Optical element driving device, camera module, and camera-mounted device

Abstract

To increase thrust for driving an optical element and allow downsizing.SOLUTION: An optical element driving device comprises: a first movable part configured to be movable in an optical axis direction by a first drive part with an optical element being held; and a second movable part configured to be movable with the first movable part in a direction orthogonal to the optical axis direction by a second drive part, the second movable part configured on a base by stacking a first stage and a second stage. The second drive part is arranged along the orthogonal side faces of the second movable part, and the first drive part is arranged on each of diagonal positions of the second movable part.SELECTED DRAWING: Figure 14

Description

[Technical Field]

[0001] The present invention relates to an optical element driving device that drives an optical element, a camera module, and a camera-mounted device. [Background technology]

[0002] Generally, a camera module is mounted on a thin camera-equipped device such as a smartphone, and an optical element driving device for driving an optical element is used in such a camera module.

[0003] The optical element driving device has an autofocus function (hereinafter referred to as the "AF function"). The optical element driving device uses the AF function to drive the lens (optical element) and automatically adjust the focus when photographing a subject.

[0004] For example, Patent Document 1 discloses a lens driving device that includes a lens holder that holds a lens, a ball member that supports the lens holder so that it can move in the optical axis direction, and one actuator that drives the lens holder so that it can move in the optical axis direction. In Patent Document 1, the one actuator is disposed at one corner of a base that is rectangular in plan view. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2013-068828 Summary of the Invention [Problem to be solved by the invention]

[0006] In recent years, as camera modules have become increasingly high-pixel count, the size and weight of the lenses and sensors in the camera modules have tended to increase. As described above, in Patent Document 1, a single actuator drives the lens and lens holder. Therefore, as the weight of the lens increases, the thrust force for driving the lens becomes insufficient, potentially resulting in problems such as a longer focusing time. While the thrust force for driving the lens can be increased by providing multiple actuators, this makes it difficult to miniaturize the camera module. Therefore, there is a demand for an optical element driving device that can increase the thrust force for driving the lens while also achieving miniaturization.

[0007] An object of the present invention is to provide an optical element driving device, a camera module, and a camera-mounted device that can increase the thrust force for driving an optical element and can be made smaller. [Means for solving the problem]

[0008] The optical element driving device according to the present invention comprises: a first movable section configured to be movable in the optical axis direction by a first driving section while holding the optical element; a fixed portion having an opening in which the first movable portion is disposed and having a rectangular shape in a plan view from the optical axis direction; support portions disposed at at least three circumferentially dispersed positions inside the opening, and configured to support the first movable portion movably in the optical axis direction; Equipped with one of the support portions has an elastic member that presses the first movable portion toward the inside of the opening, and is disposed at a portion corresponding to a first corner portion of four corner portions of the fixed portion; The other support portions are arranged in portions avoiding the four corner portions, The first driving unit is disposed at a diagonal position corresponding to a second corner and a third corner that sandwich the first corner among the four corners. , symmetrical with respect to the direction of pressure by the elastic member They are placed respectively.

[0009] The camera module according to the present invention comprises: the optical element driving device; an imaging unit that captures a subject image formed by the optical element; Equipped with.

[0010] The camera-equipped device according to the present invention comprises: A camera-equipped device that is an information device or a transportation device, the camera module; an image processing unit that processes image information obtained by the camera module; Equipped with. [Effects of the Invention]

[0011] According to the present invention, in the optical element driving device, it is possible to increase the thrust force for driving the optical element and to achieve miniaturization. [Brief explanation of the drawings]

[0012] [Figure 1A] 1 is a front view showing a smartphone equipped with a camera module according to an embodiment of the present invention. [Figure 1B] FIG. 1B is a rear view of the smartphone shown in FIG. 1A. [Figure 2] FIG. 2 is a perspective view showing a camera module and an imaging unit. [Figure 3] 1 is a perspective view of an optical element driving device main body of an optical element driving device of a camera module. FIG. [Figure 4] 4 is a perspective view of the optical element driving device main body shown in FIG. 3, seen from a different direction. FIG. [Figure 5] FIG. 5 is an exploded perspective view of the optical element driving device main body shown in FIGS. 3 and 4. [Figure 6] FIG. 6 is an exploded perspective view of the OIS movable part shown in FIG. 5. [Figure 7] FIG. 5 is a plan view of the optical element driving device main body shown in FIGS. 3 and 4. [Figure 8] FIG. 2 is a plan view showing the positional relationship between an OIS fixed section and an AF movable section. [Figure 9] FIG. 2 is a plan view of the OIS fixing portion. [Figure 10] FIG. 2 is a bottom view of the OIS fixing part. [Figure 11] FIG. 2 is a bottom view of the OIS movable part. [Figure 12] FIG. 2 is a bottom view of the AF movable portion and the first stage. [Figure 13] FIG. [Figure 14] FIG. 2 is a plan view schematically showing the optical element driving device main body. [Figure 15A] 1 is a front view showing an automobile as a camera-mounted device equipped with an in-vehicle camera module. [Figure 15B] FIG. 15B is a perspective view of the automobile shown in FIG. 15A as seen obliquely from the rear side. DETAILED DESCRIPTION OF THE INVENTION

[0013] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

[0014] [Smartphone] 1A and 1B are diagrams showing a smartphone M (an example of a camera-equipped device) equipped with a camera module A according to the present embodiment, in which Fig. 1A is a front view of the smartphone M and Fig. 1B is a rear view of the smartphone M.

[0015] The smartphone M has a dual camera system consisting of two rear cameras OC1 and OC2. In this embodiment, the camera module A is applied to the rear cameras OC1 and OC2.

[0016] Camera module A has an AF function and an image stabilization function (hereinafter referred to as the "OIS function": Optical Image Stabilization). Camera module A uses the AF function to automatically focus when photographing a subject, and the OIS function optically corrects shake (vibration) that occurs during photography, enabling images to be taken without image blur.

[0017] [Camera module] FIG. 2 is a perspective view showing the camera module A and the imaging unit 5. FIGS. 3 and 4 are perspective views of the optical element driving device main body 4 of the optical element driving device 1 of the camera module A shown in FIG. 2. FIG. 4 is a view of the optical element driving device main body 4 shown in FIG. 3 rotated 180° around the Z axis. As shown in FIGS. 2 to 4, this embodiment will be described using a Cartesian coordinate system (X, Y, Z). The same Cartesian coordinate system (X, Y, Z) is also used in the drawings described below.

[0018] For example, when a smartphone M is used to take a photograph, the camera module A is mounted so that the X direction is the up-down direction (or left-right direction), the Y direction is the left-right direction (or up-down direction), and the Z direction is the front-rear direction. That is, the Z direction is the optical axis direction, and in Figures 2 to 4, the upper side (+Z side) in the figure is the light-receiving side in the optical axis direction, and the lower side (-Z side) is the image-forming side in the optical axis direction. Furthermore, hereinafter, the X and Y directions orthogonal to the Z axis are referred to as "directions orthogonal to the optical axis," and the XY plane is referred to as "plane orthogonal to the optical axis." Furthermore, the direction orthogonal to the optical axis is referred to as "radial direction."

[0019] 2, the camera module A includes an optical element driving device 1 that realizes the AF function and the OIS function, a lens unit 2 configured by housing a lens in a cylindrical lens barrel, and an imaging unit 5 that captures a subject image formed by the lens unit 2. In other words, the optical element driving device 1 is a so-called lens driving device that drives the lens unit 2 as an optical element.

[0020] [cover] In the optical element driving device 1, the optical element driving device main body 4 is covered on the outside with a cover 3. The cover 3 is a covered square cylinder that is rectangular in plan view when viewed from the optical axis direction. In this embodiment, the cover 3 has a square shape in plan view. The cover 3 has a substantially circular opening 301 on its upper surface. The lens unit 2 is housed in the opening 401 of the optical element driving device main body 4, faces the outside through the opening 301 of the cover 3, and is configured to protrude beyond the opening surface of the cover 3 toward the light receiving side in the optical axis direction as the lens unit 2 moves in the optical axis direction, for example. The inner wall of the cover 3 is fixed to the base 21 (see FIG. 5 described later) of the OIS fixing unit 20 of the optical element driving device main body 4, for example, by adhesive, and houses the OIS movable unit 10 and the like (see FIG. 5) inside together with the base 21.

[0021] The cover 3 includes a member that blocks electromagnetic waves from the outside of the optical element driving device 1, for example, a shielding member made of a magnetic material.

[0022] [Image capture unit] The imaging unit 5 is arranged on the imaging side in the optical axis direction of the optical element driving device 1. The imaging unit 5 has, for example, an image sensor board 501, an imaging element 502 mounted on the image sensor board 501, and a control unit 503. The imaging element 502 is configured with, for example, a CCD (charge-coupled device) type image sensor, a CMOS (complementary metal oxide semiconductor) type image sensor, or the like, and captures the subject image formed by the lens unit 2.

[0023] The control unit 503 is configured by, for example, a control IC, and controls the driving of the optical element driving device 1. The optical element driving device 1 is mounted on the image sensor substrate 501 and is mechanically and electrically connected thereto. The control unit 503 may be provided on the image sensor substrate 501, or may be provided in a camera-equipped device (in this embodiment, a smartphone M) on which the camera module A is mounted.

[0024] [Optical element driving unit] Fig. 5 is an exploded perspective view of the optical element driving device main body 4. Fig. 6 is an exploded perspective view of the OIS movable part 10. Fig. 7 is a plan view of the optical element driving device main body 4. The optical element driving device main body 4 will be described with reference to Figs. 5 to 7.

[0025] As shown in FIG. 5, the optical element driving device main body 4 includes an OIS movable portion 10, an OIS fixed portion 20, an OIS driving portion 30, an OIS support portion 40, and an OIS biasing member 50.

[0026] The OIS movable section 10 is capable of holding the lens section 2 and is a section that swings in a plane perpendicular to the optical axis during shake correction. Although details will be described later, the OIS movable section 10 has an AF section 11, a second stage 14, and an OIS support section 40 (Y-direction reference ball 42) (see FIG. 6). Similarly, although details will be described later, the AF section 11 has an AF movable section 12, a first stage 13, an AF drive section 15, and AF support sections 16A and 16B (see FIGS. 5 and 6).

[0027] 5, the OIS fixing section 20 has a base 21 and an OIS support section 40 (X-direction reference ball 41). The OIS fixing section 20 is disposed via the OIS support section 40 at a position spaced apart from the OIS movable section 10 in the optical axis direction, and supports the OIS movable section 10 via the OIS support section 40 so that the OIS movable section 10 can swing in a direction perpendicular to the optical axis. In other words, the OIS movable section 10 is disposed via the X-direction reference ball 41 at a position spaced apart from the base 21 in the optical axis direction, and the base 21 supports the OIS movable section 10 via the X-direction reference ball 41 so that the OIS movable section 10 can swing.

[0028] Furthermore, the OIS movable unit 10 and the OIS fixed unit 20 are elastically connected by OIS biasing members 50 so as to bias them in directions toward each other, in other words, so as to maintain a state in which the OIS support unit 40 is sandwiched between them (see FIGS. 3 to 5). The OIS biasing members 50 are made of a conductive material. As will be described in detail later, the OIS biasing members 50 also function as connecting members that form a conductive path between a circuit for driving the lens unit 2 and the like and a circuit on the OIS fixed unit 20 side. In this embodiment, the OIS biasing members 50 are arranged at the four corners of the optical element driving device main body 4 in a plan view (see FIGS. 3 and 4).

[0029] Although details will be described later, the OIS driver 30 has a first OIS driver 30X that drives the OIS movable part 10 in the X direction, and a second OIS driver 30Y that drives the OIS movable part 10 in the Y direction.

[0030] In this embodiment, with respect to movement in the X direction, the entire OIS movable section 10 including the AF section 11 moves as a movable body. That is, with respect to movement in the X direction, the base 21 of the OIS fixed section 20 constitutes the fixed body, and the X-direction reference ball 41 functions as the OIS support section 40 that supports the OIS movable section 10 so that it can swing in the X direction.

[0031] Meanwhile, with regard to movement in the Y direction, the AF unit 11 moves as a movable body, as will be described in detail later with reference to Fig. 6. In other words, with regard to movement in the Y direction, the second stage 14 constitutes a fixed body together with the base 21, and the Y-direction reference ball 42 functions as an OIS support unit 40 that supports the AF unit 11 so that it can swing in the Y direction.

[0032] [OIS fixed part] Fig. 9 is a plan view of the OIS fixing portion 20. Fig. 10 is a bottom view of the OIS fixing portion 20. The OIS fixing portion 20 will be described with reference to Figs.

[0033] The OIS fixing section 20 has a base 21, a substrate 22, a first OIS driving section 30X, and an OIS supporting section 40 (X-direction reference ball 41) (see FIG. 5).

[0034] [Base, OIS support] The base 21 is formed from a molding material such as polyarylate (PAR), a PAR alloy (e.g., PAR / PC) made by mixing multiple resin materials including PAR, or a liquid crystal polymer. The base 21 is a rectangular member in a plan view and has a circular opening 211 in the center.

[0035] The base 21 has an OIS motor fixing portion 217 on which the first OIS driving unit 30X is disposed. The OIS motor fixing portion 217 is provided, for example, near one corner of the base 21, and is formed to protrude from the base 21 toward the light receiving side in the optical axis direction, and has a shape that can hold the first OIS driving unit 30X (see FIG. 5).

[0036] The base 21 also has an X-direction reference ball holder 218 that holds the X-direction reference ball 41 that constitutes the OIS support part 40. The X-direction reference ball 41 is sandwiched between the X-direction reference ball holder 218 and an X-direction reference ball holder 144 (see FIG. 11 described later) of the second stage 14 that face each other in the Z direction.

[0037] The X-direction reference ball holding portion 218 and the X-direction reference ball holding portion 144 are recesses having rectangular openings extending in the X-direction. The X-direction reference ball holding portion 218 and the X-direction reference ball holding portion 144 are formed so that the groove width narrows toward the bottom of the recess, for example, so that the cross section has a substantially V-shape (tapered shape) or a substantially U-shape.

[0038] The groove formed by the recess having the above-described cross-sectional shape is formed parallel to the X direction, so that the X-direction reference ball 41 held between the X-direction reference ball holding part 218 and the X-direction reference ball holding part 144 can roll in the X direction within the recess. In other words, the base 21 supports the OIS movable part 10 (second stage 14) via the X-direction reference ball 41 so that the OIS movable part 10 can move in the X direction.

[0039] The X-direction reference ball holder 218 and the X-direction reference ball holder 144 are arranged at the four corners of the rectangular base 21 and second stage 14, and the OIS movable part 10 (second stage 14) is supported by the four X-direction reference balls 41, that is, at four points, on the base 21. In this way, the X-direction reference ball 41 is held by multi-point contact and therefore rolls stably in the Y direction.

[0040] The OIS movable part 10 (second stage 14) may be supported by the base 21 at at least three points. For example, when supported at three points, the X-direction reference ball holder 218 and the X-direction reference ball holder 144 may be disposed at a total of three locations: two locations on one side of the base 21 and the second stage 14 and one location on the side opposite that side.

[0041] A plurality of terminals 23 and power supply lines 25Xa, 25Xb, 25Ya, 25Yb, 25Za, 25Zb, 25Zc, and 25Zd are arranged on the outer edge of the base 21 (see FIGS. 9 and 10).

[0042] The terminals 23 are embedded in the base 21 by, for example, insert molding, and are formed so that one end of each terminal is exposed from the top surface of the base 21 (see FIG. 9) and the other end is exposed from the bottom surface of the base 21 (see FIG. 10). The terminals 23 are terminals for supplying power and signals to driver ICs 221X, 221Y, and 221Z (described below) that drive the first OIS drive unit 30X, the second OIS drive unit 30Y, and the AF drive unit 15, respectively.

[0043] The power supply wirings 25Xa and 25Xb are formed at the outer edge of the base 21, from their inner ends to their outer ends, so as to be exposed on the top surface of the base 21 (see FIG. 9). The power supply wirings 25Ya and 25Yb are formed at the corners that are the outer edge of the base 21, so that their inner ends are exposed on the top surface of the base 21 (see FIG. 9) and their outer ends are exposed on the bottom surface of the base 21 (see FIG. 10). The power supply wirings 25Za, 25Zb, 25Zc, and 25Zd are formed at the corners that are the outer edge of the base 21, so that their inner ends are exposed on the top surface of the base 21 (see FIG. 9) and their outer ends are exposed on the bottom surface of the base 21 (see FIG. 10).

[0044] The inner ends of the power supply wires 25Xa and 25Xb are connected to the substrate 22 and are connected to the driver IC 221X via a booster unit 60, which will be described later. The outer ends of the power supply wires 25Xa and 25Xb are connected to the first OIS driver 30X. The inner ends of the power supply wires 25Ya and 25Yb are connected to the substrate 22 and are connected to the driver IC 221Y via a booster unit 60, which will be described later. The outer ends of the power supply wires 25Ya and 25Yb are connected to the second OIS driver 30Y via the OIS biasing member 50 and power supply wires 18Ya and 18Yb. The inner ends of the power supply wires 25Za, 25Zb, 25Zc, and 25Zd are connected to the substrate 22 and are connected to the driver IC 221Z via a booster unit 60, which will be described later. The outer ends of the power supply wires 25Za, 25Zb, 25Zc, and 25Zd are connected to the two AF drive units 15 via the OIS biasing member 50 and the power supply wires 18Za, 18Zb, 18Zc, and 18Zd.

[0045] Here, as an example, driver IC 221X is a one-channel driver IC that controls the driving of one driver unit, and driver IC 221Y is also a one-channel driver IC. Driver IC 221Z is a two-channel driver IC that controls the driving of two driver units. The number of channels in driver ICs 221X, 221Y, and 221Z can be changed as appropriate depending on the number of driver units to be driven.

[0046] [substrate] The substrate 22 is disposed on the light-receiving side of the base 21 in the optical axis direction. The substrate 22 is electrically connected to terminals 23 exposed on the upper surface of the base 21, and the terminals 23 are connected to the driver ICs 221X, 221Y, 221Z, etc. via wiring (not shown) formed on the substrate 22. The driver ICs 221X, 221Y, 221Z are also connected to power supply wiring 25Xa, 25Xb, 25Ya, 25Yb, 25Za, 25Zb, 25Zc, and 25Zd via wiring (not shown) formed on the substrate 22. The power supply wiring 25Xa, 25Xb, 25Ya, 25Yb, 25Za, 25Zb, 25Zc, and 25Zd are connected to the first OIS driver 30X, the second OIS driver 30Y, and the AF driver 15, as described above.

[0047] The driver ICs 221X, 221Y, and 221Z are arranged on the light-receiving side of the substrate 22 in the optical axis direction, and each has a magnetic sensor (not shown). These magnetic sensors are configured, for example, with a Hall element or a TMR (Tunnel Magneto Resistance) sensor, and detect magnetic fields generated by magnets 17X, 17Y, and 17Z (magnets) (described later) to magnetically detect the position of the detection target in the X, Y, and Z directions.

[0048] On the substrate 22, the driver ICs 221X, 221Y, and 221Z are provided in an area where the AF driver 15, AF support units 16A and 16B, first OIS driver 30X, and second OIS driver 30Y are not provided (see FIG. 5). That is, they are provided in an area near one corner of the base 21, which is rectangular in plan view (see FIG. 9). This allows the driver ICs 221X, 221Y, and 221Z to be concentrated in one area, making it possible to effectively utilize the space within the optical element driver main body 4.

[0049] 11, a magnet 17X is disposed on the bottom side of the second stage 14, which moves in the X direction, and the driver IC 221X and the magnet 17X are disposed so as to face each other. The position of the second stage 14 in the X direction, i.e., the position of the OIS movable part 10 in the X direction, is detected by an X direction position detection unit consisting of the driver IC 221X and the magnet 17X.

[0050] 11, a magnet 17Y is disposed on the bottom side of the first stage 13, which moves in the Y direction, and the driver IC 221Y and the magnet 17Y are disposed so as to face each other. The Y-direction position detection unit consisting of the driver IC 221Y and the magnet 17Y detects the position of the first stage 13 in the Y direction, i.e., the position of the OIS movable part 10 in the Y direction.

[0051] 11, a magnet 17Z is disposed on the bottom side of the AF movable part 12 that moves in the Z direction, and the driver IC 221Z and the magnet 17Z are disposed opposite each other. The position of the AF movable part 12 in the Z direction is detected by a Z direction position detection part consisting of the driver IC 221Z and the magnet 17Z.

[0052] Note that instead of the combination of the magnets 17X, 17Y, and 17Z and the magnetic sensors of the driver ICs 221X, 221Y, and 221Z described above, position detection may be performed by other methods. For example, the positions of the OIS movable part 10 in the X and Y directions and the position of the AF movable part 12 in the Z direction may be detected by an optical sensor such as a photoreflector.

[0053] [Drive circuit] From the viewpoint of miniaturization, etc., the optical element driving device 1 uses ultrasonic motors including piezoelectric elements as the AF driving unit 15, the first OIS driving unit 30X, and the second OIS driving unit 30Y. Since a relatively large driving voltage is required to drive the ultrasonic motors, this embodiment includes a boosting unit 60 that boosts the input voltage to a desired voltage.

[0054] In this embodiment, the drive circuit is configured such that a booster unit 60 is connected between driver IC 221X and first OIS drive unit 30X, between driver IC 221Y and second OIS drive unit 30Y, and between driver IC 221Z and AF drive unit 15. Driver ICs 221X, 221Y, and 221Z are arranged on the top surface (light-receiving side in the optical axis direction) of substrate 22 (see FIG. 9), and booster unit 60 is arranged on the bottom surface (image-forming side in the optical axis direction) of substrate 22 (see FIG. 10).

[0055] The driver ICs 221X, 221Y, and 221Z each have a Hall element as a magnetic sensor, and output a drive current in response to the position of the magnets 17X, 17Y, and 17Z detected by the Hall element.

[0056] The booster 60 may be a series resonant circuit having an inductor, or a circuit in which a capacitor is connected in parallel to the series resonant circuit.

[0057] The drive currents output from the driver ICs 221X, 221Y, and 221Z are boosted by the boost unit 60 and supplied to the first OIS drive unit 30X, the second OIS drive unit 30Y, and the AF drive unit 15. This drives the first OIS drive unit 30X and the second OIS drive unit 30Y to perform shake correction, and drives the AF drive unit 15 to perform autofocus.

[0058] In this embodiment, the optical element driving device 1 has two AF driving units 15, a first OIS driving unit 30X, and a second OIS driving unit 30Y, and therefore has four sets of boosting units 60. The boosting units 60 are arranged at positions away from the magnets 17X, 17Y, and 17Z and the driver ICs 221X, 221Y, and 221Z. Although the inductors of the boosting units 60 have magnetic properties, the above-described arrangement can suppress the magnetic influence of the inductors of the boosting units 60 on the magnets 17X, 17Y, and 17Z and the driver ICs 221X, 221Y, and 221Z.

[0059] For example, in FIG. 10 , magnets 17X, 17Y, and 17Z are arranged on the light-receiving side of base 21 in the optical axis direction. Magnets 17X, 17Y, and 17Z are arranged at the lower left side of the figure. Booster unit 60 is arranged at a position away from magnets 17X, 17Y, and 17Z, or at least at a position that does not face magnets 17X, 17Y, and 17Z. This arrangement ensures a sufficient distance (in the X and Y directions) between the inductor of booster unit 60 and magnets 17X, 17Y, and 17Z, thereby suppressing magnetic influence from the inductor. As a result, the influence on the detectability of the magnetic sensor can be suppressed.

[0060] 10, the booster unit 60 is disposed on the bottom side of the substrate 22, which is the side that does not face the magnets 17X, 17Y, and 17Z. In this case, as shown in FIG. 10, an opening 219 is provided that penetrates the base 21, and when the substrate 22 is disposed on the upper surface of the base 21, the booster unit 60 provided on the bottom side of the substrate 22 is positioned within the opening 219. With this configuration, there is no need to ensure installation space for the booster unit 60 provided on the bottom side of the substrate 22, and the optical element driving device 1 can be made low-profile.

[0061] By arranging the booster unit 60 on the bottom side of the substrate 22, it is possible to ensure a sufficient distance (distance in the Z direction) between the inductor of the booster unit 60 and the magnets 17X, 17Y, and 17Z, thereby suppressing the magnetic influence from the inductor of the booster unit 60. As a result, it is possible to suppress the influence on the detectability of the magnetic sensor.

[0062] [OIS drive unit] The OIS driver 30 is an actuator that moves the OIS movable part 10 in the X and Y directions. Specifically, the OIS driver 30 has a first OIS driver 30X that moves the entire OIS movable part 10 in the X direction, and a second OIS driver 30Y that moves a part of the OIS movable part 10 (AF part 11) in the Y direction.

[0063] Although the first OIS driving section 30X and the second OIS driving section 30Y are arranged in different directions, they have the same components, and therefore the same reference numerals are used for the same components and they will be described with reference to FIG.

[0064] The first OIS driver 30X and the second OIS driver 30Y have ultrasonic motors that serve as drive sources for moving the OIS movable part 10. The first OIS driver 30X is fixed to an OIS motor fixing part 217 that is aligned in the X direction of the base 21. The second OIS driver 30Y is fixed to an OIS motor fixing part 134 that is aligned in the Y direction of the first stage 13. That is, the first OIS driver 30X and the second OIS driver 30Y are respectively arranged along the X-direction side surface 101X and the Y-direction side surface 101Y of the OIS movable part 10 that are perpendicular to each other (see FIGS. 3 to 5, etc.).

[0065] The first OIS driver 30X and the second OIS driver 30Y each have an OIS resonating unit 31 that is a resonating unit, an OIS piezoelectric element 32 that is a piezoelectric element, and an OIS power transmission unit 34 that is a power transmission unit. The driving force of the OIS driver 30 is transmitted to other components via the OIS power transmission unit 34. Specifically, the first OIS driver 30X is connected to the second stage 14 via the OIS power transmission unit 34, and the driving force is transmitted thereto. The second OIS driver 30Y is also connected to the second stage 14 via the OIS power transmission unit 34, and the driving force is transmitted thereto. In the OIS driver 30, the OIS resonating unit 31 constitutes an active element, and the OIS power transmission unit 34 constitutes a passive element.

[0066] The OIS resonator 31 is made of a conductive material, is sandwiched between the OIS piezoelectric element 32 (described later), and resonates with the vibration of the OIS piezoelectric element 32 to convert vibrational motion into linear motion. The OIS resonator 31 is formed by, for example, laser processing, etching, or pressing a metal plate.

[0067] The OIS resonance unit 31 of the first OIS driver 30X is fixed to the OIS motor fixing unit 217 (on the base 21 side) by, for example, rivets, adhesive, etc. The OIS resonance unit 31 of the second OIS driver 30Y is fixed to the OIS motor fixing unit 134 (on the first stage 13 side) by, for example, rivets, adhesive, etc.

[0068] The OIS piezoelectric element 32 is, for example, a plate-shaped element made of a ceramic material, and generates vibrations when a high-frequency voltage is applied to it. Two OIS piezoelectric elements 32 are bonded together and arranged so as to sandwich the OIS resonating unit 31.

[0069] The OIS piezoelectric element 32 of the first OIS drive section 30X is electrically connected to the above-mentioned power supply wiring 25Xa, 25Xb by, for example, an electrode member (not shown) etc. The OIS piezoelectric element 32 of the second OIS drive section 30Y is electrically connected to the above-mentioned power supply wiring 18Ya, 18Yb by, for example, an electrode member (not shown) etc. This connection makes it possible to apply a voltage to the OIS piezoelectric element 32, and applying a voltage causes the OIS piezoelectric element 32 to vibrate.

[0070] The OIS resonating unit 31 described above has at least two resonant frequencies and deforms in different ways for each resonant frequency. In other words, the OIS resonating unit 31 is configured to deform in different ways for each of the two resonant frequencies. The different ways are a way to advance the OIS power transmission unit 34 in the X direction or the Y direction, and a way to retreat the OIS power transmission unit 34. Therefore, by vibrating the OIS piezoelectric element 32 at a desired resonant frequency, the OIS power transmission unit 34 can be advanced or retreated in the X direction or the Y direction.

[0071] The OIS power transmission unit 34 is a chucking guide extending in the X or Y direction, one end of which abuts against the OIS resonating unit 31 to transmit the driving force from the OIS resonating unit 31. The other end of the OIS power transmission unit 34, a stage fixing unit 35, is connected to the second stage 14. Specifically, the stage fixing unit 35 of the first OIS driving unit 30X is fixed to an OIS chucking guide fixing unit 145X of the second stage 14. Furthermore, the stage fixing unit 35 of the second OIS driving unit 30Y is fixed to an OIS chucking guide fixing unit 145Y of the second stage 14.

[0072] In this way, the second OIS driver 30Y is fixed to the first stage 13 (on the OIS movable part 10 side) via the OIS motor fixing part 134, and is connected to the second stage 14 via the OIS power transmission part 34. The second OIS driver 30Y is driven during shake correction in the Y direction, and drives the first stage 13 to move in the Y direction relative to the second stage 14. Note that the second OIS driver 30Y moves together with the first stage 13 (OIS movable part 10) during shake correction in the X direction by the first OIS driver 30X.

[0073] Furthermore, the first OIS driver 30X is fixed to the base 21 (on the OIS fixing part 20 side) via an OIS motor fixing part 217, and is connected to the second stage 14 via an OIS power transmission part 34. The first OIS driver 30X is driven during shake correction in the X direction, and drives the second stage 14 to move in the X direction relative to the base 21 (OIS fixing part 20). Because the first OIS driver 30X moves the second stage 14 in the X direction relative to the base 21 (OIS fixing part 20), it is not affected by shake correction in the Y direction by the second OIS driver 30Y.

[0074] That is, movement by one OIS drive unit 30 is not hindered by the structure of the other OIS drive unit 30. Therefore, rotation of the OIS movable unit 10 around the Z axis can be prevented, and the OIS movable unit 10 can be swung with high precision within the XY plane.

[0075] [OIS support part] The OIS support section 40 supports the OIS movable section 10 relative to the OIS fixed section 20 so that the OIS movable section 10 can swing in a direction perpendicular to the optical axis while being spaced apart in the optical axis direction. In this embodiment, the OIS support section 40 has four X-direction reference balls 41 interposed between the OIS movable section 10 (second stage 14) and the base 21 (see FIG. 5). The OIS support section 40 also has four Y-direction reference balls 42 interposed between the first stage 13 and second stage 14 in the OIS movable section 10 (see FIG. 6).

[0076] In this embodiment, as described above, the four X-direction reference balls 41 are rollable in the X direction, but the rollable direction is restricted to the X direction. Furthermore, as will be described later, the four Y-direction reference balls 42 are rollable in the Y direction, but the rollable direction is restricted to the Y direction. By restricting the rollable directions of the X-direction reference balls 41 and the Y-direction reference balls 42 in this way, the OIS movable part 10 can be swung with high precision within the XY plane. Note that the number of X-direction reference balls 41 and Y-direction reference balls 42 constituting the OIS support part 40 can be changed as appropriate.

[0077] [OIS biasing member] An OIS biasing member 50 is disposed at each of the four corners (corner portions) of the rectangular OIS movable part 10 and OIS fixed part 20. The OIS biasing member 50 is formed, for example, by a tension coil spring, and connects the OIS movable part 10 and the OIS fixed part 20 together.

[0078] An end of the OIS biasing member 50 on the image-forming side in the optical axis direction is connected to the power supply wiring 25Ya, 25Yb, 25Za, 25Zb, 25Zc, and 25Zd exposed from a corner of the bottom surface of the base 21 (see FIG. 10). On the other hand, an end of the OIS biasing member 50 on the light-receiving side in the optical axis direction is connected to the power supply wiring 18Ya, 18Yb, 18Za, 18Zb, 18Zc, and 18Zd of the first stage 13 (see FIGS. 3 and 4).

[0079] The OIS biasing member 50 receives a tensile load when the OIS movable part 10 and the OIS fixed part 20 are connected, and acts to move the OIS movable part 10 and the OIS fixed part 20 closer to each other. That is, the OIS movable part 10 is held swingably within the XY plane while being biased by the OIS biasing member 50 toward the imaging side in the optical axis direction (while being pressed against the base 21). This makes it possible to hold the OIS movable part 10 in a stable state without rattle. Here, two OIS biasing members 50 are arranged radially outside the two AF drive parts 15, allowing the AF drive parts 15 to be driven in a stable state.

[0080] The OIS biasing member 50 is made of a conductive material and functions as a power supply line (conductive path) to the AF drive section 15 and the second OIS drive section 30Y.

[0081] Furthermore, the OIS biasing member 50 is disposed in notches (reference numerals omitted) formed by cutting out the four corners (corner portions) of the first stage 13 and the second stage 14 (see FIGS. 3 and 4). Because the notches are formed in the first stage 13 and the second stage 14, the OIS biasing member 50 can be disposed without increasing the size of the base 21, thereby suppressing an increase in the size of the device, that is, the optical element driving device 1 can be made more compact.

[0082] [OIS moving part] 11 is a bottom view of the OIS movable part 10. The OIS movable part 10 will be described with reference to FIG.

[0083] The OIS movable section 10 is configured to be able to hold the lens section 2 (see FIG. 2), and as shown in FIGS. 5 and 6, has an AF section 11, a second stage 14, etc. The AF section 11 also has an AF movable section 12, a first stage 13, an AF drive section 15, and AF support sections 16A and 16B, etc. The OIS movable section 10, in terms of its OIS function, is configured by stacking the first stage 13 and the second stage 14 on a base 21 of the OIS fixed section 20.

[0084] Furthermore, the OIS movable section 10 is configured to be movable together with the AF movable section 12 in a direction perpendicular to the optical axis by the OIS drive section 30 (first OIS drive section 30X and second OIS drive section 30Y). With respect to movement in the X direction, the entire OIS movable section 10, including the first stage 13 and second stage 14, is a movable body. On the other hand, with respect to movement in the Y direction, the second stage 14 functions as a fixed body together with the OIS fixed section 20, and only the AF section 11 (the AF movable section 12 and the first stage 13) functions as a movable body. Furthermore, the first stage 13 functions as an AF fixed section that supports the AF movable section 12.

[0085] [AF moving part] Fig. 8 is a plan view showing the positional relationship between the OIS fixed section 20 and the AF movable section 12. Fig. 13 is a bottom view of the AF movable section 12. The AF movable section 12 will be described with reference to Figs. 8 and 13. Note that Fig. 8 illustrates the OIS fixed section 20 and the AF movable section 12 in order to show the positional relationship between the OIS fixed section 20 and the AF movable section 12, but does not illustrate the first stage 13 and the second stage 14.

[0086] The AF movable unit 12 is a lens holder capable of holding the lens unit 2 (see FIG. 2), and is configured to be movable in the optical axis direction (Z direction) by the AF drive unit 15 while holding the lens unit 2. The AF movable unit 12 is moved in the optical axis direction, for example, when adjusting focus using the AF function. The AF movable unit 12 is disposed radially inward (toward the lens unit 2) and spaced apart from the first stage 13 (AF fixed unit), and is supported by the first stage 13 via AF support units 16A and 16B (see FIG. 5).

[0087] The AF movable portion 12 is formed of, for example, polyarylate (PAR), a PAR alloy in which a plurality of resin materials including PAR are mixed, a liquid crystal polymer, or the like.

[0088] The AF movable section 12 has a lens housing section 121 that has a cylindrical opening on the inside. The lens section 2 is fixed to an inner circumferential surface 121a of the lens housing section 121 by, for example, adhesive or the like (see FIG. 6).

[0089] The AF movable unit 12 has a protrusion 123 that protrudes radially outward from a portion of the outer circumferential surface 121b of the lens housing portion 121 and extends toward the image formation side in the optical axis direction. A magnet 17Z for Z position detection is provided inside the protrusion 123. As described above, the magnet 17Z is disposed in a position facing the driver IC 221Z (magnetic sensor) for Z position on the substrate 22 in the optical axis direction (see FIG. 8, etc.). The protrusion 123 is inserted into an insertion hole 132 of the first stage 13, which will be described later, and moves along the insertion hole 132 when the AF movable unit 12 moves in the Z direction.

[0090] Furthermore, first rail members 161 constituting the AF support units 16A and 16B are attached to the outer peripheral surface 121b of the lens housing unit 121. Here, as an example, the first rail members 161 are attached to three locations on the outer peripheral surface 121b of the lens housing unit 121. The AF movable unit 12 is supported by the AF support units 16A and 16B having the first rail members 161 etc. so as to be movable in the Z direction. The AF support units 16A and 16B having the first rail members 161 will be described later.

[0091] Furthermore, the lens housing portion 121 is connected to the AF drive portion 15 by an AF connection member (not shown). The AF movable portion 12 is driven by the AF drive portion 15 via the AF connection member connected to the lens housing portion 121, and moves in the Z direction.

[0092] [AF drive unit] The AF driving unit 15 is an actuator that moves the AF movable unit 12 in the Z direction. Similar to the OIS driving unit 30, the AF driving unit 15 has an ultrasonic motor that serves as a drive source for moving the AF movable unit 12.

[0093] Although the AF drive unit 15 differs in size, shape, etc., it basically has the same configuration as the OIS drive unit 30, and has an AF resonating unit that is a resonating unit, an AF piezoelectric element that is a piezoelectric element, and an AF power transmission unit that is a power transmission unit. Therefore, the components of the AF drive unit 15 will not be shown in the figures, and redundant explanations will also be omitted.

[0094] The AF drive unit 15 is fixed to the inner circumferential surface 131a of the opening 131 of the first stage 13 by, for example, rivets or adhesive. The drive force of the AF drive unit 15 fixed to the inner circumferential surface 131a is transmitted to the AF movable unit 12 via the AF power transmission unit and the AF connection member. In the AF drive unit 15 as well, the AF resonator constitutes the active element, and the AF power transmission unit constitutes the passive element.

[0095] In this embodiment, there is provided a pair of AF drive units 15. The arrangement of the AF drive units 15 will be described later with reference to Fig. 14, but the pair of AF drive units 15 are respectively arranged at diagonal positions of the OIS movable unit 10.

[0096] [Stage 1] 12 is a bottom view of the AF movable portion 12 and the first stage 13. The first stage 13 will be described with reference to FIG.

[0097] The first stage 13 supports the AF movable section 12 via AF support sections 16A and 16B. The second stage 14 is disposed on the imaging side of the first stage 13 in the optical axis direction via a Y-direction reference ball 42. The first stage 13 moves in the X and Y directions during shake correction, and the second stage 14 moves only in the X direction during shake correction.

[0098] The first stage 13 is a member having a substantially rectangular shape in a plan view seen from the optical axis direction, and is made of, for example, a liquid crystal polymer. The first stage 13 has a substantially circular opening 131 in a portion corresponding to the AF movable part 12. The first stage 13 has an insertion hole 132 formed therein that corresponds to the protrusion 123 of the AF movable part 12 (see FIG. 6).

[0099] The first stage 13 has, on its underside, a Y-direction reference ball holder 133 that holds the Y-direction reference ball 42 that constitutes the OIS support unit 40 (see FIG. 12). The Y-direction reference ball 42 is sandwiched between the Y-direction reference ball holder 133 and a Y-direction reference ball holder 143 of the second stage 14 that faces it in the Z direction (see FIG. 6).

[0100] The Y-direction reference ball holding portion 133 and the Y-direction reference ball holding portion 143 are recesses having rectangular openings extending in the Y direction. The Y-direction reference ball holding portion 133 and the Y-direction reference ball holding portion 143 are formed so that the groove width narrows toward the bottom surface of the recess, for example, so that the cross section has a substantially V-shape (tapered shape) or a substantially U-shape.

[0101] The groove formed by the recess having the above-described cross-sectional shape is formed parallel to the Y direction, so that the Y-direction reference ball 42 sandwiched between the Y-direction reference ball holding part 133 and the Y-direction reference ball holding part 143 can roll in the Y direction within the recess. That is, in the OIS movable part 10, the second stage 14 supports the first stage 13 via the Y-direction reference ball 42 so as to be movable in the Y direction.

[0102] The Y-direction reference ball holders 133 and 143 are arranged at the four corners of the rectangular first stage 13 and second stage 14, and the first stage 13 is supported by the second stage 14 at four points, i.e., by four Y-direction reference balls 42. In this way, the Y-direction reference balls 42 are held by multi-point contact and therefore roll stably in the Y direction.

[0103] The first stage 13 may be supported by the second stage 14 at at least three points. For example, when supported at three points, the Y-direction reference ball holders 133 and the Y-direction reference ball holders 143 may be disposed at a total of three locations: two locations on one side of the first stage 13 and the second stage 14 and one location on the side opposite that side.

[0104] In the first stage 13, the OIS motor fixing portion 134 on which the second OIS driving unit 30Y is disposed is recessed radially inward so that the second OIS driving unit 30Y can be disposed without protruding radially outward (see FIG. 6). Similarly, in the first stage 13, the recess 137 on which the first OIS driving unit 30X is disposed is also recessed radially inward.

[0105] In the first stage 13, AF motor fixing portions (numerals omitted) are provided on the inner surface 131a of the opening 131 at two locations that are point-symmetrical with respect to the center of the opening 131, and AF drive units 15 are respectively arranged and fixed to the two AF motor fixing portions.

[0106] Additionally, second rail members 164, 165 constituting AF support portions 16A, 16B are attached to inner circumferential surface 131a of opening 131. Here, as an example, second rail members 164, 165 are attached to three locations on inner circumferential surface 131a of opening 131. AF support portions 16A, 16B having second rail members 164, 165 will be described later.

[0107] Furthermore, a magnet 17Y for detecting the Y-position is disposed on the bottom surface of one of the frame portions of the first stage 13 along the X-direction (see FIG. 12). For example, the magnet 17Y is magnetized in the Y-direction. As described above, on the substrate 22, a driver IC 221Y having a magnetic sensor for detecting the Y-position is disposed at a position facing the magnet 17Y in the optical axis direction (see FIGS. 8, 9, etc.).

[0108] Furthermore, power supply wirings 18Ya, 18Yb, 18Za, 18Zb, 18Zc, and 18Zd are embedded in the first stage 13 by, for example, insert molding (see FIG. 6). The power supply wirings 18Ya, 18Yb, 18Za, 18Zb, 18Zc, and 18Zd are exposed from notches (reference numerals omitted) formed by cutting out the four corners of the first stage 13, and one end of the OIS biasing member 50 is connected to this portion.

[0109] The power supply wirings 18Ya and 18Yb are formed inside the first stage 13 so as to extend from the notches at the four corners to the vicinity of the second OIS driver 30Y to which power is to be supplied, and are connected to the second OIS driver 30Y. The power supply wirings 18Za and 18Zb are formed inside the first stage 13 so as to extend from the notches at the four corners to the vicinity of one of the AF drivers 15 to which power is to be supplied, and are connected to the AF driver 15. The power supply wirings 18Zc and 18Zd are formed inside the first stage 13 so as to extend from the notches at the four corners to the vicinity of another of the AF drivers 15 to which power is to be supplied, and are connected to the AF driver 15.

[0110] With the above configuration, power is supplied to the second OIS drive unit 30Y, which moves the first stage 13 in the Y direction, via power supply wiring 18Ya and 18Yb. Also, power is supplied to the AF drive unit 15, which moves the AF movable unit 12 in the Z direction, via power supply wiring 18Za, 18Zb, 18Zc, and 18Zd.

[0111] [Stage 2] The second stage 14 is a member having a substantially rectangular shape in a plan view seen from the optical axis direction, and is made of, for example, a liquid crystal polymer. The opening 141 of the second stage 14 is formed in a substantially rectangular shape (see FIG. 6). In the second stage 14, the recess 146 in which the second OIS driver 30Y is disposed is formed to be recessed radially inward, similar to the first stage 13. The notch 147 in which the first OIS driver 30X is disposed is formed integrally with the notched corner portion.

[0112] The second stage 14 has, on its upper surface, a Y-direction reference ball holding portion 143 that holds the Y-direction reference balls 42 that constitute the OIS support portion 40. The Y-direction reference ball holding portion 143 may have the same configuration as the above-described Y-direction reference ball holding portion 133 that is arranged opposite the Y-direction reference ball holding portion 143, and therefore a redundant description will be omitted here.

[0113] The second stage 14 also has, on its underside, an X-direction reference ball holder 144 that holds the X-direction reference ball 41 that constitutes the OIS support unit 40 (see FIG. 11). The X-direction reference ball holder 144 may have the same configuration as the above-described X-direction reference ball holder 218 that is arranged opposite the X-direction reference ball holder 144, and therefore a redundant description will be omitted here.

[0114] Furthermore, in the second stage 14, a magnet 17X for detecting the X position is disposed on the bottom surface of one of the frame portions along the Y direction (see FIG. 11). For example, the magnet 17X is magnetized in the X direction. As described above, on the substrate 22, a driver IC 221X having a magnetic sensor for detecting the X position is disposed at a position facing the magnet 17X in the optical axis direction (see FIGS. 8, 9, etc.).

[0115] As described above, in this embodiment, magnet 17X is arranged on second stage 14, which moves in the X direction, and magnet 17Y is arranged on first stage 13, which moves in the Y direction (see FIGS. 11 and 12). When moving only in the Y direction, first stage 13 moves but second stage 14 does not, and magnet 17X arranged on second stage 14 does not move either. Therefore, when position detection in the X direction is performed by magnet 17X, there is no influence from magnet 17Y, and detection accuracy can be improved.

[0116] [AF support part] As described above, the first rail member 161 is attached to the outer peripheral surface 121b of the lens housing portion 121 of the AF movable portion 12, and the second rail members 164, 165 are attached to the inner peripheral surface 131a of the opening 131 of the first stage 13 (see Figure 6).

[0117] The AF support part 16A is configured by sandwiching a Z-direction reference ball 162 held by a retainer 163 between a first rail member 161 and a second rail member 164. The AF support part 16B is configured by sandwiching a Z-direction reference ball 162 held by a retainer 163 between the first rail member 161 and a second rail member 165. That is, the AF support part 16A has the first rail member 161, the Z-direction reference ball 162, the retainer 163, and the second rail member 164. The AF support part 16B has the first rail member 161, the Z-direction reference ball 162, the retainer 163, and the second rail member 165.

[0118] The first rail member 161 has a clamping surface (reference numeral omitted) that rotatably clamps the Z-direction reference ball 162 when the first rail member 161 moves in the Z direction together with the AF movable unit 12, and a claw portion (reference numeral omitted) that is attached to the outer circumferential surface 121b of the lens housing portion 121. The clamping surface is a curved surface that extends in the optical axis direction, and is curved so that its central portion is recessed inward of the lens housing portion 121 in plan view. The claw portions extend toward the inside of the lens housing portion 121 and are arranged at two locations that sandwich the clamping surface.

[0119] Insertion grooves (reference numerals omitted) into which the claws are inserted are formed on the outer peripheral surface 121b of the lens housing portion 121. The first rail member 161 is attached to the outer peripheral surface 121b of the lens housing portion 121 by inserting the claws into the insertion grooves and fixing them.

[0120] The second rail member 164 also has a clamping surface (reference numeral omitted) that rotatably clamps the Z-direction reference ball 162. The clamping surface is a curved surface that extends in the optical axis direction, and in plan view, its central portion is curved so as to be recessed outward relative to the outer circumferential surface 121b of the lens housing portion 121.

[0121] The second rail member 164 is disposed in a groove (reference numeral omitted) formed in the inner circumferential surface 131a of the opening 131, and is fixed to the groove by a joining method such as adhesive.

[0122] The second rail member 165 has a fixed portion (symbol omitted) that is fixed to a recess (symbol omitted) formed on the inner surface 131a of the opening 131, and an applying portion (symbol omitted) that contacts the Z-direction reference ball 162 to apply a biasing force.

[0123] The inside of the application portion (the first rail member 161 side) is a clamping surface (reference numeral omitted) that rotatably clamps the Z-direction reference ball 162. The clamping surface is a curved surface extending in the optical axis direction, and its central portion is curved so as to be recessed outward relative to the outer circumferential surface 121b of the lens housing portion 121 in plan view.

[0124] The application portion is connected to two deformation portions arranged on either side of the application portion. In plan view, the deformation portion is formed in a serpentine shape, and the two deformation portions are arranged so as to be line-symmetrical with the application portion in between. The deformation portion thus formed is elastically deformable, and transmits the restoring force generated by the elastic deformation to the application portion as a biasing force. In other words, the second rail member 165 functions as an elastic member.

[0125] When three support parts are provided, if two AF support parts 16A and one AF support part 16B are combined, only one AF support part 16B, which requires space, is provided, thereby saving space and enabling the overall device to be made smaller. Also, since only one second rail member 165 with a complex shape is required, costs can be reduced compared to when multiple second rail members are provided.

[0126] As an example, the retainer 163 holds two Z-direction reference balls 162. The two Z-direction reference balls 162 are arranged in line along the optical axis direction by the retainer 163, and are positioned in the optical axis direction while being held so that a constant distance between them is maintained. The retainer 163 may have three or more Z-direction reference balls 162 (balls), but when the retainer 163 has two balls, the diameter of the balls can be made larger and the rolling resistance of the balls can be made smaller than when the retainer has three or more balls.

[0127] Here, as an example, two AF support parts 16A and one AF support part 16B are arranged, and the AF movable part 12 is supported by the AF support parts 16A and 16B so as to be movable in the Z direction relative to the first stage 13. The AF support parts 16A and 16B are arranged on the inner circumferential surface 131a of the opening 131 of the first stage 13 at positions dispersed at least at three locations in the circumferential direction.

[0128] When the AF support portions 16A, 16B are arranged in three separate locations, it is desirable that the angles between the AF support portions 16A, 16B be 120° apart, but this angle can be changed as appropriate.

[0129] Furthermore, the AF support portions 16A and 16B may be arranged in four or more locations on the inner peripheral surface 131a of the opening 131, but it is desirable to arrange them in locations that are a multiple of three, such as six or nine locations, so as to provide further support between the three support points, based on a three-point support that can stably support the object.

[0130] In the AF supports 16A and 16B, the Z-direction reference ball 162 is configured to be pressed and urged toward the first rail member 161 by the second rail members 164 and 165. That is, the Z-direction reference ball 162 is configured to come into contact with the first rail member 161 and be pressed and urged in a direction toward the inside of the opening 131. At this time, as shown in FIG. 14 described later, the directions of pressing forces F1 to F3 with which the Z-direction reference ball 162 presses the first rail member 161 are preferably directions toward a point located inside the opening 131 when viewed from the optical axis direction (see the dashed-dotted line and the dashed-two-dotted line). For example, the directions of the pressing forces F1 to F3 are preferably directions toward the center of the opening 131 (the position of the optical axis OA).

[0131] On the inner circumferential surface 131a of the opening 131, the AF support portions 16A and 16B and the AF drive portion 15 are arranged at different locations. Here, as an example, a total of three AF ​​support portions 16A and 16B and a total of two AF drive portions 15 are arranged. More specifically, one AF drive portion 15 is arranged between one AF support portion 16A and the AF support portion 16B, and the other AF drive portion 15 is arranged between the other AF support portion 16A and the AF support portion 16B. In this case, the AF drive portions 15 are arranged on the inner circumferential surface 131a of the opening 131, dispersed in the circumferential direction, similar to the AF support portions 16A and 16B. Here, the AF drive portions 15 are arranged at two locations different from the locations where the AF support portions 16A and 16B are arranged, and are point-symmetrical with respect to the center of the opening 131.

[0132] The AF support portions 16A and 16B are disposed at at least three locations on the inner circumferential surface 131a of the opening 131, so that the first stage 13 can stably support the AF movable portion 12 via the AF support portions 16A and 16B. In addition, the Z-direction reference balls 162 of the AF support portions 16A and 16B are configured to abut against the first rail member 161 and press and urge the AF movable portion 12 in a direction toward the inside of the lens housing portion 121. Therefore, the AF movable portion 12 is supported so as to be movable in the optical axis direction while being pressed and urged in a direction toward the inside of the lens housing portion 121, and tilt of the lens unit 2 can be suppressed. As a result, the first stage 13 can stably and movably support the AF movable portion 12 and the lens unit 2 via the AF support portions 16A and 16B.

[0133] Although the AF support units 16A and 16B are configured to use the Z-direction reference ball 162, roller members may be used instead of the Z-direction reference ball 162. In this case, the shapes of the first rail member 161 and the second rail members 164 and 165 may be changed depending on the shape and arrangement of the roller members. Furthermore, instead of the Z-direction reference ball 162 and the retainer 163, a shaft member extending in the optical axis direction, a protruding portion protruding outward from the outer circumferential surface 121b of the lens housing unit 121, or a protruding portion protruding inward from the inner circumferential surface 131a of the opening 131 may be used. In this case, the shapes of the first rail member 161 and the second rail members 164 and 165 may be changed so that the shaft member or the protruding portion is supported so as to be slidable in the optical axis direction.

[0134] [Layout of AF drive unit, AF support unit, and OIS drive unit] Here, the arrangement of the AF drive unit 15, AF support units 16A and 16B, and OIS drive unit 30 (first OIS drive unit 30X and second OIS drive unit 30Y) will be described with reference to Fig. 14. Fig. 14 is a plan view that schematically shows the optical element drive device main body 4. Fig. 14 schematically shows the arrangement of the AF drive unit 15, AF support units 16A and 16B, first OIS drive unit 30X, and second OIS drive unit 30Y, as well as related configurations, to show the relative positions of these units.

[0135] As described above, the optical element driving device main body 4 has the first OIS driving unit 30X and the second OIS driving unit 30Y. When having such a configuration, the first OIS driving unit 30X and the second OIS driving unit 30Y are arranged in the OIS movable unit 10 as described below.

[0136] Specifically, the first OIS driver 30X and the second OIS driver 30Y are arranged along two side surfaces, an X-direction side surface 101X and a Y-direction side surface 101Y, of the OIS movable part 10. As shown in Fig. 14, the X-direction side surface 101X is a side surface that extends from corner CO1 (first corner in the present invention) toward corner CO2 (second corner in the present invention) of the four corners CO1 to CO4 of the OIS movable part 10. The Y-direction side surface 101Y is a side surface that extends from corner CO1 toward corner CO3 (third corner in the present invention) of the OIS movable part 10.

[0137] As described above, the optical element driving device main body 4 has two AF driving units 15, two AF support units 16A, and one AF support unit 16B. When having such a configuration, the AF driving unit 15 and the AF support units 16A and 16B are arranged on the first stage 13 (inner peripheral surface 131a) as described below.

[0138] Specifically, one AF support part 16B having a second rail member 165 is disposed on the first stage 13 in a portion corresponding to one of the four corners CO1 to CO4, namely, corner CO1. The other two AF support parts 16A are disposed in portions avoiding the four corners CO1 to CO4. A pair of AF drive parts 15 are then disposed in portions corresponding to corners CO2 and CO3, located on both sides of the corner CO1, at diagonal positions facing each other across the optical axis OA. In this manner, the pair of AF drive parts 15 are disposed in portions different from the portions where the AF support parts 16A and 16B are disposed.

[0139] In this embodiment, one AF support portion 16B is a portion that applies a biasing force by the second rail member 165, and two AF support portions 16A are portions that receive the biasing force. In this configuration, the position of the AF support portion 16A on the inner circumferential surface 131a of the opening 131 of the first stage 13 is set and arranged as follows.

[0140] Specifically, in the AF support part 16B, the direction (pressing direction) of the pressing force F1 on the Z-direction reference ball 162 due to the biasing force of the second rail member 165 is assumed, for example, an extension line (two-dot chain line in FIG. 7) extending the direction of the pressing force F1. The positions of the two AF support parts 16A are set and arranged so that they are line-symmetrical with respect to the assumed extension line. By arranging the two AF support parts 16A in such positions, the biasing force that the two AF support parts 16A receive from the one AF support part 16B becomes equal, and the AF movable part 12 can be stably supported.

[0141] The ideal interval between the two AF support parts 16A and one AF support part 16B is 120°. However, this interval does not necessarily have to be 120°. In that case, as described above, the AF support parts 16A may be positioned and arranged so as to be line-symmetrical with respect to the direction (extension) of the pressing force F1. Furthermore, the pair of AF drive parts 15 are also arranged so as to face each other at the portions corresponding to the corners CO2 and CO3 so as to be line-symmetrical with respect to the direction (extension) of the pressing force F1.

[0142] Furthermore, driver ICs 221X, 221Y, and 221Z each having a magnetic sensor are disposed on the substrate 22 attached to the base 21 at a portion corresponding to a corner CO4 (fourth corner in the present invention) opposite the corner CO1.

[0143] As described above, the AF driver 15, AF support 16B, and driver ICs 221X, 221Y, and 221Z, which require space, are arranged in areas corresponding to the four corners CO1 to CO4. Furthermore, the AF support 16A, which requires less space than the AF support 16B, is arranged in an area that avoids the corners CO1 to CO4. In other words, the AF driver 15, AF support 16A, AF support 16B, and driver ICs 221X, 221Y, and 221Z are arranged by effectively utilizing the space within the optical element driver 1. This allows a pair of AF drivers 15 to be arranged within the optical element driver 1, and also allows the optical element driver 1 to be made more compact.

[0144] [Operation of optical element driving device] In the optical element driving device 1, when a voltage is applied to the AF driving unit 15, the AF piezoelectric element vibrates, causing the AF resonating unit to resonate and deform in a manner corresponding to the frequency. The deformation of the AF resonating unit causes the AF power transmission unit to move in the Z direction. Accordingly, the AF movable unit 12 moves in the Z direction, and focusing is performed. Because the AF support units 16A and 16B have balls (Z-direction reference balls 162), the AF movable unit 12 can move smoothly in the Z direction. Furthermore, in the AF driving unit 15, the AF power transmission unit abuts against the AF resonating unit in an energized state. Therefore, simply by lengthening the abutting portion in the Z direction, the movement stroke of the AF movable unit 12 can be easily lengthened without compromising the low profile of the optical element driving device 1.

[0145] Furthermore, in the optical element driving device 1, when a voltage is applied to the OIS driving section 30, the OIS piezoelectric element 32 vibrates, causing the OIS resonating section 31 to resonate and deform in a manner that corresponds to the frequency. The deformation of the OIS resonating section 31 causes the OIS power transmission section 34 to move in the X and Y directions. Accordingly, the OIS movable section 10 moves in the X and Y directions, and shake correction is performed. Because the OIS support section 40 has balls (X-direction reference ball 41 and Y-direction reference ball 42), the OIS movable section 10 can move smoothly in the X and Y directions.

[0146] Specifically, when the second OIS drive unit 30Y is driven and its OIS power transmission unit 34 moves in the Y direction, power is transmitted from the first stage 13, on which the second OIS drive unit 30Y is disposed, to the second stage 14. At this time, the X-direction reference ball 41 sandwiched between the second stage 14 and the base 21 cannot roll in the Y direction, so the position of the second stage 14 in the Y direction relative to the base 21 is maintained. On the other hand, the Y-direction reference ball 42 sandwiched between the first stage 13 and the second stage 14 can roll in the Y direction, so the first stage 13 moves in the Y direction relative to the second stage 14. In other words, the base 21 and the second stage 14 serve as fixed bodies for the OIS function, and the AF unit 11 (the AF movable unit 12 and the first stage 13) serves as a movable body for the OIS function.

[0147] Furthermore, when the first OIS drive unit 30X is driven and its OIS power transmission unit 34 moves in the X direction, power is transmitted from the base 21, on which the first OIS drive unit 30X is disposed, to the second stage 14. At this time, the Y-direction reference ball 42 sandwiched between the first stage 13 and the second stage 14 cannot roll in the X direction, so the position of the first stage 13 in the X direction relative to the second stage is maintained. On the other hand, the X-direction reference ball 41 sandwiched between the second stage 14 and the base 21 can roll in the X direction, so the second stage 14 moves in the X direction relative to the base 21. The first stage 13 also moves in the X direction following the second stage 14. In other words, the base 21 serves as a fixed body for the OIS function, and the AF unit 11 (the AF movable unit 12 and the first stage 13) and the second stage 14 serve as movable bodies for the OIS function.

[0148] In this way, the OIS movable part 10 swings within the XY plane, and shake correction is performed. Specifically, the voltages applied to the first OIS drive part 30X and the second OIS drive part 30Y are controlled based on a detection signal indicating angular shake from a shake detection part (for example, a gyro sensor) so that the angular shake of the camera module A is offset. At this time, the translational movement of the OIS movable part 10 can be accurately controlled by feeding back the detection results of the X and Y position detection part, which is composed of the magnets 17X and 17Y and the magnetic sensors of the driver ICs 221X and 221Y.

[0149] [effect] As described above, in the optical element driving device 1 of this embodiment, the pair of AF driving units 15 are arranged to face each other. This makes it possible to increase the thrust force that drives the first stage 13 that holds the lens unit 2, making it possible to speed up the responsiveness of the AF operation, and also making it possible to perform the AF operation even if the weight of the lens unit 2 increases.

[0150] Furthermore, in the optical element driving device 1 of this embodiment, as described above, one AF support part 16B that applies a biasing force to the AF movable part 12 is disposed in a portion corresponding to one corner CO1 of the first stage 13. Then, a pair of AF driving parts 15 are disposed facing each other in portions corresponding to corners CO2 and CO3 located on both sides of corner CO1. In this way, the AF support part 16B and the AF driving part 15, which require space, are disposed in portions corresponding to corners CO1 to CO3 of the first stage 13, so that the space within the optical element driving device 1 can be effectively utilized, and the optical element driving device 1 can be made smaller.

[0151] Furthermore, in the optical element driving device 1 of this embodiment, as described above, the driver ICs 221X, 221Y, and 221Z, each having a magnetic sensor, are arranged in a portion of the substrate 22 that corresponds to the corner CO4 opposite the corner CO1. In this way, the driver ICs 221X, 221Y, and 221Z, which require space, are arranged in the portion that corresponds to the corner CO4, so that the space within the optical element driving device 1 can be effectively utilized, and the optical element driving device 1 can be made smaller.

[0152] Furthermore, in the optical element driving device 1 of this embodiment, two AF support members 16A and one AF support member 16B are disposed at three circumferential locations on the inner circumferential surface 131a of the opening 131 of the first stage 13. Furthermore, a pair of AF drivers 15 are disposed at locations on the inner circumferential surface 131a that are different from the locations where the AF support members 16A and 16B are disposed and that face each other. This distributes the locations where force is applied to the AF movable member 12 around the circumferential surface 131a, making the AF movable member 12 less likely to deform and also suppressing localized deformation. Because the AF movable member 12 is less likely to deform, the two AF support members 16A, one AF support member 16B, and the pair of AF drivers 15 allow the AF movable member 12 to move smoothly in the optical axis direction.

[0153] In the optical element driving device 1 of this embodiment, the two AF support parts 16A are arranged to be line-symmetrical with respect to the direction (extension) of the pressing force F1 of the AF support part 16B. The pair of AF drive parts 15 are also arranged to be line-symmetrical with respect to the direction (extension) of the pressing force F1, facing each other at portions corresponding to the corners CO2 and CO3. With this arrangement, the two AF support parts 16A press the AF movable part 12 line-symmetrically with respect to the extension line of the pressing force F1, and the pair of AF drive parts 15 apply driving force to the AF movable part 12 from line-symmetric positions. This allows for well-balanced pressing, allowing the AF movable part 12 to move smoothly in the optical axis direction. Even if the AF movable part 12 elastically deforms due to the pressing of the two AF support parts 16A, the AF movable part 12 elastically deforms line-symmetrically, allowing for well-balanced pressing, allowing the AF movable part 12 to move smoothly in the optical axis direction.

[0154] Furthermore, according to the optical element driving device 1 of this embodiment, the AF driving unit 15, together with the OIS driving unit 30, is configured with an ultrasonic motor, so that the influence of external magnetism can be reduced, and the above-mentioned configuration allows for miniaturization and a low profile.

[0155] Furthermore, even if camera modules A having optical element driving devices 1 are arranged close to each other as in the smartphone M shown in FIG. 1B, there is no magnetic influence, making it extremely suitable for dual cameras.

[0156] Furthermore, since the AF movable section 12 is supported by the above-described AF support sections 16A and 16B, the movement of the AF movable section 12 is stable, and the driving performance of the optical element driving device 1 is significantly improved.

[0157] [Other embodiments] The present invention is not limited to the above-described embodiment, and can be modified within the scope of the present invention.

[0158] For example, in the above embodiment, the AF support section for three-point support of the AF movable section 12 is configured by combining two AF support sections 16A and one AF support section 16B, but it may be configured with three AF ​​support sections 16A or three AF ​​support sections 16B. In such a configuration, the AF drive section 15 and the AF support section 16A, or the AF drive section 15 and the AF support section 16B, are arranged in the same manner as in the arrangement described with reference to FIG.

[0159] For example, in the case of two AF drive units 15 and three AF ​​support units 16A, they are arranged as follows: Specifically, one AF support unit 16A is arranged in a portion corresponding to one corner CO1 (first corner in the present invention) of the four corners CO1 to CO4 of the first stage 13, and the other AF support unit 16A is arranged in a portion avoiding the four corners CO1 to CO4. Then, a pair of AF drive units 15 are arranged in portions corresponding to corners CO2 and CO3 (second and third corners in the present invention) located on both sides of the corner CO1, facing each other across the optical axis OA.

[0160] Furthermore, in the case of two AF drive units 15 and three AF ​​support units 16B, they are arranged as follows: Specifically, one AF support unit 16B is arranged in a portion corresponding to one corner CO1 (first corner in the present invention) of the four corners CO1 to CO4 of the first stage 13, and the other AF support unit 16B is arranged in a portion avoiding the four corners CO1 to CO4. Then, a pair of AF drive units 15 are arranged in portions corresponding to corners CO2 and CO3 (second and third corners in the present invention) located on both sides of the corner CO1, facing each other across the optical axis OA.

[0161] Furthermore, while the above embodiment has been described using a smartphone M as an example, the present invention can be applied to camera-equipped devices having a camera module and an image processing unit that processes image information obtained by the camera module. Camera-equipped devices include information devices and transportation equipment. Information devices include, for example, camera-equipped mobile phones, notebook computers, tablet terminals, portable game consoles, web cameras, and camera-equipped in-vehicle devices (for example, backup monitor devices and drive recorder devices). Furthermore, transportation equipment includes, for example, automobiles.

[0162] 15A and 15B are diagrams showing an automobile V as a camera-mounted device equipped with an in-vehicle camera module VC (Vehicle Camera). FIG. 15A is a front view of the automobile V, and FIG. 15B is a rear perspective view of the automobile V. The automobile V is equipped with the camera module A described in the above embodiment as the in-vehicle camera module VC. As shown in FIGS. 15A and 15B, the in-vehicle camera module VC is attached, for example, to the windshield facing forward or to the rear gate facing backward. This in-vehicle camera module VC is used for backup monitoring, drive recorders, collision avoidance control, autonomous driving control, etc.

[0163] In the above embodiment, the optical element driving device 1 is described as driving the lens unit 2 as an optical element, but the optical element to be driven may be an optical element other than a lens, such as a mirror or a prism. In addition, the optical element driving device 1 can be applied not only to autofocusing but also to zooming and other cases where the AF movable unit 12 is moved in the optical axis direction.

[0164] The above describes embodiments and modifications of the present invention. Note that the above description is an example of a preferred embodiment of the present invention, and the scope of the present invention is not limited to this. In other words, the description of the configuration of the above device and the shape of each part is one example, and it is clear that various modifications and additions to these examples are possible within the scope of the present invention. [Industrial Applicability]

[0165] The optical element driving device and camera module according to the present invention are useful when installed in camera-equipped devices such as smartphones, mobile phones, digital cameras, notebook computers, tablet terminals, portable game consoles, and vehicle-mounted cameras. [Explanation of symbols]

[0166] 1 Optical element driving device 2 Lens section 3 Cover 4 Optical element driving device main body 5. Imaging unit 10 OIS moving part (an example of the second moving part) 11 AF section 12 AF moving part (example of the first moving part) 13 First Stage 14 Second Stage 15 AF drive unit (an example of the first drive unit) 16A, 16B AF support part 17X, 17Y, 17Z magnets 18Ya, 18Yb, 18Za, 18Zb, 18Zc, 18Zd Power supply wiring 20 OIS fixing part 21 Base 22 PCB 23 terminals 25Xa, 25Xb power supply wiring 25Ya, 25Yb, 25Za, 25Zb, 25Zc, 25Zd Power supply wiring 30 OIS drive unit (an example of the second drive unit) 30X 1st OIS drive unit 30Y 2nd OIS drive unit 31 OIS resonator 32 OIS piezoelectric element 34 OIS power transmission section 35 Stage fixing part 40 OIS support part 41 X-direction reference ball 42 Y-direction reference ball 50 OIS biasing member 60 Booster section 101X X direction side 101Y Y direction side 121 Lens housing 121a, 131a Inner surface 121b Outer surface 123 Protrusion 131, 141, 211, 301, 401 opening 132 Insertion hole 133 Y-direction reference ball holder 134 OIS motor fixing part 137 Recess 143 Y-direction reference ball holder 144 X-direction reference ball holder 145X, 145Y OIS chucking guide fixing part 147 Notch 161 First rail member 162 Z-direction reference ball 163 Retainer 164, 165 Second rail member 217 OIS motor fixing part 218 X-direction reference ball holder 219 Opening 501 Image sensor board 502 Image sensor 503 Control Unit CO1, CO2, CO3, CO4 corner

Claims

1. a first movable section configured to be movable in the optical axis direction by a first driving section while holding the optical element; a fixed portion having an opening in which the first movable portion is disposed and having a rectangular shape in a plan view from the optical axis direction; support portions disposed at at least three circumferentially dispersed positions inside the opening, the support portions supporting the first movable portion movably in the optical axis direction; Equipped with one of the support portions has an elastic member that presses the first movable portion toward the inside of the opening, and is disposed at a portion corresponding to a first corner portion of four corner portions of the fixed portion; the other support portions are arranged in portions avoiding the four corner portions, the first drive units are respectively disposed at diagonal positions corresponding to second and third corners of the four corners, the second and third corners being positioned on either side of the first corner, and are arranged line-symmetrically with respect to the pressing direction of the elastic member; Optical element driver.

2. the other support portions arranged in portions avoiding the four corner portions are arranged line-symmetrically with respect to the pressing direction of the elastic member, The first driving portions are respectively disposed between the support portion disposed in the portion corresponding to the first corner portion and other support portions positioned on both sides of the support portion in the circumferential direction, The optical element driving device according to claim 1 .

3. a second movable portion configured to be movable together with the first movable portion and the fixed portion in a direction perpendicular to the optical axis by a second driving portion on the base; the second drive portion is disposed along each of two side surfaces extending from the first corner portion toward the second corner portion and the third corner portion, respectively; 3. The optical element driving device according to claim 1.

4. a position detection unit disposed in a portion of the base corresponding to a fourth corner portion opposite the first corner portion, the position detection unit detecting positions of the first movable portion and the second movable portion, The optical element driving device according to claim 3 .

5. The optical element driving device according to any one of claims 1 to 4, an imaging unit that captures a subject image formed by the optical element; Equipped with Camera module.

6. A camera-equipped device that is an information device or a transportation device, The camera module according to claim 5; an image processing unit that processes image information obtained by the camera module; Equipped with Camera-equipped device.

Images