JPH0969975A - Image pickup device and method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent unstable focusing when a long-distance scene is photographed. SOLUTION: Of a focus switch 5 consisting of a slide switch 21 and a momentary switch 22, the slide switch 21 is used to select an automatic mode, a manual mode, or an infinite-distance fixed mode. This slide switch 21 is fixed while switched to the automatic mode or manual mode, but not fixed in the infinite- distance fixed mode. Namely, while the switch is pressed down to the infinite- distance fixed mode, the focus is set to an infinite distance and when the pressing hand is put away, the focus returns to the state of the manual mode while set to the infinite distance. Further, when the manual mode is selected with the slide switch 21, the depression of the momentary key 22 places the device in the automatic mode.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image pickup apparatus and method which are applied to, for example, focus control of a VTR integrated video camera and can perform focus control at infinity.

[0002]

2. Description of the Related Art In a conventional autofocus device for a video camera, a focus lens is used so that an evaluation value obtained from a contrast component of a video signal is maximized on the basis of the concept of focusing when a high frequency component of the video signal is maximum. Auto focus operation is realized by driving. Specifically, as shown in FIG. 5, the direction and speed of the focus lens are controlled by the sign and size of the change (Δy) in the evaluation value when the focus lens is moved by a minute distance (Δx). Here, which part of the screen is targeted for autofocusing is determined by a frame on the screen (hereinafter referred to as a distance measurement frame) for obtaining the evaluation value.

[0003]

However, since the autofocus performance is improved and the focus is fast, for example, when a bird passes in front of a lens while shooting a distant view image, or when shooting from inside a car. There is a problem that the focus fluctuates because the object in front of the lens is focused, such as when a telephone pole appears in front of the lens.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to propose an image pickup apparatus and method which can easily suppress the fluctuation of the focus during photographing of a distant view image.

[0005]

According to a first aspect of the present invention, in an image pickup apparatus having an autofocus function, a manual focus mode, an autofocus mode, and a mode for fixing the focus at infinity are selectively set. The image pickup apparatus is provided with means for performing.

The invention according to claim 2 is an image pickup method having an autofocus function, wherein a manual focus mode, an autofocus mode, and a mode for fixing the focus at infinity are selectively set. Is an imaging method.

Since the infinity fixed mode can be selected in addition to the automatic mode and the manual mode as described above, it is possible to suppress the fluctuation of the focus in photographing a distant view image.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. VT to which the present invention can be applied
An example of an external view of the R-integrated video camera is shown in FIG. 1A,
FIG. 1B shows an example of a control panel of the VTR integrated camera. The strobe fixing portion indicated by 1 is provided on a handle, and a microphone 2 is further provided on the handle.
A tally lamp 3 and a front remote control light-receiving unit 4 are provided at the tip of the microphone 2, and the tally lamp 3 is a lamp for informing the user that photography is in progress.
Is a part that receives a control signal from the remote controller.

By switching the focus switch 5, any one of the auto focus mode (hereinafter referred to as the automatic mode), the manual focus mode (hereinafter referred to as the manual mode), and the infinity fixed mode is selected. The focus control range in this automatic mode has a range from the closest point to infinity, and the adjustment is automatically focused. Similarly, the focus control range in the manual mode also has a range from the closest point to infinity, but the adjustment is focused using the focus ring 6.

On the other hand, the focus control range of the infinity fixed mode becomes fixed at infinity when the infinity fixed mode is set. When the set infinity fixed mode is released, the mode returns to the manual mode in the fixed infinity state. The switch panel 7 collects general switches for recording / reproducing a magnetic tape.

An example of this switch panel 7 is shown in FIG. 1B. As shown in the figure, as buttons for running the magnetic tape, dubbing, frame advance (forward direction, backward direction), slow, recording, recording (DV input), stop, rewind, play,
Fast forward and pause are provided.

FIG. 2 shows the structure of an example of the autofocus device provided in the VTR-integrated video camera. In the figure, 11a to 11d are lens groups, lens groups 11a and 11c are fixed, lens group 11b is a zoom lens, and lens group 1
1d is a focus lens. Focus lens 11
Focus is controlled by moving the position of d in the optical axis direction by the step motor 12.

Reference numeral 13 is a CCD solid-state image pickup device, and an image pickup signal from this is supplied to a camera signal processing circuit 14. The video signal (luminance signal) Y output from the signal processing circuit 14 is converted into a digital signal by the A / D converter 15 and supplied to the high pass filter 16. The output signal of the high pass filter 16 is an absolute value circuit. It is converted into an absolute value in 17 and supplied to the peak hold circuit 18 as a contrast component.

The peak hold circuit 18 is supplied from the controller 19 with frame data SER designating a distance measuring frame. The peak hold circuit 18 detects the evaluation value (maximum value) from the signal corresponding to the inside of the distance measurement frame among the signals of each screen output from the absolute value circuit 17. The peak hold circuit 18 outputs the evaluation value data Dv and the data Dp indicating the screen position where the evaluation value is obtained, and the data Dv and Dp are supplied to the controller 19.

Then, in the focus switch 5,
When the automatic mode is selected, the controller 19 controls the step motor 12 based on the data Dv and Dp.
Control data Dc for controlling the rotation of the step motor 12 is formed.
Is supplied to. As a result, focus control is performed. Further, in the focus switch 5, when the manual mode is selected, the focus ring 6 is used for focusing as described above, and when the infinity fixed mode is selected, it is controlled by the step motor 12. The focus lens 11d is set to infinity.

An embodiment of the image pickup apparatus of the present invention will be described with reference to the focus switch 5 shown in FIG. The focus switch 5 shown in FIG. 3 includes a slide switch 21 and a tact key 22, and the slide switch 21 sets the focus mode to an automatic mode, a manual mode, or a fixed infinity mode. The switch of the slide switch 21 of this embodiment is fixed in a state of being switched to the automatic mode position and the manual mode position. However, the switch is configured to return to the manual mode position by the spring when the switch is pushed down to the infinity fixed mode position and then released.

That is, when the switch of the slide switch 21 is in the infinity fixed mode, the focus is set to infinity. Also, in the slide switch 21,
While the manual mode is set and the tact key 22 is pressed, the focus mode is set to the automatic mode (one push auto) and the focus is automatically focused. When the tact key 22 is released, the manual mode setting is restored with the released focus state.

As described above, the focus control range in the automatic mode has a range from the closest point to infinity, the adjustment is automatically focused, and the focus control range in the manual mode also has an infinite distance from the closest point. Although it has a distant range, its adjustment is focused by operating the focus ring 6. On the other hand, the focus control range of infinity fixed mode is fixed at infinity, and when infinity fixed mode is released,
Return to manual mode setting with focus at infinity.

That is, the controller 19 provided in association with the focus switch 5 always determines the state of the focus switch 5. When it is determined that the focus switch 5 is fixed in the infinity fixed mode, the focus lens 11d is set to infinity by the control based on the step motor 12. and again,
While the focus switch 5 continues to be determined to be fixed in the infinity fixed mode, the focus lens 11d
Is set to infinity by the step motor 12.

Then, the focus switch 5 of the present invention
Modifications will be described. The focus switch 5 shown in FIG. 4A includes a slide switch 21 and a tact key 22, and the focus mode of the slide switch 21 is set to the automatic mode, the manual mode, or the push-auto mode. The switch of this slide switch 21 is
In the position of the automatic mode and the position of the manual mode, they are fixed, but in the position of the push automatic mode, when they are released to the position of the push automatic mode without fixing, the spring returns them to the position of the manual mode. When the switch of the slide switch 21 is fixed to the push automatic mode position, the focus mode is set to the automatic mode. Further, no matter what the setting of the slide switch 21 is, the focus mode is set to the infinite fixed mode while the tact key 22 is being pressed.

Next, the focus switch 5 shown in FIG. 4B.
Consists of a slide switch 21 and a tact key 22,
In the slide switch 21, the focus mode is set to the automatic mode or the manual mode. The switch of the slide switch 21 is fixed in a state of being switched to the automatic mode position and the manual mode position. Further, no matter what the setting of the slide switch 21 is, the focus mode is set to the infinite fixed mode while the tact key 22 is being pressed.

The focus switch 5 shown in FIG. 4C is used for a model dedicated to autofocus. The focus switch 5 at this time is composed of a tact key 22, and while the tact key 22 is being pressed, the focus mode is set to the infinite fixed mode.

Further, the focus switch 5 shown in FIG. 4D is used.
Consists of a slide switch 21 and a tact key 22,
In the slide switch 21, the focus mode is set to the automatic mode or the manual mode. The switch of the slide switch 21 is fixed in a state of being switched to the automatic mode position and the manual mode position. Further, while the slide switch 21 is set to the manual mode and the tact key 22 is pressed, the focus mode is set to the infinity fixed mode.

Next, the focus switch 5 shown in FIG. 4E.
Includes a slide switch 21, and the slide switch 21 sets the automatic mode or the fixed infinity mode. The switch of the slide switch 21 is fixed in a state of being switched to the position of the automatic mode and the position of the fixed mode at infinity.

The focus switch 5 shown in FIG. 4F is composed of a slide switch 21, and the slide switch 21 sets the automatic mode, the manual mode, or the infinity fixed mode. This slide switch 2
The switch of No. 1 is fixed in a state of being switched to the position of the automatic mode, the position of the manual mode, and the position of the fixed infinity mode.

As described above, the image pickup apparatus of the present invention can be used for various settings by using the focus switch 5 (that is, the slide switch 21 and / or the tact key 22). Further, while the tact key 22 is pressed as described above, it is possible to set the focus mode to the infinity fixed mode (or the mode set to the tact key 22), but when pressed, the infinite fixed mode is set. It is also possible to set it so that the infinity fixed mode is released by pressing again.

In this embodiment, the focus control is performed by the control panel of the VTR integrated video camera, but it is also possible to perform the focus control by using the remote controller.

The present invention can also be applied to video cameras, electronic still cameras (analog or digital) and film cameras.

Further, in this embodiment, the operation of the present invention is performed using the operation keys of the control panel, but the operation of the present invention can be performed by operating the remote controller.

[0030]

According to the present invention, the focus can be easily set to infinity by setting the infinity fixed mode when shooting a distant view image.

[Brief description of drawings]

FIG. 1 is an external view showing an embodiment of a VTR-integrated video camera according to the present invention.

FIG. 2 is a block diagram showing an embodiment of a VTR-integrated video camera according to the present invention.

FIG. 3 is a schematic diagram for explaining an embodiment of the image pickup apparatus of the present invention.

FIG. 4 is a schematic diagram for explaining a modified example of the image pickup apparatus of the present invention.

FIG. 5 is a graph used to describe an example of autofocus.

[Explanation of symbols]

 21 slide switch 22 tact key

Claims (2)

[Claims] 1. An image pickup apparatus having an autofocus function, comprising means for selectively setting a manual focus mode, an autofocus mode, and a mode for fixing the focus at infinity. 2. An image pickup method having an autofocus function, wherein a manual focus mode, an autofocus mode, and a mode for fixing the focus at infinity are selectively set.