera 2 and the area sensor camera 3, it does not affect the operation.

The clock section C switches between different operation clocks when the line sensor camera 2 is used and when the area sensor camera 3 is used, and outputs the clocks without giving an impact. The clock unit C includes an oscillator 10a for generating an operation clock CLK1 of the area sensor camera 2, and an operation clock C of the area sensor camera 3.
An oscillator 10b for generating LK2 is provided. The clock switch 11 switches and outputs the operation clock CLK1 and the operation clock CLK2. The clock switch 11 is configured as shown in FIG. 3, and the four flip-flop circuits 22 to 25 are configured as D latches, and a clock switching signal (t) output from the camera switching unit E.
The operation clock CLK1 or the operation clock CLK2 is output in accordance with the high level (H) and the low level (L).

As shown in FIG. 3, the clock CLK1 is input to the flip-flop circuits 22 and 23, the clock CLK2 is input to the flip-flop circuits 24 and 25, and the clock switching signal ( t) is input to the flip-flop circuits 22 and 24, and the output signal of the flip-flop circuit 24 is input to the flip-flop circuit 23 and the output signal of the flip-flop circuit 22 is input to the flip-flop circuit 25, and is shown in FIG. As described above, by switching between the low level and the high level of the clock switching signal (t), the clock CLK
1 or from the rising edge of the clock CLK2 to the next rising edge.
It is switched with K2 with a fixed period in between. Therefore, no pulse noise is generated by switching with a switch or the like, and no malfunction occurs in the control unit B that operates based on the pulse signal.

The image processing unit D outputs only one of the image signal from the line sensor camera 2 and the image signal from the area sensor camera 3 according to the image signal switching signal (i) output from the camera switching unit E. , An A / D converter 13 for converting an image signal, which is an analog signal, into a digital signal, and a controller B
And an image storage device 14 that stores a two-dimensional image signal using the horizontal synchronization signal and the vertical synchronization signal input from the storage device.

When the camera switching unit E switches cameras according to conditions such as the size and moving speed of the recognition target 20,
A clock switch signal (t) is output to the clock switch 11, a camera switch signal (s) is output to the operation signal generator 17, an image switch signal (i) is output to the image signal switch 12, and a clear switch signal (c) is output to the horizontal counter 8. I do. The camera switching signal (s) and the image switching signal (i) may be switching between a high-level signal and a low-level signal or an on / off signal like the clock switching signal (t) described above.

The respective operations of the image pickup apparatus 1 having the above-described configuration when an image is picked up by the line sensor camera 2 and the area sensor camera 3 will be described in order.

[Imaging Operation by Line Sensor Camera 2] (1) An output signal from the encoder 15 is counted by the pitch counter 5, and a pitch signal is generated for each count value corresponding to the recognition target 20 moving a fixed distance. Output. The pitch signal interval is the resolution in the moving direction of the recognition target 20 by the line sensor camera 2.

(2) The pitch signal is counted by the distance measurement counter 6 to measure the moving distance of the recognition target 20.

(3) When the position detection sensor 16 detects that the recognition target 20 has moved to the image pickup position, and a detection signal is input to the operation start detection unit 7, the operation start detection unit 7
Starts the vertical counter 9 and outputs a vertical synchronization signal.

(4) The vertical synchronizing signal is supplied to the operation signal generator 17.
The lighting device 4 is turned on by a lighting lighting signal output from the operation signal generating unit 17 and illuminates the recognition target 20 that has moved to a predetermined position.

(5) After the count value of the horizontal counter 8 is cleared by the pitch signal from the pitch counter 5,
When the count of the operation clock is started and the preset value matches the count value, an operation start signal and a horizontal synchronization signal are output. With this operation, the analog image signal output from the line sensor camera 2 and the horizontal synchronizing signal always keep a constant phase difference.

(6) The operation signal generator 17 inputs the readout signal generated with a certain phase difference from the operation start signal by the operation clock to the line sensor camera 2.

(7) The line sensor camera 2 outputs a one-line analog image signal in accordance with the readout signal and the operation clock.

(8) The image signal switching unit 12 outputs the input analog image signal to the A / D conversion unit 13, and the A / D conversion unit 13 converts the analog image signal into a digital image signal and converts the analog image signal into a digital image signal. Input to 14.

(9) The image storage device 14 stores a digital image signal for one line in accordance with the horizontal synchronizing signal, and repeats this operation while the vertical synchronizing signal is being input, thereby storing a two-dimensional image signal.

(10) When the count value of the vertical counter 9 matches the preset number of imaging lines, the output of the vertical synchronizing signal is stopped, and the imaging operation ends.

When switching from the imaging by the line sensor camera 2 to the imaging by the area sensor camera 3 as described above,
Alternatively, when switching to the opposite state, the camera switching unit E causes the clock unit C, the operation signal generation unit 17,
The setting of the image signal switching unit 12 and the horizontal counter 8 is switched to the imaging state of the area sensor camera 3 or the line sensor camera 2.

[Imaging operation by the area sensor camera 3] (1) The output signal from the encoder 15 is counted by the pitch counter 5, and the pitch signal is generated for each count value corresponding to the movement of the recognition target 20 by a fixed distance. Output.

(2) The pitch signal is counted by the distance measuring counter 6 to measure the moving distance of the recognition target 20.

(3) When the position detection sensor 16 detects that the recognition target 20 has moved to the image pickup position, and a detection signal is input to the operation start detection unit 7, the operation start detection unit 7
Starts the vertical counter 9 and outputs a vertical synchronization signal.

(4) The vertical synchronizing signal is supplied to the operation signal generator 17.
The illumination device 4 is lit for one horizontal synchronization period by the illumination lighting signal output from the operation signal generation unit 17 and illuminates the recognition target 20 that has moved to a predetermined position.

(5) After the count value of the horizontal counter 8 is cleared by the pitch signal from the pitch counter 5,
When the count of the operation clock is started and the preset value matches the count value, an operation start signal and a horizontal synchronization signal are output, and the count value becomes a value corresponding to one horizontal synchronization period. When the output of the horizontal counter 8 itself is 0,
To clear. By this operation, the analog image signal output from the line sensor camera 2 and the horizontal synchronizing signal always keep a constant phase difference, and the period during which one line of image signal is read is kept constant.

(6) The operation signal generator 17 inputs the read signal generated with a further constant phase difference from the operation start signal by the operation clock to the area sensor camera 3.

(7) The image signal switching unit 12 converts the analog image signal output from the area sensor camera 3 into the A / D converter 1
The A / D converter 13 converts the analog image signal into a digital image signal and inputs the digital image signal to the image storage device 14.

(8) The image storage device 14 stores a digital image signal for one line according to the horizontal synchronization signal, and stores a two-dimensional image signal by repeating this operation while the vertical synchronization signal is being input.

(9) When the count value of the vertical counter 9 matches the preset number of imaging lines, the output of the vertical synchronizing signal is stopped, and the imaging operation ends.

When the image of the recognition target 20 is continuously taken by the imaging apparatus 1 described above, the position of the recognition target 2 by the position detection sensor 16 depends on the size of the recognition target 20.
The distance from the detection of 0 to the start of imaging can be obtained in advance, and the distance can be given to the operation start detection unit 7 to implement this.

The operation start detecting section 7 includes a position detecting sensor 16.
From the distance measurement counter 6
Starts the operation of the vertical counter 9 when the counted distance matches the preset distance.

[0055]

As described above, according to the first aspect of the present invention, the operation clocks are switched in accordance with the operation clocks and operation signal timings of a plurality of cameras.
An image pickup signal or a readout signal corresponding to a camera selected based on the horizontal synchronization signal, the vertical synchronization signal, and the operation start signal output from the common control unit is output. When the operation clock is simply switched, erroneous operation occurs to the moving distance detection pulse or the like due to generation of pulse noise, but no malfunction occurs by switching in synchronization with the clocks before and after the switching. An image signal output from each camera is selectively switched to generate a two-dimensional image according to the horizontal synchronization signal and the vertical synchronization signal. Therefore, there is provided an imaging method capable of switching between a plurality of cameras according to a resolution and an imaging range for recognizing a recognition target object with a simple configuration without causing a malfunction even when a plurality of cameras are controlled by a common control unit. can do.

Further, according to the second aspect of the present invention, when selecting a camera suitable for the resolution and the imaging range for recognizing the object to be recognized, the camera switching means switches the clock output means and the image signal switching means to the selected camera. Since the state can be switched to the corresponding state, the operation clocks are switched in accordance with the operation clocks and operation signal timings of the plurality of cameras, and the horizontal synchronization signal, the vertical synchronization signal, the operation start signal, and the horizontal synchronization signal output from the common control unit are changed. Can output an image pickup signal or a readout signal corresponding to the camera selected based on the image data. When the operation clock is simply switched, erroneous operation occurs to the moving distance detection pulse or the like due to generation of pulse noise, but no malfunction occurs by switching in synchronization with the clocks before and after the switching. An image signal output from each camera is selectively switched to generate a two-dimensional image according to the horizontal synchronization signal and the vertical synchronization signal. Therefore,
Provided is an imaging apparatus which can switch between a plurality of cameras in accordance with a resolution and an imaging range for recognizing a recognition target object with a simple configuration without causing a malfunction even when a plurality of cameras are controlled by a common control unit. Can be.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of an imaging device according to an embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of a horizontal counter in the device.

FIG. 3 is a block diagram showing a configuration of a clock switch in the device.

FIG. 4 is a timing chart illustrating the operation of the clock switching device.

FIG. 5 is a block diagram showing a configuration of an imaging device using a line sensor camera according to a conventional example.

FIG. 6 is a block diagram showing a configuration of an imaging device using an area sensor camera according to a conventional example.

[Explanation of symbols]

 Reference Signs List 1 imaging device 2 line sensor camera 3 area sensor camera 5 pitch counter (moving distance detecting means) 7 operation start detecting section (imaging operation start detecting means) 8 horizontal counter (horizontal timing generating means) 9 vertical counter (vertical timing generating means) REFERENCE SIGNS LIST 11 clock switch 12 image signal switching unit (image signal switching unit) 14 image storage device (image storage unit) 15 encoder (moving distance detection unit) 16 position detection sensor (imaging position detection unit) 17 operation signal generation unit (operation signal) Generating means) A imaging unit B control unit C clock unit (clock output unit) D image processing unit E camera switching unit (camera switching unit)

Claims (2)

[Claims] 1. A method for imaging a recognition target in which a plurality of cameras having different operation clocks and operation signal timings are switched and a moving recognition target is captured with different resolutions and imaging ranges is required by the selected camera. The operation clock is switched at a timing synchronized with each clock before and after the clock switching, and a horizontal synchronization signal, a vertical synchronization signal, and an operation start signal are generated based on the moving distance of the recognition target, and based on these signals, Outputting an imaging signal and a readout signal corresponding to the selected camera to the camera, and synchronizing image signals output from the plurality of cameras with the horizontal synchronization signal and the vertical synchronization signal to generate a two-dimensional image signal. The imaging method of the recognition target object to be described. 2. An imaging device for a recognition target, which switches between a plurality of cameras having different operation clocks and operation signal timings and captures a moving recognition target with different resolutions and imaging ranges. Imaging position detecting means for detecting movement of the selected camera, clock output means for switching and outputting an operation clock required by the selected camera at a timing synchronized with each clock cycle before and after clock switching, and Horizontal timing generation means for outputting a required operation start signal, vertical timing generation means for outputting a vertical synchronization signal from a signal input from the imaging operation start detection means to a predetermined imaging period, and the horizontal synchronization signal and the vertical synchronization Image storage means for storing the image signal as a two-dimensional image based on the signal; Imaging device of the recognition target object, characterized in that the output means and camera selects said horizontal timing generating means is comprises a camera switching means for switching to a state in need.