JPH052205A - Focus command device - Google Patents

Abstract

PURPOSE:To select an optimum mode according to a photography state by providing plural operation modes wherein a focus position is varied. CONSTITUTION:When a cameraman selects one of the operation modes of a characteristic selection part 13, the characteristic selection part 13 outputs the selected operation mode to an arithmetic circuit 12. In this case, a manipulated variable detection part 10 detects and converts a manipulated variable into an electric signal and outputs this analog signal to an A/D converter 11, which converts it into a digital operation signal and outputs the signal to the arithmetic circuit 12. The arithmetic circuit 12 sends the selected mode from from the characteristic selection part 13 to a conversion parameter part 14, receives the parameter of the corresponding mode from the conversion parameter part 14, and outputs an operation mode as a command signal corresponding to the mode to a D/A converter 15 in the form of a digital signal; and the signal is converted into an analog signal, which is outputted to a focus servo device 16 to vary the focus position of a lens 17.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a focus command device which outputs a command signal for varying the focal position of a lens of a television camera.

[0002]

2. Description of the Related Art As shown in FIG. 6, a conventional focus command device in a television camera is a control unit operated by a cameraman by an operation detection unit 1 including a potentiometer and an encoder provided on the camera body side, the lens side or the outside. A focus servo device 3 that detects a rotation angle, that is, an operation amount, and provides a command signal proportional to the operation amount on the lens 2 side
Output to and the focal position of the lens is changed. By this operation, focusing on an arbitrary subject is performed.

Further, in another type of focus command device, as shown in FIG. 7, a non-linear conversion provided on the lens 2 side between the camera body side, the lens side or the external operation detecting section 1 and the focus servo device 3 is performed. The focus position with respect to the operation amount is changed non-linearly via the circuit 4.

[0004]

Originally, the change of the focus position in the photographing environment is caused by the habit and preference of the cameraman's operation.
Depending on the difference between the long focus and short focus of the lens, the difference between the studio and sports broadcast, etc., the speed of change of the focus position with respect to the operation amount should be different, but in any conventional method, the operation characteristics, that is, the operation amount of the cameraman Since the amount of change in the focus position with respect to is fixed linearly or non-linearly, it is difficult to change the focus of the camera with the optimal operating characteristics for the shooting environment.

An object of the present invention is to provide a focus command device which is provided with a plurality of operation modes and which allows a cameraman to select the optimum mode for changing the focus according to the photographing situation.

[0006]

A focus command device according to the present invention for achieving the above object is a focus command device for outputting a command signal for varying a focal position of a lens of a television camera in a plurality of operation modes. And a mode selecting means for storing the operation mode and outputting the selected mode, and a converting means for converting the operation amount of the cameraman into the command signal according to the mode from the mode selecting means. ..

[0007]

The focus command device having the above-mentioned configuration selects a target mode from a plurality of operation modes stored in the mode selection means, and the conversion means converts the operation amount of the cameraman into a command signal corresponding to this mode.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail with reference to the embodiments shown in FIGS. FIG. 1 is a block diagram showing the first embodiment. The output of the operation amount detection unit 10 that detects the operation amount of an operation rod (not shown) operated by the cameraman and converts it into an electric signal is connected to the arithmetic circuit 12 via the A / D converter 11. Further, the arithmetic circuit 12 has a plurality of operation modes and is connected to a characteristic selection unit 13 that outputs the selected mode. The arithmetic circuit 12 further includes a conversion parameter unit 14
The output of the arithmetic circuit 12 is connected to the focus servo device 16 via the D / A converter 15. It should be noted that the operation amount detection unit 10 to the D / A converter 15 are provided on the camera body side, and the focus servo device 16 is the lens 1
It is provided on the 7 side.

Prior to photographing, the photographer selects the characteristic selection unit 1
When one of the plurality of operation modes 3 is selected, the characteristic selection unit 13 outputs the selected operation mode to the arithmetic circuit 12. The operation amount detection unit 10 detects the operation amount, converts the operation amount into an electric signal, and outputs an analog signal to the A / D converter 11.
The D converter 11 converts this into a digital signal operation signal and outputs it to the arithmetic circuit 12. The arithmetic circuit 12 sends the selection mode from the characteristic selection unit 13 to the conversion parameter unit 14,
The parameter of the corresponding mode is received from the conversion parameter unit 14, and thereby the operation signal is output to the D / A converter 15 as a digital signal as a command signal corresponding to the mode. The D / A converter 15 converts the command signal into an analog signal and outputs it to the focus servo device 16 to change the focal position of the lens 17.

FIG. 2 shows a characteristic diagram of the operation modes set in the conversion parameter section 14, for example, four kinds of operation modes a to d are used. Here, the horizontal axis represents the operation amount from the position A of the operating rod to the position B, and the vertical axis represents the focus position. The change amount of the focus position with respect to the operation amount is the operation mode a.
~ D.

For example, when the mode a is selected, as the operation amount changes from the position A to the position B, the focal position changes abruptly on the near side and gradually changes on the infinite side. Mode c has the opposite characteristic, and mode b has an intermediate characteristic between a and c.
In the mode d, as the operation amount changes from the position A to the position B, the focus position changes from infinity to the close distance, and has the opposite characteristic to the mode b in the same operation.

Further, while moving the camera, the focus can be changed from focus in (focus point) to focus out (out of focus) by the operating lever, so that the screen can be changed from hard to soft, and further the screen can be changed. fade·
Techniques such as shifting to in (dark dissolution) can be used together.
In this way, the cameraman can create various images by selecting the mode based on his aesthetic sense according to the shooting environment.

FIG. 3 is a block diagram showing the second embodiment.
The output of the manipulated variable detector 10 is connected in parallel to each input of the plurality of non-linear conversion circuits 21 to 24 each having a mode. The outputs of the conversion circuits 21 to 24 are connected to a plurality of input terminals corresponding to the modes of the output selection circuit 25, and the output of the output selection circuit 25 is connected to the input of the focus servo device 16 provided in the lens 17. Has been done.

Each of the non-linear conversion circuits 21 to 24 has a parameter corresponding to one of the operation modes as shown in FIG. 2, and the operation signal from the operation amount detecting section 10 is converted by each parameter to correspond to the mode. Different command signals are output to the output selection circuit 25. When the selection signal for selecting the operation mode is input to the output selection circuit 25, the input of the corresponding mode is activated and only the corresponding command signal is output to the focus servo device 16. Therefore, similar to the first embodiment. The lens 17 can be controlled by the focus servo device 16 according to the operation mode.

In some cases, it may be desirable to specialize the operation modes a to d shown in FIG. 2 in accordance with the difference in the lens configuration, for example, the model of the lens such as long focus and short focus zoom. 4 and 5 are configuration diagrams showing an embodiment in which the operation mode is dedicated to each lens.

FIG. 4 shows a third embodiment, which has the same configuration as that of the first embodiment, but is provided on the lens 17 side except for the manipulated variable detector 10 and has a dedicated mode. In addition, FIG. 5 shows a fourth embodiment, which has the same configuration as the second embodiment, but is provided on the lens 17 side except for the operation amount detection unit 10 and dedicated to the mode.

[0017]

As described above, the focus command device according to the present invention has a plurality of predetermined operation modes, so that the cameraman can select the most suitable mode for photographing and easily create various images. It is possible to improve the screen effect.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a first embodiment.

FIG. 2 is a characteristic diagram of an operation mode.

FIG. 3 is a configuration diagram of a second embodiment.

FIG. 4 is a configuration diagram of a third embodiment.

FIG. 5 is a configuration diagram of a fourth embodiment.

FIG. 6 is a configuration diagram of a fifth embodiment.

FIG. 7 is a configuration diagram of a conventional example.

[Explanation of symbols]

 10 manipulated variable detection unit 11 A / D converter 12 arithmetic circuit 13 characteristic selection unit 14 conversion parameter unit 15 D / A converter 16 servo device 17 lens 21 to 24 non-linear conversion circuit 25 output selection circuit

Claims (1)

Claim: What is claimed is: 1. A focus command device for outputting a command signal for changing a focal position of a lens of a television camera in a plurality of operation modes, a mode selection for storing the operation mode and outputting the selected mode. A focus command device comprising: means for converting the operation amount of the cameraman into the command signal according to the mode from the mode selecting means.