JPH0614253A - Ccd television camera with outside trigger function - Google Patents

Abstract

PURPOSE:To easily execute a lens diaphragm and a focus adjustment or the like without necessitating the operation of a changeover switch or the like, in a CCD television camera with an outside trigger function which discharges or stores a charge by inputting a trigger signal from an outside. CONSTITUTION:A driving circuit 4 outputs a signal for outputting a signal charge stored on the pixel of a CCD image pickup element 1. An electronic shutter circuit 5 outputs a signal for discharging the surplus charge stored on the pixel for a period of time except a shutter time. And also, a synchronizing signal generating circuit 3, driving circuit 4, and electronic shutter circuit 5 input the trigger signal outputted from the outside, and switch the operation according to the trigger signal state.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a CCD television camera with an external trigger function for discharging and accumulating charges by inputting an external trigger signal.

[0002]

2. Description of the Related Art In an industrial television camera installed in a factory inspection line or the like and used for automatic visual inspection of products, a sensor installed separately to project a moving subject. The output of the above is used as a trigger signal, and the function of storing and outputting the signal charge by inputting the trigger signal is called an external trigger function or a random shutter function. In the following description, the above-mentioned functions will be collectively described under the name of an external trigger function.

A conventional CCD television camera with an external trigger function is shown in FIG. In FIG. 3, the CCD image pickup device 1 converts an optical signal into an electric signal and outputs the electric signal to the video signal processing circuit 2. The video signal processing circuit 2 performs video signal processing such as sample hold, clamp, amplification, reset noise removal and γ processing on the input signal, and further adds a sync signal output from the sync signal generation circuit 3 Output as a television signal. The drive circuit 4 outputs transfer signals such as a reset signal, a horizontal transfer signal, and a vertical transfer signal to the CCD image pickup device 1. Further, the drive circuit 4 superimposes a charge read signal for transferring the signal charges accumulated on the pixels of the CCD image pickup device 1 to the vertical transfer register and outputs the signal. The electronic shutter circuit 5 accumulates electric charges on the pixels at a time corresponding to the shutter time, and outputs to the CCD image pickup device 1 a charge sweep signal for discharging the excess electric charges to the outside of the CCD image pickup device 1. It is necessary that the transfer signal, the charge sweep signal, and the like have the same phase as the synchronization signal. Therefore, the synchronizing signals such as the HD signal and the VD signal at the output of the synchronizing signal generating circuit 3 are input to the drive circuit 4 and the electronic shutter circuit 5. The mode setting switch 6 switches between a normal electronic shutter operation and an external trigger operation. The trigger signal input from the outside is when the operation of the camera is the external trigger operation by the mode setting switch 6.
It is input to the synchronizing signal generating circuit 3, the driving circuit 4, and the electronic shutter circuit 5, and an external trigger operation is performed according to the rising of the trigger signal.

Next, details of the operation of the conventional CCD television camera with an external trigger function shown in FIG. 3 will be described. In FIG. 3, when the mode setting switch 6 is on the normal operation side, the normal electronic shutter operation is performed to sweep out, store and read out the electric charges once for each field. First, the above-mentioned normal operation state is set, and the lens diaphragm, focus adjustment, and camera gain setting are performed. When these camera side preparations are completed, the mode setting switch 6 is switched to the external trigger side. In this state, the electronic shutter circuit 5 continuously outputs the charge sweep signal at every predetermined time so that the charge is not accumulated in the CCD image pickup device 1. Further, the drive circuit 4 stops the output of the charge read signal superimposed on the vertical transfer signal. By the operation of these electronic shutter circuit 5 and drive circuit 4,
A charge does not exist on the charge transfer register of the CCD image pickup device 1, and a trigger signal standby state is created in which the charge stored on the pixel is also discharged at every predetermined time. In this trigger signal standby state, there is no output from the video signal processing circuit 2, that is, no video signal output from the camera.

In this state, when the trigger signal output from the external sensor or the like becomes low, the electronic shutter circuit 5 is activated at the same time when the trigger signal rises.
Outputs only one charge sweep signal, and thereafter stops the output of the charge sweep signal. With these, CC
Signal charges start to be accumulated on the pixels of the D image pickup device 1 at the same time when the trigger signal rises. Then, when the preset accumulation time, that is, the shutter time is reached, the charge read signal is output from the drive circuit 4, and the CC
A signal charge is output from the D image sensor 1. The synchronization signal generation circuit 3 resets the synchronization signal by inputting the trigger signal and synchronizes with the signal output from the CCD image pickup device 1. The output of the CCD image pickup device 1 is output as a television signal through the video signal processing circuit 2.

[0006]

However, in the above-mentioned conventional CCD television camera with an external trigger function, when the mode setting switch 6 is set to the external trigger side, the television signal is transmitted from the video signal processing circuit 2. Since it does not output, it is impossible to adjust the lens diaphragm and focus. Therefore, it is necessary to set the mode setting switch 6 to the normal operation side in advance, adjust the lens and the camera, and then switch the mode setting switch 6 to the trigger side. Therefore, in the above-described conventional CCD TV camera with an external trigger function, the mode setting switch 6 is switched to the normal operation side and readjusted every time the illumination condition of the subject is changed and the adjustment of the lens aperture is required. There is a problem that it must be. Since the mode setting switch 6 is often provided inside the camera in order to reduce the size of the camera body, there is a problem in that the operability is deteriorated especially when an image processing device or the like is incorporated.

The present invention has been made in view of the above problems, and has an external trigger function C for discharging and accumulating charges by inputting a trigger signal from the outside.
It is an object of the present invention to provide a CD television camera with an external trigger function, which can easily perform adjustment of a lens diaphragm and a focus without requiring an operation of a changeover switch or the like.

[0008]

A CCD television camera with an external trigger function according to the present invention is a CCD image pickup device for converting an optical signal into an electric signal, and an electronic shutter circuit for discharging charges on pixels of the CCD image pickup device. And a drive circuit for reading out electric charges accumulated on the pixels of the CCD image pickup device at a preset shutter time, and video signal processing for inputting the electric charges read out by the driving circuit and outputting as a television signal. A circuit, and a synchronization signal generation circuit for outputting a synchronization signal for operating the electronic shutter circuit, the drive circuit, the video signal processing circuit and the like in synchronization, and at least the electronic shutter circuit and the drive circuit And the synchronization signal generating circuit are capable of switching the operation according to the state of the trigger signal input from the outside at an arbitrary timing. The features. In the CCD television camera with an external trigger function according to the present invention, when the trigger signal input from the outside is in the first state, sweeping away charges on the pixels of the CCD image pickup device, accumulating charges, and discharging charges. When the normal electronic shutter operation for reading is performed and the trigger signal input from the outside is in the second state, the video signal processing circuit is synchronized with the timing when the trigger signal input from the outside becomes the third state. It is preferable to output the video signal from the.

[0009]

In the CCD television camera with the external trigger function according to the present invention, the synchronizing signal generating circuit and the driving circuit are provided in the CCD television camera with the external trigger function for discharging and accumulating charges by inputting the trigger signal from the outside. Then, the electronic shutter circuit inputs a trigger signal output from the outside and switches its operation depending on the state of the trigger signal. When the trigger signal input from the outside is in the first state, the C
A normal electronic shutter operation for sweeping out charges, accumulating charges and reading charges on the pixels of the CD image pickup device is performed. During this operation, the lens diaphragm, focus adjustment, and camera gain setting can be performed. On the other hand, when the trigger signal input from the outside is in the second state, the video signal is output from the video signal processing circuit in synchronization with the timing when the trigger signal input from the outside becomes the third state. As a result, the CCD television camera with the external trigger function according to the present invention can easily execute the diaphragm and focus adjustment of the lens without changing the setting of the camera body.

[0010]

Embodiments of the present invention will now be described with reference to the accompanying drawings.

FIG. 1 is a circuit diagram showing a CCD television camera with an external trigger function according to an embodiment of the present invention. In FIG. 1, the same components as those of the conventional CCD television camera with an external trigger function shown in FIG. 3 are designated by the same reference numerals, and detailed description thereof will be omitted. In the CCD television camera with an external trigger function according to the embodiment of the present invention shown in FIG. 1, the conventional C with an external trigger function shown in FIG.
A component different from the CD television camera is a portion in which the mode setting switch 6 is deleted. The CCD image pickup device 1 is an interline transfer type CCD image pickup device or the like.

Next, the operation of the CCD television camera with the external trigger function according to the present embodiment constructed as described above will be described. FIG. 2 is a timing chart showing the operation of each part in the CCD television camera with the external trigger function shown in FIG. When the trigger signal a shown in FIG. 2 is low, a normal electronic shutter operation for sweeping out, accumulating, and reading out charges in the CCD image pickup device 1 is performed once for each field. Focus adjustment and camera gain setting can be performed. When these preparations on the camera side are completed, the trigger signal a is externally switched to high. When the CCD television camera with the external trigger function detects that the trigger signal a becomes high, the electronic shutter circuit 3
Outputs the charge sweep-out signal b continuously every predetermined time so that the charge is not accumulated in the CCD image pickup device 1. Further, the drive circuit 4 stops the output of the charge read signal superimposed on the vertical transfer signal. Due to the operations of the electronic shutter circuit 5 and the drive circuit 4, the charge does not exist on the charge transfer register of the CCD image pickup device 1 and the charge accumulated on the pixel is discharged at a predetermined time. Is created. In this trigger signal standby state, there is no output from the video signal processing circuit 2, that is, no video signal output from the camera.

Next, when the trigger signal a becomes low, the electronic shutter circuit 5 outputs only one charge sweep signal at the same time when the trigger signal a falls, and thereafter stops the output of the charge sweep signal. . As a result, signal charges start to be accumulated on the pixels of the CCD image pickup device 1 at the same time when the trigger signal a falls. Then, when the preset accumulation time, that is, the shutter time e is reached, the charge read signal c is output from the drive circuit 4 and the signal charge is output from the CCD image pickup device 1.
At this time, a predetermined reference period is set for the period when the trigger signal a is low, and when the period when the trigger signal a is low is shorter than the reference period, the trigger operation continues. If it is longer than the reference period, the normal operation state is restored. Sync signal generation circuit 3
Is reset by inputting the trigger signal a and is synchronized with the signal output from the CCD image pickup device 1. The output of the CCD image pickup device 1 is output as a television signal d via the video signal processing circuit 2.

With these operations, the CCD television camera with the external trigger function according to the present embodiment can easily perform the adjustment of the lens diaphragm and the focus without the operation of the changeover switch or the like.

[0015]

As described above, according to the CCD television camera with the external trigger function according to the present invention, the normal electronic shutter operation and the trigger operation can be switched by detecting the state of the trigger signal input from the outside. Therefore, even if the CCD TV camera with the external trigger function is installed in the image processing device, by inputting a predetermined trigger signal, the aperture and focus of the lens can be adjusted without changing the setting of the camera body. It can be easily implemented. Further, the CCD television camera with an external trigger function according to the present invention does not require a switching function such as a mode setting switch for switching between a normal electronic shutter operation and a trigger operation, so that the camera body can be downsized. it can.

[Brief description of drawings]

FIG. 1 is a C with an external trigger function according to an embodiment of the present invention.
It is a block diagram which shows a CD television camera.

FIG. 2 is a timing chart showing the operation of each part in the CCD television camera with the external trigger function shown in FIG.

FIG. 3 is a block diagram showing an example of a conventional CCD television camera with an external trigger function.

[Explanation of symbols]

 1; CCD image pickup device 2; video signal processing circuit 3; synchronization signal generation circuit 4; drive circuit 5; electronic shutter circuit

Claims (2)

[Claims] 1. A CCD image pickup device for converting an optical signal into an electric signal, an electronic shutter circuit for discharging charges on pixels of the CCD image pickup device, and a pixel of the CCD image pickup device at a preset shutter time. A drive circuit for reading the charges accumulated above, a video signal processing circuit for inputting the charges read by the drive circuit and outputting as a television signal, the electronic shutter circuit, the drive circuit, and the video signal processing circuit And a synchronizing signal generating circuit that outputs a synchronizing signal that operates in synchronization with each other, and at least the electronic shutter circuit, the driving circuit, and the synchronizing signal generating circuit are externally input at arbitrary timings. CCD TV camera with an external trigger function, which switches its operation according to the state of the trigger signal. 2. When the trigger signal input from the outside is in the first state, a normal electronic shutter operation for sweeping away charges on the pixels of the CCD image pickup device, accumulating charges and reading out charges is performed. When the trigger signal input from the outside is in the second state, the video signal is output from the video signal processing circuit in synchronization with the timing when the trigger signal input from the outside becomes the third state. A CCD television camera with an external trigger function according to claim 1.