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

Abstract

To smoothly move a member for holding a lens.SOLUTION: An optical element drive device comprises: a holding part capable of holding an optical element; a fixing part movably supporting the holding part via a bearing member; a drive part having a first magnet arranged on one of the holding part and the fixing part and a first coil arranged on the other, and moving the holding part; a first yoke arranged on the other side opposite the first magnet and biasing the holding part against the bearing member; and an adjustment part having a second magnet arranged on one of the holding part and the fixing part and a second coil arranged on the other, and adjusting biasing force for biasing the holding part against the bearing member.SELECTED DRAWING: Figure 3

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 installed in a camera-equipped device such as a smartphone or a drone. Such a camera module uses an optical element driving device that drives an optical element. A drone is an unmanned aerial vehicle that can be flown by remote control or automatic control, and some drones are called multicopters.

[0003] The optical element driving device has an autofocus function (hereinafter referred to as an "AF function": AF: Auto Focus), etc. The optical element driving device uses the AF function to automatically adjust the focus when photographing a subject.

[0004] As an example of an optical element driving device having such an AF function, Patent Document 1 discloses a lens driving device that houses a lens barrel having a lens in a housing and is equipped with a driving unit that drives the lens barrel in the optical axis direction. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2011-197626 A Summary of the Invention [Problem to be solved by the invention]

[0006] In the lens driving device shown in Patent Document 1, a guide ball (support member) that supports the lens barrel so that it can move in the optical axis direction is disposed between the housing and the lens barrel. The guide ball is held between the housing and the lens barrel by magnetic force between a magnet that constitutes a driving unit fixed to the lens barrel and a yoke fixed to the housing.

[0007] In recent years, in order to improve the image quality of camera modules, the image sensors have tended to become larger in diameter, which has led to a trend toward larger lens sizes. As the lens size becomes larger, the driving force for driving the lens barrel needs to be increased, which in turn requires that the magnetic force of the magnet itself used to drive the lens barrel be increased.

[0008] As the magnetic force of the magnet itself increases, the magnetic force between the magnet and the yoke also increases, which increases the force biasing the housing and lens barrel against the guide ball, and the friction with the guide ball increases, which may impede the movement of the lens barrel.

[0009] An object of the present invention is to provide an optical element driving device, a camera module, and a camera-mounted device that are capable of smoothly moving a member that holds a lens. [Means for solving the problem]

[0010] The optical element driving device according to the present invention comprises: A holder capable of holding an optical element; a fixing portion that movably supports the holding portion via a support member; a drive unit that has a first magnet disposed on one of the holding unit and the fixed unit, and a first coil disposed on the other, and that moves the holding unit; a first yoke disposed on the other side facing the first magnet and biasing the holding portion against the support member; an adjustment unit including a second magnet disposed on one of the holding unit and the fixed unit, and a second coil disposed on the other, the adjustment unit adjusting a biasing force that biases the holding unit against the support member; Equipped with.

[0011] The camera module according to the present invention comprises: The optical element driving device; an imaging unit that captures an object image using the optical element; Equipped with.

[0012] The camera-mounted device according to the present invention comprises: A camera-equipped device that is an information device or a transport device, The camera module; an image processing unit that processes image information obtained by the camera module; Equipped with. Effect of the Invention

[0013] According to the present invention, the member that holds the lens can be moved smoothly. [Brief description of the drawings]

[0014] [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. [Diagram 2] FIG. 2 is a perspective view showing a camera module and an imaging unit. [Diagram 3] 3 is a plan view of an optical element driving device main body of the optical element driving device of the camera module shown in FIG. 2. [Figure 4] 4 is a perspective view showing a holding portion of the optical element driving device main body shown in FIG. 3. [Diagram 5] 4 is a perspective view showing a housing section of the optical element driving device main body shown in FIG. 3 with a substrate section removed. FIG. [Figure 6]4 is a perspective view showing a housing section of the optical element driving device main body shown in FIG. 3 with a substrate section attached. FIG. [Figure 7A] 1 is a front view showing an automobile as a camera-mounted device equipped with an in-vehicle camera module. [Figure 7B] FIG. 7B is a perspective view of the automobile shown in FIG. 7A as seen obliquely from the rear side. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

[0016] [Smartphone] 1A and 1B are diagrams showing a smartphone M (an example of a camera-mounted 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.

[0017] The smartphone M has a dual camera consisting of two rear cameras OC1 and OC2. In this embodiment, the camera module A is applied to the rear cameras OC1 and OC2.

[0018] The camera module A has an AF function and can automatically adjust the focus when photographing a subject. The camera module A may also have an image stabilization function (hereinafter referred to as the "OIS function"; OIS: Optical Image Stabilization). The OIS function optically corrects shake (vibration) that occurs during shooting, making it possible to take images without blurring.

[0019] [Camera module] Fig. 2 is a perspective view showing the camera module A and the imaging unit 5. Fig. 3 is a plan view of an optical element driving device main body 4 of the optical element driving device 1 of the camera module A shown in Fig. 2. As shown in Figs. 2 and 3, in this embodiment, an orthogonal coordinate system (X, Y, Z) is used for explanation. Also, in the drawings described later, an orthogonal coordinate system (X, Y, Z) is used for explanation.

[0020] For example, when a photograph is taken with a smartphone M, 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 of the optical axis OA of the lens unit 2 shown in FIG. 2, and in FIG. 2, 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. In addition, hereinafter, the X direction and the Y direction perpendicular to the Z axis are referred to as the "optical axis perpendicular direction", and the XY plane is referred to as the "optical axis perpendicular plane". In addition, the direction perpendicular to the optical axis is referred to as the "radial direction".

[0021] In the following description, the optical axis OA is used, but the optical axis direction of the optical axis OA may be referred to as the optical path direction or the focal direction (the direction for adjusting the focal point) depending on the type of optical element. Here, the optical path is the path of light formed by the opening 301 of the cover 3, the opening 11 of the holding part 10, or the housing opening 21 of the housing part 20, and the direction in which this optical path extends (the penetrating direction of each opening) is the optical path direction.

[0022] 2, the camera module A includes an optical element driving device 1 that realizes an AF function, a lens unit 2 formed 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.

[0023] [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 approximately rectangular in plan view from the Z direction. In this embodiment, the cover 3 has an approximately square shape in plan view. The cover 3 has an approximately circular opening 301 on the upper surface. The lens unit 2 is accommodated in the opening 11 of the holding part 10 of the optical element driving device main body 4, faces the outside from the opening 301 of the cover 3, and is configured to protrude toward the light receiving side beyond the opening surface of the cover 3 as it moves in the Z direction. The inner wall of the cover 3 is fixed to the accommodation part 20 of the optical element driving device main body 4 by, for example, adhesion or the like, and accommodates the optical element driving device main body 4.

[0024] The cover 3 has a member for blocking electromagnetic waves from the outside of the optical element driving device 1 and from the inside of the cover 3, for example a shielding member made of a magnetic material.

[0025] [Imaging unit] The imaging unit 5 is disposed on the imaging side 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 an image of a subject formed by the lens unit 2.

[0026] The control unit 503 is formed of, 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 in the image sensor substrate 501, or in a camera-mounted device (in this embodiment, a smartphone M) on which the camera module A is mounted.

[0027] 2, the lens unit 2 is driven in the Z direction by the optical element driving device 1 with respect to the image sensor board 501 whose position is fixed, thereby forming an image of the subject on the imaging element 502, but for example, the imaging element 502 may be driven in the Z direction. In this case, the lens unit 2 is fixed to the cover 3, and the imaging element 502, which is an optical element, is driven in the Z direction by the optical element driving device 1, thereby forming an image of the subject on the imaging element 502.

[0028] [Optical element driving device body] The optical element driving device main body 4 is a main body portion of the optical element driving device 1 that drives the lens unit 2, which is an optical element, in the Z direction. For convenience of explanation, the following description will be given on the assumption that the optical element driving device 1 drives the lens unit 2, but as described above, the optical element driving device 1 may also drive the imaging element 502.

[0029] As shown in FIG. 3, the optical element driving device main body 4 includes a holding portion 10, a housing portion 20, a support portion 30, a driving portion 40, a biasing portion 50, adjustment portions 60A and 60B, a substrate portion 70, and the like.

[0030] The holding section 10, the accommodation section 20, the support section 30, the drive section 40, the adjustment sections 60A and 60B, and the substrate section 70 of the optical element driving device main body 4 will be described below with reference to Fig. 3 as well as Figs. 4 to 6. Fig. 4 is a perspective view showing the holding section 10 of the optical element driving device main body 4 shown in Fig. 3. Fig. 5 is a perspective view showing the accommodation section 20 of the optical element driving device main body 4 shown in Fig. 3 with the substrate section 70 removed. Fig. 6 is a perspective view showing the accommodation section 20 of the optical element driving device main body 4 shown in Fig. 3 with the substrate section 70 attached.

[0031] [Holding part] The holder 10 has a frame 12 with an opening 11 formed in the center, and the opening 11 is configured to be capable of holding the lens unit 2 shown in Fig. 2 inside. For example, the opening 11 is configured to be capable of holding the lens unit 2 on its inner peripheral surface by forming an attachment groove or the like on its inner peripheral surface. In this way, the holder 10 holds the lens unit 2 by surrounding the outer periphery of the lens unit 2.

[0032] Groove portions 14 extending along the Z direction are provided at multiple locations on outer peripheral surface 13, which is the outer peripheral side of frame portion 12. As an example, holding portion 10 has a rectangular outer shape in a plan view, and groove portions 14 are provided at two locations on first outer surface 13a corresponding to one side of the rectangle.

[0033] The groove portion 14 is provided corresponding to a shaft member 31 (described later) that extends along the Z direction, and the groove portion 14 and the shaft member 31 constitute the support portion 30. Here, the groove portion 14 is formed as a groove with a semicircular cross section corresponding to the shape of the cylindrical shaft member 31, and is configured to come into slidable contact with the shaft member 31 in the Z direction. The holding portion 10 is supported by the support portion 30 so as to be movable in the Z direction.

[0034] Further, a magnet 41 constituting a driving unit 40 is provided on the frame 12. Specifically, the magnet 41 is attached to a recess 15 provided on the first outer surface 13a. The holding unit 10 is configured to be movable in the Z direction by the driving unit 40 having the magnet 41 and a coil 42 described later.

[0035] Although the opening 11 is formed in a cylindrical shape to correspond to the cylindrical lens portion 2, the shape of the opening 11 can be changed to an appropriate shape to correspond to the shape of the lens portion 2.

[0036] Furthermore, when the optical element driving device 1 drives the imaging element 502, the holding portion 10 does not need to have an opening 11, that is, the holding portion 10 does not need to be a frame portion. In that case, for example, the imaging element 502 may be held on the upper surface (light receiving surface) of the holding portion 10.

[0037] [Containment section] The accommodating portion 20 (fixed portion in the present invention) has a frame portion 22 with an accommodating opening 21 formed in the center, and the accommodating opening 21 is configured to surround the outer periphery of the holding portion 10 so as to be able to accommodate the holding portion 10 inside.

[0038] An inner circumferential surface 23 on the inside of the accommodation opening 21 is formed to correspond to the shape of the outer circumferential surface 13 of the holding part 10 in a plan view. A shaft member 31 constituting a support part 30 is provided on the inner circumferential surface 23 on the side of a first inner surface 23a facing the first outer surface 13a of the holding part 10. Specifically, as shown in Figs. 5 and 6, a cylindrical shaft member 31 extending along the Z direction is provided so as to stand on a bottom part 27 of the accommodation opening 21. The accommodation part 20 supports the holding part 10 movably in the Z direction by a plurality of support parts 30 each having a groove part 14 and a shaft member.

[0039] Furthermore, in the frame 22 of the housing unit 20, a coil 42 constituting the drive unit 40 is provided on a first side 22a facing the first outer surface 13a. When a current is applied to the coil 42, the drive unit 40 moves the holding unit 10 in the Z direction relative to the housing unit 20 due to an interaction between the applied current and the magnetic field of the magnet 41. The holding unit 10 functions as a movable unit driven by the drive unit 40, and the housing unit 20 functions as a fixed unit relative to the holding unit 10.

[0040] In addition, in FIG. 3, the shapes of the outer peripheral surface 13 of the holding portion 10 and the inner peripheral surface 23 of the accommodation opening 21 are merely examples, and can be appropriately changed depending on, for example, the arrangement of the support portion 30 and the drive portion 40, etc.

[0041] [Support part] The support parts 30 support the holding part 10 movably in the Z direction relative to the accommodation part 20. As an example, the support parts 30 are disposed at two different positions in the circumferential direction of the outer circumferential surface 13 and the inner circumferential surface 23 in a plan view as shown in Fig. 3. More specifically, the support parts 30 are disposed at positions on the first outer surface 13a and the first inner surface 23a facing each other, sandwiching the drive part 40 therebetween.

[0042] As an example, the support part 30 has the groove part 14 of the holding part 10 described above and a shaft member 31 (the support member in the present invention). As described above, the groove part 14 is configured to be in slidable contact with the shaft member 31 in the Z direction.

[0043] In this embodiment, as described below, in the biasing unit 50 having the magnet 41 and the yoke 51, the magnet 41 magnetically attracts the yoke 51, thereby biasing the groove portion 14 toward the shaft member 31. That is, the biasing unit 50 applies a force in the -X direction to the holding unit 10 by a magnetic force Fa (a first magnetic force in the present invention), thereby biasing the holding unit 10 toward the shaft member 31. As a result, the support unit 30 holds the holding unit 10 like a cantilever support structure, so to speak.

[0044] In this way, the support portion 30 has a groove portion 14 extending along the Z direction and a shaft member 31, and the biasing portion 50 biases the groove portion 14 toward the shaft member 31, thereby suppressing tilt of the holding portion 10.

[0045] In addition, the shaft member 31 is provided at the bottom 27 of the accommodating opening 21 and is fixed to the accommodating section 20 side which functions as a fixing section for the holding section 10, thereby enabling stable operation of the holding section 10 when adjusting the biasing force F applied to the shaft member 31 described below.

[0046] Furthermore, since the groove portion 14 is configured to be in slidable contact with the shaft member 31 in the Z direction, the accommodating portion 20 can support the holding portion 10 via the support portion 30 so as to be movable in the Z direction.

[0047] In this embodiment, as an example, the support portion 30 is configured such that the holding portion 10 has a groove portion 14 and the accommodating portion 20 has a shaft member 31, but the support portion 30 may also be configured such that the holding portion 10 has a shaft member 31 and the accommodating portion 20 has a groove portion 14.

[0048] The shaft member 31 may be another member as long as it is configured to be in slidable contact with the groove portion 14. For example, a protruding portion may be provided that protrudes inward from the inner circumferential surface 23 of the storage portion 20 and extends in the Z direction, and the groove portion 14 may be in slidable contact with the protruding portion.

[0049] Furthermore, as long as the groove portion 14 can come into slidable contact with the shaft member 31, it is not limited to a groove having a semicircular cross section, and may be a groove having a V-shaped cross section, a U-shaped cross section, or the like.

[0050] [Drive unit] The driving unit 40 is an actuator that drives the holding unit 10 in the Z direction relative to the accommodation unit 20. As an example, the driving unit 40 is disposed between the support units 30 disposed in two locations, as shown in FIG.

[0051] Driving unit 40 has a magnet 41 (first magnet in the present invention) attached to holding unit 10 and a coil 42 (first coil in the present invention) attached to housing unit 20. Driving unit 40 having such a configuration functions as a moving magnet type voice coil motor (VCM: Voice Coil Motor).

[0052] The magnet 41 is attached to the recess 15 provided in the first outer surface 13a of the holder 10, as described above.

[0053] The coil 42 is attached to the first side portion 22a of the accommodation portion 20. Specifically, the coil 42 is attached to an inner surface of a substrate portion 70 (substrate 71) described below, as shown in Fig. 5. Then, when the substrate portion 70 is attached to the outer peripheral surface 24 of the accommodation portion 20, as shown in Fig. 6, the coil 42 is disposed in a penetration portion 25 penetrating the frame portion 22 of the accommodation portion 20. When the holding portion 10 is accommodated in the accommodation portion 20, the magnet 41 and the coil 42 are disposed at a distance from each other so as to face each other in the radial direction.

[0054] The coil 42 is composed of a wire wound around a winding axis along the X direction. The magnet 41 is magnetized so that a magnetic field is formed across the coil 42 in the radial direction, for example, so that the +Z direction side is an S pole and the -Z direction side is an N pole.

[0055] When no power is supplied to the coil 42 (when no current is flowing), the holding unit 10 is supported (self-held) at a reference position by, for example, a magnetic force Fa (magnetic force with which the magnet 41 magnetically attracts the yoke 51) of the biasing unit 50 described below. When power is supplied to the coil 42 (when current is flowing) through wiring not shown, a Lorentz force is generated in the coil 42 due to an interaction between the current flowing through the coil 42 and the magnetic field of the magnet 41.

[0056] The direction of the Lorentz force is the Z direction, which is a direction perpendicular to the direction of the magnetic field generated by magnet 41 and the direction of the current flowing through coil 42. Since coil 42 is fixed to housing section 20, a reaction force acts on magnet 41, and this reaction force becomes the driving force of the VCM. When the direction and magnitude of the current flowing through coil 42 are controlled, holding section 10 having magnet 41 moves to the light receiving side in the optical axis direction or the image forming side in the optical axis direction with respect to the above-mentioned reference position, and focusing is performed.

[0057] Although not shown in the figures, the substrate 70, which will be described later, is provided with a Z-position detector that detects the position of the holder 10 in the Z direction relative to the accommodation unit 20. The optical element driving device 1 controls the direction and magnitude of the current flowing through the coil 42 based on the Z-direction position detected by the Z-position detector. As the Z-position detector, for example, a magnet for detecting position and a Hall sensor that detects the magnetic field caused by the magnet are used.

[0058] The optical element driving device 1 can drive the lens unit 2 together with the holder 10 in the Z direction by the support unit 30 and the drive unit 40 described above, thereby achieving an AF function.

[0059] Although the holding unit 10 is configured here to be movable in the Z direction by one driving unit 40, it may be configured to be movable in the Z direction by a plurality of driving units 40.

[0060] [Electricity applying part] The biasing portion 50 biases the holding portion 10 against the shaft member 31 provided in the storage portion 20. As an example, the biasing portion 50 is disposed between the support portions 30 disposed in two locations, as shown in FIG.

[0061] As an example, the biasing unit 50 has the magnet 41 of the holding unit 10 described above, and a yoke 51 made of a magnetic material and attached to the housing unit 20. The magnet 41 is used in both the driving unit 40 and the biasing unit 50.

[0062] The yoke 51 is attached to the first side portion 22a of the housing portion 20. Specifically, the yoke 51 is attached to an outer surface of a substrate portion 70 (substrate 71) described below, as shown in Fig. 5. When the substrate portion 70 is attached to the outer peripheral surface 24 of the housing portion 20 and the holding portion 10 is housed in the housing portion 20, the magnet 41 and the yoke 51 are disposed radially opposite and spaced apart from each other.

[0063] With this configuration, the yoke 51 is magnetically attracted by the magnetic force of the magnet 41, and as a result, the holding portion 10 in which the magnet 41 is arranged is urged toward the shaft member 31 side of the accommodation portion 20 in which the yoke 51 is arranged. In other words, the urging portion 50 applies a force in the -X direction to the holding portion 10 by the magnetic force Fa, urging the groove portion 14 of the holding portion 10 toward the shaft member 31.

[0064] In this way, the biasing portion 50 biases the groove portion 14 toward the shaft member 31, so that tilt of the holding portion 10 can be suppressed.

[0065] In particular, when power is not being supplied to the coil 42 (when no current is flowing), the holding portion 10 is supported at the reference position by the force of the magnetic force Fa of the biasing portion 50, and is self-held.

[0066] In this embodiment, the magnet 41 is provided on the holding unit 10 side and the coil 42 is provided on the housing unit 20 side, but the arrangement may be reversed, with the coil 42 provided on the holding unit 10 side and the magnet 41 provided on the housing unit 20 side. In this case, the yoke 51 is disposed on the housing unit 20 side.

[0067] In addition, although the magnet 41 of the driving unit 40 is used to magnetically attract the yoke 51 here, a separate magnet may be provided to magnetically attract the yoke 51. In that case, the magnet may be disposed in a position different from that of the magnet 41 in the holding unit 10, and the yoke 51 may be disposed corresponding to this position.

[0068] [Adjustment section] The adjustment portions 60A and 60B are configured to adjust the biasing force F that biases the groove portion 14 against the shaft member 31. As an example, as shown in Fig. 3, the adjustment portions 60A and 60B are arranged at positions different from the biasing portion 50 in the circumferential direction of the outer circumferential surface 13 and the frame portion 22 in a plan view. Here, the adjustment portions 60A and 60B are arranged on the second outer surface 13b and the second side portion 22b, and the third outer surface 13c and the third side portion 22c, respectively, which are positions different from the first outer surface 13a and the first side portion 22a where the biasing portion 50 is arranged.

[0069] Adjustment section 60A has a magnet 61A (a second magnet in the present invention) attached to holding section 10 and a coil 62A (a second coil in the present invention) attached to accommodation section 20.

[0070] Specifically, the magnet 61A is attached to a recess 16A provided in the second outer surface 13b of the holder 10.

[0071] The coil 62A is attached to the second side 22b of the accommodation section 20. Specifically, the coil 62A is attached to the inner surface of the substrate section 70 (substrate 71) as shown in Fig. 5. Then, when the substrate section 70 is attached to the outer peripheral surface 24 of the accommodation section 20 as shown in Fig. 6, the coil 62A is disposed in the through-hole 26A that penetrates the frame section 22 (second side 22b) of the accommodation section 20. When the holding section 10 is accommodated in the accommodation section 20, the magnet 61A and the coil 62A are disposed at a distance from each other so as to face each other in the radial direction.

[0072] Coil 62A is composed of a wire wound around a winding axis along the Y direction. Magnet 61A is magnetized so that a magnetic field is formed that crosses coil 62A in the radial direction, for example, so that the -X direction side is an N pole and the +X direction side is an S pole.

[0073] When power is supplied to the coil 62A through wiring (not shown) (when energized), a Lorentz force is generated in the coil 62A due to interaction between the current flowing through the coil 62A and the magnetic field of the magnet 61A.

[0074] The direction of the Lorentz force is the X direction, which is a direction perpendicular to the direction of the magnetic field generated by magnet 61A and the direction of the current flowing through coil 62A. Since coil 62A is fixed to housing section 20, a magnetic force Fb (second magnetic force in the present invention) acts as a reactive force on magnet 61A, and this magnetic force Fb serves as an adjusting force for adjusting the biasing force F. Since magnetic force Fa acts in the -X direction, magnetic force Fb controls the direction and magnitude of the current flowing through coil 62A so that it acts in the +X direction.

[0075] Similarly, the adjustment unit 60B has a magnet 61B (a second magnet in the present invention) attached to the holding unit 10 and a coil 62B (a second coil in the present invention) attached to the housing unit 20.

[0076] Specifically, the magnet 61B is attached to a recess 16B provided in the third outer surface 13c of the holder 10.

[0077] The coil 62B is attached to the third side 22c of the accommodating section 20. Specifically, the coil 62B is attached to the inner surface of the substrate section 70 (substrate 71) as shown in Fig. 5. Then, when the substrate section 70 is attached to the outer circumferential surface 24 of the accommodating section 20 as shown in Fig. 6, the coil 62B is disposed in the through-hole 26B that penetrates the frame section 22 (third side 22c) of the accommodating section 20. When the holding section 10 is accommodated in the accommodating section 20, the magnet 61B and the coil 62B are disposed at a distance from each other so as to face each other in the radial direction.

[0078] Coil 62B is composed of a wire wound around a winding axis along the Y direction. Magnet 61B is magnetized so that a magnetic field is formed radially across coil 62B, for example, with the -X direction side as the N pole and the +X direction side as the S pole.

[0079] When power is supplied to coil 62B through wiring (not shown) (when energized), a Lorentz force is generated in coil 62B due to interaction between the current flowing through coil 62B and the magnetic field of magnet 61B.

[0080] The direction of the Lorentz force is the X direction, which is a direction perpendicular to the direction of the magnetic field generated by magnet 61B and the direction of the current flowing through coil 62B. Since coil 62B is fixed to housing section 20, a magnetic force Fc (second magnetic force in the present invention) acts as a reactive force on magnet 61B, and this magnetic force Fc serves as an adjusting force for adjusting the biasing force F. Since magnetic force Fa acts in the -X direction, the direction and magnitude of the current flowing through coil 62B are controlled so that magnetic force Fc acts in the +X direction.

[0081] In this manner, the biasing force F is adjusted by providing the adjustment units 60A and 60B which generate the magnetic forces Fb and Fc in the opposite direction to the magnetic force Fa generated by the biasing unit 50.

[0082] For example, when the diameter of the image sensor of the image sensor board 501 is increased to improve the image quality of the camera module A, the size of the lens unit 2 is also increased. When the size of the lens unit 2 is increased in diameter, the driving force for driving the lens unit 2 needs to be increased, and the magnetic force of the magnet 41 itself used to drive the lens unit 2 needs to be increased.

[0083] As the magnetic force of magnet 41 itself increases, the magnetic force between magnet 41 and yoke 51 also increases, so that the biasing force F biasing groove portion 14 against shaft member 31 increases, and the frictional force between shaft member 31 and groove portion 14 increases, which may hinder the movement of lens portion 2.

[0084] Therefore, in this embodiment, the adjustment units 60A and 60B having the above-described configuration are provided, and the biasing force F is adjusted by applying magnetic forces Fb and Fc in the opposite direction to the magnetic force Fa by the biasing unit 50.

[0085] For example, the biasing force F before adjustment by the adjustment units 60A and 60B is "1 / 2×Fa", but by adjustment by the adjustment units 60A and 60B, the biasing force F becomes "1 / 2×(Fa-Fb-Fc)". In this way, by adjustment by the adjustment units 60A and 60B, the biasing force F can be reduced compared to before adjustment. As a result, the frictional force between the shaft member 31 and the groove portion 14 is also reduced, allowing the lens portion 2 to move smoothly.

[0086] In this manner, in the present embodiment, by providing adjustment units 60A, 60B having the above-described configuration, the biasing force F can be adjusted, which is particularly useful when the magnetic force of the magnet 41 itself becomes large, and allows the lens unit 2 to move smoothly.

[0087] Further, here, the biasing unit 50 is disposed on one side of the rectangular holding unit 10 and storage unit 20, and the adjustment units 60A, 60B are disposed on two sides that are perpendicular to the one side. Therefore, the magnetic forces Fb, Fc by the adjustment units 60A, 60B only have components in the opposite direction to the magnetic force Fa by the biasing unit 50, and the biasing force F can be easily and stably adjusted.

[0088] In this embodiment, the biasing unit 50 is disposed on one side of the rectangular holding unit 10 and the housing unit 20, and the adjustment units 60A and 60B are disposed on the two sides of the rectangular holding unit 10 and the housing unit 20, respectively, but the configuration is not limited to this, and the positions and the number of the adjustment units 60A and 60B can be changed as appropriate. For example, the biasing force F may be adjusted by disposing one or more adjustment units on a side opposite to the side on which the biasing unit 50 is disposed.

[0089] Also, here, magnets 61A, 61B are provided on the holding portion 10 side, and coils 62A, 62B are provided on the storage portion 20 side, but the arrangement may be reversed, with coils 62A, 62B provided on the holding portion 10 side, and magnets 61A, 61B provided on the storage portion 20 side.

[0090] Similarly to the yoke 51 of the urging unit 50, the adjustment units 60A and 60B may have a yoke. In this case, similar to the yoke 51 of the urging unit 50, the yoke for the adjustment units 60A and 60B is attached to the outer surface of the substrate unit 70 (substrate 71) so as to face the magnets 61A and 61B.

[0091] By providing yokes for adjustment units 60A, 60B, it is possible to strengthen magnetic forces Fb, Fc and widen the adjustment range of biasing force F. Alternatively, even if the size of magnets 61A, 61B is reduced and the magnetic force of magnets 61A, 61B itself becomes smaller, desired magnetic forces Fb, Fc can be obtained and biasing force F can be adjusted.

[0092] [Board section] The substrate 70 supplies power to the coils 42, 62A, and 62B. The substrate 70 has the coils 42, 62A, and 62B, a yoke 51, and a substrate 71. The substrate 71 has wiring (not shown) formed thereon for supplying power to the coils 42, 62A, and 62B. Although not shown, the substrate 70 has a Z position detection unit (e.g., a Hall sensor or the like) that detects the position of the holding unit 10 in the Z direction relative to the accommodation unit 20, as described above.

[0093] In the substrate 71 of the substrate section 70, the coil 42, and the coils 62A and 62B are attached to the surface that will be on the inside when the substrate 71 is attached to the housing section 20. In the example shown in Fig. 5, the coil 42 is attached to the surface that will be on the inside of a central portion 71a that is the center part of the substrate 71, and the coils 62A and 62B are attached to the surfaces that will be on the inside of side portions 71b and 71c on both sides of the central portion 71a, respectively.

[0094] Furthermore, in the substrate 71 of the substrate portion 70, the yoke 51 is attached to a surface that will be on the outside when the substrate is attached to the housing portion 20. In the example shown in Fig. 5, the yoke 51 is attached to a surface that will be on the outside of the central portion 71a. The yoke 51 is disposed to face the coil 42 with the central portion 71a of the substrate 71 in between.

[0095] In this manner, the substrate portion 70 on which the coil 42, the coils 62A, 62B, and the yoke 51 are arranged is attached to the outer peripheral surface 24 of the accommodating portion 20 so that the coil 42, the coils 62A, 62B are arranged in the through-holes 25, 26A, 26B of the accommodating portion 20, respectively.

[0096] In this way, by arranging coil 42, coils 62A, 62B, and yoke 51 on one substrate 71 and attaching substrate section 70 to outer peripheral surface 24 of housing section 20, coil 42, coils 62A, 62B, and yoke 51 can be arranged at desired positions in housing section 20. This makes it easy to assemble substrate section 70 to housing section 20, and also makes it easy to arrange coil 42, coils 62A, 62B, and yoke 51, improving layout flexibility.

[0097] Electric power is supplied to the substrate portion 70 under the control of, for example, the control unit 503 (see FIG. 2), which controls the energization of the coil 42 and the coils 62A and 62B, thereby moving the holder 10 in the Z direction.

[0098] Specifically, in the reference state, the control unit 503 does not energize the coil 42 and the coils 62A and 62B. In this reference state, the holding unit 10 is supported at the reference position (self-holding) by the force of the magnetic force Fa of the biasing unit 50 that magnetically attracts the yoke 51 to the magnet 41.

[0099] When the control unit 503 moves the holding unit 10 in the Z direction, it first energizes the coils 62A and 62B to cause the adjustment units 60A and 60B to generate magnetic forces Fb and Fc in the opposite direction to the magnetic force Fa generated by the biasing unit 50. This reduces the biasing force F to be less than before the biasing force F was applied to the coils 62A and 62B.

[0100] Then, the control unit 503 energizes the coil 42 while keeping the biasing force F in a reduced state, and moves the holding unit 10 in the Z direction. At this time, since the biasing force F remains in a reduced state, the frictional force between the shaft member 31 and the groove portion 14 also becomes smaller, and the lens unit 2 can be moved smoothly.

[0101] At this time, the control unit 503 may change the magnetic forces Fb and Fc by the adjustment units 60A and 60B in consideration of the direction of gravity. For example, when the direction of gravity is the -X direction, the urging force F is a force due to the magnetic force Fa by the urging unit 50 plus a force due to the weight of the lens unit 2 and the holding unit 10. Therefore, in consideration of the force due to the weight of the lens unit 2 and the holding unit 10, the magnetic forces Fb and Fc by the adjustment units 60A and 60B are increased. On the other hand, when the direction of gravity is the +X direction, the urging force F is a force obtained by subtracting the force due to the weight of the lens unit 2 and the holding unit 10 from the force due to the magnetic force Fa by the urging unit 50. Therefore, in consideration of the force due to the weight of the lens unit 2 and the holding unit 10, the magnetic forces Fb and Fc by the adjustment units 60A and 60B are decreased.

[0102] Here, an example has been described in which the control unit 503 controls the current supply to the coils 42, 62A, and 62B, but a separate control unit may be provided on the substrate 71, and the control unit may control the current supply to the coils 42, 62A, and 62B.

[0103] [Other embodiments] The present invention is not limited to the above-described embodiment, and can be modified without departing from the spirit and scope of the present invention.

[0104] For example, in the above embodiment, the smartphone M has been described as an example, but the present invention can be applied to a camera-mounted device having a camera module and an image processing unit that processes image information obtained by the camera module. The camera-mounted device includes information devices and transport equipment. Information devices include, for example, camera-equipped mobile phones, notebook computers, tablet terminals, portable game consoles, web cameras, camera-equipped in-vehicle devices (for example, rear monitor devices, drive recorder devices), and the like. Transport equipment includes, for example, automobiles, drones, and the like.

[0105] 7A and 7B are diagrams showing an automobile V as a camera-mounted device equipped with an in-vehicle camera module VC (Vehicle Camera). FIG. 7A is a front view of the automobile V, and FIG. 7B 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 FIG. 7A and FIG. 7B, 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 a backup monitor, a drive recorder, a collision avoidance control, an automatic driving control, etc.

[0106] In the above embodiment, the optical element driving device 1 that drives the lens unit 2 as an optical element has been described, but the optical element to be driven may be an optical element other than a lens, such as a mirror or a prism, or an optical element such as the imaging element 502. In this case, the shape of the opening 11 of the holder 10 may be changed according to the shape of the optical element to be attached, or may be eliminated in some cases.

[0107] Furthermore, in the above embodiment, the optical element driving device 1 has an AF function, but it may have not only the AF function but also a function for moving the lens unit 2 in the Z direction, such as a zoom function.

[0108] In the above embodiment, the optical element driving device 1 having the AF function has been described as an example, but the optical element driving device 1 may have an OIS function. When the optical element driving device 1 has the OIS function, the optical element driving device 1 includes a base that supports the housing unit 20 movably in the X direction and the Y direction via the OIS support unit, and an OIS driving unit that drives the housing unit 20 in the X direction and the Y direction relative to the base. In this case, a biasing unit and an adjustment unit having the same configuration as the biasing unit 50 and the adjustment units 60A and 60B described above may be provided for the OIS support unit arranged between the housing unit 20 and the base, and the biasing force for the OIS support unit may also be adjusted as described above.

[0109] The above describes the embodiment 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 thereto. In other words, the description of the configuration of the above device and the shape of each part are examples, and it is clear that various modifications and additions to these examples are possible within the scope of the present invention. [Industrial Applicability]

[0110] The optical element driving device and camera module of the present invention are useful when installed in camera-mounted devices such as smartphones, mobile phones, digital cameras, notebook computers, tablet terminals, portable game consoles, in-vehicle cameras, and drones. [Explanation of symbols]

[0111] 1 Optical element driving device 2 Lens section 3 Cover 4. Optical element driving device main body 5. Imaging unit 10 Holding part 11 Opening 12 Frame section 13 Outer surface 14 Groove 15, 16A, 16B recess 20 Storage unit 21 Storage opening 22 Frame section 23 Inner surface 24 Outer surface 25, 26A, 26B penetrations 27 Bottom 30 Support part 31 Shaft member 40 Drive unit 41 Magnet 42 Coil 50 energizing section 51 York 60A, 60B adjustment section 61A, 61B Magnets 62A, 62B coils 70 Circuit Board 71 Substrate 301 Opening 501 Image sensor board 502 Image sensor 503 Control Unit

Claims

1. a holding portion capable of holding an optical element; a fixing portion that movably supports the holding portion via a support member; a drive unit that includes a first magnet disposed on one of the holding unit and the fixed unit, and a first coil disposed on the other, and that moves the holding unit; a yoke disposed on the other magnet opposite the first magnet and biasing the holding portion toward the support member; an adjustment unit including a second magnet disposed on one of the holding unit and the fixed unit, and a second coil disposed on the other, the adjustment unit adjusting the biasing force that biases the holding unit against the support member; a control unit that controls energization of the first coil and the second coil; Equipped with When moving the holding part, the control part energizes the second coil to reduce the biasing force compared to before energizing, and then energizes the first coil. Optical element driver.

2. the second magnet is disposed in the holding portion, The second coil is disposed on the fixed portion. The optical element driving device according to claim 1 .

3. the first magnet is disposed in the holding portion, the first coil is disposed on a substrate together with the second coil, and the substrate is disposed on the fixed portion; The optical element driving device according to claim 2 .

4. The support member is disposed on the fixing portion. The optical element driving device according to claim 1 .

5. The optical element driving device according to any one of claims 1 to 4, an imaging unit that captures an image of a subject using 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