Optical Element Driving Device, Camera Module, and Camera Mounting Device

Abstract

The present invention relates to an optical element driving device for driving an optical element, a camera module, and a camera mounting device. The optical element driving device includes: a driving unit that drives a holding unit capable of holding an optical element; a substrate having a circuit that includes an inductor for boosting an input voltage to the driving unit; and a metallic cover member having an opening and a flange portion extending along the outer periphery of the opening, and covering the inductor in a state where the inductor is accommodated in the opening and the flange portion is disposed on the substrate. The substrate has a metal layer disposed to face the inductor. The metal layer is formed to include a region where the inductor is disposed in a plan view.

Description

Technical Field

[0001] The present invention relates to an optical element driving device, a camera module, and a camera mounting device for driving an optical element. Background Art

[0002] Generally, a camera module is mounted in a camera mounting device such as a smartphone or a drone. An optical element driving device for driving an optical element is used in such a camera module. It should be noted that a drone is an unmanned aircraft that can fly through remote operation or automatic control, and there is also a drone called a "multi-rotor aircraft".

[0003] The optical element driving device has an autofocus function (hereinafter referred to as "AF function", AF: Auto Focus, autofocus). The optical element driving device moves the lens in the optical axis direction through the AF function and automatically focuses when photographing an object.

[0004] As such an optical element driving device, for example, Patent Document 1 discloses a lens driving device having: an actuator having a piezoelectric element for driving a lens in the optical axis direction; and a circuit for controlling the voltage applied to the piezoelectric element.

[0005] Prior Art Documents

[0006] Patent Documents

[0007] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2020-13065 Summary of the Invention

[0008] Problems to be Solved by the Invention

[0009] As shown in Patent Document 1, in a lens driving device, an actuator having a piezoelectric element is used as a driving source for a lens. Research is being conducted on using an ultrasonic motor that can obtain a large thrust as an actuator.

[0010] In order to drive an ultrasonic motor, a relatively large driving voltage is required. However, in a small and thin camera mounting device, the input voltage from the power supply is relatively small. Therefore, it is configured to use an inductor to boost the input voltage and supply it to the ultrasonic motor.

[0011] In this way, an inductor can boost the input voltage. However, since it has a coil, there is leakage flux from the coil and noise caused by the leakage flux. Therefore, it is configured to cover the inductor with a metal cover mounted by adhesion or the like on the substrate on which the inductor is provided to suppress the leakage flux and noise.

[0012] However, there is a possibility that magnetic flux and noise may leak from the bonding portion between the substrate and the cover or the like. In addition, there is a possibility that magnetic flux and noise may leak from the back side of the substrate in the portion where the inductor is provided. In particular, in the case of using a thin substrate such as a flexible printed circuit board, etc., the possibility of magnetic flux and noise leaking from the back side of the substrate is high.

[0013] An object of the present invention is to provide an optical element driving device, a camera module, and a camera mounting device capable of suppressing leakage of magnetic flux and noise.

[0014] Solution to the problem

[0015] The optical element driving device of the present invention includes:

[0016] A driving unit having a piezoelectric element that drives a holding unit capable of holding an optical element;

[0017] A substrate having a circuit that includes an inductor that boosts the input voltage to the piezoelectric element; and

[0018] A metallic cover member having an opening portion and a flange portion extending along the outer periphery of the opening portion, and covering the inductor in a state where the inductor is accommodated in the opening portion and the flange portion is disposed on the substrate,

[0019] The substrate has a metal layer disposed to face the inductor.

[0020] The camera module of the present invention includes:

[0021] The above-described optical element driving device; and

[0022] An imaging unit that images an object image using the optical element.

[0023] The camera mounting device of the present invention is an information device or a transportation device, and includes:

[0024] The above-described camera module; and

[0025] An image processing unit that processes the image information obtained by the camera module.

[0026] Effect of the invention

[0027] According to the present invention, leakage of magnetic flux and noise can be suppressed. Description of the drawings

[0028] Figure 1A It is a front view of a smartphone equipped with the camera module of the embodiment of the present invention.

[0029] Figure 1B is Figure 1ARear view of the smartphone shown.

[0030] Figure 2 Is a perspective view showing the camera module and the imaging unit.

[0031] Figure 3 Is a top view of the optical element driving device body included in the optical element driving device of the camera module.

[0032] Figure 4 Is showing Figure 3 Top view of the substrate portion of the optical element driving device body shown, and is a view showing the substrate portion developed into a plane.

[0033] Figure 5 Is a view of the optical element driving device body shown when observed from the outside Figure 3 .

[0034] Figure 6 Is a cross-sectional view of the end portion of the substrate portion on which the cover member is mounted.

[0035] Figure 7 Is a view of the accommodation portion of the optical element driving device body shown when observed from the inside Figure 3 .

[0036] Figure 8 Is a cross-sectional view of the insertion portion including the accommodation portion into which the cover member is inserted.

[0037] Figure 9A Is a front view of an automobile showing a camera mounting device on which a vehicle-mounted camera module is mounted.

[0038] Figure 9B Is a perspective view of the automobile shown when observed from the obliquely rear side Figure 9A . Detailed Description of the Invention

[0039] Hereinafter, embodiments of the present invention will be described in detail based on the drawings.

[0040] [Smartphone]

[0041] Figure 1A And Figure 1B Is a view showing a smartphone M (an example of a camera mounting device) on which the camera module A of the present embodiment is mounted. Figure 1A Is a front view of the smartphone M, Figure 1B Is a rear view of the smartphone M.

[0042] The smartphone M has a dual-lens camera composed of two rear cameras OC1 and OC2. In the present embodiment, the camera module A is applied to the rear cameras OC1 and OC2.

[0043] The camera module A has an AF function and can automatically focus when shooting a subject. It should be noted that the camera module A may also have an anti-shake function (hereinafter referred to as the "OIS function", OIS: Optical Image Stabilization), and through the OIS function, it is possible to optically correct the shake (vibration) generated during shooting to capture a non-blurred image.

[0044] [Camera module]

[0045] Figure 2 It is a perspective view showing the camera module A and the imaging unit 5. Figure 3 Is Figure 2 The top view of the optical element driving device main body 4 of the optical element driving device 1 of the camera module A shown. As Figure 2 And Figure 3 Shown, in the present embodiment, an orthogonal coordinate system (X, Y, Z) is used for explanation. In addition, in the figures described later, an orthogonal coordinate system (X, Y, Z) is also used for explanation.

[0046] When the camera module A is used for shooting with a smartphone M, for example, 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 Figure 2 The optical axis direction of the optical axis OA of the lens unit 2 shown, in Figure 2 In, 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 imaging side in the optical axis direction.

[0047] It should be noted that the optical axis OA is used for explanation hereinafter, but for the optical axis direction of the optical axis OA, it can also be referred to as the optical path direction or the focus direction (the direction for adjusting the focus) depending on the type of optical element. Here, the optical path formed by the opening 301 of the cover 3 described later, the opening 11 of the holding portion 10 described later, or the accommodation opening 21 of the accommodation portion 20 described later is the optical path, and the extending direction of this optical path (the direction passing through each opening) is the optical path direction.

[0048] As Figure 2 And Figure 3 Shown, the camera module A includes an optical element driving device 1 for realizing the AF function, a lens unit 2 that accommodates a lens in a cylindrical lens barrel, an imaging unit 5 that images the subject image formed by the lens unit 2, etc. That is, the optical element driving device 1 is a so-called lens driving device that drives the lens unit 2 as an optical element.

[0049] [Cover]

[0050] In the optical element driving device 1, the outside of the optical element driving device main body 4 is covered by a cover 3. The cover 3 is a covered quadrangular cylindrical body having a substantially rectangular shape when viewed from above in the Z direction. In the present embodiment, the cover 3 has a substantially square shape when viewed from above. The cover 3 has a substantially circular opening 301 on its upper surface. The lens unit 2 is configured to be accommodated in the opening 11 of the holding unit 10 of the optical element driving device main body 4, face the outside from the opening 301 of the cover 3, and 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 accommodating portion 20 (bottom 22a) of the optical element driving device main body 4 by adhesion, for example, to accommodate the optical element driving device main body 4.

[0051] The cover 3 has a component that blocks electromagnetic waves from the outside of the optical element driving device 1 or the inside of the cover 3, for example, a shielding component made of a magnetic material.

[0052] [Imaging unit]

[0053] 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 substrate 501, an imaging element 502 mounted on the image sensor substrate 501, and a control unit 503. The imaging element 502 is constituted by, for example, a CCD (charge-coupled device) type image sensor, a CMOS (complementary metal oxide semiconductor) type image sensor, etc., and images an object image formed by the lens unit 2.

[0054] The control unit 503 is constituted by, for example, a control IC, and performs drive control 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. The control unit 503 may be provided on the image sensor substrate 501, or may be provided on a camera mounting device (a smartphone M in the present embodiment) that mounts the camera module A.

[0055] It should be noted that, in Figure 2 , with respect to the image sensor substrate 501 whose position is fixed, the lens unit 2 is driven in the Z direction by the optical element driving device 1, so that the object image is formed on the imaging element 502. However, 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 by driving the imaging element 502 as an optical element in the Z direction by the optical element driving device 1, the object image can be formed on the imaging element 502.

[0056] [Optical element driving device main body]

[0057] The main body 4 of the optical element driving device is the main body part of the optical element driving device 1 that drives the lens part 2, which is an optical element, in the Z direction. It should be noted that hereinafter, for the convenience of explanation, it is assumed that the optical element driving device 1 drives the lens part 2, but as described above, the optical element driving device 1 can also drive the imaging element 502.

[0058] As Figure 3 shown, the main body 4 of the optical element driving device includes: a holding part 10, a housing part 20, support parts 30A, 30B, 30C, driving parts 40A, 40B, and a substrate part 50, etc.

[0059] [Holding Part]

[0060] The holding part 10 has a frame part 12 with an opening 11 formed in the central part, and the opening 11 is configured to be able to hold the lens part 2 inside. For example, the opening 11 is configured to be able to hold the lens part 2 on its inner peripheral surface by forming an installation groove or the like on its inner peripheral surface. In this way, the holding part 10 holds the lens part 2 so as to surround the outer periphery of the lens part 2.

[0061] The outer peripheral side of the frame part 12, that is, the outer peripheral surface 13, is supported by support parts 30A, 30B, 30C extending in the Z direction at multiple positions (three positions as an example in Figure 3 ).

[0062] In addition, multiple positions of the outer peripheral surface 13 (two positions as an example in Figure 3 ) are held by the driving parts 40A, 40B, and the holding part 10 can move in the Z direction due to the driving of the driving parts 40A, 40B.

[0063] In addition, in the outer peripheral surface 13, magnets 14A, 14B for Z-direction position detection are provided at multiple positions (two positions as an example in Figure 3 ). Position detection sensors 54A, 54B described later are respectively provided so as to face the magnets 14A, 14B.

[0064] It should be noted that the opening 11 is formed in a cylindrical shape corresponding to the cylindrical lens part 2, but it can be changed to an appropriate shape corresponding to the shape of the lens part 2.

[0065] In addition, when the optical element driving device 1 drives the imaging element 502, there may be no opening 11 in the holding part 10, that is, the holding part 10 may not be a frame part. In this case, for example, it can be configured to hold the imaging element 502 on the upper surface (the light-receiving side surface) of the holding part 10.

[0066] [Housing Part]

[0067] The accommodating portion 20 has a frame portion 22 with an accommodation opening 21 formed in the central portion. The accommodation opening 21 is configured to surround the outer periphery of the holding portion 10 so that the holding portion 10 can be accommodated therein.

[0068] Support portions 30A, 30B, and 30C are provided at a plurality of positions on the inner peripheral surface 23 inside the accommodation opening 21. The accommodating portion 20 supports the holding portion 10 by the support portions 30A, 30B, and 30C in such a manner that the holding portion 10 can move in the Z direction.

[0069] In addition, drive portions 40A and 40B are provided at a plurality of positions on the inner peripheral surface 23. The drive portions 40A and 40B provided in the accommodating portion 20 move the holding portion 10 in the Z direction. The holding portion 10 functions as a movable portion driven by the drive portions 40A and 40B, and the accommodating portion 20 functions as a fixed portion for the holding portion 10.

[0070] In a plan view, the inner peripheral surface 23 is formed in a shape corresponding to the outer peripheral surface 13 of the holding portion 10. In Figure 3 this case, 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 an example, and can be appropriately changed according to, for example, the arrangement of the support portions 30A, 30B, 30C, the drive portions 40A, 40B, etc.

[0071] The frame portion 22 has a bottom portion 22a and side wall portions 22b. The inner wall of the above-described cover 3 is fixed to the bottom portion 22a, for example, by adhesion. A substrate portion 50 is mounted along the outer peripheral surface 24 on the outer peripheral side of the side wall portion 22b, that is, on the outer peripheral surface 24.

[0072] [Support portion]

[0073] The support portions 30A, 30B, and 30C support the holding portion 10 with respect to the accommodating portion 20 in such a manner that the holding portion 10 can move in the Z direction. As Figure 3 shown, the support portions 30A, 30B, and 30C are respectively arranged at three positions dispersed in the circumferential direction on the inner peripheral surface 23 (outer peripheral surface 13).

[0074] Although detailed illustrations are omitted, the support portions 30A, 30B, and 30C have: a first groove portion provided on the outer peripheral surface 13 of the holding portion 10; a second groove portion provided on the inner peripheral surface 23 of the accommodating portion 20; and a rolling member (for example, a ball member, etc.) that is clamped between the first groove portion and the second groove portion and can roll.

[0075] In the support portions 30A, 30B, and 30C, the first groove portion and the second groove portion are arranged to extend in the Z direction and face each other. Between the first groove portion and the second groove portion arranged in this way, the rolling member is clamped in a manner that it can roll.

[0076] One or more rolling members are disposed between the first groove portion and the second groove portion. When a plurality of rolling members are disposed between the first groove portion and the second groove portion, the tilt of the holding portion 10 can be more stably suppressed. In this case, the plurality of rolling members are arranged in the Z direction and are held by a seat ring (not shown) so that the mutual distance is kept constant and positioning in the Z direction can be performed.

[0077] With the support portions 30A, 30B, and 30C configured in this way, the holding portion 10 is supported relative to the housing portion 20 so as to be movable in the Z direction.

[0078] It should be noted that guide rail-like members made of a metal material or the like and capable of allowing the rolling members to roll may be provided in the first groove portion and the second groove portion. The holding portion 10 and the housing portion 20 are usually made of resin or the like, and the rolling members are usually made of materials such as ceramics or alloys. Therefore, by providing guide rail-like members made of a metal material or the like harder than the holding portion 10 and the housing portion 20 in the first groove portion and the second groove portion, the first groove portion and the second groove portion are not easily deformed even when pressed by the rolling members. With such a structure, the support portions 30A, 30B, and 30C can stably support the holding portion 10 so as to be movable in the Z direction.

[0079] [Drive section]

[0080] The drive portions 40A and 40B drive the holding portion 10 in the Z direction relative to the housing portion 20. As Figure 3 shown, the drive portions 40A and 40B are respectively disposed at two positions dispersed in the circumferential direction on the inner peripheral surface 23 (outer peripheral surface 13). The optical element drive device main body 4 can drive the lens portion 2 and the holding portion 10 together in the Z direction by using the support portions 30A, 30B, and 30C and the drive portions 40A and 40B described above, thereby realizing the AF function.

[0081] In Figure 3 the example shown, the drive portions 40A and 40B are respectively disposed at corner portions 22bB and 22bC different from the corner portion 22bA where the support portion 30A is disposed and are corner portions that are point-symmetrical with respect to the optical axis OA in a top view. By disposing them in this way, even if the weight of the optical element such as the lens portion 2 increases, the holding portion 10 can be stably moved.

[0082] As the drive portions 40A and 40B, an actuator having a piezoelectric element, for example, an ultrasonic motor, is used. It should be noted that a drive source such as a voice coil motor (VCM) may also be used.

[0083] [Substrate section]

[0084] Together with Figure 3 also refer to Figure 4 and Figure 5 to describe the substrate portion 50. Figure 4 It is a top view of the substrate portion 50 of the optical element driving device main body 4 shown in Figure 3 and is a view in which the substrate portion 50 is developed into a plane. Figure 5 It is a view of the optical element driving device main body 4 shown in Figure 3 viewed from the outside, and is a view observed from the direction D1 shown in Figure 3 . It should be noted that the driving portions 40A and 40B are not mounted on the FPC 51 of the substrate portion 50. However, in Figure 4 , the driving portions 40A and 40B are shown for easy understanding of the positional relationship.

[0085] The substrate portion 50 has a circuit for driving the driving portions 40A and 40B. The substrate portion 50 includes: an FPC (Flexible Printed Circuit; flexible printed circuit) 51, a driver IC 52, inductors 53A and 53B, and position detection sensors 54A and 54B, etc.

[0086] The FPC 51 is a flexible substrate formed by laminating a thin insulating layer such as a resin film and a metal layer such as a copper foil. Although not shown, the metal layer forms circuits for signal lines and power supply lines, and electrically connects the driving portions 40A and 40B, the driver IC 52, the inductors 53A and 53B, the position detection sensors 54A and 54B, etc.

[0087] The driver IC 52 is an IC that controls the driving signals for driving the driving portions 40A and 40B. The driver IC 52 outputs a driving signal based on, for example, the detection signals detected by the position detection sensors 54A and 54B, and the output driving signal is output to the driving portions 40A and 40B via the inductors 53A and 53B.

[0088] Each of the inductors 53A and 53B has a coil, and boosts the voltage (input voltage) in the driving signal input from the driver IC 52 and outputs it to the driving portions 40A and 40B, respectively.

[0089] The position detection sensors 54A and 54B are, for example, magnetic sensors such as Hall elements, and output signals corresponding to the positions in the Z direction of the magnets 14A and 14B arranged opposite to each other (the intensities of the magnetic fields of the magnets 14A and 14B) as detection signals.

[0090] It should be noted that although not shown, connection wirings electrically connected to the driving portions 40A and 40B are provided in the FPC 51.

[0091] In order to mount the above-described driver IC 52, inductors 53A and 53B, and position detection sensors 54A and 54B on the FPC 51, the FPC 51 is provided as a single long substrate. Moreover, the FPC 51 is arranged along the outer peripheral surface 24 of the frame portion 22 of the housing portion 20 so as to go around the outer peripheral surface 24 substantially once.

[0092] In order to arrange the FPC 51 along the outer peripheral surface 24, the outer peripheral surfaces 24 of the portions of the corner portions 22bA, 22bB, and 22bC are formed in an arc shape in a plan view. As a result, the outer peripheral surface 24 including the portions of the corner portions 22bA, 22bB, and 22bC can be included, and the FPC 51 can be arranged in close contact with the outer peripheral surface 24. Therefore, it is not necessary to increase the size of the cover 3 arranged outside the FPC 51, the miniaturization of the entire device can be achieved, and the cost reduction can be achieved.

[0093] In addition, the FPC 51 has: an FPC main portion 51a, FPC narrow portions 51b and 51c, and FPC end portions 51d and 51e. The FPC main portion 51a connects the FPC narrow portion 51b and the FPC end portion 51d on one end side in the length direction to the FPC narrow portion 51c and the FPC end portion 51e on the other end side, and the driver IC 52, and the position detection sensors 54A and 54B are mounted thereon.

[0094] The FPC narrow portions 51b and 51c are portions where the width in the direction orthogonal to the length direction becomes narrower, respectively, between the FPC main portion 51a and the FPC end portion 51d, and between the FPC main portion 51a and the FPC end portion 51e. As shown in Figure 5 The FPC narrow portions 51b and 51c are formed so as to avoid the portions of the arrangement support portions 30B and 30C of the housing portion 20. By providing such FPC narrow portions 51b and 51c, it is not necessary to increase the size of the cover 3 arranged outside the FPC 51, the miniaturization of the entire device can be achieved, and the cost reduction can be achieved.

[0095] At the FPC end portions 51d and 51e, which are the both end portions in the length direction of the FPC 51, the inductors 53A and 53B are respectively mounted. As described above, the inductors 53A and 53B have coils, and there are leakage fluxes and noise emissions from the coils. The leakage fluxes and noise emissions may affect the position detection sensors 54A and 54B. Therefore, in order to ensure the distance from the position detection sensors 54A and 54B, the inductors 53A and 53B are arranged at the FPC end portions 51d and 51e. On the other hand, for position detection, the position detection sensors 54A and 54B are arranged at positions close to the drive portions 40A and 40B where the driving force acts.

[0096] Furthermore, in the present embodiment, in order to suppress the leakage fluxes and noise, the following structure is provided. Here,Figure 6 A cross-sectional view of the FPC end portion 51d of the substrate portion 50 on which the cover member 60A is mounted, and it is Figure 4 a cross-sectional view taken along the arrow D3 - D3 shown. It should be noted that in Figure 6 , the structure of the cover member 60A and its surroundings is illustrated, but the structure of the cover member 60B and its surroundings is also the same structure.

[0097] In the present embodiment, in order to suppress leakage magnetic flux and noise, the optical element driving device main body 4 includes cover members 60A, 60B and a metal layer 55.

[0098] The cover members 60A, 60B are formed of a metallic material that shields leakage magnetic flux and noise. As Figures 4 to 6 shown, the cover members 60A, 60B have a lid portion 61, an opening portion 62, a flange portion 63, etc.

[0099] The lid portion 61 is a covered quadrangular cylindrical body having an opening portion 62. The flange portion 63 extends along the outer periphery of the opening portion 62. Specifically, the flange portion 63 extends along the surface of the FPC end portions 51d, 51e on the outer periphery of the edge 61a of the lid portion 61 which is the outer peripheral portion of the opening portion 62.

[0100] Moreover, the cover members 60A, 60B are configured to accommodate the inductors 53A, 53B mounted on the FPC end portions 51d, 51e in the opening portion 62, and cover the inductors 53A, 53B in a state where the flange portion 63 is disposed on the FPC end portions 51d, 51e.

[0101] In this way, the cover members 60A, 60B have not only the lid portion 61 but also the flange portion 63. Therefore, the leakage magnetic flux and noise radiated from the inductors 53A, 53B toward the cover members 60A, 60B can be shielded in a wider range by the lid portion 61 and the flange portion 63. As a result, compared with the cover member without the flange portion, the magnetic flux and noise leaking to the outside can be further reduced.

[0102] For example, the flange portion 63 can also be fixed to the surface of the FPC end portions 51d, 51e using an adhesive or the like. Compared with the case without the flange portion, the contact area between the flange portion 63 and the surface of the FPC end portions 51d, 51e becomes wider. Therefore, the cover members 60A, 60B can be reliably fixed to the surface of the FPC end portions 51d, 51e.

[0103] As Figure 6As shown, at the end portion 51d of the FPC, the metal layer 55 is arranged so as to face the inductor 53A mounted on the end portion 51d of the FPC. The metal layer 55 is provided, for example, on the surface of the end portion 51d of the FPC on the side opposite to the surface on which the inductor 53A is mounted. Moreover, the metal layer 55 is formed of a solid pattern that at least includes the region where the inductor 53A is arranged in a plan view.

[0104] Thus, since the metal layer 55 is provided at the end portion 51d of the FPC where the inductor 53A is mounted, the leakage magnetic flux and noise radiated from the inductor 53A toward the end portion 51d side of the FPC can be shielded by the metal layer 55. As a result, compared with the FPC without the above metal layer 55, the magnetic flux and noise leaking to the outside through the FPC51 can be reduced.

[0105] Furthermore, it is preferable that Figure 4 , Figure 6 as shown, the metal layer 55 is formed so as to overlap with the flange portion 63. As a result, the gap g between the flange portion 63 and the metal layer 55 can be reduced. This is particularly effective when the FPC is used as a substrate.

[0106] Thus, since the gap g between the flange portion 63 and the metal layer 55 is reduced, substantially all of the periphery of the inductor 53A can be covered by the cover member 60A and the metal layer 55. Accordingly, the leakage magnetic flux and noise radiated from the inductor 53A can be shielded by the cover member 60A and the metal layer 55. As a result, the magnetic flux and noise leaking to the outside can be further reduced.

[0107] The cover members 60A and 60B are made of a metal material that reduces leakage magnetic flux and noise. As the cover members 60A and 60B, for example, a laminated structure is used, which is a structure in which at least a layer made of iron such as SPCC (Steel Plate Cold Commercial) as a ferromagnetic material is laminated with a layer made of copper and nickel. In this laminated structure, the iron layer, the copper layer, and the nickel layer are laminated in this order, thereby preventing the iron layer from rusting.

[0108] The copper layer is also laminated for the purpose of offsetting the influence of the iron layer on increasing the inductance. By making the copper layer thicker than the nickel layer, the shielding property against noise can also be improved. Thus, in the laminated structure in which at least the iron layer, the copper layer, and the nickel layer are laminated as the cover members 60A and 60B, a structure in which the copper layer is thicker than the nickel layer is more preferable.

[0109] In addition, for the metal layer 55, a power supply layer or a ground layer for supplying power can also be used in the circuit of the FPC 51. In addition, the metal layer 55 is not limited to one layer, and may be composed of a plurality of layers laminated with an insulating layer therebetween. For example, in the case of being composed of two layers laminated with an insulating layer therebetween, one layer may be set as the above-mentioned power supply layer, and the other layer may be used as the ground layer.

[0110] In addition, in the case where the power supply layer or the ground layer of the circuit of the FPC 51 is not used as the metal layer 55, a plurality of metal layers can be laminated to form the metal layer 55 in the same manner as the cover members 60A and 60B.

[0111] Here, Figure 7 is a view of the housing portion 20 of the optical element driving device main body 4 as viewed from the inside, and is a view as viewed from the direction D2 shown in the state where the lens portion 2 and the holding portion 10 are removed. In addition, Figure 3 is a view as viewed from the direction D2 shown in the state where the lens portion 2 and the holding portion 10 are removed. In addition, Figure 3 is a sectional view including the insertion portions 25A and 25B of the housing portion 20 into which the cover members 60A and 60B are inserted. Figure 8 is a sectional view including the insertion portions 25A and 25B of the housing portion 20 into which the cover members 60A and 60B are inserted.

[0112] In order to miniaturize the device, the housing portion 20 has insertion portions 25A and 25B into which the cover members 60A and 60B having the above structure are inserted. As Figure 7 shown, the insertion portions 25A and 25B are provided through the side wall portions 22b of the frame portion 22. However, as long as the cover members 60A and 60B can be inserted, it may be a structure such as a concave portion that does not penetrate the side wall portions 22b.

[0113] By inserting the cover members 60A and 60B into the insertion portions 25A and 25B in this way, miniaturization of the entire device can be achieved, and cost reduction can be achieved.

[0114] In addition, in the case of the structure shown in Figure 8 if the housing portion 20 and the FPC end portion 51d are fixed using an adhesive or the like, the flange portion 63 is fixed between the housing portion 20 and the FPC 51. Therefore, the flange portion 63 may not be fixed to the surfaces of the FPC end portions 51d and 51e. Thereby, the manufacturing process of the optical element driving device main body 4 can be simplified.

[0115] In addition, when the cover members 60A and 60B are inserted in a manner that fits into the insertion portions 25A and 25B, the cover members 60A and 60B also function to reinforce the housing portion 20 having the insertion portions 25A and 25B, and deformation of the housing portion 20 can be suppressed.

[0116] [Other Embodiments]

[0117] The present invention is not limited to the above-described embodiments and can be modified without departing from the gist thereof.

[0118] For example, in the above-described embodiment, the support portions 30A, 30B, and 30C are configured to have the same structure. However, a biasing member may be provided in one or more of these support portions, and the biasing member applies a pressing force to the rolling member to press the outer peripheral surface 13 of the holding portion 10 inward. By providing such a biasing member, tilting of the holding portion 10 can be suppressed.

[0119] Here, as Figure 3 shown, the frame portion 22 of the accommodating portion 20 has four corner portions 22bA, 22bB, 22bC, and 22bD. In a plan view, the corner portions 22bA, 22bB, 22bC, and 22bD have spaces, and since the support portion having the biasing member requires space, the support portion is disposed in at least one of the corner portions 22bA, 22bB, 22bC, and 22bD.

[0120] For example, in the Figure 3 example shown, the above-described biasing member is provided in the support portion 30A, and the support portion 30A is disposed in the corner portion 22bA. By configuring in this way, space saving of the device can be achieved, miniaturization of the entire device can be achieved, and cost reduction can be achieved.

[0121] In addition, it may be configured such that in one or more of these support portions, the rolling member in the groove can be displaced in the circumferential direction. For example, in Figure 3 , the first groove portion and the second groove portion are formed as V-shaped grooves in a plan view, but at least one of these groove portions may be formed as a U-shaped groove having a width wider than the diameter of the rolling member.

[0122] By forming such a U-shaped groove, the rolling member in the groove can be displaced in the circumferential direction, and the outer peripheral surface 13 of the holding portion 10 and the inner peripheral surface 23 of the accommodating portion 20 facing each other can be relatively displaced. With the support portion configured in this way, even if there are individual differences in the dimensions of the holding portion 10, the accommodating portion 20, etc., or individual differences in the state after assembling these parts, the individual differences can be absorbed.

[0123] Furthermore, in the case where one or more of the support portions have the above-described biasing member, in the support portion having the above-described U-shaped groove, the outer peripheral surface 13 of the holding portion 10 and the inner peripheral surface 23 of the accommodating portion 20 are relatively displaced so that the force pressing the rolling member due to the pressing force of the biasing member and its reaction force are balanced. As a result, in the circumferential direction of the holding portion 10, the support position of the holding portion 10 is determined, and stable support without wobbling can be achieved by the above-described plurality of support portions.

[0124] In Figure 3 In the example shown, it is only necessary to have the above U-shaped groove structure in the support portion 30B disposed at a portion of the side between the corner portions 22bB and 22bD and the support portion 30C disposed at a portion of the side between the corner portions 22bC and 22bD. In this case, since the support portions having U-shaped grooves that do not require space are disposed at the side portions avoiding the corner portions 22bA, 22bB, 22bC, and 22bD, the drive portions 40A and 40B that require space can be disposed at the corner portions 22bB and 22bC.

[0125] In addition, in the above-described embodiment, two position detection sensors 54A and 54B are provided. However, the position detection sensor may be one. In this case, it is preferable to provide the position detection sensor near the support portion having a structure in which the rolling member is clamped by the V-shaped groove (in other words, the support portion that does not have the above-described biasing member and U-shaped groove). For example, in Figure 3 when the support portion 30A has a biasing member, the support portion 30B has a U-shaped groove, and the support portion 30C has a structure in which the rolling member is clamped by the V-shaped groove, the support portion 30C is a reference (rotation center) of the holding portion 10 that can be displaced relative to the accommodating portion 20. Therefore, it is sufficient to have one position detection sensor 54B near the support portion 30C that becomes such a reference.

[0126] In addition, regarding the angles between the support portions 30A, 30B, and 30C, it is preferable to arrange them at 120° intervals, but this angle can be appropriately changed. When the support portions 30A, 30B, and 30C are arranged at an angle other than 120° intervals, it is preferable to adopt the following structure and arrangement.

[0127] For example, a biasing member is provided in the support portion 30A, and in one of the support portions 30B and 30C, one of the first groove portion 15 and the second groove portion 26 is set as a U-shaped groove. Moreover, when viewed from above, the pressing direction of the biasing member of the support portion 30A against the rolling member is set to the direction toward the optical axis OA, and the support portion 30B and the support portion 30C are arranged at positions line-symmetric with respect to this direction. By adopting such a structure and arrangement, the pressing forces received from the support portion 30A side in the support portions 30B and 30C are equal, and the holding portion 10 can be stably supported.

[0128] In addition, the support portions may be dispersedly arranged at three or more positions in the circumferential direction of the inner peripheral surface 23 (outer peripheral surface 13). In this case, for the purpose of further supporting between the three-point supports on the basis of the three-point support that can stably support the object, it is preferable to arrange the support portions at positions that are multiples of 3, such as 6 positions and 9 positions.

[0129] In addition, in the above-described embodiment, the smartphone M has been taken as an example for explanation. However, the present invention can be applied to a camera-mounted device having a camera module and an image processing unit, which processes image information obtained by the camera module. The camera-mounted device includes an information device and a transportation device. The information device includes, for example, a portable telephone with a camera, a laptop computer, a tablet terminal, a portable game machine, a web camera, a vehicle-mounted device with a camera (e.g., a rear monitoring device, a dash cam device), etc. In addition, the transportation device includes, for example, an automobile and a drone, etc.

[0130] Figure 9A 、 Figure 9B FIG. is a view showing an automobile V as a camera-mounted device equipped with a vehicle-mounted camera module VC (Vehicle Camera). Figure 9A is a front view of the automobile V, Figure 9B 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 vehicle-mounted camera module VC. As Figure 9A 、 Figure 9B shown, the vehicle-mounted camera module VC is, for example, mounted on the windshield facing forward or on the tailgate facing rearward. The vehicle-mounted camera module VC is used as a vehicle-mounted camera module for rear monitoring, dash cam, collision avoidance control, autonomous driving control, etc.

[0131] In addition, in the above-described embodiment, the optical element driving device 1 that drives the lens unit 2 as an optical element has been described. However, the optical element to be driven may also be an optical element other than a lens, such as a mirror or a prism, or may be an optical element such as an imaging element 502. In this case, the opening 11 of the holding unit 10 may change its shape according to the shape of the optical element to be installed, and the opening may not be provided depending on the situation.

[0132] In addition, in the above-described embodiment, the optical element driving device 1 has an AF function. However, not only the AF function, but also a function such as a zoom function that moves the lens unit 2 in the Z direction may be provided.

[0133] The embodiments of the present invention have been described above. It should be noted 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. That is, the description of the structure of the above device and the shape of each part is an example. Of course, various changes or additions can be made to these examples within the scope of the present invention.

[0134] Industrial Applicability

[0135] The optical element driving device and camera module of the present invention are useful, for example, in camera-equipped devices such as smartphones, mobile phones, digital cameras, laptop computers, tablet terminals, portable game machines, in-vehicle cameras, and drones.

[0136] Description of Reference Numerals

[0137] 1 Optical element driving device

[0138] 2 Lens unit

[0139] 3 Cover

[0140] 4 Optical element driving device main body

[0141] 5 Imaging unit

[0142] 10 Holding part

[0143] 11 Opening

[0144] 12 Frame part

[0145] 13 Outer peripheral surface

[0146] 14A, 14B Magnets

[0147] 20 Accommodating part

[0148] 21 Accommodating opening

[0149] 22 Frame part

[0150] 22a Bottom

[0151] 22b Side wall part

[0152] 22bA, 22bB, 22bC, 22bD Corners

[0153] 23 Inner peripheral surface

[0154] 24 Outer peripheral surface

[0155] 25A, 25B Insertion parts

[0156] 30A, 30B, 30C Support parts

[0157] 40A, 40B Driving parts

[0158] 50 Substrate part

[0159] 51 FPC

[0160] 51a FPC main part

[0161] 51b, 51c FPC narrow parts

[0162] 51d and 51e FPC ends

[0163] 52 Driver IC

[0164] 53A and 53B Inductors

[0165] 54A and 54B Position Detection Sensors

[0166] 55 Metal Layer

[0167] 60A and 60B Cover Parts

[0168] 61 Cover

[0169] 61a Edge

[0170] 62 Opening

[0171] 63 Flange

[0172] 301 Opening

[0173] 501 Image Sensor Substrate

[0174] 502 Imaging Element

[0175] 503 Control Unit

Claims

1. An optical element driving device, characterized in that, it includes: a driving unit having a piezoelectric element for driving a holding unit capable of holding an optical element; a housing unit that houses the holding unit inside in a manner that enables the holding unit to move; a substrate having a circuit and a metal layer, the circuit including an inductor for boosting the input voltage to the piezoelectric element, and the metal layer being disposed opposite to the inductor; and a metallic cover member having a cover portion and a flange portion extending along the outer periphery of the opening portion of the cover portion, and covering the inductor in a state where the inductor is housed in the opening portion and the flange portion is disposed on the substrate; the housing unit has an insertion portion for inserting the cover portion from the outside of the housing unit.

2. The optical element driving device according to claim 1, wherein, the flange portion is sandwiched and fixed between opposed portions of the housing unit and the substrate.

3. The optical element driving device according to claim 2, wherein, the housing unit and the substrate are bonded to each other at positions where the flange portion is not clamped.

4. The optical element driving device according to claim 1, wherein, the cover portion is fitted with the insertion portion.

5. The optical element driving device according to claim 1, wherein, the metal layer is formed to include the region where the inductor is disposed when viewed from above in a plan view from the direction opposite to the inductor.

6. The optical element driving device according to claim 5, wherein, the metal layer is formed to overlap the flange portion when viewed from above in a plan view from the direction opposite to the inductor.

7. The optical element driving device according to claim 1, wherein, the metal layer is a power supply layer or a ground layer for supplying power in the circuit.

8. The optical element driving device according to claim 1, wherein, the cover member is constituted by a laminated structure in which at least an iron layer, a copper layer, and a nickel layer are laminated, and the copper layer is thicker than the nickel layer.

9. A camera module, characterized in that, it includes: the optical element driving device according to any one of claims 1 to 8; and a photographing unit that photographs an object image using the optical element.

10. A camera mounting device, which is an information device or a transportation device, the camera mounting device is characterized in that it includes: the camera module according to claim 9; and an image processing unit that processes the image information obtained by the camera module.

Images