JPH04362878A - Automatic diaphragm apparatus - Google Patents

Abstract

PURPOSE:To obtain an automatic diaphragm apparatus that is made simple and that can also manually controlled. CONSTITUTION:In order to manually controlling this diaphragm, a manual operating panel 12 is operated, this diaphragm apparatus sends a diaphragm operating signal to a computer 13. The computer 13, based on the diaphragm operating signal, outputs a diaphragm control signal to a digital control gain adjust circuit 15 of an auto-iris circuit A. The digital control gain adjust circuit 15 adjusts the gain of a composite signal of a picture signal and a diaphragm control signal and outputs the result to a waveform shaping circuit 16. The waveform shaping circuit 16 shapes the waveform of the composite signal, outputs the result to a level wave detecting circuit 3, and the level wave detecting circuit 3 detects the level of the composite signal. A motor drive circuit 4, based on the difference between the composite signal and a reference level signal, controls a diaphragm adjust motor 6 to adjust the diaphragm.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic aperture device used in television cameras, video cameras, surveillance cameras, etc.

0002

2. Description of the Related Art Conventionally, surveillance cameras and the like have been provided with an auto-iris circuit, which drives an aperture adjustment motor of the camera based on the level of an input video signal. Further, the aperture can be adjusted by manual remote control, and in this case, for example, the aperture is constantly adjusted manually, or the aperture position is memorized and the adjustment is performed under the control of a microcomputer or the like.

FIG. 3 shows a device capable of automatic and manual aperture. In this device, in the automatic aperture mode, a video signal (video signal or composite signal) from a video camera is amplified by a signal amplification circuit 1, and waveform-shaped and level-adjusted by a waveform-shaping level adjustment circuit 2. and,
The level of the level-adjusted signal is detected by a level detection circuit 3 to detect the level of the video signal. The motor drive circuit 4 controls the aperture adjustment motor 6 and adjusts the aperture based on the difference between the level of the video signal from the level detection circuit 3 and the reference level signal, using the reference level signal output by the reference level generation circuit as a reference. do.

On the other hand, in order to perform manual operation, the selector switch 11 is switched to the manual mode side, and then the operation panel is operated arbitrarily, and the control signal ( A digital signal of about 8 bits) is converted into an analog signal by a D/A conversion circuit 9, and the converted analog signal drives a motor drive circuit 10 via a differential amplification loop filter 8. The aperture adjustment motor 6 is controlled by the motor drive circuit 10 to adjust the aperture. That is, a potentiometer 7 is linked to the output shaft of the aperture adjustment motor 6, and the output voltage of the potentiometer 7 is input to the differential amplification loop filter 8 to drive the aperture adjustment motor via the motor drive circuit 10. 6 is servo controlled.

[0005]

However, when controlling the aperture manually, not only an expensive potentiometer 7 is required to detect the position of the rotating shaft of the aperture adjustment motor 6, but also a changeover switch 31 is required. Therefore, there was a problem that the cost was inevitably high and the number of parts was also increased. The present invention has been made in order to solve the problems of the prior art, and an object of the present invention is to provide an automatic diaphragm device that can perform manual diaphragm with a simple configuration.

[0006]

[Means for Solving the Problems] A first invention includes an auto iris circuit that outputs a motor drive signal based on a video signal, and a motor drive circuit that drives and controls an aperture adjustment motor based on the motor drive signal. The gist of the automatic iris device is that the auto iris circuit is provided with a level adjustment section that inputs an iris control signal from a manual operating means and outputs a motor drive signal based on the iris control signal. be.

The second invention includes an auto iris circuit that outputs a motor drive signal based on a video signal, and an aperture adjustment motor based on the motor drive signal from the auto iris circuit using the reference level signal from the reference level generation circuit as a reference. In the automatic aperture device, the reference level generating circuit receives an aperture control signal from a manual operating means and changes the reference level signal based on the aperture control signal. This is the gist of the matter.

[0008]

[Operation] In the first invention, when manually adjusting the aperture, an aperture control signal is sent from the manual operation means. Then, the level adjustment section of the auto iris circuit outputs a motor drive signal to the motor drive circuit based on the aperture control signal and video signal. The motor drive circuit drives the aperture adjustment motor based on the motor drive signal.

In the second aspect of the invention, when manually adjusting the aperture, an aperture control signal is sent from the manual operation means. Then, the reference level generation circuit changes the reference level signal in the direction of opening or closing the aperture based on the aperture control signal. The motor drive circuit uses the changed reference level signal as a reference and drives the aperture adjustment motor based on the motor drive signal.

0010

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the first invention is embodied in an automatic aperture device for a surveillance camera that can be remotely controlled will be described below with reference to FIG. Note that the same components as those in the conventional example are given the same reference numerals, and the description thereof will be omitted. The manual operation panel 12 is connected to the computer 13 and is used to input operation signals for performing various manual controls on the surveillance camera. The computer 13 outputs various control signals for remote control to the surveillance camera based on the operation signals from the manual operation panel 12. The manual operation panel 12 and the computer 13 constitute a manual operation means.

The auto iris circuit A constituting the automatic aperture device of a surveillance camera (not shown) is constructed as follows. A digital control gain adjustment circuit 15 serving as a level adjustment section in the auto iris circuit A is connected to the next stage of the signal amplification circuit 1, and inputs the video signal from the signal amplification circuit 1 during automatic aperture, and inputs the video signal from the signal amplification circuit 1 to the computer 13 during manual aperture remote control. Input the aperture control signal from. Note that this aperture control signal is a digital signal. When the digital control gain adjustment circuit 15 receives the video signal from the signal amplification circuit 1 alone or receives the video signal and the aperture control signal, it adjusts the gains thereof and outputs the signal to the waveform shaping circuit 16 at the next stage. The waveform shaping circuit 16 shapes the input signal into a waveform and outputs it to the level detection circuit 3.

The auto iris circuit A of this embodiment is composed of a signal amplification circuit 1, a digital control gain adjustment circuit 15 as an adjustment section, a waveform shaping circuit 16, and a level detection circuit 3. Further, the motor drive circuit 4 and the auto iris circuit A constitute an automatic aperture device.

Now, when the automatic aperture device for a surveillance camera configured as described above performs automatic aperture, when the signal amplification circuit 1 receives a video signal (a composite signal may be used) as a video signal from the surveillance camera, Signal amplification circuit 1
amplifies the signal, and the digital control gain adjustment circuit 15 adjusts the gain of the signal. Next, the signal is waveform-shaped by the waveform shaping circuit 16. Then, the level of the video signal of the waveform-shaped signal is detected by a level detection circuit 3. The motor drive circuit 4 controls the aperture adjustment motor 6 based on the difference between the level of the video signal from the level detection circuit 3 and the reference level signal from the reference level generation circuit 5, and adjusts the aperture.

On the other hand, to perform manual operation, the manual operation panel 12 is operated and an aperture operation signal is sent to the computer 13. The computer 13 outputs a control signal to the digital control gain adjustment circuit 15 of the auto-iris circuit A based on the aperture operation signal. The digital control gain adjustment circuit 15 receives the video signal and the aperture control signal, synthesizes them, adjusts the gain of the composite signal, and outputs the signal to the waveform shaping circuit 16 at the next stage. The waveform shaping circuit 16 shapes the input signal into a waveform,
Output to level detection circuit 3. The level detection circuit 3 detects the level of the composite signal, and the motor drive circuit 4 controls the aperture adjustment motor 6 based on the difference between the level of the composite signal from the level detection circuit 3 and the reference level signal of the reference level generation circuit 5. and adjust the aperture.

Even when the aperture is controlled manually in this manner, manual aperture adjustment can be performed using the auto iris circuit A, which is common to the automatic aperture. Next, an embodiment of the second invention will be described with reference to FIG. In this embodiment, a signal amplification circuit 1, a waveform level adjustment circuit 2, and a level detection circuit 3 are used as in the conventional one.
A computer 13 is connected to a reference level generation circuit 18 that outputs a reference level signal to the motor drive circuit 4, and receives an aperture control signal output from the computer 13. . When the reference level generating circuit 18 receives the aperture control signal, it changes the reference level signal in the opening direction or the aperture direction in accordance with the input aperture control signal and outputs it to the motor drive circuit 4.

Therefore, in this embodiment, in the case of automatic aperture,
The aperture is controlled in the same way as before. On the other hand, to perform manual operation, the manual operation panel 12 is operated and an aperture operation signal is sent to the computer 13. The computer 13 outputs an aperture control signal to the reference level generation circuit 18 based on the aperture operation signal. When the reference level generating circuit 18 receives the aperture control signal, it changes the reference level signal in the opening direction or the aperture direction in accordance with the input aperture control signal and outputs it to the motor drive circuit 4. The motor drive circuit 4 controls the aperture adjustment motor 6 based on the difference between the video signal and the changed reference level signal, and adjusts the aperture.

In this embodiment as well, when the aperture is controlled manually, the auto iris circuit A, which is common to the automatic aperture, allows manual aperture adjustment. It should be noted that the present invention is not limited to the above-mentioned embodiments, and the aperture control signal can be arbitrarily changed without departing from the spirit of the invention, such as changing the diaphragm control signal to a voltage control signal even if it is an analog signal. be.

[0018]

[Effects of the Invention] As detailed above, the present invention has a simple configuration, allows manual aperture adjustment, does not require the use of potentiometers, changeover switches, etc., and can reduce the number of parts. It has excellent effects and can be made at low cost.

[Brief explanation of drawings]

FIG. 1 is an electrical block circuit diagram showing an embodiment of the first invention.

FIG. 2 is an electrical block circuit diagram showing an embodiment of the second invention.

FIG. 3 is an electrical block circuit diagram of a conventional device.

[Explanation of symbols]

A...Auto iris circuit, 1...Signal amplification circuit, 3...Level detection circuit, 5...Reference level generation circuit, 6...Aperture adjustment motor, 12...Manual operation panel, 13...Computer, 15...
Digital control gain adjustment circuit, 16...Waveform shaping circuit, 1
8...Reference level generation circuit.

Claims (2)

[Claims] 1. An automatic iris device comprising an auto iris circuit that outputs a motor drive signal based on a video signal, and a motor drive circuit that drives and controls an iris adjustment motor based on the motor drive signal, wherein the auto iris circuit An automatic diaphragm device comprising a level adjustment section that receives an iris control signal from a manual operating means and outputs a motor drive signal based on the iris control signal and video signal. 2. An auto iris circuit that outputs a motor drive signal based on a video signal, and a reference level signal from a reference level generation circuit that controls driving of an aperture adjustment motor based on a motor drive signal from the auto iris circuit. In the automatic aperture device equipped with a motor drive circuit, the reference level generation circuit is configured to input an aperture control signal from a manual operation means and change the reference level signal based on the aperture control signal. automatic squeezing device.