JP2012005957A - Driving device, image acquiring device, and electronic equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily obtain intended operating characteristics of a driving device even when a driving circuit including an additional circuit element is configured.SOLUTION: The driving device displaces a lens holder 31 relative to a housing 20 by the drive of a piezoelectric element 50. The housing 20 is mounted with the lens holder 31 in a state where the lens holder 31 can be displaced according to the drive of the piezoelectric element 50, and is provided with a pair of lead terminals 81, 82 for connecting a pair of electrode terminals 50a, 50b of the piezoelectric element 50 individually to the outside. At least one of a pair of wirings formed between a pair of the electrode terminals 50a, 50b and a pair of the lead terminals 81, 82 includes a circuit element (coil chip 95) included in a circuit for supplying a drive voltage waveform to the piezoelectric element 50.

Description

  The present invention relates to a drive device, an image acquisition device, and an electronic apparatus. In particular, the present invention relates to a driving device that displaces a moving object based on driving of a piezoelectric element.

  In recent years, cameras have been incorporated into a wide variety of products. When a camera is mounted on a small electronic device such as a mobile phone or a notebook computer, it is strongly required to reduce the size of the camera itself.

  An autofocus lens may be incorporated in the camera. In this case, downsizing of the actuator that displaces the lens is strongly desired. As a small actuator, one that moves a moving object by driving a piezoelectric element is known.

  Patent Document 1 discloses a driving device in which a piezoelectric element and a drive shaft move in synchronization with a moving object in a state where the piezoelectric element is separated from a fixed member. This makes it possible to easily set the frequency of the drive waveform applied to the piezoelectric element without considering the resonance of the fixed member.

  Patent Document 2 discloses a piezoelectric actuator capable of applying a high voltage so as to reduce inrush current, keep power consumption low, and easily escape from a fixed state. In the drive circuit disclosed in Patent Document 2, inductive elements are connected in series to the piezoelectric elements.

  Patent Document 3 discloses a driving device that reduces the inrush current when driving by applying a voltage to a capacitive load. This driving device includes a discharge circuit in which inductive elements are connected to both ends of a load capacity capacitor.

Japanese Patent No. 4372206 JP 2005-237144 A JP 2003-153560 A

  When a camera module purchaser incorporates a drive circuit for a piezo element, it may not be easy to adjust the operating characteristics of the camera module presented by the camera module supplier. The operating characteristics of the camera module naturally depend on the operating characteristics of the drive circuit that drives the piezo element arranged in the camera module housing, and the operating characteristics of the drive circuit itself that drives the piezo element and the operation of the camera module itself. This is because characteristics cannot be considered separately.

  For example, when an additional circuit element such as an inductor is connected in the drive circuit, it is not easy for the purchaser to realize the operating characteristics of the camera module presented by the supplier of the camera module by the inductor to be selected. In some cases. Since there are many types of inductors, it is often not known through trial and error operation verification which inductor can be used to ensure the intended operating characteristics of the camera module.

  As is apparent from the above description, it is strongly desired to easily realize the intended operation characteristics of the drive device even when the drive circuit is configured including additional circuit elements.

  The drive device according to the present invention is a drive device that displaces a moving object with respect to a fixed-side member based on driving of a piezoelectric element, and the fixed-side member moves the movement according to driving of the piezoelectric element. The moving object is attached in a state where the object is displaceable, and a set of lead terminals for individually connecting a set of electrode terminals of the piezoelectric element to the outside are provided, and the set of the electrodes At least one of the set of wirings formed between the terminal and the set of lead terminals includes a circuit element included in a circuit that supplies a drive voltage waveform to the piezoelectric element. By adopting this configuration, it is possible to easily realize the intended operating characteristics of the driving device even when the driving circuit is configured including additional circuit elements.

  The circuit element may be a coil formed of a chip shape or a wiring pattern.

  It is preferable to further include a mounting substrate including the coil.

  The fixed-side member includes an envelope that surrounds the object to be moved, the envelope includes a set of the lead terminals, and the mounting board is disposed inside the envelope. Good.

  The mounting board includes a set of connection terminals connected to the set of the lead terminals, and when the mounting board is disposed in the envelope, the set of the lead terminals and the set of the connections. The terminals are preferably arranged to face each other.

  The envelope is a polygonal box-shaped member having a plurality of side walls, and the mounting substrate includes a first substrate portion extending along a first side wall of the envelope, and the envelope A second board part extending along the second side wall may be provided, and the wiring pattern may be formed on the first board part and the second board part.

  A drive voltage generation circuit as the circuit for supplying a drive voltage waveform to the piezoelectric element may be further provided.

  The drive voltage generation circuit includes: a first drive circuit that applies a drive voltage from one side electrode of the piezoelectric element; and a second drive circuit that applies a drive voltage from the other side of the piezoelectric element. An alternating drive voltage for expanding and contracting the piezoelectric element is generated by switching between a drive circuit and the second drive circuit, and the first drive circuit and the second drive circuit are respectively used as the circuit elements. With inductive elements,

  The frequency of the drive voltage waveform is a frequency range in which the gain is greater than zero dB due to the interaction of the switch resistance, the capacitance of the piezoelectric element, and the inductance of the inductive element included in the first and second drive circuits. It is good to be selected from.

  The frequency of the drive voltage waveform is from a frequency range in which the gain is greater than 2 dB due to the interaction of the switch resistance, the capacitance of the piezoelectric element, and the inductance of the inductive element included in the first and second drive circuits. It is good to be selected.

  The frequency of the drive voltage waveform is a frequency range in which the gain is greater than zero by the interaction of the switch resistance included in the first and second drive circuits, the capacitance of the piezoelectric element, and the inductance of the inductive element. In addition, 10% before and after the frequency of the resonance point may be selected from the excluded frequency range.

  The frequency of the drive voltage waveform is a frequency range in which the gain is greater than zero by the interaction of the switch resistance included in the first and second drive circuits, the capacitance of the piezoelectric element, and the inductance of the inductive element. It is preferable that the frequency range is smaller than the frequency of the resonance point.

  A driving device according to the present invention includes a piezoelectric element having a pair of electrode terminals, a driving shaft that receives vibration transmitted from the piezoelectric element in accordance with the driving of the piezoelectric element, and a displacement that is displaced in accordance with the driving of the piezoelectric element. A set of lead terminals, to which the moving object is attached in a state in which the moving object is displaceable in accordance with the driving of the piezoelectric element and the set of electrode terminals individually connected to the outside; A fixed-side member, and one of a set of wires included in a circuit that supplies a driving voltage waveform to the piezoelectric element and formed between the set of electrode terminals and the set of lead terminals A first circuit element included.

  Second included in the circuit for supplying a driving voltage waveform to the piezoelectric element and included in the other of the set of wirings formed between the set of electrode terminals and the set of lead terminals. It is preferable to further include a circuit element.

  The first and second circuit elements may be coils formed in a chip shape or a wiring pattern.

  It is preferable to further include a mounting substrate including the coil.

  The fixed-side member includes an envelope that surrounds the object to be moved, the envelope includes a set of the lead terminals, and the mounting board is disposed inside the envelope. Good. The moving object may include a lens holder including a lens.

  An image acquisition apparatus according to the present invention includes the above-described driving device and an imaging element that captures an image input via the lens. An electronic apparatus according to the present invention includes the above-described image acquisition device.

  According to the present invention, even if a drive circuit is configured including additional circuit elements, the intended operation characteristics of the drive device can be easily realized.

1 is a schematic exploded perspective view of a camera module according to a first embodiment of the present invention. It is a schematic perspective view of the component concerning 1st Embodiment of this invention. 1 is a schematic perspective view of a camera module according to a first embodiment of the present invention. 1 is a schematic perspective view of a lens unit according to a first embodiment of the present invention. It is a schematic diagram which shows schematic cross-sectional structure of the lens unit concerning 1st Embodiment of this invention. It is a schematic fragmentary perspective view of the camera module before arrangement | positioning of the coil mounting board | substrate concerning 1st Embodiment of this invention. It is a schematic fragmentary perspective view of the camera module after arrangement | positioning of the coil mounting board | substrate concerning 1st Embodiment of this invention. 1 is a schematic partial top view of a camera module according to a first embodiment of the present invention. 1 is a schematic partial top view of a camera module according to a first embodiment of the present invention. It is a schematic diagram which shows schematic cross-sectional structure of the camera module concerning 1st Embodiment of this invention. It is a schematic schematic diagram which shows the attachment method of the terminal board concerning 1st Embodiment of this invention. It is a schematic schematic diagram which shows the attachment method of the terminal board concerning 1st Embodiment of this invention. It is a schematic perspective view of the housing | casing concerning 1st Embodiment of this invention. 1 is a schematic cross-sectional schematic diagram of a camera module according to a first embodiment of the present invention. It is explanatory drawing which shows the wiring relationship in the housing | casing concerning 1st Embodiment of this invention. 1 is a circuit diagram of a drive circuit according to a first embodiment of the present invention. 3 is a timing chart for explaining the operation of the drive circuit according to the first embodiment of the present invention. 1 is a circuit diagram of a drive circuit according to a first embodiment of the present invention. 1 is a circuit diagram of a drive circuit according to a first embodiment of the present invention. It is explanatory drawing which shows the relationship between the drive voltage waveform concerning 1st Embodiment of this invention, and the displacement of a lens holder. It is explanatory drawing which shows the relationship between the expansion-contraction of the piezoelectric element concerning 1st Embodiment of this invention, and the displacement of a lens holder. FIG. 3 is an equivalent circuit diagram of each of the first and second drive circuits according to the first embodiment of the present invention. It is a figure which shows the simulation result of the circuit operation | movement of the drive circuit concerning 1st Embodiment of this invention. It is the figure which extracted the area | region in the middle of a gain rising toward the resonance point peak in FIG. It is a figure which shows the simulation result of the circuit operation | movement of the drive circuit concerning 1st Embodiment of this invention. It is a figure which shows the simulation result of the circuit operation | movement of the drive circuit concerning 1st Embodiment of this invention. It is a figure for demonstrating that the harmonic component of a drive signal can be suppressed. It is a figure which shows the example of the drive voltage on which the power line noise carried. It is a figure which shows the example of the drive voltage which suppressed the power supply line noise by the filter effect. It is a circuit diagram concerning the 1st modification of a drive circuit of a 1st embodiment of the present invention. It is a circuit diagram concerning the 2nd modification of a drive circuit of a 1st embodiment of the present invention. It is explanatory drawing for demonstrating operation | movement of the circuit which concerns on a 2nd modification. It is explanatory drawing for demonstrating operation | movement of the circuit which concerns on a 2nd modification. 1 is a schematic diagram of a mobile phone according to a first embodiment of the present invention. It is a block diagram which shows the system configuration | structure concerning 1st Embodiment of this invention. It is a schematic exploded perspective view of the camera module concerning a 2nd embodiment of the present invention. It is a schematic fragmentary perspective view of the camera module before arrangement | positioning of the coil mounting board | substrate concerning 2nd Embodiment of this invention. It is a schematic fragmentary perspective view of the camera module after arrangement | positioning of the coil mounting board | substrate concerning 2nd Embodiment of this invention. It is a schematic perspective view of the coil mounting substrate concerning 2nd Embodiment of this invention. It is a schematic diagram which shows the wiring pattern formed on the coil mounting board | substrate concerning 2nd Embodiment of this invention. It is a coil mounting board | substrate which concerns on the modification of 2nd Embodiment of this invention. It is a schematic exploded perspective view of the camera module concerning a 3rd embodiment of the present invention. It is a schematic fragmentary perspective view of the camera module before arrangement | positioning of the coil mounting board | substrate concerning 3rd Embodiment of this invention. It is a schematic fragmentary perspective view of the camera module after arrangement | positioning of the coil mounting board | substrate concerning 3rd Embodiment of this invention. It is a schematic perspective view of the coil mounting board | substrate concerning 3rd Embodiment of this invention. It is a coil mounting board | substrate which concerns on the modification of 3rd Embodiment of this invention. It is a schematic diagram which shows schematic structure of the camera module which concerns on 4th Embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Each embodiment is simplified for convenience of explanation. Since the drawings are simple, the technical scope of the present invention should not be interpreted narrowly based on the drawings. The drawings are only for explaining the technical matters, and do not reflect the exact sizes or the like of the elements shown in the drawings. The same elements are denoted by the same reference numerals, and redundant description is omitted. Words indicating directions such as up, down, left, and right are used on the assumption that the drawing is viewed from the front. The embodiments are not completely independent of each other and can be combined. Moreover, the effect based on the combination of each embodiment shall also be assertable.

[First Embodiment]
Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a schematic exploded perspective view of a camera module. FIG. 2 is a schematic perspective view of the wiring board and the like. FIG. 3 is a schematic perspective view of the camera module. FIG. 4 is a schematic perspective view of the lens unit. FIG. 5 is a schematic diagram illustrating a schematic cross-sectional configuration of the lens unit. FIG. 6 is a schematic partial perspective view of the camera module before arrangement of the coil mounting board. FIG. 7 is a schematic partial perspective view of the camera module after arrangement of the coil mounting board. FIG. 8 is a schematic partial top view of the camera module. FIG. 9 is a schematic partial top view of the camera module. FIG. 10 is a schematic cross-sectional schematic diagram of the camera module. 11 and 12 are schematic schematic diagrams showing a method of attaching the terminal board. FIG. 13 is a schematic perspective view of the housing. FIG. 14 is a schematic sectional view of the camera module. FIG. 15 is an explanatory diagram showing the wiring relationship in the housing. FIG. 16 is a circuit diagram of the drive circuit. FIG. 17 is a timing chart for explaining the operation of the drive circuit. 18 and 19 are circuit diagrams of the drive circuit. FIG. 20 is an explanatory diagram showing the relationship between the drive voltage waveform and the displacement of the lens holder. FIG. 21 is an explanatory diagram showing the relationship between expansion and contraction of the piezoelectric element and displacement of the lens holder. FIG. 22 is an equivalent circuit diagram of each of the first and second drive circuits included in the drive circuit. FIG. 23 is a diagram illustrating a simulation result of the circuit operation of the drive circuit. FIG. 24 is a diagram in which a region in the middle of the gain increasing toward the resonance point peak in FIG. 23 is extracted. FIG. 25 is a diagram illustrating a simulation result of the circuit operation of the drive circuit. FIG. 26 is a diagram illustrating a simulation result of the circuit operation of the drive circuit. FIG. 27 is a diagram for explaining that the harmonic component of the drive signal can be suppressed. FIG. 28 is a diagram illustrating an example of a drive voltage in which power supply line noise is added. FIG. 29 is a diagram illustrating an example of a drive voltage in which power supply line noise is suppressed by the filter effect. FIG. 30 is a circuit diagram according to a first modification of the drive circuit. FIG. 31 is a circuit diagram according to a second modification of the drive circuit. FIG. 32 is an explanatory diagram for explaining the operation of the circuit according to the second modification. FIG. 33 is an explanatory diagram for explaining the operation of the circuit according to the second modification. FIG. 34 is a schematic diagram of a mobile phone. FIG. 35 is a block diagram showing a system configuration.

  As shown in FIGS. 1 to 4, a camera module (image acquisition device) 100 includes a wiring board 10, an image sensor (imaging device) 12, a transparent substrate 13, a housing (envelope) 20, and a lens unit (lens component). ) 30, a lid 60, and a coil mounting board 90. The casing 20 is provided with lead terminals (connection terminals, terminal plates, terminal portions, electrode terminals) 81 and 82. The image sensor 12 has an imaging region (pixel arrangement region) 12a. Pixels are arranged in a matrix in the imaging region 12a.

  The camera module 100 picks up an image with the image sensor 12 receiving a light beam coming from the object side through a lens held by the lens unit 30. The camera module 100 has an autofocus function, and the camera module 100 includes a lens driving device.

  As shown in FIG. 1, an image sensor 12, a transparent substrate 13, a housing 20, a coil mounting substrate 90, a lens unit 30, and a lid 60 are disposed on the wiring substrate 10. The housing 20 functions as a fixed-side member that does not move when viewed from the lens unit 30 that is a moving object. Similarly, the coil mounting substrate 90, the lid 60, the image sensor 12, the transparent substrate 13, and the wiring substrate 10 also function as fixed-side members.

  A housing 20 is disposed at one end of the wiring board 10, and a connector 10p is disposed at the other end of the wiring board 10 (see FIG. 2). The wiring board 10 is a flexible sheet-like wiring board (flexible wiring board). The wiring board 10 functions as a transmission path for a control signal input to the image sensor 12 and a video signal output from the image sensor 12. The wiring board 10 functions as a transmission path for driving voltage input to the piezo element 50.

  On the upper surface of the wiring substrate 10, recesses 11 a and 11 b are provided corresponding to the lead terminals 81 and 82. When the housing 20 is mounted on the wiring board 10, the lead terminal 81 is placed in the recess 11a, and the lead terminal 82 is placed in the recess 11b. For example, by providing wiring in the recesses 11 a and 11 b, electrical connection between the lead terminals 81 and 82 and the wiring in the wiring board 10 can be ensured according to the mounting of the housing 20 on the wiring board 10. Can do. Thereafter, the lead terminals 81 and 82 and the wiring board 10 may be electrically connected by soldering or the like.

  The transparent substrate 13 is a plate-like member that is substantially transparent to input light. The top view shape of the transparent substrate 13 is a square. The image sensor 12 is bump-connected to the back surface of the transparent substrate 13. The image sensor 12 and the wiring substrate 10 are electrically connected via a wiring pattern formed on the back surface of the transparent substrate 13. Specifically, on the back surface of the transparent substrate 13, a first pad group that is bump-connected to the pad group of the image sensor 12, a second pad group that is bump-connected to the pad group of the wiring substrate 10, and It is assumed that a wiring group that connects each pad included in the first pad group and each pad included in the second pad group is formed. In this case, the pad group of the image sensor 12 is connected to the first pad group provided on the back surface of the transparent substrate 13 via a plurality of bumps. The pad group provided with the wiring substrate 10 is connected to the second pad group provided on the back surface of the transparent substrate 13 through a plurality of bumps.

  The image sensor 12 is a general solid-state image sensor such as a CCD (Charge Coupled Device) sensor or a CMOS (Complementary Metal Oxide Semiconductor) sensor. The imaging region 12a of the image sensor 12 has a plurality of pixels arranged in a matrix on the XZ plane. Each pixel accumulates electric charge according to the amount of input light by photoelectric conversion. The electric charge accumulated in each pixel is read from each pixel by transfer control and supplied to the subsequent circuit. As shown in FIG. 2, the size of the image sensor 12 is sufficiently smaller than the transparent substrate 13 and is suitable for bonding the image sensor 12 to the transparent substrate 13.

  The housing 20 is mounted on the wiring board 10. A plurality of convex portions are provided on the lower end surface of the housing 20. Correspondingly, the wiring board 10 is provided with a plurality of recesses. The housing 20 is suitably positioned and fixed on the wiring board 10 by fitting between the convex portion and the concave portion.

  The housing 20 stores the image sensor 12 and the transparent substrate 13 in the lower space (lower storage chamber), and stores the coil mounting substrate 90 and the lens unit 30 in the upper space (upper storage chamber). By adopting the housing 20, the camera function can be modularized. The lower end surface of the housing 20 is fixed to the wiring substrate 10 with a black adhesive. Thereby, it is possible to suppress the entry of extraneous light into the housing 20. The housing 20 is manufactured by molding a black resin, for example. A black resin having good heat resistance and slidability is preferable, and a composite material of potassium titanate fiber and resin is preferable.

  The lid 60 is a flat plate-like member having an opening at a position corresponding to the optical axis of the lens. For example, the lid 60 is manufactured by molding a black resin. The lens unit 30 is confined in the housing 20 by attaching the lid 60 to the housing 20. The lid 60 is preferably attached to the housing 20 by screws. The lid 60 can be attached to and detached from the housing 20 by fixing the lid 60 to the housing 20 with screws instead of adhesively fixing. This makes it possible to remove the cause of the failure of the camera module 100 determined to be defective in the operation test after the test. For example, the yield of the camera module can be improved by removing dust that has entered the imaging area of the image sensor 12 after the operation test. The lid 60 is manufactured by molding a resin, for example. The lid 60 may be bonded and fixed to the housing 20.

  As shown in FIG. 4, the lens unit 30 includes a lens holder (lens holder) 31, a piezoelectric element (piezoelectric element, vibration element, vibration source) 50, a transmission shaft (drive shaft, shaft body) 51, and a shaft holder. 40.

  The lens holder 31 is a cylindrical member and holds the lenses OL1 to OL3 (see FIG. 14). An opening OP <b> 1 is provided in the upper plate portion of the lens holder 31. The upper plate portion of the lens holder 31 functions as an optical stop. On the outer periphery of the lens holder 31, a connecting portion 32 to which the transmission shaft 51 is connected is provided. The connection part 32 is comprised from support plate 32a, 32b. The support plates 32a and 32b fixedly support the transmission shaft 51. Note that the lens unit 30 may be grasped without including the shaft holding unit 40. The lens holder 31 is manufactured by molding black resin, for example. A black resin having good heat resistance and slidability is preferable, and a composite material of potassium titanate fiber and resin is preferable.

  The lens unit 30 is movable along the y-axis (axis parallel to the optical axes of the lenses OL1 to OL3) in accordance with the driving of the piezo element 50. However, the shaft holding unit 40 is fixed to the housing 20 and does not move in accordance with the driving of the piezo element 50. By adjusting the arrangement height of the lenses OL <b> 1 to OL <b> 3 with respect to the imaging region 12 a of the image sensor 12, a subject image can be formed on the imaging region of the image sensor 12 as intended.

  The piezo element 50 and the transmission shaft 51 are fixed to each other by an adhesive 70 (see FIG. 14). The transmission shaft 51 is connected to the lens holder 31 via the connecting portion 32. Specifically, the transmission shaft 51 is press-fitted into the openings of the support plates 32 a and 32 b of the connecting portion 32.

  In the case of adopting another driving method in which the piezo element 50 is fixed directly or indirectly to the housing 20 instead of the lens holder 31, the mounting surface of the housing 20 on which the piezo element 50 is placed is used. On the other hand, the piezo element 50 may be disposed at an inclination. The same applies to the case where the transmission shaft 51 is fixed to the housing 20. In the present embodiment, the transmission shaft 51 is fixed to the lens holder 31, and the piezo element 50 is fixed to the lens holder 31 via the transmission shaft 51. Therefore, the placement error of the piezo element 50 and the transmission shaft 51 with respect to the housing 20 does not become a problem.

  The relative positional relationship between the lens holder 31, the piezo element 50, and the transmission shaft 51 is fixed. Moreover, these are movable relatively with respect to the axis | shaft holding | maintenance part 40 (casing 20) which functions as a stationary member.

  The piezo element 50 is a general piezoelectric element in which ceramic layers (piezoelectric layers) are laminated. The piezo element 50 has a pair of electrode terminals 50a and 50b. A lead wire (conductive wire) 50 is connected to each electrode terminal 50a, 50b. Specifically, the lead wire 52a is connected to the electrode terminal 50a. A lead wire 52b is connected to the electrode terminal 50b. By continuously supplying a sawtooth voltage waveform between the pair of electrode terminals 50a and 50b, the piezoelectric element 50 continuously expands and contracts in the Y-axis direction.

  The transmission shaft 51 is a rod-like body whose longitudinal direction is the y-axis direction. The transmission shaft 51 is fixed to the upper surface of the piezo element 50 by an adhesive 70. Note that the transmission shaft 51 may be fixed to the piezo element 50 by a method other than an adhesive. The method of connecting the piezo element 50 and the transmission shaft 51 is arbitrary, and the transmission shaft 51 and the piezo element 50 may be connected to each other by fitting.

  The transmission shaft 51 transmits the vibration generated in the piezo element 50 to the shaft holding unit 40. The shaft holding part 40 holds the transmission shaft 51 in a slidable state and is fixed to the housing 20. Accordingly, the vibration generated in the piezo element 50 causes the piezo element 50, the transmission shaft 51, and the lens holder 31 to be displaced with respect to the housing 20 and the shaft holding unit 40.

  The transmission shaft 51 is desirably lightweight and highly rigid. The transmission shaft 51 is made of a material having a specific gravity of 2.1 or less. More preferably, the transmission shaft 51 is made of a material having a specific gravity of 2.1 or less and an elastic modulus of 20 GPa or more. More preferably, the transmission shaft 51 is made of a material having a specific gravity of 2.1 or less and an elastic modulus of 30 GPa or more. Thereby, the resonance frequency can be shifted to the high frequency side, and a continuous usable frequency band can be obtained.

  The transmission shaft 51 is preferably molded from glassy carbon, fiber reinforced resin, or epoxy resin. Particularly preferred are glassy carbon composites containing graphite, fiber reinforced resins and glass containing carbon, and epoxy resin composites containing carbon.

  A rail receiving portion (rotation inhibiting portion) 35 is provided on the outer peripheral surface of the lens holder 31. The rail receiving portion 35 receives the rail 25 (see FIG. 8) provided in the housing 20. The rail receiving part 35 is composed of a pair of protrusions 35a and 35b. A predetermined interval is provided between the rail receiving portion 35 and the rail 25. The rail 25 is a long columnar portion with the y-axis direction as the longitudinal direction, and is provided at a corner of the housing 20.

  In the present embodiment, the rail receiving portion 35 (that is, the protruding portions 35a and 35b) extends in the direction away from the lens holder 31 (the direction intersecting the moving direction of the lens holder 31). The width along the axis (axis parallel to the moving direction of the lens holder 31) becomes narrower. By adopting this configuration, when the lens holder 31 is moving along the y-axis in accordance with the driving of the piezo element 50, the lens holder temporarily rotates and the rail receiving portion 35 and the rail 25 come into contact with each other. Even so, the movement of the lens holder 31 is not hindered by the friction generated between them. That is, it is possible to effectively suppress an increase in the amount of friction generated between the lens holder 31 and the housing 20 and hinder the displacement of the lens holder 31.

  For example, when the lens holder 31 swings in the xz plane orthogonal to the y axis, the rail receiving portion 35 and the rail 25 may be in contact with each other. In this case, it is preferable that the contact area between the rail receiving portion 35 and the rail 25 is small. In the present embodiment, as described above, the rail receiving portion 35 has a narrow width along the y-axis as it extends in a direction away from the lens holder 31. As a result, even if the rail receiving portion 35 and the rail 25 are brought into contact with each other, the amount of friction generated between them can be reduced.

  Support plates 32 a and 32 b are integrally provided on the outer peripheral surface of the lens holder 31. The support plates 32 a and 32 b extend outward from the outer peripheral surface of the lens holder 31. Further, the support plates 32a and 32b are arranged at a predetermined interval in the y-axis direction. The support plates 32a and 32b are formed with openings into which the transmission shaft 51 is inserted. The support plates 32a and 32b may be fixed with an adhesive or the like as a separate body from the lens holder 31.

  The support plate 32a fixedly supports the transmission shaft 51. The opening formed in the support plate 32 a is slightly narrower than the diameter of the transmission shaft 51. The transmission shaft 51 can be fixed to the support plate 32a by fitting the transmission shaft 51 by applying pressure to the opening formed in the support plate 32a. The hole diameter of the support plate 32b is the same as that of the support plate 32a.

  By adopting the above-described configuration, the transmission shaft 51 can be tightly held by the support plates 32a and 32b. In other words, the degree of vibration transmission between the transmission shaft 51 and the support plates 32a and 32b can be increased. In this way, the lens holder 31 can be displaced efficiently.

  When adopting a method other than press-fitting, the same effect as described above can be obtained by appropriately selecting an adhesive. For example, it is preferable to employ a thermosetting epoxy adhesive.

  A shaft holding portion 40 is disposed between the support plates 32a and 32b. These assembling methods are arbitrary. For example, the transmission shaft 51 may be inserted into these members in a state where the shaft holding portion 40 is disposed between the support plates 32a and 32b.

  By disposing the shaft holder 40 between the support plates 32a and 32b, the movement range of the lens holder 31 can be regulated. However, the transmission shaft 51 may be supported by one of the support plate 32a and the support plate 32b without being limited to such two-point support.

  The shaft holding part 40 holds the transmission shaft 51 in a slidable state along the y axis. The shaft holding part 40 and the transmission shaft 51 are in frictional engagement with each other.

  As shown in FIG. 5, the shaft holding portion 40 includes a main body portion 41, a presser plate (plate member) 42, a spring (elastic body) 43, and a presser plate (plate member) 44. In the direction away from the transmission shaft 51, the presser plate 42, the spring 43, and the presser plate 44 are arranged in this order. The main body 41 has a space for receiving the transmission shaft 51. Further, the main body 41 has a space for accommodating the presser plate 42, the spring 43, and the presser plate 44.

  The presser plate 42 is a rectangular flat plate member. The spring 43 is a general coil spring. The presser plate 44 is a rectangular flat plate member.

  The presser plate 42, the spring 43, and the presser plate 44 are sequentially pushed into the main body 41. The presser plate 42, the spring 43, and the presser plate 44 are positioned by bonding and fixing the presser plate 44 to the main body 41. Specifically, the spring 43 is confined in the space of the main body 41 by the presser plate 44 and biases the holding plate 42 toward the transmission shaft 51. The presser plate 42 is urged toward the transmission shaft 51 by a spring 43. The transmission shaft 51 is urged inward by the spring 43 through the presser plate 42 and is held between the main body 41 and the presser plate 42. In other words, the transmission shaft 51 and the shaft holding portion 40 are in frictional engagement.

  The holding plate 42 is preferably made of a metal material. For example, the holding plate 42 may be formed of a metal material such as a zinc alloy or an aluminum alloy. Accordingly, it is possible to effectively suppress the generation of wear powder from the press plate 42 due to friction between the transmission shaft 51 and the press plate 42.

  The diameter of the spring 43 is substantially the same as or slightly smaller than the width of the presser plate 42. The specific configuration of the spring 43 is arbitrary, and other types of elastic bodies (plate springs, resin rubber, etc.) may be used. The main body 41 is manufactured by molding a resin with a mold. The holding plates 42 and 44 are manufactured by press molding of a metal plate or a resin plate.

  The main body 41 is preferably made of a metal material. When the main body 41 is made of resin, wear powder may be generated due to friction with the transmission shaft 51. In order to avoid the occurrence of such a problem, here, the main body 41 is manufactured by forming a zinc alloy. In addition, you may employ | adopt not only a zinc alloy but an aluminum alloy and another metal material.

  As shown in FIG. 5, the width along the axis Lx <b> 1 of the presser plate 44 is narrower than the width along the axis Lx1 of the presser plate 42. As a result, the spring 43 can be disposed at a position closer to the inner surface of the housing 20, and the camera module 100 can be downsized.

  The spring 43 urges the presser plate 42 in a direction forming 90 degrees with respect to the arrangement direction of the transmission shaft 51 as viewed from the lens holder 31. In other words, the spring 43 biases the presser plate 42 along the axis Lx2 that forms 90 degrees with respect to the axis Lx1 that coincides with the arrangement direction of the transmission shaft 51 as viewed from the lens holder 31. Thereby, the arrangement space of the shaft holding portion 40 can be effectively reduced, and the camera module 100 can be reduced in size. The angle formed by the axis Lx1 and the axis Lx2 is not limited to 90 degrees. The angle formed by the axis Lx1 and the axis Lx2 may be 45 to 135 degrees.

  Further description will be given with reference to FIGS.

  As shown in FIG. 6, the coil mounting board 90 includes a mounting board 91 and a set of coil chips (inductive elements) 95.

  The mounting substrate 91 is a flat plate member. A set of coil chips 95 is mounted on the mounting surface of the mounting substrate 91 as described above. The mounting board 91 is, for example, an epoxy board or a flexible wiring board. The mounting substrate 91 is attached to the housing 20 (this will be described later with reference to FIG. 8).

  A set of connection terminals 92 and a set of connection terminals 93 are provided on one side of the mounting substrate 91. Each connection terminal is a conductive pattern (for example, a metal pattern) formed on the mounting substrate 91.

  The set of coil chips 95 (95a, 95b) is mounted on the mounting surface of the mounting substrate 91. The coil chip 95 is a chip incorporating a coil (inductor, inductive element) that is an electronic element.

  The coil chip 95 is connected between the connection terminal 92 and the connection terminal 93. Specifically, the connection terminal 92 a is connected to one end of the coil chip 95 a via a wiring (wiring pattern) on the mounting substrate 91. The other end of the coil chip 95a is connected to the connection terminal 93a via a wiring on the mounting substrate 91. Similarly, the coil chip 95b is connected between the connection terminal 92b and the connection terminal 93b.

  The mounting substrate 91 has projecting portions 91a and 91b projecting upward (upper end side of the housing 20, object side) corresponding to the connection terminals 92a and 92b. The connection terminal 92a is provided on the protrusion 91a. The connection terminal 92b is provided on the protrusion 91b. Each protrusion 91a, 91b is provided with an opening. Conductive patterns that function as connection terminals 92a and 92b are formed in portions where the openings of the protrusions 91a and 91b are provided. The connection terminal 92a and the lead wire 52a are electrically connected by winding the tip of the lead wire 52a around the opening of the protruding portion 91a. Similarly, by winding the tip of the lead wire 52b around the opening of the protruding portion 91b, electrical contact between the lead wire 52b and the connection terminal 92b is ensured. It is assumed that the conductive wire is exposed from the coating at the tip of the lead wire 52. A specific method for making electrical contact between the lead wire 52 and the connection terminal 92 is arbitrary. Both may be fixed by soldering.

  The coil mounting board 90 shown in FIG. 6 is accommodated in the housing 20 as shown in FIG. As shown in FIG. 7, when the coil mounting board 90 is stored in the housing 20, the following state is obtained. In the range P1, the extraction terminal 82 and the connection terminal 93b are arranged. The connection terminal 92b is disposed in the range P2. The lead terminal 81 and the connection terminal 93a are arranged in the range P3. The connection terminal 92a is arranged in the range P4. The ranges P1 to P4 are ranges set sequentially on the Z axis.

  According to the attachment of the coil mounting substrate 90 to the housing 20, the connection terminal 93a and the lead terminal 81 are arranged to face each other. This makes it possible to easily ensure an electrical connection between the two. For example, the electrical contact between the connection terminal 93a and the lead terminal 81 is ensured by physical contact between them. Similarly, the electrical contact between the connection terminal 93b and the lead terminal 82 is ensured by the physical contact between them. Note that the connection terminal 93a and the lead terminal 81 may be fixed with a conductive material such as solder. The same applies to the connection terminal 93b and the lead terminal 82. As a result, the resistance of the electrical connection against impact or the like can be increased.

  According to the attachment of the coil mounting substrate 90 to the housing 20, the lead terminals 81 and 82 and the connection terminals 92a and 92b are alternately arranged. This effectively suppresses a direct connection between the lead terminals 81 and 82 and the connection terminals 92a and 92b, resulting in a short circuit state. Specifically, as described above, the extraction terminal 82, the connection terminal 93b, the extraction terminal 81, and the connection terminal 93a are arranged in this order in the Z-axis direction. By preventing a short circuit between the lead terminal 81 and the connection terminal 92a, the coil chip 95a can be more reliably interposed on the electrical path between them.

  As shown in FIG. 8, the coil mounting board 90 is housed in the housing 20. The housing | casing 20 is a box-shaped member which has the side wall 21 (21a-21d). On the inner side surface of the side wall 21c of the housing 20, a substrate storage portion 20p for storing the coil mounting substrate 90 is provided. The board housing part 20p has a wall part 20p1 that prevents the coil mounting board 90 from falling inward (to the lens holder 31 side). The interval between the wall portion 20p1 and the side wall 21c is set corresponding to the substrate thickness of the mounting substrate 91 of the coil mounting substrate 90.

  In addition, the attachment position of the coil mounting substrate 90 with respect to the housing | casing 20 is arbitrary. Considering that the piezo element 50 and the coil mounting substrate 90 are connected by the lead wire 52, the coil mounting substrate 90 may be disposed in the upper storage space of the housing 20 as in the piezo element 50.

  As shown in FIG. 8, the rail 25 is provided in the corner | angular part which the side wall 21b and the side wall 21c connect. The rail 25 extends from the housing 20 side to the lens holder 31 side. The end of the rail 25 on the housing 20 side is narrow, and the end of the rail 25 on the lens holder 31 side is wide. That is, the rail 25 has a narrow portion 25a and a wide portion 25b.

  The rail receiver 35 extends from the outer periphery of the lens holder 31 toward the housing 20 in a direction from the center (optical axis) on the lens holder 31 side toward the outer periphery. The rail receiving portion 35 has a pair of protruding portions 35a and protruding portions 35b. In this example, projections 35 a and 35 b are provided at positions facing the transmission shaft 51 fixed to the lens holder 31 via the center of the lens holder 31. The inner surfaces of the protrusions 35a and 35b are parallel to each other. When the camera module 100 is viewed from above, the protrusion 35a extends in a direction away from the lens holder 31 while maintaining a substantially constant width. The same applies to the protrusion 35b.

  The rail 25 is received by the rail receiving portion 35 with a predetermined interval. Specifically, the front end portion of the rail 25 is disposed with a predetermined interval between the protruding portion 35a and the protruding portion 35b.

  As shown in FIG. 8, when viewed from the moving direction of the lens holder 31, a width W <b> 15 where the rail 25 and the rail receiving portion 35 overlap in the lens holder radial direction is narrower than a width W <b> 16 between the rail 25 and the lens holder 31. By setting the widths W15 and W16 in this way, the amount of friction generated between the lens holder 31 and the housing 20 can be made as small as possible. The width W15 extends from the outer surface (the housing 20 side) to the inner side (lens holder 31 side) of the rail 25 extending from the inner side to the outer side (the surface facing the outer peripheral surface of the lens holder 31). This corresponds to the distance between the front end surface of the rail receiving portion 35 (the surface facing the inner surface of the housing 20). The width W16 corresponds to the distance between the outer peripheral surface of the lens holder 31 and the tip surface of the rail 25. W15 is preferably 0.05 to 0.3 mm. If the thickness is 0.3 mm or more, the contact area at the time of contact increases, and if it is 0.05 or less, the rail and the rail receiving portion may be in a pressure contact state when dropped. Strength retaining beam portions 26 are provided at corners between the side wall 21a and the side wall 21b of the housing 20. By providing the beam portion 26, it is possible to ensure the strength of the housing 20.

  FIG. 9 shows a schematic top view of the camera module 100. As shown in FIG. 9, the top view shape of the housing 20 is substantially square. The width W11 along the z-axis of the housing 20 is substantially equal to the width W12 along the x-axis of the housing 20. The lens holder 31 is disposed substantially at the center of the housing 20.

  FIG. 10 shows a schematic cross-sectional schematic view of the camera module 100 taken along the dotted line in FIG. As shown in FIG. 10, when the coil mounting board 90 is inserted into the board housing portion 20 p of the housing 20 and the coil mounting board 90 is held by the housing 20, the mounting board 91 of the coil mounting board 90 and The side wall 21c of the housing 20 is in surface contact. Thereby, the connection terminals 93a and 93b of the coil mounting substrate 90 can be brought into contact with the lead terminals 81 and 82, respectively. This also simplifies the operation when the connection terminals 93a and 93b are fixed to the lead terminals 81 and 82 by soldering or the like.

  With reference to FIGS. 11 and 12, a method of attaching the lead terminals 81 and 82 to the housing 20 will be described.

  As shown in FIG. 11, the metal plate (conductive plate) 80 includes a portion 81 to be a lead terminal 81, a portion 82 to be an electrode terminal, a linear depression 84, and a separation portion 85 in which the portion 81 and the portion 82 are connected. Have

  The portion 81 has a body portion 81b and a base portion 81c. The portion 82 has a trunk portion 81b and a base portion 81c. The trunk portion 81b is in an upright state with respect to the base portion 81c. The trunk portion 82b is also in a standing state with respect to the base portion 82c. The thickness of the portions 81 and 82 is sufficiently thinner than the thickness of the separation portion 85. Thus, the portions 81 and 82 and the separation portion 85 can be easily separated by using the linear depression 84 as a cutting line.

  As schematically shown in FIG. 11, the metal plate 80 is attached to the housing 20. The housing 20 is provided with a receiving portion that receives the metal plate 80. After attaching the metal plate 80 to the housing 20, as schematically shown in FIG. 12, the detaching portion 85 is cut off from the other portions. In this way, the lead terminals 81 and 82 can be easily attached to the housing 20.

  As shown in FIG. 13, the receiving portion 22 of the lead terminals 81 and 82 is provided on the inner peripheral surface of the housing 20. Specifically, as schematically shown in FIG. 13, the receiving portion 22 a receives the lead terminal 82. The receiving part 22 b receives the lead terminal 81.

  Note that the partition wall 21e of the housing 20 is provided with openings through which the lead terminals 81 and 82 are inserted. As illustrated in FIG. 13, the partition wall 21 e is a plate-like portion that separates the upper space and the lower space of the housing 20. The partition wall 21e has an optical opening at a position corresponding to the optical axis AX of the lenses OL1 to OL3. More specifically, the partition wall 21e has a rectangular opening OP2 corresponding to the imaging region 12a of the image sensor 12.

  In addition, the timing which attaches the extraction | drawer terminals 81 and 82 with respect to the housing | casing 20 is arbitrary. Moreover, the timing which attaches the coil mounting board | substrate 90 with respect to the housing | casing 20 is arbitrary.

  For example, the camera module may be assembled as follows. First, the metal plate 80 is attached to the housing 20. Next, the removal part 85 of the metal plate 80 is cut out. Next, the coil mounting substrate 90 is attached to the housing 20. Next, the lens unit 30 is attached to the housing 20. Next, electrical contact between the mounting substrate 91 and the piezoelectric element 50 is ensured. Specifically, the connection terminal 92a of the mounting substrate 91 and the electrode terminal 50a of the piezo element 50 are connected by a lead wire 52a. Further, the connection terminal 92b of the mounting substrate 91 and the electrode terminal 50b of the piezo element 50 are connected by a lead wire 52b. Next, as necessary, a set of connection terminals 93 of the mounting substrate 91 are fixed to the lead terminals 81 and 82, respectively. Specifically, the connection terminal 93 a of the mounting substrate 91 is soldered to the extraction terminal 81. Similarly, the connection terminal 93 b of the mounting substrate 91 is soldered to the extraction terminal 82. Next, the housing 20 is mounted on the wiring board 10. In addition, before mounting the housing | casing 20 with respect to the wiring board 10, the laminated body of the image sensor 12 and the transparent substrate 13 shall be arrange | positioned on the wiring board 10. FIG. The order of the above steps can be changed as appropriate.

  In the present embodiment, the coil mounting substrate 90 is attached to the housing 20. This makes it possible to easily connect a coil between the electrode terminal 50a (50b) of the piezo element 50 and the lead terminal 81 (82) provided in the housing 20.

  By attaching the coil mounting board 90 to the housing 20, the connection terminals 93 a and 92 b of the coil mounting board 90 can be arranged to face the lead terminals 81 and 82 provided in advance in the housing 20. This makes it possible to easily ensure an electrical connection between the two.

  Protruding portions 91 a and 91 b around which the lead wire 52 can be wound are provided on the upper side portion of the coil mounting substrate 90 that is held with respect to the housing 20. Thereby, the electrical connection between the lead wire 52 and the mounting substrate 91 can be easily ensured.

  FIG. 14 is a schematic cross-sectional configuration diagram of the camera module 100. As shown in FIG. 14, the lens holder 31 holds the lenses OL1 to OL3. The lens OL1 is disposed in the lens holder 31 through an alignment process. The lenses OL2 and OL3 are arranged in the lens holder 31 without going through the alignment process. That is, the lens OL1 is a lens that requires higher positional accuracy than the lenses OL2 and OL3.

  The method of incorporating the lenses OL1 to OL3 into the lens holder 31 is arbitrary. For example, the lens OL3 and the lens OL2 are laminated in this order, the lens OL1 is aligned on the lens OL2, the lens OL3, the lens OL2, and the lens OL1 are bonded and fixed, and then the laminated body of the lenses OL1 to OL3. Is preferably press-fitted into the lens holder 31. The lenses OL1 to OL3 may be incorporated into the lens holder 31 by a method other than press fitting.

  Each width shown in FIG. 14 is as follows. W41: 1 mm, W42: 1 mm, W43: 2 mm, W44: 6 mm, W45: 3 mm. The piezo element 50 is a rectangular parallelepiped having a side of about 1 mm. Regarding the size of the piezo element 50, it is preferable to set it to ½ or less of the length of the transmission shaft 51.

  With reference to FIG. 15, a supplementary explanation will be given regarding the electrical wiring relationship in the housing. As shown in FIG. 15, the electrode terminal 50a of the piezo element 50 is connected to the connection terminal 92a of the mounting substrate 91 via the lead wire 52a. The connection terminal 92a is connected to one end of the coil chip 95a. The other end of the coil chip 95a is connected to the connection terminal 93a. The connection terminal 93a is connected to the lead terminal 81. The electrode terminal 50b of the piezo element 50 is connected to the connection terminal 92b of the mounting substrate 91 via the lead wire 52b. The connection terminal 92b is connected to one end of the coil chip 95b. The other end of the coil chip 95b is connected to the connection terminal 93b. The connection terminal 93b is connected to the lead terminal 82.

  As is clear from the above description, in this embodiment, the coil chip 95a is connected between the lead terminal 81 provided on the housing 20 and the electrode terminal 50a of the piezo element 50. Similarly, the coil chip 95 b is connected between the lead terminal 82 provided on the housing 20 and the electrode terminal 50 b of the piezo element 50.

  By adopting this configuration, the manufacturer of the camera module 100 can incorporate a coil chip 95 with appropriate characteristics. In other words, even if the drive circuit of the piezo element 50 is not incorporated on the manufacturer side of the camera module, and the drive circuit of the piezo element 50 is incorporated on the purchaser side, the purchaser side must select excessive coils. Will not be incurred. This makes it possible to realize a camera module that is user-friendly and has high-performance operating characteristics.

  As will be apparent from the description below, the operating characteristics of the camera module 100 are improved by connecting the coil chip 95 to the piezo element 50. However, unless the drive circuit of the camera module 100 is appropriately configured, it is difficult to ensure the operation characteristics of the camera module 100 as intended.

  As described in the introduction, when an additional circuit element such as an inductor is connected to the piezo element, the operating characteristics of the camera module presented by the camera module manufacturer can be easily obtained by the selected inductor. Sometimes not. Since there are many types of inductors, it is often not known through trial and error operation verification which inductor can be used to ensure the intended operating characteristics of the camera module. In addition, not only the characteristics of individual inductors but also the overall characteristics of the drive circuit may vary depending on the compatibility between circuit elements.

  In the present embodiment, as described above, the coil chip 95a is connected between the lead terminal 81 provided on the housing 20 and the electrode terminal 50a of the piezo element 50. Similarly, the coil chip 95 b is connected between the lead terminal 82 provided on the housing 20 and the electrode terminal 50 b of the piezo element 50. By adopting this configuration, it becomes possible for the camera module manufacturer to incorporate a coil with appropriate characteristics, and the camera module purchaser does not need to separately select and mount the coil. .

  By making it possible to ship the camera module by incorporating circuit elements that can greatly affect the operating characteristics of the camera module in advance, the purchaser of the camera module only needs to prepare the remaining part of the camera module drive circuit. Become. Accordingly, it is possible to easily realize the operation characteristics of the camera module presented on the camera module manufacturer side on the camera module purchaser side.

  Hereinafter, the drive circuit of the camera module will be described with reference to FIGS.

  As shown in FIG. 16, the drive circuit 200 includes a controller 201, transistors (switches, switching units, switching elements, circuit elements) Q1 to Q4, coils (inductive elements, inductors, circuit elements) L1, L2, and piezoelectric elements. Has PZ. Note that the piezo element PZ corresponds to the piezo element 50. The coils L1 and L2 correspond to the coil chip 95.

  The transistors Q1 and Q3 are P-channel MOSFETs (Metal Oxide Semiconductor Field Effect Transistors). Transistors Q2 and Q4 are N-channel MOSFETs.

  The transistors Q1 and Q4 are connected in series between the power supply potential VDD and the ground potential GND. The transistors Q3 and Q2 are connected in series between the power supply potential VDD and the ground potential GND.

  When a node to which the drive voltage + E is supplied from the power supply potential VDD is a node a and a node to which the ground potential is supplied from the ground potential GND is a node b, the following connection relationship is established.

  The source terminal of transistor Q1 is connected to node a. The drain terminal of the transistor Q1 is connected to the drain terminal of the transistor Q4. The source terminal of transistor Q4 is connected to node b.

  The source terminal of transistor Q3 is connected to node a. The drain terminal of the transistor Q3 is connected to the drain terminal of the transistor Q2. The source terminal of transistor Q2 is connected to node b.

  The transistors Q3 and Q2 connected in series between the power supply potential VDD and the ground potential GND are connected in parallel to the transistors Q1 and Q4 connected in series between the power supply potential VDD and the ground potential GND.

  Note that the source terminal of the transistor Q1 and the source terminal of the transistor Q3 are connected to the node a. The source terminal of the transistor Q4 and the source terminal of the transistor Q2 are connected to the node b.

  A node between the drain terminal of the transistor Q1 and the drain terminal of the transistor Q4 is referred to as a node c (first output terminal). A node between the drain terminal of the transistor Q3 and the drain terminal of the transistor Q2 is a node d (second output terminal). The node c is connected to one electrode terminal of the piezo element PZ via the coil L1. The node d is connected to the other electrode terminal of the piezo element PZ via the coil L2.

  A wiring connecting the node c and the node d is a coupling line. The drive circuit 200 is a so-called H bridge circuit.

  A path from the drain terminal of the transistor Q1 to the piezo element PZ is defined as a first output stage. A coil L1 is provided in the first output stage. The first terminal of the coil L1 is connected to the drain terminal of the transistor Q1 and the drain terminal of the transistor Q4, and the second terminal of the coil L1 is connected to the first terminal of the piezo element PZ.

  A path from the drain terminal of the transistor Q3 to the piezo element PZ is defined as a second output stage. A coil L2 is provided at the second output stage. The first terminal of the coil L2 is connected to the drain terminal of the transistor Q3 and the drain terminal of the transistor Q2, and the second terminal of the coil L2 is connected to the second terminal of the piezo element PZ. Note that the inductance of the coil L1 is equal to the inductance of the coil L2.

  The output terminal CT2 of the controller 201 is connected to the gate terminal (control terminal) of the transistor Q1. The output terminal CT4 of the controller 201 is connected to the gate terminal of the transistor Q2. The output terminal CT1 of the controller 201 is connected to the gate terminal of the transistor Q3. The output terminal CT3 of the controller 201 is connected to the gate terminal of the transistor Q4.

  The controller 201 controls the operation state (ON / OFF) of the transistors Q1 to Q4. The controller 201 outputs a control signal Sc1 to the gate terminal of the transistor Q1. The controller 201 outputs a control signal Sc2 to the gate terminal of the transistor Q2. The controller 201 outputs a control signal Sc3 to the gate terminal of the transistor Q3. The controller 201 outputs a control signal Sc4 to the gate terminal of the transistor Q4.

  The transistors Q1 and Q3 are turned off when an H level (high level) control signal is supplied from the controller 201, and are turned on when an L level (low level) control signal is supplied from the controller 201. The transistors Q2 and Q4 are turned on when an H level (high level) control signal is supplied from the controller 201, and are turned off when an L level (low level) control signal is supplied from the controller 201.

  The transistor Q1, the coil L1, and the transistor Q2 constitute a first drive circuit that applies a drive voltage from one side of the piezo element PZ. The transistor Q3, the coil L2, and the transistor Q4 constitute a second drive circuit that applies a drive voltage from the other side of the piezo element PZ (that is, from the reverse direction).

  FIG. 17 shows a timing chart showing an operation sequence of the drive circuit 200. In the period A, the control signal Sc3 and the control signal Sc2 are at the H level, and the control signal Sc1 and the control signal Sc4 are at the L level. At this time, the transistor Q1 and the transistor Q2 are turned on, and the transistor Q3 and the transistor Q4 are turned off. At this time, as schematically shown in FIG. 18, a voltage is applied to the piezo element PZ from one direction. More specifically, a current flows from the power supply potential VDD to the piezo element PZ via the transistor Q1 and the coil L1, and the piezo element PZ is charged. The electric charge accumulated in the piezo element PZ is discharged to the ground potential GND through the coil L2 and the transistor Q2.

  In the period B, the control signal Sc1 and the control signal Sc4 are at a high level, and the control signal Sc3 and the control signal Sc2 are at a low level. Transistors Q3 and Q4 are turned on, and transistors Q1 and Q2 are turned off. At this time, as schematically shown in FIG. 19, a voltage is applied to the piezo element PZ from the reverse direction. More specifically, a current flows from the power supply potential VDD to the piezo element PZ via the transistor Q3 and the coil L2, and the piezo element PZ is charged. Further, the electric charge accumulated in the piezo element PZ is discharged to the ground potential GND through the coil L1 and the transistor Q4. Note that the period A is set shorter than the period B.

  The displacement of the lens holder 31 will be described with reference to FIGS. As shown in FIG. 20, the lens holder 31 is displaced in the forward direction as the voltage Vs across the piezo element PZ (piezo element 50) changes between positive and negative. In FIG. 20, the displacement of the lens holder 31 is indicated by an arrow. That is, the lens holder 31 is displaced between the times t1 and t2, and is not displaced between the times t2 and t3. The same applies to other periods.

  As shown in FIG. 21, the expansion and contraction of the piezo element 50 and the displacement of the lens holder 31 are linked. Between the times t1 and t2, the voltage Vs across the piezo element 50 rises steeply. In response to the sudden rise in voltage, the piezo element 50 expands rapidly. When the piezo element 50 changes suddenly, the transmission shaft 51 slides with respect to the shaft holding portion 40. Thereby, the piezo element 50, the transmission shaft 51, and the lens holder 31 are displaced with respect to the shaft holding portion 40.

  On the other hand, between the times t2 and t3, the voltage Vs across the piezo element 50 falls slowly. In response to the slow fall of the voltage, the piezo element 50 contracts relatively slowly. At this time, the change of the piezo element 50 does not generate a force for displacing the transmission shaft 51, and the transmission shaft 51 remains in place. The lens holder 31 together with the transmission shaft 51 remains in place.

  Thus, when the piezo element 50 is rapidly expanded, the lens holder 31 is displaced with respect to the shaft holding portion 40. In other words, the lens holder 31 is not displaced with respect to the shaft holder 40 when the piezo element 50 contracts slowly.

  In this case, in order to displace the lens holder 31 efficiently, the pulse width of the switching pulse SP corresponding to the control signal supplied from the controller 201 to the transistors Q1 to Q4 is narrowed, so that the piezo element PZ is shortened in a short time. It can be said that it is good to stretch.

  Considering that it is necessary to ensure the discharge time of the current accumulated in the piezo element PZ, it can be said that the duty ratio of the switching signal should be set small.

  In this embodiment, the coil L1 is connected to the first output stage (between the node c and the piezo element PZ), and the coil L2 is connected to the second output stage (between the node d and the piezo element PZ). Therefore, even when a drive voltage is applied from one side of the piezo element PZ in the first drive circuit (transistor Q1, coil L1, transistor Q2), the piezo element PZ in the second drive circuit (transistor Q3, coil L2, transistor Q4). Even when a drive voltage is applied from the other side (ie, from the opposite direction), a gain is obtained, and the drive signal level can be made higher than the power supply voltage level E in a pseudo manner. The reason will be described next.

  Since inductive elements (coils L1, L2) are provided in the first and second output stages in this embodiment, the first drive circuit and the second drive circuit are each represented by an equivalent circuit shown in FIG. . In FIG. 22, R0 represents the on-resistance of the transistors Q1-Q4. The on-resistance of each of the transistors Q1-Q4 is generally 1 [Ω] or less, depending on the element characteristics. L represents the inductance of the inductive element (91, 92). Cp represents the capacitance value of the piezo element PZ.

  This equivalent circuit is a configuration of a filter circuit having a peak at a resonance point, and constitutes a so-called secondary LPF (Low Pass Filter). The resonance point and fc (cutoff frequency) of the LPF are determined by the resonance of L and Cp. By selecting the drive frequency and L in accordance with R0 and Cp, a gain of several dB can be obtained within the drive frequency band, and the drive signal level can be increased in a pseudo manner.

  FIG. 23 shows the simulation results when Ro = 0.1 (Ω), Cp = 30 (nF), and L = 6.8 (uH). In FIG. 23, the frequency range is shown in the range of 1 kHz to 10 MHz. As shown in FIG. 23, the gain is zero until the drive frequency is around 100 kHz. However, when the drive frequency exceeds 100 kHz, the gain starts to increase, and the highest gain is obtained by resonance between 300 kHz and 400 kHz. Then, when the resonance point is passed, the gain starts to decrease rapidly, becomes zero at around 500 kHz, and further decreases as the driving frequency increases.

  The drive frequency band is preferably selected so that the gain is greater than zero. In the example of FIG. 23, it is preferable to select a drive frequency between 100 kHz and 500 kHz as indicated by a section f1 in the figure.

  Thereby, even when the piezoelectric element PZ is downsized and the power supply voltage E is lowered, a pseudo high voltage can be applied to the piezoelectric element PZ, and the displacement vibration characteristics of the piezoelectric actuator can be improved. be able to.

  When the piezoelectric element becomes smaller and the capacitance value of the piezoelectric element becomes smaller, the value of the inductance L and the drive frequency are selected accordingly, so that even a small and low-voltage piezoelectric actuator can be operated. Can be maintained.

  Further, as the driving frequency, the gain is zero or more, but it is preferable to exclude the frequency before and after the frequency at the resonance point. When driving frequencies before and after the resonance point are selected, the gain varies greatly if the frequency is slightly shifted. As a result, there is a risk that the variation in operating characteristics from product to product becomes very large. Therefore, it is preferable to select the driving frequency to be selected from the sections f2 and f3 while avoiding the section f4 in FIG. For example, the frequency range f4 to be avoided may be 10% before and after the resonance point frequency, and may further be 30% before and after the resonance point frequency.

  Further, it is preferable to select a driving frequency that is lower than the frequency of the resonance point and has a gain greater than zero. FIG. 24 is a diagram in which a region in the middle of the gain increasing toward the resonance point peak in FIG. 23 is extracted. In FIG. 24, the frequency range is 1 kHz to 300 kHz. It is preferable to select the drive frequency in a region in which the gain increases toward the resonance point peak, as in a region surrounded by a circle in FIG. Even after the resonance point peak (for example, section f3 in FIG. 23), the gain is greater than zero, but since the decrease curve is steep, the gain changes greatly if the drive frequency deviates even slightly from the set value.

  In this regard, if the gain is in the region where the gain is increasing toward the resonance point peak (section f5 in FIG. 24), the curve is gentle, and variations among products can be suppressed. As shown in FIG. 24, when the drive frequency is 150 kHz, a gain of about 2 dB can be obtained.

  FIG. 25 and FIG. 26 show the results of simulation with the inductance L of the inductive element changed. In FIG. 25 and FIG. 26, a region where the gain is increasing toward the resonance point peak is circled, and the drive frequency is selected within the circled range. In FIG. 25, when the drive frequency is 150 kHz, a gain of about 3 dB can be obtained. In FIG. 26, when the drive frequency is 150 kHz, a gain of about 6 dB can be obtained.

  By selecting the drive frequency as described above, a pseudo high voltage can be applied to the piezo element PZ, and the displacement vibration characteristics of the piezoelectric actuator can be improved.

  In the type of drive device in which the piezoelectric element or the drive shaft is fixed to the fixed side member, it is necessary to select a drive frequency so as to avoid resonance with the fixed side member. The driving frequency band cannot be set widely, and the driving frequency can be selected only within a narrow range in which resonance with the fixed member can be surely avoided.

  In this regard, in the present embodiment, the piezo element 50 and the transmission shaft 51 are not directly fixed to the fixed member, and therefore, the piezo element 50 and the transmission shaft 51 are not considered without considering resonance with the fixed member. The driving frequency for the piezo element PZ can be set appropriately only by taking into account the inherent resonance derived from Therefore, as described above, the drive frequency can be selected from the range where the gain can be obtained.

  Further, as shown in FIG. 27, the harmonic component of the drive signal can be suppressed. For example, it can be seen that suppression of about −10 dB is effective for the harmonic component of 400 kHz, and further higher harmonic components are further suppressed. That is, it can be seen that the high-frequency component mixed in the drive signal can be sufficiently suppressed.

  For example, high-frequency noise may be mixed in the drive voltage via the power line. FIG. 28 shows an example of the drive voltage in which the power line noise is added. If such noise enters, the movement of the piezoelectric actuator stops intermittently, which causes a problem that the operation becomes unstable. In this respect, in the drive circuit 200 of the present embodiment, the harmonic noise can be suppressed by the filter effect as shown in FIG. 29, and the operation of the piezoelectric actuator can be stabilized.

  Further, when a piezoelectric actuator is actually incorporated into a product, the wiring length of the output stage (wiring from the nodes c and d to the piezo element PZ) may become long. In addition, the wiring length of the output stage may vary depending on the product. In this case, since the wiring inductance varies depending on the wiring length, there is a possibility that the operation may vary due to unexpected resonance.

  In this embodiment, coil chips 95 (coils L1 and L2) as inductive elements are provided in advance in the output stage. The inductance of the coil chip 95 is sufficiently larger than the wiring inductance. Therefore, even if the wiring length is different, the inductance exceeding the effect of the coil chip 95 is not held, so that the drive control of the camera module can be stabilized. For example, there is no possibility of variations in the operation of the piezoelectric actuator due to unexpected resonance, and the operational stability of the camera module can be improved.

  In the present embodiment, the two coils L1 and L2 are operated with the piezo element PZ interposed between when the voltage is applied by the first drive circuit and when the voltage is applied by the second drive circuit. Yes. As a result, the back electromotive force acts on both the positive side and the negative side, and an effect of amplifying the drive voltage both on the positive side and the negative side can be obtained, and a large amplification effect can be obtained efficiently.

(Modification 1)
As a modification of the above embodiment, an example in which the arrangement positions of the coils L1 and L2 are changed will be described. A driving circuit 200 shown in FIG. 30 will be described as a first modification. In FIG. 30, a connection node between the drain terminal of the transistor Q1 and the drain terminal of the transistor Q4 is a node c. The node c is connected to the first electrode of the piezo element PZ. A connection node between the drain terminal of the transistor Q3 and the drain terminal of the transistor Q2 is a node d. The node d is connected to the second electrode of the piezo element PZ.

  In the first modification, the coil L1 is provided between the drain terminal of the transistor Q1 and the node c, and the coil L2 is provided between the drain terminal of the transistor Q3 and the node d. Also in this configuration, the coil L1 is in the first output stage, and the coil L2 is in the second output stage. Therefore, as in the first embodiment, the second drive circuit (transistor Q3, coil) can be applied even when a drive voltage is applied from one side of the piezo element PZ in the first drive circuit (transistor Q1, coil L1, transistor Q2). Even when a drive voltage is applied from the other side of the piezo element PZ (ie, from the opposite direction) by the transistor L4 and the transistor Q4), a gain can be obtained and the drive signal level can be made higher than the power supply voltage level E in a pseudo manner.

(Modification 2)
Modification 2 will be described with reference to FIG. Modification 2 is a modification that assumes a case in which a portion other than the piezo element PZ of the drive circuit 200 is configured by one chip.

  The drive circuit 200 according to Modification 2 further includes a transistor Q5 and a transistor Q6 in addition to the circuit elements shown in the above-described embodiment. Transistors Q5 and Q6 are N-channel MOSFETs.

  The drain terminal of the transistor Q5 is connected to the first electrode terminal of the piezo element PZ, and the source terminal of the transistor Q5 is connected to the ground potential GND (ground power supply). The drain terminal of the transistor Q6 is connected to the second electrode terminal of the piezo element PZ, and the source terminal of the transistor Q6 is connected to the ground potential GND (ground power supply).

  A control signal Sc4 common to the transistor Q4 is supplied to the gate terminal of the transistor Q5. A control signal Sc2 common to the transistor Q2 is supplied to the gate terminal of the transistor Q6.

  That is, the transistor Q5 and the transistor Q4 perform the same operation, and the transistor Q6 and the transistor Q2 perform the same operation.

  In this configuration, when the control signals Sc1-Sc4 are sent in the timing chart shown in FIG. 17, the main operation is the same as that described in the first embodiment, and the same effect is obtained.

  In the drive circuit 200 shown in the first embodiment, when a drive voltage is applied from one side of the piezo element PZ in the first drive circuit (transistor Q1, coil L1, transistor Q2), the piezo element PZ is passed through the transistor Q2. A GND potential was applied. On the other hand, in the second modification, the GND potential is applied to the piezoelectric element through the transistor Q6 that operates in the same manner as the transistor Q2 (see FIG. 32).

  In this case, the coil L2 is not included in the current path, but the action described above is sufficiently obtained by including the coil L1 on the voltage application side in the path, and the drive signal level is increased in a pseudo manner. Can do.

  Similarly, in the drive circuit 200 shown in the first embodiment, when a drive voltage is applied from the other side of the piezo element PZ (that is, from the reverse direction) in the second drive circuit (transistor Q3, coil L2, transistor Q4), A GND potential is applied to the piezo element PZ via the transistor Q4. On the other hand, in the modified example 2, the GND potential is applied to the piezo element PZ through the transistor Q5 that operates in the same manner as the transistor Q4 (FIG. 33).

  In this case, the coil L1 is not included in the current path, but the action described above is sufficiently obtained by including the coil L2 on the voltage application side in the path, and the drive signal level is increased in a pseudo manner. Can do.

  Next, further description will be given with reference to FIGS. 34 and 35.

  The camera module 100 is mounted in a mobile phone 190 shown in FIG. The mobile phone 190 has an upper body 191, a lower body 192, and a hinge 193. The upper main body 191 and the lower main body 192 are both plastic flat members and are connected via a hinge 193. The upper body 191 and the lower body 192 are configured to be opened and closed by a hinge 193. When the upper body 191 and the lower body 192 are closed, the mobile phone 190 becomes a flat plate member in which the upper body 191 and the lower body 192 are overlapped.

  The upper body 191 has a display unit 194 on its inner surface. The display unit 194 displays information (name, phone number) for identifying the called party, address information stored in the storage unit of the mobile phone 190, and the like. A liquid crystal display device is incorporated under the display portion 194.

  The lower main body 192 has a plurality of buttons 195 on its inner surface. The operator of the mobile phone 190 operates the button 195 to open the address book, make a call, set the manner mode, and operate the mobile phone 190 as intended. The operator of the mobile phone 190 activates the camera module 100 in the mobile phone 190 based on operating this button 195.

  With reference to FIG. 35, a system configuration (configuration of the actuator drive unit) for operating the camera module 100 will be described. As shown in FIG. 35, the output of the image acquisition unit 180 is connected to the controller 181. The output of the controller 181 is connected to a drive voltage generation circuit (drive voltage supply unit) 182. The output of the drive voltage generation circuit 182 is connected to the vibration source 183. The image acquisition unit 180 is equivalent to the image sensor 12 described above. The vibration source 183 is equivalent to the piezo element 50 described above. The drive circuit 200 described above corresponds to a circuit including the drive voltage generation circuit 182 and the vibration source 183.

  The controller 181 is a CPU incorporated in the mobile phone 190, and generates various commands by executing a program. The controller 181 activates the function of the camera module according to the operation of the mobile phone 190 by the operator.

  The controller 181 has a function of adjusting the moving speed of the lens holder 31. The controller 181 determines whether or not the lens holder 31 is in the in-focus position based on processing for the image transmitted from the image acquisition unit 180, and in order to bring the lens holder 31 into the in-focus state, The moving direction and moving amount of the holder 31 are calculated. When the lens holder 31 is moved from a position away from the in-focus position to the in-focus position, the controller 181 controls the drive voltage generation circuit 182 so that the lens holder 31 moves at high speed. When the lens holder 31 is moved to the in-focus position within a distance close to the in-focus position, the controller 181 controls the drive voltage generation circuit 182 so that the lens holder 31 moves at a low speed. The drive voltage generation circuit 182 supplies a sawtooth drive voltage to the vibration source 183 in accordance with a control signal supplied from the controller 181. The specific configuration of the drive voltage generation circuit 182 is arbitrary. The vibration source 183 expands and contracts according to the sawtooth drive voltage supplied from the drive voltage generation circuit 182 to generate vibration. The lens holder 31 is displaced toward the object side or the image sensor side along the optical axis AX according to the vibration generated by the vibration source 183. The optical axes AX of the lenses OL1 to OL3 intersect perpendicularly with the front surface of the image sensor 12.

[Second Embodiment]
The second embodiment will be described with reference to FIGS. FIG. 36 is a schematic exploded perspective view of the camera module 100. FIG. 37 is a schematic partial perspective view of the camera module 100 before the coil mounting substrate 90 is arranged. FIG. 38 is a schematic partial perspective view of the camera module 100 after the coil mounting substrate 90 is arranged. FIG. 39 is a schematic perspective view of the coil mounting board 90. FIG. 40 is a schematic diagram showing a wiring pattern formed on the coil mounting board 90. FIG. 41 shows a coil mounting board 90 according to a modification.

  In the present embodiment, unlike the above-described embodiment, a conductive pattern is formed on the mounting substrate 91, thereby forming a coil. Even in such a case, the same effect as described in the above-described embodiment can be obtained. In this embodiment, a free space for the coil chip 95 can be secured in the housing 20. This makes it easy to reduce the size of the housing 20.

  As shown in FIGS. 36 to 38, the mounting substrate 91 is disposed in the housing 20 so as to be in surface contact with the inner side surface of the side wall 21c of the housing 20 as in the above-described embodiment. By attaching the coil mounting substrate 90 to the housing 20, as described in the first embodiment, the lead terminals 81 and 82 and the connection terminals 93a and 93b are arranged to face each other, and the electrical connection between them can be easily secured. be able to. Further, since the connection terminal 93b, the connection terminal 92b, the connection terminal 93a, and the connection terminal 93a are sequentially arranged along one side of the mounting substrate 91, as described in the first embodiment, the connection terminals 92 adjacent to each other. And a short circuit between the connection terminals 93 can be suppressed.

  The width of the mounting substrate 91 in the z-axis direction is slightly narrower than the distance between the side wall 21b and the side wall 21d of the housing 20. Therefore, the coil mounting board 90 can be easily arranged in the housing 20.

  The coil mounting substrate 90 is preferably attached to the side wall 21 of the housing 20 where the beam portion 26 is not provided. As a result, the area of the coil mounting substrate 90 can be secured wider, and it is easy to secure sufficient inductance.

  The coil mounting board 90 is preferably attached to the side wall 21 of the housing 20 where the piezo element 50 is not disposed in the vicinity. By attaching the coil mounting substrate 90 to a place where there is a space in the housing 20, it is possible to effectively suppress the size of the housing 20 from increasing in the z-axis direction.

  A method for fixing the coil mounting board 90 to the housing 20 is arbitrary. For example, the housing 20 may be provided with a structure that prevents the coil mounting board 90 from falling inward. The coil mounting substrate 90 may be fixed to the housing 20 by soldering between the lead terminals 81 and 82 and the connection terminal 93.

  As shown in FIG. 39, a pattern wiring region 90p is provided on the main surface of the mounting substrate 91 of the coil mounting substrate 90. As shown in FIG. 40, the conductive layer is patterned in the pattern wiring region 90p. When the drawing is viewed from the front, the conductive wire 90q extends in the right lateral direction of the mounting board with the connection terminal 92a as a base point. Next, the conductive line 90q extends in the vertically downward direction. Next, the conductive line 90q is folded back and extends in the vertical upward direction with a certain distance from adjacent conductive lines. Next, the conductive line 90q is folded back and extends in a vertically downward direction with a certain distance from adjacent conductive lines. The conductive wire 90q is repeatedly extended and folded to constitute a winding as a whole. In this way, the coil composed of the wiring pattern is mounted on the mounting substrate 91.

  The conductive wire 90q may be formed in the inner layer of the mounting substrate 91 or may be formed on the surface of the mounting substrate 91. By drawing the conductive wire 90q in the inner layer of the mounting substrate 91, the coil can be protected in the mounting substrate 91. Thereby, it is possible to effectively suppress the function of the coil from being impaired due to the influence of dust or the like.

  It is assumed that a coil is connected between the connection terminal 92b and the connection terminal 93b by a conductive wire as in the case between the connection terminal 92a and the connection terminal 93a. For example, a coil connected between the connection terminal 92a and the connection terminal 93a is configured with a wiring pattern on one main surface of the mounting substrate 91, and the connection terminal 92b and the connection terminal are formed on the other main surface of the mounting substrate 91. What is necessary is just to comprise the coil connected between 93b with a wiring pattern.

  When the coil is formed with the wiring layer in the mounting substrate 91, the coil connected between the connection terminal 92 a and the connection terminal 93 a is configured with a wiring pattern on one main surface side of the wiring substrate 10. On the other main surface side, a coil connected between the connection terminal 92b and the connection terminal 93b may be configured with a wiring pattern.

  FIG. 41 shows a coil mounting board 90 according to a modification. As shown in FIG. 41, connection terminals 93 may be arranged. In this case, the same effect as that of the present embodiment can be obtained. The arrangement position of the connection terminal 93 only needs to correspond to the arrangement position of the lead terminals 81 and 82. 41, when the connection terminal 93 is provided on the lower side of the mounting substrate, the height of the body 81b of the lead terminal 81 (the body 81b) is prevented in order to prevent a short circuit between the connection terminal 92 and the connection terminal 93. (Length in the y-axis direction) should be reduced. As is apparent from this modification, the positions where the connection terminals 92 and 93 are provided can be changed as appropriate.

[Third Embodiment]
The third embodiment will be described with reference to FIGS. 42 to 46. FIG. 42 is a schematic exploded perspective view of the camera module 100. FIG. 43 is a schematic partial perspective view of the camera module 100 before the coil mounting substrate 90 is arranged. FIG. 44 is a schematic partial perspective view of the camera module 100 after the coil mounting board 90 is arranged. FIG. 45 is a schematic perspective view of the coil mounting board 90. FIG. 46 shows a coil mounting board 90 according to a modification.

  In the present embodiment, unlike the second embodiment, the mounting substrate 91 of the coil mounting substrate 90 is configured by bending a plate-like member. In such a case, the same effects as those described in the first and second embodiments can be obtained. Also in the present embodiment, a free space for the coil chip 95 can be secured in the housing 20. This makes it easy to reduce the size of the housing 20.

  As shown in FIGS. 42 to 44, the mounting substrate 91 of the coil mounting substrate 90 has a shape in which a plate-like member is bent. The coil mounting board 90 is housed in the housing 20 in the same manner as in the above embodiment. The point where the electrical connection between the terminals is secured is the same as in the above-described embodiment.

  The mounting substrate 91 includes a flat plate portion 91m extending in the z-axis direction, a flat plate portion 91n extending in the x-axis direction, and a connecting portion 91z that connects the flat plate portion 91m and the flat plate portion 91n. The flat plate portion 91 m is in surface contact with the inner side surface of the side wall 21 c of the housing 20. The flat plate portion 91n is in surface contact with the inner side surface of the side wall 21b of the housing.

  As shown in FIG. 45, a pattern wiring region 90 p is formed on the inner side surface of the mounting substrate 91. Conductive lines are routed in the pattern wiring region 90p in the same manner as described in the second embodiment.

  As is apparent from the above description, in the present embodiment, the mounting substrate 91 is bent corresponding to two adjacent surfaces included in the four surfaces of the housing 20. As a result, the conductive wire can be routed in a wider range, and a more sufficient inductance can be obtained.

  In addition, it is arbitrary whether the wiring pattern which connects between the connecting terminal 92a and the connecting terminal 93a is formed on the mounting substrate 91 or the wiring layer in the mounting substrate 91. The same applies to the wiring pattern that connects the connection terminal 92b and the connection terminal 93b.

  The bent shape of the mounting substrate 91 can also be expressed as follows. The mounting substrate 91 is formed along the inner surface of the housing 20 from the corner facing the corner of the housing 20 provided with the beam 26 to the corner provided with the beam 26. Extend. Thereby, the mounting substrate 91 extends along the inner surfaces of the side wall 21c and the side wall 21b of the housing 20. This makes it possible / easy to ensure a sufficiently large inductance on the mounting substrate 91.

  Also in the present embodiment, as in the second embodiment, the coil mounting board 90 is attached to the side wall 21 of the housing 20 where the piezo element 50 is not disposed in the vicinity. By attaching the coil mounting substrate 90 to a place where there is a space in the housing 20, it is possible to effectively suppress the size of the housing 20 from increasing in the z-axis direction.

  FIG. 46 shows a coil mounting board 90 according to a modification. As shown in FIG. 46, connection terminals 93 may be arranged. In this case, the same effect as that of the present embodiment can be obtained. The arrangement position of the connection terminal 93 only needs to correspond to the arrangement position of the lead terminals 81 and 82. 46, when the connection terminal 93 is provided on the lower side of the mounting substrate, in order to prevent a short circuit between the connection terminal 92 and the connection terminal 93, the height of the body 81b of the lead terminal 81 (the body 81b). (Length in the y-axis direction) should be reduced. As is apparent from this modification, the positions where the connection terminals 92 and 93 are provided can be changed as appropriate.

[Fourth Embodiment]
The fourth embodiment will be described with reference to FIG. In the camera module 100 shown in FIG. 47, the lens holder 31 is displaced based on a driving method different from the driving method described in the above embodiment. Even in this case, the same effect as that of the above-described embodiment can be obtained.

  As shown in FIG. 47, the piezo element 50 is fixed in position relative to the housing 20. By placing the piezo element 50 on the transparent substrate 13, the piezo element 50 is fixed in position with respect to the housing 20. The transmission shaft 51 is fixed to the upper surface of the piezo element 50 via an adhesive 70. Further, the upper end portion of the transmission shaft 51 is fixed to the lid 60.

  The lens holder 31 is engaged with the transmission shaft 51 through the shaft holding portion 40 in a state in which the lens holder 31 can move up and down. The shaft holding portion 40 is engaged with the transmission shaft 51 in a state where the shaft holding portion 40 can slide on the transmission shaft 51. In response to the driving of the piezo element 50, the lens holder 31 moves on the transmission shaft 51 along the y-axis. The transparent substrate 13 is electrically connected to the wiring substrate 10 via the bumps BP.

  When a sawtooth drive voltage waveform is applied to the piezo element 50, the lens holder 31 behaves differently from the above-described embodiment. Specifically, the lens holder 31 is displaced when the driving voltage is slowly decreased, and the lens holder 31 is not displaced when the driving voltage is rapidly increased. Thus, even when the driving method of the lens holder 31 is different, the invention disclosed in the above-described embodiment can be applied. In the case of this embodiment, the same drive voltage generation circuit as that in the above embodiment can be used. According to the studies by the inventors, it has been confirmed that a slight gain can also be obtained in the present embodiment. In the present embodiment, a coil for preventing an inrush current when the driving operation is reversed may be required. Even in this case, the invention disclosed in the above embodiment can be applied.

  Note that only the piezo element 50 may be directly fixed to the housing 20. Only the transmission shaft 51 may be directly fixed to the housing 20. The piezo element 50 may be fixed to the housing 20 via an elastic member such as a sheet rubber. Similarly, the transmission shaft 51 may be fixed to the housing 20 via an elastic member.

  Note that the present invention is not limited to the above-described embodiment, and can be changed as appropriate without departing from the spirit of the present invention. The operation system of the drive device is arbitrary. The present invention is applied to a drive device in which the piezo element 50 or the transmission shaft 51 is fixed to a fixed side member, and the lens holder 31 slides on the transmission shaft 51 fixed to the fixed side member. Also good. In this method, the piezo element and the transmission shaft 51 are also fixed members.

  A specific mode for forming the coil by pattern wiring is arbitrary. The conductive pattern may be formed in a spiral shape.

100 camera module

10 Wiring board 12 Image sensor 13 Transparent board

20 housing

30 Lens unit 31 Lens holder 32 Connecting part 35 Rail receiving part 40 Shaft holding part

50 Piezo element 51 Transmission shaft 52 Lead wire

60 lids

81 Lead terminal 82 Lead terminal 85 Detaching part

90 Coil mounting substrate 91 Mounting substrate 92 Connection terminal 93 Connection terminal 95 Coil chip

Claims (19)

A driving device that displaces a moving object with respect to a stationary member based on driving of a piezoelectric element,
The moving object is attached to the fixed side member in a state where the moving object can be displaced according to driving of the piezoelectric element, and a pair of electrode terminals of the piezoelectric element are individually connected to the outside. A set of lead terminals are provided,
At least one of the set of wirings formed between the set of electrode terminals and the set of lead terminals includes a circuit element included in a circuit that supplies a drive voltage waveform to the piezoelectric element. Drive device.   The drive device according to claim 1, wherein the circuit element is a coil having a chip shape or a wiring pattern.   The drive device according to claim 2, further comprising a mounting substrate including the coil. The fixed side member includes an envelope that surrounds the moving object,
The envelope includes a set of the lead terminals,
The drive device according to claim 3, wherein the mounting board is disposed inside the envelope. The mounting board includes a set of connection terminals connected to the set of the lead terminals,
5. The driving device according to claim 4, wherein when the mounting board is disposed in the envelope, the set of the lead terminals and the set of the connection terminals are disposed to face each other. The envelope is a polygonal box-shaped member having a plurality of side walls,
The mounting board includes a first board part extending along a first side wall of the envelope and a second board part extending along a second side wall of the envelope,
The driving device according to claim 4, wherein the wiring pattern is formed on the first substrate portion and the second substrate portion.   The drive device according to any one of claims 1 to 6, further comprising a drive voltage generation circuit as the circuit for supplying a drive voltage waveform to the piezoelectric element. The drive voltage generation circuit includes:
A first drive circuit that applies a drive voltage from one side electrode of the piezoelectric element; and a second drive circuit that applies a drive voltage from the other side of the piezoelectric element, the first drive circuit and the second drive. An alternating drive voltage for expanding and contracting the piezoelectric element by switching a circuit;
Each of the first drive circuit and the second drive circuit includes an inductive element as the circuit element,
The frequency of the drive voltage waveform is a frequency range in which the gain is greater than zero dB due to the interaction of the switch resistance, the capacitance of the piezoelectric element, and the inductance of the inductive element included in the first and second drive circuits. The driving device according to claim 7, wherein the driving device is selected from the following.   The frequency of the drive voltage waveform is from a frequency range in which the gain is greater than 2 dB due to the interaction of the switch resistance, the capacitance of the piezoelectric element, and the inductance of the inductive element included in the first and second drive circuits. The drive device according to claim 8, wherein the drive device is selected.   The frequency of the drive voltage waveform is a frequency range in which the gain is greater than zero by the interaction of the switch resistance included in the first and second drive circuits, the capacitance of the piezoelectric element, and the inductance of the inductive element. The driving apparatus according to claim 9, wherein 10% before and after the frequency of the resonance point is selected from the excluded frequency range.   The frequency of the drive voltage waveform is a frequency range in which the gain is greater than zero by the interaction of the switch resistance included in the first and second drive circuits, the capacitance of the piezoelectric element, and the inductance of the inductive element. The driving device according to claim 10, wherein the driving device is selected from a frequency range smaller than the frequency of the resonance point. A piezoelectric element having a set of electrode terminals;
A drive shaft that receives vibration transmitted from the piezoelectric element in accordance with the driving of the piezoelectric element;
A moving object that is displaced according to the driving of the piezoelectric element;
A fixed-side member provided with a set of lead terminals to which the moving object is attached in a state in which the moving object is displaceable in accordance with driving of the piezoelectric element and which individually connects the set of electrode terminals to the outside. When,
A first circuit element included in a circuit for supplying a drive voltage waveform to the piezoelectric element and included in one of a set of wirings formed between the set of electrode terminals and the set of lead terminals When,
A drive device comprising:   Second included in the circuit for supplying a driving voltage waveform to the piezoelectric element and included in the other of the set of wirings formed between the set of electrode terminals and the set of lead terminals. The drive device according to claim 12, further comprising a circuit element.   14. The driving apparatus according to claim 13, wherein the first and second circuit elements are coils formed in a chip shape or a wiring pattern.   The driving device according to claim 14, further comprising a mounting substrate including the coil. The fixed side member includes an envelope that surrounds the moving object,
The envelope includes a set of the lead terminals,
The drive device according to claim 15, wherein the mounting board is disposed inside the envelope.   The driving apparatus according to claim 1, wherein the moving object includes a lens holding body including a lens. A drive device according to claim 17,
An image sensor that captures an image input via the lens;
An image acquisition apparatus comprising:   An electronic device comprising the image acquisition device according to claim 18.

Images