Driving device, camera module, and camera mounting device

Abstract

To provide a driving device configured to improve the thrust of driving motion of both an AF driving part and an OIS driving part, a camera module, and a camera mounting device.SOLUTION: A driving device comprises a lens holder, a magnet holder housing a magnet part, a coil part, and an imaging element holding part. The magnet part includes an AF magnet and an OIS magnet. The coil part includes an AF coil and an OIS coil. The OIS magnet includes a first magnet and a second magnet arranged so as to be adjacent to the AF magnet in an optical axis direction. The first magnet includes magnetic poles which are arranged in the same direction of magnetic poles of the AF magnet. The second magnet includes magnetic poles which are arranged in a direction orthogonal to the direction in which the magnetic poles of the AF magnet are arranged. At least two second magnets are provided so as to hold the magnetic poles of the first magnet.SELECTED DRAWING: Figure 9

Description

[Technical Field]

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

[0002] Generally, mobile terminals such as smartphones are equipped with small camera modules. Such camera modules are equipped with a lens driving device that has an autofocus function (hereinafter referred to as the "AF function") that automatically performs autofocus when photographing a subject and an image stabilization function (hereinafter referred to as the "OIS function") that optically corrects shake (vibration) that occurs during photography to reduce image distortion.

[0003] A lens driving device having an AF function and an OIS function includes an autofocus driving unit (hereinafter referred to as an "AF driving unit") for moving a lens unit in the optical axis direction, and an image stabilization driving unit (hereinafter referred to as an "OIS driving unit") for oscillating the lens unit in a plane perpendicular to the optical axis direction. In Patent Document 1, a voice coil motor (VCM) is used in the AF driving unit and the OIS driving unit.

[0004] An autofocus movable part (hereinafter referred to as "AF movable part") that can move in the optical axis direction during autofocusing is disposed, for example, spaced apart in the radial direction from the autofocus fixed part (hereinafter referred to as "AF fixed part"). An image stabilization movable part (hereinafter referred to as "OIS movable part") that swings in a plane perpendicular to the optical axis during image stabilization is composed of an AF unit that includes an AF movable part, an AF fixed part, and an AF drive part, and is disposed, for example, spaced apart in the optical axis direction from the image stabilization fixed part (hereinafter referred to as "OIS fixed part"). The OIS movable part is connected to the OIS fixed part by an OIS support part such as a suspension wire, and is capable of swinging in a plane perpendicular to the optical axis.

[0005] In addition, the AF drive unit and the OIS drive unit are each provided with a coil and a magnet. The magnet serves both as a magnet for AF drive and a magnet for OIS drive, and is positioned so as to face both the AF coil and the OIS coil. Specifically, one of the AF coil and the OIS coil faces the magnet in a direction along which the south and north poles are aligned (for example, the horizontal direction). The other of the AF coil and the OIS coil faces the magnet in a direction different from the horizontal direction (for example, the vertical direction). [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2013-210550 Summary of the Invention [Problem to be solved by the invention]

[0007] Since magnetic flux flows in the horizontal direction of the magnet, a sufficient amount of magnetic flux flows through the coils facing each other in the horizontal direction, allowing the drive units corresponding to those coils to be driven with sufficient thrust.

[0008] However, for a coil facing the magnet in a vertical direction different from the horizontal direction, magnetic flux flows from the north pole to the south pole located on the opposite side, resulting in more magnetic flux flowing horizontally rather than vertically through the coil. In other words, the amount of magnetic flux flowing in a direction different from the direction of the coil facing the magnet is greater. Since such magnetic flux is difficult to utilize for the operation of the drive unit (e.g., OIS operation), there is a possibility that the drive unit corresponding to the coil cannot be driven with sufficient thrust. In other words, the configuration described in Patent Document 1 leaves room for improvement in terms of improving the thrust for the drive operations of both the AF drive unit and the OIS drive unit.

[0009] An object of the present invention is to provide a drive unit, a camera module, and a camera-mounted device that can improve the thrust of the drive operations of both the AF drive unit and the OIS drive unit. [Means for solving the problem]

[0010] The drive device according to the present invention comprises: a lens holder for holding a lens; a magnet holder that surrounds at least a portion of the lens holder and accommodates a magnet portion; a driving unit having the magnet unit and the coil unit; an imaging element holding portion that holds an imaging element facing the lens in the optical axis direction; Equipped with the magnet portion includes an autofocus magnet for driving the lens holder in the optical axis direction, and a shake correction magnet for driving the lens holder or the image sensor holding portion in an optical axis orthogonal direction that is perpendicular to the optical axis direction, the coil unit has an autofocus coil facing the autofocus magnet and a shake correction coil facing the shake correction magnet, the shake correction magnet includes a first magnet and a second magnet disposed adjacent to the autofocus magnet in the optical axis direction, the first magnet is arranged so that its magnetic poles are aligned in the same direction as the magnetic poles of the autofocus magnet, The second magnet is The magnet is arranged so that its magnetic poles are aligned in a direction perpendicular to the direction in which the magnetic poles of the autofocus magnet are aligned, At least two of the first magnets are provided so as to sandwich each magnetic pole of the first magnet.

[0011] The camera module according to the present invention comprises: The drive device; an element portion including the lens; an imaging unit including the imaging element that captures a subject image formed by the element unit; Equipped with.

[0012] The camera-equipped device according to the present invention comprises: A camera-equipped device that is an information device or a transportation device, The above camera module, an imaging control unit that processes image information obtained by the camera module; Equipped with. [Effects of the Invention]

[0013] According to the present invention, it is possible to improve the thrust force of the drive operation of both the AF drive unit and the OIS drive unit. [Brief explanation of the drawings]

[0014] [Figure 1A] FIG. 1 is a diagram showing a smartphone equipped with a camera module. [Figure 1B] FIG. 1 is a diagram showing a smartphone equipped with a camera module. [Figure 2] FIG. 2 is an external perspective view of the camera module. [Figure 3] FIG. 2 is a perspective view showing a state in which a cover of the lens driving device is removed. [Figure 4] FIG. 2 is an exploded perspective view showing a schematic configuration of the lens driving device. [Figure 5] FIG. 2 is an exploded perspective view showing a detailed configuration of the lens driving device. [Figure 6] FIG. 2 is an exploded perspective view showing a detailed configuration of the lens driving device. [Figure 7] FIG. 2 is a view of the lens driving device as seen from the optical axis direction. [Figure 8A] FIG. 2 is a perspective view of a drive magnet. [Figure 8B] FIG. 2 is an exploded perspective view of a drive magnet. [Figure 9] FIG. 3 is a simplified cross-sectional view of a drive magnet portion of the lens drive device. [Figure 10]4A and 4B are diagrams for explaining the positional relationship between a drive magnet and a coil portion. [Figure 11] 10A and 10B are diagrams for explaining the flow of magnetic flux of a drive magnet in a conventional example. [Figure 12] 5A and 5B are diagrams for explaining the flow of magnetic flux of a drive magnet in the present embodiment. [Figure 13] FIG. 2 is a simplified cross-sectional view of a drive magnet portion of a lens drive device according to a sensor shift type configuration. [Figure 14A] FIG. 1 is a diagram showing a car equipped with a camera module. [Figure 14B] FIG. 1 is a diagram showing a car equipped with a camera module. DETAILED DESCRIPTION OF THE INVENTION

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

[0016] 1A and 1B are diagrams showing a smartphone M (an example of a camera-equipped device) equipped with a camera module A according to an embodiment of the present invention, in which Fig. 1A is a front view of the smartphone M and Fig. 1B is a rear view of the smartphone M.

[0017] In this embodiment, the camera module A is applied to the rear camera OC1 of the smartphone M. The camera module A has an AF function and an OIS function, and can automatically perform autofocus when photographing a subject, and can also optically correct shake (vibration) that occurs during photography to capture images without image blur.

[0018] Fig. 2 is a perspective view of the appearance of camera module A. As shown in Fig. 2, the embodiment will be described using a Cartesian coordinate system (X, Y, Z). The same Cartesian coordinate system (X, Y, Z) will also be used in the figures described below. Furthermore, the intermediate directions that form 45° with the X direction and the Y direction, i.e., the diagonal directions in the planar view of camera module A when viewed from the optical axis direction, will be described as the U direction and the V direction.

[0019] When actually taking a photograph with the 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-back direction. That is, the Z direction is the optical axis direction, and the upper side in the drawing is the optical axis direction light receiving side (also called the "macro position side"), and the lower side is the optical axis direction image forming side (also called the "infinity position side"). Also, the X direction and Y direction perpendicular to the Z axis are called the "optical axis perpendicular direction."

[0020] The camera module A includes a lens driving device 1 that realizes AF and OIS functions, a lens unit 2 in which a lens is housed in a cylindrical lens barrel, and an imaging unit 3 that captures the subject image formed by the lens unit 2.

[0021] The imaging unit 3 is disposed on the imaging side in the optical axis direction of the lens driving device 1. The imaging unit 3 includes, for example, an image sensor board 41, an imaging element 42, and a control unit 43 that controls the driving of the lens driving device 1. The lens driving device 1 is mounted on the image sensor board 41 and is mechanically and electrically connected thereto. The imaging element 42 is configured by, for example, a CCD (charge-coupled device) image sensor or a CMOS (complementary metal oxide semiconductor) image sensor. The imaging element 42 is mounted on the image sensor board 41 and captures an image of a subject formed by the lens unit 2. The control unit 43 controls the driving of the lens driving device 1. The control unit 43 may be mounted on the image sensor board 41, or may be provided in a camera-equipped device (in this embodiment, a smartphone M) in which the camera module A is mounted.

[0022] As shown in FIG. 3, the lens driving device 1 has a driving device main body (reference numeral omitted) that is covered on the outside with a cover 25. The cover 25 is a rectangular cylinder with a lid that is rectangular in plan view from the optical axis direction, and has an opening 251 on its top surface. The lens unit 2 faces the outside through this opening 251. The cover 25 is fixed to the base 21 of the lens driving device 1, for example, by adhesive. That is, the lens driving device 1 has a rectangular shape that extends in the X and Y directions in plan view from the optical axis direction. In the following description, "plan view" means a plan view from the optical axis direction.

[0023] Fig. 4 is an exploded perspective view showing a schematic configuration of the lens driving device 1. Figs. 5 and 6 are exploded perspective views showing a detailed configuration of the lens driving device 1. Note that the cover 25 is omitted in Figs. 4 to 6.

[0024] Functionally, as shown in FIG. 4, the lens driving device 1 includes an OIS movable part M1, an OIS fixed part F1, an OIS driving part D1, an OIS support part S1, an AF movable part M2, an AF fixed part F2, an AF driving part D2, and an AF support part S2.

[0025] The OIS movable part M1 is a part that receives the driving force of the OIS driving part D1 and oscillates in a plane perpendicular to the optical axis during shake correction, and in this embodiment is composed of an AF unit that includes an AF movable part M2, an AF fixed part F2, an AF driving part D2, and an AF support part S2.

[0026] The OIS fixed portion F1 is a portion that supports the OIS movable portion M1, and in this embodiment is formed by a base 21. The OIS fixed portion F1 is disposed, for example, at a distance from the OIS movable portion M1 on the imaging side in the optical axis direction.

[0027] The OIS support part S1 is a part that connects the OIS movable part M1 and the OIS fixed part F1, and supports the OIS movable part M1 so that it can swing in a plane perpendicular to the optical axis. In this embodiment, the OIS support part S1 is made up of suspension wires 24 arranged at the four corners.

[0028] The OIS driving unit D1 is composed of OIS coils 23A-23D arranged on the OIS fixed unit F1 and driving magnets 14A-14D (OIS magnets) arranged on the OIS movable unit M1. That is, a moving magnet type voice coil motor is applied to the OIS driving unit D1. The OIS driving unit D1 may also be composed of a moving coil type voice coil motor.

[0029] The AF movable part M2 is a part that receives the driving force of the AF driving part D2 and moves in the optical axis direction during autofocusing, and is made up of the lens holder 11 in this embodiment.

[0030] The AF fixed part F2 is a part that supports the AF movable part M2, and in this embodiment is configured by a magnet holder 12. The AF fixed part F2 is disposed, for example, radially outwardly and spaced apart from the AF movable part M2.

[0031] The AF support part S2 is a part that connects the AF movable part M2 and the AF fixed part F2, and in this embodiment, it is composed of an upper elastic support member 15 that is arranged on the light receiving side (upper side) in the optical axis direction, and a lower elastic support member 16 that is arranged on the imaging side (lower side) in the optical axis direction.

[0032] The AF driving unit D2 is a part that drives the AF movable unit M2 during autofocusing, and in this embodiment is composed of an AF coil 13 arranged in the AF movable unit M2 and driving magnets 14A to 14D (AF magnets) arranged in the AF fixed unit F2. That is, a moving coil type voice coil motor is applied to the AF driving unit D2 in this embodiment. The AF driving unit D2 may also be composed of a moving magnet type voice coil motor.

[0033] A guaranteed stroke, which indicates the degree to which shake correction can be performed appropriately, is specified for the lens driving device 1. That is, the shapes, sizes, strengths, etc. of the constituent members of the OIS movable part M1, OIS fixed part F1, OIS driving part D1, and OIS support part S1 are set so as to realize the guaranteed stroke.

[0034] Structurally, as shown in Figures 5 and 6, the lens driving device 1 has a lens holder 11, a magnet holder 12, an AF coil 13, driving magnets 14A to 14D, an upper elastic support member 15, a lower elastic support member 16, a base 21, a coil substrate 22, OIS coils 23A to 23D, and a suspension wire 24.

[0035] The lens holder 11 is a member that functions as the AF movable portion M2, and holds the lens portion 2 (see FIG. 2) in a cylindrical lens housing portion 111. The lens portion 2 is fixed to the lens housing portion 111 by adhesive or screwing. In this embodiment, the lens holder 11 has a roughly octagonal outer shape in a plan view. An AF coil 13 is attached to the peripheral surface of the lens holder 11.

[0036] The lens holder 11 has, on its upper surface (the upper end surface of the lens housing portion 111), an upper spring fixing portion 112 to which the upper elastic support member 15 is fixed. The upper spring fixing portion 112 is provided with, for example, a positioning boss (reference number omitted) that protrudes toward the light receiving side in the optical axis direction, and the upper elastic support member 15 is positioned by this positioning boss.

[0037] The lens holder 11 has, on its lower surface, a lower spring fixing portion 113 to which the lower elastic support member 16 is fixed. The lower spring fixing portion 113 is provided with, for example, a positioning boss (reference number omitted) that protrudes toward the imaging side in the optical axis direction, and the lower elastic support member 16 is positioned by this positioning boss.

[0038] The lens holder 11 also has, on its upper surface, a tethering portion 114 to which an end of the AF coil 13 is connected. The lens holder 11 also has a protrusion 115 that protrudes radially outward on the upper portion of the outer circumferential surface of the lens housing portion 111. In this embodiment, the protrusions 115 are provided at four locations that face each other in the X and Y directions.

[0039] The magnet holder 12 is a holding member having a generally rectangular cylindrical shape in plan view, with four connected side walls 122. The magnet holder 12 has an opening 121 cut out in a portion corresponding to the generally octagonal outer shape of the lens holder 11 in plan view.

[0040] The magnet holder 12 has magnet holding portions 123 inside the connecting portions (four corners of the magnet holder 12) of the four side wall bodies 122. The drive magnets 14A to 14D are fixed to the magnet holding portions 123. For example, the magnet holding portions 123 are provided with openings (reference numeral omitted) that communicate with the outside, so that adhesive can be injected onto the contact surfaces between the magnet holding portions 123 and the drive magnets 14A to 14D.

[0041] The magnet holder 12 has a wire insertion portion 124 that is recessed in an arc shape radially inward above the connecting portion on the outer circumferential surface of the side wall body 122. The suspension wire 24 is placed in the wire insertion portion 124. By providing the wire insertion portion 124, it is possible to avoid interference between the suspension wire 24 and the magnet holder 12 when the OIS movable part M1 swings.

[0042] The magnet holder 12 has an upper spring fixing portion 126 for fixing the upper elastic support member 15 on the upper surface of the side wall body 122. In the upper spring fixing portion 126, the peripheral edge of the wire insertion portion 124 is recessed downward from the mounting surface of the upper elastic support member 15, so that a gap is formed when the upper elastic support member 15 is mounted.

[0043] The magnet holder 12 also has a lower spring fixing portion 127 on the lower surface of the side wall 122 for fixing the lower elastic support member 16 .

[0044] The magnet holder 12 has a recess 125 recessed from the light receiving side toward the imaging side in the optical axis direction at a position corresponding to the protrusion 115 of the lens holder 11 on the upper part of the side wall 122. When the lens holder 11 moves toward the imaging side in the optical axis direction, the protrusion 115 of the lens holder 11 engages with the recess 125 of the magnet holder 12, thereby restricting the movement of the lens holder 11 toward the imaging side in the optical axis direction.

[0045] In addition, a plurality of protrusions 128 that protrude toward the light receiving side in the optical axis direction are provided on the top surface of magnet holder 12. Providing protrusions 128 makes it possible to prevent direct collision between cover 25 and the main parts of lens driving device 1 when an external force in the optical axis direction is applied due to a fall or the like, and to suppress breakdowns in lens driving device 1.

[0046] Furthermore, the magnet holder 12 has a movable-side restricting portion 129 that restricts the movement of the OIS movable portion M1 in the U and V directions.

[0047] The AF coil 13 is an air-core coil that is energized during autofocusing, and is wound around the outer circumferential surface of the coil winding portion of the lens holder 11. The AF coil 13, together with the drive magnets 14A to 14D, constitutes a voice coil motor that functions as the AF drive unit D2. Both ends of the AF coil 13 are respectively wound around the winding portion 114 of the lens holder 11. The AF coil 13 is energized via, for example, a suspension wire 24 and an upper elastic support member 15. The current flowing through the AF coil 13 is controlled by, for example, the control unit 43.

[0048] The drive magnets 14A to 14D are fixed to the magnet holding portions 123 of the magnet holder 12, for example, by adhesive. In this embodiment, the drive magnets 14A to 14D have a substantially isosceles trapezoidal shape in a plan view. This allows the spaces at the corners of the magnet holder 12 (the magnet holding portions 123) to be used effectively.

[0049] The drive magnets 14A to 14D are disposed so as to be spaced apart from the AF coil 13 in the radial direction and spaced apart from the OIS coils 23A to 23D in the optical axis direction. The drive magnets 14A to 14D are magnetized so as to form a magnetic field that crosses the AF coil 13 in the radial direction (U direction or V direction) and crosses the OIS coils 23A to 23D in the optical axis direction (Z direction). The drive magnets 14A to 14D, together with the AF coil 13, constitute a voice coil motor that functions as the AF drive unit D2. The drive magnets 14A to 14D correspond to the "magnet unit" of the present invention. Details of the drive magnets 14A to 14D will be described later.

[0050] The upper elastic support member 15 elastically supports the lens holder 11, which is the AF movable part M2, on the light receiving side in the optical axis direction relative to the magnet holder 12, which is the AF fixed part F2. The upper elastic support member 15 is formed, for example, from titanium copper, nickel copper, stainless steel, or the like. The upper elastic support member 15 has a rectangular shape as a whole in a plan view, i.e., the same shape as the magnet holder 12. The upper elastic support member 15 is made of two leaf springs and is arranged on the magnet holder 12 so as not to come into contact with each other. The upper elastic support member 15 is formed, for example, by etching a single piece of sheet metal.

[0051] The upper elastic support member 15 has a lens holder fixing portion 151 fixed to the lens holder 11, a magnet holder fixing portion 152 fixed to the magnet holder 12, and an arm portion 153 that elastically deforms as the lens holder 11 moves.

[0052] The lens holder fixing portion 151 has a shape corresponding to the upper spring fixing portion 112 of the lens holder 11. The lens holder fixing portion 151 is displaced together with the lens holder 11 when the lens holder 11 moves in the optical axis direction. The magnet holder fixing portion 152 has a shape corresponding to the upper spring fixing portion 126 of the magnet holder 12. The arm portion 153 connects the lens holder fixing portion 151 and the magnet holder fixing portion 152. The arm portion 153 has a winding shape and is easily elastically deformed when the lens holder 11 moves.

[0053] The upper elastic support member 15 is positioned relative to the lens holder 11 and the magnet holder 12 and fixed by, for example, adhesive. A part of the lens holder fixing portion 151 is electrically connected, for example, by soldering, to the AF coil 13 that is wound around the winding portion 114 of the lens holder 11. In addition, an end (corner) of the magnet holder fixing portion 152 is connected to the suspension wire 24 (wire connecting portion 154). The upper elastic support member 15, together with the suspension wire 24, forms a power supply path from the terminal fitting 27 to the AF coil 13.

[0054] The lower elastic support member 16 elastically supports the lens holder 11, which is the AF movable part M2, on the imaging side in the optical axis direction relative to the magnet holder 12, which is the AF fixed part F2. The lower elastic support member 16 is formed, for example, from titanium copper, nickel copper, stainless steel, or the like. The lower elastic support member 16 has a rectangular shape as a whole in a plan view, i.e., the same shape as the magnet holder 12. The lower elastic support member 16 is formed, for example, by etching a single piece of sheet metal.

[0055] The lower elastic support member 16 has a lens holder fixing portion 161 fixed to the lens holder 11, a magnet holder fixing portion 162 fixed to the magnet holder 12, and an arm portion 163 that elastically deforms as the lens holder 11 moves.

[0056] The lens holder fixing portion 161 has a shape corresponding to the lower spring fixing portion 113 of the lens holder 11. The lens holder fixing portion 161 is displaced together with the lens holder 11 when the lens holder 11 moves in the optical axis direction. The magnet holder fixing portion 162 has a shape corresponding to the upper spring fixing portion 128 of the magnet holder 12. The arm portion 163 connects the lens holder fixing portion 161 and the magnet holder fixing portion 162. The arm portion 163 has a winding shape and is easily elastically deformed when the lens holder 11 moves.

[0057] The lower elastic support member 16 is positioned relative to the lens holder 11 and the magnet holder 12 and fixed thereto by, for example, adhesive.

[0058] Base 21 has a rectangular shape in a plan view, with a circular opening 211 formed in the center. In camera module A, image sensor board 41 having image sensor 42 mounted thereon is disposed on the image forming side of base 21 in the optical axis direction. Base 21 corresponds to the "image sensor holding portion" of the present invention.

[0059] Terminal fittings 26 and 27 are embedded in the base 21 by, for example, insert molding.

[0060] The terminal fittings 26 are electrically connected to the wiring pattern of the image sensor board 41, and form a power supply line for supplying power to the OIS coils 23A to 23D and the magnetic sensors 31A and 31B, as well as a signal line for the detection signals output from the magnetic sensors 31A and 31B.

[0061] The terminal fittings 27 are exposed from the four corners of the base 21 and are connected by soldering to the other ends of the suspension wires 24. Two of the four terminal fittings 27 are electrically connected to the wiring pattern of the image sensor board 41 and form a power supply line for supplying power to the AF coil 13.

[0062] The base 21 also has a fixed-side restricting portion 212. The fixed-side restricting portion 212, together with the movable-side restricting portion 129 of the magnet holder 12, restricts movement of the OIS movable portion M1 in the U and V directions.

[0063] The coil substrate 22 is a substrate that is rectangular in plan view, similar to the base 21, and has a circular opening 221 in the center. The coil substrate 22 has a wiring pattern (not shown) that includes power lines for supplying power to the OIS coils 23A to 23D and the magnetic sensors 31A and 31B, and signal lines for detection signals output from the magnetic sensors 31A and 31B. The wiring pattern is electrically connected to terminal fittings 26 arranged on the base 21.

[0064] The OIS coils 23A to 23D are disposed at positions facing the drive magnets 14A to 14D in the optical axis direction. The OIS coils 23A to 23D are formed inside the coil substrate 22 during the manufacturing process of the coil substrate 22, for example.

[0065] The OIS coils 23A-23D are air-core coils that are energized during shake correction. The sizes and arrangements of the OIS coils 23A-23D and the drive magnets 14A-14D are set so that the radial edges of the drive magnets 14A-14D fit within the cross-sectional width of each of the OIS coils 23A-23D, i.e., so that the magnetic field radiated from the bottom surfaces of the drive magnets 14A-14D crosses two opposing sides of the OIS coils 23A-23D and returns to the drive magnets 14A-14D. Here, the OIS coils 23A-23D have a shape similar to the planar shape of the drive magnets 14A-14D (here, a substantially isosceles trapezoidal shape). This allows for efficient generation of a drive force (electromagnetic force) for oscillating the OIS movable part M1 in a plane perpendicular to the optical axis. The current flowing through the OIS coils 23A-23D is controlled, for example, by the control unit 43.

[0066] OIS coils 23A and 23C arranged opposite each other in the U direction and OIS coils 23B and 23D arranged opposite each other in the V direction are connected and the same current is passed through them. Drive magnets 14A and 14C and OIS coils 23A and 23C form an OIS voice coil motor that swings OIS movable part M1 in the U direction. Drive magnets 14B and 14D and OIS coils 23B and 23D form an OIS voice coil motor that swings OIS movable part M1 in the V direction.

[0067] Magnetic sensors 31A and 31B are mounted on the lower surface of coil substrate 22. Magnetic sensors 31A and 31B are configured, for example, with Hall elements or TMR (Tunnel Magneto Resistance) sensors, and are disposed in positions facing drive magnets 14A and 14B, respectively, in the optical axis direction. In this embodiment, magnetic sensors 31A and 31B are disposed on the backsides of the air-core portions of OIS coils 23A and 23B, respectively.

[0068] The magnetic field formed by the drive magnets 14A and 14B is detected by the magnetic sensors 31A and 31B, thereby enabling the position of the OIS movable part M1 in a plane perpendicular to the optical axis to be identified. That is, in this embodiment, the magnetic sensors 31A and 31B and the drive magnets 14A and 14B constitute an XY position detection part. Note that, in addition to the drive magnets 14A and 14B, magnets for detecting the XY positions of the OIS movable part M1 may be disposed on the OIS movable part M1. That is, in this embodiment, the drive magnets 14A and 14B also serve as magnets for detecting the XY positions.

[0069] The suspension wires 24 are linear members extending in the optical axis direction and elastically deform in response to the swing of the OIS movable part M1. One end of the suspension wires 24 (the end on the light-receiving side in the optical axis direction, the upper end) is fixed to the OIS movable part M1 (the upper elastic support member 15 in this embodiment), and the other end (the end on the imaging side in the optical axis direction) is fixed to the OIS fixed part F1 (the base 21 in this embodiment). In this embodiment, two of the four suspension wires 24, together with the upper elastic support member 15, are used as a power supply path to the AF coil 13.

[0070] When shake correction is performed in the lens driving device 1, current is passed through the OIS coils 23A to 23D. Specifically, the OIS driving unit controls the current passing through the OIS coils 23A to 23D based on a detection signal from a shake detection unit (not shown, for example, a gyro sensor) so as to cancel out shake of the camera module A. At this time, by feeding back the detection results of the magnetic sensors 31A and 31B, it is possible to accurately control the swing of the OIS movable part M1.

[0071] When current is applied to the OIS coils 23A-23D, the magnetic field of the drive magnets 14A-14D interacts with the current flowing through the OIS coils 23A-23D, generating a Lorentz force in the OIS coils 23A-23D (Fleming's left-hand rule). The direction of the Lorentz force is perpendicular (V or U direction) to the direction of the magnetic field (Z direction) and the direction of the current (U or V direction) in the long sides of the OIS coils 23A-23D. Because the OIS coils 23A-23D are fixed, a reaction force acts on the drive magnets 14A-14D. This reaction force becomes the driving force for the OIS voice coil motor, causing the OIS movable part M1, which has the drive magnets 14A-14D, to swing in the XY plane, thereby correcting shake.

[0072] Next, the drive magnets 14A to 14D will be described in detail. Since the drive magnets 14A to 14D each have the same configuration, the reference numerals A, B, C, and D will be omitted in the following description unless otherwise specified. Fig. 7 is a view of the lens drive device 1 as seen from the optical axis direction (Z direction). Note that in Fig. 7, the lens holder 11, magnet holder 12, etc. are omitted in order to show the positional relationship between the drive magnet 14, the AF coil 13, and the OIS coil.

[0073] 7, the four drive magnets 14 are held by magnet holders 12 (not shown) so as to be located at positions corresponding to the four corners of a rectangular base 21. Specifically, two drive magnets 14 are arranged on each of the diagonal lines along the U direction and the V direction of the rectangular shape of the base 21.

[0074] As shown in FIGS. 8A, 8B, and 9, the drive magnet 14 has an AF (autofocus) magnet 141, an OIS (image stabilizer) magnet 142, and a cover portion 143.

[0075] The AF magnets 141 are used to drive the lens holder 11 in the optical axis direction (Z direction), and together with the AF coil 13, constitute the AF drive unit D2. As described above, each of the four AF magnets 141 is configured in a substantially isosceles trapezoidal shape in a plan view, and is disposed so as to face the outer circumferential surface of the AF coil 13. In other words, the four AF magnets 141 are disposed so as to surround the AF coil 13 on all sides.

[0076] The AF magnet 141 is composed of a single-pole magnet. The AF magnet 141 is magnetized so that the side 141A facing the AF coil 13 is the north pole and the side 141B not facing the AF coil is the south pole in the direction facing the AF coil 13. In other words, the AF magnet 141 is arranged so that the magnetic poles are aligned in a direction (U direction or V direction) along the XY plane (plane orthogonal to the optical axis) that is orthogonal to the Z direction.

[0077] Specifically, two AF magnets 141 arranged diagonally along the U direction are arranged so that their magnetic poles are aligned in the U direction, and two AF magnets 141 arranged diagonally along the V direction are arranged so that their magnetic poles are aligned in the V direction. 8A, 8B, and 9 show examples in which the AF magnets 141 are arranged so that their magnetic poles are aligned in the U direction.

[0078] Here, "magnetic poles lined up" means that paired magnetic poles (north and south poles) are lined up.

[0079] The OIS magnet 142 drives the lens holder 11 in a direction along the XY plane (a direction perpendicular to the optical axis), and together with the OIS coils 23A to 23D, it constitutes the OIS drive unit D1. Note that, since the OIS coils 23A to 23D each have the same configuration, in the following description, the reference characters A, B, C, and D will be omitted unless otherwise specified.

[0080] Four OIS magnets 142 are provided corresponding to the four AF magnets 141. Each of the four OIS magnets 142 is disposed adjacent to a corresponding AF magnet 141 in the Z direction (optical axis direction).

[0081] Each OIS magnet 142 is configured to have a substantially isosceles trapezoidal shape in a plan view, similar to the AF magnet 141. In other words, when placed in the magnet holder 12, the shape of the OIS magnet 142 is the same as the shape of the AF magnet 141 when viewed from the Z direction.

[0082] Here, the term "same shape" includes shapes that are completely identical in size, as well as shapes that have slight dimensional differences due to, for example, manufacturing errors. Furthermore, if there is a slight dimensional difference between the AF magnet 141 and the OIS magnet 142, one of the AF magnet 141 and the OIS magnet 142 may be positioned so as to protrude from the other of the AF magnet 141 and the OIS magnet 142. Furthermore, if the AF magnet 141 and the OIS magnet 142 have completely identical shapes, the AF magnet 141 and the OIS magnet 142 may be positioned with a misalignment that does not affect the operation of the lens driving device 1.

[0083] The OIS magnet 142 has three single-pole magnets. Specifically, the OIS magnet 142 has a first magnet 142A and two second magnets 142B and 142C.

[0084] The first magnet 142A is arranged so that its magnetic poles are aligned in a direction (U direction or V direction) along an XY plane (plane orthogonal to the optical axis) that is orthogonal to the Z direction. Specifically, the first magnet 142A is magnetized so that the inside of the lens driving device 1 is the N pole and the outside of the lens driving device 1 is the S pole. In other words, the first magnet 142A is arranged so that its magnetic poles are aligned in the same direction as the magnetic poles of the AF magnet 141.

[0085] In the explanation of Figure 8 etc., we will explain the OIS magnet 142 in a position where the inside of the lens driving device 1 is the + side of the U direction and the outside of the lens driving device 1 is the - side of the U direction, out of the four OIS magnets 142.

[0086] The two second magnets 142B, 142C are arranged so as to sandwich the magnetic poles of the first magnet 142A in the direction along the plane orthogonal to the optical axis (the U direction in FIG. 8 etc.). Of the two second magnets 142B, 142C, the second magnet 142B located on the negative side of the first magnet 142A in the U direction is magnetized so that the north pole and south pole are aligned in that order from the positive side in the Z direction. Of the two second magnets 142B, 142C, the second magnet 142C located on the positive side of the U direction from the first magnet 142A is magnetized so that the south pole and north pole are aligned in that order from the positive side in the Z direction.

[0087] That is, the two second magnets 142B, 142C are arranged so that their magnetic poles are aligned in the Z direction (optical axis direction) and so that the orientations of the magnetic poles are opposite to each other. In other words, the two second magnets 142B, 142C are arranged so that their magnetic poles are aligned in a direction perpendicular to the direction in which the magnetic poles of the AF magnet 141 are aligned.

[0088] In this way, the first magnet 142A and the two second magnets 142B, 142C are arranged so that the magnetic pole orientation of adjacent magnets in the U direction differs by 90 degrees, thereby magnetizing the OIS magnet 142 in a Halbach array. In other words, the first magnet 142A and the two second magnets 142B, 142C are arranged in the Halbach array so that the magnetic force is stronger on the side facing the OIS coil 23 (the negative side in the Z direction) than on the opposite side (the positive side in the Z direction).

[0089] Also, the second magnet 142B on the negative side in the U direction is located at a position corresponding to the south pole of the AF magnet 141. In other words, the first pole (north pole) of the second magnet 142B facing the AF magnet 141 is located at a position corresponding to a pole (south pole) in the AF magnet 141 that has a different polarity from the first pole.

[0090] The second magnet 142C on the positive side in the U direction is located at a position corresponding to the north pole of the AF magnet 141. In other words, the second pole (south pole) of the second magnet 142C facing the AF magnet 141 is located at a position corresponding to a pole (north pole) having a different polarity from the second pole of the AF magnet 141.

[0091] By arranging the two second magnets 142B and 142C in this manner, each of the second magnets 142B and 142C is magnetically attracted to the AF magnet 141. As a result, the OIS magnet 142 is more easily fixed to the AF magnet 141.

[0092] As shown in FIGS. 9 and 10, the first magnet 142A and the two second magnets 142B and 142C face the first portion 231 and the second portion 232 of the OIS coil 23 in the Z direction.

[0093] First portion 231 is a portion corresponding to the outside of coil substrate 22 of OIS coil 23, which is configured in an annular shape, and is located in a range overlapping with first magnet 142A and second magnet 142B on the negative side in the U direction when viewed from the Z direction. Second portion 232 is a portion corresponding to the inside of coil substrate 22 of OIS coil 23, which is configured in annular shape, and is located in a range overlapping with first magnet 142A and second magnet 142B on the positive side in the U direction when viewed from the Z direction. In other words, OIS coil 23 is located in a range overlapping with the projection plane of OIS magnet 142 in the Z direction.

[0094] Furthermore, the OIS magnet 142 is located on the negative side in the Z direction of the AF coil 13. In other words, the AF coil 13 is located within the range of the AF magnet 141 in the Z direction.

[0095] The cover portion 143 is a member that surrounds the entire driving magnet 14, and is made of, for example, a non-magnetic metal plate (for example, copper). The cover portion 143 has a first portion 143A and a second portion 143B.

[0096] The first portion 143A is a portion disposed on the positive side in the Z direction of the drive magnet 14 (AF magnet 141). The second portion 143B is a portion extending from both sides in the U direction of the first portion 143A to the negative side in the Z direction. Note that, although FIGS. 8A and 8B show a configuration in which the magnetic poles of the AF magnet 141 are aligned in the U direction, if the magnetic poles of the AF magnet 141 are aligned in the V direction, the second portion 143B will be a portion extending from both sides in the V direction of the first portion 143A to the negative side in the Z direction.

[0097] With this configuration, the cover portion 143 is configured so that the two second portions 143B can sandwich the entire drive magnet 14. As a result, the AF magnet 141 and the OIS magnet 142 can be easily fixed.

[0098] The effects of the present embodiment configured as above will be described below. Fig. 11 is a diagram for explaining the flow of magnetic flux in the drive magnet in a conventional example. Fig. 12 is a diagram for explaining the flow of magnetic flux in the drive magnet in this embodiment.

[0099] For example, as in Patent Document 1, when the drive magnet is configured to serve as both an AF magnet and an OIS magnet, one of the AF coil and the OIS coil can be arranged to face the drive magnet in the direction in which the magnetic poles are aligned. Since magnetic flux basically flows in the direction in which the magnetic poles are aligned as a magnetic pole pair of N and S poles, a sufficient amount of magnetic flux flows in one of the coils, making it possible to drive the drive unit corresponding to that coil with sufficient thrust.

[0100] However, the other of the AF coil and OIS coil cannot be positioned facing the drive magnet in the direction in which the magnetic poles are aligned. Therefore, magnetic flux flows from the north pole to the south pole located on the opposite side of the other coil, resulting in a large amount of magnetic flux flowing in a direction different from the direction in which the magnetic poles are aligned. In other words, the amount of magnetic flux flowing in a direction different from the direction in which the magnet faces the other coil is large. Such magnetic flux is difficult to use for the operation of the drive unit.

[0101] 11, in a configuration in which the drive magnet 14 is arranged so that its magnetic poles are aligned in a direction facing the AF coil 13, a sufficient amount of magnetic flux flows from the drive magnet 14 to the AF coil 13 (see arrow B1). However, the OIS coil 23 is arranged in a direction substantially perpendicular to the direction in which the magnetic poles of the drive magnet 14 are aligned. Therefore, magnetic flux (see arrow B2) flows from the north pole of the drive magnet 14 around to the south pole of the drive magnet 14 in the OIS coil 23. As described above, the magnetic flux of arrow B2 is difficult to use for the operation of the OIS drive unit.

[0102] In other words, in a configuration in which the drive magnet serves both as an AF magnet and an OIS magnet, it may be difficult to improve the thrust for either the AF drive or the OIS drive.

[0103] 12, the drive magnet 14 has an AF magnet 141 and an OIS magnet 142. The OIS magnet 142 has a magnet whose magnetic poles are arranged in a direction perpendicular to the direction in which the magnetic poles of the AF magnet 141 are arranged.

[0104] This allows the drive magnet 14 to be positioned so that a sufficient amount of magnetic flux (see arrows B3 and B4) flows from each of the AF magnet 141 and the OIS magnet 142 to both the AF coil 13 and the OIS coil 23.

[0105] As a result, a sufficient amount of magnetic flux can be passed through both the AF coil 13 and the OIS coil 23, thereby improving the thrust for both the AF drive and the OIS drive.

[0106] Furthermore, in the magnet holder 12 that houses the drive magnet 14, the OIS magnet 142 is disposed adjacent to the AF magnet 141, so that the overall configuration can be made compact.

[0107] Furthermore, first magnet 142A and two second magnets 142B, 142C are arranged in a Halbach array so that the magnetic force is stronger on the side facing OIS coil 23 than on the opposite side. As a result, the amount of magnetic flux flowing through OIS coil 23 can be further increased, thereby further improving the thrust force caused by OIS drive. Furthermore, even with a configuration without a first magnet (a configuration with only a second magnet), the magnetic force can be strengthened, but by providing first magnet 142A, the magnetic force on the OIS coil 23 side can be further increased. As a result, the thrust force caused by OIS drive can be significantly improved.

[0108] Furthermore, since the OIS coil 23 is positioned in a range that overlaps with the projection plane of the OIS magnet 142 in the Z direction, the magnetic flux flowing from the OIS magnet 142 can be reliably passed to the OIS coil 23 .

[0109] Incidentally, if the AF magnet and the OIS magnet have different shapes, it is necessary to adjust the magnet holder to match the shape of the larger of the AF magnet and the OIS magnet.

[0110] In contrast, in the present embodiment, the shape of the OIS magnet 142 is the same as that of the AF magnet 141 when viewed from the Z direction in a state in which it is placed in the magnet holder 12. As a result, there is no need to match the magnet holder 12 to the shape of either the AF magnet 141 or the OIS magnet 142, so the shape of the magnet holder 12 can be simplified, and ultimately the overall size can be made compact. Also, it becomes easier to place the AF magnet 141 and the OIS magnet 142 inside the magnet holder 12.

[0111] Furthermore, since the cover portion 143 surrounds the AF magnet 141 and the OIS magnet 142, the AF magnet 141 and the OIS magnet 142 can be easily fixed.

[0112] Furthermore, because OIS magnet 142 is made up of three single-pole magnets, the three single-pole magnets can be sandwiched by cover portion 143. First magnet 142A is sandwiched between second magnets 142B and 142C, but the magnetic pole of first magnet 142A is adjacent to both the north pole and the south pole of second magnets 142B and 142C. Therefore, the magnetic pole of first magnet 142A is magnetically repelled by magnetic poles of the same polarity, which may make it difficult to determine the arrangement of OIS magnet 142.

[0113] In contrast, in this embodiment, the three monopole magnets are sandwiched between the cover portion 143, so that the arrangement of the OIS magnets 142 can be stabilized.

[0114] In the above embodiment, the OIS magnet has the same shape as the AF magnet when viewed in the optical axis direction, but the present invention is not limited to this, and the OIS magnet may have a different shape from the AF magnet.

[0115] Furthermore, in the above embodiment, the number of drive magnets was four, but the present invention is not limited to this, and the number of drive magnets may be any number as long as it is a number appropriate for the configuration of the drive device.

[0116] Furthermore, in the above embodiment, the OIS driving unit drives the lens holder, but the present invention is not limited to this. For example, as shown in FIG. 14, the OIS driving unit may drive the image sensor.

[0117] FIG. 13 shows a simplified cross-sectional view of the lens driving device 1 taken along a plane perpendicular to the U direction.

[0118] The image stabilization method in this configuration is a so-called sensor shift method in which the imaging element is swung. This configuration differs from the configurations shown in Figures 2 to 6 in that the image sensor board 41 and the imaging element 42 are provided on the positive side in the Z direction relative to the base 21.

[0119] The image sensor board 41 is disposed on the negative Z-direction side of the coil board 22 on which the OIS coil 23 is disposed. An opening is formed in the portion of the image sensor board 41 corresponding to the lens housing portion 111, and the image sensor 42 is disposed in the opening. In this configuration, the coil board 22 corresponds to the "image sensor holding portion" of the present invention.

[0120] The image sensor substrate 41 constitutes an OIS movable part that can swing in a plane perpendicular to the optical axis direction. The configuration of the OIS movable part (the configuration that moves the image sensor) can adopt a known sensor shift type configuration, so a description thereof will be omitted.

[0121] Even with this configuration, it is possible to improve the thrust of the drive operations of both the AF drive unit and the OIS drive unit.

[0122] Furthermore, in the above embodiment, the OIS magnet has the same shape as the AF magnet when viewed in the optical axis direction, but the present invention is not limited to this, and the OIS magnet does not have to have the same shape as the AF magnet. However, it is preferable that the OIS magnet is positioned so that it is not located closer to the optical axis (lens holder side) than the AF magnet, so as not to affect the magnetic flux flowing from the AF magnet to the AF coil.

[0123] Furthermore, for example, in the above embodiment, a smartphone, which is a camera-equipped mobile terminal, has been described as an example of a camera-equipped device equipped with a camera module A. However, the present invention can be applied to a camera-equipped device 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, laptop computers, tablet terminals, portable game consoles, web cameras, drones, and camera-equipped in-vehicle devices (e.g., backup monitor devices, drive recorder devices). Transportation equipment includes, for example, automobiles and drones.

[0124] 14A and 14B are diagrams showing an automobile V as a camera-mounted device equipped with an in-vehicle camera module VC (Vehicle Camera). FIG. 14A is a front view of the automobile V, and FIG. 14B is a rear perspective view of the automobile V. The automobile V is equipped with the camera module described in the embodiment as the in-vehicle camera module VC. As shown in FIGS. 14A and 14B, 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.

[0125] Furthermore, the above-described embodiments are merely examples of specific embodiments of the present invention, and the technical scope of the present invention should not be interpreted as being limited by these embodiments. In other words, the present invention can be embodied in various forms without departing from the gist or main features of the present invention. For example, the shapes, sizes, numbers, and materials of the components described in the above-described embodiments are merely examples, and can be modified as appropriate. [Industrial Applicability]

[0126] The drive device according to the present invention is useful as a drive device, camera module, and camera-mounted device that can improve the thrust of the drive operation of both the AF drive unit and the OIS drive unit. [Explanation of symbols]

[0127] 1 Lens drive unit 2 Lens section 11 Lens holder 12 Magnetic holder 13 AF coil 14 Drive magnet 15 Upper elastic support member 16 Lower elastic support member 21 Base 22 Coil substrate 23 OIS coil 24 Suspension wire 141 AF magnet 142 OIS Magnet 142A First Magnet 142B 2nd Magnet 142C Second Magnet 143 Cover part 143A Part 1 143B Part 2 D1 OIS drive unit F1 OIS fixed part M1 OIS moving part S1 OIS support part M Smartphone A Camera module

Claims

1. a lens holder for holding a lens; a magnet holder that surrounds at least a portion of the lens holder and accommodates a magnet portion; a driving unit having the magnet unit and the coil unit; an imaging element holding portion that holds an imaging element facing the lens in the optical axis direction; Equipped with the magnet portion includes an autofocus magnet for driving the lens holder in the optical axis direction, and a shake correction magnet for driving the lens holder or the image sensor holding portion in an optical axis orthogonal direction that is perpendicular to the optical axis direction, the coil unit has an autofocus coil facing the autofocus magnet and a shake correction coil facing the shake correction magnet, the shake correction magnet has a first magnet and a second magnet arranged adjacent to the autofocus magnet in the optical axis direction, the first magnet is arranged so that its magnetic poles are aligned in the same direction as the magnetic poles of the autofocus magnet, The second magnet is The magnet is arranged so that its magnetic poles are aligned in a direction perpendicular to the direction in which the magnetic poles of the autofocus magnet are aligned, At least two of the first magnets are provided so as to sandwich each magnetic pole of the first magnet. Drive unit.

2. The first magnet and the second magnet are arranged in a Halbach array so that the magnetic force on the side facing the shake correction coil is stronger than that on the opposite side. The drive device according to claim 1 .

3. the autofocus magnet, the first magnet, and the second magnet are unipolar magnets; The drive device according to claim 1 .

4. The two second magnets are arranged so that their magnetic poles face in opposite directions. The drive device according to claim 3 .

5. a cover portion that surrounds the autofocus magnet and the shake correction magnet; The drive device according to claim 1 .

6. a shape of the shake correction magnet, when placed in the magnet holder, that is the same as that of the autofocus magnet when viewed from the optical axis direction; The drive device according to claim 1 .

7. Four of the autofocus magnets are arranged to surround the autofocus coil on all sides, Four shake correction magnets are provided corresponding to the four autofocus magnets, respectively. The drive device according to claim 1 .

8. the autofocus coil faces the autofocus magnet in a direction along which the magnetic poles of the autofocus magnet are aligned, the shake correction coil faces the shake correction magnet in a direction along which the magnetic poles of the second magnet are aligned; The drive device according to claim 1 .

9. The drive device according to claim 1 ; an element portion including the lens; an imaging unit including the imaging element that captures a subject image formed by the element unit; Equipped with Camera module.

10. A camera-equipped device that is an information device or a transportation device, The camera module according to claim 9; an imaging control unit that processes image information obtained by the camera module; Equipped with Camera-equipped device.

Images