JP2000227614A - Lens barrel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce leakage flux while realizing the reduction of cost and the minaturization of a lens barrel because the performance of an actuator is deteriorated by the influence of disturbance magnetic field in the case of using a magnetic sensor as the position detecting sensor of an actuator for zooming and focusing in the lens barrel having an image blur correcting device. SOLUTION: In this lens barrel, the magnetic sensor 41 of a linear actuator 33 is arranged at a position where it can cancel the influence of the disturbance magnetic field with respect to the actuators 6p and 6y for pitching and yawing moving frames holding an image blur correction lens group. Furthermore, the magnetic sensor 51 of a stepping motor 47 with an encoder is arranged at the position where it can cancel the influence of the disturbance magnetic field.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lens barrel used for a video camera or the like.

[0002]

2. Description of the Related Art In general, a lens barrel for a video camera is composed of four lens groups, and a moving lens group for zooming and focusing is guided by a guide pole and moved in the optical axis direction. I have.

FIG. 9 in JP-A-8-240759 shows a lens barrel in the above-mentioned conventional example.

In the conventional lens barrel described above, a fixed lens group 101, a lens group 102 moving on an optical axis for zooming, a fixed lens group 103, zooming and focus adjustment are shown in FIG. Lens group 1 moving on the optical axis for
04, an aperture unit 105, and an imaging surface 106.

The lens moving frames 107 and 108 are moving frames for holding the moving lens groups 102 and 104, respectively.
Actuators 109 and 110 for driving the lens moving frames 107 and 108 in the direction of the optical axis, respectively, are constituted by stepping motors. Stepping motor 10
9 and 110 are provided with screw portions 109a and 110a of the output shaft, and are connected to the lens moving frames 107 and 108 by connecting members 111 and 112. The guide poles 113 and 114 move the lens moving frames 107 and 108,
It is held movably in the optical axis direction.

In such a lens barrel, when the stepping motor 109 is energized through an electric signal line (not shown), the output shaft rotates, and the connecting member 111 screwed with the screw portion 109a becomes an optical axis. Move in the direction. Then, the lens moving frame 107 engaged with the connecting member 111, that is, the moving lens group 102 moves in the optical axis direction. Similarly, when power is supplied to the stepping motor 110 via an electric signal line (not shown), the output shaft rotates, and the connecting member 112 screwed with the screw portion 110a moves in the optical axis direction. Then, the lens moving frame 108 engaged with the connecting member 112, that is, the moving lens group 104 moves in the optical axis direction.

[0007]

However, the above-mentioned conventional lens barrel has the following problems.

(1) A stepping motor used as a conventional lens barrel actuator can be stopped at a predetermined position by rotating the stepping motor by an angle corresponding to a predetermined number of pulses. However, since the drive control of the stepping motor is an open loop, there are problems such as poor stop position accuracy, hysteresis characteristics, and a relatively low rotational speed. Therefore, when a stepping motor is used as a drive source of a feed mechanism of a lens moving frame for zoom and focus,
Slow zoom and focus speed.

In order to solve this problem, as disclosed in Japanese Patent Application Laid-Open No. Hei 8-266093, a control system is improved to a closed loop control by attaching a sensor for detecting the rotation angle of a stepping motor. There has been proposed a stepping motor system with an encoder that enables high-speed rotation drive.

In addition, a linear actuator system which is excellent in high-speed response and low power consumption which can follow a change in the position of a focus lens group by using a voice type linear actuator instead of the conventional stepping motor can be considered. Therefore, in order to achieve high-speed response and low power consumption for both zoom and focus, a stepping motor with an encoder is used to drive the zoom lens group, and a linear actuator is used to move the focus lens group. It is optimal to use a system to be used, and as a position detection sensor of the system, it is common to use a magnetoresistive sensor (hereinafter abbreviated as a magnetic sensor) in order to improve position detection accuracy.

However, as the size and weight of the video camera have been reduced in recent years, the size and weight of the lens barrel are also desired to be reduced. Therefore, the interval between components constituting the lens barrel tends to be reduced. Here, in general, when a magnetic sensor is affected by a disturbance magnetic field, its sensor output is distorted, and there is a problem that the performance of the actuator is deteriorated, and the leakage from the above-described stepping motor with encoder and the driving magnet of the linear actuator is problematic. The magnetic flux is not negligible because the space between components becomes smaller with the downsizing of the lens barrel, and in particular, there is a problem that the magnetic flux from the driving magnet of the linear actuator adversely affects the magnetic sensor of the stepping motor with the encoder.

As a countermeasure against the leakage magnetic flux, there is conventionally a method of separately using a magnetic shield part or the like. However, the use of the magnetic shield part leads to an increase in cost, and in order to further reduce the size of the lens barrel, it is necessary to use such a method. No space. Therefore, in a lens barrel that is reduced in size and weight, a system that mounts both a stepping motor with an encoder and a linear actuator and that achieves high-speed response and low power consumption for driving a zoom and focus lens cannot be realized. (2) With the reduction in size and weight of the lens barrel and the increase in magnification, there is a problem that it is difficult to obtain a stable screen due to camera shake, especially on the long focal length side. For this reason, conventionally, an electronic method has been used as a camera shake correction method. However, the lens barrel is smaller and lighter,
If the amount of camera shake increases with the increase in magnification, the correction range needs to be expanded, but the electronic camera shake correction range is CC
Since it depends on the number of pixels of D, it is necessary to increase the number of pixels. Further, with the miniaturization of the CCD and the improvement of the image quality of the video camera, the limit of the increase in the number of pixels of the CCD occurs, and the electronic image stabilization system fails.

Therefore, an optical image stabilization system which has a large correction range and can achieve high image quality has been proposed. Among such optical image stabilization systems, as disclosed in Japanese Patent Application Laid-Open No. HEI 3-186823, a predetermined lens group is moved in a plane perpendicular to the optical axis to correct image stabilization. A scheme has been proposed.

In the inner shift system, a lens group necessary for image formation can be shared with a shift lens group for blur correction means, so that the lens barrel can be shortened and the size and weight can be reduced. However, in order to move the correction lens group in a direction perpendicular to the optical axis, it is necessary to separately add two actuators. That is, in addition to the actuators for driving the zoom, focus, and aperture which have been configured by the conventional lens barrel, two shift actuators for camera shake correction are required, so that a total of five actuators are combined into one lens barrel. It is necessary to arrange inside.

Therefore, it is difficult to reduce the size of the lens barrel due to an increase in the number of actuators, which is inconsistent with the recent reduction in the size of the lens barrel. Becomes (3) Further, as shown in the above-mentioned problem (1), when a stepping motor with an encoder using a magnetic sensor and a linear actuator are mounted as zoom and focus actuators, two shift actuators for image blur correction are used. This causes a problem that leakage magnetic flux is generated and adversely affects the magnetic sensor.

Accordingly, the present invention has been made to solve the above-mentioned conventional problems, and an object of the present invention is to provide a lens barrel equipped with a linear actuator and a stepping motor with an encoder, which is reduced in size and weight. It is. Further, it is intended to realize a small and lightweight lens barrel equipped with a shift actuator for camera shake correction.

[0017]

In order to solve the above-mentioned problems, a lens barrel according to the present invention comprises a magnet magnetized perpendicular to a driving direction, a yoke, and a magnet having a predetermined gap between the magnet and the magnet. A coil that is movable in the driving direction by applying a current perpendicular to the magnetic flux to be applied, a linear actuator constituted by a position detecting means, a stepping motor, and a cylindrical or columnar, circumferentially A stepping motor with an encoder, which is composed of an encoder magnet rotatably mounted coaxially with the stepping motor and a magnetic sensor disposed opposite to the periphery of the encoder magnet, and a linear actuator. A first moving lens group driven in the optical axis direction and a stepping motor with an encoder; A second moving lens group driven in the optical axis direction, and a magnetic sensor of a stepping motor with an encoder disposed at a substantially symmetric center position when viewed from a driving direction of a magnetic circuit composed of a magnet and a yoke of a linear actuator. It is characterized by having done.

Further, the lens barrel of the present invention holds the image blur correction lens group, and is slidable in first and second directions orthogonal to the optical axis at different heights in the optical axis direction. , A second lens moving frame, and first and second actuators for driving the first and second lens moving frames, and are disposed on the optical axis image plane side of the first and second actuators. The actuator is characterized in that it is disposed so as to overlap a lens moving frame disposed on the optical axis object side when viewed from the optical axis direction.

Further, the lens barrel of the present invention holds the first lens group for image blur correction, and slides in the first and second directions orthogonal to the optical axis at different heights in the optical axis direction. Movable first and second lens moving frames, first and second actuators for driving the first and second lens moving frames, and linear actuators for moving the second lens group in the optical axis direction Wherein the first and second actuators are disposed in the optical axis direction on the optical axis image plane side of the actuator disposed on the optical axis object side.

Further, the lens barrel of the present invention holds a first lens group for image blur correction, and is slidable in first and second directions orthogonal to the optical axis. A lens moving frame, first and second actuators for driving the first and second lens moving frames, a fixed frame for slidably holding the first and second lens moving frames, and a second lens A stepper motor with an encoder for moving the group in the optical axis direction, wherein the fixed frame has a recess formed in a portion surrounded by the first and second actuators, and the stepper motor with the encoder is disposed in the recess. It is characterized by the following.

Further, the lens barrel of the present invention holds first and second lens moving frames which hold an image blur correction lens group and are slidable in first and second directions orthogonal to the optical axis. In order to drive the first lens moving frame, the first coil, the first magnet that is magnetized on one side and is arranged to face the first coil, and the first magnet are held. A first actuator having a substantially U-shaped first yoke, and a second coil for driving the second lens holding frame;
A second actuator having a second magnet, which is magnetized on one side and is arranged to face the second coil, and a substantially U-shaped yoke holding the second magnet; 1. A lens mirror having an image blur correction device including a second lens moving frame and a fixed frame holding a first and second actuator and having a concave portion in a portion surrounded by the first and second actuators. A stepping motor with an encoder for moving the second lens group in the optical axis direction in a concave portion of the fixed frame, wherein the polarities of the first and second magnets are opposite when viewed from the optical axis center. It is characterized by being arranged as described above.

Also, the lens barrel of the present invention holds the image blur correction lens group, and is slidable in first and second directions perpendicular to the optical axis at different heights in the optical axis direction. , A second lens moving frame, first and second actuators for driving the first and second lens moving frames, and a diaphragm driving actuator, and an optical axis image of the first and second actuators. An aperture driving actuator is disposed on the optical axis object side of the actuator disposed on the surface side.

Further, the lens barrel of the present invention holds the image blur correction lens group, and is slidable in first and second directions perpendicular to the optical axis at different heights in the optical axis direction. A lens barrel having an image blur correction device including a second lens moving frame, and first and second actuators for driving the first and second lens moving frames, wherein the first lens moving A first lens moving frame disposed integrally with the frame to detect a position of the first lens moving frame;
And a second light-emitting unit for detecting the position of the second lens moving frame, which is disposed integrally with the second lens moving frame.
And a substrate on which the light receiving units of the first and second position detecting units are disposed, and the light emitting units of the first and second position detecting units are viewed from the optical axis direction. It is characterized by being arranged at substantially the same height.

The lens barrel of the present invention holds first and second lens moving frames which hold an image blur correction lens group and are slidable in first and second directions orthogonal to the optical axis. A first electric component which is integrated with the first lens moving frame and serves as a driving means and a position detecting means for the first moving frame; and a driving means for the second lens moving frame which is integrated with the second lens moving frame. And a second electric component serving as position detecting means, a fixed frame for slidably fixing the first and second lens moving frames, and a first flexible print electrically connected to the first electric component. Cable and second
A lens barrel provided with an image blur correction device including a second flexible printed cable electrically connected to the first electrical component, wherein one end of the first flexible printed cable is connected to a light source of a first driving unit. One end of the second flexible printed cable is fixed to the first lens moving frame on the opposite side of the axis center and on the same side of the second driving means, and the optical axis of the first and second driving means is The other end of the first and second flexible printed cables is fixed to the second lens moving frame on the opposite side of the center, and the other ends of the first and second flexible printed cables are substantially parallel to the sliding direction of the first moving frame. The second moving means is fixed to the fixed frame on the opposite side of the optical axis center.

[0025]

DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) A lens barrel according to a first embodiment of the present invention will be described below with reference to FIGS. FIG. 1 is a schematic perspective view of a lens barrel equipped with a linear actuator according to a first embodiment and a stepping motor with an encoder, FIG. 2 is a conceptual diagram showing the flow of leakage magnetic flux of the linear actuator, and FIG. FIG. 4 shows resistance change rate characteristics, and FIG.
FIG. 5 is a conceptual view showing a flow of a leakage magnetic flux to a stepping motor with an encoder.

The focus lens moving frame 31 holds the focus lens group 30 and is disposed in parallel with the optical axis. The optical axis moves along guide poles 32a and 32b whose both ends are fixed to a lens barrel (not shown). It is configured to be slidable in the direction (X direction). This focus lens moving frame 3
The stator 34 of the linear actuator 33 for driving the actuator 1 in the optical axis direction includes a main magnet 35 magnetized perpendicular to the driving direction (X direction) and a U-shaped main yoke 36.
And a plate-shaped side yoke 37, which is provided in the lens barrel. Further, the magnetic circuit 38 including the stator 34 is configured to be left-right symmetric when viewed from the driving direction, and substantially left-right symmetric also in the driving direction (X direction). On the other hand, the coil 40, which is a component of the mover 39 of the linear actuator 33, is fixed to the focus lens moving frame 31 so as to have a predetermined gap with the magnet 35, and the coil 40 is orthogonal to the magnetic flux generated by the magnet 35. By passing an electric current through 40, the focus lens moving frame 31 is driven in the optical axis direction.

In order to control the position of the focus lens moving frame 31, a magnetic sensor 41 is provided on a fixed lens barrel as a position detecting device. In addition, it is provided at the center of symmetry of the magnetic circuit 38 as viewed from the driving direction. On the other hand, a magnetic scale 42 having N poles and S poles alternately magnetized is attached to the movable focus lens moving frame 31 so as to face the detection surface of the magnetic sensor 41 at a predetermined distance. I have. The magnetic sensor 41 is a two-phase magnetoresistive sensor composed of MR elements 43a and 43b made of a ferromagnetic thin film.
3b are provided in the drive direction at an interval of 1/4 of the magnetization pitch between the N pole and the S pole of the magnetic scale 42.
The direction of the current flowing through the elements 43a and 43b is
The magnetic sensor 41 and the magnetic scale 42 are respectively arranged in a direction perpendicular to the magnetization direction of No. 5.

Next, a position detecting method using the magnetic sensor 41 will be described. The directionality of the magnetoresistance change shown in FIG. 3 is as follows for a magnetic field in a direction (Y direction) perpendicular to the current direction of the MR elements 43a and 43b and perpendicular to the detection surface.
Although the resistance value hardly changes, the MR elements 43a, 43
b in a direction perpendicular to the current direction and parallel to the detection surface (X
(Direction), the resistance value changes greatly, and further, the resistance value changes slightly in a direction (Z direction) magnetic field parallel to the current direction of the MR elements 43a and 43b. . From this characteristic, when the position of the magnetic scale 42 having the magnetization pattern shown in FIG. 4 changes with respect to the magnetic sensor 41, the MR elements 43a, 43b correspond to the sinusoidal magnetic field intensity change pattern generated in the X direction. Changes the resistance value. Here, the phase in the Y direction is also 1 in the X direction.
Although a sinusoidal magnetic field intensity change pattern different by 80 ° occurs, the resistance values of the MR elements 43a and 43b hardly change due to the above characteristics. Therefore, the MR elements 43a,
Assuming that the voltage applied to 3b is an output signal, the output signal has two sinusoidal waveforms having a phase difference of 90 °.
The signal processing circuit (not shown) modulates and interpolates the two signal waveforms, thereby detecting the position and the driving direction of the lens moving frame 31. Based on the data, the control circuit (not shown) uses the focus lens group 30. Can be controlled with high precision.

However, in order to realize a highly accurate linear actuator, it is necessary to suppress a disturbance magnetic field jumping into the magnetic sensor 41. In the linear actuator 33, if there is a disturbance magnetic field in the optical axis direction (X direction), the signal waveform is offset because the disturbance magnetic field is superimposed on the signal of the sinusoidal magnetic field strength change pattern, so that the output signal waveform is changed. Distortion and position detection errors increase. Furthermore, in the direction perpendicular to the optical axis (Z direction), although the sensitivity of the magnetoresistance change is small, there is a problem that the magnetoresistance change rate decreases and the sensitivity of the MR element decreases.

For this reason, it is necessary to prevent the linear actuator 33 from being affected by a disturbance magnetic field in the X direction and the Z direction, particularly from the main magnet 35.

Therefore, as described above, the leakage magnetic flux is reduced by disposing the magnetic sensor 41 at the center of the magnetic circuit 38. That is, as shown in FIG. 2A, the MR elements 43a and 43b have a characteristic that the magnetoresistance changes in the X direction and the Z direction. Therefore, since the magnetic circuit 38 is configured to be substantially symmetrical in the driving direction (X direction), the leakage flux in the X direction of the magnetic sensor 41 located at the center of the symmetry has a very small value. Further, as shown in FIG. 2 (b), the magnetic circuit 38 is formed substantially symmetrically as viewed from the driving direction, so that the magnetic flux in the Z direction of the magnetic sensor 41 located at the center of the symmetry becomes small. . As described above, the leakage magnetic flux can be reduced by optimizing the arrangement position of the magnetic sensor 41.

Next, a stepping motor 47 with an encoder for moving the zoom lens group 45 in the optical axis direction will be described.

Stepping motor 47 with encoder
Is a stepping motor 48 and a lead screw unit 4 provided integrally with a rotation shaft of the stepping motor.
9, a sensor magnet 50 attached to the rotating shaft of the stepping motor and having N and S poles alternately magnetized in the circumferential direction, and a magnetic sensor for angle detection fixed and arranged opposite to the sensor magnet 50 51. In FIG. 1, the sensor magnet 50 and the magnetic sensor 51 are provided with a cover 51a for fixing the magnetic sensor 51.
It is covered with. A screw member 52 engaged with the zoom lens moving frame 46 holding the zoom lens group 45 is screwed into the lead screw portion 49. Accordingly, the rotation of the lead screw portion 49 causes the zoom lens group 45 to move linearly in the direction indicated by the arrow a. The CPU (not shown) of the stepping motor system with the encoder is a magnetic sensor 5
The angle information and the electric phase angle information of the rotation axis are calculated based on the angle and the electric phase counter value output by step 1. Then, the CPU calculates a drive command value based on the angle information and the electric phase angle information, and controls the stepping motor 47 with the encoder by supplying a drive current with a driver.

However, like the magnetic sensor 41 of the linear actuator 33, the magnetic sensor 51 of the encoder-equipped stepping motor 47 is affected by a disturbance magnetic field, causing output distortion of the magnetic sensor 51 and deteriorating the actuator performance. . The limit value of the magnitude of the disturbance magnetic field is about 10 gauss in the magnetic sensor 41 of the linear actuator 33, but the magnetic sensor 51 of the stepping motor 47 with the encoder has a cylindrical sensor magnet 50 and a magnetic sensor Since the surface may be flat, it is even smaller than the limit value of the disturbance magnetic field of the linear actuator 33. In addition, with respect to the stepping motor 47 with the encoder, the influence of the disturbance magnetic field from the magnet 48a of the stepping motor 48 is small, but since the lens barrel is downsized, the distance between the components and the linear actuator 33 is small. In particular, the linear actuator 33 is easily affected by the main magnet 35. Therefore, the stepping motor 47 with the encoder also needs to adopt a configuration in which the magnetic sensor 51 is disposed at a position that is not easily affected by a disturbance magnetic field.

In the stepping motor 47 with the encoder, when the magnetic sensor 51 is provided at the position shown in FIG. 5, the tangential direction (Z
Direction) and the direction of the current flowing through the magnetic sensor 51 (X direction)
It is necessary to suppress the influence of the disturbance magnetic field in the two directions. Therefore, the magnetic sensor 51 of the stepping motor 47 with the encoder is provided based on the following principle.
Since the magnetic circuit 38 of the linear actuator 33 is configured to be left-right symmetric when viewed from the driving direction, the leakage magnetic flux in the Z direction at the magnetic sensor 51 located at the center of the symmetry is substantially zero. Similarly, since the magnetic circuit 38 is configured substantially symmetrically in the X direction, the leakage magnetic flux in the X direction of the magnetic sensor 51 located at the center of the symmetry becomes substantially zero. Therefore, since the magnetic sensor 51 of the stepping motor 47 with the encoder is not affected by the disturbance magnetic field, a highly accurate actuator system can be realized.

As described above, according to the present embodiment, instead of a system using a conventional stepping motor, a system using a stepping motor with an encoder for zooming and a linear actuator for focusing simultaneously is constructed. Can be. Therefore, as for the zoom function, since the feed rate can correspond to about 30 to 2000 pps, an ultra-high-speed or an ultra-low-speed zoom becomes possible.
A highly functional lens barrel and a video camera using the same can be provided. Furthermore, since the closed-loop control can be performed to control the rotation angle and the torque, power consumption and noise can be reduced. For the focus function, in addition to high-speed response, high resolution and high accuracy are obtained using a magnetic sensor,
Excellent focus characteristics can be realized. Furthermore, unlike the conventional method, the method of reducing the disturbance magnetic field does not require the use of shield components or the like, and merely devises the arrangement of the magnetic sensor, thereby reducing the cost and further increasing the installation space. An increase in the size of the tube can be suppressed, and a lens barrel that is small and lightweight can be provided.

It is needless to say that the same effect can be obtained even if the polarity of the magnetization of the main magnet of the linear actuator according to the present embodiment is opposite to that shown in FIGS.

As the linear actuator of the present embodiment, the magnetic sensor is provided on the fixed lens barrel and the magnetic scale is provided on the movable lens moving frame. It goes without saying that a similar effect can be obtained even if a magnetic sensor is provided on the movable lens moving frame.

In the embodiment of the present invention, a magneto-resistive effect type magnetic sensor using an MR element is used. However, any type of sensor that outputs an output signal corresponding to the strength of the magnetic force can be used. Applicable to all magnetic sensors. (Second Embodiment) Next, a second embodiment of the present invention will be described with reference to FIGS. FIG. 6 shows the second
FIG. 7 is a schematic perspective view of a lens barrel equipped with an image blur correction device and a linear actuator according to the embodiment, FIG. 7 is a perspective view of a main part of the image blur correction device, and FIG. 8 is a block diagram of an image blur correction circuit. The same reference numerals are given to those described so far, and the description thereof will be omitted.

The lens group 1 for correcting image blur during photographing includes:
It is fixed to a holding frame 2 movable in the Z direction in FIG.
Hereinafter, the holding frame 2 is referred to as a pitching movement frame. The pitching movement frame 2 is configured to be slidable via two pitching shafts 3a and 3b by providing a bearing 2a and a detent 2b on the opposite side. An electromagnetic actuator 6 is provided below the pitching movement frame 2.
p is arranged. This electromagnetic actuator 6p
It is composed of a coil 7p attached to the pitching movement frame 2, a magnet 8p and a yoke 9p attached to a fixed frame 10 described later. The yoke 9p is provided with protrusions 9pa on both sides thereof, and the fixed frame 10 is provided with fitting holes 10pa capable of fitting with the protrusions and 9pa in substantially the same direction as the sliding direction of the pitching moving frame 2. I have. Therefore, when the yoke 9p is fixed to the fixing frame 10, it is not necessary to perform bonding or the like. The magnet 8p has two poles magnetized on one side and is fixed to a U-shaped yoke 9p that is open on one side.

On the optical axis image plane side of the pitching movement frame 2, a frame 4 for moving the lens group 1 for correcting image blur in the Y direction.
Is attached. Hereinafter, the holding frame 4 is referred to as a yawing moving frame. On the optical axis object side of the yawing movement frame 4, fixing portions 4c and 4d for fixing both ends of two pitching shafts 3a and 3b for sliding the pitching movement frame 2 described above in the Z direction are provided. I have. Similarly, the yaw moving frame 4 is configured to be slidable via two yaw shafts 5a and 5b by providing a bearing 4a and a detent 4b on the opposite side.
The two yawing shafts 5a and 5b are fixed to fixing portions 10c and 10d of a fixing frame 10 provided on the optical axis image plane side of the yawing moving frame 4. On the left side of the yawing movement frame 4, an electromagnetic actuator 6y is arranged. The electromagnetic actuator 6y includes a coil 7y attached to the yawing moving frame 4, a magnet 8y attached to the fixed frame 10, and a yoke 9y. Similarly, the yoke 9y is provided with protrusions 9ya on both sides thereof, and the fixed frame 10 is provided with fitting holes 10ya capable of fitting the protrusions and 9ya in substantially the same direction as the sliding direction of the yawing moving frame 4. Is provided. Therefore, when the yoke 9y is fixed to the fixing frame 10, it is not necessary to perform bonding or the like. The magnet 8y has two poles magnetized on one side and is fixed to a U-shaped yoke 9p which is open on one side.

Therefore, when a current flows through the coil 7p of the pitching movement frame 2, the magnet 8p and the yoke 9p
Thus, an electromagnetic force is generated in the Z-axis direction. Similarly,
When a current is applied to the coil 7y of the yawing movement frame 4,
An electromagnetic force is generated in the Y-axis direction by the magnet 8y and the yoke 9y. Thus, the two electromagnetic actuators 6
The lens group 1 for correcting image blur is driven in two directions substantially perpendicular to the optical axis by p and 6y.

Next, the position detecting section will be described. The detection unit 11p of the pitching movement frame 2 in the Z direction
p (for example, LED), slit 13p and PSD substrate 1
5 includes a light receiving element 14p (PSD). Similarly, the detection unit 11y of the yawing movement frame 4 in the Y direction includes the light emitting element 12y, the slit 13y, and the PS
It is composed of a light receiving element 14y attached to the D board 15. The light emitting elements 12p and 12y have slits 13p,
The light projected through 13y and passed through the slits 13p and 13y enters the light receiving elements 14p and 14y. Therefore, the movement of the image blur correction lens group 1 is controlled by the light receiving element 14.
The movement of light incident on p and 14y is obtained. Light receiving element 14
p and 14y output the position information of the light incident on the light receiving surface as two current values, the output values are calculated, and the position is detected.

Next, a flexible print cable for connecting the fixed moving frame 10 with the pitching moving frame 2 and the yawing moving frame 4 will be described.

A flexible printed cable 16 is mounted on the upper surface of the pitching movement frame 2 so as to surround the correction lens group 1 and is electrically connected to the coil 8p and the light emitting element 12p. It is fixed to be substantially orthogonal to Z. On the other hand, the other end 16 a of the flexible printed cable 16 is fixed to the side surface 10 e of the fixed frame 10 so as to be substantially parallel to the sliding direction Z of the pitching moving frame 2. Therefore, the coil 7p and the light emitting element 12p are respectively connected to a circuit for supplying a drive current (not shown). Similarly, the yawing movement frame 4
A flexible printed cable 17 is attached to the side surface of the device, and is electrically connected to the coil 7y and the light emitting element 12y, and is fixed at a portion 17b so as to be substantially parallel to the sliding direction Y. On the other hand, the other end 17a of the flexible printed cable 17 is attached to the side surface 10e of the fixed frame 10,
The pitching movement frame 2 is fixed so as to be substantially parallel to the sliding direction Z. Therefore, the coil 7y and the light emitting element 1
2y are connected to circuits for supplying a drive current (not shown). The above components constitute the shift unit 20 for image blur correction.

Further, the shift unit 20 has a configuration as shown in FIG. 7 showing an assembled state of the shift unit in order to reduce the size in the lens radial direction. The pitching movement frame 2 and the yawing movement frame 4 have different heights in the optical axis direction, and the pitching movement frame 2 is provided on the optical axis object side. Further, the yoke 9y of the yaw shift actuator 6y is configured to overlap with the yoke 9y on the optical axis image side of the bearing 2a of the pitching movement frame 2 as viewed from the optical axis direction. Therefore, the size of the shift unit 20 in the radial direction, that is, the width B can be reduced, which leads to downsizing of the shift unit 20.

The operation of the thus constructed lens barrel will be described below.

First, camera shake acting on a video camera incorporating an image blur correction device is detected by two angular velocity sensors 21 (not shown) arranged at 90 degrees. The output obtained by the angular velocity sensor 21 is integrated over time. Then, it is converted into the camera shake angle, and the image blur correction lens group 1
Is converted to target position information. In order to move the image blur correction lens group 1 in accordance with the target drive position information, the servo circuit 22 calculates a difference between the target position information and the current position information of the image blur correction lens group 1, and calculates a difference between the target position information and the current position information of the image blur correction lens group 1.
Transmit the signal to p, 6y. Electromagnetic actuator 6p,
6y drives the image blur correction lens group 1 based on this signal. The operation of the image blur correction lens group 1 is based on the position detection unit 1
1p, 11y, which is detected and fed back, can correct the image blur generated in the video camera.

Regarding the driving of the yawing movement frame 4, the electromagnetic actuator 6y, which has been instructed by the drive circuit, passes through the flexible printed cable 17 to the coil 7y.
When a current flows in the Y direction, a force acts in the Y direction to drive the yawing movement frame 4 in the Y direction. Regarding the driving of the pitching movement frame 2, when a current flows through the flexible printed cable 16 to the coil 7p through the flexible printed cable 16, the electromagnetic actuator 6p exerts a force in the Z direction, causing the pitching movement frame 2 to move in the Z direction. Drive in the direction. Therefore,
The correction lens group 1 can be arbitrarily moved in a plane orthogonal to the optical axis by the yawing movement frame 4 and the pitching movement frame 2, so that image blur caused by camera shake can be corrected.

As described above, according to the present embodiment, in the lens barrel equipped with the shift unit for image blur correction, there are two types of pitching and yawing for moving the correction lens group in a direction orthogonal to the optical axis. The moving frames are arranged at different heights with respect to the optical axis direction, and when viewed from the optical axis direction, the actuator section of the yawing moving frame is arranged so as to overlap with the pitching moving frame. Since the size of the lens unit can be reduced, the size of the lens barrel equipped with the shift unit can be reduced. Third Embodiment Next, a third embodiment of the present invention will be described with reference to FIGS. FIG. 9 is a schematic perspective view of a lens barrel equipped with an image blur correction device and a linear actuator according to the third embodiment, FIG. 10 is a diagram showing an arrangement of a yoke of the actuator, and FIG. 11 is a shift actuator for the image blur correction device. FIG. 4 is a diagram showing a flow of a leakage magnetic flux of FIG. The same reference numerals are given to those described so far, and the description thereof will be omitted.

Shift unit 20 according to the embodiment of the present invention
Are the same as those described in the second embodiment.
In FIG. 9, the fixing frame 10 of the shift unit 20 is omitted for easy understanding. Further, the pitching and yawing magnets 8 of the shift unit 20 are used.
The directions of p, 8y and the magnetization of the magnet 35 of the linear actuator 33 are as shown in the figure. The pitching movement frame 2 and the yawing movement frame 4 of the shift unit 20 are arranged at different heights in the optical axis direction, and the pitching movement frame 2 is arranged on the optical axis object side. Yoke 9 constituting pitching actuator 6p
On the optical axis image plane side of p, a main yoke 36 and a side yoke 37 of a linear actuator 33 for driving the focus lens group 30 described in the first embodiment in the optical axis direction are arranged. . FIG. 10 is a top view showing the arrangement of the shift unit 20 and the linear actuator 33. Although the magnetic sensor 41 is used as the position detecting means of the linear actuator 33, the sensor output is distorted by the influence of the disturbance magnetic field, and the performance of the actuator is deteriorated. Therefore, in order to arrange the shift unit 20 and the linear actuator 33 in one lens barrel, the linear actuator 3
3 needs to be reduced. This leakage magnetic flux can be reduced by increasing the distance between the shift unit 20 and the linear actuator 33. However, since this leads to an increase in the size of the lens barrel, it is necessary to reduce the size in the optical axis direction. Is the shift unit 20
It is necessary to reduce the leakage magnetic flux while making the linear actuator 33 and the linear actuator 33 adjacent to each other. Therefore, a method for reducing the noise will be described.

The magnetic sensor 4 of the linear actuator 33
As described in the first embodiment, the installation position of No. 1 is in the optical axis direction (X direction) and its orthogonal direction (Z direction).
In the two directions (directions), the magnetic flux is reduced by disposing the magnetic sensor 41 at the center position of the magnetic circuit 38 where the influence of the disturbance magnetic field is almost zero. In this state, the magnet 8 of the pitching actuator 6p is used.
When the magnetization of p is as shown in FIG. 9, a leakage magnetic flux as shown in FIG. 11 is generated at the position of the magnetic sensor 41 due to the influence of the pitching actuator 6p. The position of the magnetic sensor 41 described in the first embodiment is represented by b in the Z-axis direction.
Was located in the position. (Position of ○ mark) However, due to the effect of the pitching actuator 6p, −
Since the leakage magnetic flux is generated in the Z direction, the leakage magnetic flux jumps into the magnetic sensor 41 at the position of the mark. In the case where the main magnet 35 of the linear actuator 33 is magnetized as shown in FIG. 9, a leakage magnetic flux is generated as shown by a white arrow.
Shift by b in the direction to the position indicated by the mark. as a result,
Since the magnetic flux leakage in the Z-axis direction from the pitching actuator 6p and the linear actuator 33 is cancelled, the amount of diving into the magnetic sensor 41 becomes almost zero. In the X direction, there is no influence of the pitching actuator 6p. Further, since the position of the magnetic sensor 41 in the X direction is not changed, the magnetic sensor 41 is located at the magnetic center in the X direction in the magnetic circuit 38 of the linear actuator 33, so that there is no influence from the linear actuator. The yawing actuator 6
The influence of the leakage magnetic flux from y is small compared to the pitching actuator 6p because the distance is large.

As described above, according to the present embodiment, the linear actuator can be mounted by arranging the lens barrel on which the shift unit for correcting camera shake is mounted so as to eliminate the influence of the disturbance magnetic field. . Therefore, by driving the focus lens group by the linear actuator, high resolution and high accuracy can be obtained by using the magnetic sensor in addition to high-speed response, so that excellent focus characteristics can be realized. Furthermore, unlike the conventional method, only the location of the magnetic sensor needs to be devised to reduce the leakage magnetic flux, and there is no need to use shield parts, so the cost is reduced, and the lens barrel is increased due to the increased installation space. Can be prevented from becoming larger. Further, the pitching movement frame and the yawing movement frame of the shift unit are configured to have different heights in the optical axis direction, and the pitching actuator disposed on the optical axis object side is provided on the optical axis image plane side with a focus lens driving side. By arranging the linear actuator, it is possible to shorten the width direction while effectively using the space in the optical axis direction, so that the lens barrel can be downsized.

In the present embodiment, the magnetizing polarities of the pitching actuator of the shift unit and the magnets of the linear actuator are as shown in FIG. 9, but the polarities of the magnetizing are reversed. However, it goes without saying that a similar effect can be obtained. (Fourth Embodiment) Next, a fourth embodiment of the present invention will be described with reference to FIGS. FIG.
Is a schematic perspective view of a lens barrel equipped with an image blur correction device and a stepping motor with an encoder according to a fourth embodiment, and FIG. 13 is a front view of the lens barrel. The same reference numerals are given to those described so far, and the description thereof will be omitted.

The zoom lens group 45 is held by a zoom lens moving frame 46. A screw member 52 is engaged with the sleeve portion 46a of the lens moving frame 46, and the screw member 52 is screwed to a lead screw portion 49 of an output shaft of the stepping motor 47 with the encoder. Therefore, by rotating the stepping motor 47 with the encoder, the zoom lens moving frame 46 can be moved in the optical axis direction along the guide poles 32a and 32c. Stepping motor 47 with encoder
The recess 10a is provided in the fixed frame 10 of the shift unit 20 in order to dispose it in a position that does not overlap with the arrangement area of the shift actuators 6p and 6y of the shift unit 20 when viewed from the optical axis direction. The recess 10a is located between the yokes 9p and 9y of the shift actuators 6p and 6y for pitching and yawing of the shift unit 20. The shift unit 20 moves the yoke 9 with respect to the center of the optical axis.
The width of the ep and ey portions with p and 9y is the position detection unit 11
Since it is larger than the dp and dy portions with p and 11y,
Effective use of the ep and ey portions leads to how the size of the lens barrel from the optical axis center can be reduced. Further, the components dp and dy on the opposite side are not provided with the components of the lens barrel, but are formed in a substantially arc shape as shown in FIG. Since the outer shape of the video camera can be made substantially arc-shaped, a video camera excellent in design can be realized. Therefore, the stepping motor 47 with the encoder is arranged such that the threaded portion of the screw member 52 of the stepping motor 47 with the encoder is located in the concave portion 10a of the fixed frame 10. Thus, the stepping motor 47 can be arranged at a position close to the optical axis without interfering with the shift unit 20, and the size of the lens barrel in the radial direction can be reduced.

As described above, according to the present embodiment, the concave portion is provided in the shift lens unit, and the stepping motor for zooming is disposed in the concave portion. Even in a lens barrel equipped with an image blur correction device equipped with two shift actuators for driving a correction lens group in two directions, a zoom stepping motor can be arranged near the center of the optical axis. In addition, it is possible to reduce the size of the lens barrel in the radial direction.

In the description of the present embodiment, a stepping motor with an encoder has been described as an actuator for driving the zoom lens group. However, it goes without saying that the same effect can be obtained by using a normal stepping motor. (Fifth Embodiment) Next, a fifth embodiment of the present invention will be described with reference to FIGS. FIG.
FIG. 15 is a diagram showing the flow of the leakage magnetic flux of the image blur correction device according to the fifth embodiment, and FIG. 15 is a diagram in which a linear actuator is added to the lens barrel shown in FIG. The same reference numerals are given to those described so far, and the description thereof will be omitted.

Regarding the embodiment of the present invention, the shift unit 20 and the stepping motor 47 with the encoder
Is the same as that described in the fourth embodiment of the present invention, in which actuators for moving the image blur correction lens group 1 in two directions orthogonal to the optical axis are arranged, and the pitching and yawing actuators 6p and 6y York 9p, 9
A stepping motor 47 with a zoom encoder is arranged at a position sandwiched by y.

In the first embodiment of the present invention, the magnetic sensor 51 is connected to the magnetic circuit 38 of the linear actuator 33 in order to reduce the influence of a disturbance magnetic field on the magnetic sensor 51 on the stepping motor 47 with the encoder.
However, by adding the shift unit 20, that is, the pitching and yawing actuators 6p and 6y, it is necessary to take measures against leakage magnetic flux from these two actuators.
Therefore, a method for reducing the noise will be described.

As shown in FIG. 19, the magnet 8p of the pitching actuator 6p has an N pole on the upper side and an S pole on the lower side when viewed from the optical axis object side in a direction perpendicular to the optical axis.
It is magnetized to be a pole. Further, the magnet 8y of the yawing actuator 6y is magnetized such that the left side has an N pole and the right side has an S pole with respect to the direction orthogonal to the optical axis, when viewed from the optical axis object side. That is, the pitching and the yawing are arranged such that the polarities are opposite when viewed from the optical axis center. Therefore, in the magnetic circuit composed of the yoke and the magnet, the direction of the magnetic flux flows in the pitching and the yawing by reversing the polarity of the magnet. As a result, the direction of the flow of the leakage magnetic flux is also reversed.

It has been described in the first embodiment that the magnetic sensor 51 of the stepping motor 47 with the encoder needs to reduce the leakage magnetic flux in the X direction and the Z direction. Therefore, first, the flow of the leakage magnetic flux in the X direction will be described in detail. Yawing actuator 6
The leakage magnetic flux of y flows in the direction of arrow j at the position of the magnetic sensor 51 of the stepping motor 47 with the encoder shown in FIG. Conversely, the leakage magnetic flux of the pitching actuator 6p is at the position of the magnetic sensor 51 of the stepping motor 47 with the encoder shown in FIG.
It flows in the direction of arrow k. Therefore, at the position of the magnetic sensor 51, the flow of the leakage magnetic flux of the pitching and yawing actuators 6p and 6y is in the opposite direction, so that the leakage magnetic flux is canceled, and the amount of diving into the magnetic sensor 51 can be reduced. On the other hand, in the Z direction, since there is no influence of the leakage magnetic flux, the amount of jump into the magnetic sensor 51 is small. Therefore, in two directions of X and Z,
Since the influence of the leakage magnetic flux can be eliminated, distortion of the output of the magnetic sensor can be eliminated, and highly accurate position detection accuracy can be obtained.

Further, the stepping motor 47 with encoder, the linear actuator 33 and the shift unit 20 are combined with the stepping motor 47 with encoder and the linear actuator 3 described in the first embodiment.
3 and the shift unit 20 and the linear actuator 33 described in the third embodiment, the influence of the disturbance magnetic field is reduced.
As shown in FIG. 15, it is possible to dispose them in one lens barrel. In FIG. 15, the fixing frame 10 is omitted for easy understanding.

As described above, according to the present embodiment, in the lens barrel equipped with the shift unit for performing the camera shake correction, in addition to the improvement in the performance of the camera shake correction, the feed speed is increased by using the stepping motor with the encoder. Can handle up to about 30 to 2000 pps, so that ultra-high-speed or ultra-low-speed zoom is possible, and a highly functional lens barrel and a video camera using the same can be provided. It also performs closed loop control,
Since the torque can also be controlled, low power consumption and low noise can be realized. Furthermore, unlike the conventional method, it is not necessary to use a shield component or the like for the reduction of the leakage magnetic flux, so that it is possible to reduce the cost and further suppress the enlargement of the lens barrel accompanying an increase in the installation space.
A compact and lightweight lens barrel can be provided.

Further, as described in the fourth embodiment, the magnetic sensor of the stepping motor with the encoder is arranged substantially at the center of the magnetic circuit of the linear actuator, and the magnetic sensor of the fifth embodiment is described. As described above, by disposing the linear actuator on the optical axis image plane side of the pitching actuator of the shift unit,
A linear actuator for driving a focus lens can also be mounted on a lens barrel equipped with a shift unit and a stepping motor with an encoder. Therefore, as a result of using a magnetic sensor in addition to high-speed response,
By obtaining high resolution and high accuracy, excellent focus characteristics can be realized.

In this embodiment, the magnetizing polarities of the pitching and yawing actuators of the shift unit and the magnets of the linear actuator are as shown in FIG. 9, but the polarities of the magnetizing are reversed. However, it goes without saying that a similar effect can be obtained. (Sixth Embodiment) Next, a sixth embodiment of the present invention will be described with reference to FIGS. FIG.
FIG. 17 is a view showing a lens barrel equipped with an image blur correction device, a stepping motor with an encoder and an iris unit according to a sixth embodiment, FIG. 17 is a front view of the lens barrel, and FIG. 18 is a perspective view of the lens barrel. is there. The same reference numerals are given to those described so far, and the description thereof will be omitted.

Shift unit 20 according to the embodiment of the present invention
Are the same as those described in the second embodiment.
The pitching movement frame 2 and the yawing movement frame 4 of the shift unit 20 are at different heights in the optical axis direction, and the yawing movement frame 4 is disposed on the optical axis image plane side. Further, on the optical axis object side of the yawing actuator 6y,
The meter 61 of the aperture unit 62 is provided. Therefore, by arranging the meter 61 of the aperture unit 62 in this way, the stepping motor 47 for zoom
And the shift unit 20 does not interfere. As described above, the components described in the first to fifth embodiments of the present invention, namely, the shift unit 20 for correcting image blur, the stepping motor 47 with the encoder, the linear actuator 33, and the aperture unit 62 are used. One actuator can be disposed in one lens barrel as shown in FIG.
A highly functional lens barrel can be realized. (Seventh Embodiment) Next, a seventh embodiment of the present invention will be described with reference to FIGS. FIG. 19 is a diagram illustrating a PSD substrate of a lens barrel according to a seventh embodiment, and FIG. 20 is a diagram illustrating an arrangement of LEDs and PSDs of the lens barrel. The same reference numerals are given to those described so far, and the description thereof will be omitted.

Shift unit 20 according to the embodiment of the present invention
Are the same as those described in the second embodiment.
Light emitting elements 12p and 12y for detecting the positions of the pitching movement frame 2 and the yawing movement frame 4 of the shift unit 20
The light receiving elements 14p and 14y need to be accurately positioned and fixed in order to improve the position detection accuracy. Therefore, as shown in FIG. 19, the light receiving elements 14p and 14y were positioned and fixed on the same PSD substrate 15. Further, in order to effectively use the space in the optical axis direction, the pitching movement frame 2 and the yawing movement frame 4 are arranged at different heights. However, the pitching and yawing light emitting elements 12p,
The slits 13p and 13y provided with 12y are configured to have the same height. Therefore, in both pitching and yawing, the slits 13p, 13y
And the light receiving elements 14p and 14y have the same distance c, the light emitting elements 12p and 12y emit light, and the light receiving element 1p
Since the amount of light reaching the light receiving surface of 4p and 14y is the same, the same position detection accuracy can be obtained.

As described above, according to the present embodiment, in a lens barrel equipped with a shift unit for performing camera shake correction, the height of the pitching movement frame and the yawing movement frame in the optical axis direction is changed. One actuator can be mounted compactly. Furthermore, the two light receiving elements can be arranged on the same substrate by arranging the slits of the light emitting elements at the same height despite the different heights of the moving frames. Therefore, since the positioning accuracy of the light receiving element can be improved, the position detection accuracy can be improved. Further, since the substrate on which the light receiving element is mounted can be easily attached to the fixed frame, the assemblability can be improved. (Eighth Embodiment) Next, an eighth embodiment of the present invention will be described with reference to FIGS. FIG.
21 is a front view of yawing of the image blur correction device for the lens barrel according to the eighth embodiment, and FIG. 22 is a front view of pitching of the image blur correction device. The same reference numerals are given to those described so far, and the description thereof will be omitted.

In the embodiment of the present invention, the shift unit 20 is the same as that described in the second embodiment. In the shift unit 20, the flexible printed cables 16 and 17 that connect the pitching movement frame 2 and the yawing movement frame 4 to the fixed frame 10 will be described.

One end 16b of the flexible printed cable 16 of the pitching movement frame 2 is on the opposite side of the center of the optical axis from the pitching actuator 6p and on the same side as the yawing actuator 6y. It is fixed to be substantially orthogonal to Z.
That is, the first lens moving frame described in the claims corresponds to the pitching moving frame 2. On the other hand, one end 17b of the flexible printed cable 17 of the yawing movement frame 4 is opposite to the pitching actuator 6p and opposite to the yawing actuator 6y with respect to the optical axis center. And is fixed substantially in parallel. That is, the second lens moving frame described in the claims corresponds to the yawing moving frame 4. And flexible printed cable 1
The other ends 16a and 17a of the fixing frames 10 and 10
It is fixed to the portion so as to be substantially parallel to the sliding direction Z.

The operation of the thus-configured image blur correction device will be described below.

For driving the yawing movement frame 4, the electromagnetic actuator 6 y receiving a command from the drive circuit passes through the coil 7 y through the flexible printed cable 17.
When a current flows in the Y direction, a force acts in the Y direction to drive the yawing movement frame 4 in the Y direction. Regarding the driving of the pitching movement frame 2, the electromagnetic actuator 6p, which has received a command from the drive circuit, applies a force in the Z direction when a current flows through the coil 7p through the flexible printed cable 16, and moves the pitching movement frame 2 in the Z direction. Drive. On this occasion,
The flexible printed cables 16 and 17 for pitching and yawing are connected to the R section 10 provided on the fixed frame 10.
It will bend along f. Therefore, the pitched flexible printed cable 16 bends between one end 16b fixed to the pitching movement frame 2 and the other end 16a fixed to the fixed frame 10. Similarly, the yawed flexible printed cable 17 bends between one end 17b fixed to the yawing moving frame 4 and the other end 17a fixed to the fixed frame 10. Therefore, both of the flexible printed cables 16, 17 are
Since a longer movable portion can be formed in this limited space, the reactive force of the flexible printed cables 16 and 17 is less likely to be generated, which leads to a reduction in load.

As described above, according to the present embodiment, the length of the movable portion of the flexible printed cable of the yawing moving frame and the pitching moving frame can be maximized within a limited space. Therefore, the effect of the reaction force generated by the flexure of the flexible printed cable,
It is possible to minimize both the yawing movement frame and the pitching movement frame, thereby suppressing deterioration of control characteristics. As a result, it is possible to provide an excellent image blur correction device having a high degree of suppression of image blur.

In this embodiment, the other end of the flexible printed cable is fixed to the fixing frame substantially in parallel with the sliding direction Z. If the print cable is regulated, a method in which the flexible print cable is bent at a fixing place in the text and fixed at another portion may be used.

[0075]

As described above, according to the lens barrel of the present invention, the lens barrel is configured by using the linear actuator using the magnetoresistive sensor and the stepping motor with the encoder, and the leakage from the linear actuator is achieved. Since the magnetic flux does not affect the magnetoresistive sensor of the stepping motor with the encoder, high speed and low power consumption can be achieved in zoom and focus lens driving. Furthermore, unlike the conventional method, there is no need to use a shield component or the like to reduce the leakage magnetic flux.
Since a reduction in cost and an increase in the size of the lens barrel due to an increase in installation space can be suppressed, a remarkable effect of being able to provide a lens barrel that is small and lightweight can be obtained.

According to the lens barrel of the present invention, in a lens barrel having an image blur correction device having an actuator for moving two actuators in a direction substantially orthogonal to each other, the two moving frames are moved in the optical axis direction. Since the lenses are arranged at different heights and are arranged so as to overlap each other when viewed from the optical axis direction, the size of the lens barrel in the width direction can be reduced. The remarkable effect that size reduction of can be achieved is obtained.

Further, according to the lens barrel of the present invention, a lens barrel having an image blur correction device having a linear actuator for driving the focus lens and an actuator for moving the two actuators in directions substantially orthogonal to each other. , The two moving frames of the image blur correction device are arranged at different heights in the optical axis direction, and the linear actuator is arranged on the optical axis image plane side of the actuator arranged on the optical axis object side, so that the size is reduced. Thus, a lens barrel equipped with three linear actuators can be realized while achieving a remarkable effect that the speed of the focus motor and the actuator of the image blur correction device can be increased and the power consumption can be reduced.

Further, according to the lens barrel of the present invention, an image blur correction device is required in which two actuators for driving the correction lens in two directions orthogonal to the optical axis need to be added as compared with a normal barrel. Even in the lens barrel described above, since the stepping motor for driving the zoom lens is disposed between the yokes of the two shift actuators, the zoom stepping motor can be disposed near the center of the optical axis. A remarkable effect is obtained that the size of the lens barrel in the radial direction can be reduced.

Further, according to the lens barrel of the present invention, the polarity of the magnets of the pitching and yawing actuators of the shift unit is reversed in the lens barrel equipped with the shift unit for correcting camera shake. Since the leakage magnetic flux to the magnetic sensor of the stepping motor can be reduced, not only can image blur correction be performed, but also ultra-high-speed or ultra-low-speed zoom can be performed. Furthermore, unlike the conventional method, it is not necessary to use a shield component or the like to reduce the leakage magnetic flux, so that it is possible to reduce the cost and further suppress the enlargement of the lens barrel due to an increase in the installation space. A remarkable effect of providing a lens barrel with an improved structure can be obtained.

Further, according to the lens barrel of the present invention, the lens barrel having the diaphragm meter for driving the diaphragm and the image blur correction device having the actuator for moving the two actuators in the direction substantially orthogonal to each other. The two moving frames of the image blur correction device are arranged at different heights in the optical axis direction, and the meter of the diaphragm is arranged on the optical axis object side of the actuator arranged on the optical axis image plane side, so that the size is reduced. While achieving this, a remarkable effect that the speed of the actuator of the image blur correction device can be increased and the power consumption can be reduced can be obtained.

According to the lens barrel of the present invention, in a lens barrel equipped with a shift unit for correcting camera shake, the light emitting element and the light receiving element, which are the means for detecting the pitching and yawing positions, are the same in the optical axis direction. By arranging at the height, a remarkable effect that the assemblability can be improved while effectively using the space can be obtained. According to the lens barrel of the eighth aspect, in the lens barrel equipped with the shift unit for performing camera shake correction, the flexible printed cable for pitching and yawing can be used effectively while maximizing the length of its movable part. Since the length can be made as long as possible, the influence of the reaction force due to the bending of the flexible printed cable can be suppressed. Therefore, a remarkable effect is obtained in that the load can be reduced and the degree of suppression of image blur can be increased.

[Brief description of the drawings]

FIG. 1 is a schematic perspective view of a lens barrel equipped with a linear actuator and a stepping motor with an encoder according to a first embodiment of the present invention.

FIG. 2 is a conceptual diagram showing a flow of a leakage magnetic flux of the linear actuator according to the first embodiment.

FIG. 3 is a diagram showing a magnetoresistance change characteristic of an MR element.

FIG. 4 is a schematic perspective view of a position detecting unit using an MR element.

FIG. 5 is a conceptual diagram showing a flow of a leakage magnetic flux to a stepping motor with an encoder according to the first embodiment.

FIG. 6 is a schematic perspective view of a lens barrel according to a second embodiment.

FIG. 7 is a perspective view of a main part of an image blur correction device according to a second embodiment.

FIG. 8 is a block diagram of an image blur correction circuit according to a second embodiment.

FIG. 9 is a schematic perspective view of a lens barrel according to a third embodiment.

FIG. 10 is a diagram showing an arrangement of a yoke of an actuator according to a third embodiment.

FIG. 11 is a diagram showing a flow of leakage magnetic flux of a shift actuator for an image blur correction device according to a third embodiment.

FIG. 12 is a schematic perspective view of a lens barrel according to a fourth embodiment.

FIG. 13 is a front view of a lens barrel according to a fourth embodiment.

FIG. 14 is a diagram showing a flow of a leakage magnetic flux of the image blur correction device according to the fifth embodiment.

FIG. 15 is a diagram in which a linear actuator is added to the lens barrel shown in FIG. 12 according to the fifth embodiment;

FIG. 16 is a diagram showing a lens barrel equipped with an image blur correction device, a stepping motor with an encoder, and an iris unit according to a sixth embodiment.

FIG. 17 is a front view of a lens barrel according to a sixth embodiment.

FIG. 18 is a perspective view of a lens barrel according to a sixth embodiment.

FIG. 19 illustrates a PSD of a lens barrel according to a seventh embodiment.
Diagram showing board

FIG. 20 illustrates an LED of a lens barrel according to a seventh embodiment.
Diagram showing the layout of the and PSD

FIG. 21 is a front view of yawing of an image blur correction device for a lens barrel according to an eighth embodiment.

FIG. 22 is a front view of the pitching of the image blur correction device for the lens barrel according to the eighth embodiment.

[Explanation of symbols]

 Reference Signs List 1 image blur correction lens group 2 pitching moving frame 4 yawing moving frame 6p, 6y shift actuator 9p, 9y yoke 10 fixed frame 12p, 12y light emitting element 14p, 14y light receiving element 15 PSD board 16 flexible print cable for pitching frame 17 yawing Flexible print cable for frame 20 Shift unit 33 Linear actuator 41, 51 Magnetic sensor 47 Stepping motor with encoder

Claims (8)

[Claims] 1. A magnet which is magnetized perpendicularly to a driving direction, a yoke, and has a predetermined gap with the magnet, and is movable in the driving direction by applying a current so as to be orthogonal to a magnetic flux generated by the magnet. A linear actuator constituted by a flexible coil and position detecting means,
A stepping motor, an encoder magnet that is cylindrical or columnar, is multipolarly magnetized in the circumferential direction, and is rotatably mounted coaxially with the stepping motor, and is disposed to face the peripheral edge of the encoder magnet. A stepping motor with an encoder constituted by a magnetic sensor, a first moving lens group driven in the optical axis direction by the linear actuator, and a second moving lens group driven in the optical axis direction by the stepping motor with the encoder. A moving lens group, wherein the magnetic sensor of the stepping motor with the encoder is disposed at a substantially symmetric center position when viewed from a driving direction of a magnetic circuit formed by the magnet and the yoke of the linear actuator. Lens barrel. 2. A first and second lens moving frame which holds an image blur correction lens group and is slidable in first and second directions orthogonal to the optical axis at different heights in the optical axis direction. , The first and second
First and second actuators for driving the lens moving frame of the first and second actuators, and among the first and second actuators, the actuator disposed on the optical axis image plane side is configured such that when viewed from the optical axis direction, A lens barrel, which is disposed so as to overlap a lens moving frame disposed on an axis object side. 3. A first lens group for holding a first lens group for image blur correction and slidable in first and second directions orthogonal to the optical axis at different heights in the optical axis direction. A lens moving frame, first and second actuators for driving the first and second lens moving frames, and a linear actuator for moving the second lens group in the optical axis direction. A lens barrel characterized in that the linear actuator is disposed on the optical axis image plane side of the actuator disposed on the optical axis object side in the second actuator so as to overlap as viewed from the optical axis direction. 4. A first and second lens moving frame which holds a first lens group for image blur correction and is slidable in first and second directions perpendicular to an optical axis; A first and a second actuator for driving the second lens moving frame, a fixed frame for slidably holding the first and second lens moving frames, and a second lens group in the optical axis direction. A stepping motor with an encoder to be moved, wherein the fixed frame has a recess formed in a portion surrounded by the first and second actuators, and the stepping motor with the encoder is disposed in the recess. Lens barrel. 5. A first and second lens moving frame which holds a first lens group for image blur correction and is slidable in first and second directions orthogonal to an optical axis; In order to drive the lens moving frame, the first coil, the first magnet that is magnetized on one side and is arranged to face the first coil, and the first magnet are held. A first actuator having a substantially U-shaped first yoke; a second coil for driving the second lens holding frame; A second magnet having a second magnet disposed to face the second coil, and a substantially U-shaped yoke holding the second magnet; and the first and second lens moving frames. And holds the first and second actuators and is surrounded by the first and second actuators. Lens barrel having an image blur correction device consisting of a fixed frame having a concave portion in the portion,
A stepping motor with an encoder for moving the second lens group in the optical axis direction is provided in the recess of the fixed frame, and the first and second magnets are arranged so that the polarities of the first and second magnets are opposite when viewed from the optical axis center. A lens barrel characterized by being provided. 6. A first and second lens moving frame which holds an image blur correction lens group and is slidable in first and second directions orthogonal to the optical axis at different heights in the optical axis direction. , The first and second
First and second actuators for driving the lens moving frame, and an aperture driving actuator;
A lens barrel, wherein the diaphragm driving actuator is disposed on the optical axis object side of the actuator disposed on the optical axis image plane side of the actuators. 7. A first and second lens moving frame which holds an image blur correction lens group and is slidable in first and second directions orthogonal to the optical axis at different heights in the optical axis direction. , The first and second
A lens barrel having an image blur correction device including first and second actuators for driving the first lens moving frame, wherein the first lens is disposed integrally with the first lens moving frame, A light-emitting portion of the first position detecting means for detecting the position of the moving frame; and a second position detecting means provided integrally with the second lens moving frame and detecting the position of the second lens moving frame. And a substrate on which the light receiving portions of the first and second position detecting means are disposed, and the light emitting portions of the first and second position detecting means have substantially the same height when viewed from the optical axis direction. A lens barrel characterized in that it is disposed at the same time. 8. A first and second lens moving frame which holds an image blur correcting lens group and is slidable in first and second directions orthogonal to an optical axis; A first electrical component which is integrated with the first moving frame driving means and a position detecting means; and a second lens moving frame driving means and a position detecting means which are integrated with the second lens moving frame. A second electric component, a fixing frame for slidably fixing the first and second lens moving frames, and a first flexible printed cable electrically connected to the first electric component. A lens barrel including an image blur correction device including a second flexible printed cable electrically connected to the second electrical component, wherein one end of the first flexible printed cable is connected to the second flexible printed cable. 1 on the opposite side of the optical axis center of the driving means and at the front The second drive means is fixed to the first lens moving frame on the same side, and one end of the second flexible printed cable is opposite to the optical axis center of the first and second drive means. And the other ends of the first and second flexible printed cables are substantially parallel to a sliding direction of the first lens moving frame. A lens barrel fixed to the fixed frame on the opposite side of the optical axis center of the driving means.