JP2009282448A - Blurring correcting device and optical equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a blurring correcting device can correct precisely blurring, and to provide optical equipment. <P>SOLUTION: This blurring correcting device has a moving member 32 movable relatively to fixed members 34, 36; driving members 40a, 40b, 38a, 38b for moving the moving member 32 relatively to the fixed members 34, 36 by electromagnetic force, magnetic sensors 42a, 42b for detecting relative positions of the moving member 32 to the fixed members 34, 36; and a control part 14 for controlling the driving members 40a, 40b to stop the driving of the driving members 40a, 40b, when calibrating the magnetic sensors 42a, 42b. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a shake correction apparatus and an optical apparatus.

  Various types of blur correction apparatuses that can suppress blurring of a captured image due to camera shake or the like are known. For example, as shown in Patent Document 1 below, the correction lens is shifted in both the X axis and the Y axis in accordance with the detected camera shake in the XY plane perpendicular to the optical axis Z. Optical blur correction apparatuses are known.

  In such an optical shake correction apparatus, there is a case where the same magnet is used as a driving magnet and a position detection magnet in order to reduce the size of the apparatus. However, in this case, the distance between the driving coil and the position detecting Hall element becomes short, and a crosstalk signal based on the current of the driving coil is superimposed on the detection signal detected from the Hall element, thereby detecting the position. The accuracy may be reduced.

  If the accuracy of position detection by the Hall element decreases, the accuracy of camera shake correction may decrease. In addition, an error may occur during calibration of the position detection signal by the Hall element. At the time of calibration, the movable part is moved to both ends of the mechanical limit of the drive shaft, and calibration is performed by reading the output of the Hall element at that time.

When reading the output of the Hall element, current flows through the drive coil, so the Hall element superimposes the crosstalk signal from the drive coil on the position detection signal based on the magnetic flux of the drive magnet. Therefore, there is a possibility that calibration cannot be performed accurately. If the calibration cannot be performed accurately, it becomes difficult for the Hall element to detect an accurate position, and the accuracy of camera shake correction deteriorates.
JP 2007-121518 A

  The present invention has been made in view of such a situation, and an object thereof is to provide a shake correction device and an optical apparatus that can realize high-precision shake correction.

In order to achieve the above object, a shake correction apparatus according to the present invention includes:
A movable member (32) movable relative to the fixed members (34, 36);
A drive member (40a, 40b, 38a, 38b) for moving the moving member (32) relative to the fixed member (34, 36) by electromagnetic force;
A magnetic sensor (42a, 42b) for detecting a relative position between the fixed member (34, 36) and the moving member (32);
And a controller (14) for controlling the drive members (40a, 40b) so as to reduce the drive of the drive members (40a, 40b) when the magnetic sensors (42a, 42b) are calibrated.
The controller (14) may control the drive member (32) to stop the drive of the drive member (32) when calibrating the magnetic sensors (42a, 42b).

  In the shake correction apparatus according to the present invention, the drive members (40a, 40b) are calibrated to reduce or stop the drive of the drive members (40a, 40b) and calibrate the output signals of the magnetic sensors (42a, 42b). Crosstalk from 40b) is eliminated, and accurate calibration of the magnetic sensors (42a, 42b) becomes possible. Therefore, highly accurate shake correction control can be realized.

The fixing member (34, 36) includes a restricting member (37) for restricting the movement of the moving member (32),
The controller (14) may calibrate the magnetic sensors (42a, 42b) at a position where the moving member (32) is in contact with the restricting member (37). Since the position where the moving member (32) is in contact with the restricting member (37) is a known position as a reference, the magnetic sensor (42a) is calibrated by calibrating the output signal of the magnetic sensor (42a, 42b) at that position. 42b) can be accurately calibrated.

  The controller (14) moves the moving member (32) along the detection axis of the magnetic sensor (42a, 42b) before the calibration of the magnetic sensor (42a, 42b). You may contact | abut to a member (37). By moving the moving member (32) along the detection axis of the magnetic sensor (42a, 42b) and bringing it into contact with the limiting member (37), the detection signal of the magnetic sensor (42a, 42b) and the moving member (32) ) Can be easily correlated with the movement position, and accurate calibration of the magnetic sensors (42a, 42b) becomes possible.

  Preferably, the direction of the detection axis of the magnetic sensor (42a, 42b) substantially coincides with the direction of the drive axis of the drive unit. By making the direction of the detection axis of the magnetic sensor (42a, 42b) substantially coincide with the direction of the drive axis of the drive unit, the detection signal of the magnetic sensor (42a, 42b) and the movement position of the moving member (32) Correlation is easy to take, and accurate calibration of the magnetic sensors (42a, 42b) becomes possible.

  Preferably, the control unit (14), after the moving member (32) abuts on the restriction member (37), after a predetermined time has elapsed until the output of the magnetic sensor (42a, 42b) is stabilized, The energization to the drive member (40a, 40b) is stopped. By stopping energization, crosstalk can be prevented.

Preferably, the drive member includes a drive coil (40a, 40b) and a drive magnet (38a, 38b) disposed to face the drive coil (40a, 40b),
One of the fixed member (34, 36) and the moving member (32) is provided with the magnetic sensor (42a, 42b) and the drive coil (40a, 40b),
The other of the fixed member (34, 36) and the moving member (32) is provided with the driving magnet (38a, 38b).

  The drive magnets (38a, 38b) used as the drive member and the position detection magnets (38a, 38b) by the magnetic sensors (42a, 42b) are also used as the same magnet, thereby reducing the size of the apparatus. .

  Preferably, the moving member (32) includes an optical system (L3) for correcting image blur. Image blur can be corrected by moving the optical system. Alternatively, the moving member (32) may include an image sensor (3) that captures an image by an optical system.

  An optical apparatus according to the present invention includes the above-described blur correction device (30).

  In the above description, in order to explain the present invention in an easy-to-understand manner, the description has been made in association with the reference numerals of the drawings showing the embodiments, but the present invention is not limited to this. The configuration of the embodiment described later may be improved as appropriate, or at least a part of the configuration may be replaced with another component. Further, the configuration requirements that are not particularly limited with respect to the arrangement are not limited to the arrangement disclosed in the embodiment, and can be arranged at a position where the function can be achieved.

Hereinafter, the present invention will be described based on embodiments shown in the drawings.
FIG. 1 is a schematic view of a camera according to an embodiment of the present invention.
2A is a schematic exploded perspective view of the camera shake correction unit shown in FIG.
2B is a plan view of the movable part shown in FIG. 2A.
2C is a schematic cross-sectional view of the camera shake correction unit shown in FIG. 2A.
2D is an explanatory diagram of the mechanical limit.
FIG. 3 is a flowchart of calibration performed by the CPU shown in FIG.
FIG. 4 is a graph showing an example of calibration.
FIG. 5 is a graph illustrating crosstalk.
6A and 6B are graphs showing that an error has occurred due to crosstalk during calibration,
FIG. 7 is a graph showing an example of successful calibration.

  As shown in FIG. 1, a camera 1 according to an embodiment of the present invention is a so-called compact camera, in which a camera body 1a and a lens barrel 2 are integrated. The lens barrel 2 includes an imaging optical system configured by arranging a first lens group L1, a second lens group L2, and a third lens group (blur correction lens group) L3 in order from the objective side. In the camera 1 of this embodiment, the shutter 4 and the image pickup device 3 such as a CCD are provided behind the third lens unit L3 (on the image plane side).

  The first lens unit L1 is provided on the most object side in the imaging optical system, and is driven to move along the optical axis Z by the drive mechanism 6 so that zooming is possible. The second lens unit L2 is driven to move along the optical axis Z by the drive mechanism 8, and focusing is possible.

  The third lens group (blur correction lens group) L3 constitutes a part of the blur correction apparatus 30. The configuration and function of the shake correction apparatus 30 will be described in detail later. The third lens unit L3 shifts and displaces in the plane perpendicular to the optical axis Z with respect to the other lens units, thereby reducing image blur due to camera movement.

  The shutter 4 and the aperture mechanism (not shown) are driven by the drive mechanism 10 so as to control the exposure of the camera. The imaging element 3 generates an electrical image output signal based on the light of the subject image formed on the imaging surface by the imaging optical system, and the signal is converted by the signal processing circuit 16 into A / D conversion and noise. Processed and input to the CPU 14.

  The lens barrel 2 has a built-in gyro sensor 12 that detects angular velocity such as camera shake generated in the camera 1 and outputs it to the CPU 14. A detection signal from the AF sensor 18 is also output to the CPU 14, and the drive mechanism 8 is controlled based on the detection signal to realize an autofocus mechanism.

  The CPU 14 is connected to a recording medium 20, a nonvolatile memory 22, and various operation buttons 24. The recording medium 20 is a memory that receives an output signal from the CPU 14 and records or reads a photographed image. For example, the recording medium 20 is a detachable card type memory.

  The nonvolatile memory 22 stores adjustment value information such as a gain value of the gyro sensor, and is configured by a semiconductor memory or the like built in the camera together with the CPU 14. Examples of the various operation buttons 24 include a release switch, and the signal is input to the CPU 14 when the release switch is half-pressed or fully pressed.

  Hereinafter, the blur correction device 30 built in the lens barrel 2 of the camera 1 will be described in detail. As shown in FIGS. 2A to 2C, the shake correction device 30 has a first fixing portion 34 fixed to the lens barrel 2 of the camera 1, and the A axis and the B axis with respect to the first fixing portion 34. And a movable portion 32 that is movable in a plane direction including the movable portion 32. As shown in FIG. 2B, a lens holding frame 48 that holds the third lens unit L3 is fixed to the movable portion 32.

  A plane including the A axis and the B axis is a plane perpendicular to the optical axis Z shown in FIG. It is preferable that the A axis and the B axis be perpendicular to each other because the position coordinates of the movable portion 32 are simplified, but they are not necessarily perpendicular.

  2A and 2C, the movable part 32 is sandwiched between the first fixed part 34 and the second fixed part 36 along the optical axis Z direction. Similar to the first fixing portion 34, the second fixing portion 36 is fixed to the lens barrel 2 shown in FIG. As shown in FIG. 2C, a ball bearing 44 is disposed between the first fixed portion 34 and the movable portion 32, and the movable portion 32 has the A axis and the B axis with respect to the first fixed portion 34. It moves smoothly in the plane direction including it.

  In order to keep the movable part 32 in contact with the ball bearing 44 and not rub against the second fixed part 36 when the movable part 32 is moved, as shown in FIG. The part 34 is connected by a plurality of springs 35. These springs 35 also have a function of positioning the center of the third lens unit L3 near the center of the mechanical limit 37 as shown in FIG.

  As shown in FIG. 2A, the mechanical limit 37 is an opening formed at the center of the first fixing portion 34, and a lens holding frame that holds the third lens unit L3 shown in FIG. 2B inside the opening. 48 enters. Therefore, as shown in FIG. 2D, the movement of the third lens unit L3 in the plane direction including the A axis and the B axis is limited by the lens holding frame 48 colliding with the mechanical limit 37. That is, the third lens unit L3 can move within the range of the mechanical limit 37.

  The electromagnetic actuator is movable with respect to the first fixed portion 32 in order to drive and move the movable portion 32 with respect to the first fixed portion 34 and the second fixed portion 36 within an A-axis-B-axis plane orthogonal to the optical axis Z. It is attached to the part 32.

  The electromagnetic actuator has a pair of a first drive magnet 38a and a first drive coil 40a, and a pair of a second drive magnet 38b and a second drive coil 40b. The first drive magnet 38 a and the second drive magnet 38 b are fixed to the movable portion 32, and the first drive coil 40 a and the second drive coil 40 b are attached to the first fixed portion 34. A yoke may be attached to each of the drive magnets 38a and 38b.

  The first drive coil 40a and the second drive coil 40b are driven based on a drive signal from the CPU 14 shown in FIG. 1, and a magnetic field generated in the first drive coil 40a is generated by flowing a predetermined current. Acting on one driving magnet 38a, a driving force for moving the movable portion 32 along the A-axis direction is generated. Similarly, the magnetic field generated in the second driving coil 40b acts on the second driving magnet 38a to generate a driving force that moves the movable portion 32 along the B-axis direction.

  That is, the third lens group L3 fixed to the movable portion 32 is adjusted to a state shown in FIG. 2D by adjusting the current flowing through the first drive coil 40a and the second drive coil 40b based on the drive signal from the CPU 14. Within the range of the mechanical limit 37 shown, it can be freely moved in the A-axis-B-axis plane. The driving force for moving the movable portion 32 is performed by adjusting the current flowing through the first driving coil 40a and the second driving coil 40b. This can be realized, for example, by changing the duty ratio of pulse width modulation (PWM) control.

  The CPU 14 shown in FIG. 1 drives the movable part 32 relative to the first fixed part 34 according to the blur acceleration of the camera 1 detected by an angular velocity sensor such as the gyro sensor 12, for example, and the light of the third lens group L3. Image blurring can be reduced by controlling the movement of the axis center with respect to the optical axis Z of the other lens units L1 and L2.

  Further, in order to detect the movement position of the movable part 32 with respect to the first fixed part 34 and the second fixed part 36 in the A-axis-B-axis plane, the second fixed part 36 includes a first magnet 38a and a first magnet 38a. Corresponding to the two magnets 38b, first and second Hall elements 42a and 42b as position detection sensors are arranged.

  The first Hall element 42a detects a magnetic field that changes in the A-axis direction as the magnet 38a moves in the A-axis direction, and detects the movement position of the movable part 32 in the A-axis direction. Further, the second Hall element 42b detects a moving position of the movable portion 32 in the B-axis direction by detecting a magnetic field that changes in the B-axis direction as the magnet 38b moves in the B-axis direction. In the present embodiment, the position detection axis by these Hall elements 42a and 42b and the drive axis by the electromagnetic actuator are common to the A axis and the B axis, respectively.

  In the present embodiment, the magnets 38 a and 38 b as electromagnetic actuators also serve as part of the position detection sensor of the movable portion 32. That is, the Hall element 42a detects a change in the magnetic field corresponding to the movement position of the magnet 38a in the A-axis direction, and the Hall element 42b detects a change in the magnetic field corresponding to the movement position of the magnet 38b in the B-axis direction. ing.

  As described above, the position of the movable portion 32 is detected by the Hall elements 42a and 42b detecting changes in the magnetic fields of the magnets 38a and 38b and converting the output voltages of the Hall elements 42a and 42b into position information. The conversion from the output voltage to the position information is performed by the CPU 14 shown in FIG.

  However, the magnetic field detected by these Hall elements 42a and 42b also varies depending on the distance between the magnet 38a (or 38b) and the Hall element 42a (or 42b), the ambient temperature, and the like. For this reason, in order to accurately detect the position of the movable portion 32 and to perform accurate blur correction, it is necessary to calibrate the Hall elements 42a and 42b before photographing.

  In the calibration of the Hall element 42a, the lens holding frame 48 of the movable portion 32 shown in FIG. 2B is pressed at both ends of the mechanical limit 37 shown in FIGS. 2A and 2D in the A-axis direction. Then, adjustment is performed so that the output voltage value from the Hall element 42a at that time becomes Vmin or Vmax shown in FIG. That is, the inclination adjustment (γ adjustment) and shift adjustment of the output voltage straight line with respect to the stroke (position) are performed so that the output voltage from the Hall element 42a becomes Vmin or Vmax at the position of the mechanical limit 37 in the A-axis direction. The intermediate voltage Vtyp between Vmin and Vmax in the output voltage of the calibrated Hall element 42a corresponds to the case where the third lens unit L3 is located at the center of the mechanical limit 37.

  Similarly, in the calibration of the Hall element 42b, the lens holding frame 48 of the movable portion 32 shown in FIG. 2B is pushed to both ends in the B-axis direction of the mechanical limit 37 shown in FIGS. 2 (A) and 2 (D). At the applied position, adjustment is performed so that the output voltage value from the Hall element 42a at that time becomes Vmin or Vmax shown in FIG.

  However, the output voltage of the Hall elements 42a and 42b is affected by the coil current flowing through the driving coil 40a or 40b shown in FIG. 2A. As shown in FIG. Error signals for crosstalk due to current are mixed. That is, originally, the output voltage of the Hall element corresponding to the moving position of the movable portion 32 is Vh + ′ shown in FIG. 5, but becomes Vh + due to the influence of the crosstalk caused by the coil current.

  Conventionally, even when the Hall elements 42a and 42b are calibrated, as shown in FIG. 6A, the output voltage of the Hall element on which the error ΔV for the crosstalk is superimposed may be γ adjusted or shifted. Therefore, the position detection accuracy of the movable portion 32 is lowered, the accuracy of camera shake correction is deteriorated, and there is a possibility that an error of ΔLmax occurs at the maximum as shown in FIG. 6B.

  In the embodiment of the present invention, the following configuration improves the accuracy of calibration of the Hall elements 42a and 42b, improves the position detection accuracy of the movable portion 32, and as a result, improves the accuracy of camera shake correction. Yes. In other words, in the present embodiment, the CPU 14 shown in FIG. 1 calibrates the Hall elements 42a and 42b shown in the flowchart shown in FIG. 3, thereby improving the position detection accuracy of the movable part 32 and, as a result, the camera shake correction. The accuracy is improved.

  As shown in step S1 shown in FIG. 3, when a calibration signal is input to the CPU 14 shown in FIG. 1, first the calibration (mechanism centering process) of the hall element 42a that detects the movement of the movable part 32 in the A-axis direction. )I do. The condition for inputting the calibration signal to the CPU 14 shown in FIG. 1 is not particularly limited, but it can be considered every time when the power of the camera 1 is turned on.

  Next, in step S2, the driving coil 40a shown in FIG. 2A is driven, and as shown in FIG. 2D, the lens holding frame 48 in the movable portion 32 is moved to the mechanical limit 37a + in the A-axis direction. In order to drive the drive coil 40a, a pulsed coil voltage having a predetermined duty ratio may be applied to the drive coil 40a as shown in FIG.

  The duty ratio in FIG. 7 is the ratio of f2 / f1 when the drive period of the coil voltage in pulse modulation control (PWM) is f1, f2 is the voltage ON time, and f3 is the voltage OFF time. It is. When the duty ratio is close to 1, the driving force is maximized, and when it is close to 0, the driving force is weak.

  Whether or not the lens holding frame 48 shown in FIG. 2D hits the mechanical limit 37a + in the A-axis direction may be detected by a position sensor or the like, but the pulsed coil voltage is shown in FIG. 2A for a predetermined time or more. It may be continuously applied to the driving coil 40a. This is because if the pulsed coil voltage is continuously applied to the driving coil 40a shown in FIG. 2A for a predetermined time or longer, the lens holding frame 48 shown in FIG. 2D will always hit the mechanical limit 37a + in the A-axis direction. The predetermined time in that case is obtained in advance by experiments and stored in the nonvolatile memory 22 shown in FIG.

  Next, in step S3, the CPU 14 shown in FIG. 1 stops energization of the drive coil 40a shown in FIG. 2A. Thereafter, in step S4, the CPU 14 shown in FIG. 1 measures a predetermined time and waits until the output of the Hall element 42a is stabilized as shown in FIG. The predetermined time in this case is a time longer than the falling time of the current (coil current) flowing through the driving coil 40a as shown in FIG.

  Next, in step S5, the CPU 14 shown in FIG. 1 reads the output voltage Vh + of the Hall element 42a shown in FIG. 2A. The output voltage Vh + is based on the magnetic field generated from the magnet 38a shown in FIGS. 2A and 2B at the position where the lens holding frame 48 shown in FIG. 2D hits the mechanical limit 37a + in the A-axis direction. It corresponds exactly to the mechanical limit 37a + position in the A-axis direction. The output voltage Vh + does not include a crosstalk signal due to the coil current.

  Next, in step S6, the driving coil 40a shown in FIG. 2A is driven, and as shown in FIG. 2D, the lens holding frame 48 in the movable portion 32 is moved in the reverse direction to the mechanical limit 37a- in the A axis direction. The driving method of the driving coil 40a is the same as in step S2, but a stepped coil voltage in the reverse direction may be applied to the driving coil 40a.

  Next, in step S7, the CPU 14 shown in FIG. 1 stops energization of the drive coil 40a shown in FIG. 2A. Thereafter, in step S8, in the same manner as in step S4, the process waits until the output of the hall element 42a is stabilized.

  Next, in step S9, as in step S5, the CPU 14 shown in FIG. 1 reads the output voltage Vh− of the Hall element 42a shown in FIG. 2A. The output voltage Vh− is based on the magnetic field generated by the magnet 38a shown in FIGS. 2A and 2B at the position where the lens holding frame 48 shown in FIG. 2D hits the mechanical limit 37a− in the A-axis direction. Corresponds precisely to the mechanical limit 37a-position of the part 32 in the A-axis direction. The output voltage Vh− does not include a crosstalk signal due to the coil current.

  Next, in step S10, the Hall element 42a is calibrated based on the output voltages Vh + and Vh− of the Hall element 42a thus obtained. As described above, at the positions of the mechanical limit 37a + and the mechanical limit 37a- in the A axis direction, as shown in FIG. 4, the output with respect to the stroke (position) is such that the output voltage from the Hall element 42a becomes Vmin or Vmax. Adjusts the slope of the voltage line (γ adjustment) and shift adjustment. The intermediate voltage Vtyp between Vmin and Vmax at the output voltage of the calibrated Hall element 42a corresponds to the case where the third lens unit L3 is positioned at the center of the mechanical limit 37a + and the mechanical limit 37a− in the A-axis direction.

  Next, in step S11, a mechanical centering process is performed on the B axis that intersects the A axis. The mechanical centering process on the B-axis is performed by replacing the Hall element 42a with the Hall element 42b, replacing the coil 40a with the coil 40b, replacing the magnet 38a with the magnet 38b, replacing the mechanical limit 37a + with the mechanical limit 37b +, and mechanical limit 37a. -Is replaced with the mechanical limit 37b-, and the same processing as in steps S2 to S10 in the A-axis is performed. Thereafter, in step S12, the entire calibration control is terminated.

  In the shake correction apparatus according to the present embodiment, the supply of the drive voltage to the coils 40a and 40b is stopped, and the output voltages of the hall elements 42a and 42b are calibrated. Therefore, the crosstalk signal due to the coil current flowing through the driving coils 40a and 40b is not superimposed, and the Hall elements 42a and 42b can be accurately calibrated. Therefore, highly accurate shake correction control can be realized.

  In the present embodiment, the shake correction device 30 can be reduced in size by combining the driving magnets 38a and 38b and the position detecting magnets 38a and 38b by the Hall elements 42a and 42b with the same magnet.

  The present invention is not limited to the above-described embodiment, and can be variously modified. For example, the fixed parts 34 and 36 and the movable part 32 may be reversed. That is, the driving magnets 38 a and 38 b may be attached to the fixed portion 34 or 36, and the coils 40 a and 40 b and the hall elements 42 a and 42 b may be attached to the movable portion 32. However, in view of the ease of wiring and the like, the embodiment shown in the above-described drawings is preferable.

  Furthermore, the blur correction device can be applied not only to the lens driving method but also to the CCD driving method. That is, instead of moving the correction lens unit L3 in a plane perpendicular to the optical axis Z, the type of blur correction is such that the image pickup device 3 such as a CCD is moved in a plane perpendicular to the optical axis Z in accordance with camera shake. It can also be applied to devices.

  In addition, the blur correction device according to the present embodiment can be applied not only to the camera 1 having the lens barrel 2 but also to other optical devices such as the lens barrel itself, a still camera, a video camera, a telescope, and a microscope. .

  The calibration may be performed only once when the camera 1 is shipped, but it is preferable to perform the calibration every time the camera 1 is turned on. This is because the output signal of the Hall element and the actual lens position may be deviated due to changes over time.

  In the above-described embodiment, the detection axes of the Hall elements 42a and 42b and the drive axes of the drive coils 40a and 40b are coincident with each other. However, since calculation such as coordinate conversion is not required, it is preferable that the detection axes of the Hall elements 42a and 42b coincide with the drive axes of the drive coils 40a and 40b.

FIG. 1 is a schematic view of a camera according to an embodiment of the present invention. 2A is a schematic exploded perspective view of the camera shake correction unit shown in FIG. FIG. 2B is a plan view of the movable part shown in FIG. 2A. 2C is a schematic cross-sectional view of the camera shake correction unit shown in FIG. 2A. FIG. 2D is an explanatory diagram of a mechanical limit. FIG. 3 is a flowchart of calibration performed by the CPU shown in FIG. FIG. 4 is a graph showing an example of calibration. FIG. 5 is a graph illustrating crosstalk. FIG. 6A is a graph showing that an error has occurred due to crosstalk during calibration. FIG. 6B is a graph showing that an error has occurred due to crosstalk during calibration. FIG. 7 is a graph showing an example of successful calibration.

Explanation of symbols

1 ... Camera 2 ... Lens barrel 14 ... CPU
30 ... Shake correction device 32 ... Movable parts 34, 36 ... Fixed part 37 ... Mechanical limits 38a, 38b ... Driving magnets 40a, 40b ... Driving coils 42a, 42b ... Hall elements

Claims (10)

A movable member movable relative to the fixed member;
A drive member that moves the moving member relative to the fixed member by electromagnetic force;
A magnetic sensor for detecting a relative position between the fixed member and the moving member;
And a controller that controls the drive member to reduce the drive of the drive member when the magnetic sensor is calibrated.   The shake correction apparatus according to claim 1, wherein the controller controls the drive member to stop driving the drive member when the magnetic sensor is calibrated. The fixing member includes a restricting member that restricts movement of the moving member,
The shake correction apparatus according to claim 1, wherein the control unit calibrates the magnetic sensor at a position where the moving member is in contact with the limiting member.   The shake correction apparatus according to claim 3, wherein the control unit moves the moving member along a detection axis of the magnetic sensor and abuts the limiting member before calibrating the magnetic sensor.   The shake correction apparatus according to claim 4, wherein the direction of the detection axis of the magnetic sensor substantially coincides with the direction of the drive axis of the drive unit.   6. The control unit according to claim 4, wherein the control unit stops energization of the drive unit after a predetermined time elapses until the output of the magnetic sensor is stabilized after the moving member contacts the limiting member. Blur correction device. The drive member has a drive coil and a drive magnet arranged to face the drive coil;
One of the fixed member and the moving member is provided with the magnetic sensor and a driving coil,
The blur correction device according to claim 1, wherein the driving magnet is provided on the other of the fixed member and the moving member.   The blur correction apparatus according to claim 1, wherein the moving member includes an optical system for correcting image blur.   The blur correction apparatus according to claim 1, wherein the moving member includes an image sensor that captures an image by an optical system.   An optical apparatus including the shake correction apparatus according to claim 1.

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