JPH05145806A - View finder input changeover device for video camera - Google Patents

Abstract

PURPOSE:To reduce number of input selector switches, to facilitate the operation and to prevent mis-operation of a selector switch in the view finder input changeover device for the video camera. CONSTITUTION:When an external video signal is inputted from an external VTR signal input terminal 7, a selector switch 4 is closed to switch a changeover switch 3 to the position of an external video signal application terminal 3b. When a video signal is inputted from the input terminal 7, it is detected by a synchronizing separator circuit 8 and a level detection circuit 9 and a changeover switch 5 connects the input terminal 7 and the external video signal application terminal 3b of the changeover switch 3. Then the external video signal from the input terminal 7 is fed to a view finder section 1 through the changeover switches 5, 3. Thus, number of input selector switches is reduced to be only one and the operation is facilitated and mis-operation of the selector switch is prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a viewfinder input switching device for switching a video signal displayed on a viewfinder of a video camera.

[0002]

2. Description of the Related Art There is a system for selecting video signals from a plurality of video cameras and transmitting the selected video signals to, for example, a television broadcasting station.

FIG. 3 is a schematic diagram of the above system. In the figure, 11a, 11b and 11c are video cameras, and 13a, 13b and 13c are camera control units (CCU). A reference signal Ss is supplied to these camera control units 13a, 13b, 13c in synchronization with each other. Then, the video signal from the video camera 11a is supplied to the input terminal 14a of the switcher 14 via the CCU 13a.
Video signals from the video cameras 11b and 11c are supplied to the input terminals 14b and 14c of the switcher 14 via the CCUs 13b and 13c, respectively. By the switcher 14, the video cameras 11a, 11b, 11c
One of the video signals from is selected. Then, the selected video signal is transmitted to, for example, a broadcasting station. Also, the selected video signal Sr is CCU1
3a, 13b, 13c are supplied to the video cameras 11a, 11b, 11c by a cameraman, if selected by a switch provided on the video cameras 11a, 11b, 11c. It can be monitored by the built-in viewfinder section.

Video tape recorders 12a, 12b, 12c are video tape recorders or camera-integrated video tape recorders. If selected by a switch provided in the video cameras 11a, 11b, 11c, the video tape recorder 12 is shown.
The video signals from a, 12b, and 12c can be observed by the viewfinder section.

FIG. 4 is a schematic block diagram of a viewfinder input switching device for switching a video signal supplied to the viewfinder section 1 in a video camera.

In the figure, 2 is an image pickup section and a signal processing section of a video camera, 3 is a changeover switch, and this changeover switch 3 is usually located on one input terminal 3a side.
Then, the video signal from the image pickup section and the signal processing section 2 is supplied to the viewfinder section 1 via the input terminal 3a of the changeover switch 3. Reference numeral 6 denotes a return video signal input terminal, to which the return video signal (for example, the selected video signal Sr described above) from the CCU 13a, 13b, or 13c is supplied. 7 is an external VT
It is an R signal input terminal, and the VTR 12 is connected to this input terminal 7.
The video signal from a, 12b, or 12c is supplied. Further, 5 is a changeover switch, one input terminal 5a of the changeover switch 5 is connected to the input terminal 6, and the other input terminal 5b is connected to the input terminal 7. The changeover switch 5 is normally on the side of one input terminal 5a, and the input terminal 6 is connected to the other input terminal 3b of the changeover switch 3 via the changeover switch 5.

Reference numeral 15 is an external VTR signal selection switch, 16
Is a return video signal selection switch. When the return video signal selection switch 16 is turned on, a signal indicating this is supplied to the changeover switch 3 via the OR circuit 17. Then, the changeover switch 3 causes the other input terminal 3
The video signal is supplied to the input terminal 6 on the b side, and is supplied to the viewfinder section 1 via the changeover switches 5 and 3. When the selection switch 15 is turned on, a signal indicating this is supplied to the changeover switch 5 and is also supplied to the changeover switch 3 via the OR circuit 17. Then, the changeover switch 3 becomes the input terminal 3b side, and
The changeover switch 5 is on the side of the input terminal 5b. Then, the video signal supplied to the input terminal 7 is transferred to the changeover switches 5 and 3
Is supplied to the viewfinder section 1 via.

[0008]

However, in the above-mentioned conventional viewfinder input switching device, there are two selection switches for selecting the external input signal, the external VTR signal selection switch 15 and the return video signal selection switch 16. Since the switch is present, not only the operation becomes complicated but also the unintended selection switch 15 or 16 is mistaken.
There was a possibility to turn on.

[0009]

According to the invention of claim 1, in order to solve the above-mentioned problems, a video signal from the image pickup section of the video camera and a video signal from the outside of the video camera are supplied. And a first changeover switch for supplying the video signal selected from the above two types to the viewfinder section of the video camera, and the first changeover switch from the video signal supply side terminal from the image pickup section from the outside. To a video signal supply side terminal for selecting an external video signal input, a first input terminal and a second input terminal for inputting a video signal from the outside of the video camera, and a video signal Sync signal detecting means for detecting a sync signal, the sync signal detecting means detecting a video signal supplied from the second input terminal and outputting a detection signal; When the detection signal is not output from the stage, the first input terminal is connected to the external video signal supply side terminal of the first changeover switch, and when the detection signal is output, the second input terminal is connected. A second changeover switch connected to the external video signal supply side terminal of the first changeover switch.

According to the second aspect of the invention, in order to solve the above problems, a video signal from the video section of the video camera and a video signal from the outside of the video camera are supplied, and the above-mentioned 2 A changeover switch for supplying a video signal selected from the types to the viewfinder section of the video camera, and the changeover switch for switching from the video signal supply side terminal from the image pickup section to the external video signal supply side terminal,
A selection switch for selecting the input of the external video signal, an input terminal for inputting the video signal from the outside of the video camera, and a jack into which a plug for outputting the external video signal is inserted and is connected to the input terminal. Connected to the external video signal supply side terminal of the changeover switch and the plug is not inserted in the jack.
A second contact piece that contacts the plug and separates from the first connection piece in contact with the insertion of the plug into the jack
And a jack having a connecting piece of.

[0011]

According to the first aspect of the invention, when the external video signal is input from the second input terminal, the selection switch is turned on to switch the first changeover switch to the external video signal supply side terminal. When a video signal is input from the second input terminal, this is detected by the synchronization signal detecting means, and the second changeover switch connects the second input terminal and the external video signal supply side terminal of the first changeover switch. To do. Then, the external video signal from the second input terminal is supplied to the viewfinder section via the second changeover switch and the first changeover switch.

According to the second aspect of the invention, when the external video signal is input from the jack, the changeover switch is switched to the external video signal supply side terminal when the selection switch is turned on. When the plug that outputs the external video signal is inserted into the jack, the first connection piece and the second connection piece are separated, and the plug and the second connection piece are connected. Then, the external video signal from the jack is supplied to the viewfinder section via the changeover switch.

[0013]

FIG. 1 is a schematic configuration diagram of an embodiment of the present invention, in which components equivalent to those in FIG. 4 are designated by like reference characters.

In FIG. 1, 8 is a sync separation circuit,
The sync separation circuit 8 separates the sync signal from the video signal supplied to the input terminal 7. 9 is a level detection circuit,
The level detection circuit 9 detects the level of the signal supplied from the sync separation circuit 8. Then, it is determined whether or not the level of the detected signal is equal to or higher than a predetermined value, and if the level is equal to or higher than the predetermined value, a changeover signal is supplied to the changeover switch 5.

Reference numeral 4 is an external input selection switch,
It is turned on when an external video signal is desired to be input from the input terminal 6 or 7.

Normally, the changeover switch 3 is located on the side of the one input terminal 3a, and the video signal from the image pickup section of the video camera and the signal recording section 2 is changed over.
Is supplied to the viewfinder section 1 via.

When the external video signal from the return video signal input terminal 6 is desired to be input, when the selection switch 4 is turned on, the changeover switch 3 changes from one input terminal 3a side to the other input terminal 3b side. Since the changeover switch 5 is normally located on the side of the one input terminal 5a,
The external video signal from the return video signal input terminal 6 is supplied to the viewfinder section 1 through the changeover switches 5 and 3.

Even when it is desired to input an external video signal from the external VTR signal input terminal 7, the external input selection switch is turned on and the changeover switch 3 is set to the other input terminal 3b side. When the external video signal is supplied from the input terminal 7, the sync signal is separated by the sync separation circuit 8. Then, the level detection circuit 9 determines whether or not the level of the synchronization signal is equal to or higher than a predetermined level. When the video signal is supplied to the input terminal 7, the level of the synchronizing signal is equal to or higher than the predetermined level, and therefore the level detection circuit 9 supplies the changeover signal to the changeover switch 5. Then, the changeover switch 5
The input terminal 5a side is switched to the other input terminal 5b side. Then, the external video signal from the input terminal 7 is passed through the changeover switches 5 and 3 to the viewfinder section 1
Is supplied to.

As described above, according to the embodiment of the present invention, the changeover switch 5 is normally on the return video signal input terminal 6 side, and the video signal is input to the external VTR signal input terminal 7. By the sync separation circuit 8 and the level detection circuit 9, the changeover switch 5 automatically changes to the external V
It becomes the TR signal input terminal 7 side. Therefore, conventionally, two input selection switches were required for the two external input terminals 6 and 7, but in the above embodiment, only one input selection switch 4 is required, and the operation becomes easy. An erroneous operation due to the presence of two selection switches is prevented.

FIG. 2 is a schematic block diagram of another embodiment of the present invention, in which components equivalent to those in FIG. 1 are designated by the same reference numerals.

In FIG. 2, reference numeral 10 denotes an external VTR signal input jack, and this input jack 10 has an input terminal 6
And a second terminal 10a connected to the other input terminal 3b of the changeover switch 3. Then, the first connecting piece is attached to the first terminal 10b, and the second connecting piece 1 is attached to the second terminal 10a.
0c is attached. These first connecting piece and second
The connection pieces of (1) are normally in contact with each other (in a state where no plug is inserted in the input jack 10).

When an external video signal from the return video signal input terminal 6 is desired to be input, when the selection switch 4 is turned on, the changeover switch 3 changes from one input terminal 3a side to the other input terminal 3b side. The external video signal from the input terminal 6 is connected to the terminal 10b → the connecting piece 10d → the connecting piece 1
It is supplied to the viewfinder section 1 through 0c → terminal 10a → changeover switch 3.

When it is desired to input an external video signal from the external VTR signal input jack 10, the external input selection switch is turned on and the changeover switch 3 is set to the other input terminal 3b side. When an output plug (not shown) that outputs an external VTR signal is inserted into the input jack 10, the output plug presses the second connection piece 10c, and the second connection piece 10c and the first connection. The piece 10d is separated. Then, the external video signal from the output plug is supplied to the viewfinder section 1 through the second connection piece-> the second terminal 10a-> the changeover switch 3.

As described above, according to another embodiment of the present invention, the return video signal input terminal 6 is normally connected to the other input terminal 3b of the changeover switch 3 via the input jack 10. .. When the output plug of the external video signal is inserted into the input jack 10, the input terminal 6 is separated from the other input terminal 3b of the changeover switch 3, and the output plug is connected to the other input terminal 3b. Therefore, according to the example of FIG. 2, as in the example of FIG. 1, only one input selection switch 4 is required, the operation is facilitated, and erroneous operation due to the two selection switches is prevented.

[0025]

As described above, according to the first aspect of the invention, the video signal from the image pickup section of the video camera and the video signal from the outside of the video camera are supplied, and
A first changeover switch for supplying a video signal selected from the types to the viewfinder section of the video camera;
In order to switch the first changeover switch from the video signal supply side terminal from the image pickup section to the external video signal supply side terminal and input the external video signal to the selection switch and the video signal from the outside of the video camera. A first input terminal and a second input terminal, and a sync signal detecting means for detecting a sync signal of the video signal, wherein the sync signal detecting means detects that the video signal is supplied from the second input terminal. When the detection signal is not output from the synchronization signal detecting means for outputting the signal, the first input terminal is connected to the external video signal supply side terminal of the first changeover switch, and the detection signal is Since the second input switch is connected to the external video signal supply side terminal of the first changeover switch when outputting, the second changeover switch is configured. Can be one to reduce the operation is facilitated, thereby preventing erroneous operation by the selection switch is two.

According to the second aspect of the invention, the video signal from the image pickup section of the video camera and the video signal from the outside of the video camera are supplied, and the video selected from the above two types. A selector switch for supplying a signal to the viewfinder section of the video camera, and a selector switch for selecting the input of the external video signal by switching the selector switch from the video signal supply side terminal from the image pickup section to the external video signal supply side terminal A switch, an input terminal for inputting a video signal from the outside of the video camera, a jack into which a plug for outputting an external video signal is inserted, and a first connecting piece connected to the input terminal It is connected to the external video signal supply side terminal of the changeover switch, and when the plug is not inserted in the jack, it contacts the first connection piece,
The jack having the first connecting piece and the second connecting piece which is separated from the first connecting piece and is in contact with the plug in association with the insertion of the plug into the jack.
As with the inventions related to
Therefore, the operation becomes easy, and the erroneous operation due to the two selection switches is prevented.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of an embodiment of the present invention.

FIG. 2 is a schematic configuration diagram of another embodiment of the present invention.

FIG. 3 is a schematic diagram of a plurality of video camera systems.

FIG. 4 is a schematic view of a viewfinder input switching device of a conventional video camera.

[Explanation of symbols]

1 ... Viewfinder section, 2 ... Imaging section and signal processing section,
3, 5 ... Changeover switch, 4 ... External input selection switch, 6
... Return video signal input terminal, 7 ... External VTR signal input terminal, 8 ... Synchronous separation circuit, 9 ... Level detection circuit, 10
... input jack, 10c ... second connection piece, 10d ... first
Connection piece.

Claims (2)

[Claims] 1. A video signal from an image pickup section of a video camera and a video signal from the outside of the video camera are supplied, and a video signal selected from the two types is sent to a viewfinder section of the video camera. A first changeover switch for supplying, a selection switch for changing over the first changeover switch from a video signal supply side terminal from the image pickup section to a video signal supply side terminal from the outside, and selecting an input of an external video signal; A first input terminal and a second input terminal for inputting a video signal from the outside of the video camera, and a sync signal detecting means for detecting a sync signal of the video signal, the video signal being supplied from the second input terminal. Is detected and outputs a detection signal, and when the detection signal is not output from the synchronization signal detection means, the first input terminal is turned off. A second changeover switch connected to the external video signal supply side terminal of the switch and connecting the second input terminal to the external video signal supply side terminal of the first changeover switch when the detection signal is output. And a viewfinder input switching device for a video camera. 2. A video signal from an image pickup section of the video camera and a video signal from the outside of the video camera are supplied, and a video signal selected from the two types is sent to a viewfinder section of the video camera. A changeover switch for supplying, a selection switch for changing over the changeover switch from the image signal supply side terminal from the image pickup section to the external image signal supply side terminal, and selecting the input of the external image signal, and the image from the outside of the video camera. An input terminal for inputting a signal, a jack into which a plug for outputting an external video signal is inserted, the first connecting piece connected to the input terminal, and an external video signal supply side terminal of a changeover switch If the plug is not inserted into the jack,
A second contact piece that contacts the plug and separates from the first connection piece in contact with the insertion of the plug into the jack
A viewfinder input switching device for a video camera, characterized in that it has a jack having a connecting piece.