JPH11258651A - Shake correcting device and shake correction camera - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a shake correcting device and a shake correction camera by which shake is highly accurately detected and corrected and a shake correction operation is smoothly executed. SOLUTION: A shake correction lens 5 is held by a lens frame 7. Springs 60, 61 and 62 bias the lens frame 7 so as to be brought into press-contact with steel balls 10a, 11a and 12a. Also, hook parts 7g and 7h are freely movably fitted in a guide shaft 9. Thus, the lens frame 7 is slid on the steel balls 10a, 11a and 12a, and is made movable in a direction orthogonal with an optical axis I. The lens frame 7 is biased by the springs 80, 81 and 82 in the direction rotating by centering the optical axis I. Also, the hook parts 7g and 7h are brought into press-contact with the guide shaft 9, so that backlash between them is eliminated. Thus, the shake correction lens 5 is prevented from being rotated around the optical axis I during shake correction operation, so that the shake is highly accurately corrected.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a camera, a video,
The present invention relates to a shake correction device and a shake correction camera for correcting an image shake caused by a photographer's hand shake in an optical device such as binoculars.

[0002]

2. Description of the Related Art Conventionally, a camera shake detected by an angular velocity sensor is detected, and a camera shake correction optical system which constitutes a part or all of a photographing optical system is driven in a direction to cancel the camera shake. 2. Description of the Related Art A blur correction device that corrects image blur is known.

FIG. 8 is a block diagram showing a single-lens reflex camera equipped with a conventional image stabilizer. The camera shake has a total of six degrees of freedom: three degrees of freedom rotation, consisting of pitching, yawing, and rolling, and three degrees of translation, consisting of movements in the x, y, and z directions. The conventional blur correction device normally corrects blur for two degrees of freedom motion including pitching and yawing motion. The angular velocity sensors 310 and 311 are sensors that detect blurring occurring in the camera. Angular velocity sensor 31
Numeral 0,311 is a piezoelectric vibration type angular velocity sensor for detecting Coriolis force generated by rotation. Angular velocity sensor 3
Reference numeral 10 denotes a pitching detection sensor that detects an angular velocity about the x-axis, and an angular velocity sensor 310 is a yawing detection sensor that detects an angular velocity about the y-axis. The angular velocity sensors 310 and 311 are provided one by one. The angular velocity sensors 310 and 311 output the detected angular velocity signals to the CPUs 330 and 331, respectively.

The CPUs 330 and 331 quantize the input angular velocity signal and calculate target position information for driving the blur correction lens 500 to a target position based on focal length and lens-specific information. CPU33
0, 331 outputs the calculated target position information to the drivers 340, 341.

[0005] Voice coil motors (hereinafter referred to as VCMs) 400 and 410 drive the blur correction lens 500 by an electromagnetic drive system. VCM400 is
The VCM 410 is a motor that drives the blur correction lens 500 in the y-axis direction, and the VCM 410 is a motor that drives the blur correction lens 500 in the x-axis direction. The VCMs 400 and 410 drive the blur correction lens 500 based on the drive signals output by the drivers 340 and 341 respectively.

The position sensors 420 and 430 detect the position of the blur correction lens 500. Position sensor 4
20 detects the position of the blur correction lens 500 in the y-axis direction, and the position sensor 430 detects the position of the blur correction lens 500 in the x-axis direction. The position sensors 420 and 430
Position detection information on the position of the shake correction lens 500 is fed back to the CPUs 330 and 331.

The blur correction lens 500 is a lens that is driven in a plane perpendicular to the optical axis I of the photographing optical system (in the xy plane in the figure) to correct blur. Anti-shake lens 5
00 is held on the inner periphery of the lens frame 700.

[0008]

FIG. 9 is a plan view schematically showing a state in which a position sensor in a conventional shake correction apparatus is installed on an x-axis and a y-axis. FIG. 9A is a diagram in which the states before and after rotation of the shake correction lens 500 are superimposed, and FIG. 9B is a diagram in which the positions of the light spots before and after rotation are superimposed. is there. FIG. 9B
Indicates a member on the position sensor 420 side, and the position sensor 43
The corresponding members on the 0 side are shown in parentheses.

The position sensors 420 and 430 include a light emitting element (LED) (not shown), slit plates 420b and 430b attached to the outer periphery of the lens frame 700, and slits 420 formed in the slit plates 420b and 430b.
c, 430c and light receiving elements (PSDs) 420d, 430d for receiving light passing through the slits 420c, 430c.
And As shown in FIG. 9A, the position sensor 420 passes on the optical axis I and is disposed on an axis (y-axis) perpendicular to the optical axis I.
Are arranged on an axis (x-axis) orthogonal to the y-axis.
When the blur correction lens 500 is at the position shown by the two-dot chain line in the figure, the center O of the blur correction lens 500 coincides with the optical axis I. When the shake correction lens 500 rotates from the position indicated by the two-dot chain line to the position indicated by the solid line in the figure, the center O of the shake correction lens 500 moves to a point O ′ separated by a distance δ. As a result, the slit plates 420b, 430b
The slits 420c and 430c move together with the lens frame 700 to the position shown by the solid line in the figure.

The light receiving elements 420d and 430d are mounted on a fixing member (not shown), and detect the position of the blur correction lens 500 by detecting the centers of gravity G and G 'of the light spot on the light receiving surface. As shown in FIG. 9B, the slits 420c and 430c move from the position indicated by the two-dot chain line to the position indicated by the solid line in the drawing.
The light spot also moves, and the centers of gravity G and G ′ are different before and after the rotation of the shake correction lens 500. As a result, when the position sensors 420 and 430 are arranged on the x-axis and the y-axis, even if the blur correction lens 500 rotates and the center O of the blur correction lens 500 moves, the position sensors 420 and 430 move.
430 can detect the position of the shake correction lens 500.

Japanese Patent Laid-Open Publication No. Hei 10-3101 discloses a blur correcting lens, a lens frame for holding the blur correcting lens,
Two VCMs for driving the blur correction lens in the x-axis direction and the y-axis direction, respectively,
Two position detecting devices for detecting the axial position, three steel balls for movably supporting the lens frame so that the shake correcting lens is driven in a plane perpendicular to the optical axis, A blur correction device is disclosed that includes a guide shaft that movably guides the correction lens and restricts rotation of the blur correction lens around the optical axis. In this blur correction device, the lens frame is supported at three places by three steel balls, but it has been difficult to equalize the frictional force between these steel balls and the lens frame. For this reason, when the shake correction lens is driven, there is a possibility that the shake correction lens will rotate because the magnitudes of the frictional forces at three locations are different. In addition, in a blur correction device disclosed in Japanese Patent Application Laid-Open No. 10-3101, a hook portion is formed on a lens frame in order to prevent rotation of a blur correction lens, and the hook portion is slidably hung on a guide shaft. . However, due to the structure of the shake correction apparatus, the guide shaft needs to be disposed at a position substantially 45 degrees with respect to the x-axis and the y-axis. For this purpose, the position sensor avoids the VCM and the guide axis, and
It had to be placed at a position shifted from the axis.

FIG. 10 is a plan view schematically showing a state in which a position sensor in a conventional shake correction apparatus is installed on an axis parallel to the x-axis and the y-axis. FIG. 10A is a diagram showing the states before and after rotation of the shake correction lens 500 in an overlapping manner, and FIG. 10B is a diagram showing the positions of the light spots before and after the rotation in an overlapping manner. is there. Note that FIG.
(B) shows the members on the position sensor 420 side, and the corresponding members on the position sensor 430 side are shown in parentheses.

[0013] As shown in FIG.
20 is arranged on a virtual axis y ′ parallel to the y axis,
The position sensor 430 is arranged on a virtual axis x ′ parallel to the x-axis. When the blur correction lens 500 is at the position shown by the two-dot chain line in the figure, the center O of the blur correction lens 500 coincides with the optical axis I. When the shake correction lens 500 rotates from the position indicated by the two-dot chain line to the position indicated by the solid line in the figure, the center O of the shake correction lens 500 moves to a point O ′ separated by a distance δ. As shown in FIG.
Since the slits 420c and 430c move from the position shown by the two-dot chain line to the position shown by the solid line in the figure, the light spot also moves, but before and after the rotation of the blur correction lens 500, the centers of gravity G and G 'are changed. Match. For this purpose, the position sensors 420 and 430 are placed on the virtual axis x 'and on the virtual axis y'.
When it is arranged above, the center of gravity of the light spot may not change even if the blur correction lens 500 rotates and the center O of the blur correction lens 500 moves. As a result, the position sensors 420 and 430
Even if 0 is actually at a different position,
00 may be recognized as not moving.

FIG. 11 is a cross-sectional view schematically showing the structure of a voice coil motor in a conventional blur correction device.
FIG. 11A is a diagram illustrating a case where the center of the coil is near the center between the magnetic poles of the permanent magnet. FIG. 11B is a diagram illustrating the center of the coil at a position away from the center between the magnetic poles of the permanent magnet. It is a figure showing when there is. FIG. 11 shows the VCM 40
The members on the 0 side are shown, and the corresponding members on the VCM 410 side are:
Shown in parentheses.

The VCM 400 includes a yoke 400a attached to the protection member 130, a permanent magnet 400b, and a coil 400c disposed between the yoke 400a and the permanent magnet 400b and attached to the outer periphery of the lens frame 500.
Attached to the base member 130, and the permanent magnet 400
and yoke 400d for fixing b. As shown in FIG. 11, between the north pole and the south pole of the permanent magnet 400b, and
A magnetic field is formed between the permanent magnet 400b and the yoke 400a. When a current perpendicular to the direction of the magnetic field flows through the coil 400c, the VCM 400 generates an electromagnetic force that drives the lens frame 700 in the direction indicated by the arrow in the figure.

As shown in FIG. 11, the magnetic circuit of the VCM 400 is not vertically symmetric with respect to the coil 400c, and the lines of magnetic force are not vertically symmetric. As shown in FIG. 11A, when the center of the coil 400c is near the center between the magnetic poles NS, the VCM 400 generates an electromagnetic force in the x-axis direction or the y-axis direction, and generates the optical axis I (z An electromagnetic force in the (axial) direction is also generated. However, the electromagnetic force in the z-axis direction is generated with the same magnitude in the vertical direction, and cancels each other.
Can be driven in the x-axis direction or the y-axis direction.

On the other hand, as shown in FIG. 11B, when the center of the coil 400c is located at a position distant from the center between the magnetic poles NS, the curved portion of the inner line of magnetic force is
overlaps with c. Also in this case, the VCM 400 generates an electromagnetic force in the x-axis direction or the y-axis direction and generates an electromagnetic force in the z-axis direction, but the magnitude of the electromagnetic force in the z-axis direction differs in the vertical direction. . For this reason, the electromagnetic force in the direction of the optical axis I remains without canceling, and the force in the direction of the arrow in FIG. As a result, the lens frame 4
00 and a steel ball that movably supports the lens frame 400, and a load is generated between a hook portion of the lens frame 400 and a guide shaft that movably engages with the hook portion. There is a problem that vibration and driving noise are generated.

An object of the present invention is to provide a blur correction device and a blur correction camera which can detect and correct blur with high accuracy and can smoothly perform a blur correction operation.

[0019]

The present invention solves the above-mentioned problems by the following means. In addition, in order to make it easy to understand, description is given with reference numerals corresponding to the embodiment of the present invention, but the present invention is not limited to this. That is, according to the first aspect of the present invention, a shake correction optical system (5) for correcting shake, a holding member (7) for holding the shake correction optical system, and a driving unit (4) for driving the shake correction optical system are provided.
0, 41) and guide members (9; 70, 71, 72; 10a, 11a, 1) for movably guiding the holding member.
2a) and a play preventing member (80, 81, 82; 90, 9) for preventing play between the holding member and the guide member.
1, 92).

According to a second aspect of the present invention, in the image stabilizing apparatus according to the first aspect, a fixing member (13) for fixing the guide member is provided, and the rattling preventing member is provided on the fixing member (15; 8g). , 8h) and the guide member (8a; 9).
And an image stabilizing device characterized by preventing play between the image and the image.

According to a third aspect of the present invention, in the shake correction apparatus according to the first or second aspect, the guide member is provided with an engaging portion (7g, 7g) of the holding member or the fixing member.
h; 8g, 8h; 15) to be engaged with (9; 8)
a) wherein the play prevention member urges the holding member in a predetermined direction to bring the engagement portion and the engaged portion into press contact with each other, whereby the engagement portion and the engagement portion Urging members (80, 81, 82; 90,
91, 92).

According to a fourth aspect of the present invention, in the shake correction apparatus according to any one of the first to third aspects, the guide member is provided around the optical axis (I) of the shake correction optical system. A rotation restricting portion (9) for restricting rotation, and guide portions (10a, 11a, 12) for movably guiding the blur correction optical system in a direction substantially orthogonal to the optical axis.
a) wherein the rattling preventing member presses the engaging portion of the holding member and the engaged portion of the rotation restricting portion under pressure by urging the holding member around the optical axis. ,And,
An image stabilizing device characterized in that it is a biasing member (90, 91, 92) for bringing the guide portion and the holding member into pressure contact with each other.

According to a fifth aspect of the present invention, in the shake correction apparatus according to any one of the first to third aspects, the guide member restricts rotation of the shake correction optical system around the optical axis. And a guide portion (10a, 11a, 12a) for movably guiding the blur correction optical system in a direction substantially perpendicular to the optical axis. A first urging member (60, 61, 6) for bringing the guide portion and the holding member into pressure contact with each other;
2) and a second urging member (80, 80) that urges the holding member around the optical axis to bring the engaging portion of the holding member into contact with the engaged portion of the rotation restricting portion under pressure. 81,8
2) The blur correction device according to any one of the preceding claims.

According to a sixth aspect of the present invention, in the shake correcting apparatus according to any one of the first to fifth aspects, a position detecting section (42, 43) for detecting a position of the shake correcting optical system. A first driving force generator (40) for driving the blur correction optical system in a first axial direction (y) intersecting with an optical axis, the driving unit intersecting with an optical axis, A second driving force generator (4) that drives the blur correction optical system in a second axis direction (x) substantially orthogonal to the first axis.
1), wherein the position detecting section includes a first position detecting device (42) for detecting a position of the blur correction optical system in the first axis direction, and the blur correction in the second axis direction. A second position detecting device (43) for detecting a position of the optical system, wherein the first position detecting device is disposed on a first virtual axis (y ′) parallel to the first axis. The second position detecting device is a shake correcting device, which is disposed on a second virtual axis (x ′) parallel to the second axis.

According to a seventh aspect of the present invention, a shake correcting optical system (5) for correcting shake, a holding member (7) for holding the shake correcting optical system, and the shake correcting optical system are driven by an electromagnetic force. A driving unit (40, 41), wherein the driving unit is configured to form a magnetic field between the first magnet (40e, 41e) and the first magnet (40b, 41b). A coil (40c, 41c) disposed between the first magnet and the second magnet and provided on the holding member; and a first yoke (40a) attached to the first magnet. , 41
a), and a second yoke (40d, 41d) attached to the second magnet.

According to an eighth aspect of the present invention, there is provided a shake correcting apparatus according to any one of the first to seventh aspects, and a shake detecting section (31) for detecting a shake and outputting a shake detection signal.
And a control unit (33) for controlling the driving of the drive unit based on the shake detection signal.

[0027]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) Hereinafter, a first embodiment of the present invention will be described in more detail with reference to the drawings. First, a case where the shake correction apparatus according to the first embodiment of the present invention is mounted on a single-lens reflex camera will be described as an example. FIG. 1 is a block diagram of a camera system equipped with a shake correction device according to the first embodiment of the present invention. In the following, members or blocks that are the same as the members or blocks shown in FIGS. 8 to 11 are described with corresponding numbers, and detailed descriptions thereof are omitted. In the following, a case will be described as an example where the pitching angular velocity generated in the camera system is detected to correct the blur.

(Interchangeable Lens) The interchangeable lens 1 is a fixed cylinder 1
01, a moving cylinder 102, a first lens group (focusing lens) 3 which moves in the direction of the optical axis I and adjusts a focus for forming an image of a subject on the film surface 25, and a second lens group 4 A blur correction lens (third lens group) 5 that drives in a direction perpendicular to the optical axis I (in the direction of the arrow in the figure) to correct blur, a fourth lens group 6, and a blur correction start switch 30, an angular velocity sensor 31, a filter 32,
Lens-side CPU 33, PWM driver 34, EEP
A ROM 35, a zoom encoder 36, a distance encoder 37, and the like are provided.

The fixed barrel 101 is a member that supports the movable barrel 102 so as to be movable in the direction of the optical axis I. The fixed cylinder 101 is
It is detachably attached to the camera body 2. The fourth lens group 6 is fixed to an inner peripheral portion of the fixed cylinder 101.

The moving barrel 102 includes a first lens group 3, a second lens group
Is a member for performing a zooming operation of moving in the direction of the optical axis I together with the lens group 4 and the blur correction lens 5 to continuously vary the focal length. A first lens group 3, a second lens group 4, a blur correction lens 5, and the like are housed in an inner peripheral portion of the moving barrel 102.

The angular velocity sensor 31 is a sensor for detecting an angular velocity generated in the camera system. Angular velocity sensor 31
Is a pitching detection sensor for detecting an angular velocity around the x-axis, and a yawing detection sensor for detecting an angular velocity around the y-axis is not shown. The angular velocity sensor 31 is connected to the filter 32.

The filter 32 removes a predetermined frequency component from the output signal of the angular velocity sensor 31. The filter 32 cuts a noise component and a DC component included in the high frequency band.

The lens-side CPU 33 calculates the focal length based on the pulse signal output from the zoom encoder 36, calculates the subject distance based on the pulse signal output from the distance encoder 37, Calculates target position information for driving to the position and
This is a central processing unit that controls the drive of 0. Lens side C
PU 33 is an output signal of filter 32 and light receiving element 42
The position detection signal d is converted into a digital signal by a built-in A / D converter, and is taken in. Lens side CPU 33
Calculates target position information based on an output signal of the filter 32, a position detection signal output by the light receiving element 42d, a focal length, a subject distance, and the like. The lens-side CPU 33
The target position information is converted into an analog signal by a built-in D / A converter, and output to the PWM driver 34.

The lens-side CPU 33 includes a shake correction start switch 30 operated by the photographer when starting the shake correction device, a filter 32, a PWM driver 34, and an EE.
The PROM 35, the zoom encoder 36, the distance encoder 37, and the light receiving element 42d are connected. The lens-side CPU 33 communicates with the body-side CP through a lens contact 46 provided between the interchangeable lens 1 and the camera body 2.
It is connected to U45 and can communicate with the body-side CPU 45.

The PWM driver 34 supplies power to the VCM 40 in accordance with the input drive signal (drive voltage). The PWM driver 34 performs current amplification,
A drive current is applied to the coil 40c of the VCM 40.

The EEPROM 35 stores lens data, which are various kinds of unique information relating to the interchangeable lens 1, coefficients for converting a pulse signal output from the distance encoder 37 into physical quantities required for calculation, and the like.

The distance encoder 37 is an encoder for detecting subject distance information on the distance to the subject. The distance measuring encoder 9 detects the position of the photographing optical system, and outputs a pulse signal corresponding to the position to the lens CPU 33.
Output to

The zoom encoder 36 detects the focal length, and outputs a pulse signal corresponding to the focal length value to the lens side CPU 3.
3 is output.

(Camera Body) The camera body 2 is a quick return mirror for distributing a light beam transmitted through the photographing optical system to the body side CPU 45, the release switch 47, the finder screen 20, the finder optical system 21 and the eyepiece 22. And a mirror driving unit 24 for driving the quick return mirror 23.

The body CPU 45 is a central processing unit for controlling the entire camera system. Body side CPU 45
Instructs the lens CPU 33 to start blur correction based on the ON operation of the release switch 47, instructs the lens CPU 33 to stop blur correction based on the OFF operation of the release switch 47, Or drive control. The mirror driving unit 24 and a release switch 47 are connected to the body-side CPU 45.

The release switch 47 detects a half-pressing operation of a release button (not shown), starts a series of photographing preparation operations, and detects a full-pressing operation of the release button to drive the mirror driving unit 24 and the like. A switch for starting a shooting operation.

(Blur Correction Apparatus) FIG. 2 is a sectional view showing a blur correction apparatus according to the first embodiment of the present invention. FIG.
FIG. 3 is a cross-sectional view showing a state cut along a line III-IIIA in FIG. 2. FIG. 4 is a cross-sectional view showing a state cut along the line IV-IV in FIG. FIG. 5 is a cross-sectional view showing a state cut along the line V-VA in FIG. In addition, III- of FIG.
The numbers of members in the cross-sectional view taken along the line IIIB are shown in parentheses in FIG. Also, V-VB of FIG.
The numbers of the members in the cross-sectional views cut along the lines are shown in parentheses in FIG.

The blur correcting lens 5 is a lens that moves in a direction substantially perpendicular to the optical axis I to correct blur. As shown in FIGS. 2 to 5, the shake correction lens 5 is fitted and fixed to the inner peripheral portion of the lens frame 7.

The lens frame 7 is a member for holding the blur correction lens 5. As shown in FIGS. 2 and 5, the lens frame 7 has a slit member 4 disposed in a plane perpendicular to the optical axis I.
2b, 43b and, as shown in FIGS. 3 and 4, the steel ball receiving members 70, 71,
72 and VCMs 40 and 41 as shown in FIGS.
And the coils 40c and 41c. On the outer peripheral portion of the lens frame 7, as shown in FIGS. 3 and 4, spring hooks 7a, 7b, 7c, hooks 7g, 7h, and as shown in FIG. Spring hook portions 7d, 7e and 7f branched from 7c respectively are formed to protrude.

The steel ball receiving members 70, 71, 72 are provided with the optical axis I.
When the lens frame 7 moves in a direction substantially perpendicular to the lens frame 7, the lens frame 7 is movably guided. As shown in FIGS. 3 and 4, the steel ball receiving members 70, 71, 72 are in contact with the steel balls 10a, 11a, 12a for smoothly moving the lens frame 7. The steel ball receiving members 70, 71, 72 are made of a metal having higher hardness than the steel balls 10a, 11a, 12a. Steel ball receiving members 70, 7
1, 72 are end faces 1 of steel ball assembling parts 10, 11, 12
It is preferable that the surface is formed in a planar shape so as to make surface contact with 0b, 11b and 12b.

The springs 60, 61, 62 are connected to the base member 14.
This is an urging member for supporting the lens frame 7 so as to be movable with respect to and for bringing the steel balls 10a, 11a, 12a into contact with the lens frame 7 under pressure. The springs 60, 61, 62
As shown in FIG. 3 and FIG.
a, 7b, and 7c, respectively, and the opposite ends are respectively attached to the spring hooks 14a, 14b, and 14c. In the embodiment of the present invention, the springs 60, 61, 6
The sum of the urging forces of 2 is the blur correction lens 5, the lens frame 7,
Coils 40c, 41c, steel ball receiving members 70, 71, 72
It is preferable to set 1.5 W to 5 W which is 1.5 to 5 times the total weight of the slit plates 42 b and 43 b (hereinafter referred to as W).

The base member 14 includes the steel ball incorporating portion 10,
It is a fixing member for attaching the bearings 11 and 12 and the bearing 15. The base member 14 is formed with spring hooks 14a, 14b and 14c as shown in FIGS. 3 and 4, and spring hooks 14d, 14e and 14f as shown in FIG. As shown in FIGS. 3 to 5, a flange portion 14 g for attaching the protection member 13 is formed on an outer peripheral portion of the base member 14. As shown in FIGS. 3 to 5, the base member 14 includes steel ball incorporating portions 10, 11, 1.
2, a pair of bearing portions 15, yokes 40d and 41d of VCMs 40 and 41, and light receiving elements 4 of position sensors 42 and 43.
2d and 43d are attached.

The protection member 13 is a casing member that protects the drive mechanisms such as the VCMs 40 and 41 together with the base member 700. As shown in FIGS. 3 and 5, the protection member 13 includes yokes 40a and 41a of the VCMs 40 and 41,
The light emitting elements 42a, 43a of the position sensors 42, 43 and the lens frame receiving portions 13a, 13 as shown in FIGS.
b and 13c are attached to the surface on the lens frame 7 side.

Lens frame receiving portions 13a, 13b, 13c
3 and 4 are portions that receive the lens frame 7 and restrict the moving distance of the lens frame 7 within a predetermined range when the lens frame 7 moves leftward in the drawings in FIGS. The lens frame receiving portions 13a, 13b, 13c are arranged at intervals of 120 degrees about the optical axis I. It is preferable that the surfaces of the lens frame receiving portions 13a, 13b, and 13c are formed in a planar shape so as to make surface contact with the lens frame 7. Further, the lens frame receiving portions 13a, 13
The distance between the lens frame 7 and the lens frame 7 b
0, 71, 72 and the end faces 10a, 11a, 12a are relatively separated from each other, the steel ball storage portions 10c, 11c, 12
It is preferable to set the size so that the steel balls 10a, 11a, and 12a do not fall off from c.

The guide shaft 9 is a member for movably guiding the lens frame 7 in a direction substantially perpendicular to the optical axis I and for preventing the blur correction lens 5 from rotating around the optical axis I. is there. The guide shaft 9 is, as shown in FIG.
Both directions of the axial direction and the y-axis direction are arranged in a direction intersecting at a predetermined angle other than a right angle (direction C in the drawing). The guide shaft 9 is adapted to move the hooks 7g, 7h of the lens frame 7 in the direction C in the drawing.
h.

The guide arm 8 is a member for moving the lens frame 7 parallel to the guide direction of the guide shaft 9 (direction C in the figure). As shown in FIG. 2, the guide arm 8 has bearings 8g and 8h formed at both ends thereof.
A guide shaft 9 is rotatably fitted into the bearings 8g and 8h. As shown in FIG. 4, the guide arm 8 has a shaft 8 a formed at the end on the base member 14 side, and the shaft 8 a is rotatably fitted in the bearing 15. As a result, the guide arm 8 is supported by the base member 14 so as to be rotatable in the direction of the arrow in the figure. The rotation of the guide arm 8 causes the lens frame 7 to move along the guide shaft 9.
Can be moved in a direction (direction D in the figure) orthogonal to the guide direction (direction C in the figure). The guide arm 8
Has a pair of shafts 8a fitted into a pair of bearing portions 15, respectively, but in FIG. 4, the illustration of one shaft 8a and the bearing portion 15 is omitted.

The VCMs 40 and 41 are motors for driving the blur correction lens 5 in a direction substantially orthogonal to the optical axis I. The VCM 40 is a motor that generates an electromagnetic force Py in the y-axis direction and drives the lens frame 7 in the y-axis direction, as shown in FIG. The VCM 41 has an electromagnetic force Px in the x-axis direction.
And drives the lens frame 7 in the x-axis direction. The VCMs 40 and 41 have the same structure except that the direction of the electromagnetic force acting on the lens frame 7 is different.
The CM 40 will be described. As shown in FIG. 3, the VCM 40 applies a magnetic field between the yoke 40a attached to the surface of the protection member 13 on the lens frame 7 side, the permanent magnet 40e attached to the yoke 40a, and the permanent magnet 40e. A permanent magnet 40b to be formed, a coil 40c disposed between the permanent magnet 40e and the permanent magnet 40b and mounted on the lens frame 7, and a coil 40c mounted on the surface of the base member 14 on the lens frame 7 side. Yoke 40 to be fixed
d.

FIG. 6 is a sectional view schematically showing the structure of the voice coil motor in the shake correction apparatus according to the first embodiment of the present invention. FIG. 6A is a diagram showing a case where the center of the coil is near the center between the magnetic poles of the permanent magnet. FIG. 6B is a diagram showing the center of the coil at a position away from the center between the magnetic poles of the permanent magnet. It is a figure showing when there is. FIG.
Indicates members on the VCM 40 side, and corresponding members on the VCM 41 side are indicated by parentheses.

As shown in FIG. 6, since the magnetic circuit of the VCM 40 is vertically symmetrical with the coil 40c interposed therebetween, the lines of magnetic force are also vertically symmetrical. As shown in FIG.
When 0c moves, the end of the coil 40c on the right side in FIG.
It overlaps with the curved part of the line of magnetic force. For this purpose, the optical axis I (z
An electromagnetic force in the (axial) direction is generated upward at the upper end of the coil 40c, and an electromagnetic force having the same magnitude as the electromagnetic force in this direction is generated downward at the lower end of the coil 40c. . As a result, the electromagnetic forces in the direction of the optical axis I cancel each other, and only the electromagnetic force in the x-axis direction or the y-axis direction remains. Even if the center of the coil 40c is near the center between the magnetic poles N and S, the magnetic poles Even at a position distant from the center between NS, VCM4
0 generates only an electromagnetic force in the direction of the arrow. VCM40
When current in the direction shown in FIG. 6 flows through the coil 40c,
An electromagnetic force Py for driving the blur correction lens 5 downward along the y-axis direction shown in FIG. 2 is generated, and when a current flows in the reverse direction through the coil 40c, the blur correction lens 5 is driven in the reverse direction (upward). An electromagnetic force Py is generated.

The position sensors 42 and 43 shown in FIGS.
Is a sensor for detecting the position of the blur correction lens 5. The position sensor 42 is a sensor that detects the position of the blur correction lens 5 in the y-axis direction, and the position sensor 43 is a sensor that detects the position of the blur correction lens 5 in the x-axis direction. The position detection sensors 42 and 43 are, as shown in FIG.
At positions shifted with respect to the x-axis and the y-axis, they are respectively disposed facing the VCMs 40 and 41, avoiding the guide shaft 9. The position sensors 42 and 43 have the same structure, and the position sensor 42 will be described below.

As shown in FIG. 5, the position sensor 42 is attached to a light emitting element (LED) 42a attached to the surface of the protective member 13 on the lens frame 7 side, and attached to the surface of the base member 14 on the lens frame 7 side. A light receiving element (PSD) 42d, a slit member 42b disposed between the light emitting element 42a and the light receiving element 42d, and a slit 42c formed in the slit member 42b. Light emitting element 42
The light emitted from a passes through the slit 42c and reaches the light receiving element 42d. When the slit member 42b moves,
The position (light spot) of the light passing through the slit 42c and reaching the light receiving element 42d also moves. When the position of the light changes, the output signal of the light receiving element 42d changes, so that the position of the blur correction lens 5 in the y-axis direction can be detected based on the change of the output signal.

The steel ball assembling parts 10, 11, 12 are parts for holding the steel balls 10a, 11a, 12a and the like. As shown in FIG. 3 and FIG. 4, the steel ball assembling parts 10, 11 and 12 have the same structure.
The description will focus on 0. As shown in FIG. 4, the steel ball assembling portion 10 is attached to a surface of the base member 14 on the lens frame 7 side so as to protrude toward the lens frame 7. The steel ball assembling portion 10 includes a steel ball 10a, an end face 10b, a steel ball storage portion 10c, a compression spring storage portion 10d, a steel ball receiving member 10e, a compression spring 10f, and a screw 10g.

The steel balls 10a, 11a and 12a smoothly move the lens frame 7 in a direction substantially perpendicular to the optical axis I,
And it is a guide member for guiding. Steel ball 10a,
As shown in FIG. 2, 11a and 12a are arranged at intervals of 120 degrees about the optical axis I.

The end face 10b is a guide member for receiving the lens frame 7. The end face 10b contacts and receives the lens frame 7 when the lens frame 7 moves to the left as shown in FIG. It is preferable that the end surface 10b be formed in a planar shape so that the end surface 10b comes into surface contact with the steel ball receiving member 70.

The steel ball storage portion 10c is a portion for storing the steel ball 10a with the steel ball 10a slightly projecting from the end face 10b. The steel ball storage portion 10c is formed between the bottom surface of the compression spring storage portion 10d on the steel ball receiving member 10e side and the end surface 10b. Since the steel ball storage portion 10c has an inner diameter smaller than the inner diameter of the compression spring storage portion 10d,
By the urging force of the compression spring 10f, the compression spring storage 10
The steel ball receiving member 10e does not protrude from inside d.

The compression spring receiving portion 10d is provided with the steel ball receiving member 1
0e and a compression spring 10f for urging the steel ball receiving member 10e toward the lens frame 7 side. A female screw portion 10h that meshes with the screw 10g is formed in the compression spring storage portion 10d. The compression spring storage portion 10d
The steel ball receiving member 10e and the compression spring 10f
h, the steel ball receiving member 10e and the compression spring 10f are fixed by screwing a screw 10g into the female screw portion 10h.

The steel ball receiving member 10e is a guide member that receives the steel ball 10a in a state where the steel ball 10a comes into pressure contact with the steel ball 10a. The steel ball receiving member 10e is made of a metal having a higher hardness than the steel ball 10a, and preferably has a flat surface so as to make point contact with the steel ball 10a.

The compression spring 10f is a member for urging the steel ball receiving member 10e toward the lens frame 7. In the embodiment of the present invention, the sum of the urging forces of the compression springs 10f, 11f, and 12f is preferably set to be at least twice the sum of the urging forces of the springs 60, 61, and 62. For example, when the sum of the urging forces of the springs 60, 61, and 62 is 1.5 W, it is preferable that the sum of the urging forces of the compression springs 10f, 11f, and 12f is set to 3 W or more. As a result, regardless of the posture of the blur correction lens 5, FIGS.
The shake correction lens 5 can be supported at the position shown in FIG.

The springs 80, 81, 82 are urging members for urging the lens frame 7 in a rotational direction about the optical axis I. As shown in FIG. 2, the ends of the springs 80, 81, and 82 are attached to the spring hooks 7d, 7e, and 7f, respectively, and the opposite ends are connected to the spring hooks 14d, 14e, and 14f.
14f. Springs 80, 81, 8
2 urges the lens frame 7 around the optical axis I to bring the hook portions 7g, 7h and the guide shaft 9 shown in FIGS. , And the shaft 8a shown in FIG. In the embodiment of the present invention, the springs 80, 8
1 and 82 are equal, and the spring 8
The sum of the urging forces of 0, 81, 82 is the sum of the springs 60, 61, 6
Preferably, it is smaller than the sum of the two urging forces.

Next, the operation of the shake correction apparatus according to the first embodiment of the present invention will be described. In the state shown in FIG.
Since the hook portions 7g and 7h are hung on the guide shaft 9, the rotation around the optical axis I of the lens frame 7 is restricted. Therefore, the lower electromagnetic force Py along the y-axis direction
Is generated, the lens frame 7 moves the guide shaft 9
Move up and down to the right. As a result, the guide arm 8 shown in FIG. 4 rotates counterclockwise about the axis 8a. When the guide arm 8 rotates, the guide shaft 9 shown in FIG. 2 moves in parallel in a direction (D direction in the figure) orthogonal to the longitudinal direction. The lens frame 7 includes steel balls 10a, 11a, 12
The movement in the direction of the optical axis I is regulated by a. For this reason, the lens frame 7 moves in a plane perpendicular to the optical axis I (in the xy plane) together with the shake correction lens 5, and the shake correction lens 5 corrects the shake. On the other hand, in the state shown in FIG.
When the VCM 41 generates x, the lens frame 7 moves upward and leftward on the guide shaft 9, and the guide shaft 9 moves in parallel in a direction perpendicular to the longitudinal direction (direction D in the drawing). In this manner, the lens frame 7 can move to an arbitrary position in a plane perpendicular to the optical axis I (in the xy plane).

As shown in FIG. 4, the hook portions 7g and 7h are movable in the direction of the optical axis I so that the guide shaft 9g can move slightly.
It is hung on. Therefore, in the state shown in FIGS. 3 and 4, when a rightward impact force acts on the lens frame 7, the lens frame 7 starts moving rightward. As a result, the steel ball receiving members 10e, 11e, 12e, 70, 7
1, 72 receive the impact force intensively at the contact portions with the steel balls 10a, 11a, 12a. Steel ball receiving members 70, 7
1, 72 deflects the compression springs 10f, 11f, 12f while pushing the steel balls 10a, 11a, 12a and the steel ball receiving members 10e, 11e, 12e rightward. Compression spring 1
0f, 11f, and 12f absorb the impact force and reduce the impact force at the contact portions between the steel ball receiving members 10e, 11e, 12e, 70, 71, 72 and the steel balls 10a, 11a, 12a. As a result, no depression (indentation) is formed in these contact portions.

When an impact force exceeding the set value acts on the lens frame 7, the end faces 10b, 11b, 12b come into contact with the steel ball receiving members 70, 71, 72, and the lens frame 7 stops moving. Steel ball receiving members 70, 71, 72 and end faces 10b, 1
Since the surfaces 1b and 12b are in surface contact with each other, no dent (indentation) is formed in the contact portion.

In the state shown in FIGS. 3 and 4, when a leftward impact force acts on the lens frame 7, the lens frame 7 moves leftward against the urging force of the springs 60, 61, 62. As a result, the steel ball receiving members 70, 71, 72 and the steel ball receiving members 10e, 11e, 12e move in directions away from each other. When the impact force is small, the springs 60, 6
When the impact force is large, the lens frame receiving portions 13a, 13b, and 13c come into contact with the lens frame 7, and the lens frame 7 stops moving. Since the lens frame 7 comes into contact with the lens frame receiving portions 13a, 13b, 13c, the steel balls 10a, 11a, 12a do not fall off the steel ball storage portions 10c, 11c, 12c.

The blur correction device according to the first embodiment of the present invention has the following effects. (1) The first embodiment of the present invention includes the springs 80, 81, 8
2 urges the lens frame 7 around the optical axis I. As shown in FIG. 4, when the guide arm 8 rotates, the guide shaft 9 is relatively movable in the optical axis I direction.
It is hung on the hook parts 7g and 7h. The hooks 7g and 7h are hung so as to be slidable on the guide shaft 9. For this purpose, the guide shaft 9 and the hook 7
A small gap (clearance) is formed between g and 7h so that the two can relatively move. Similarly, the guide arm 8 is connected to the guide shaft 9 by the bearing portions 8g and 8h.
Are rotatably supported, and the bearing portion 15 rotatably supports the shaft 8a of the guide arm 8. For this,
A slight gap is formed between the bearings 8g and 8h and the guide shaft 9 and between the bearing 15 and the shaft 8a so that they can relatively rotate.

As shown in FIG. 2, the springs 80, 81, 82
When the lens frame 7 is biased, the lens frame 7 rotates slightly clockwise within the range of the gap to remove the play in the gap. As a result, the lens frame 7
Is driven in a state of being biased around the optical axis I, so that the blur correction lens does not fluctuate in rotation during the blur correction operation, and no error occurs in the detection results of the position sensors 42 and 43. The position can be detected with high accuracy to correct the blur. In addition, the play between the guide shaft 9 and the hooks 7g, 7h can be removed only by attaching the springs 80, 81, 82 to a small space in the shake correction device. For this reason, in order to reduce the play between the guide shaft 9 and the hook portions 7g and 7h, it is not necessary to increase the interval between the hook portions 7g and 7h and lengthen the guide shaft 9, and the shake is eliminated. The correction device can be made compact.

(2) In the first embodiment of the present invention, the VCM
40, 41 permanent magnets 40b, 41b and permanent magnet 40
e, 41e to form a magnetic field, and the coil 40
A magnetic circuit symmetrical with respect to c and 41c is formed. Therefore, the center of the coils 40c and 41c is
VCM 40, 41 even if it is located away from the center between
Generates an electromagnetic force in a direction perpendicular to the optical axis I. As a result, since the VCMs 40 and 41 do not generate electromagnetic force in the optical axis I direction, the steel ball receiving members 70, 71 and 72 and the steel balls 10
a, 11a, and 12a, and driving noise due to the vibration can be suppressed.

Further, since no load is applied between the steel ball receiving members 70, 71, 72 and the steel balls 10a, 11a, 12a, the durability of these members can be improved.
Further, the VCMs 40 and 41 are each provided with a permanent magnet 40.
Since the magnetic heads b and 41b and the permanent magnets 40e and 41e are provided as a pair, the magnetic flux density increases and the generated electromagnetic force also increases. For this reason, the number of turns of the coils 40c and 41c can be reduced to reduce power consumption.

(Second Embodiment) FIG. 7 is a sectional view showing a shake correction apparatus according to a second embodiment of the present invention. In the following, members or blocks that are the same as the members or blocks shown in FIGS. 1 to 6 will be denoted by the same reference numerals, and detailed description will be omitted.

The blur correction device according to the second embodiment of the present invention differs from the first embodiment in that springs 90, 91, 92 are used instead of springs 60, 61, 62 and springs 80, 81, 82.
This is another embodiment provided with. Springs 90, 91, 92
Are urged to rotate the lens frame 7 about the optical axis I, and the lens frame 7 and the steel balls 10a, 11a, 1
2a is an urging member for urging so as to make pressure contact.
As shown in FIG. 7, the ends of the springs 90, 91, 92 are spring-hung portions 7a, 7b, 7c so as to be inclined with respect to the optical axis I.
The other end is attached to a spring hook (not shown) of the base member 14.

The blur correction device according to the second embodiment of the present invention has the effects of the first embodiment, and furthermore, the assembly is easy because the number of springs is reduced, and the number of parts is reduced. A space for installing the member can be secured.

(Other Embodiments) The present invention is not limited to the above-described embodiments, and various modifications or changes can be made as described below. Within range. (1) In the embodiment of the present invention, the springs 80, 81, 82 or the springs 90, 91, 92
Although a total of three springs are arranged at intervals, the number of springs and the intervals are not limited to this, and at least one spring may be used.

(2) In the embodiment of the present invention, the permanent magnet 4
Although the VCMs 40 and 41 including the pair of permanent magnets 0b and 41b and the permanent magnets 40e and 41e are described as an example, only the VCM 40 in the y-axis direction to which gravity is applied is configured by the two permanent magnets 40b and 40e. May be.

(3) In the embodiment of the present invention, the electromagnetic force P
VCM so that the directions of y and Px intersect each other at right angles.
Although the VCM 40 and the VCM 41 are arranged, the angle may be approximately 90 degrees or another angle depending on design convenience. Further, the guide shaft 9 is disposed so as to intersect the x-axis and the y-axis at approximately 45 degrees, but is not limited thereto. Further, the VCMs 40 and 41 have two
More than one may be installed.

(4) The embodiment of the present invention has been described by taking an example in which the interchangeable lens 1 of the single-lens reflex camera is equipped with a shake correcting device. The present invention can also be applied to a case where the device is mounted. Also, the present invention
The present invention is not limited to a still camera, and can be applied to an imaging device such as a digital camera or a video camera, or an optical device such as a binocular or a telescope.

[0080]

As described above in detail, according to the present invention, there is a play between the holding member for holding the shake correcting optical system and the guide member for movably guiding the holding member. Since the prevention is performed by the prevention member, the position of the blur correction optical system can be accurately detected, and the blur can be corrected with high accuracy. Further, according to the present invention, since the coil provided on the holding member is arranged between the first magnet and the second magnet, the blur correction optical system can be driven smoothly and efficiently.

[Brief description of the drawings]

FIG. 1 is a block diagram of a camera system equipped with a shake correction device according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view illustrating the shake correction apparatus according to the first embodiment of the present invention.

FIG. 3 is a sectional view showing a state cut along a line III-IIIA in FIG. 2;

FIG. 4 is a sectional view showing a state cut along line IV-IV in FIG. 2;

FIG. 5 is a sectional view showing a state cut along a line V-VA in FIG. 2;

FIG. 6 is a sectional view schematically showing a structure of a voice coil motor in the shake correction apparatus according to the first embodiment of the present invention.

FIG. 7 is a cross-sectional view illustrating a shake correction apparatus according to a second embodiment of the present invention.

FIG. 8 is a block diagram illustrating a single-lens reflex camera equipped with a conventional shake correction device.

FIG. 9 is a plan view schematically showing a state in which a position sensor in a conventional shake correction apparatus is installed on an x-axis and a y-axis.

FIG. 10 shows a position sensor x in the conventional shake correction apparatus.
It is a top view which shows roughly the state installed on the axis parallel to an axis and a y-axis.

FIG. 11 is a cross-sectional view schematically showing a structure of a voice coil motor in a conventional blur correction device.

[Explanation of symbols]

Reference Signs List 1 interchangeable lens 2 camera body 5 blur correction lens (third lens group) 7 lens frame 7g, 7h hook portion 8 guide arm 8a shaft 8g, 8h bearing portion 9 guide shaft 10, 11, 12 steel ball mounting portion 10a, 11a , 12a Steel ball 14 Base member 15 Bearing part 31 Angular velocity sensor 33 Lens side CPU 40, 41 Voice coil motor (VCM) 40b, 40e, 41b, 41e Magnet 40a, 40d, 41a, 41d Yoke 40c, 41c Coil 42, 43 Position Sensors 70, 71, 72 Steel ball receiving members 60, 61, 62, 80, 81, 82, 90, 91, 9
2 Spring I Optical axis

Claims (8)

[Claims] 1. A blur correcting optical system for correcting blur, a holding member for holding the blur correcting optical system, a driving unit for driving the blur correcting optical system, and a guide member for movably guiding the holding member. And a play preventing member that prevents play between the holding member and the guide member. 2. The blur correction device according to claim 1, further comprising: a fixing member for fixing the guide member, wherein the rattling preventing member prevents a play between the fixing member and the guide member. An image stabilization device, characterized in that: 3. The blur correction device according to claim 1, wherein the guide member includes an engaged portion that engages with an engaging portion of the holding member or the fixing member. The prevention member urges the holding member in a predetermined direction to bring the engaging portion and the engaged portion into pressure contact with each other, thereby causing a play between the engaging portion and the engaged portion. And a biasing member for preventing the vibration. 4. One of claims 1 to 3
In the blur correction device according to Item, the guide member includes: a rotation restricting unit that restricts rotation of the blur correction optical system around the optical axis; and the rotation correction unit controls the blur correction optical system in a direction substantially orthogonal to the optical axis. A guide portion that movably guides the holding member, wherein the rattling preventing member urges the holding member around the optical axis to thereby engage the engaging portion of the holding member and the engaged portion of the rotation restricting portion. And a pressurizing member that presses the guide portion and the holding member in pressurized contact with each other. 5. The method according to claim 1, wherein:
In the blur correction device according to Item, the guide member includes: a rotation restricting unit that restricts rotation of the blur correction optical system around the optical axis; and the rotation correction unit controls the blur correction optical system in a direction substantially orthogonal to the optical axis. A guide portion for movably guiding the guide member, wherein the rattling preventing member includes a first biasing member for bringing the guide portion and the holding member into pressure contact with each other, and biasing the holding member around the optical axis. And a second urging member that presses the engaging portion of the holding member and the engaged portion of the rotation restricting portion. 6. Any one of claims 1 to 5
The blur correction device according to any one of the preceding claims, further comprising: a position detection unit that detects a position of the shake correction optical system, wherein the driving unit drives the shake correction optical system in a first axial direction that intersects an optical axis. A first driving force generator, and a second driving force generator that drives the blur correction optical system in a second axis direction that intersects the optical axis and is substantially orthogonal to the first axis. A first position detection device that detects a position of the shake correction optical system in the first axis direction; and a second position detection device that detects a position of the shake correction optical system in the second axis direction. Wherein the first position detection device is disposed on a first virtual axis parallel to the first axis, and the second position detection device is provided with the second axis. Being arranged on a parallel second virtual axis. Image stabilizer. 7. A blur correction optical system that corrects blur, a holding member that holds the blur correction optical system, and a driving unit that drives the blur correction optical system by using an electromagnetic force. A magnet that forms a magnetic field between the first magnet and the first magnet; and a coil that is disposed between the first magnet and the second magnet and that is provided on the holding member. And a first yoke attached to the first magnet; and a second yoke attached to the second magnet. 8. One of claims 1 to 7
The blur correction device according to the item, a blur detection unit that detects blur and outputs a blur detection signal, and a control unit that drives and controls the driving unit based on the blur detection signal. Camera shake correction.