JP2010286810A - Blur correction device and optical instrument - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a blur correction device and an optical instrument allowing suitable photographing. <P>SOLUTION: The blur correction device includes an optical component 203b to correct an image blur, a second member 6 capable of vibrating relatively to a first member 7, and elastic members 503, 5031 and 5032 arranged between the first member 7 and the second member 6 and pressed to the first member 7 and the second member 6 to be deformed in the direction crossing the direction of the relative vibration between the first member 7 and the second member 6. The elastic members 503, 5031 and 5032 attenuate the relative vibration between the first member 7 and the second member 6. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

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

  In a camera equipped with a shake correction system, for example, a mechanism for holding a shake correction lens in the center by biasing the shake correction lens in a direction orthogonal to the optical axis using a plurality of coil springs is known. However, in this mechanism, when some disturbance accompanying the photographing operation is applied, the blur correction lens resonates, and it takes time to attenuate the vibration.

  In addition, a technique for attenuating unnecessary vibrations of a shake correction lens using a damper mechanism is known (see Patent Document 1).

  However, such a mechanism causes an increase in the size of the shake correction system and increases power consumption. In addition, a manufacturing error occurs in the plurality of coil springs, and when the blur correction lens is shifted in a direction orthogonal to the optical axis during the blur correction operation, there is a possibility that an error occurs in the restoring force depending on the shift direction.

JP 2008-286929 A

  The present invention has been made in view of such a situation, and an object of the present invention is to provide a shake correction apparatus and an optical apparatus that can perform suitable shooting.

In order to achieve the above object, a shake correction apparatus (400) according to the present invention includes:
A second member (6) provided with an optical component (203b) for correcting image blur and capable of relatively vibrating with respect to the first member (7);
Provided between the first member (7) and the second member (6) in a direction intersecting the direction of relative vibration between the first member (7) and the second member (6). Elastic members (503, 5031, 5032) pressed against the first member (7) and the second member (6) and deformed,
The elastic members (503, 5031, 5032) are characterized by attenuating relative vibration between the first member (7) and the second member (6).

  The elastic members (503, 5031, 5032) are arranged to be pressed against the first member (7) and the second member (6), thereby effectively attenuating unnecessary vibration of the second member (6). The centering at the time of non-energization becomes possible with a simple configuration. Further, since the elastic members (503, 5031, 5032) have an elastic force and press the second member (6) in a direction parallel to the optical axis, the second member (6) is moved to the first member. Positioning in the optical axis direction is possible with respect to (7). In addition, the vibration of the second member (6) in the direction orthogonal to the optical axis can be attenuated when not energized, and the second member (6) can be shifted with a light force during the anti-vibration operation. (400) can contribute to miniaturization and power saving.

  The elastic member (503, 5031, 5032) may include a non-metallic material. The elastic members (503, 5031, 5032) may include a polymer material. The elastic members (503, 5031, 5032) have an elastic force, and may press the second member (6) in a direction parallel to the optical axis.

  When the second member (6) is in the first range (L1) and when the second member (6) is in the second range (L2) outside the first range (L1), It has a control part (1500) which can control relative vibration of the 1st member (7) and the 2nd member (6), and the elastic members (503, 5031, 5032) are the 2nd member When the (6) is in the first range (L1), the elastic member (503, 5031, 5032) is deformed more than when the second member (6) is in the second range (L2). The linearity of the relationship between the amount (x) and the pull back force (F) caused by the deformation of the elastic members (503, 5031, 5032) may be high.

  When the second member (6) is in the first range (L1), the control unit (1500) performs control with higher accuracy than when the second member (6) is in the second range (L2). When the second member (6) is in the second range (L2), the second member (6) may be pulled back into the first range (L1).

  When the second member (6) is in the first range (L1), there is a relationship between the amount of deformation of the elastic members (503, 5031, 5032) and the pullback force due to the deformation of the elastic members (503, 5031, 5032). Since the linearity is high, the second member (6) can be controlled with high accuracy. Further, when the second member (6) is in the second range (L2) outside the first range (L1), more power-saving control is possible.

  You may have a restriction | limiting part (ML, 71) with which the movement of the said 2nd member (6) was provided outside the said 2nd range (L2).

  The elastic members (503, 5031, 5032) have the first member (7) and the second member (632) as seen in a cross section in the direction of relative vibration between the first member (7) and the second member (6). The cross-sectional area (S1) when pressed and deformed by the two members (6) is from the cross-sectional area (S0) before being pressed and deformed by the first member (7) and the second member (6). May be large. The elastic member (503, 5031, 5032) swells at the center side of the end portion when viewed in a direction intersecting the direction of relative vibration between the first member (7) and the second member (6). It may be a shape.

  It has a guide member (502, 502p, 502q, 502r) for guiding relative vibration between the first member (7) and the second member (6), and the first member (7) It has a first surface (403a) with which the members (503, 5031, 5032) come in contact and a second surface (7a) opposite to the first surface, and the second member (6) is made of the elastic member ( 503, 5031, 5032) and a fourth surface (6b) provided on the opposite side of the third surface, the guide member (502, 502p, 502q, 502r). ) May be provided in contact with the second surface (7a) and the fourth surface (6b).

  By providing the guide member (502, 502p, 502q, 502r), the optical component (203b) can be guided so as to move smoothly in a direction orthogonal to the optical axis direction.

  The elastic members (503, 5031, 5032) may be integrated with the coil spring (505). This facilitates the inclination of the straight line of the relationship between the deformation amount (x) of the elastic member (503, 5031, 5032) and the pull back force (F) resulting from the deformation of the elastic member (503, 5031, 5032). The design can be changed, and the design can be easily changed according to the type and purpose of the blur correction.

  The plurality of elastic members (503, 5031, 5032) are plural, and each of the plurality of elastic members (503, 5031, 5032) includes the center of gravity of the second member (6) and the optical component (203b). It may be provided at a position approximately equidistant from at least one of the optical axes.

  By adopting such a configuration, unnecessary driving around the center of gravity of the second member (6) or the optical axis of the optical component (203b) when the drive unit (40, 41, 40t, 40u, 40v) is driven. Generation of moment can be prevented. Therefore, it is not necessary to separately provide a guide for preventing rotation of the second member (6) around the optical axis, and good drive control performance can be exhibited.

  A drive unit (40, 41, 40t, 40u, 40v) that generates a drive force in the drive force generation direction to relatively vibrate the first member (7) and the second member (6); There are a plurality of elastic members (503, 5031, 5032), and each of the plurality of elastic members (503, 5031, 5032) is in the direction intersecting with the driving force generation direction in the drive unit (40, 41). , 40t, 40u, 40v) may be provided at substantially equidistant positions. That is, the blur correction device (400) includes a plurality of the elastic members (503, 5031, 5032) and a drive unit (40, 41, 40t, 40u, 40v) for driving the second member (6). The elastic members (503, 5031, 5032) are arranged along the direction perpendicular to the driving force generation direction of the driving units (40, 41, 40t, 40u, 40v). 40u, 40v) may be arranged equidistant from the center. A plurality of the guide members (502, 502p, 502q, 502r) are arranged on the first member (7), and an inner side of a circle connecting the centers of the guide members (502, 502p, 502q, 502r). Further, the center of the elastic member (503, 5031, 5032) may be disposed. The center of the elastic member (503, 5031, 5032) is a circle passing through the three guide members (502, 502p, 502q, 502r) selected from the plurality of guide members (502, 502p, 502q, 502r). It may be provided inside.

  By arranging the center of the elastic member (503, 5031, 5032) inside the circle connecting the centers of the guide members (502, 502p, 502q, 502r), the drive unit (40, 41, 40t, 40u, 40v) It is possible to prevent an unnecessary moment from being generated when the is driven.

  The plurality of elastic members (503, 5031, 5032) are plural, and each of the plurality of elastic members (503, 5031, 5032) includes the center of gravity of the second member (6) and the optical component (203b). The rotation angles about at least one of the optical axes may be provided at substantially equal positions. The same number of the elastic members (503, 5031, 5032) as the drive control shafts of the drive units (40, 41, 40t, 40u, 40v) may be arranged at equal intervals along the circumferential direction. In order to relatively vibrate the first member (7) and the second member (6), there are a plurality of drive portions (40, 41, 40t, 40u, 40v) that generate a drive force in the drive force generation direction. The driving force generation directions of the plurality of driving units (40, 41, 40t, 40u, 40v) are at least the center of gravity of the second member (6) and the optical axis of the optical component (203b). A rotation angle around one of the plurality of elastic members (503, 5031, 5032) may be substantially equal to the rotation angle.

  By arranging the elastic members (503, 5031, 5032) in this way, the second member (6) can be stably provided regardless of the number of drive control axes of the drive units (40, 41, 40t, 40u, 40v). Drive control is possible.

  The distance from the center of gravity of the second member (6) and at least one of the optical axes of the optical component (203b) to the elastic member (503, 5031, 5032) is the center of gravity of the second member (6), The distance from at least one of the optical axes of the optical component (203b) to the guide member (502, 502p, 502q, 502r) may be shorter.

  A detector (20, 21) for detecting relative vibration between the first member (7) and the second member (6); a center of gravity of the second member (6); and the optical component. The distance from at least one of the optical axes of (203b) to the center of the elastic member (503, 5031, 5032) is at least the center of gravity of the second member (6) and the optical axis of the optical component (203b). The distance from one side to the detection unit (20, 21) may be shorter.

  An optical apparatus according to the present invention includes the shake correction device (400).

  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.

FIG. 1 is a cross-sectional view of a camera according to an embodiment of the present invention. FIG. 2 is a block diagram showing a shake correction calculation of the camera shown in FIG. FIG. 3 is a side view showing the movable range of the movable member of the camera shake correcting apparatus shown in FIG. 1 as viewed from the Z-axis direction. FIG. 4 is a plan view of the camera shake correction apparatus shown in FIG. 5 is a cross-sectional view taken along the line VV in FIG. 6 is a cross-sectional view taken along the line VI-VI in FIG. FIG. 7 is a schematic cross-sectional view of the shake correction apparatus shown in FIG. 8A is a side view of the rubber bush before being attached to the shake correction apparatus shown in FIG. 4, and FIG. 8B is a side view of the rubber bush after being attached. 9A is a partial cross-sectional view when the shake correction apparatus shown in FIG. 4 is not energized, and FIG. 9B is a partial cross-sectional view when the shake correction apparatus shown in FIG. 4 is in operation. FIG. 10 is a graph showing the relationship between the amount of deformation of the rubber bush attached to the shake correction apparatus shown in FIG. 4 and the force with which the rubber bush is pulled back to the center. FIG. 11 is an explanatory view of a rubber bush according to another embodiment of the present invention. FIG. 12 is a graph showing the relationship between the amount of deformation of the rubber bush according to another embodiment of the present invention and the force with which the rubber bush is pulled back to the center. FIG. 13 is a schematic diagram of a shake correction apparatus that shows the force acting on the movable part during vibration-proof driving. FIG. 14 is a schematic diagram showing the arrangement of rubber bushes and steel balls in a shake correction apparatus according to another embodiment of the present invention. 15 is a schematic cross-sectional view of FIG. 14 showing the force acting on the movable part. FIG. 16 is a schematic diagram showing the arrangement of each member of a shake correction apparatus according to another embodiment of the present invention.

First Embodiment As shown in FIG. 1, a lens barrel 2 is detachably attached to a camera body 1 of a single-lens reflex camera 100 having a shake correction apparatus according to an embodiment of the present invention. In some compact cameras and the like, there is a camera in which the lens barrel 2 and the camera body 1 are integrated, and the type of camera is not particularly limited. In the following description, a single-lens reflex camera in which the lens barrel 2 and the camera body 1 are detachable will be described for ease of explanation.

  The image sensor 101 built in the camera body 1 is composed of, for example, a CCD or a CMOS. A quick return mirror 110, a third lens group 203, a diaphragm 205, a second lens group 202, and a first lens group 201 are arranged in this order on the subject side in the optical axis Z direction from the image sensor 101.

  The lens barrel 2 includes a first lens group 201, a second lens group 202, and a third lens group 203 that can be moved in the Z-axis direction by a cam mechanism (not shown). The focus adjustment lens 201a constituting the first lens group 201 is moved in the Z-axis direction to adjust the focus.

  The shake correction lens 203b constituting the second lens group 203 is supported by the correction lens holding frame 6, and is driven in the X-axis and Y-axis directions to perform shake correction. The Z axis is an optical axis, and the Y axis is a direction perpendicular to the Z axis and the bottom surface 10 of the camera body 1. The X axis is a direction perpendicular to the Z axis and the Y axis. The X axis, the Y axis, and the Z axis are perpendicular to each other. An angular velocity sensor 5 that detects information regarding the velocity of vibration applied to the single-lens reflex camera 100 is disposed below the Y axis of the shake correction lens 203b.

  The lens barrel 2 has an electric circuit board on which an arithmetic unit 1500 (shown in FIG. 2) that performs output signal processing of the angular velocity sensor 5, communication with the camera 1, and the like, a motor driver that drives an actuator that will be described later, and the like are mounted. 214 is attached. The angular velocity sensor 5 is electrically coupled to the electric circuit board 214 by a flexible printed circuit board (FPC) (not shown), and an output signal of the angular velocity sensor 5 is output from LPF, A / A mounted on the electric circuit board 214. The data is input to the arithmetic unit 1500 via the D converter.

  The camera 1 has an optical viewfinder unit for directly observing a subject image formed by the above-described photographing optical system. The optical finder unit includes a quick return mirror 110, a finder screen 111, a pentaprism 112, and an eyepiece lens 113. The quick return mirror 110 is in the position of the solid line in FIG. 1 when waiting for photographing, and the light beam that has passed through the photographing optical system is reflected by the quick return mirror 110 and passes through the finder screen 111, the pentaprism 112, and the eyepiece lens 113. . The user can observe the subject image reflected by the quick return mirror 110 by looking into the eyepiece lens 113.

  At the time of photographing, the quick return mirror 110 moves to the position of the broken line shown in FIG. 1, so that the light beam that has passed through the photographing optical system is imaged on the image sensor 101 and can be photographed.

  Based on FIG. 2, the shake correction apparatus of the present embodiment will be described. When vibration is applied to the camera body 1 shown in FIG. 1, a detection signal is output from the angular velocity sensor 5 shown in FIG. The output value from the angular velocity sensor 5 is amplified to a desired signal level by an amplifier 1501 composed of an amplifier circuit and a low-pass filter, and high frequency noise unnecessary for blur correction is removed.

  The signal output from the amplifier 1501 includes a DC component and low-frequency noise that is not related to image blur correction, that is, a drift signal. For this reason, for example, when a large vibration is input, the dynamic range of the A / D converter 1503 is likely to be exceeded, and the digital signal may not be converted.

  Therefore, before the output value from the amplifier 1501 is input to the A / D converter 1503, the DC signal from the addition output calculation unit 1507 is added. The output value of the addition output calculation means 1507 is converted into an analog signal by the D / A converter 1504. This ensures a vibration amplitude that provides a good S / N ratio, and does not exceed the dynamic range of the A / D converter 1503.

  The output signal of the D / A converter 1504 becomes a DC signal and is input to the adder 1505. Then, the added value is input to the A / D converter 1503. The added value is converted into a digital signal by the A / D converter 1503 and input to the arithmetic unit (MPU) 1500.

  Next, the LPF 1506 removes the direct current component and the low frequency component of the output value of the A / D converter 1503. Thereby, an angular velocity signal that can be integrated can be obtained.

  This angular velocity signal is input to the image blur target position calculation means 701 shown in FIG. The image blur target position calculation unit 701 calculates a correction lens target position signal based on the input angular velocity signal.

  Next, a servo mechanism that drives and controls the shake correction lens 203b shown in FIG. 1 will be described. The corrected lens target position signal output from the image blur target position calculation unit 701 illustrated in FIG. 2 is input to the controller 1702. The controller 1702 is preferably a PID controller, but is not limited to this as long as good controllability can be obtained.

  An output value from the controller 1702 is input to the motor driver 1703, and the motor driver 1703 outputs a driving voltage and a driving current for driving the actuators (VCM) 40 and 41. The motor driver 1703 preferably performs PWM driving for the actuators 40 and 41, but is not limited thereto. The actuators 40 and 41 output a driving force for driving the correction lens driving mechanism 704 including the blur correction lens 203b shown in FIG.

  The correction lens 203b generally corrects the driving force for blur correction at a certain magnification (correction lens image plane movement magnification) when the image movement amount is not equal to the movement amount of the lens itself. The magnification often changes depending on the focal length of the photographing optical system and the subject distance. Therefore, with respect to the obtained change signal of the tilt angle, from the focal length of the photographing optical system constituted by the first lens group 201 to the third lens group 203 shown in FIG. 1, the subject distance, and the correction lens moving magnification, It is necessary to calculate the amount of movement of the correction lens 203b. Therefore, the output signal of the correction lens driving mechanism 704 shown in FIG. 2 is input to the amplifier 705 to calculate the movement amount of the blur correction lens 203b.

  The position of the blur correction lens 203b shown in FIG. 1 is detected by the correction lens position detection sensors 20 and 21 shown in FIG. 2 including a hall element (not shown). Since the output signal from the Hall element is an analog signal, the output signal is converted into a digital signal by the second A / D converter 1705 and then input to the arithmetic unit 1500, and feedback control of the blur correction lens 203b is performed. Done.

  As shown in FIG. 3, the base member 7 has a mechanical limit ML that defines a range in which the correction lens holding frame 6 is physically movable in the direction substantially perpendicular to the optical axis (along the XY plane). Have An annular opening formed at the center of a base member 7 that is a main component of an image blur correction mechanism 400 described later is a mechanical limit ML, and a correction lens holding that holds a shake correction lens 203b inside the opening. The frame 6 enters. Therefore, the movement of the shake correction lens 203b in the plane direction including the X axis and the Y axis is limited by the correction lens holding frame 6 colliding with the mechanical limit ML. That is, the shake correction lens 203b can move within the range of the mechanical limit ML.

  As shown in FIG. 3, in the first range L1 located inside the soft limit SL, the correction lens holding frame 6 is driven by normal blur correction control. In the second range L2 located outside the soft limit SL and inside the mechanical limit ML, a software restriction is applied to the blur correction control in the first range L1. That is, when the VCMs 40 and 41 shown in FIG. 2 are driven, before the correction lens holding frame 6 shown in FIG. 3 reaches the mechanical limit ML (a limiter 71 described later), the image blur correction target position signal described above is obtained. On the other hand, the arithmetic unit 1500 performs some correction. By performing the correction, the correction lens holding frame 6 is prevented from colliding with the mechanical limit ML in the second range L2. Such a boundary between the first range L1 and the second range L2 is the soft limit SL.

  A main configuration of the image blur correction mechanism 400 according to the present embodiment will be described in detail with reference to FIGS. As shown in FIGS. 4 and 5, the image blur correction mechanism 400 is a correction that detects the positions of the VCMs 40 and 41, which are actuators that generate a driving force for driving the blur correction lens 203b, and the image blur correction lens 203b. Lens position detection sensors 20 and 21.

  First, an actuator that generates a driving force for driving the blur correction lens 203b will be described. As shown in FIG. 5, the blur correction lens 203 b is fixed to the correction lens holding frame 6. As shown in FIG. 4, the correction lens holding frame 6 is driven along the XY plane direction by a VCM (Voice Coil Motor) 40 in the Y-axis direction and a VCM 41 in the X-axis direction. VCMs 40 and 41 are electromagnetic actuators. Here, based on the VV cross-sectional view of FIG. 4 shown in FIG. 5, only the VCM 40 in the Y-axis direction will be described as a representative, but the VCM 41 in the X-axis direction has the same configuration only by replacing the Y-axis with the X-axis. Have

  As shown in FIG. 5, the VCM 40 includes a coil 401, a permanent magnet 402, an upper yoke 403, and a lower yoke 404. The permanent magnet 402 is an in-plane two-pole magnetized magnet having two poles polarized to the N and S poles. The permanent magnet 402 is fixed to the lower yoke 404.

  As shown in FIG. 5, the coil 401 is fixed to the correction lens holding frame 6. The lower yoke 404 is fixed to the base member 7. The coil 401 is disposed between the upper yoke 403 and the permanent magnet 402. The permanent magnet 402, the upper yoke 403, and the lower yoke 404 constitute a magnetic circuit in which the magnetic flux loop makes a round.

  Here, in the VCM 40 arranged as described above, when a current is passed through the coil 401 in the magnetic circuit, the coil 401 receives a Lorentz force and drives the shake correction lens 203b in the Y-axis direction. The base member 7 has a limiting portion 71 (the above-described mechanical limit ML), and the correction lens holding frame 6 that supports the shake correction lens 203b is a gap between the correction lens holding frame 6 and the base member 7 shown in FIG. It is movable within the range of X ′.

  Next, the correction lens position detection sensor 20 for detecting the position of the blur correction lens 203b on the XY plane will be described. The position of the shake correction lens 203b is detected by the correction lens position detection sensor 20 in the Y-axis direction and the correction lens position detection sensor 21 in the X-axis direction. Here, based on the VV cross-sectional view of FIG. 4 shown in FIG. 5, only the correction lens position detection sensor 20 in the Y-axis direction will be representatively described.

  As shown in FIG. 5, the correction lens position detection sensor 20 includes a permanent magnet 210, a back yoke 204, and a hall element 203. The permanent magnet 210 and the back yoke 204 are fixed to the correction lens holding frame 6. The hall element 203 is fixed to the electric substrate 2001, and the electric substrate 2001 is fixed to the base member 7. The Hall element is a sensor that outputs a voltage fluctuation amount corresponding to a change in magnetic flux density passing through the element. The permanent magnet 210 and the back yoke 204 are disposed on the correction lens holding frame 6 side, and the Hall element 203 is disposed on the base member 7 side.

  In the correction lens position detection sensor 20, a magnetic circuit is formed in the space on the surface of the permanent magnet 210 by the magnetic circuit formed by the permanent magnet 210 and the back yoke 204, and shows a specific magnetic flux density distribution. Since the shake correction lens 203b, the correction lens holding frame 6, the permanent magnet 210, and the back yoke 204 are integrated, the magnetic flux density that passes through the Hall element 203 when the correction lens holding frame 6 is displaced by the driving force of the VCM 40. Changes, and the output voltage of the Hall element fluctuates.

  Since the relationship of the variation amount of the output voltage in the Hall element 203 with respect to the displacement amount of the correction lens holding frame 6 is known in advance, the position of the correction lens 3 in the Y-axis direction is detected by the variation amount of the output voltage of the Hall element 203. can do. Therefore, by using the correction lens position detection sensor 21 in the X-axis direction shown in FIG. 4 and the correction lens position detection sensor 20 in the Y-axis direction, the position in the XY plane where the vibration correction lens 203b is located is determined. Can be detected.

  Next, the guide mechanism of the blur correction lens 203b will be described based on the VI-VI cross-sectional view of FIG. 4 shown in FIG. The guide mechanism includes a base member 7, a steel ball 502, a rubber bush 503, and a correction lens holding frame 6. FIG. 7 schematically shows the guide mechanism, and the operation thereof will be described later.

  As shown in FIG. 6, the steel ball 502 is housed inside a recess 702 provided in the base member 7. A steel ball sliding surface 602 is provided on the correction lens holding frame 6. The steel ball sliding surface 602 of the correction lens holding frame 6 faces the base member 7 through the steel ball 502. That is, the steel ball 502 is sandwiched between the base member 7 and the steel ball sliding surface 602. Such guide mechanisms 50 are provided at three positions in the image blur correcting mechanism 400 as shown in FIG.

  The correction lens holding frame 6 and the upper yoke 403 are provided with fitting holes 603 and 405, respectively. The rubber bush 503 is provided with projections 503 a and 503 b at both ends in the Z-axis direction. The projection 503 a is fitted in a fitting hole 603 formed in the correction lens holding frame 6, and the projection 503 b is formed on the upper yoke 403. The rubber bush is fitted into the fitting hole 405. The rubber bush 503 is sandwiched between the correction lens holding frame 6 and the upper yoke 403 and is in a state of being compressed and elastically deformed as will be described later, and the direction in which the correction lens holding frame 6 is pressed against the base member 7 along the optical axis Z. Is pressed. Such rubber bushings 503 are arranged at two or more places in the circumferential direction as shown in FIG. 4, and in this embodiment, they are arranged at two positions at 180 degree symmetry.

  As shown in FIG. 4, the rubber bushings 503 and 503 are preferably arranged at an equal distance from the optical axis. That is, the relationship between the radial distances R1 and R2 from the optical axis of the rubber bushes 503 and 503 is preferably R1≈R2. Furthermore, as shown in FIG. 4, the center of the cross section of the rubber bush 503 is preferably arranged inside a circle connecting three steel balls 502 arranged at equal intervals in the circumferential direction. As a result, the guide mechanism guides the shake correction lens 203b so as to be stably and smoothly movable in the direction along the XY plane.

  As shown in the schematic diagram of FIG. 7, the steel ball 502 is moved when the correction lens holding frame 6 is moved along the XY plane by the VCMs 40 and 41 with respect to the base member 7. The second surface 7a and the fourth surface 6b of the correction lens holding frame 6 rotate. Therefore, the steel ball 502 smoothly guides the movement of the correction lens holding frame 6.

  As described above, the rubber bush 503 is sandwiched by a gap having a length L1 in the Z-axis direction formed between the first surface 403a of the upper yoke 403 and the third surface 6a of the correction lens holding frame 6. Compressive elastic deformation. At this time, a pressing force B is generated in the rubber bush 503 in the Z-axis direction.

  When the rubber bush 503 is pressed against the correction lens holding frame 6 and the base member 7 and is deformed when viewed in a cross section in the direction of relative vibration between the correction lens holding frame 6 and the base member 7, the cross-sectional area is corrected. It is larger than the cross-sectional area before being pressed and deformed by the lens holding frame 6 and the base member 7. That is, the cross-sectional area S1 (shown in FIG. 8B) along the XY plane of the Z-axis central portion of the rubber bush 503 when compressively elastically deformed, and the Z-axis central portion before compressive elastic deformation The relationship with the cross-sectional area S0 (shown in FIG. 8A) along the XY plane is preferably S0 <S1. Therefore, the rubber bush 503 after compression elastic deformation has a substantially barrel shape. The elastic coefficient k (shown in FIG. 10) of the rubber bush 503 can be changed as appropriate according to the purpose.

  The rubber bushing 503 is preferably made of a material such as a non-metallic material, a polymer material, a resin, an elastomer, or rubber. For example, silicon rubber is particularly preferable in terms of control because its characteristics hardly change with temperature.

  Next, the shake correction operation will be described mainly with reference to FIGS. 9A and 9B. When the camera 100 shown in FIG. 1 is held in the horizontal direction of the optical axis, the correction lens holding frame (movable part) 6 receives gravity G as shown in FIG. At this time, even when the correction lens holding frame 6 receives gravity G due to the elastic force of the rubber bushing 503, the correction lens holding frame 6 receives only a slight displacement, and is stably placed in the approximate center of the movable range of the correction lens holding frame 6. The illustrated blur correction lens 203b is held. A shearing force is applied to the rubber bush 503, but the rubber bush 503 is only deformed by an amount proportional to the shearing force.

  In consideration of the gravity applied to the correction lens holding frame 6, the diameter of the rubber bush in the XY direction, the length L1 (shown in FIG. 7) and the material (shear stress coefficient, longitudinal elastic modulus) when assembled are set. It ’s fine. The blur correction lens 203b balances at a position displaced from the position before receiving gravity by a balance displacement amount C and stops still.

  Next, the case where the blur correction lens 203b is displaced (shifted) by the image blur correction operation will be described with reference to FIG. When the displacement in the Y-axis direction occurs in the correction lens holding frame (movable part) 6 due to the driving force D of the VCM 40 shown in FIG. 5, the rubber bush 503 is deformed while being subjected to a shearing force. Restoring force F works to restore it. The driving force D is greater than the restoring force F (+ gravity G), and the correction lens holding frame 6 moves due to the difference to perform blur correction.

  FIG. 10 shows the characteristics of the restoring force F accompanying the displacement of the rubber bush 503 and the restoring force F accompanying the displacement when a known coil spring is used. When the coil spring is used, as the displacement amount x increases, a linear proportional (linear) restoring force F having a certain inclination is generated as shown by a dotted line S in FIG. For example, the restoring force when the displacement amount is xa is Fa, and the restoring force when the displacement amount is xb is Fb ′. The elastic coefficient k has a constant value even when the displacement amount x changes.

  The characteristic of the restoring force F accompanying the displacement of the rubber bush 503 when the rubber bush 503 is used as in the present embodiment is indicated by the solid line R in FIG. That is, when the correction lens holding frame 6 is in the first range L1, the restoring force F has linearity, and when the correction lens holding frame 6 is in the second range L2 beyond the soft limit SL, the restoring force F becomes nonlinear. The increase amount of the restoring force F with respect to the increase of the displacement amount x gradually decreases. For example, the restoring force when the displacement amount is xa is Fa, and the restoring force when the displacement amount is xb is Fb. The relationship with the restoring force Fb ′ described above is Fb <Fb ′.

  As described above, the rubber bush 503 is compressed and attached between the correction lens holding frame 6 as the second member and the base member 7 as the first member, so that it is not energized (when the anti-vibration operation is not performed). ) Can effectively attenuate unnecessary vibrations of the correction lens holding frame 6 (particularly vibrations of the correction lens holding frame 6 in a direction perpendicular to the optical axis), and the centering during non-energization can be achieved with a simple configuration. It becomes possible. Further, since the rubber bush 503 has an elastic force and presses the correction lens holding frame 6 in a direction parallel to the optical axis, the correction lens holding frame 6 can be positioned with respect to the base member 7 in the optical axis direction. It is. In addition, the correction lens holding frame 6 can be shifted with a light force during the image stabilization operation, which can contribute to downsizing and power saving of the shake correction device 400.

Further, when the correction lens holding frame 6 is in the first range L1, the linearity of the relationship between the deformation amount of the rubber bush 503 and the pullback force resulting from the deformation of the rubber bush 503 is high. Accurate control is possible. Further, when the correction lens holding frame 6 is outside the first range L1 and within the second range L2, the restoring force F of the rubber bush 503 is smaller than when the coil spring is used, so that more power is saved. Control becomes possible. Further, by providing the steel ball, it is possible to guide the blur correction lens 203b so as to move smoothly in a direction orthogonal to the optical axis direction.
Second embodiment

  In the present embodiment, as shown in FIG. 11, the coil spring 505 is integrated with the rubber bush 503. Specifically, the elastic body 500 is obtained by covering the coil spring 505 with rubber or the like. Thus, except that the coil spring 505 is integrated with the rubber bush 503, it is similar to the first embodiment shown in FIGS.

  As shown in FIG. 11, the coil spring 505 and the rubber bush 503 are integrated to constitute an elastic body 500. The elastic body 500 (coil spring 505 + rubber bush 503) is compressed and elastically deformed by being sandwiched by a gap having a length L1 in the Z-axis direction formed between the upper yoke 403 and the correction lens holding frame 6. At this time, a pressing force B is generated in the elastic body 500 in the Z-axis direction.

  As shown in FIG. 10, when only the coil spring is used, a linear proportional (linear) restoring force F having a certain inclination is generated as the displacement amount x increases. As shown in FIG. 12, in this embodiment, the characteristic of the restoring force F accompanying the displacement of the elastic body 500 can be changed by the spring constant of the coil spring used. That is, the inclination of the straight line can be easily changed according to the material of the coil spring to be used, the wire diameter, the winding diameter, or the like, such as the straight line K1 to the straight line K3. The greater the spring constant of the coil spring 505, the greater the slope of the straight line.

  Further, the position of the displacement amount x at which the increasing rate of the restoring force F begins to decrease differs as shown by the dotted lines K1-1 and K1-2 shown in FIG. 12 due to a change in the material of the rubber bush 503 combined with the coil spring 505. Thus, you may design according to the objective. For example, when the correction lens holding frame 6 shown in FIG. 11 is in the above-described first range L1 (shown in FIG. 3), linearity is maintained, and the correction lens holding frame 6 is in the second range L2 shown in FIG. In some cases, it may be non-linear. In the case indicated by a dotted line K1-1, a linear region 1-1 that maintains linearity in the first range L1 is set. Further, in the case indicated by the dotted line K1-2, a linear region 1-2 that maintains linearity is set in the first range L1, and highly accurate control is performed.

As described above, since the rubber bush 503 is integrated with the coil spring 505, it is possible to easily change the inclination of the straight line between the deformation amount of the elastic body 500 and the pull back force caused by the deformation of the elastic body 500. It is possible to easily change the design according to the type and purpose of blur correction.
Third embodiment

  Since this embodiment is the same as the first embodiment shown in FIGS. 1 to 10 except for the following, a duplicate description is omitted.

  As shown in FIG. 13, the rubber bushings 5031 and 5032 are provided at substantially equal distances from the optical axis O. Moreover, from the distance L3 from the center position Ra of the rubber bushing 5031 to the optical axis O and the center position Rb of the rubber bushing 5032 along the direction (X-axis direction) orthogonal to the driving force generation direction (Y-axis direction) of the VCM 40. The distance L4 with respect to the optical axis O is substantially equal. That is, the rubber bushings 5031 and 5032 are arranged so that L3≈L4. Furthermore, the rotation angle of the rubber bushes 5031 and 5032 with respect to the optical axis O is arranged at 180 degrees. The rubber bushes 5031 and 5032 have the same configuration when viewed in a direction (Y-axis direction) orthogonal to the driving force generation direction (X-axis direction) of the VCM 41. Hereinafter, driving in the Y-axis direction is performed. Only the relationship with the VCM 40 that generates force will be described as a representative.

  If the center position of the coil constituting the VCM 40 is α, it can be considered that the driving force Fd by the VCM 40 acts on the position α. In addition, the inertial force (including gravity) acting on the position of the optical axis O of the shake correction lens 203b with respect to the driving force Fd of the VCM 40 is defined as Fo.

  As shown in FIG. 13, in the present embodiment, the driving force Fd and the inertial force Fo act almost on the same axis, so that almost no moment around the optical axis O is generated. Further, the restoring force Fra acts on the center position Ra of the rubber bush 5031 and the restoring force Frb acts on the center position Rb of the rubber bush 5032 with respect to the difference force (Fd−Fo) between the driving force Fd and the inertial force Fo. . That is, the relational expression (Fd−Fo) = Fra + Frb is established. Since L3≈L4 as described above, (Fd−Fo) / 2≈Fra≈Frb, and no unnecessary moment around the optical axis O is generated.

  In this embodiment, as shown in FIG. 14, the rubber bushes 5031 and 5032 are arranged so that the center positions (Ra and Rb) are inside a circle connecting the three steel balls 502 (502p to 502r). . The circle connecting the three steel balls 502 (502p to 502r) is, for example, a triangular circumscribed circle formed by connecting the centers of the three steel balls 502 (502p to 502r) with a straight line. The reason for this arrangement will be described with reference to FIG. 15 schematically showing the force relationship acting on the correction lens holding frame (movable part) 6 including the blur correction lens 203b.

  FIG. 15 is a schematic cross-sectional view of FIG. As shown in FIG. 15, the pressing forces fvK and fvJ by the rubber bushes 5031 and 5032 act in the optical axis Z direction, and the steel balls 502p and 502q and the steel ball 502r (see FIG. 14) receive the pressing forces fvJ and fvK. Thus, the correction lens holding frame (movable part) 6 is held. At the time of anti-vibration driving, the driving force Fd acts on the center of gravity near the optical axis O (may coincide with the optical axis O) in the shake correction lens 203b in addition to the gravity fg. Based on these forces (fg + Fd), for example, even if a moment around the point P where the steel ball 502p and the correction lens holding frame 6 are in contact with each other occurs, the force around the point P by the pressing forces fvK and fvJ by the rubber bushes 5031 and 5032 The moment can be canceled out.

  As indicated by the dotted line shown in FIG. 15, when the rubber bush 5031 ′ is outside the circle connecting the three steel balls 502 (502p to 502r), the total force (fg + Fd) of the gravity fg and the driving force Fd ) Is likely to occur in the same direction as the moment around the point P generated based on In this case, the moment around the point P generated based on the total force (fg + Fd) cannot be canceled out, and the correction lens holding frame (movable part) 6 tends to tilt, so the correction lens holding frame (movable part) 6 May not be held stably. Therefore, in this embodiment, as shown in FIG. 14, the rubber bushes 5031 and 5032 are arranged so that the center positions (Ra and Rb) are inside the circle connecting the three steel balls 502 (502p to 502r). It is preferable.

  In addition, as shown in FIG. 14, if the rubber bushings 5031 and 5032 are arranged inside the triangle having the center of the steel ball 502 (502p to 502r) as a vertex, the rubber bushings 5031 and 5032 and the steel balls 502 (502p to 502r) are arranged. The holding of the correction lens holding frame (movable part) 6 by () is further stabilized.

  Although it is preferable that the optical axis O shown in FIGS. 13 and 15 and the center of gravity of the correction lens holding frame (movable part) 6 including the blur correction lens 203b are coincident with each other, they are not necessarily coincident. .

As described above, by adopting the configuration shown in FIG. 13, when the VCMs 40 and 41 are driven, an unnecessary moment around the center of gravity or the optical axis of the correction lens holding frame (movable part) 6 is generated. Can be prevented. Therefore, it is not necessary to separately provide a guide for preventing the correction lens holding frame (movable part) 6 from rotating around the optical axis, and good drive control performance can be exhibited. Further, as shown in FIG. 14, the rubber bushings 5031 and 5032 are disposed inside the circle connecting the centers of the three steel balls 502 (502p to 502r), and are unnecessary when the VCMs 40 and 41 are driven. Generation of moment can be prevented.
Fourth embodiment

  This embodiment is the same as the first or third embodiment except that drive control is performed by three actuators 40t, 40u, and 40v as shown in FIG.

  As shown in FIG. 16, each of the driving force generation directions (T, U, V) of the actuators 40t, 40u, 40v has an intersecting angle of 120 degrees about the optical axis O. Further, the plurality of rubber bushes 503 are arranged at the center between the circumferential directions of the actuators 40t, 40u, and 40v, and their intersecting angle is also 120 degrees. The distance from the optical axis O to the rubber bush 503 is arranged to be smaller than the distance from the optical axis O to the position detection sensor 20. Further, the distance from the optical axis O to the rubber bush 503 is arranged to be smaller than the distance from the optical axis O to the steel ball 502. And the position detection sensor 20, the steel ball 502, and the rubber bush 503 are arrange | positioned in a line along the control axis. However, it is not necessarily arranged in a line along the control axis. Moreover, although the position detection sensor 20 is arrange | positioned in the outer side of the steel ball 502 in the example shown in FIG. 16, it is not limited to this. The steel ball 502 is preferably arranged at a position as far as possible from the optical axis O on the image blur correction mechanism 400.

  By disposing the rubber bush 503 in this way, the correction lens holding frame can be stably driven regardless of the number of drive control axes of the VCM.

  In the above-described embodiment, an example in which three steel balls 502 are configured has been described. However, the embodiment is not limited thereto, and may be four or more.

  In the embodiment described above, the elastic member may be ceramic. Further, it has been described that the vibration of the correction lens holding frame 6 is effectively reduced by compressing and elastically deforming the rubber bush 503, but the moving speed and acceleration of the correction lens holding frame 6 are also effectively attenuated. .

  In the above-described embodiment, the shake correction device for the shake correction lens has been described. However, the present invention is not limited to this. For example, the present invention can also be applied to a shake correction apparatus that moves an image pickup device typified by a CCD or CMOS in a plane perpendicular to the optical axis. The optical device includes, for example, a lens barrel, a camera body, a mobile phone, a telescope, and the like.

6 ... Correcting lens holding frame 7 ... Base members 40, 41, 40t, 40u, 40v ... VCM
20, 21 ... Position detection sensor 71 ... Restriction unit 203b ... Shake correction lens 403 ... Upper yoke 502, 502p, 502q, 502r ... Steel balls 503, 5031, 5032 ... Rubber bushing 505 ... Coil spring 1500 ... Calculator (MPU)

Claims (18)

An optical component for correcting image blur, and a second member that can vibrate relative to the first member;
The first member and the second member are provided between the first member and the second member and are pressed against the first member and the second member in a direction intersecting the relative vibration direction of the first member and the second member. A deformed elastic member,
The blur correction device according to claim 1, wherein the elastic member attenuates relative vibration between the first member and the second member. The blur correction device according to claim 1,
The blur correction device, wherein the elastic member includes a non-metallic material. The blur correction device according to claim 2,
The blur correction device, wherein the elastic member includes a polymer material. The blur correction device according to any one of claims 1 to 3, wherein
Relative vibration between the first member and the second member when the second member is within the first range and when the second member is within the second range outside the first range. Has a control unit capable of controlling
The elastic member is caused by the amount of deformation of the elastic member and the deformation of the elastic member when the second member is in the first range than when the second member is within the second range. A blur correction device characterized by high linearity in relation to the pull back force. The blur correction device according to claim 4,
The control unit can perform control with higher accuracy when the second member is in the first range than when the second member is in the second range, and the second member is in the second range. In some cases, the blur correction device pulls the second member back into the first range. The blur correction device according to claim 4 or 5, wherein
A blur correction device comprising a restricting portion provided outside the second range for restricting movement of the second member. The blur correction device according to any one of claims 1 to 6, wherein
The cross section of the elastic member when the first member and the second member are deformed by being pressed against the first member and the second member as viewed in a cross section in the direction of relative vibration between the first member and the second member, A blur correction device characterized by being larger than a cross-sectional area before being pressed and deformed by the first member and the second member. The blur correction device according to any one of claims 1 to 7, wherein
The blur correction device according to claim 1, wherein the elastic member has a shape in which a center side swells from an end portion when viewed in a direction intersecting a relative vibration direction of the first member and the second member. The blur correction device according to any one of claims 1 to 8,
A guide member for guiding relative vibration between the first member and the second member;
The first member has a first surface that contacts the elastic member, and a second surface that faces the first surface;
The second member has a third surface with which the elastic member contacts, and a fourth surface provided on the opposite side of the third surface,
The blur correction device according to claim 1, wherein the guide member is provided in contact with the second surface and the fourth surface. The shake correction apparatus according to claim 9, wherein
The center of the elastic member is provided inside a circle passing through the three guide members selected from the plurality of guide members. The shake correction apparatus according to claim 9 or 10, wherein
The distance from at least one of the center of gravity of the second member and the optical axis of the optical component to the elastic member is from at least one of the center of gravity of the second member and the optical axis of the optical component to the guide member. A blur correction device characterized by being shorter than the distance. The blur correction device according to any one of claims 1 to 11, wherein
There are a plurality of elastic members, and each of the plurality of elastic members is provided at a substantially equidistant position from at least one of the center of gravity of the second member and the optical axis of the optical component. Shake correction device. The blur correction device according to any one of claims 1 to 12, wherein
There are a plurality of elastic members, and each of the plurality of elastic members is provided at a position where rotation angles around the center of gravity of the second member and the optical axis of the optical component are substantially equal. A blur correction device characterized by comprising: The shake correction apparatus according to claim 13,
A plurality of driving units that generate a driving force in a driving force generation direction in order to relatively vibrate the first member and the second member;
In each of the driving force generation directions of the plurality of driving units, the rotation angle about the center of gravity of the second member and the optical axis of the optical component is substantially equal to the rotation angle of the plurality of elastic members. A blur correction apparatus characterized by the above. The blur correction device according to any one of claims 1 to 14, wherein
A driving unit that generates a driving force in a driving force generation direction to relatively vibrate the first member and the second member;
There are a plurality of elastic members, and each of the plurality of elastic members is provided at a substantially equidistant position from the center of the driving unit in a direction intersecting the driving force generation direction. Blur correction device. The blur correction device according to any one of claims 1 to 15, wherein
A detection unit for detecting relative vibration between the first member and the second member;
The distance from at least one of the center of gravity of the second member and the optical axis of the optical component to the center of the elastic member is detected from at least one of the center of gravity of the second member and the optical axis of the optical component. A blur correction device characterized by being shorter than the distance to the part. The blur correction device according to any one of claims 1 to 16, wherein
The blur correction device, wherein the elastic member is integrated with a coil spring.   An optical apparatus comprising the blur correction device according to claim 1.

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