JP2021018302A - Image blur correction device, optical device with the same, and driving device - Google Patents

Abstract

To provide an image blur correction device which can be made compact in an optical axis-orthogonal direction, an optical device with the same, and a driving device.SOLUTION: An image blur correction device has: a correction object member which moves relative to a fixed member, in a direction orthogonal to an optical axis; first to third movable members which move relative to the fixed member and first and second movable members through first to third guide members, respectively; and plural drive means which apply driving force to the first to third movable member, respectively. The correction object member is retained by the third movable member, the first to third movable members are coupled to the fixed member and first and second movable members, rotatably on first to third axes of rotation connecting the first to third guide members, and one of the first to third axes of rotation is orthogonal to the other axes of rotation.SELECTED DRAWING: Figure 9

Description

The present invention relates to an image shake correction device, an optical device including the image shake correction device, and a drive device.

Conventionally, in order to prevent image shake due to camera shake that occurs during handheld shooting, the optical elements such as lenses and image sensors are shifted in the direction orthogonal to the optical axis according to the shake condition of the optical device detected by the shake detection means. An image shake correction device having a structure for moving is known. Patent Document 1 discloses a driving device that rotates and moves an optical element not only in a direction orthogonal to an optical axis.

JP-A-2010-204276

Since the shutter unit, batteries, and the like are arranged on a plane including the direction orthogonal to the optical axis of the image sensor inside the image sensor, it is required to miniaturize the image shake correction device in the direction orthogonal to the optical axis. However, in the drive device of Patent Document 1, although the thickness can be reduced in the optical axis direction, the drive source is arranged around the optical element, so that the drive device becomes larger in the direction orthogonal to the optical axis.

An object of the present invention is to provide an image shake correction device capable of miniaturization in the direction orthogonal to the optical axis, an optical device including the image shake correction device, and a drive device.

The image shake correction device as one aspect of the present invention refers to the fixing member, the correction target member that moves in a direction orthogonal to the optical axis with respect to the fixing member, and the fixing member via a plurality of first guide members. A first movable member that moves relative to the first movable member, a second movable member that moves relative to the first movable member via the plurality of second guide members, and a plurality of third guide members. It has a third movable member that moves relative to the second movable member via the above, and a plurality of driving means that each applies a driving force to the first to third movable members, and is corrected. The target member is held by the third movable member, and the first movable member is around the first rotation axis connecting the two first guide members out of the plurality of first guide members with respect to the fixed member. It is rotatably connected, and the second movable member is rotatably connected to the first movable member around a second rotation axis connecting two second guide members out of a plurality of second guide members. The third movable member is rotatably connected to the second movable member around a third rotation axis connecting the two third guide members out of the plurality of third guide members, and the first One of the third rotation axes is orthogonal to the other rotation axis.

According to the present invention, it is possible to provide an image shake correction device capable of miniaturization in the direction orthogonal to the optical axis, an optical device including the image shake correction device, and a drive device.

It is sectional drawing which shows the schematic structure of the image pickup apparatus which comprises the image shake correction apparatus which concerns on embodiment of this invention. It is a perspective view of the image shake correction device. It is a rear view of the image shake correction device. It is a figure which shows the structure which excluded the image sensor, the 2nd and 3rd ultrasonic motors, the driven member, the 2nd and 3rd drive guide members, and the urging spring from the structure of FIG. It is sectional drawing of the line AA'of FIG. It is an exploded perspective view of the image shake correction device. It is a figure which shows the structure which excluded the 1st to 3rd ultrasonic motor from the structure of FIG. It is an exploded perspective view of the image shake correction device. It is sectional drawing of the image shake correction apparatus.

Hereinafter, examples of the present invention will be described in detail with reference to the drawings. In each figure, the same member is given the same reference number, and duplicate description is omitted.

FIG. 1 is a cross-sectional view showing a schematic configuration of an image pickup device (optical device) 8 including an image shake correction device according to an embodiment of the present invention. Specific examples of the image pickup apparatus 8 are a digital camera and a digital video camera. The image pickup apparatus 8 has a lens barrel 1 and a camera body 2. The lens barrel 1 may be integrally configured with the camera body 2 like a compact digital camera, or may be detachably configured with the camera body 2 like a digital single-lens reflex camera. Further, the camera body 2 may be a so-called mirrorless camera having no mirror or prism described later, or may have a configuration without a shutter.

For convenience of explanation, as shown in FIG. 1, the optical axis O direction of the lens barrel 1 is the Z direction, and the two directions orthogonal to each other in the plane orthogonal to the Z direction are the X direction and the Y direction. Further, when the Z direction coincides with the horizontal direction, the X direction and the Y direction are parallel to the horizontal direction and the vertical direction, respectively.

In the following description, the case where the correction target member is the image pickup device 6 will be described, but the present invention is not limited to this. The correction target member may be a lens in the lens barrel 1. In this case, the image shake correction device 7 described later is provided in the lens barrel 1.

An angular velocity sensor and an acceleration sensor for image shake correction are arranged inside the lens barrel 1 and the camera body 2. The lens barrel 1 has a zoom lens group and a focus lens group (not shown). A mirror unit 3, a shutter unit 4, a prism 5, an image sensor 6, and an image shake correction device 7 are arranged inside the camera body 2.

When the image pickup apparatus 8 is in the image pickup ready state, the light flux reflected by the mirror unit 3 is guided to the eyes of the imager through the prism 5. At the time of imaging, the mirror unit 3 is in the mirror lockup state, and the shutter unit 4 performs a shutter operation (exposure operation) at a predetermined speed. At this time, the luminous flux from the subject passing through the lens barrel 1 is imaged as an optical image on the image plane of the image sensor 6. The image pickup element 6 is, for example, a photoelectric conversion device such as a CCD sensor or a CMOS sensor, and converts an optical image into an electric signal by photoelectric conversion.

When an external force such as the movement or vibration of the image sensor is applied to the image pickup device 8 at the time of imaging, the optical image imaged on the image pickup surface of the image sensor 6 is shaken (image shake), and the image quality deteriorates. It may end up. In order to correct (reduce) the image shake, the image shake correction device 7 is driven based on the detection signals of the angular velocity sensor and the acceleration sensor arranged in the lens barrel 1 or the camera body 2, and the image pickup which is the correction target member is performed. The element 6 is moved in a plane orthogonal to the optical axis O.

The plane orthogonal to the optical axis O is a plane that can be considered to be substantially orthogonal to the optical axis O in consideration of the dimensional accuracy and assembly accuracy of various parts in the lens barrel 1 and the camera body 2. It is not necessary to be physically very strictly orthogonal to the optical axis O. That is, in order to correct (reduce) the image shake, the image pickup element 6 which is a correction target member may be moved in a direction orthogonal to the optical axis O.

Hereinafter, the configuration of the image shake correction device 7 will be described. FIG. 2 is a perspective view of the image shake correction device 7. 2 (a) and 2 (b) are a view seen from the subject side (front side) and a view seen from the imager side (back side), respectively. FIG. 3 is a rear view of the image shake correction device 7. FIG. 4 shows the image sensor 6, the second ultrasonic motor 9b, the third ultrasonic motor 9c, the driven member 11, the second drive guide member 13, the third drive guide member 14, and the third drive guide member 14 from the configuration of FIG. It is a figure which shows the structure excluding the urging spring 15. FIG. 5 is a cross-sectional view taken along the line AA'of FIG. FIG. 6 is an exploded perspective view of the image shake correction device 7. FIG. 6A shows a configuration in which the image sensor 6, the driven member 11, and the urging spring 15 are removed from the configuration of FIG. FIG. 6B shows a configuration in which the third ultrasonic motor 9c and the third drive guide member 14 are removed from the configuration of FIG. 6A. FIG. 6C shows a configuration in which the second ultrasonic motor 9b and the second drive guide member 13 are removed from the configuration of FIG. 6B. FIG. 7 shows a configuration in which the first ultrasonic motor 9a, the second ultrasonic motor 9b, and the third ultrasonic motor 9c are excluded from the configuration of FIG. 3, FIG. 7 (a), and FIG. (B) is a perspective view and a rear view of the configuration of FIG. 7, respectively. FIG. 8 is an exploded perspective view of the image shake correction device 7. FIG. 9 is a cross-sectional view of the image shake correction device 7.

First, an ultrasonic motor as an actuator mounted on the image shake correction device 7 will be described with reference to FIG. In the present embodiment, the first to third ultrasonic motors 9a, 9b, and 9c have the same configuration, and the first ultrasonic motor 9a will be described as a representative.

The vibrator 20 is composed of a diaphragm 21 as an elastic body and a piezoelectric element 22. The diaphragm 21 and the piezoelectric element 22 are fixed by an adhesive or the like, and the piezoelectric element 22 excites high-frequency vibration by applying a voltage. The oscillator 20 and the oscillator holding member 23 are fixed by an adhesive or the like. The pressurizing mechanism holding member 24 is fixed to the fixing member 10, the first drive guide member 12, and the second drive guide member 13 with screws (not shown) or the like. The pressurizing mechanism holding member 24 is connected to the vibrator holding member 23 via a roller 26. Through the roller 26, the vibrator holding member 23 and the pressurizing mechanism holding member 24 are connected without play in the driving direction and can move in the pressurizing direction of the pressurizing spring 27.

The friction members 28a, 28b, 28c are provided in the first to third ultrasonic motors 9a, 9b, 9c, respectively, and are fixed to the first to third drive guide members 12, 13, 14 by screws (not shown) or the like. Has been done. The vibrator 20 comes into contact with the friction members 28a (28b, 28c) by the pressing force of the pressure spring 27. The elastic member 25 is arranged between the pressure spring 27 and the vibrator 20. The elastic member 25 prevents direct contact between the pressure spring 27 and the piezoelectric element 22 to prevent damage to the piezoelectric element 22.

When a driving voltage is applied to the piezoelectric element 22 while the vibrator 20 is being pressurized by the pressure spring 27, the frictional force generated by the elliptical motion generated in the vibrator 20 is used as the driving force of the friction member 28a (28b). , 28c). As a result, the first to third drive guide members 12, 13, 14 that hold the friction members 28a, 28b, 28c can move in a predetermined direction. That is, the first to third drive guide members 12, 13 and 14, respectively, are given driving force from the first to third ultrasonic motors 9a, 9b and 9c, respectively, so that they are relative to the fixed member 10. Move to.

In the present embodiment, for the sake of simplicity, the first to third ultrasonic motors 9a, 9b, and 9c have the same configuration, but may have different configurations. Further, in the present embodiment, the ultrasonic motor is used as the actuator configured in the image shake correction device 7, but an actuator that operates by another principle such as VCM (voice coil motor) may be used.

Next, the configuration of the image shake correction device 7 will be described. The fixing member 10 is fixed to the camera body 2 by a screw or the like (not shown). The first ultrasonic motor 9a is fixed to the fixing member 10 by a screw or the like (not shown). In the present embodiment, the first ultrasonic motor 9a generates a driving force in the X direction. The friction member 28a is fixed to the first drive guide member (first movable member) 12 and moves integrally with the first drive guide member 12 by the driving force of the first ultrasonic motor 9a.

A plurality of (two in this embodiment) balls (first guide member) 16b are sandwiched between the fixing member 10 and the first drive guide member 12. The two balls 16b are fitted into the rolling groove 10X provided in the fixing member 10 and the rolling groove 12X provided in the first drive guide member 12. The pressing force of the pressure spring 27 of the first ultrasonic motor 9a is applied to the friction member 28a on the first drive guide member 12. There are two pressure points N1 of the pressure spring 27 shown in FIG. 7 (b) in the direction of the rotation axis (first rotation axis) I connecting the two balls 16b shown in FIG. 6 (c). Located in the area between the balls 16b. The pressing force of the pressure spring 27 connects the fixing member 10 and the first drive guide member 12.

The first drive guide member 12 is rotatably connected to the fixing member 10 around a rotation axis I connecting the two balls 16b. The rolling grooves 10X and 12X are formed along the direction of the driving force (X direction) by the first ultrasonic motor 9a. The first drive guide member 12 is guided by the rolling grooves 10X and 12X and the two balls 16c so as to move relative to the fixing member 10 in the X direction. By rolling the two balls 16b between the fixing member 10 and the first drive guide member 12, the first drive guide member 12 efficiently moves relative to the fixing member 10 in the X direction. Can be done. Further, the rolling grooves 10X and 12X regulate the first drive guide member 12 so as not to move relative to the fixing member 10 in the Y direction.

The first drive guide member 12 holds the second ultrasonic motor 9b. The second ultrasonic motor 9b is provided so that the longitudinal direction is substantially orthogonal to the longitudinal direction (X direction) of the first ultrasonic motor 9a. The friction member 28b is fixed to the second drive guide member (second movable member) 13 and moves integrally with the second drive guide member 13 by the driving force of the second ultrasonic motor 9b.

A plurality of (two in this embodiment) balls (second guide member) 16c are sandwiched between the first drive guide member 12 and the second drive guide member 13. The two balls 16c are fitted into the rolling groove 12Y provided in the first drive guide member 12 and the rolling groove 13Y provided in the second drive guide member 13. The pressing force of the pressure spring 27 of the second ultrasonic motor 9b is applied to the friction member 28b on the second drive guide member 13. The pressure spring 27 has two pressure points N2 shown in FIG. 7 (b) in the direction of the rotation axis (second rotation axis) J connecting the two balls 16c shown in FIG. 6 (b). Located in the area between the balls 16c. The pressing force of the pressure spring 27 connects the first drive guide member 12 and the second drive guide member 13.

The second drive guide member 13 is rotatably connected to the first drive guide member 12 around a rotation axis J connecting the two balls 16c. The rolling grooves 12Y and 13Y are formed along the direction of the driving force (Y direction) by the second ultrasonic motor 9b. The second drive guide member 13 is guided by the rolling grooves 12Y and 13Y and the two balls 16c so as to move relative to the first drive guide member 12 in the Y direction. By rolling the two balls 16c between the first drive guide member 12 and the second drive guide member 13, the second drive guide member 13 is more efficient than the first drive guide member 12. It can move relatively in the Y direction. Further, the rolling grooves 12Y and 13Y are regulated so that the second drive guide member 13 does not move relative to the first drive guide member 12 in the X direction.

The second drive guide member 13 holds the third ultrasonic motor 9c. The longitudinal direction of the third ultrasonic motor 9c is substantially orthogonal to the longitudinal direction (X direction) of the first ultrasonic motor 9a (approximately parallel to the longitudinal direction (Y direction) of the second ultrasonic motor 9b). ) Is provided.
The friction member 28c is fixed to the third drive guide member 14 and moves integrally with the third drive guide member 14 by the drive force of the third ultrasonic motor 9c.

A plurality of (two in this embodiment) balls (third guide member) 16d are sandwiched between the second drive guide member 13 and the third drive guide member 14. The two balls 16d are fitted into the rolling groove 13R provided in the second drive guide member 13 and the rolling groove 14R provided in the third drive guide member 14. The pressing force of the pressure spring 27 of the third ultrasonic motor 9c is applied to the friction member 28c on the third drive guide member 14. The pressure spring 27 has two pressure points N3 shown in FIG. 7 (b) in the direction of the rotation axis (third rotation axis) K connecting the two balls 16d shown in FIG. 6 (a). Located in the area between the balls 16d. The pressing force of the pressure spring 27 connects the second drive guide member 13 and the third drive guide member 14.

The third drive guide member 14 is rotatably connected to the second drive guide member 13 around a rotation axis K connecting the two balls 16d. The rolling grooves 13R and 14R are formed in an arc shape along an arc M centered on a point L at the substantially center of the image pickup device 6 shown in FIG. 7B. The third drive guide member 14 is guided by the rolling grooves 13R and 14R and the two balls 16d so as to rotate with respect to the second drive guide member 13 about the point L. By rolling the two balls 16d between the second drive guide member 13 and the third drive guide member 14, the third drive guide member 14 is more efficient than the second drive guide member 13. It can rotate and move well.

In the present embodiment, the center of the rotational movement of the third drive guide member 14 is the center of the image sensor 6, but a position deviated from the center of the image sensor 6 may be the center of the rotational movement. Further, in the present embodiment, the rolling grooves 13R and 14R are formed in an arc shape, but may be formed in a straight line so as to be in contact with the arc M.

The driven member 11 is in contact with the fixing member 10 via three balls (rolling members) 16a. An urging spring 15 is provided between the fixing member 10 and the driven member 11. The urging spring 15 applies an urging force to the fixing member 10 and the driven member 11. The rolling portion provided on the fixing member 10 and the driven member 11 is a flat surface and does not regulate the driving direction. The driven member 11 and the third drive guide member 14 are fixed by screws or the like (not shown) to form a third movable member.

As described above, the fixing member 10 and the first drive guide member 12, the first drive guide member 12 and the second drive guide member 13, and the second drive guide member 13 and the third drive guide member 14 are They are connected via two balls 16b, 16c, 16d, respectively. Further, the first to third drive guide members 12, 13 and 14, respectively, rotate around the rotation axes I, J and K with respect to the fixing member 10, the first drive guide member 12 and the second drive guide member 13, respectively. It is rotatably connected. The rotation axis I is not parallel to the rotation axes J and K but is substantially orthogonal to the rotation axes J and K. Further, the driven member 11 is fixed to the third drive guide member 14.

With such a configuration, as shown in FIG. 9, the driven member 11 can rotate around the rotation axes I, J, and K with respect to the fixing member 10. That is, the driven member 11 can move relative to the fixed member 10 with three degrees of freedom.

When the fixing member 10 and the first to third drive guide members 12, 13 and 14 are connected without a degree of freedom, the driven member 11 causes a dimensional error or an assembly error of each member. It is not possible to stably contact the fixing member 10, and floating occurs. In the present embodiment, by giving the driven member 11 three degrees of freedom, the driven member 11 passes through the ball 16a without causing floating even when a dimensional error or an assembly error of each member occurs. It is possible to stably contact the fixing member 10.

In the present embodiment, when the first ultrasonic motor 9a is driven, the first drive guide member 12 and the second ultrasonic motor 9b move integrally with the fixing member 10. Further, when the second ultrasonic motor 9b is driven, the second drive guide member 13 and the third ultrasonic motor 9c move integrally with the first drive guide member 12. Further, when the third ultrasonic motor 9c is driven, the third drive guide member 14 and the driven member 11 move integrally with the second drive guide member 13. As a result, the driven member 11 and the image sensor 6 fixed on the driven member 11 are translated into two with respect to the fixed member 10 by the driving force of the first to third ultrasonic motors 9a, 9b, 9c. Relative movement in the direction (X direction and Y direction) and the rotation direction around the point L becomes possible.

As described above, in the present embodiment, the first to third ultrasonic motors 9a, 9b, 9c, and the first to third drive guide members are relative to the driven member 11 that holds the image pickup element 6. 12, 13 and 14 are arranged so as to be stacked in the Z direction. As a result, the image shake correction device 7 can be miniaturized in the direction orthogonal to the optical axis (XY plane direction).

Although the preferred embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and various modifications and modifications can be made within the scope of the gist thereof.

In the present embodiment, the configuration in which the relative movement in the two translational directions (X direction and the Y direction) and the rotation direction is possible has been described, but even in the configuration in which the relative movement is possible only in the two translational directions intersecting each other. Good. Assuming that the first drive guide member 12 is the first movable unit and the image sensor 6, the driven member 11, the second drive guide member 13, and the third drive guide member 14 are the second movable units, the first movable unit is It can move in the first direction, and the second movable unit can move in the second direction.

Further, in the present embodiment, an example of moving the correction target member used for image shake correction as the drive target member has been described, but the present invention can also be applied to a drive device using a microscope stage or the like as the drive target member.

6 Image sensor (correction target member)
7 Image runout correction devices 9a, 9b, 9c First to third ultrasonic motors (plural drive means)
10 Fixing member 11 Driven member (third movable member)
12 First drive guide member (first movable member)
13 Second drive guide member (second movable member)
14 Third drive guide member (third movable member)
16b ball (first guide member)
16c ball (second guide member)
16d ball (third guide member)

Claims (7)

Fixing member and
A correction target member that moves in a direction orthogonal to the optical axis with respect to the fixed member,
A first movable member that moves relative to the fixing member via the plurality of first guide members,
A second movable member that moves relative to the first movable member via the plurality of second guide members,
A third movable member that moves relative to the second movable member via the plurality of third guide members,
Each has a plurality of driving means for applying a driving force to the first to third movable members.
The correction target member is held by the third movable member, and is held.
The first movable member is rotatably connected to the fixing member around a first rotation axis connecting two first guide members out of the plurality of first guide members.
The second movable member is rotatably connected to the first movable member around a second rotation axis connecting two second guide members out of the plurality of second guide members.
The third movable member is rotatably connected to the second movable member around a third rotation axis connecting two third guide members out of the plurality of third guide members.
An image shake correction device, characterized in that any one of the first to third rotation axes is orthogonal to the other rotation axis. The plurality of first guide members are two first guide members.
The plurality of second guide members are two second guide members.
The image shake correction device according to claim 1, wherein the plurality of third guide members are two third guide members. At least one of the plurality of driving means is an ultrasonic motor composed of an oscillator having a piezoelectric element and a friction member pressurized via the oscillator.
The pressing force applied to the friction member via the vibrator is a region between the two first guide portions in the direction of the first rotation axis, the direction of the second rotation axis. It is characterized in that it is given to any region of the region between the two second guide portions and the region between the two third guide portions in the direction of the third rotation axis. The image shake correction device according to claim 1 or 2. The image runout according to any one of claims 1 to 3, wherein the correction target member, the fixing member, and the first to third movable members are arranged along the optical axis. Compensator. An optical device comprising the image shake correction device according to any one of claims 1 to 4. Fixing member and
Drive target member and
A first movable unit that is moved in a first direction with respect to the fixing member by the first driving means,
It has a second movable unit that includes the drive target member and is moved by a second drive means in a second direction that intersects the first direction with respect to the first movable unit.
The first movable unit is rotatably connected to the fixing member around the first rotation axis.
The driving device is characterized in that the second movable unit is rotatably connected to the first movable member around a second rotation axis orthogonal to the first rotation axis. The first axis of rotation is parallel to the first direction and
The driving device according to claim 6, wherein the second rotating shaft is parallel to the second direction.