JPH03138629A - Photographing device - Google Patents

Abstract

PURPOSE:To miniaturize a mechanism itself by disposing a mechanism for eliminating a change in angular moment which occurs around a turning shaft by a moving lens at the acting time of zooming and focusing. CONSTITUTION:In the case that a camera main body is moved in a direction shown by an arrow A in a photographing state, the movement of the camera main body in this case is detected by an angular velocity detector 42b. Blurring in the direction shown by the arrow A is detected by a blurring detection circuit 44 based on the detection output, and an output signal for controlling the blurring in the direction shown by the arrow A is outputted to a driving circuit 46 by a control circuit 45. The circuit 46 actuates a motor so that a photographing lens 1 is moved in a direction reverse to the direction shown by the arrow A, and a worm 9 attached with the outputting shaft of the motor is also rotated. Since the worm 9 is meshed with a worm wheel 17, the worm wheel is rotated in the direction shown by an arrow C. And the photographing lens 1 is moved in the direction reverse to the direction shown by the arrow A, because the worm wheel is integrated with the photographing lens 1. Thus, the occurrence of the blurring is prevented and the mechanism itself is miniaturized.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a photographing device such as a video camera.

[Conventional technology]

Photography equipment has become lighter and more compact, and has become more automated such as automatic focusing, improving its mobility and operability.

These features have made it easier to record video. However, when considering the quality of recorded images, image shaking due to camera shake or the like affects the quality of the images.

Particularly in an image photographed with a high zoom magnification, if the image is shaken, it becomes difficult to see and is not desirable in terms of image quality.

Japanese Patent Laid-Open No. 61-19217 was developed as a photographing device that reduces this image shaking (hereinafter referred to as surface blur) and obtains stable images.
Photographing devices such as those shown in Japanese Patent No. 8-192180 have been proposed. This photographing device includes a rotating means capable of rotating the camera body in a yawing direction and a pitching direction with respect to a hand grip, and a detecting means for detecting the amount of shake of the camera body in each of these rotational directions. The control means corrects the shake of the camera body based on the detection result of the detection means, and when the shake of the camera body is detected,
The camera body is moved in a direction opposite to the direction of the camera shake using a rotating means, thereby correcting the shake of the camera body.

In such a photographing device, since the camera body is moved, the size of the device itself becomes large. Therefore, the weight of the device itself becomes heavy. This poses a problem regarding maneuverability.

In view of this point, an imaging device as shown in Japanese Unexamined Patent Publication No. 1-123576 was proposed. This photographic device differs from the previous example in that it has a holding means that holds the photographic lens and the image sensor as one body, and that this is configured to be able to rotate by one rotation in the yawing direction and the pitching direction with respect to the camera body. The other configurations are almost the same.

[Problem to be solved by the invention]

However, with the above configuration, during the zooming operation of a zoom lens, etc., that is, the amount of time that occurs due to the movement of the variator lens group that changes the zoom magnification and the compensator lens that corrects aberrations that occur as the zoom magnification changes. Changes in the rotational moment generated with respect to the moving axis are not considered. Furthermore, no consideration is given to the change in rotational moment as described above due to movement of the focusing lens accompanying the focusing operation.

In the conventional example, camera shake was corrected by controlling the rotating means to operate, including this change in rotational moment. In a zoom lens with a high magnification, the amount of movement of the variator lens group due to zooming is large, so the change in this rotational moment becomes large. Therefore, the driving force of the drive means for driving the rotation means becomes large. Further, since the variation in rotational moment due to camera shake is also required as the driving force, the driving force becomes even larger. Also, in control, in order to control from a state where the change in rotational moment is small to a state where the change is large, it is necessary to set a wide control range. It is difficult to maintain a large control range and perform stable control.

Although zooming has been described above, the same applies to the movement of the focusing lens accompanying the focusing operation.

Particularly when the focusing lens is the front lens, even if the amount of lens movement is small, the amount of change in rotational torque is large.

This is because the front lens is heavier than a variator lens or the like, and the front lens position is farther from the center of rotation.

[Means for Solving the Problems] In order to solve the above problems, the present invention employs a structure in which the lens body and the image sensor are integrally supported rotatably, and the zooming operation and focusing operation are At times, the structure is such that the moving lens cancels out changes in the rotational moment that occur around the rotational axis. In other words, there is a rotational moment generating means that provides a rotational moment equal to the change in rotational moment that occurs during zooming and focusing operations, and this rotational moment generation means is used for lens movement and slow movement that occur during zooming and focusing operations. It is composed of a means to make it happen.

[Effect]

With the above-described configuration, the present invention cancels out changes in the rotational moment around the rotational axis even if the lens moves due to zooming and focusing operations. Therefore, since the initially set state can be maintained with respect to the rotation axis, it is only necessary to control the variation in rotation moment (rotation torque) due to shake of the camera body.

Therefore, the torque required for the rotation axis of the drive actuator that corrects camera shake in order to move the camera body in the opposite direction to the camera shake is small, and a compact actuator can be used.

Also, in the control, it is sufficient to control only the change in rotational moment due to the shake of the camera body. Therefore, control over a wide dynamic range is not required, making control easier.

〔Example〕

Drawings 1 to 5 regarding a photographing device according to an embodiment of the present invention
This will be explained with reference to the diagram.

Figure 1 is a schematic diagram showing the system configuration for preventing camera shake, Figure 2
The figure is a schematic configuration diagram of the photographing device, and Figure 3 is a diagram showing the main part configuration of a rotation mechanism for preventing camera shake, and is a diagram showing a structure in which the lens body is pivotally supported in a swingable manner relative to the camera body. , 4th
Figure 5 shows a structure for canceling changes in rotational moment caused by lens movement associated with zooming operations.
The figure shows a structure for canceling changes in rotational moment caused by movement of the focusing lens when the focusing lens is the front lens.

The configuration and operation will be explained below with reference to the drawings.

Reference numeral 1 denotes a photographing lens for photographing a copy object to obtain a photographed image; 2 a photographing element section for converting the photographed image by the photographing lens into an electrical signal; 3a and 3b a photographing lens 1 for rotating the photographing lens l in the pitching direction; There are two bearings installed symmetrically with respect to the optical axis of the lens, as shown in Figure 1.
Here, only one side is shown, 4a and 4b are the bearings fitted into this bearing part, 5a is the rotating shaft that enters the bearing 4a, and 6
1 is a holding frame A that fixes the rotating shaft 5a, 7 is a fixed frame that holds the rotating shaft 5b, 8 is a worm wheel provided on the outer periphery of the bearing part 3a, 9 is a worm that meshes with the worm wheel 8, and 10 is a worm attached. The motor is fixed to the holding frame A. 11 is a position detector A for detecting the rotational position of the photographic lens 1; 12a and 12b are rotation shafts in the yawing direction fixedly attached to the holding frame A; 13a;
, 13b is a bearing that enters the rotating shaft, and t4a, 11 is a bearing 13a.

15 is a holding frame B that fixes the bearings 13a and 13b, 16 is a position detector B that detects the rotational position of holding frame A with respect to holding frame B, and 17 is a rotating shaft 12b.
18 is a worm that meshes with the worm wheel 17, and 19 is a motor to which the worm 18 is attached, and is fixed to the holding frame B. 20 is a mounting plate for attaching the holding frame B to the camera body, 21 is a fixing mechanism for fixing the photographing lens when camera shake is not controlled, 22 is a motor for releasing this fixing mechanism, and % is the fixing mechanism 21. A holding plate that holds the motor 22, 24 a variator lens group that changes the zoom magnification, 25 a compensator lens that corrects aberrations caused by movement of the variator lens group, 26 a variator frame that holds the variator lens group, and 27 a fan. a compensator frame that holds the pensator lens; 4, a guide rod 29a that guides the movement of the variator frame compensator frame in the optical axis direction;
29b is a cam follower attached to the variator frame and compensator frame, and 30 is a cam follower 29a.

29 b is a cam can having a cam groove (not shown) into which the cam follower is fitted, 31 is a balancer into which the outer periphery of the cam can is fitted, and 32 a is a balancer 3.
1 in the optical axis direction.
A cam pin is fitted into b (not shown) and fixed to the cam can 30, 33 is a retainer that rotatably holds the cam can 30, the tool is a holding plate, and 35 is a contact piece that engages with a notch provided in the cam can. A notch groove (not shown) is provided on the zoom ring held by the user at a position corresponding to the rotating portion of the contact piece. Next, the structure of the front lens when the focusing lens is located in the front lens will be explained. 36 is the front lens group for focusing, 3
1 is a front lens holder, A is a focus can that holds the front lens holder 37, 39 is a presser plate having a helicoid screw that engages with a helicoid screw provided on the focus can blade, and can be rotated around the outer circumference of the lens. The front lens balancer 41, which moves in the optical axis direction, is a cam follower that is fitted into a cam groove 41b (not shown) of the front lens balancer and fixed to the focus can. Next, the detection of camera shake and the configuration of the control section will be explained. 42a and 42b are angular velocity detectors for detecting speed changes in the rotational angle of the shadow lens l in the yawing and pitching directions; 43 is the position detector 1;
1° 16 is a position detection circuit that detects the position of the photographing lens. 45 is a position detection circuit that detects camera shake from the output of an angular velocity detector. 45 is a position detection circuit that detects camera shake using the output from the blur detection circuit. A control circuit 46 outputs a signal to control the photographing lens 1 to prevent the above-described problems. Reference numeral 46 denotes a drive circuit that drives a motor in response to a control output signal from the control circuit 45.

The operation of the present invention configured as described above will be explained below.

In FIG. 2, it is assumed that the camera body moves in the arrow direction (pitching direction: vertical direction with respect to the subject). At this time, if this movement in the direction of the arrow is not prevented, the photographing lens 1 will also move in the direction of the arrow because the camera body moves in the direction of the arrow even though the subject is not moving. For this reason, the photographic lens l
Because the subject image also moves, the photographed image is blurred. In order to prevent this photographed image from blurring, the photographic lens l should remain stationary relative to the object even if the camera body moves in the incoming direction. In other words, insert the photographic lens l in the opposite direction to the direction in which the camera body enters.
should move relative to the camera body.

Shaking can be similarly prevented when moving in the yawing direction (vertical to the direction of arrow B, in the direction of arrow B in FIG. 3).

The operation of each part to operate in this way will be explained. The pitching direction will be explained.

First, when entering the shooting mode, you perform an operation to activate the function that prevents camera shake. When this operation is performed, the fixation of the photographic lens 1, which was fixed by a fixed lock so that the camera body and the photographic lens 1 move as one, is released.
Enters shooting mode. In the initial state, the photographic lens 1 is set in a balanced state so as not to rotate about the rotation axes 5a and 5b. Assume that the camera body moves in the direction indicated by the arrow in the shooting state. At this time, the movement of the camera body is detected by the angular velocity detector 42b. Based on this detection output, the shake detection circuit detects shake in the direction of the arrow.
The control unit w145 outputs an output signal of the shake detection result.

Based on this output signal, the control circuit 45 outputs an output signal for controlling the shake in the direction of the arrow to the drive circuit w146. Based on this output signal, the drive circuit 46 operates the motor 10 so that the photographing lens 1 moves in the opposite direction to the direction of the arrow. At this time, the worm 9 attached to the output shaft of the motor also rotates. Since the worm 9 is meshed with the worm wheel 8, the worm wheel 8 rotates in the direction of arrow C (shown in FIG. 2).

Since the worm wheel 8 is integrated with the photographic lens 1, the photographic lens 1 moves in the opposite direction to the direction indicated by the arrow, and moves in a direction to prevent blurring. Next, we will discuss how to prevent blur in the pitching direction when the photographer is intentionally shooting in the pitching direction.

Generally, the change in angular velocity of the camera body due to camera shake is different from the change in angular velocity caused by intentionally pitching the camera body. That is, when intentionally pitching, the angular velocity changes slowly in one direction, but the angular velocity change due to shake always changes in direction, not in one direction. Take advantage of the time when this direction changes. That is, it is separated from the blur component by the output signal from the blur detector that is input to the control circuit.

If only the camera shake is corrected, intentional pitching motion will not be possible. In order to accomplish this operation, the position of the photographing lens I is detected by the position detector 11, and only the blurring is corrected while maintaining the position of the photographing lens relative to the holding frame.

The same applies to the yawing direction. The blur correction operation has been described above.

Next, the zooming operation 1 combined heating operation during blur correction will be explained.

When the zoom can 35 is rotated to perform a zooming operation, the cam can engaged with the zoom can also rotates. The cam can has a cam groove C, and a cam follower is fitted into the cam groove nivariator frame and the compensator, and as the cam can rotates, the cam follower moves along the cam groove.

Therefore, the variator frame and the compensator frame are guided by the guide rod and move in the direction of the original axis. Assume that due to this movement, the rotation moment around the rotation axes 5a and 5b changes from the initial state, and acts to rotate the mitral lens l in the direction of arrow A as described above.

On the other hand, the balancer 31 is interposed between the bracket and the cam can, and the cam pin 32a that fits into a cam groove 32b provided in the balancer 31 is attached to the cam can 30. Further, the balancer 31 is designed to prevent rotation so as not to rotate due to the rotation. (not shown) cam, beauty 3
When the cam pin 32a rotates, the cam pin 32a also rotates together with the cam can. Therefore, the balancer 31 moves in the optical axis direction by the cam g32b of the balancer 31 fitted to the cam pin 32a. The balancer 31 moves in the opposite direction to the movements of the variator frame and the compensator frame. Therefore, the movement of the balancer 31 acts to generate a rotational moment in the direction opposite to the direction of the arrow. The cam groove shape of the balancer 31 at this time is such that the rotation moment around the ladle rotating shafts 5a and 5b is equalized at each point during the zooming operation.

Next, the rotation axis 5a in the focusing operation (by the front lens)
, 5b are balanced and the initial state is maintained.

When the focus can 38 is rotated, it moves in the optical axis direction by the helicoid screw. Since the front lens holder holding the front lens group is fixed to the focus can 38, the front lens group moves in the direction of the original axis and performs a focusing operation. The front lens balancer 40 is interposed between the housing and the focus can, and the front lens balancer is provided with a cam groove 41b, into which a cam follower 41a fixed to the focus can is fitted. In addition, the front ball balancer's anti-rotation pin has been installed. Therefore, when the focus can rotates, the front lens balancer moves in the optical axis direction by the cam follower 41 attached to the focus can and the cam groove provided in the front lens balancer. At this time, reverse the movement direction of the front lens group and the front lens balancer.
In addition, the shape of the cam groove of the front ball balancer is determined so as not to cause a change in the rotational moment around the rotating shafts 5a and 5b.

Next, FIG. 6 shows an example where the focusing lens is a part of the mask lens (rear lens).

47 is the mask lens front group, 紽 is the master lens rear group, 49
is the master barrel, 50 is the master lens rear group (focusing lens)
52 is a feed screw formed integrally with the shaft of the motor 54, and a feed screw 5 is provided on the engagement member. The threaded parts are engaged. 53 is a gear attached to the feed screw part, 55 is a balancer gear that meshes with the gear and slides on the outer periphery of the master cylinder, and 56 fits into a cam groove provided on the balancer gear and is attached to the master cylinder. The cam follower 57 is a motor holder for attaching the motor 54 to the master cylinder.

Next, I will explain the operation. When the motor is rotated, the feed screw 52, which is integrated with the motor shaft, rotates. The feed screw meshes with the screw of the retaining member 51, and the retaining member moves in the optical axis direction. Since this engaging member is attached to the movable frame, the focusing operation is performed by moving the mask lens rear group held by the movable frame. Further, a gear is attached to the feed screw, and the gear also rotates together with the feed screw. This gear 53 meshes with a balancer gear 55. The balancer gear 55 is provided with a cam groove, and the cam follower 56 is attached to the master cylinder via this cam groove, so when the balancer gear 55 is rotated by the gear 53, it follows the cam groove of the balancer gear. The balancer gear moves in the direction of the optical axis. At this time, the shape of the cam groove of the balancer gear is set to be opposite to the moving direction of the moving frame, and at the same time, at each point during the movement of the moving frame, a change in the rotational moment around the rotating shafts 5a and 5b is prevented. It's the best.

FIG. 11g7 shows another example of canceling the change in rotational moment caused by the movement of the focusing lens due to the focusing operation shown in FIG. 6.

The wing is a moving frame position detector for detecting the position of the moving frame 50, 5
Reference numeral 9 indicates a magnet having an arc shape and attached to the master tube 49, with the center of the rotation axis of the rotation shaft 5a as the center. The generated coil 61 changes the current flowing through the coil according to the detection signal of the moving frame position, and rotates the rotating shaft 5a,
The rotational moment caused by the movement of the moving frame around 5b'&
This is a coil drive circuit that drives the coil so as to cancel the

The coil is attached to the holding frame.

When the moving frame 50 moves, the rotational moment relative to the rotating shafts 5a and 5b changes. This amount of change differs depending on the position of the moving frame. Therefore, by detecting the position of the moving frame,
Magnet 59 applies a force that cancels out the change in rotational moment. The coil 60 is used and the current flowing through the coil 60 is changed to generate the current. This force generates a rotational moment around the rotating shafts 5a, 5b that is opposite to the rotational moment generated by the movement of the movable frame.

By changing the focusing lens from the front lens to the rear lens, the mechanism for canceling the rotational moment can be made small even if a balancer gear is used, so the weight of the lens body can be saved.

FIG. 8 shows another example of canceling rotational moment fluctuations during zoom operation.

62 is a relay gear that meshes with the zoom gear 66 provided on the zoom can 35, B is a balancer drive gear, and 64 is a relay gear 6.
2 and a gear rotation shaft to which a balance drive gear is attached; 65 is a gear holder that rotatably holds the stab gear rotation shaft and is fixed to the master cylinder 49; 67 has a gear portion that meshes with the balancer drive gear; The balancer is rotatable around the outer periphery of the balancer and slidable in the optical axis direction, and its name is a cam follower attached to the master cylinder 49 via a cam groove provided in the balancer. Next, the operation will be explained.

When the zoom can is rotated for zoom operation, the zoom gear provided on the zoom can 35 also rotates. The movement of the lens accompanying the zooming operation has been described above, so a description thereof will be omitted. Here, we will describe the operation to cancel the change in rotational moment that occurs with the zoom operation.

When the zoom gear field rotates, the relay gear that meshes with the zoom gear also rotates.The relay gear and the balancer drive gear are attached via a rotating shaft so that they rotate as a unit.

Therefore, the balancer drive gear also rotates, and the rotation is transmitted to the balancer 67, which has a gear portion that meshes with the balancer drive gear. The balancer 67 moves in the direction of its original axis while rotating due to a cam groove (not shown) provided therein and a cam follower 684ζ fitted into the cam groove. This movement in the optical axis direction cancels the change in rotational moment that occurs with the zoom operation. The cam groove shape is such that it generates the same rotational moment as the rotational moment change at each zoom position that occurs with zooming, and the directions of the generated rotational moments are opposite to each other and are designed to cancel each other out. . Further, since the balancer 67 is disposed at a position away from the rotation axis, it can be made smaller than the balancer shown in FIG. 4. Furthermore, the external dimensions of the lens body can be smaller than when a balancer is provided in the zoom section, and the lens body can be made smaller.

〔Effect of the invention〕

According to the present invention, since a mechanism is provided that cancels out changes in the rotational moment generated around the rotational axis by the moving lens during zooming and focusing operations, the amount of change in rotational moment due to shake of the camera body is provided. Control only the
It is sufficient to prevent blurring of the photographed image. Therefore, the torque required to operate the drive actuator that corrects camera shake is small, and a small-sized actuator can be used, allowing the mechanism itself to be made smaller.

In addition, in terms of control, it is sufficient to control only the change in rotational moment due to camera shake, and control over a wide dynamic range is not required, which has the effect of simplifying control.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing the configuration of a camera shake prevention system according to an embodiment of the present invention, and FIG. FIG. 7 is a cross-sectional view of the main part structure for canceling the change in rotational moment that occurs with respect to the rotational axis when the rear lens focuses. FIG. 8 is a cross-sectional view of the main part structure showing another embodiment for canceling the change in rotational moment about the rotation axis that occurs during zooming operation. 1...Photographing lens 2...Imitation imager part 3a
, 3b...Bearing portion 5a, 5b *12ae12b・Rotating shaft 6...Holding frame A 7...Fixed frame 8.17...Worm wheel 9.18...Worm 11...Position detection Vessel A
13 a, 13 b...Bearing 15...Holding frame B16...Position detector B 20...Mounting plate 21...Fixing mechanism 26...Variator frame 27...
・Compensator frame 31... Balancer 32... Cam pin 35... Zoom can 37... Front lens holder Ah... Focus can 40... Front lens balancer 41, 56... Cam follower 42a
, 42b... Angular velocity detector 43... Position detection circuit 44... Shake detection circuit 45... Control circuit 46... Drive circuit 48
...Master lens rear group 50...Moving frame 55...
Balancer gear 59... Magnet ω... Coil child 2 anti-45 figure 6 figure ffi'7 figure helmet 4 figure 5 figure Y38 figure

Claims (1)

[Claims] 1. A photographing lens (1) for photographing a subject and obtaining a photographed image;
), an image sensor section (2) that converts an image taken by the photographing lens (1) into an electrical signal, and the photographing lens (1).
Support members (3a, 3b,
4, 5a, 5b, 6, 7, 12a, 12b, 13a, 1
3b, 14a, 14b, 15), a detection means (11, 16, 42a, 42b) for detecting rocking, a control means (45) for controlling the photographic lens 1 by an output signal from the detection means, and In a photographing device having driving means (10, 19, 46) for driving the photographing lens (1) by a control means (45), due to changes in photographing conditions, etc., one of the lenses constituting the photographing lens (1) may Means (31,40 ). 2. The means for generating the rotational moment is a first interlocking means (
35, 30, 32, 62, 64, 65, 63), and first control means (32a, 32b, 68) for controlling means for generating rotational moment by this interlocking means. The imaging device according to item 1. 3. The means for generating the rotational moment is a first interlocking means (38,
41a, 53, 55) and a second control means (41
The imaging device according to claim 1, comprising: a, 41b, 56). 4. a first interlocking means interlocking with the zooming operation;
2. The method according to claim 1, further comprising: a first control means for controlling the interlocking means; a second interlocking means for interlocking with the focusing operation; and a second control means for controlling the second interlocking means. Photography equipment.