JP2003057707A - Image blurring correction device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make an image blurring correction device smaller in size. SOLUTION: A pitching moving frame 2 for holding an image blurring correcting lens group 1 is held so as to freely slide in a pitching direction (Y direction), and bearings 2a and 2b are divided into two. A yawing moving frame 4 is held so as to freely slide in a yawing direction (X direction), bearings 4a and 4b are divided into two. An electromagnetic actuator 13y for driving the image blurring correcting lens group 1 in the Y direction is arranged between the bearings 4a and 4b, and an electromagnetic actuator 13x for driving the lens group 1 in the X direction is arranged between bearings 3a and 3b. By having such the constitution, the miniaturization of the image blurring correcting device is attained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image blur correction device mounted on a lens barrel for performing camera shake correction, and more particularly to miniaturization thereof.

[0002]

2. Description of the Related Art In recent years, consumer video cameras have been reduced in size and weight and optical zoom has been increased in magnification, and the usability thereof has been remarkably improved. For this reason, the video camera has become an ordinary video device for general photographers. However, on the other hand, downsizing, weight reduction, and higher magnification of optical zoom have caused video camera users who are not familiar with shooting, to cause the screen to become unstable if camera shake occurs during shooting. . Therefore, in order to reduce such troubles, many video cameras equipped with an image stabilization device have been developed and already commercialized.

Further, a digital still camera for taking a still image has also become widespread, and in this digital still camera, as the resolution becomes higher, the influence of camera shake becomes more noticeable.

As an image stabilization apparatus for this video camera and digital still camera, as described in Japanese Patent Application Laid-Open No. 2001-117129 previously filed by the present inventor, a correction lens group is perpendicular to the optical axis. There is proposed a method of correcting a camera shake by a photographer to obtain a stable image by moving in two different directions. FIG. 6 is an exploded perspective view showing an example of the conventional image blur correction device 45 disclosed in the above publication.

An image blur compensating lens group 31 for compensating for image blur during photographing is fixed to a pitching moving frame 32 which is movable in the Y and X directions in FIG. The pitching moving frame 32 is configured to be slidable in the Y direction via two pitching shafts 33a and 33b by providing a bearing 32a and a rotation stopper 32b on the opposite side. A first electromagnetic actuator 36y is arranged below the pitching movement frame 32. The first electromagnetic actuator 36y includes a first coil 37y attached to the pitching movement frame 32, a magnet 38y attached to the fixed frame 40, and a yoke 39y.

Further, on the right side of the pitching moving frame 32,
The second electromagnetic actuator 36x is arranged. The second electromagnetic actuator 36x includes a second coil 37x attached to the pitching movement frame 32, a magnet 38x attached to a fixed frame 40 attached to the fixed frame 10, and a yoke 39x.

A yawing movement frame 34 for moving the image blur correction lens group 31 in the X direction is attached to the -Z direction of the pitching movement frame 32. The yawing moving frame 34 is provided with fixing portions 34c and 34d for fixing the both ends of the two pitching shafts 33a and 33b that slide on the pitching moving frame 32 described above in the Y direction. Further, the yawing movement frame 4 is configured to be slidable in the X direction via the two yawing shafts 35a and 35b by providing the shaft 35b on the opposite side to the bearing 34a.

The yawing shaft 35a is fixed to a fixed portion 40a (not shown) of a fixed frame 40 provided in the -Z direction of the yawing moving frame 34. Further, the yawing shaft 35b is provided with a rotation stopper 4 provided on the fixed frame 40.
It is slidable by 0b.

Next, the size of the image blur correction device 45 will be described with reference to FIG. This figure is a layout view of the pitching movement frame and the electromagnetic actuator when the image blur correction device shown in FIG. 6 is viewed from the −Z direction. In addition, in order to make the explanation easy to understand, this drawing shows the magnet 38y,
38x and yokes 39y and 39x are omitted in the illustration on the -Z side half. As can be seen from this figure, the distance from the center of the optical axis to the left end of the yoke 39x is X2, and the distance from the center of the optical axis to the lower end of the yoke 39y is Y2.
Becomes Therefore, this distance becomes the image blur correction device 45.
Will be a factor in determining the size of.

[0010]

However, the conventional image blur correction device described above has the following problems.

That is, the demand for miniaturization of video movies and digital still camera main bodies has increased more and more recently, and further miniaturization of a lens barrel having an image stabilization device incorporated in the main body has been demanded.

In the conventional example, as described with reference to FIG. 7, in order to reduce the size of the image blur correction device 45 in the X direction, it is necessary to reduce the distance X2. However, in the conventional example, the portion 41 surrounded by the dotted line in FIG. 7 is a useless space, and in order to reduce the distance X2,
It is difficult to dispose the yoke 39y by moving it to the center side of the optical axis, which is one of the factors that hinder the downsizing of the image blur correction device 45. Similarly, in the Y direction as well, although illustration for the explanation is omitted, it is necessary to reduce the distance Y2.

When fixing both ends of the pitching shaft 33a or the yawing shaft 35a,
Since it is necessary to fix them to the fixed portion 34d of the yawing moving frame 34 and the fixed portion 40a of the fixed frame 40 by adhesion, the assembly becomes complicated.

Therefore, the present invention aims to provide an image blur correction device which is more compact than the conventional image blur correction device and which is simplified in assembly.

[0015]

In order to solve this problem, an image blur correction device according to claim 1 of the present invention comprises a first moving frame that holds an image blur correction lens group, and a first moving frame and a first moving frame. A second moving frame that holds the first moving frame slidably in a first direction orthogonal to the optical axis by the second guide means and the first detent means, and third and fourth guides. Is disposed between the fixed frame that holds the second movable frame slidably in the second direction orthogonal to the optical axis and the third and fourth guide means by the means and the second detent means. A second driving unit for driving the image blur compensating lens group in the first direction and a first driving unit for driving the image blur compensating lens unit in the first direction, and a second unit for driving the image blur compensating lens unit in the second direction. Is provided. With this configuration, it is possible to reduce the size of the image blur correction device and further simplify the assembly.

The image blur correction device according to claim 2 is
The first position detecting means is disposed between the fourth guide means and detects the position of the image blur correcting lens group in the first direction, and is disposed between the first and second guide means. It is characterized in that a second position detecting means for detecting the position of the image blur correcting lens group in the two directions is provided. With this configuration,
It is possible to reduce the number of parts of the image blur correction device and further shorten the optical axis direction.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION An image blur correction device according to an embodiment of the present invention will be described below with reference to FIGS. FIG. 1 is an exploded perspective view of an image blur correction device according to the present embodiment, FIGS. 2A and 2B are schematic diagrams illustrating the configuration of the image blur correction device, and FIG. 3 is shown in FIG. 4 is a diagram showing a cross section of the image blur compensating device, FIG. 4 is a diagram showing the relationship between the displacement amount of the position detecting portion of the image blur compensating device and the magnetic flux density of the magnet, and FIG. It is a block diagram which shows a ware structure.

The image blur compensating lens group 1 for compensating for image blur during photographing is composed of a pitching direction which is the first direction (Y direction) and a yawing direction which is the second direction (X direction) in FIG. It is fixed to the pitching moving frame 2 which is also movable. This pitching moving frame 2 includes bearings 2a, 2
By providing the fixing portion 2c for press-fitting and fixing both ends of the pitching shaft 3c on the opposite side to b, it is possible to slide in the first direction (Y) through the three pitching shafts 3a, 3b, 3c. Has become.

A yawing movement frame 4 for moving the image blur correction lens group 1 in the second direction (X direction) is attached to the -Z direction of the pitching movement frame 2. The yawing moving frame 4 has a fixing portion 4 for fixing one side of the two pitching shafts 3a and 3b for sliding the pitching moving frame 2 described above in the pitching direction (Y direction).
d, 4e and a rotation stopper 4c are provided. Further, the yawing moving frame 4 has three bearings 4a and 4b and three yawing shafts 5a and 5b provided on opposite sides thereof with fixing portions 4c for press-fitting and fixing both ends of the yawing shaft 5c.
It is configured to be slidable in the second direction (X direction) via b and 5c.

The fixed frame 6 provided in the -Z direction of the yawing moving frame 4 is provided with two yawing shafts 5a and 5b for sliding the yawing moving frame 4 described above in the yawing direction (X direction). Fixing part 6 for fixing one side
A rotation stopper 6c is provided on a and 6b and the opposite side.

The electric board 7 is the -Z of the pitching moving frame 2.
Is installed in the direction. On this electric board 7, a first coil 8 for driving the correction lens group 1 in the pitching direction is provided.
y, a second coil 8x for driving in the yawing direction, a hall element 9y for detecting the position of the correction lens group 1 in the pitching direction, and a hall element 9x for detecting the position in the yawing direction are provided. The coils 8y and 8x are
The fine pattern coil is integrally formed on the electric substrate 7.

The magnets 10y and 10x are magnetized in two poles on one side. The magnets 10y and 10x are magnet fixing portions 6y and 6x from the Z direction of the fixing frame 6, respectively.
insert at x. Further, by inserting the first yoke 11 from the -Z direction of the fixed frame, the magnets 10y, 10x and the first yoke 11 are attracted to each other with the fixed frame 6 sandwiched therebetween, so that the fixed frame 6 is positioned and fixed. It
On the other hand, the second yoke 12 is 6d of the fixed frame 6 from the Z direction.
Positioned and fixed to.

The first electromagnetic actuator 13y has a first
Coil 8y, magnet 10y, first yoke 11 and second yoke 12. Similarly, the second electromagnetic actuator 13x includes a first coil 8x.
And a magnet 10x, a first yoke 11 and a second yoke 12. The first electromagnetic actuator 13y constitutes first driving means for driving the pitching moving frame 2 in the pitching direction (Y direction) which is the first direction, and the second electromagnetic actuator 13x moves the pitching moving frame 2 to the second direction. The second driving means is configured to drive in the yawing direction (X direction) which is the direction.

With the above configuration, when an electric current is applied to the first coil 8y of the electric substrate 7, the magnet 10y, the first yoke 11 and the second yoke 12 cause the pitching direction (Y) which is the first direction. Direction) is generated. Similarly, when a current is applied to the second coil 8x of the electric board 7, the magnet 10x and the first yoke 1 are fed.
The first and second yokes 12 generate an electromagnetic force along the yawing direction (X direction) which is the second direction. Thus, by the two electromagnetic actuators 13y and 13x,
The image blur compensating lens group 1 includes X, which is substantially perpendicular to the optical axis Z direction.
It is driven in two directions of Y.

Next, the size of the image blur correction device 15 will be described with reference to FIG. 2A shows the positional relationship between the pitching moving frame 2 and the second actuator 13x, and FIG. 2B shows the positional relationship between the yawing moving frame 4 and the first actuator 13y. The second yoke 12 is not shown for the sake of clarity. Further, the first yoke 11 is also divided into two.

As shown in FIG. 2 (a), the bearings 2a and 2b provided on the pitching moving frame 2 are vertically divided, so that the second actuator 13x can be arranged between them. As a result, the second actuator 13
Since it is possible to bring x closer to the optical axis center direction, the distance X1 from the optical axis center to the left end of the second actuator 13x becomes shorter than the distance X2 shown in the conventional example of FIG.

Therefore, the size of the image blur correction device 15 in the X direction can be reduced. Similarly, FIG.
, The bearings 4a provided on the yawing moving frame 4 are
By dividing 4b into right and left, it becomes possible to arrange the first actuator 13y between them. As a result, it becomes possible to bring the first actuator 13y closer to the optical axis center direction, so the distance Y1 from the optical axis center to the lower end of the first actuator 13y is shorter than the distance Y2 shown in the conventional example. Become. Therefore, the size of the image blur correction device 15 in the Y direction can be reduced.

FIG. 3 shows a cross section A of FIG. 2 (a). The pitching shaft 3a is inserted into the bearing 2a of the pitching moving frame 2 in the direction B from above the fixed portion 4d of the yawing moving frame 4, and one end of the pitching shaft 3a is fixed to the fixed portion 4d. On the other hand, the hole diameter of the bearing 2a of the pitching moving frame 2 is formed to be larger than the hole diameter of the fixed portion 4d, and the pitching shaft 3a and the bearing 2a have a clearance of several microns and a grease or the like. Slide. The grease reservoir 2f also serves to store the grease so that the grease does not come out to other portions. Similarly, the fixed portion 4f of the yawing movement frame 4 is attached to the pitching movement frame 2b.
From below, it is inserted into the pitching moving frame 2 in the C direction, and one end thereof is fixed to the fixed portion 4e.

On the other hand, the hole diameter of the bearing 2b of the pitching moving frame 2 is larger than the hole diameter of the fixed portion 4f, and the pitching shaft 3b and the bearing 2b are greased with a clearance of several microns. And slide through. Further, the grease reservoir 2g serves to store the grease so that the grease does not come out to other portions. The pitching shafts 3a and 3b have been described as shafts having a uniform diameter, but they may be so-called stepped shafts in which the diameters of the fixed portions 4d and 4f are large and the diameters of the sliding portions are small.

Regarding the relationship between the yawing moving frame 4 and the fixed frame 6 described with reference to FIG. 2B, since the relationship between the pitching moving frame 2 and the yawing moving frame described above is the same, the description thereof will be omitted.

Next, the position detectors 14y and 14x for detecting the position of the image blur correcting lens group 1 will be described. 9
Hall elements y and 9x convert the magnetic flux density into an electric signal, and are positioned and fixed to the electric board 7. The detection magnet is the electromagnetic actuator 13y,
13x magnets 10x and 10y are used. Therefore, the Hall elements 9y and 9x and the magnets 10y and 10x
The position detectors 14y and 14x are configured by x. Here, the state of the magnetic flux of the magnets 10x and 10y will be described with reference to FIG.

The horizontal axis of the figure shows the position in the pitching direction (Y direction) and yawing direction (X direction) with the optical axis as the center, and the vertical axis shows the magnetic flux density. Further, the center of the horizontal axis is a boundary portion between the two poles magnetized by the magnets 10x and 10y, and the magnetic flux density is zero at this time. This position is substantially aligned with the center of the optical axis of the image blur correction lens group 1. Hall elements 9y, 9x for magnets 10y, 10x
Moves, the magnetic flux density changes substantially linearly with respect to the change in the displacement amount within the range indicated by the broken line centered on the position where the displacement amount is zero.

Therefore, by detecting the electric signals output from the Hall elements 9y and 9x, it is possible to detect the positions of the image blur correction lens group 1 in the pitching direction (Y direction) and the yawing direction (X direction). Becomes

The image blur correction device 15 constructed in this way
The operation will be described below with reference to FIG.

The image blur acting on the camera incorporating the image blur compensator 15 is detected by the two angular velocity sensors 16 arranged at about 90 °. The output obtained by the angular velocity sensor 18 is integrated over time. Then, it is converted into a camera shake angle and converted into target position information of the image shake correction lens group 1. In order to move the image blur correction lens group 1 according to the target position information, the servo drive circuit 17
The difference between the target position information and the current position information of the image blur correction lens group 1 detected by the position detection units 14y and 14x is calculated, and a signal is transmitted to the electromagnetic actuators 13y and 13x.

The electromagnetic actuators 13y and 13x drive the image blur compensating lens group 1 based on this signal. For driving in the pitching direction Y, the servo drive circuit 17
In response to the command from the electromagnetic actuator 13y, when a current flows through the first coil 7y through a flexible printed cable (not shown), a force acts in the pitching direction (Y direction), which is the first direction, so that the pitching moving frame 2 is moved. Drive in the pitching direction (Y direction).

Further, regarding the driving in the yawing direction (X direction) which is the second direction, the electromagnetic actuator 13x receiving a command from the servo drive circuit 17 supplies a current to the second coil 7x through a flexible printed cable (not shown). When flowing, a force acts in the yawing direction (X direction) to drive the yawing moving frame 4 and the pitching moving frame 2 in the yawing direction (X direction). Therefore, the image blur correction lens group 1 can be arbitrarily moved by the pitching movement frame 2 and the yawing movement frame 4 within a two-dimensional plane orthogonal to the optical axis, so that the image blur caused by camera shake is corrected. It becomes possible.

As described above, according to this embodiment, the electromagnetic actuator 13 is provided between the bearings 2a and 2b of the pitching moving frame 2 and the bearings 4a and 4b of the yawing moving frame 4.
By arranging x and 13y respectively, the distance from the center of the optical axis to the end of the electromagnetic actuator can be shortened, so that the image blur correction device can be downsized as compared with the conventional one.

The pitching shafts 3a, 3b, 3
Since the c and the yawing shafts 5a, 5b, and 5c are press-fitted and fixed from the side, the conventional complicated process of bonding can be omitted, and thus the work efficiency can be improved.

Further, the lengths of all the shafts can be made the same, and the cost can be reduced. Further, the position detection unit 14 also serves as a detection magnet and is arranged at the same position as the electromagnetic actuators 13x and 13y, thereby reducing the number of components and shortening the optical axis direction (Z direction) of the image blur correction device 15. Can be realized.

The image blur correction device 15 according to claim 1 of the present embodiment may have a structure in which a position detecting means using a hall element is provided in another place. Alternatively, instead of the magnetic position detecting means, for example, an optical position detecting means including a light emitting element and a light receiving element may be provided or replaced.

As described above, the camera equipped with the image blur compensating device of the present invention can be made compact and lightweight, and can be a digital still camera or a silver salt camera for taking still images as well as movies for taking moving images. Also in this case, it is possible to reduce the size while introducing an effective image stabilization function.

[0043]

As described above, according to the present invention, the size of the image blur correction device can be reduced by disposing the electromagnetic actuator between the bearings in the image blur correction device equipped with the image blur correction lens. Therefore, it is possible to realize a lens barrel and a camera body that are compatible with miniaturization.

Since the shaft is press-fitted and fixed at the time of assembly, a complicated process such as bonding is not required.
The remarkable effect that the assemblability can be improved is obtained. Furthermore, by using the detection magnet of the position detection means as the magnet of the electromagnetic actuator,
The remarkable effect that the number of parts can be reduced and the image blur correction apparatus can be shortened in the optical axis direction is obtained.

[Brief description of drawings]

FIG. 1 is an exploded perspective view of an image blur correction device according to an embodiment of the present invention.

FIG. 2 is a schematic diagram illustrating the configuration of the same image blur correction apparatus.

FIG. 3 is a diagram showing a cross section of the image blur correction device shown in FIG.

FIG. 4 is a diagram showing a relationship between a displacement amount of a position detection unit and a magnetic flux density of a magnet in the image blur correction device.

FIG. 5 is a block diagram showing a hardware configuration of a camera having the same image blur correction device.

FIG. 6 is an exploded perspective view of a conventional image blur correction device.

FIG. 7 is a schematic diagram illustrating a configuration of a conventional image blur correction device.

[Explanation of symbols]

1 Image blur correction lens group 2 Pitching moving frame 3a, 3b, 3c Pitching shaft 4 Yawing movement frame 5a, 5b, 5c yawing shaft 6 fixed frame 7 Electric board 8y, 8x coil 9y, 9x Hall element 10y, 10x magnet 11 First York 12 Second yoke 13y, 13x electromagnetic actuator 14y, 14x position detector 15 Image blur correction device 16 Angular velocity sensor 17 Servo drive circuit

Claims (3)

[Claims] 1. A first moving frame holding an image blur compensating lens group, first and second guide means, and a first anti-rotation means make the first moving frame orthogonal to the optical axis. The second moving frame held slidably in the first direction, the third and fourth guide means, and the second detent means provide the second moving frame.
Is disposed between the fixed frame that holds the movable frame of the second slide body slidably in the second direction orthogonal to the optical axis and the third and fourth guide means, and the image blur correction is performed in the first direction. A first driving unit that drives the lens unit; and a second driving unit that is arranged between the first and second guide units and that drives the image blur correction lens unit in the second direction. Image blur correction device characterized by. 2. A first position detecting unit which is disposed between the third and fourth guide units and which detects the position of the image blur correcting lens group in the first direction, and the first and the first position detecting units. 2. The image blur correction according to claim 1, further comprising a second position detection unit disposed between two guide units for detecting a position of the image blur correction lens group in the second direction. apparatus. 3. A camera comprising the image blur correction device according to claim 1 or 2.