JP2020071309A - Image blur correction device and optical equipment having the same - Google Patents

Abstract

To provide an image blur correction device that can prevent a change in optical performance and optical equipment having the image blur correction device.SOLUTION: An image blur correction device comprises: a movable member having a lens for blur correction; a first base member supporting the movable member so as to be movable in a plane perpendicular to an optical axis of a lens; a ball member held between the first base member and the movable member; and a second base member fixed on the first base member at a plurality of fixing positions so as to sandwich the first base member and the movable member in the optical axis direction of the lens. The first base member and the movable member are energized via the ball member in the holding direction. The second base member is fixed on the first base member with a screw at a first fixing position that is the farthest from the lens and fixed on the first base member with adhesive at at least one of fixing positions other than the first fixing position.SELECTED DRAWING: Figure 7

Description

  The present invention relates to an image blur correction device capable of suppressing image blur caused by camera shake and the like, and an optical apparatus including the same.

  2. Description of the Related Art Conventionally, there is known an image blur correction device that is mounted on a camera or an interchangeable lens, detects a shake such as a camera shake, and moves the lens in a direction orthogonal to an optical axis according to the detection result (see Patent Document 1). ..

JP, 2014-74828, A

  In the image blur correction device of Patent Document 1, when the shift base barrel and the attachment member for the damping member are fixed by the three screws, the shift base barrel is deformed and the shift barrel collapses. As a result, the optical performance changes.

  It is an object of the present invention to provide an image blur correction device capable of suppressing a change in optical performance and an optical device including the same.

  An image blur correction device according to one aspect of the present invention includes a movable member including a lens for image blur correction, a first base member that supports the movable member so as to be movable in a plane orthogonal to an optical axis of the lens, and a first base member. A ball member sandwiched between the base member and the movable member, and a second base fixed to the first base member at a plurality of fixed positions so as to sandwich the first base member and the movable member in the optical axis direction of the lens. The first base member and the movable member are urged in a direction of sandwiching them through the ball member, and the second base member is the first fixed position farthest from the lens. It is characterized in that it is fixed to the base member and is fixed to the first base member with an adhesive agent in at least one fixing position among fixing positions different from the first fixing position.

  According to the present invention, it is possible to provide an image blur correction device capable of suppressing a change in optical performance and an optical apparatus including the same.

FIG. 1 is a perspective view of a video camera that is an example of an optical device according to an embodiment of the present invention. It is a schematic diagram of a lens barrel. It is a perspective view of a vibration isolation unit. It is the figure which looked at the antivibration unit from the front lens side. It is sectional drawing of a vibration isolation unit. It is a figure which shows the positional relationship between a shift base lens barrel and a ball. It is the figure which looked at the image stabilization unit from the imaging surface side. FIG. 8 is a schematic view of the image stabilizing unit viewed from a direction 4d8 in FIG. 7.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In each drawing, the same reference numerals are given to the same members, and duplicate description will be omitted.

  FIG. 1 is a perspective view of a video camera 1 which is an example of an optical device according to an embodiment of the present invention. The video camera 1 has a lens barrel L and a camera body B. If the photographer shakes the camera while holding the camera body B and takes a picture, the taken image will be blurred. At that time, a gyro sensor (not shown) in the camera body B detects camera shake, and an anti-vibration lens (not shown) in the lens barrel L operates in a direction (pitch direction and yaw direction) orthogonal to the optical axis. The camera shake can be corrected and the blurring that occurs in the image can be suppressed.

  The optical device to which the present invention can be applied is not limited to the video camera 1, but the present invention can be applied to an optical device such as an imaging device such as a digital still camera or an interchangeable lens.

  FIG. 2 is a schematic diagram of the lens barrel L. The lens barrel L has an imaging optical system including a first lens unit L1, a second lens unit L2, a third lens unit L3, and a fourth lens unit L4. The first lens unit L1 is fixed. The second lens unit L2 performs a zooming operation by moving along the optical axis of the imaging optical system. The third lens unit L3 performs the zooming operation by moving along the optical axis, and also performs the image stabilizing operation by moving in the direction orthogonal to the optical axis. The fourth lens unit L4 performs a focusing operation by moving along the optical axis.

  The imaging element 20 images the light flux that has passed through the imaging optical system. The output signal from the image pickup device 20 is subjected to various signal processes in the camera signal processing circuit 201 and converted into a video signal. The video signal is displayed on a display (not shown) or recorded on a recording medium (semiconductor memory, optical disk, hard disk, magnetic tape, etc.) not shown through the microcomputer 202.

  The microcomputer 202 outputs signals from the zoom reset circuit 206 that detects the reference positions of the second lens unit L2 and the third lens unit L3 in the optical axis direction and the focus position detection circuit 205 that detects the positions of the fourth lens unit L4. To receive. Then, the microcomputer 202 controls the zoom motor drive circuit 204 and the focus drive circuit 203 with reference to the received signal to perform zoom drive and focus drive. Further, the microcomputer 202 controls the aperture unit driving circuit 207 based on the luminance signal component of the video signal to change the aperture diameter of the light amount adjusting unit 3 to a size corresponding to the appropriate light amount.

  The microcomputer 202 receives the shake signals from the pitch shake sensor 215 and the yaw shake sensor 216 such as a vibration gyro, and based on the received shake signals, the shift lens in the third lens unit L3 moves in the pitch direction and the yaw direction. Calculate the target drive position. Further, the microcomputer 202 receives information on the position (detection position) of the shift lens from the pitch position detection circuit 213 and the yaw position detection circuit 214 which respectively include a first hall element and a second hall element (not shown). Then, the microcomputer 202 energizes the first drive coil and the second drive coil (not shown) through the pitch coil drive circuit 211 and the yaw coil drive circuit 212 so that the received detection position reaches the target drive position. To control. As a result, image blur correction (image stabilization) is performed.

  Hereinafter, the image stabilization unit (image blur correction device) 100 will be described. FIG. 3 is a perspective view of the image stabilization unit 100. 3A and 3B are a view seen from the front lens side and a view seen from the imaging surface side, respectively. FIG. 4 is a view of the image stabilizing unit 100 viewed from the front lens side. FIG. 5 is a cross-sectional view of the vibration isolation unit 100. 5A to 5C are a sectional view taken along the line AA, a sectional view taken along the line BB, and a sectional view taken along the line CC of FIG. 4, respectively. FIG. 6 is a diagram showing the positional relationship between the shift base barrel and the balls as seen from the front lens side.

  The shift lens barrel (movable member) 5 holds a shift lens for shake correction in the third lens unit L3. The shift base barrel (first base member) 4 movably supports the shift barrel 5 in a plane orthogonal to the optical axis.

  In this embodiment, three coil springs 16 are provided. A first end of the coil spring 16 is hooked on the shift base barrel 4, and a second end thereof is hooked on the shift barrel 5. The balls (ball members) 17a, 17b, 17c are sandwiched between the shift base barrel 4 and the shift barrel 5. The shift base 4 and the shift lens barrel 5 are urged by the coil spring 16 in a direction in which they are sandwiched via the balls 17a to 17c. The shift barrel 5 moves only by the rolling friction of the balls 17a to 17c.

  The pitch drive magnet 9a includes two magnets each having one pole magnetized in the optical axis direction and fixed to the shift base barrel 4. The two magnets are arranged along the direction perpendicular to the optical axis. The pitch yoke material 10a is fixed to the shift base barrel 4 and closes the magnetic flux generated from the pitch drive magnet 9a. The pitch drive coil 8a is arranged at a position facing the pitch drive magnet 9a, and is fixed to the shift barrel 5 with an adhesive agent (not shown).

  When a voltage is applied to the pitch drive coil 8a, a driving force is generated between the pitch drive coil 8a and the pitch drive magnet 9a in the L3a direction perpendicular to the optical axis in FIG. 5A. This driving force is controlled by the magnitude and direction (polarity) of the voltage applied to the pitch driving coil 8a.

  The yaw drive magnet 9b includes two magnets each having one pole magnetized in the optical axis direction and fixed to the shift base barrel 4. The two magnets are arranged along the direction perpendicular to the optical axis. The yaw yoke material 10b is fixed to the shift base barrel 4 and closes the magnetic flux generated from the yaw drive magnet 9b. The yaw drive coil 8b is arranged at a position facing the yaw drive magnet 9b, and is fixed to the shift barrel 5 with an adhesive agent (not shown).

  When a voltage is applied to the yaw drive coil 8b, a drive force is generated between the yaw drive coil 8b and the yaw drive magnet 9b in the L3b direction perpendicular to the optical axis in FIG. 5B. This driving force is controlled by the magnitude and direction (polarity) of the voltage applied to the yaw driving coil 8b.

  The pitch position detection sensor 15a is fixedly arranged inside the pitch drive coil 8a. The yaw position detecting sensor 15b is fixedly arranged inside the yaw drive coil 8b. Hall elements are used for the pitch position detection sensor 15a and the yaw position detection sensor 15b, for example, and they function as position detection sensors.

A pitch position detecting sensor 15a and a yaw position detecting sensor 15b are mounted on the flexible printed board 14 by soldering. The flexible printed board 14 is soldered to the coil terminals of the pitch drive coil 8a and the yaw drive coil 8b, and is electrically connected to these coils. In the present embodiment, a so-called moving coil type drive mechanism in which the pitch drive coil 8a and the yaw drive coil 8b are adhesively fixed to the shift barrel 5 is configured. Therefore, the flexible printed circuit board 14 is drawn from the shift lens barrel 5 to the shift base lens barrel 4 in an arc shape and then fixed on the shift base lens barrel 4 side. The flexible pressing sheet metal 11 suppresses the bulging of the flexible printed circuit board 14 and is fixed to the shift base barrel 4 with screws by screws 12. The flexible press plate 11 may be fixed to the shift base lens barrel 4 without using the screw 12. The damping means attachment member (second base member) 6 is provided with the shift base lens barrel 4 in the optical axis direction. It is fixed to the shift base barrel 4 at a plurality of fixing positions so as to sandwich the shift barrel 5. The damping means 7a is provided in order to make the antivibration unit 100 less susceptible to resonance due to external disturbances, in other words, to obtain a damper effect for improving the controllability of the antivibration unit 100. Although various viscoelastic bodies can be used as the damping means 7a, in the present embodiment, an ultraviolet curable silicone gel having excellent assembling property and environment resistance is used. For example, a transparent PET sheet is used as the transparent sheet 7b.

  Hereinafter, the procedure for assembling the vibration isolation unit 100 will be described. First, the pitch drive coil 8a and the yaw drive coil 8b are adhesively fixed to the shift barrel 5. After that, the flexible printed circuit board 14 on which the pitch position detecting sensor 15a and the yaw position detecting sensor 15b are mounted by soldering is adhesively fixed to the shift barrel 5. Next, as shown in FIG. 6, the balls 17a to 17c are placed in the concave portion 4a of the shift base barrel 4 to which the magnet and the yoke are fixed. After that, the shift barrel 5 to which the coil and the flexible printed circuit board 14 are bonded and fixed is assembled to the shift base barrel 4, and the coil spring 16 is assembled to the shift base barrel 4 and the shift barrel 5. Next, the damping means mounting member 6 is fixed to the shift base barrel 4.

  Hereinafter, a method of fixing the damping means mounting member 6 to the shift base lens barrel 4 will be described with reference to FIG. 7. FIG. 7 is a view of the image stabilizing unit 100 immediately after the damping unit mounting member 6 is mounted on the shift base lens barrel 4, as viewed from the imaging surface side. The ball placement positions 4d1, 4d2, 4d3 respectively indicate the positions of the balls 17c, 17a, 17b as viewed in the optical axis direction.

  The damping means mounting member 6 is provided with three boss shapes for screwing the shift base lens barrel 4. When fixing the damping means mounting member 6 to the shift base lens barrel 4, first, the damping means mounting member 6 is screwed to the shift base lens barrel 4 with screws 13a, 13b, 13c. After that, the screws 13b and 13c are rotated in the reverse rotation direction, and the fastening state between the shift base barrel 4 and the damping means mounting member 6 by the screws 13b and 13c is loosened. The amount of rotation of the screws 13b and 13c is preferably, for example, half rotation to one rotation. When the screws are tightened, the shift base lens barrel 4 is deformed by the tightening torque, but by loosening the screws at a plurality of fixed positions, the shift base lens barrel 4 can be prevented from being deformed. After that, the adhesives 4b and 4c are applied to the screw head portions of the screws 13b and 13c, respectively. This prevents the screws 13b and 13c from rotating from the position before the application of the adhesive. As the adhesive, for example, a UV adhesive or a rubber adhesive is used.

  In the present embodiment, the damping means mounting member 6 is fixed to the shift base barrel 4 at three fixing positions. Since the two screws 13b, 13c other than the screw 13a among the screws 13a, 13b, 13c are loosened, the screw actually mounting the damping means mounting member 6 to the shift base barrel 4 is only the screw 13a. is there. In the present embodiment, the position where the damping means mounting member 6 is screwed to the shift base barrel 4 among the plurality of fixed positions is referred to as a first fixed position. At the first fixed position, the damping means mounting member 6 is not fixed to the shift base barrel 4 with an adhesive. Further, at a fixing position different from the first fixing position, since the screws are loosened and then adhered by the adhesive, the damping means attaching member 6 is substantially adhered and fixed to the shift base barrel 4. There is. In this embodiment, at a fixing position different from the first fixing position, the screw is removed, and the adhesive is directly applied to the position of the screw to fix the damping means mounting member 6 to the shift base lens barrel 4 by adhesion. May be.

  Then, the damping means 7a is injected into the cylindrical portion 6a provided on the damping means mounting member 6. Finally, the flexible pressing sheet metal 11 is fixed by the screws 12, so that the vibration isolation unit 100 is completed.

  The first fixed position will be described below. In the present embodiment, the balls 17a to 17c are arranged such that the triangle 4d4 formed by connecting the ball arrangement positions 4d1 to 4d3 does not become an equilateral triangle when viewed in the optical axis direction. Therefore, when a perpendicular is drawn from an arbitrary vertex of the triangle 4d4 to the opposite side, a relatively long perpendicular and a short perpendicular exist. Vertical lines 4d5, 4d6, 4d7 are vertical lines drawn from the ball placement positions 4d2, 4d3, 4d1 to the opposite sides, respectively. The longest perpendicular of the three perpendiculars is the perpendicular 4d5, and the shortest perpendicular is the perpendiculars 4d6 and 4d7 (the perpendiculars 4d6 and 4d7 have the same length).

  FIG. 8 is a schematic view of the image stabilizing unit 100 viewed from a direction 4d8 orthogonal to the perpendicular line 4d5 of FIG. When the anti-vibration unit 100 is viewed from the direction 4d8, the balls 17b and 17c appear to overlap. If the position of the receiving surface of the ball 17a in the optical axis direction is displaced by the displacement amount 4d9 due to the deformation of the shift base lens barrel 4 due to the screwing, the tilt amount of the shift base lens barrel 4 becomes the tilt amount 4d10. At this time, the longer the length 4d50 of the perpendicular 4d5 is, the smaller the tilt amount 4d10 is. The relationship between the tilt amount 4d10, the displacement amount 4d9, and the length 4d50 of the perpendicular 4d5 is expressed by the following equation (1).

4d10 = atan (4d9 / 4d5) (1)
As represented by the equation (1), when the displacement amount 4d9 does not change, the longer the length 4d50 of the perpendicular line 4d5 is, the smaller the tilt amount 4d10 is.

  Therefore, in the present embodiment, the first fixed position is the position closest to the ball placement position 4d2 among the ball placement positions 4d1 to 4d3. That is, when a perpendicular line is drawn from any apex of the triangle 4d4 to the opposite side, the damping means attaching member 6 shifts at a position close to the apex position corresponding to the longest perpendicular line (in the present embodiment, the ball arrangement position 4d2). It is screwed to the base lens barrel 4. Further, since the ball arrangement position 4d2 can be said to be the farthest position from the shift lens in the third lens unit L3, setting the first fixed position to the above-mentioned position is farthest from the shift lens in the third lens unit L3. It has the same meaning as setting the position.

  As described above, in the present embodiment, at the first fixed position, the damping means mounting member 6 is screwed to the shift base barrel 4, and at least a part of the fixed positions different from the first fixed position is fixed. Then, the attenuator mounting member 6 is adhesively fixed to the shift base barrel 4. With such a configuration, even if the shift base lens barrel 4 is deformed by screwing, the influence of the deformation of the shift base lens barrel 4 on the tilt of the shift lens barrel 5 can be minimized.

  Further, in the present embodiment, the vibration isolation unit 100 can be moved along the optical axis by the driving force of a stepping motor (not shown). In FIGS. 3A and 3B, the guide bars 1a and 1b are fixedly arranged parallel to the optical axis. The vibration isolation unit 100 is movable along the guide bars 1a and 1b. The guide bar 1a is fitted to the sleeve shape (sleeve portion) 4e of the shift base barrel 4. The sleeve shape 4e has a shape extending in the optical axis direction, and the longer the sleeve shape 4e, the more the tilting of the vibration isolation unit 100 with respect to the optical axis can be suppressed. The guide bar 1b is fitted with the rotation restricting portion 4f of the shift base barrel 4.

  The lead screw 2b, which is the output shaft of the stepping motor, is connected to the rack 2a. The rotational force of the lead screw 2b is converted into a force that moves back and forth in the optical axis direction by the rack 2a. As a result, the shift base barrel 4 connected to the rack 2a moves back and forth in the optical axis direction.

  As described above, the damping means mounting member 6 is fixed to the shift base barrel 4 at three fixing positions. In the present embodiment, at the fixed position farthest from the sleeve shape 4e (hereinafter, the second fixed position), the damping means mounting member 6 is screwed to the shift base barrel 4 by the screw 13a. This is to prevent the shift base barrel 4 from falling due to the deformation of the sleeve shape 4e caused by the screwing. If the damping means attachment member 6 is adhesively fixed to the shift base barrel 4 at the second fixed position, the damping means attachment member 6 is fixed at the fixed position where the screw 13b closer to the second fixed position is used. The case of fixing with screws will be described. In this case, the stress due to the screw tightening affects the sleeve shape 4e, and the sleeve shape 4e falls, and the angular relationship between the sleeve shape 4e and the three receiving surfaces of the balls 17a to 17c is broken. As a result, the shift barrel 5 and the third lens unit L3 are tilted with respect to the optical axis, and the optical performance is changed. Therefore, by fixing the attenuator mounting member 6 to the shift base lens barrel 4 with a screw at the position farthest from the sleeve shape 4e among the fixed positions, the deformation due to the screw fixing gives the tilt of the third lens unit L3. It is possible to minimize the influence.

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

4 Shift base lens barrel (first base member)
4b, 4c Adhesive 5 Shift lens barrel (movable member)
6 Damping means mounting member (second base member)
17a-17c Ball (ball member)
13a screw

Claims (8)

A movable member having a lens for shake correction,
A first base member for movably supporting the movable member in a plane orthogonal to the optical axis of the lens;
A ball member sandwiched between the first base member and the movable member;
A second base member fixed to the first base member at a plurality of fixing positions so as to sandwich the first base member and the movable member in the optical axis direction of the lens,
The first base member and the movable member are urged in a direction of sandwiching them via the ball member,
The second base member is fixed to the first base member by a screw at a first fixing position farthest from the lens, and is bonded at least at one fixing position different from the first fixing position. An image blur correction device fixed to the first base member with an agent.   The image blur correction device according to claim 1, wherein the second base member is not fixed to the first base member by an adhesive at the first fixing position.   The image blur correction device according to claim 1, wherein the second base member is fixed to the first base member with an adhesive at a fixing position different from the first fixing position.   The image blur correction device according to claim 3, wherein the second base member is fixed to the first base member with an adhesive and a screw at a fixing position different from the first fixing position. The first base member includes a sleeve portion that fits with a guide bar parallel to the optical axis, and is movable along the guide bar,
The image blur correction device according to claim 1, wherein the second base member is fixed to the first base member with a screw at a second fixing position farthest from the sleeve portion.   The image blur correction device according to claim 5, wherein the second base member is not fixed to the first base member by an adhesive at the second fixing position. A movable member having a lens for shake correction,
A first base member for movably supporting the movable member in a plane orthogonal to the optical axis of the lens;
A ball member sandwiched between the first base member and the movable member;
A second base member fixed to the first base member at a plurality of fixing positions so as to sandwich the first base member and the movable member in the optical axis direction of the lens,
The first base member and the movable member are urged in the direction of sandwiching via the ball member,
The first base member includes a sleeve portion that fits with a guide bar parallel to the optical axis, and is movable along the guide bar,
The second base member is fixed to the first base member by a screw at a second fixed position farthest from the sleeve portion, and at least one fixed position among fixed positions different from the second fixed position, An image blur correction device fixed to the first base member with an adhesive. An image blur correction device according to any one of claims 1 to 7,
An optical device comprising: an image pickup element that picks up an image of a light flux that has passed through an image pickup optical system.