Drive device, optical element drive device, camera module, and camera mounting device

Abstract

The invention provides a driving device, an optical element driving device, a camera module and a camera-mounted device, which can reduce the driving sound between parts when a piezoelectric element is used for driving. The drive device is provided with: a resonance unit that has a pair of arm sections and resonates with the vibration of the piezoelectric element; and a moving part that comes into contact with the pair of arm parts and moves relative to the resonance part in accordance with the vibration of the resonance part, in the resonance part and the moving part, the portions that come into contact with each other are each made of ceramic, and the pair of arm parts have balls made of ceramic as the portions that come into contact with the moving part.

Description

Technical Field

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

[0002] In camera modules mounted on camera-mounted devices such as smartphones and drones, driving devices such as ultrasonic motors using piezoelectric elements have been proposed as driving devices for driving optical elements.

[0003] For example, Patent Document 1 discloses a driving device including a bending displacement member using a piezoelectric element, a friction member provided at a free end of the bending displacement member, and a driven body that contacts the friction member via a preload mechanism. In this driving device, the friction member and the driven body contact each other via the preload mechanism, and when the bending displacement member (piezoelectric element) is driven by voltage application to cause the bending displacement member to bend and displace (vibrate), the driven body moves due to the friction force between the friction member and the driven body.

[0004] Patent Document 1: Japanese Patent Application Publication No. 2010-63349 Summary of the invention

[0005] As shown in Patent Document 1, in a driving device driven by a piezoelectric element, a friction member is in frictional contact with a driven body, and the driven body moves. Therefore, there is a problem that the driving sound generated by the frictionally contacting members is louder than that of other driving devices, such as a driving device using a voice coil motor.

[0006] An object of the present invention is to provide a driving device, an optical element driving device, a camera module, and a camera-mounted device that can reduce driving noise between components when driving using a piezoelectric element.

[0007] The driving device of the present invention comprises:

[0008] a resonating portion having a pair of arm portions and resonating with the vibration of the piezoelectric element; and

[0009] a moving portion that contacts the pair of arm portions and moves relative to the resonating portion as the resonating portion vibrates,

[0010] In the resonating part and the moving part, the mutually contacting parts are respectively made of ceramics.

[0011] The pair of arm portions have spheres made of ceramic as portions that come into contact with the moving portion.

[0012] The optical element driving device of the present invention comprises:

[0013] a holding portion capable of holding the optical element;

[0014] a housing portion for housing the holding portion so as to be movable in the optical path direction of the optical element; and

[0015] A driving device drives the holding portion.

[0016] The camera module of the present invention has:

[0017] The optical element driving device; and

[0018] The imaging unit uses the optical element to capture an image of a subject.

[0019] The camera-mounted device of the present invention is an information device or a transportation device, and the camera-mounted device comprises:

[0020] the camera module; and

[0021] An image processing unit processes the image information obtained by the camera module.

[0022] According to the present invention, it is possible to reduce driving noise between components when driving using a piezoelectric element. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1A It is a front view showing a smartphone equipped with the camera module according to the embodiment of the present invention.

[0024] Figure 1B yes Figure 1A Rear view of the smartphone shown.

[0025] Figure 2 It is a perspective view showing a camera module and an imaging unit.

[0026] Figure 3 It is a plan view of an optical element driving device main body included in the optical element driving device of the camera module.

[0027] Figure 4A Yes Description Figure 3 A diagram of the driving portion of the optical element driving device main body is shown.

[0028] Figure 4B Viewed from the upper side in the Z direction Figure 4A The driving section is shown in FIG.

[0029] Figure 5A The figure is a front view showing a vehicle as a camera mounting device equipped with a vehicle-mounted camera module.

[0030] Figure 5B Observed from the rear side Figure 5A A perspective view of the car shown. DETAILED DESCRIPTION

[0031] Hereinafter, embodiments of the present invention will be described based on the drawings.

[0032] [Smartphone]

[0033] Figure 1A and Figure 1B 1 is a diagram showing a smartphone M (an example of a camera-mounted device) equipped with a camera module A according to the present embodiment. Figure 1A is the main view of smartphone M, Figure 1B is a rear view of the smartphone M.

[0034] The smartphone M has a dual camera including two rear cameras OC1 and OC2. In the present embodiment, the camera module A is applied to the rear cameras OC1 and OC2.

[0035] The camera module A has an AF function, which can automatically focus when photographing a subject. In addition, the camera module A can also have a shake correction function (hereinafter referred to as "OIS function", OIS: Optical Image Stabilization). The OIS function can optically correct the shake (vibration) generated during shooting and shoot an image without image shake.

[0036] [Camera module]

[0037] Figure 2 It is a perspective view showing the camera module A and the imaging unit 5 . Figure 3 yes Figure 2 FIG. 1 is a plan view of an optical element driving device body 4 of an optical element driving device 1 of a camera module A. Figure 2 and Figure 3 As shown, in this embodiment, the orthogonal coordinate system (X, Y, Z) is used for description. In addition, in the following drawings, the orthogonal coordinate system (X, Y, Z) is also used for description.

[0038] For example, when the camera module A is used to take a picture by a smartphone M, the X direction is mounted so that the vertical direction (or horizontal direction), the Y direction is the horizontal direction (or vertical direction), and the Z direction is the front-back direction. Figure 2 The optical axis direction of the optical axis OA of the lens portion 2 shown in FIG. Figure 2 In the figure, the upper side (+Z side) 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.

[0039] In addition, the optical axis OA is used for the following description, but the optical axis direction of the optical axis OA may be referred to as the optical path direction or the focus direction (the direction for adjusting the focus) according to the type of the optical element. Here, the passage of light formed by the opening 301 of the cover 3 described later, the opening 11 of the holding portion 10 described later, or the storage opening 21 of the storage portion 20 described later is the optical path, and the extension direction of the optical path (the penetration direction of each opening) is the optical path direction.

[0040] like Figure 2 and Figure 3 As shown, the camera module A includes an optical element driving device 1 for realizing an AF function, a lens unit 2 formed by accommodating a lens in a cylindrical lens barrel, and a photographing unit 5 for photographing a subject image formed by the lens unit 2. That is, the optical element driving device 1 is a so-called lens driving device for driving the lens unit 2 as an optical element.

[0041] The optical element driving device 1 of this embodiment is considered to be mounted on the camera module A described above, and has a structure in which the length in the Z direction is shorter than the lengths in the X and Y directions. If the Z direction is set as the height direction, it is a thin structure.

[0042] [cover]

[0043] In the optical element driving device 1, the outer side of the optical element driving device body 4 is covered by a cover 3. The cover 3 is a covered quadrangular cylindrical body that is roughly rectangular in shape when viewed from the Z direction. In the present embodiment, the cover 3 has a roughly square shape when viewed from above. The cover 3 has a roughly circular opening 301 on the upper surface. The lens portion 2 is configured such that the opening 11 of the holding portion 10 housed in the optical element driving device body 4 faces the outside from the opening 301 of the cover 3, and protrudes toward the light receiving side more than 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 storage portion 20 (for example, the bottom 22a described later) of the optical element driving device body 4 by, for example, bonding, and houses the optical element driving device body 4.

[0044] The cover 3 includes a member for shielding electromagnetic waves from the outside of the optical element driving device 1 and the inside of the cover 3 , for example, a shielding member made of a magnetic body.

[0045] [Photography Department]

[0046] The imaging unit 5 is arranged on the imaging side of the optical element driving device 1. The imaging unit 5 includes, 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 composed of, for example, a CCD (charge-coupled device) type image sensor, a CMOS (complementary metal oxide semiconductor) type image sensor, etc., and captures the subject image formed by the lens unit 2.

[0047] The control unit 503 is composed of, for example, a control IC, and performs overall 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 can be provided on the image sensor substrate 501, or on a camera-mounted device (a smartphone M in this embodiment) that is equipped with the camera module A.

[0048] In addition, Figure 2 In the embodiment, the lens unit 2 is driven in the Z direction by the optical element driving device 1 relative to the image sensor substrate 501 whose position is fixed, thereby forming a subject image 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 the imaging element 502 as an optical element is driven in the Z direction by the optical element driving device 1, thereby forming a subject image on the imaging element 502.

[0049] [Optical element drive device main body]

[0050] The optical element driving device body 4 is a main part of the optical element driving device 1 that drives the lens unit 2 as an optical element in the Z direction. In addition, for the sake of convenience, the following description is based on the premise that the optical element driving device 1 drives the lens unit 2, but as mentioned above, the optical element driving device 1 can also drive the imaging element 502.

[0051] like Figure 3 As shown, the optical element driving device main body 4 includes a holding portion 10 , a storage portion 20 , support portions 30A, 30B, and 30C, driving portions 40A and 40B, a substrate portion 50 , and the like.

[0052] [Maintenance Department]

[0053] The holding portion 10 has a frame portion 12 having an opening portion 11 formed in the center, and the opening portion 11 is configured to hold the lens portion 2 inside. For example, the opening portion 11 is configured to hold the lens portion 2 on the inner peripheral surface by forming a mounting groove or the like on the inner peripheral surface thereof. In this way, the holding portion 10 surrounds the outer periphery of the lens portion 2 and holds the lens portion 2.

[0054] The outer peripheral surface 13 of the frame 12 has a plurality of locations (in Figure 3 In the embodiment, three locations are provided as an example, and the support parts 30A, 30B, and 30C extending along the Z direction are supported so as to be movable in the Z direction.

[0055] In addition, multiple locations of the outer peripheral surface 13 (in Figure 3 In the embodiment, two parts are used as an example) and the holding part 10 is held by the drive parts 40A and 40B, and the holding part 10 can be moved in the Z direction by the drive parts 40A and 40B.

[0056] In addition, at multiple locations on the outer peripheral surface 13 (in Figure 3 In the embodiment, magnets 14A and 14B for detecting the position in the Z direction are provided at two locations as an example. Position detection sensors 54A and 54B described later are provided respectively in a manner opposing the magnets 14A and 14B.

[0057] In addition, the opening 11 is formed in a cylindrical shape corresponding to the cylindrical lens portion 2 , but can be changed to an appropriate shape corresponding to the shape of the lens portion 2 .

[0058] In addition, when the optical element driving device 1 drives the imaging element 502, the holding portion 10 may not have the opening portion 11, that is, the holding portion 10 may not be a frame portion. In this case, for example, the imaging element 502 can be held on the upper surface (the surface on the light receiving side) of the holding portion 10.

[0059] [Storage Department]

[0060] The storage portion 20 includes a frame portion 22 having a storage opening 21 formed in the center thereof. The storage opening 21 is configured to surround the outer periphery of the holding portion 10 and to be able to store the holding portion 10 therein.

[0061] Supporting parts 30A, 30B, and 30C are provided at a plurality of locations on the inner peripheral surface 23 which is the inner side of the storage opening 21. The storage portion 20 supports the holding portion 10 movably in the Z direction via the supporting parts 30A, 30B, and 30C.

[0062] In addition, driving parts 40A and 40B are provided at multiple locations on the inner peripheral surface 23. The driving parts 40A and 40B provided in the storage part 20 move the holding part 10 in the Z direction. The holding part 10 functions as a movable part driven by the driving parts 40A and 40B, and the storage part 20 functions as a fixed part relative to the holding part 10.

[0063] In a plan view, the inner peripheral surface 23 is formed to correspond to the shape of the outer peripheral surface 13 of the holding portion 10. Figure 3In the figure, the shapes of the outer peripheral surface 13 of the holding portion 10 and the inner peripheral surface 23 of the storage opening 21 are just examples and can be appropriately changed according to the arrangement of the support portions 30A, 30B, 30C and the drive portions 40A, 40B.

[0064] The frame 22 has a bottom 22a and a side wall 22b. The inner wall of the cover 3 is fixed to the bottom 22a by, for example, bonding. The substrate 50 is attached to the outer peripheral surface 24 of the side wall 22b.

[0065] [Supporting part]

[0066] The support parts 30A, 30B, and 30C support the holding part 10 so as to be movable in the Z direction relative to the storage part 20. Figure 3 As shown, the support portions 30A, 30B, and 30C are respectively arranged at three locations dispersed in the circumferential direction on the inner peripheral surface 23 (outer peripheral surface 13 ).

[0067] Although detailed illustrations are omitted, the supporting portions 30A, 30B, and 30C include: a first groove portion, which is provided on the outer peripheral surface 13 of the retaining portion 10; a second groove portion, which is provided on the inner peripheral surface 23 of the storage portion 20; and a rolling member (for example, a ball member, etc.) which is clamped between the first groove portion and the second groove portion and can roll.

[0068] In the support parts 30A, 30B, and 30C, the first groove part and the second groove part are arranged to extend in the Z direction and to face each other. The rolling member is rollably sandwiched between the first groove part and the second groove part arranged in this way.

[0069] One or more rolling members are arranged between the first groove and the second groove. When a plurality of rolling members are arranged between the first groove and the second groove, the tilt of the holding portion 10 can be suppressed more stably. In this case, the plurality of rolling members are arranged in a manner arranged along the Z direction, and are held by a holding member (not shown) in a manner that a fixed distance between them is maintained and positioning in the Z direction is possible.

[0070] The holding portion 10 is supported by the supporting portions 30A, 30B, and 30C configured in this manner so as to be movable in the Z direction relative to the housing portion 20 .

[0071] In addition, a track-shaped member made of a metal material or the like and capable of rolling the rolling member may be installed in the first groove portion and the second groove portion. The retaining portion 10 and the storage portion 20 are usually made of resin or the like, and the rolling member is usually made of ceramic, alloy or the like. Therefore, by providing a track-shaped member made of a metal material or the like that is harder than the retaining portion 10 and the storage portion 20 in the first groove portion and the second groove portion, the first groove portion and the second groove portion are difficult to deform even when subjected to a pressing force from the rolling member. With such a structure, the support portions 30A, 30B, 30C can stably support the retaining portion 10 while being movable in the Z direction.

[0072] [Drive unit]

[0073] The driving parts 40A and 40B drive the holding part 10 in the Z direction relative to the storage part 20. Figure 3 As shown, the drive units 40A and 40B are respectively arranged at two locations dispersed in the circumferential direction on the inner peripheral surface 23 (outer peripheral surface 13). The optical element driving device body 4 can drive the lens unit 2 together with the holding unit 10 in the Z direction through the above-mentioned support units 30A, 30B, 30C and the drive units 40A and 40B, thereby realizing the AF function.

[0074] like Figure 3 As shown, the frame portion 22 of the storage portion 20 has four corner portions 22bA, 22bB, 22bC, and 22bD. Figure 3 In the example shown, the support portion 30A is arranged at the corner portion 22bA, and therefore, the drive portions 40A and 40B are arranged at corner portions 22bB and 22bC which are different from the corner portion 22bA and are point-symmetrical with respect to the optical axis OA in a plan view. By arranging 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.

[0075] As the driving units 40A and 40B, ultrasonic motors which are actuators having piezoelectric elements are used.

[0076] Reference Figure 4A and Figure 4B The drive units 40A and 40B will be described. Figure 4A Yes Description Figure 3 FIG. 4 is a diagram of a driving unit 40A of the optical element driving device main body 4 shown. Figure 4B Viewed from the upper side in the Z direction Figure 4A FIG. 40A of the driving unit shown in FIG. Figure 4A and Figure 4B The driving unit 40A is shown in the figure, but the driving unit 40B has the same structure as the driving unit 40A, and its detailed illustration and description are omitted.

[0077] The driving unit 40A includes a piezoelectric element 41, a resonating unit 42, a power transmission unit 43 (a moving unit in the present invention), etc. The driving force generated by the resonating unit 42 by resonating with the vibration of the piezoelectric element 41 is transmitted to the power transmission unit 43. Although not shown in the figure, the power transmission unit 43 is fixed to the holding unit 10 side, and the driving force of the resonating unit 42 is transmitted to the holding unit 10 via the power transmission unit 43. In the driving unit 40A, the resonating unit 42 constitutes an active element, and the power transmission unit 43 constitutes a passive element.

[0078] The piezoelectric element 41 is a plate-shaped element formed of, for example, a ceramic material, and generates vibrations, for example, vibrations of a frequency in the ultrasonic region, by applying a high-frequency voltage. Two piezoelectric elements 41 are arranged so as to sandwich the body portion 42a (the main body in the present invention) of the resonance portion 42. Although not shown in the figure, the connection wiring provided in the FPC 51 described later is electrically connected to the piezoelectric element 41, and a voltage is applied to the piezoelectric element 41.

[0079] The resonance part 42 is formed of a plate member of a conductive material, and resonates with the vibration of the piezoelectric element 41 to convert the vibration motion into linear motion. The resonance part 42 is formed by laser processing, etching processing, or press processing of a metal plate, for example.

[0080] The resonance part 42 includes a body part 42a, a pair of arm parts 42b, a protrusion part 42c, a current-carrying part 42d, etc. The resonance part 42 further includes a contact member 44 to be described later.

[0081] The body portion 42a is a substantially rectangular portion that bonds the front and back surfaces of the two piezoelectric elements 41. Vibration generated by the piezoelectric element 41 is transmitted to the pair of arm portions 42b via the body portion 42a.

[0082] A pair of arm portions 42b extend along the Z direction from both side portions of the body portion 42a to the front end portions which become the free ends of each arm portion 42b. The pair of arm portions 42b have a symmetrical shape and deform symmetrically in resonance with the vibration of the piezoelectric element 41. The pair of arm portions 42b are formed so that their free ends clamp the power transmission portion 43. More specifically, the pair of arm portions 42b are configured so that their free ends abut against the abutment surface 43a of the power transmission portion 43 described later in the inward direction. In the present embodiment, as described later, the pair of arm portions 42b are configured to abut against the abutment surface 43a of the power transmission portion 43 via the abutment component 44. The pair of arm portions 42b respectively have a component storage portion (here, the ball storage portion 42e) which becomes a recessed portion for storing the abutment component 44.

[0083] The protrusion 42c extends from the center of the body 42a in the Z direction. A through hole through which a rivet or the like is inserted is formed in the protrusion 42c. The protrusion 42c is fixed to the storage portion 20 side using a rivet or the like.

[0084] The conducting portion 42d extends from the center of the body 42a to the side opposite to the protruding portion 42c. The conducting portion 42d is a portion that constitutes a power supply line to the piezoelectric element 41 via the body 42a, and is electrically connected to a connection wiring provided on the FPC 51, although not shown.

[0085] By the electrical connection, a voltage is applied to the piezoelectric element 41 attached to the body 42a in the thickness direction, and vibration is generated. The resonating part 42 has at least two resonant frequencies, and deforms in different behaviors with respect to each resonant frequency. In other words, the overall shape of the resonating part 42 is set to deform in different behaviors with respect to the two resonant frequencies.

[0086] Here, different behaviors refer to the behavior of the pair of arms 42b advancing and retreating the power transmission unit 43 in the Z direction. Therefore, by vibrating the resonance unit 42 at a desired resonance frequency, the pair of arms 42b can advance or retreat the power transmission unit 43 in the Z direction.

[0087] The power transmission part 43 is, for example, a rectangular parallelepiped having a predetermined length in the Z direction, and has a contact surface 43a for contact with the contact member 44 described later at a position opposite to the pair of arm parts 42b. As described above, the pair of arm parts 42b are configured to contact with the contact surface 43a, and the power transmission part 43 functions as a clamping guide relative to the pair of arm parts 42b. The power transmission part 43 is attached to the outer peripheral surface 13 of the frame part 12 of the holding part 10 at its end on the upper side (+Z side) in the figure.

[0088] At least the contact surface 43a of the power transmission part 43 or the entire power transmission part 43 is made of ceramic. As ceramic, for example, zirconium oxide, aluminum oxide, etc. can be used. When only the contact surface 43a is made of ceramic, for example, a plate made of ceramic can be arranged on the power transmission part 43 as the contact surface 43a (surface).

[0089] The contact member 44 is fixed to the ball receiving portion 42e of the front end portion (free end) of the pair of arm portions 42b, and contacts the contact surface 43a of the power transmission portion 43. The contact member 44 is made of ceramic. As ceramic, for example, zirconium oxide, aluminum oxide, etc. can be used. In addition, as an example, the contact member 44 is a spherical ball member.

[0090] Reference Figure 4A The conventional ultrasonic motor is described below. The tip of a pair of arms 42b is in contact with the contact surface 43a. As the piezoelectric element 41 vibrates, the tip of the arm 42b and the contact surface 43a come into frictional contact, and the power transmission unit 43 moves.

[0091] In this case, there is a problem that the driving sound generated by the front end of the arm portion 42b and the contact surface 43a in frictional contact is louder than that of a voice coil motor, etc. This is because one or both of the parts in frictional contact are ground, and this grinding becomes the main cause, and the driving sound becomes louder. For example, when the parts in frictional contact are made of stainless steel, one or both of the stainless steel is ground, and the driving sound becomes louder.

[0092] Therefore, in this embodiment, at least the contact surface 43a or the entire power transmission part 43 is formed of, for example, ceramics. In addition, in the pair of arm parts 42b, contact members 44 are arranged at their front ends, and the contact members 44 are formed of, for example, ceramics.

[0093] Thus, the abutting member 44 and the abutting surface 43a, which are the mutually abutting parts in the resonance part 42 and the power transmission part 43, are both made of ceramics. Thus, the hardness of the abutting member 44 and the abutting surface 43a is respectively increased and equal to each other, so that the wear between the parts can be suppressed, and as a result, the driving sound can be reduced.

[0094] The present inventors have confirmed that the driving noise is reduced by at least 5 to 10 dB compared to a conventional structure where the frictionally contacting members, for example, are made of stainless steel, by making the contacting member 44 and the contacting surface 43a, which are the frictionally contacting members, out of ceramics.

[0095] In addition, in the conventional structure, the abutting forces between the front ends of the pair of arm portions 42b and the corresponding abutting surfaces 43a are different or the abutting directions are asymmetric, depending on the processing accuracy of the resonance portion 42 and the power transmission portion 43, the position accuracy during assembly, etc. That is, there is a deviation in the abutting state between the front ends of the pair of arm portions 42b and the corresponding abutting surfaces 43a.

[0096] In contrast, in the present embodiment, the contact member 44 is a spherical ball member. Thus, the contact forces between the front ends of the pair of arm portions 42b, i.e., the contact member 44 and the corresponding contact surface 43a, are equal or substantially equal, and the contact directions are symmetrical or substantially symmetrical, which can suppress the deviation of the contact state. In this way, the deviation of the contact state can be suppressed, and thus, the assembly of the resonance portion 42, the power transmission portion 43, etc. becomes easy.

[0097] According to the structure described above, when a voltage is applied to the piezoelectric element 41 of the driving unit 40A, the piezoelectric element 41 vibrates, the resonance unit 42 deforms in a behavior corresponding to the frequency, and the pair of arm portions 42b also deforms in a behavior corresponding to the frequency. The pair of arm portions 42b abuts against the power transmission unit 43 inwardly by pressing it, and the driving force generated by the deformation of the pair of arm portions 42b is transmitted to the power transmission unit 43, and the power transmission unit 43 moves relative to the resonance unit 42 in the Z direction. In this way, the driving force of the driving unit 40A is transmitted to the holding unit 10, thereby the holding unit 10 moves in the Z direction to perform focusing.

[0098] Furthermore, in the present embodiment, as described above, in the resonance portion 42 and the power transmission portion 43 , the abutting member 44 and the abutting surface 43 a , which are portions abutting against each other, are formed of ceramics having high hardness, thereby making it possible to reduce the driving noise.

[0099] [Substrate part]

[0100] The substrate unit 50 has a circuit for driving the driving units 40A and 40B. The substrate unit 50 has a FPC (Flexible Printed Circuit) 51, a driver IC 52, position detection sensors 54A and 54B, and the like.

[0101] The FPC 51 is a flexible substrate, and is composed of a thin insulating layer such as a resin film and a metal layer such as copper foil. Although not shown in the figure, the metal layer forms a circuit of a signal line and a power line, and is electrically connected to the drive units 40A, 40B, the driver IC 52, the position detection sensors 54A, 54B, etc.

[0102] The driver IC 52 is an IC that controls a drive signal for driving the drive units 40A and 40B. The driver IC 52 outputs a drive signal based on a detection signal detected by the position detection sensors 54A and 54B, for example, and outputs the output drive signal to the drive units 40A and 40B.

[0103] The position detection sensors 54A and 54B are, for example, magnetic sensors such as Hall elements. The position detection sensors 54A and 54B detect the strength of the magnetic force of the magnets 14A and 14B arranged opposite to each other, obtain the relative position of the holding portion 10 and the storage portion 20 in the Z direction, and output it as a detection signal. Here, two position detection sensors 54A and 54B are provided, but the position detection sensor may be one, and in this case, the magnet arranged opposite to each other may be one.

[0104] Although not shown in the figure, connection wiring electrically connected to the drive units 40A and 40B is provided on the FPC 51 .

[0105] In addition, the FPC 51 may include an inductor that boosts the voltage (input voltage) of the drive signal input from the driver IC 52 and outputs the boosted voltage to the drive units 40A and 40B, respectively.

[0106] The FPC 51 is a single long substrate for mounting the driver IC 52 and the position detection sensors 54A and 54B described above on the FPC 51 . The FPC 51 is disposed along the outer peripheral surface 24 of the frame 22 of the storage portion 20 so as to substantially surround the outer peripheral surface 24 .

[0107] In order to arrange the FPC 51 along the outer peripheral surface 24, for example, the outer peripheral surface 24 of the corner 22bA is formed into an arc shape in a plan view. Thus, the FPC 51 can be arranged in close contact with the outer peripheral surface 24 of the corner 22bA. Therefore, it is not necessary to increase the size of the cover 3 arranged outside the FPC 51, and the overall miniaturization of the device can be achieved, which can achieve cost reduction.

[0108] [Other embodiments]

[0109] The present invention is not limited to the above-described embodiments, and can be modified within a scope not departing from the gist of the invention.

[0110] For example, in the above embodiment, the smartphone M is used as an example for explanation, but the present invention can be applied to a camera-mounted device having a camera module and an image processing unit that processes image information obtained by the camera module. The camera-mounted device includes information equipment and transportation equipment. Information equipment includes, for example, mobile phones with cameras, laptop computers, tablet terminals, portable game consoles, web cameras, and vehicle-mounted devices with cameras (for example, rear monitor devices, driving recorder devices). In addition, transportation equipment includes, for example, cars and drones.

[0111] Figure 5A , Figure 5B 1 is a diagram showing a vehicle V as a camera-mounted device equipped with a vehicle-mounted camera module VC (Vehicle Camera). Figure 5A This is the front view of the car V. Figure 5B FIG. 1 is a rear perspective view of a car V. The car V is equipped with the camera module A described in the above embodiment as a vehicle-mounted camera module VC. Figure 5A , Figure 5B As shown, the vehicle-mounted camera module VC is mounted on the front windshield, for example, facing forward, or mounted on the rear door, facing backward. The vehicle-mounted camera module VC is used for rear monitoring, driving recorder, collision avoidance control, automatic driving control, and the like.

[0112] In the above embodiment, the optical element driving device 1 that drives the lens unit 2 as an optical element is described, but the optical element to be driven may be an optical element other than a lens such as a reflector or a prism, or may be an optical element such as the imaging element 502. In this case, the opening 11 of the holding portion 10 may be changed in shape according to the shape of the optical element to be mounted, or may be eliminated according to circumstances.

[0113] Furthermore, in the above-described embodiment, the optical element driving device 1 has the AF function, but may have not only the AF function but also a function of moving the lens unit 2 in the Z direction, such as a zoom function.

[0114] In addition, in the above embodiment, the optical element driving device 1 having the AF function is described as an example, but the optical element driving device 1 may also have the OIS function. In the case of having the OIS function, the optical element driving device 1 includes: a base that supports the storage portion 20 via the OIS support portion so that it can move in the X direction and the Y direction; and an OIS driving portion that drives the storage portion 20 in the X direction and the Y direction relative to the base. In this case, as the OIS driving portion, for example, it is sufficient to be configured to drive the storage portion 20 in the X direction and the Y direction using the above-mentioned driving portion 40A.

[0115] In the above embodiment, the contact member 44 is a spherical ball member, but is not limited to this shape and may be other shapes. For example, the contact member 44 may be cylindrical or semi-cylindrical and the curved surface may be the part that contacts the contact surface 43a.

[0116] In the above embodiment, the ball receiving portion 42e and the contact member 44 are provided at the front end of the arm portion 42b, but the front end of the arm portion 42b may be coated with ceramic instead of providing the ball receiving portion 42e and the contact member 44. The contact surface 43a of the power transmission portion 43 is also the same, and the surface of the contact surface 43a may be coated with ceramic.

[0117] In addition, in the above-mentioned embodiment, the free ends of the pair of arm portions 42b of the resonance portion 42 clamp the power transmission portion 43, but as long as the resonance portion 42 and the power transmission portion 43 are in contact with each other, it is not limited to such a structure, and other structures may be used. For example, it may be configured so that the corresponding power transmission portions 43 are respectively arranged on the outside of the pair of arm portions 42b, and the free ends of the pair of arm portions 42b are in contact with each other toward the outside direction. In addition, it may be configured so that the resonance portion 42 has one arm portion 42b, and the free end of one arm portion 42b is in contact with the power transmission portion 43.

[0118] In the above embodiment, the resonance unit 42 is fixed to the storage unit 20 side and the power transmission unit 43 is fixed to the holding unit 10 side. However, the resonance unit 42 may be fixed to the holding unit 10 side and the power transmission unit 43 may be fixed to the storage unit 20 side.

[0119] The above is an explanation of the embodiments of the present invention. In addition, the above explanation is an illustration of the preferred embodiments of the present invention, and the scope of the present invention is not limited thereto. That is, the explanation of the structure of the above-mentioned device and the shape of each part is an example, and it is obvious that various changes and additions can be made to these examples within the scope of the present invention.

[0120] Industrial Applicability

[0121] The optical element driving device and camera module of the present invention are useful when mounted on camera-mounted devices such as smartphones, mobile phones, digital cameras, notebook computers, tablet terminals, portable game consoles, car cameras, and drones.

[0122] Explanation of symbols

[0123] 1 optical element driving device;

[0124] 2. Lens unit;

[0125] 3 hoods;

[0126] 4 optical element driving device body;

[0127] 5. Filming Department;

[0128] 10. holding part;

[0129] 11 opening;

[0130] 12 frame;

[0131] 13 outer peripheral surface;

[0132] 14A, 14B magnets;

[0133] 20 storage department;

[0134] 21 storage opening;

[0135] 22 frame portion;

[0136] 23 inner circumference;

[0137] 24 outer peripheral surface;

[0138] 30A, 30B, 30C support parts;

[0139] 40A, 40B driving unit;

[0140] 41 piezoelectric element;

[0141] 42 resonance part;

[0142] 42a body;

[0143] 42b arm;

[0144] 42c protrusion;

[0145] 42d power supply unit;

[0146] 42e ball storage unit;

[0147] 43 power transmission unit;

[0148] 43a abutment surface;

[0149] 44 abutment member;

[0150] 50Substrate Department;

[0151] 51FPC;

[0152] 52 driver IC;

[0153] 54A, 54B position detection sensors;

[0154] 301 opening;

[0155] 501 image sensor substrate;

[0156] 502 shooting element;

[0157] 503 Control Unit.

Claims

1. A driving device, characterized in that: have: a resonating portion having a pair of arm portions and resonating with the vibration of the piezoelectric element; and a moving portion that contacts the pair of arm portions and moves relative to the resonating portion as the resonating portion vibrates, In the resonating part and the moving part, the mutually contacting parts are respectively made of ceramics. The pair of arm portions have spheres made of ceramic as portions that come into contact with the moving portion.

2. The driving device according to claim 1, characterized in that: The entire moving part is made of ceramic.

3. The driving device according to claim 1, characterized in that: A surface of the moving portion that contacts the resonating portion is made of ceramic.

4. The driving device according to claim 1, characterized in that: The pair of arm portions includes a ball receiving portion for receiving the ball.

5. An optical element driving device, characterized in that: have: a holding portion capable of holding the optical element; a housing portion for housing the holding portion so as to be movable in the optical path direction of the optical element; and The driving device according to any one of claims 1 to 4, which drives the holding portion.

6. A camera module, characterized in that: have: The optical element driving device according to claim 5; and The imaging unit uses the optical element to capture an image of a subject.

7. A camera-mounted device, which is an information device or a transportation device, characterized in that: The camera-mounted device has: The camera module of claim 6; and An image processing unit processes the image information obtained by the camera module.

Images