JPH0233269A - Television cameras and surveillance equipment using them - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a television camera suitable for rear monitoring of automobiles, etc., and a monitoring device using the same. It concerns a device that can be changed.

[Prior art]

2. Description of the Related Art Monitoring devices have been proposed in which a television camera is attached to the rear of large automobiles and the like to check and monitor the rear, and the video output is checked from the driver's seat. It is necessary to change the direction of the camera when looking directly behind the car and when checking the distance between cars behind.

〔assignment〕

As mentioned above, it is necessary to mechanically change the direction of the camera in order to change the range of confirmation and monitoring. Therefore, a drive mechanism is required, and a control mechanism and the like are also required.

Furthermore, a mechanism for attaching them is also required, which increases the number of parts as a whole and causes problems in terms of strength.

The present invention attempts to solve the above problems.

[Means to solve the problem]

The present invention solves the above problems by electrically varying the photographic range of the camera.

That is, in a television camera that scans an image pickup plate by deflecting an electron beam using the output of a deflection circuit, the output of a DC bias circuit is input to the deflection circuit, and the output level of the deflection circuit is changed, thereby changing the scanning range. The feature is that it is variable.

Furthermore, in a monitoring device that uses a television camera that scans an image pickup plate by deflecting an electron beam using the output of a deflection circuit and outputs the image to a monitor, the output of a DC bias circuit is input to the deflection circuit of the television camera, and the output of a DC bias circuit is input to the deflection circuit of the television camera. It is characterized in that the scanning range is made variable by changing the output level of the deflection circuit, and the range from which an image is obtained is made variable.

Changes in the deflection output can be realized by changing the resistance value of a variable resistor connected to the DC bias circuit.

〔Example〕

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

Generally, in a television camera, only the central portion of the image pickup plate is used, avoiding the edges. This is to use a range in which the characteristics of the lens and image pickup plate do not deteriorate. Also, in scanning to obtain an image from the image pickup plate, the deflection output is set so that only that portion is scanned. for example,
As shown in FIG. 3 (al), a deflection output is obtained in the range of +1.OV to -1.OV, and the current in the deflection coil is thereby controlled to deflect the electron beam and scan it.

In the present invention, the value of the above voltage is changed, for example, the third
+2 as shown in figure (b). Obtain a deflection output ranging from Ov to Ov. This changes the current in the deflection coil and changes the deflection range of the electron beam. This also changes the scanning range of the imaging plate.

As mentioned above, by changing the scanned range,
This produces the same effect as changing the direction of the camera. If the edge of the image pickup plate is used, the quality of the image will be slightly degraded not only due to its characteristics but also due to lens distortion, etc., but this will not be much of a problem if it is used in a monitoring device or the like.

In order to change the above deflection output, current is supplied from the power supply through a DC bias circuit as shown in FIG. A predetermined bias voltage is applied to the deflection circuit by a DC bias circuit. A variable resistor is connected to the DC bias circuit, and the bias voltage output from the DC bias circuit changes depending on the resistance value of the variable resistor. This changes the current flowing through the deflection coil and changes the scanned range.

In the example shown in FIG. 1, the scanning range in the vertical direction, that is, the vertical deflection, is variable. For example, in a rearview monitoring device for an automobile, the setting is normally made such that the horizontal direction of the camera is the upper limit of the screen when the variable resistor is at its maximum or minimum resistance value. By gradually changing the resistance value of the variable resistor, the lower part of the screen is gradually projected. Then, when the resistance value changes the most, it is possible to project directly after the car, that is, in the vertical direction.

If the variable resistor described above is installed in the driver's cab, it becomes possible to change the direction of the image while rotating the knob of the variable resistor from the driver's seat.

In addition, in the above-mentioned vehicle rear monitoring device, etc., it is often better to obtain a larger image immediately after the blind spot. Therefore, as shown in FIG. 2, it is preferable to connect a relay and operate it to obtain a zoomed image. As shown in FIG. 4, the bias voltage is inputted from the terminal 41, and includes means for detecting that the voltage reaches a predetermined value.
, thereby energizing the coil and relay 44.
can be operated.

If the above-mentioned zoom means is provided, for example, in the above-mentioned monitoring device, the screen will gradually change downward, and the relay will be activated when the screen reaches its lowest point, that is, when the image immediately afterward is displayed. If you do so, the image in that direction will automatically switch to zoom. When the resistance value is changed in the opposite direction again, the relay is deactivated and the image switches to a normal image.

Note that the variable resistor described above is not limited to being continuous, but may be switched stepwise by using a switch or the like. Thereby, the operating point of the relay can be switched to several stages. Also, although the explanation dealt with the example of vertical deflection,
Similar switching of the scanning range is also possible in horizontal deflection. Further, the circuit configuration may be substantially the same.

Note that the technical idea shown in the present invention applies to MOS type and CCD
It is also applicable when using an imaging device.

〔effect〕

According to the present invention, it is possible to electrically change the direction of the camera, and remote control is also possible using only a cable.

Therefore, it is possible to reduce the size and weight of the device including the mounting part, which is particularly advantageous for automobile rear monitoring devices and the like.

[Brief explanation of the drawing]

1 and 2 are detailed explanatory diagrams of the present invention, FIG. 3 is an explanatory diagram of the deflection output voltage, and FIG. 4 is a circuit diagram of an example of the zoom switching means.

Claims (6)

[Claims] (1) In a television camera that scans an image pickup plate by deflecting an electron beam using the output of a deflection circuit, the output of a DC bias circuit is input to the deflection circuit, and the output level of the deflection circuit is changed, thereby controlling the scanning. A television camera characterized by a variable range. (2) The television camera according to claim 1, wherein the vertical scanning range is made variable by changing the vertical deflection output level. (3) A variable resistor is connected to the DC bias circuit, and the DC bias is changed by changing the resistance value of the variable resistor,
2. The television camera according to claim 1, wherein the output level of the deflection circuit is thereby changed. (4) In a monitoring device that uses a television camera that scans an image pickup plate by deflecting an electron beam using the output of a deflection circuit and outputs the image to a monitor, the output of a DC bias circuit is input to the deflection circuit of the television camera. A monitoring device characterized in that the scanning range is made variable by changing the output level of the deflection circuit, and the range in which images are obtained is made variable. (5) The monitoring device according to claim 5, wherein the vertical scanning range is changed by changing the vertical deflection output level of the deflection circuit, and the vertical video output range is made variable. (6) The monitoring device according to claim 4, wherein a variable resistor is connected to the DC bias circuit, and the video output range is made variable by changing the resistance value of the variable resistor.