JPH0286272A - Video camera - Google Patents

Abstract

PURPOSE:To attain simple tilting and panning by providing an automatic tilting switch, an automatic panning switch, a detection means detecting the turning position in the pitching direction and the yawing direction of a lens system respectively and a controller. CONSTITUTION:When the automatic tilting switch 27 is turned on, the controller 26 fetches an output signal of a position detection circuit 24 to read the position of a zoom lens system 1, drives the zoom lens system 1 operating an actuator 4 around a pivot shaft 9, an output signal of a displacement detection circuit 3 is fetched to apply automatic tilting. Moreover, even when the automatic panning switch 28 is turned on, the controller 26 fetches an output signal of a position detection circuit 25 and a displacement detection circuit 12 to operate an actuator 18 thereby applying automatic panning. Thus, the automatic tilting and panning are applied in a range set by the user.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a portable video camera such as a video camera with an integrated VTR or an electronic camera, and particularly relates to a video camera equipped with an image stabilization device. Regarding.

[Conventional technology]

In recent years, video cameras with integrated VTRs have become popular, but these were developed for portable use.
It is usually carried and used outdoors.

In addition, there are many opportunities to take images while walking or on a moving vehicle, and in such cases, vibrations are transmitted to the camera body, causing image blur. Furthermore, even when capturing an image while standing still, if the zoom ratio is set to about 6 to 8 times and telephoto capturing is performed without using a fixing device such as a tripod, image shake becomes noticeable due to camera shake, resulting in an extremely difficult to view image.

Conventional methods for preventing image shake include using a gyro to ensure that the camera is always fixed in the direction of gravity, and using an acceleration sensor to detect the vibrations of the electric pan head to which the camera is attached as acceleration and angular velocity. However, methods have been proposed for driving the electric pan head so that these vibrations are offset.

However, both methods, such as driving the entire camera casing by a motor, have the disadvantage of making the entire camera including the anti-shake device larger and heavier, making it difficult to use a portable camera such as a VTR-integrated video camera. It is difficult to apply these methods to other cameras.

To solve this problem, for example, Japanese Patent Application Laid-Open No. 1986-
No. 240778 discloses that actuator means for rotationally driving the lens barrel section of the camera in the pitching direction and yawing direction, and detection means for detecting the rotation angle and angular velocity of the lens barrel section in these directions, are provided. A device is disclosed that prevents vibration of the lens barrel, and thus the camera, by feeding back the rotation angle and angular velocity to each actuator.

[Problem to be solved by the invention]

On the other hand, when using such a portable video camera to capture an image of a moving subject, the user must hold the video camera and change its orientation so that the lens system always faces the subject. However, it is very difficult for general users to accurately track and image a moving subject. For example, when imaging a subject moving laterally, the video camera must be rotated about an axis perpendicular to the ground, but when the user changes direction, there is also vertical movement, which causes will swing significantly.

Conventionally, in order to capture stable images of such moving subjects, the video camera was placed on a pan head and the pan head was rotated or tilted using a pan rod to swing the video camera up and down. Or.

(tilting) or rotate left and right (panning).
are doing.

However, when carrying a portable video camera, such a pan head cannot be used, resulting in the above-mentioned inconvenience.

The objective of NoL Kanmei is to provide a video camera having an image stabilization device that eliminates such problems and allows easy tilting and panning by operating a switch.

[Means to solve the problem]

In order to achieve the second object, the present invention provides, in addition to an image blur prevention device, an automatic tilting switch, an automatic panning switch, and a first device that detects the rotational position of the lens system in the pitching direction and the yawing direction, respectively. , a second position detection means, and a controller roller.

[Effect]

When automatic tilting is operated, the controller takes in the detection output of the first position detection means, drives the actuator of the image blur prevention device, and rotates the lens system in the pitching direction. This performs tilting. Further, when the automatic panning switch is operated, the controller receives the detection output of the second position detection means and drives the actuator of the one-image blur prevention device to rotate the lens system in the yawing direction. This performs panning.

In this way, tilting and panning can be performed using the image blur prevention device.

〔Example〕

First, an image blur prevention device used in a video camera according to the present invention will be explained.

FIG. 4 is a configuration diagram showing a specific example of such an image stabilization device, in which ■ is a zoom lens system, 2 is an angular velocity sensor,
3 is a displacement detection circuit, 4 is an actuator drive circuit, 5
is the motor, and 6 is the worm.

7 is the actuator, 8 is the gimbal, 9 is the pivot axis,
10 is a worm wheel, 11 is an angular velocity sensor, 12 is a displacement detection circuit, 13 is an actuator drive circuit, 14
is the motor, 15 is the worm, 16 is the actuator, 1
7 is a worm wheel, 18 is a pivot axis, 19 is an image sensor, 20 is a camera circuit, and 21 is a camera body.

In the figure, in a camera body 21 of a video camera, a zoom lens system is integrated with an image sensor 19 (here, 19 is a circuit board section on which an image sensor is installed, but for the sake of explanation, it is referred to as an image sensor). The output signal of the image sensor 19 is amplified and then supplied to the camera circuit 20 for signal processing.

Now, the optical axis direction of the zoom lens system 1 is the X axis, the horizontal direction perpendicular to this is the y axis, and the vertical direction perpendicular to this axis is the 2 axis.
Assuming three-dimensional coordinates as the axes, the zoom lens system 1 has a horizontal axis in the y-axis direction passing through the center of gravity of the zoom lens system 1 including the image sensor 19, and a horizontal axis on both sides of the outer wall surface of the zoom lens system 1. A worm wheel 10 is fixed.

However, only the worm wheel 10 on the near side is shown, and the worm wheel 10 on the opposite side is not shown. Further, the center of gravity is on the optical axis of the zoom lens system 1, and the center axis is perpendicular to the tangent of the intersection of the center and the outer wall surface of the zoom lens system 1. In other words, the central axis is the worm wheel 10
It becomes the center axis of rotation.

On the other hand, the gimbal 8 is provided with a pair of horizontally opposing pivot shafts 9 (however, only the pivot shaft 9 on the near side is shown), the tips of which are pressed against the rotational center point of the worm wheel 10. Therefore, zoom lens system 1
is supported by a gimbal 8 so as to be rotatable about the central axis in the y-axis direction, that is, in the pitching direction, with the pivot shaft 9 as a fulcrum.

A motor 5 is attached to the gimbal 8 so that its rotation axis is perpendicular (in the Z-axis direction), and a worm 6 is integrated with one rotation axis. This worm 6 meshes with a worm wheel 10. Worm 6 and worm wheel 1
0 constitutes a worm gear, and the motor 5 and worm 6 constitute an actuator 7 for rotating the zoom lens system 1 around a pivot shaft 9, that is, in the pitching direction.

Further, a worm wheel 17 is integrally attached to the lower surface of the mounting portion of the motor 5 in the gimbal 8, with the rotation center axis being a vertical axis (in the Z-axis direction) passing through the center of gravity of the zoom lens system 1. A pivot shaft 18 fixed to a support (not shown) is pressed against the rotational center axis of this worm wheel 17, and a similar pivot shaft 18 is also pressed on the portion of the gimbal 8 that faces the worm wheel 17.
By being pressed, the gimbal 8 is supported by a support body (not shown) so as to be rotatable about the central axis in the Z-axis direction, that is, in the yawing direction, with the pivot shaft 18 as a fulcrum.

The motor 14 is installed so that its rotation axis is horizontal (parallel to the xy plane), and the worm 1 is attached to this rotation axis.
5 are integrated. The worm 15 and the worm wheel 17 mesh with each other to form a worm gear, and the motor 14 and the worm 15 are connected to the pivot shaft 1.
Mainly 8.

That is, an actuator 16 for rotating the gimbal 8 and therefore the zoom lens system 1 in the yawing direction.
It consists of

The zoom lens system 1 is equipped with an angular velocity sensor 2 that detects the angular velocity of the zoom lens system 1 in the pitching direction due to vibrations transmitted to the camera body 17, and an angular velocity sensor 11 that similarly detects the angular velocity in the yawing direction. . Instead of these angular velocity sensors 2 and 11, an acceleration sensor that detects acceleration may be used.The output signal of the angular velocity sensor 2 is time-integrated by a displacement detection circuit 3, and the rotational displacement θ of the zoom lens system 1 in the pitching direction is A signal representing . Actuator drive circuit 4 responds to this signal.
drives the motor 5. Similarly, the output signal of the angular velocity sensor 11 is time-integrated by the displacement detection circuit 12 to generate a signal representing the rotational displacement ψ of the zoom lens system 1 in the yawing direction. Actuator drive circuit 13 drives motor 14 in response to this signal.

Here, the image blur prevention operation in this embodiment will be explained.

Generally, when capturing images of landscapes or people using a video camera, the causes of image blur are vibrations caused by camera shake and vibrations transmitted from a moving vehicle when capturing an image.

FIG. 5 shows the results of measuring the vibration state of a portable video camera using an angular velocity sensor when the video camera is carried around and normal imaging is performed.

1A (a) shows the frequency spectrum of the angular velocity in the pitching direction due to this vibration, and FIG. 1A (b) similarly shows the frequency spectrum of the angular velocity in the yawing direction. As is clear from FIG. 5, the frequency components of camera shake are approximately 0 to 15 Hz in both the pitching and yawing directions, and the levels of each frequency component are approximately equal. In addition, Fig. 6 shows the angular displacement θ of camera shake in the pitching direction with respect to the time axis.
This shows that the amount of camera shake changes from moment to moment. The yawing direction is also the same as the pitching direction.

Here, in order to distinguish between the signals in the pitching direction and the yawing direction, the suffix P is added to the signal in the pitching direction, and the suffix Y is added to the signal in the yawing direction.

In FIG. 1, when vibrations due to camera shake as shown in FIGS. 2 and 3 are transmitted to the camera body 21, the angular velocity sensors 2 and 11 installed and fixed on the zoom lens system 1 are affected by the vibrations in the pitching direction. A signal ωP corresponding to the vibration in the yawing direction and a signal ωY corresponding to the vibration in the yawing direction are output. These output signals ωP and ωY are integrated by the displacement detection circuits 3 and 12, respectively, to generate signals representing the angular displacements θ and ψ (hereinafter referred to as angular displacement signals θP and ψY) as shown in FIG. Ru. These angular velocity signals θP and θY are supplied to actuator drive circuits 4 and 13, respectively.

Here, in the 5 pitching direction, when the entire camera is tilted forward, that is, when the zoom lens system 1 is facing downward, the output signal ωp of the angular velocity sensor 2 becomes positive,
Assuming that when the entire camera is tilted so that the zoom lens system 1 faces upward, this output signal ωP becomes negative polarity.
When the entire camera vibrates in the pitching direction so that the zoom lens system 1 tilts from a horizontal state to a downward state, and then to an upward state, the output signal ωP of the angular velocity sensor 2 is shown as a solid line in FIG. Changes as shown in . Therefore, as shown in the waveform shown by the broken line in FIG. 7, which has the opposite polarity to the output signal ωP of the angular velocity sensor 2, the zoom lens system
By causing the zoom lens system 1 to vibrate in the pitching direction, vibrations caused by camera shake are canceled and the zoom lens system 1 can be kept horizontal. This also applies to the yawing direction. The actuator drive circuits 4 and 13 operate the actuators 7.16 so that the zoom lens system 1 is tilted in the direction opposite to the vibration caused by camera shake.

FIG. 8 is a block diagram showing the entire pitching direction control system, where S is the Laplace operator, angle θP is the angular displacement of the vibration of the entire camera in the pitching direction, and ΔθP is the target angular displacement. . Further, the initial position is used to detect the lens position.

The same applies to the yawing direction.

The present invention enables panning and tilting with the above-described image blur prevention device. Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of a video camera according to the present invention, in which 22 and 23 are position sensors, 24 and 25 are position detection circuits, 26 is a controller 27 is an automatic tilting switch, and 28 is an automatic panning switch. is a switch,
Components corresponding to those in FIG. 1 are given the same reference numerals and redundant explanations will be omitted.

In the figure, the controller 26 is composed of a microcomputer, etc., and in order to prevent image blur due to hand shake, etc., the controller 26 processes the angular signal θP obtained by time-integrating the output signal ωP of the angular velocity sensor 2 with the displacement detection circuit 3. death,
As explained in FIG. 7, a signal that cancels vibrations in the pitching direction is supplied to the actuator drive circuit 4.

Further, the output signal ωP of the angular velocity sensor 11 processes the angle signal θY obtained by time-integrating the displacement detection circuit 12,
Similarly, a signal that cancels vibrations in the yawing direction is supplied to the actuator drive circuit 13.

On the other hand, the worm 6.15 of the actuator 7.16 is provided with position sensors 22 and 23, each consisting of, for example, an absolute encoder.
The rotation angle of the zoom lens system 1 is detected, and the position detection circuits 24 and 25 generate a signal representing the deviation of the zoom lens system 1 from the initial position, that is, the position.

Then, when the automatic tilting switch 27 is turned on,
Controller 26, as shown in FIG.

The output signal of the position detection circuit 24 is taken in to read the position of the zoom lens system 1, thereby sending a signal to the actuator 4, which is operated to rotate the zoom lens system 1 about the pivot shaft 9. At the same time, the output signal of the displacement detection circuit 3 is taken in to determine whether or not the zoom lens system 1 can be mechanically rotated without taking into account the angle of the zoom lens system 1.

The above operations are repeated within the rotatable range set by the user as long as the automatic tilting switch 27 is ON, and tilting is automatically performed. and,
When it is detected from the output signal of the displacement detection circuit 3 that the zoom lens system 1 has rotated to the limit angle, the signal supply to the actuator drive circuit 4 is stopped, and the zoom lens system 1 switches the automatic vanning switch 28. Even when turned ON, the controller 26 takes in the output signals of the position detection circuit 25 and the displacement amount detection circuit 12, and as shown in FIG.
Perform the same operation as shown in FIG. 2 to operate the actuator 16 and perform panning automatically.

In this way, the controller 2G controls the zoom lens system 1.
By constantly adjusting the rotation angle of the hand 61, tilting and panning can be automatically performed within the range set by the user.

〔Effect of the invention〕

As explained above, according to the present invention, it is possible to automatically perform tilting and panning using the 5-image blur prevention device, and it is possible to perform tilting and panning automatically using the 5-image shake prevention device, and it is possible to achieve 1-image quality without increasing the size of the video camera or superimposing the video camera. 1. Improved usability can be achieved.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of a video camera according to the present invention, FIG. 2 is a flowchart showing the operation for tilting of the controller in FIG. 1, and FIG. 3 similarly shows the operation for panning. Flowchart, 4th
Figure 5 is a block diagram showing a specific example of the image stabilization device for a video camera according to the present invention, Figure 5 is a frequency spectrum diagram of vibrations in the pitching and yawing directions of the video camera due to camera shake, and Figure 6 is the time period of this vibration. A diagram showing the displacement of
7 is a diagram showing an example of the output waveform of the angular velocity sensor in FIG. 4, and FIG. 8 is a block diagram showing the entire control system in FIG. 4. DESCRIPTION OF SYMBOLS 1... Zoom lens system, 2... Angular velocity sensor in the pitching direction, 3... Displacement detection circuit, 4... Actuator drive circuit, 7... Actuator, 8...
Gimbal, 9... Pivot axis, 10... Worm wheel, 11... Angular velocity sensor in the yawing direction, 1
2... Displacement detection circuit, 13... Actuator drive circuit, 16... Actuator, 17... Worm wheel, 18... Pivot axis, 19... Image pickup element, 22, 23... Position sensor, 24, 25...Position detection circuit, 26...Controller, 27...Automatic tilting switch, 28...Automatic panning switch. Atsushi (Hisashi) Go Souniri λ4勺Δ (b) Niwa narrow going around in the direction of Yoi〉 (H, <) → Kaotsu plan? Figure diagram

Claims (1)

[Claims] 1. A lens system to which an imaging section of a subject is coupled is supported by a gimbal so as to be rotatable in the pitching direction by a first pivot axis, and the gimbal is supported by a gimbal by a second pivot axis. This allows the lens system to rotate in the yawing direction,
a first angle detection means that is supported and detects a rotation angle of the lens system in the pitching direction; a second angle detection means that detects a rotation angle of the lens system in the yawing direction; and the first angle detection means. a first actuator that rotates the lens system in a pinching direction according to a detection output of the means; a second actuator that rotates the lens system in a yawing direction according to a detection output of the second angle detection means; Detecting an automatic tilting switch, an automatic panning switch, and a rotating position of the lens system in a pinching direction in a video camera equipped with an image stabilization device configured to prevent vibration of the lens system due to hand shake, etc. a first position detecting means for detecting the rotational position of the lens system in the yawing direction; and a controller, the controller detecting the first position when the automatic tilting switch is operated. The detection output of the position detection means is taken in to operate the first actuator, and the detection output of the second position detection means is taken in together with the operation of the automatic tilting switch to operate the second actuator. A video camera characterized in that it is configured to enable tilting and panning. 2. In claim 1, during the tilting or the panning, the controller takes in the detection output of the first or second angle detection means and determines the rotation limit of the lens system in the pinching direction and the yawing direction. A video camera characterized by detecting.