JP2013109005A - Imaging apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an imaging apparatus that is slim in a collapsed state and free from interference of an electromagnetic linear motor and an image stabilizing device with each other.SOLUTION: An imaging apparatus includes a lens barrel 1 that holds a taking lens system composed of a plurality of lenses 21-24 including a focusing lens 24, an imaging device 110 that receives an optical image formed through the taking lens system to generate image data, and an image stabilizing device 105 that performs an image stabilizing operation by shifting the imaging device 110 in a plane parallel to a light receiving surface of the imaging device. The lens barrel 1 contains an electromagnetic linear motor 18 serving as a focus driving unit that drives the focusing lens 24 forward/backward along the optical axis. A portion of the electromagnetic linear motor 18 is located in the image stabilizing device 105 in such a way as not to interfere with the image stabilizing device 105.

Description

The present invention relates to an imaging apparatus such as an electronic camera.

2. Description of the Related Art In recent years, image pickup apparatuses that take an image of a subject using an image pickup device such as a CCD or a CMOS sensor have become widespread. In these imaging apparatuses, a movable lens frame, in particular, a lens frame that holds a focusing lens, is driven forward and backward in the optical axis direction, a motor, a lead screw that is rotationally driven by the motor, and a nut member that engages with the lead screw. Is used to move the movable lens frame together with the nut member so that the movable lens frame moves forward and backward by VCM driving (see, for example, Patent Documents 1 and 2).

For example, Patent Document 1 describes an imaging device having a lens barrel provided with a bent imaging optical system. In this imaging apparatus, the second group, the fourth group, and the fifth group lens among the five-group lens groups are movable lenses. Of these, the fifth group lens that performs focusing is supported by a fifth group lens frame that is formed integrally with the sleeve. The sleeve has a female screw member that engages with a lead screw that extends in the optical axis direction rotated by a motor disposed on the imaging element side, and a guide shaft that extends in the optical axis direction penetrates slidably. doing. Thereby, the fifth group lens is driven forward and backward in the optical axis direction by rotating the motor.

Further, according to Patent Document 2, the imaging apparatus moves the movable lens in the optical axis direction by an actuator such as a voice coil motor. In this imaging apparatus, the focus base member 6 is fixed (coupled) to the imaging base plate 9. The focus base member 6 includes a yoke 6.
1, 62 and the magnet 63 are fixed. An air-core coil 41 having a rectangular tube shape is fixed to the fourth holding frame 4. The air core portion of the coil 41 is open toward the optical axis direction.

JP 2009-133944 A JP 2010-72061 A

Incidentally, many digital cameras have an image blur correction mechanism for correcting image blur due to hand movement or the like during shooting. As an image blur correction method, optical image blur correction in which correction is performed by moving an image sensor is known. In order to perform this optical image blur correction,
An image blur correction device for moving the image sensor is provided, and the image sensor is mounted on the image blur correction device.

However, the focus drive unit that drives the focusing lens interferes with the image blur correction device, which limits the size reduction of the imaging device. For example, in the imaging apparatus of Patent Document 1, a lead screw of a focus drive unit and a motor disposed under the lead screw project to the imaging element side. For this reason, when an image blur correction device is provided, the motor must be disposed outside the image sensor when viewed in the optical axis direction so that the motor and the image blur correction device do not interfere with each other. Will become bigger.

Further, in the imaging device described in Patent Document 2, a lens barrel that can be expanded and contracted with a base member interposed therebetween and an image blur correction device are fixedly arranged. The focusing motor and the guide shaft are fixed at the outer peripheral portion of the fixed frame of the lens barrel, avoiding a position where the focusing motor and the guide shaft interfere with the image blur correction device on the back side. Even with this configuration, the diameter of the lens barrel cannot be reduced. In addition, since the motor and guide shaft are provided on the outer periphery of the fixed frame, there is room for improvement in that if the strobe or tripod screw is further arranged, the device must be made larger in order to secure a space for the arrangement. There is.

Accordingly, an object of the present invention, which has been made paying attention to these points, is to provide a small-sized imaging apparatus without interference between the focus driving unit and the image blur correction apparatus.

The invention of an imaging apparatus according to claim 1 that achieves the above object is as follows:
A lens barrel that holds an imaging lens system including a plurality of lenses including a focusing lens, an imaging element that receives an optical image formed through the imaging lens system and generates image data, and the imaging element An image blur correction device that performs an image blur correction operation by displacing the lens in a plane parallel to the light receiving surface, and the lens barrel includes the focusing lens (including a wobbling lens) along the optical axis. An electromagnetic linear motor that is driven forward and backward is included, and a part of the electromagnetic linear motor enters the image blur correction device so as not to interfere with the image blur correction device.

“Intrusion” as used herein means “for example, the position behind the image blur correction device (image side) so that the rear end of the electromagnetic linear motor or the guide shaft support portion on the optical axis does not interfere. Or a notch recess may be formed in a part of the movable portion in the image blur correction apparatus.
“Through” means that the image blur correction apparatus has an opening that penetrates in the optical axis direction, and a part of the focus drive unit is at least partially inserted into the opening. Means. That is, a part of the electromagnetic linear motor does not necessarily extend to the rear of the image blur correction device.

The invention according to claim 2 is the imaging apparatus according to claim 1,
A part of the electromagnetic linear motor penetrates the image blur correction device.

The invention according to claim 3 is the imaging apparatus according to claim 1 or 2,
The image blur correction device includes a base member to which the lens barrel is fixed, a slider supported by the base member so as to be movable in a first direction orthogonal to the optical axis, and the optical axis and the slider by the slider. A sensor holding frame that holds the imaging element supported so as to be movable in a second direction orthogonal to the first direction, and a part of the electromagnetic linear motor is seen in the optical axis direction. In the slider region, the sensor holding frame penetrates outside the moving region.
According to a fourth aspect of the present invention, in the imaging device according to the first or second aspect, the cross-sectional area of the main focus guide shaft is larger than the cross-sectional area of the sub-focus guide shaft.
According to a fifth aspect of the present invention, when the electromagnetic linear motor is viewed from the object side, the distance between the drive action line where the magnetic flux of the drive coil and the magnetic circuit intersect with the main focus guide axis is the distance between the drive action line and the sub focus guide axis. It is characterized by being shorter than the distance.

According to the present invention, the lens barrel includes a focusing lens and an electromagnetic linear motor that drives the focusing lens to move back and forth along the optical axis, and a part of the electromagnetic linear motor includes:
Since the image blur correction apparatus enters the image blur correction apparatus so as not to interfere with the image blur correction apparatus, the electromagnetic linear motor and the image blur correction apparatus do not interfere with each other, and a thin imaging device can be provided when retracted. .

It is a disassembled perspective view which shows the structure of the principal part of the imaging unit containing the lens-barrel and sensor unit which comprise the imaging device which concerns on one embodiment of this invention. It is sectional drawing in the retracted state of the imaging unit shown in FIG. It is sectional drawing in the wide position of the imaging unit shown in FIG. It is sectional drawing in the tele position of the imaging unit shown in FIG. FIG. 2 is a cross-sectional view of a fourth group lens, a fourth group frame, and a focus drive unit of the imaging unit shown in FIG. 1. It is a rear view of the imaging unit shown in FIG. FIG. 6 is a rear view of a fourth group lens, a fourth group frame, and an electromagnetic linear motor of an imaging unit according to a modification of the present invention. It is sectional drawing of the 4th group lens of the imaging unit which concerns on the modification of this invention, a 4th group frame, and an electromagnetic linear motor. It is sectional drawing of the 4th group lens of the imaging unit which concerns on the modification of this invention, a 4th group lens frame, a focus guide axis | shaft, and a subfocus guide axis | shaft. It is sectional drawing of the 4th group lens of the imaging unit which concerns on the modification of this invention, a 4th group lens frame, and an electromagnetic linear motor.

Hereinafter, an imaging apparatus according to an embodiment of the present invention will be described with reference to the drawings.

In the description of the present embodiment, the optical axis (imaging optical axis) of the imaging optical system in the lens barrel is represented by the symbol O. In the direction along the optical axis O (photographing optical axis direction), the subject side (object side) is defined as the front, and the direction in which each frame member in the lens barrel is directed forward is referred to as the feeding direction. On the other hand, in the direction along the optical axis O, the imaging side (image side) is the rear, and the direction in which each frame member heads backward is referred to as the retraction direction. Moreover, the rotation direction of each structural member in a lens barrel shall be represented by the rotation direction seen from the front side.

The imaging apparatus according to the present embodiment uses a telescopic optical system, that is, a lens barrel. This lens barrel extends in a direction along the optical axis O, extends toward the front of the housing of the image pickup apparatus, and protrudes to perform a shooting operation, that is, in a use state in a mode waiting for the shooting operation. There are a shooting standby state (shooting enabled state) and a non-use state in which the lens barrel is not used for the shooting operation because it is stored in the housing of the imaging device by being shortened from the state of extending in the direction along the optical axis O. When the entire length of the lens barrel can be extended and retracted between the retracted state and it is in a shootable state, a plurality of frames are provided between the short focus position (wide end) and the long focus position (tele end). It has a telescopic mechanism that enables a zooming operation (zooming) by extending or retracting a member.

First, the configuration of the lens barrel will be described with reference to FIGS.

The lens barrel 1 includes a fixed frame 2 fixed to the base member 101 of the sensor unit 100,
The optical axis O is supported by the fixed frame 2 and is driven to rotate during zooming or retraction.
In the direction along the optical axis O, the float key 6 that moves forward and backward in the direction along the optical axis O together with the cam frame 5 in the rotation restricted state, and the direction along the optical axis O together with the cam frame 5 in the rotation restricted state. A guide frame 7 that advances and retreats, a group frame 12 that holds a group lens 21 that advances and retreats in the direction along the optical axis O by rotation of the cam frame 5 in a rotation restricted state, and an optical axis O by rotation of the cam frame 5 in a rotation restricted state.
The second group frame 11 holding the second group lens 22 that advances and retreats in the direction along the direction of the cam frame 5 in the rotation restricted state.
The third group frame 10 holding the third group lens 23 and the shutter / third group unit 8 supporting the shutter, and the fixed frame 2 can be advanced and retracted in the direction along the optical axis O. And a fourth group frame 13 that holds a fourth group lens (focusing lens) 24. Here, the first group lens 21, the second group lens 22, the third group lens 23, and the fourth group lens 24 constitute an imaging lens system.

In this lens barrel 1, the cam frame 5 is positioned between the retracted state and the shootable state by rotation when the cam frame 5 moves between the rear moving end and the front moving end, and the optical axis O is in the shootable state. The first lens group 21, the second lens group 22, the third lens group 23, and the fourth lens group 24 are positioned in order from the object side to the image side, and further, the zooming effect is achieved by rotating the cam frame 5 at the front moving end. Is to be executed.

The fixed frame 2 is formed in a cylindrical shape, and a plurality of inclined cam grooves formed in a direction inclined with respect to the optical axis O on the inner periphery thereof, and a circumferential groove formed in a direction along the circumference, Are connected to each other, and a plurality of rectilinear grooves 2b and 2c formed in the optical axis direction. A zoom drive unit 17 for performing a zooming operation of the photographing optical system is provided on the outer peripheral portion of the fixed frame 2, and a focus drive for performing a focusing operation of the photographing optical system is provided inside the fixed frame 2. A unit 18 is provided.

The zoom drive unit 17 includes a zoom motor 17a and a zoom motor 1 that are zoom drive sources.
A gear train (rotation transmission mechanism) 17b for transmitting the driving force of 7a, a position sensor (not shown) for detecting the position of the cam frame 5, a long gear 17c, and the like are included. The zoom motor 1
7a, a zoom optical system that contributes to a zooming operation in the photographing optical system of the lens barrel 1 (
A zooming operation for driving the first group lens 21, the second group lens 22, and the third group lens 23) in the direction along the optical axis O is performed, and a collapsing operation for driving the lens barrel 1 from the photographing enabled state to the retracted state is also performed. . The long gear 17c of the zoom drive unit 17 is disposed in the gear housing portion 2d of the fixed frame 2 so that the rotation axis is parallel to the optical axis O, and rotates while being exposed to the inner peripheral portion of the fixed frame 2. It is supported freely.

The focus drive unit 18 is screwed into a focus motor 18a that is a focus drive source arranged parallel to the optical axis O, a lead screw 18b that is formed integrally with a rotation shaft of the focus motor 18a, and a lead screw 18b. The nut 18c, and a position sensor (not shown) including a photo interrupter for detecting the origin position of the focusing optical system (fourth group lens 24) that contributes to the focusing operation of the photographing optical system of the lens barrel 1 are included. Yes. Then, the focus motor 18a drives the fourth group lens 24 in a direction along the optical axis O. The detailed configuration and operation of the focus drive unit 18 will be described later.

The cam frame 5 is formed in a cylindrical shape, and is fitted in the inner peripheral portion of the fixed frame 2 in a state where the cam frame 5 can rotate and advance and retract. A plurality of cam followers 5 a that are slidably fitted into a plurality of cam grooves 2 a of the fixed frame 2 and a long gear 17 c of the zoom drive unit 17 are provided at the rear peripheral portion of the cam frame 5.
And a gear portion 5b that meshes with each other.

As described above, the cam follower 5a of the cam frame 5 is slidably fitted into the cam groove 2a of the fixed frame 2, and the gear portion 5b is engaged with the long gear 17c. Therefore, when the zoom motor 17a of the zoom drive unit 17 is driven and the long gear 17c is rotationally driven, the driving force is transmitted to the cam frame 5 via the gear portion 5b so that the cam frame 5 is rotated. It has become. When the cam frame 5 rotates in this manner, the cam follower 5a of the cam frame 5 moves along the inclined cam groove portion of the inclined cam groove 2a of the fixed frame 2, so that the cam frame 5 is in a retracted position while rotating. From the (rear moving end), it is advanced forward to the wide end (forward moving end) which is the short focal position in the photographing enabled state. When the lens barrel 1 is in a photographing enabled state, the cam frame 5 has a cam follower 5a and a cam groove during a zooming operation from the wide end that is the short focus position to the tele end that is the long focus position. The circumferential groove 2a is driven only in the rotational direction at the forward moving end without moving forward and backward in the direction along the optical axis O.

Further, a first group cam groove 5c is formed in the outer peripheral portion of the cam frame 5 in a direction inclined with respect to the optical axis O, and two groups are formed in the inner peripheral portion in a direction inclined with respect to the optical axis O. A cam groove 5d and a third group cam groove 5e are formed.

The float key 6 is formed in a cylindrical shape, and is fitted in the inner peripheral portion of the cam frame 5 so as to be relatively rotatable. A guide protrusion 6 a that fits into the rectilinear groove 2 b of the fixed frame 2 projects outwardly from the outer peripheral portion of the rear end of the float key 6. As a result, the float key 6
Is capable of moving back and forth in the direction along the optical axis O together with the cam frame 5 while being restricted in rotation by the fixed frame 2.

The float key 6 is disposed so as to be fitted into the inner peripheral portion of the cam frame 5 in a state where the bayonet protrusion 6b is fitted into the outer peripheral groove 5g of the circular recess provided in the flange portion 5f of the cam frame 5. Yes. As a result, the float key 6 can be rotated relative to the cam frame 5 and is bayonet-coupled so as not to move forward and backward relative to the cam frame 5 in the direction along the optical axis O. .

In addition, the float key 6 has a second group rectilinear groove 6c and a third group rectilinear groove 6d formed so as to penetrate the inner and outer peripheries in the direction along the optical axis O.

Further, the guide projection 11a of the second group frame 11 is fitted in the second group straight advance groove 6c of the float key 6, and the guide projection 10b of the third group unit 10 is fitted in the third group straight advance groove 6d. Thereby, the float key 6 supports the second group frame 11 and the shutter / third group unit 8 so as to be able to advance and retreat, and restricts the rotation.

The guide frame 7 is formed in a cylindrical shape, and a coupling groove (not shown) of the cam frame 5 in the inner periphery of the rear end.
It has a bayonet protrusion (not shown) that fits in. In addition, the inner periphery of the guide frame 7
In a direction along the optical axis O, a rectilinear groove 7b into which a cam follower 12a formed on the rear outer peripheral portion of the first group frame 12 is fitted is formed.

The guide frame 7 is disposed in a bayonet connection with the cam frame 5 in a state where the guide frame 7 is fitted into the inner peripheral portion of the fixed frame 2. At this time, the guide protrusion 7 a of the guide frame 7 is moved into the straight groove 2 of the fixed frame 2.
c. As a result, the guide frame 7 moves integrally with the cam frame 5 in the direction along the optical axis O in a state where the rotation is restricted with respect to the fixed frame 2, as with the float key 6. ing.

The second group frame 11 is formed in a cylindrical shape and is arranged in a state of being fitted into the inner peripheral portion of the float key 6. A second group lens 22 is held at a substantially central portion of the second group frame 11, a guide projection 11a projecting outward on the outer peripheral portion, and projecting outward on the guide projection 11a. Cam follower 11b.

The guide protrusion 11 a is fitted into the second group straight advance groove 6 c of the float key 6, and the cam follower 1
Reference numeral 1b denotes a second group cam groove 5 of a cam frame 5 which is inserted through the second group straight movement groove 6c and provided on the outer side thereof.
It is slidably fitted into d. As a result, the second group frame 11 is driven to advance and retract by the rotation of the cam frame 5 while being restricted in rotation by the float key 6.

The second group frame 11 is configured such that when the cam frame 5 is positioned at the rearward movement end, a part of the image side is fitted into the inner peripheral side of the shutter frame 30 together with a part of the lens on the image side. Yes.

The first group frame 12 is formed in a cylindrical shape, and is arranged in a state of being fitted between the cam frame 5 and the guide frame 7. A first group lens 21 is held on the object side of the first group frame 12.
In addition, a plurality (for example, three inward) of the inner peripheral portion of the first group frame 12 is formed at equal intervals in the inner peripheral direction so as to fit into the first group cam grooves 5c formed on the outer peripheral portion of the cam frame 5. Cam followers (not shown).

As described above, the cam follower 12a formed on the outer peripheral portion of the rear end of the first group frame 12 is
The cam follower formed on the inner peripheral portion of the group frame 12 is fitted in the group groove cam groove 5 c formed on the outer peripheral portion of the cam frame 5. Match. As a result, the group frame 12 is driven to advance and retract by the rotation of the cam frame 5 while being restricted in rotation by the guide frame 7.

The shutter / third group unit 8 includes a shutter frame 30 that holds the shutter mechanism and a third group frame 10 that holds the third group lens 23 on the rear side of the shutter frame 30.

The shutter frame 30 is configured in such a manner that a substantially circular plate member having an opening at a substantially central portion holds a shutter mechanism including a shutter blade that opens and closes the central opening and a shutter actuator that rotationally drives the shutter blade. It is configured.

The third group frame 10 includes a cylindrical holding portion 10 a that holds the third group lens 23, and the holding portion 10 a is fitted into the shutter frame 30 from the rear of the shutter frame 30, and the shutter frame 3.
It is fixed at 0. Further, the third group frame 10 is provided with a plurality of (for example, three) guide protrusions 10b outwardly at equal intervals in the outer peripheral direction on the front outer periphery, and the guide protrusions 10b further include Cam followers 10c are provided so as to project outward.

Further, the third group frame 10 is arranged in a state of being fitted inside the float key 6, and the guide protrusion 10 b is fitted into the third group straight groove 6 d of the float key 6, and penetrates through this to follow the cam follower 10.
c is inserted into the cam groove 5 e for the third group of the cam frame 5. Accordingly, the third group rectilinear frame 30 is driven to advance and retract by the cam frame 5 in a state in which the rotation is restricted by the float key 6.

A coil spring 35 is disposed between the second group frame 11 and the shutter / third group unit 8. As a result, the second group frame 11 and the shutter / third group unit 8 are biased in a direction away from each other. One end of the coil spring 35 has a shutter frame 30 of the shutter / third group unit 8.
The other end is inserted so as to be fitted to the outer peripheral portion of the lens holder portion of the second group frame 11.

A neutral density filter (ND filter) 40 is attached to the image side of the third group lens. By disposing on the image side of the third lens group, a smaller ND filter can be used as compared with the case where it is disposed between other parts, for example, between the second lens group 22 and the third lens group 23.
The ND filter 40 may not be provided.

The fourth group frame 13 is a substantially disk-shaped frame member having a circular opening at the center for holding the fourth group lens 24. The fourth group frame 13 is supported by the focus drive unit 18 so as to be movable back and forth in the optical axis direction inside the fixed frame 2. The focus drive unit 18 is coupled to the fixed frame 2 via an LD main body 19 and a base member 101 which are members for fixing the focus drive unit.

Next, a mechanism for supporting and driving the fourth group frame 13 by the focus driving unit 18 will be described. 5 is a cross-sectional view including the fourth group lens 24, the fourth group frame 13, and the focus drive unit 18 of the imaging unit shown in FIG. This figure is a cross-sectional view of a cross section that simultaneously passes through the central axes of a lead screw 18c and a focus guide shaft 18f described later.

The focus motor 18a has a support frame 18d formed integrally with the housing of the focus motor 18a. The support frame 18d extends from the side of the housing of the focus motor 18a in the optical axis direction, and has a shape in which the tip is bent toward the rotation axis of the motor. The leading end of the support frame 18d is a lead screw 18 formed integrally with the rotation shaft of the focus motor 18a.
The tip of b is rotatably supported. Therefore, the lead screw 18b is supported at both ends by the focus motor 18a and the tip of the support frame 18d. By doing in this way, generation | occurrence | production of the vibration accompanying rotation of the lead screw 18b can be prevented, and the focus drive unit 18 can be silenced. The support frame 18d is provided with a screw hole, and is fixed to the LD main body 19 by a focus motor mounting screw 18e.

Further, a nut 18c is screwed to the lead screw 18b in a state where the rotation is restricted by the support frame 18d. Therefore, when the focus motor 18a is driven, the lead screw 18b rotates, and the nut 18c moves forward and backward along the lead screw in accordance with this rotation.

In addition, a main focus guide shaft 18f extending in the optical axis direction is inserted into the LD main body 19 at a position close to the focus motor 18a, and a sub-extension extending in the optical axis direction at a position away from the focus motor. A focus guide shaft 18h (see FIG. 1) is inserted. Since the main focus guide shaft 18f and the sub focus guide shaft 18h penetrate the fourth group frame 13 slidably, the fourth group frame 13 extends along the main focus guide shaft 18f and the sub focus guide shaft 18h in the optical axis direction. Can be moved to. Further, since the sub focus guide shaft 18h is provided in addition to the main focus guide shaft 18f, the fourth group frame 13 has the main focus guide shaft 18h.
Rotation around f is prevented.

Further, the lead screw 18b passes through the outer periphery of the fourth group frame 13 between the focus motor 18a and the nut 18c. On the other hand, an urging spring is wound around the main focus guide shaft 18f between the LD main body 19 and the fourth group frame 13, and the LD main body 19 and the fourth group frame 13 are urged away from each other. . As a result, the fourth group frame 13 is always in contact with the rear surface of the nut 18c.

The LD main body 19 is connected to an FPC board 117 including a drive signal line to the focus driving focus motor 18a and an origin position detection signal line to the control circuit of the imaging apparatus (see FIGS. 2 to 4). .

Thereby, when the lead screw 18b is rotated by the driving force of the focus motor 18a of the focus drive unit 18, the nut 18c is driven forward and backward along the lead screw 18b. When the nut 18c is driven back and forth, the fourth group frame 13 in contact with the rear surface of the nut 18c is driven back and forth in the direction along the focus guide shafts 18f and 18h, that is, the direction along the optical axis O, and photography is possible. It is adjusted to an appropriate focusing position when it is in the state, and is positioned at a predetermined retracted position during the retracting operation.

In FIG. 5, the rear end portions of the focus motor 18a and the main focus guide shaft 18f and a part of the LD main body 19 fitted therewith are the lens surfaces on the rear side (image side) of the fourth group lens 24 at the retracted position. Protrudes backwards. As will be described later, these portions are disposed so as to penetrate the camera shake correction device. On the other hand, the sub focus guide shaft 18h does not penetrate the camera shake correction device 105.

Next, the configuration of the sensor unit 100 will be described with reference to FIG.

The sensor unit 100 is a unit that includes an image blur correction device 105 that performs image blur correction and an image sensor 110 that generates image data. The image blur correction device 105 includes the base member 1.
01 and a Y guide shaft 10 that is supported by the base member 101 extending in the Y direction (first direction).
9, 111, a Y feed screw 112 and an X feed screw 113 extending and supported in the X direction (second direction), and supported by a Y guide shaft 111 and a Y feed screw 112 so as to be movable in the Y direction. Slider 114 and X guide shaft 11 supported by slider 114 extending in the X direction
5, 116, a sensor holding frame 119 slidably supported in the X direction by the X feed screw 113 and the X guide shafts 115, 116, and an optical low-pass filter 118 attached to the sensor holding frame 119 (see FIGS. 2 to 4). ) And the image sensor 110 (see FIGS. 1 to 4), and a Y motor (first motor) 120 and an X motor (second motor) 13 supported by the base member 101.
0 (see FIG. 1).

Note that the X direction and the Y direction are directions orthogonal to each other and orthogonal to the optical axis O, and are directions along the horizontal direction (X direction) and the vertical direction (Y direction) of the image sensor 110.

The Y motor 120 rotates the Y feed screw 112 via the gear train 121 to move the slider 114.
This is a stepping motor that drives in the Y direction. Further, the X motor 130 has a gear train 13
The stepping motor rotates the X feed screw 113 through 1 to drive the sensor holding frame 119 in the X direction. An FPC (not shown) connected to the base circuit board is connected to the Y motor 120 and the X motor 130 and driven. Thus, the sensor holding frame 119
Is driven along a plane parallel to the light receiving surface of the image sensor 110 by the Y motor 120 and the X motor 130 so as to correct the image shift of the optical image formed on the image sensor 110 via the lens barrel 1. It has become.

The Y guide shaft 111 and the X guide shaft 116 are respectively provided with compression coil springs 122.
132 are wound. Further, tension coil springs 123 and 133 are suspended between the base member 101, the slider 114, and the sensor holding frame 119, respectively. As a result, the slider 114 and the sensor holding frame 119 are each biased to the origin position.

The image sensor 110 is connected to the FPC 141 and mounted on the sensor holding frame 119. A heat radiating plate 142 is attached to the sensor holding frame 119 on the back side of the image sensor 110 so as to sandwich the FPC 141.

Here, the base member 101 of the image blur correction device 105 is a combination of a semi-circular shape and a rectangular shape so that a straight portion of the semi-circular shape matches one side of the rectangular shape as viewed from the lens barrel 1 side. It has a shape. Of the two corners of the rectangular portion, the first corner 151 has a Y motor 120.
1st drive part 161 containing gear train 121 and the 2nd corner 15 which is the other corner is carried.
2, a second drive unit 162 including an X motor 130 and a gear train 131 is mounted.

Further, the arc of the semicircular portion of the base member 101 extends along the outer periphery of the rear end portion of the fixed frame 2, and the outside of the opposite base member 101 via the second corner 152 and the optical axis O, that is, the fixed frame 2. A zoom drive unit 17 is disposed outside the lens. The zoom motor 17a of the zoom drive unit 17 is connected to a long gear 17c in the gear housing portion 2d of the fixed frame 2 via a gear train 17b (see FIG. 1).

A focus drive unit 18 is provided inside the fixed frame 2 at a position where it does not interfere with the optical system. The focus motor 18a has a rear end fixed to the LD main body 19 with the motor shaft facing forward. It protrudes and penetrates into the blur correction unit 105. Further, the rear end portion of the main focus guide shaft 18 f also penetrates the image blur correction device 105 while being fixed to the LD main body 19. The focus motor 18a and the main focus guide shaft 18f are provided with a notch portion between the heat sink 142 and the slider 114 so that the sensor unit 100 has an opening when viewed in the optical axis direction. The part is penetrated in the direction along the optical axis. That is, the focus motor 18a and the main focus guide shaft 18f are connected to the slider 1
14 and the sensor holding frame 119. Further, the focus motor 18a
The main focus guide shaft 18f and the heat radiating plate 142 and the slider 114 have a gap so that they do not come into contact with each other when the heat radiating plate 142 and the slider 114 move in the X direction and / or the Y direction during image blur correction. ing. With such a structure, the outer diameter of the fixed frame can be reduced. Therefore, the strobe and the tripod screw can be brought closer to the fixed frame, and the imaging apparatus can be downsized. Further, when the lens barrel 1 and the sensor unit 100 are assembled, the focus driving unit 18 and the image blur correction device 105 do not interfere with each other, and the focus motor 18a and the main focus guide are provided from the rear of the image blur correction device 105. Since the position of the shaft 18f can be visually confirmed, assembly is easy.

The FPC 141 to which the image sensor 110 is connected extends from the image sensor 110 in the X direction on the back side of the base member 101. The FPC 141 is connected to a base circuit board so that an image captured by the image sensor 110 is displayed on a display device such as a liquid crystal panel (not shown) and recorded on a recording medium.

Hereinafter, the operation of the imaging apparatus according to the present embodiment configured as described above will be described.

First, in order to make the imaging device ready for photographing by starting the imaging device or the like, the cam frame 5 is rotated clockwise by the zoom drive unit 17, and the lens barrel 1 is retracted (backward movement end).
To the forward moving end. When the cam frame 5 is positioned at the front moving end and becomes the wide end which is the short focal position, as shown in FIG. 3, each frame member moves in the direction along the optical axis O toward the front. Thus, the lens barrel 1 is in an extended state as a whole.

Next, at the time of zoom adjustment, the positions of the first group frame, the second group frame, and the third group frame are adjusted so that the cam frame 5 is rotated at the forward movement end and a desired image magnification is obtained. For example, at the telephoto end that is the long focal position, as shown in FIG. 4, the lens barrel 1 is fully extended, and the positions of the second group frame and the third group frame are adjusted accordingly. .

Further, at the time of focus adjustment, the focus drive unit 18 is driven to drive the fourth group frame 13 forward and backward in the optical axis direction, and the position of the fourth group lens 24 in the optical axis direction is adjusted. As a result, it is possible to capture an image whose focus is adjusted at a desired image magnification.

At the time of imaging, the direction of camera shake is detected by a sensor such as an angular velocity sensor (not shown),
By driving the first drive unit 161 and the second drive unit 162 of the image blur correction device 105, the sensor holding frame 119 is driven in a direction opposite to the direction of camera shake, thereby correcting the image blur. At that time, the focus motor 18a and the main focus guide shaft 18f are used by the image blur correction device 105.
However, since a gap is provided between the focus motor 18a and the focus guide shaft 18f and the image blur correction device when viewed from the optical axis direction, image blur correction is not hindered.

Further, since the focus motor 18a and the main focus guide shaft 18f pass through the gap between the slider 114 of the image blur correction device 105 and the sensor holding frame 119, the focus motor 18a and the main focus guide shaft 18f are It is not necessary to arrange the image blur correction device 105 while avoiding the position on the back side of the position where the image blur correction device 105 is arranged. For this reason, it is possible to reduce the diameter of the fixed frame 2. As a result, a strobe, a tripod screw, etc., can be attached
It is possible to reduce the size of the entire apparatus.

Further, when the photographing enabled state is ended, for example, when the power of the imaging device is turned off, the cam frame 5 of the lens barrel 1 is rotated counterclockwise, and each frame member is moved along with the rotation of the cam frame 5. It moves to the rear along the optical axis O to be in the retracted state shown in FIG. At that time, the focus motor 18a and the main focus guide shaft 18f are housed by effectively using a dead space formed in the lens barrel behind the first group lens 21 having the largest diameter.

As described above, according to the present embodiment, the lens barrel 1 includes the fourth group lens 24 that is a focusing lens and the focus drive unit 18 that drives the fourth group lens 24 to advance and retract along the optical axis. Since the focus motor 18a and the main focus guide shaft 18f, which are part of the focus drive unit 18, penetrate through the image blur correction device 105 so as not to interfere with the image blur correction device 105, they are fixed. The diameter of the frame 2 can be reduced, and the apparatus body can be reduced in size.

Note that the image blur correction device 105 is not limited to the focus motor 18a and the main focus guide shaft 18f, but the sub guide shaft 18h and other focus drive units 18.
It can also be made into the component of. Or, only one of the focus motor 18a or the main focus guide shaft 18f enters the image blur correction device 105 [for example, image blur so that the rear end of the electromagnetic linear motor or the guide shaft support portion on the optical axis does not interfere. It may be positioned rearward (image side) from the forefront of the correction device, or a notch recess may be formed in a part of the movable portion in the image blur correction device.
In particular, when the focus motor 18a, which is a relatively large member, enters the image blur correction device 105, by providing a through hole in a part of the image blur correction device, the lens and the lens frame can be arranged in the retracted state. It becomes easy and the imaging device 1 can be downsized.

Further, when the focus motor 18a and the main focus guide shaft 18f are viewed in the optical axis direction,
Since it passes through the outside of the moving area of the sensor holding frame 119 within the area of the slider 114 of the image blur correction apparatus 105, the focus driving unit 1 is positioned closer to the image sensor 110.
8 can be arranged. Therefore, the lens barrel 1 and the entire imaging apparatus can be further downsized.

(Modification)
7a to 7d are a rear view and a sectional view of a moving coil linear motor according to a modification of the focus drive unit according to the present embodiment.
A focus drive unit using a moving coil linear motor (also referred to as an electromagnetic linear motor) instead of the focus motor 18a as shown in FIGS. 7a to 7d will be described.

  Next, the drive mechanism of the fourth group lens 24 using the electromagnetic linear motor using the air-core coil as the drive source (the electromagnetic linear motor 18 that is the drive source of the focus drive unit) will be described.

  FIG. 7 a is a rear view of the fourth group lens 24, the fourth group frame 13, and the electromagnetic drive unit 18. FIGS. 7 b to 7 d are cross-sectional views of the fourth group lens 24, the fourth group frame 13, and the electromagnetic linear motor 18. The configuration of the electromagnetic linear motor 18 will be described.

  The three outer yokes 18 ca to 18 cc have a rectangular shape extending in the optical axis direction, and the outer yoke 18 ca is fixed to the vertical portion 19 a of the LD main body 19 with mounting screws 18 e. The three outer yokes are joined together by auxiliary members 18cg (magnetic material) having four corners to form concave portions. The inner yoke 18b has a rectangular shape extending in the optical axis direction, and both ends thereof are fixed to the side walls 18ce and 18cf of the auxiliary member 18cg. The three permanent magnets 18aa to 18ac are magnetized in the thickness direction and have a rectangular shape extending in the optical axis direction, and are fixed to the flat surfaces of the three outer yokes 18ca to 18cc.

Further, the side wall 18cf of the auxiliary member 18cg and the permanent magnets 18aa to 18ac have a gap on the image side when viewed in the optical axis direction, and the subject side is connected to the end surface of the permanent magnets 18aa to 18ac and the side wall 18ce of the auxiliary member 18cg. Make contact. The permanent magnets 18aa to 18ac and the inner yoke 18b form a magnetic gap. The protrusion 13a of the fourth group frame 13 is incorporated in the opening 18ch of the auxiliary member 18cg, and the drive coil 18d has an “A” -shaped air core in a plane perpendicular to the optical axis direction when viewed from the subject side. It is bonded and fixed to the protrusion 13 a of the group frame 13. And it arrange | positions in the said magnetic clearance gap. Further, the sub-focus guide shaft 18h is fixed to the LD main body 19, and when assembled, it is arranged parallel to the axial direction. The sub focus guide shaft 18h is inserted into the sliding portion 13c of the fourth group frame 13, and the fourth group frame 13 is supported by two guide shafts parallel to the optical axis direction of the main focus guide shaft 18f and the sub focus guide shaft 18h. Is done. This support serves as a rotation stopper when the fourth group frame 13 moves in the optical axis direction (prevents the generation of the rotational moment of the fourth group frame 13).

  As described above, as shown in FIGS. 7B to 7D, the tip of the auxiliary member 18cg is configured to penetrate the image blur correction device. As a result, it is possible to provide a small imaging device without interference between a part of the electromagnetic linear motor 18 and the image blur correction device.

  Further, by arranging the three permanent magnets 18aa to ac so as to face the three surfaces of the drive coil 18d of the fourth group frame 13, drive sensitivity when driving the fourth group lens 24 of the fourth group frame 13 in the optical axis direction. Can be improved.

The outer yokes 18ca to 18cc are made of an auxiliary member 18cg made of a magnetic material and a side wall 18ce. Of the auxiliary member 18cg. It is good also as sheet-metal processing integrated by 18cf.
Next, the operation of the electromagnetic linear motor 18 that is a drive source of the focus drive unit will be described.

An applied voltage is applied to the drive coil 18d from a focus drive circuit (not shown). A magnetic circuit is formed by the magnetic gap between the permanent magnets 18aa, 18ab, 18ac of the electromagnetic linear motor 18 and the outer yokes 18ca, 18cb, 18cc and the inner yoke 18b. The fourth group frame 13 holding the fourth group lens 24 moves in the optical axis direction by the voltage applied to the drive coil 18d and the thrust of this magnetic circuit (also called a drive action line where the magnetic flux and the coil current intersect).

At this time, the fourth group frame 13 is guided by the main focus guide shaft 18f and the sub focus guide shaft 18h. The LD main body 19 is provided with a main focus guide shaft 18 f extending in the optical axis direction at a position close to the focus drive unit 18 using an electromagnetic linear motor, and is separated from the electromagnetic linear motor 18. The sub-focus guide shaft 18h (see FIG. 1) extending in the optical axis direction is also inserted at the position. Since the main focus guide shaft 18f and the sub focus guide shaft 18h penetrate the fourth group frame 13 slidably, the fourth group frame 13 extends along the main focus guide shaft 18f and the sub focus guide shaft 18h in the optical axis direction. Can be moved to.

Further, since the sub focus guide shaft 18h is provided in addition to the main focus guide shaft 18f, the fourth group frame 13 is prevented from rotating around the main focus guide shaft 18f.
In FIG. 7b as well, the electromagnetic drive unit 18, the rear end of the main focus guide shaft 18f, and a part of the LD main body 19 fitted thereto are the rear side (image side) of the fourth group lens 24 at the retracted position. It protrudes behind the lens surface. As will be described later, these portions are disposed so as to penetrate the camera shake correction device. On the other hand, the sub focus guide shaft 18h does not penetrate the camera shake correction device 105. Here, the electromagnetic linear motor has been described with respect to the movable coil type, but it may be replaced with a movable magnet type linear motor in which three movable magnets are fixed to the movable part.

The LD main body 19 is connected to an FPC board 117 including a drive signal line to the movable coil 18d of the electromagnetic linear motor 18 as a focus drive source and an origin position detection signal line to the control circuit of the imaging apparatus.

  According to a fourth aspect of the present invention, in the imaging device according to the first or second aspect, the cross-sectional area of the main focus guide shaft is larger than the cross-sectional area of the sub-focus guide shaft.

  According to a fifth aspect of the present invention, when the electromagnetic linear motor is viewed from the object side, the distance between the drive action line where the magnetic flux of the drive coil and the magnetic circuit intersect with the main focus guide axis is the distance between the drive action line and the sub focus guide axis. It is characterized by being shorter than the distance.

The main focus guide shaft needs to guide the fourth group lens without deviating from the optical axis, and has sufficient rigidity. If the shaft bends due to insufficient rigidity, tilt and eccentricity occur in the fourth group lens, leading to deterioration of optical performance.
When vibration occurs on the shaft, the AF performance deteriorates. In addition, a moving image or the like gives an unpleasant feeling to the user.
Even if the sub focus guide shaft bends, the fourth group lens does not tilt. Further, by arranging the main focus guide shaft at a distance, the occurrence of eccentricity due to the deflection of the shaft can be reduced. Therefore, it can be made thinner than the main focus guide shaft, and the lens barrel and the entire imaging apparatus can be reduced in size.
The electromagnetic linear motor is placed near the main focus guide. If driving is attempted at a position away from the main focus axis, chattering may occur or twisting may occur and driving may not be possible.

In this case, it can be driven by arranging a plurality of electromagnetic linear motors, but this increases the cost and complicates the control. This leads to an increase in the size of the lens barrel and the entire imaging apparatus.
As shown in FIG. 7 a, an MR sensor attachment portion 18 i is provided on one side surface of the fourth group frame 13. (MR sensor and magnetic scale are not shown) This MR sensor mounting portion 18i is provided with a Hall element (or a Kerr effect detection photo reflector) integrally joined to the fourth group frame 13. The detection surface of the MR sensor is positioned close to and opposed to the outer surface of the auxiliary member. The fourth group frame 13 and the MR sensor move together in the optical axis direction. Near the MR sensor, it is arranged on the outer surface of the auxiliary member 18g to which a magnetic scale having a large number of NS pole pieces joined in a row (formed at a predetermined pitch) is fixed at a position facing the MR sensor. A desired amplitude signal is output by moving the MR sensor (Hall element). The control circuit (CPU) counts changes in the MR sensor signal and generates an interpolation signal in the vicinity of the zero cross near the target position, thereby energizing the drive coil 18d disposed integrally with the fourth group frame 13 to thereby provide an optical axis. A high-speed movement operation is performed in the direction, and the movement of the fourth group lens 24 of the fourth group frame 13 to the target position is stopped with high speed and high accuracy. In this case, by using this MR sensor and the magnetic scale, the fourth group lens 24 held by the fourth group frame 13 within a range that moves between the close end and the infinity end by focus drive during photographing is desired. Position to the position. Further, at the time of sinking, the fourth group lens 24 of the fourth group frame 13 moves to the most image sensor side and stops. Further, positioning is performed from the sinking position to a standby position (also referred to as an initial position) that stops first when the camera is activated. The fourth group lens 24 (shown by a two-dot chain line in FIGS. 7a to 7d) of the fourth group frame 13 is the maximum extension position of the fourth group lens 24 held in the fourth group frame 13 at the position closest to the subject in the photographing range. .
As a modification, when a magnetic scale (not shown) is directly attached to the outer yoke 18cb of magnetic material (attached with an adhesive or double-sided tape), the Hall element is erroneously detected due to the influence of leakage magnetic flux of the outer yoke. A flat plate made of a non-magnetic material (for example, SUS material) may be interposed between the magnetic scale and the outer yoke 18cb.

Other modifications are as follows.
For example, the fourth group lens 16 or the third group lens 54 shown in FIGS. 5 and 10 of Japanese Patent Laid-Open No. 2005-234075 can be used for a minute distance reciprocation (warbing) along the optical axis direction.
Moreover, although the modified example of this invention demonstrated the moving coil type | mold electromagnetic linear motor, of course, it is good also as a moving magnet type | mold linear motor (it is also called an electromagnetic linear motor).

DESCRIPTION OF SYMBOLS 1 Lens barrel 13 Fourth group frame 13a Protrusion part 13b Sliding part 18 Electromagnetic linear motor (drive source of focus drive unit)
18aa, 18ab, 18ac Permanent magnet 18b Inner yoke 18ca, 18cb, 18cc Outer yoke 18cg Auxiliary member 18ch Auxiliary member opening 18d Drive coil 18f Main focus guide shaft 18h Sub focus guide shaft 19 LD main body 105 Image blur correction device 119 Sensor holding frame

Claims (5)

A lens barrel holding an imaging lens system comprising a plurality of lenses including a focusing lens;
An imaging element that receives an optical image formed through the imaging lens system and generates image data;
An image blur correction device that performs an image blur correction operation by displacing the image sensor in a plane parallel to the light receiving surface of the image sensor;
The lens barrel includes an electromagnetic linear motor that drives the focusing lens to move back and forth along the optical axis, and the image blur correction device prevents a part of the electromagnetic linear motor from interfering with the image blur correction device. An imaging device characterized in that it is embedded. 2. A part of the electromagnetic linear motor enters the image blur correction device, wherein a through hole or a notch is formed in a part of the image blur correction device. Imaging device. The image blur correction device includes a base member to which the lens barrel is fixed, a slider supported by the base member so as to be movable in a first direction orthogonal to the optical axis, and the optical axis and the slider by the slider. A sensor holding frame that holds the imaging element supported so as to be movable in a second direction orthogonal to the first direction, and a part of the electromagnetic linear motor is seen in the optical axis direction. 3. The imaging apparatus according to claim 1, wherein the imaging apparatus passes through an outside of a movement area of the sensor holding frame in the area of the slider. 4. 3. The imaging apparatus according to claim 1, wherein a cross-sectional area of the main focus guide shaft is larger than a cross-sectional area of the sub-focus guide shaft.   The distance between the drive action line and the main focus guide axis where the magnetic flux of the drive coil and the magnetic circuit intersect is shorter than the distance between the drive action line and the sub focus guide axis when viewed from the subject side in the electromagnetic linear motor. The imaging device according to claim 4.

Images