An actuator is provided with: the fixed part being formed by arranging either a coil part or a magnet part on a base member on the external peripheral side of the driven part; a movable part having a frame-like holding member for arranging and holding the other of the coil part or the magnet part on the base-member-side surface on the external peripheral side of the driven part; and a support part for inclinably supporting the movable part in relation to the fixed part, the support part being disposed on the base member. The holding member has, on the surface on the opposite side from the base member and farther inward than the arrangement area of either the coil part or the magnet part, a mounting surface part on which a first capturing module and a second capturing module are mounted as driven parts.

TECHNICAL FIELD

The present invention relates to a camera-shake correction actuator, a camera module having a camera-shake correcting function, and a camera-mounted device.

BACKGROUND ART

In general, a small-sized camera module is mounted in a mobile terminal such as a smartphone. Such a module often has an autofocus function for automatically focusing on a subject at the time of image capturing, and a camera-shake correcting function (optical image stabilization (OIS)) for reducing irregularities of an image by correcting camera shake (vibration) that occurs at the time of image capturing.

As a lens driving device having the autofocus function, for example, a lens driving device illustrated in PTL 1 is known.

The autofocusing lens driving device is provided with: an autofocusing coil disposed, for example, around a lens part; an autofocusing magnet disposed as radially separated from the AF coil; and an elastic support member (for example, a flat spring) that elastically supports an autofocus movable part including a lens part and the AF coil, on an autofocus fixing part including the AF magnet, for example. Hereinafter, the autofocusing coil is referred to as an “AF coil”, the autofocusing magnet is referred to as an “AF magnet”, the autofocus fixing part” is referred to as an “AF-fixing part”, and the autofocus movable part” is referred to as an “AF-movable part.” Automatic focusing is possible by moving the AF movable part in an optical-axis direction with respect to the AF fixing part by using a driving force of a voice coil motor made up of the AF coil and the AF magnet. Note that there are cases where the AF-fixing part includes the AF coil, and the AF-movable part includes the AF magnet.

Further, as the camera-shake correction method, a module tilt method of integrally tilting a capturing module is known (for example, PTL 2). The capturing module is a module having a lens part and a capturing device (for example, a charge coupled device (CCD)), and includes a module having an autofocusing actuator.

Hereinafter, the autofocusing actuator is referred to as an “AF actuator,” and the camera-shake correcting actuator is referred to as “OIS actuator.”

FIG. 1is an external view illustrating an example of a camera module of a conventional module tilt type.FIG. 2is an exploded perspective view illustrating the example of the camera module of the conventional module tilt type. As illustrated inFIGS. 1 and 2, camera module2of the conventional module tilt type is provided with fixing body21, movable body22, elastic support part23, capturing module24, and shake detection part25. Fixing body21, movable body22, and elastic support part23constitute an OIS actuator.

Fixing body21has base member211, coil part212, and OIS print wiring board213. Coil part212is disposed on base member211. OIS print wiring board213feeds power to coil part212, and outputs a detection signal of shake detection part25to a control part.

Movable body22has yoke221, magnet part222, top plate223, and module guide224. Yoke221and magnet part222are disposed in respective housing parts formed in top plate223. Module guide224is fixed to top plate223. Capturing module24is disposed and fixed in a space sandwiched between a pair of module guides224.

Elastic support part23has a biaxial gimbal mechanism, and movable body22(top plate223) is fixed to an outer gimbal. Elastic support part23is disposed in a floating state at an approximate center of base member211and fixed by stopper231. Elastic support part23supports movable body22in a swinging rotatable manner about an X-axis and a Y-axis orthogonal to an optical axis (Z-axis), that is, elastic support part23supports movable body22in a tiltable manner.

Shake detection part25is made up of a gyro sensor that detects an angular velocity of capturing module24, for example. Shake detection part25is fixed to the side surface of module guide224of movable body22. The detection signal of shake detection part25is output to the control part through OIS print wiring board213that is fixing body21.

An OIS voice coil motor (VCM) is made up of coil part212and magnet part222. That is, when a current flows through coil part212, a Lorentz force is generated at coil part212due to interaction between the magnetic field of magnet part222and a current flowing through coil part212(Fleming's left hand rule). Since coil part212is fixed, a reactive force acts on magnet part222. This reactive force is the driving force of the OIS voice coil motor. Movable body22swings and rotates until the driving force of the OIS voice coil motor and a restoration force (returning force) of elastic support part23become equivalent to each other. As a result, displacement of the optical axis due to camera shake is corrected, and the optical-axis direction is kept constant.

CITATION LIST

Patent Literature

SUMMARY OF INVENTION

Technical Problem

In recent years, a camera module having a plurality of (typically, two) lens driving devices, a so-called dual camera, is being put to practical use. The dual camera has various possibilities according to its use, such as being able to simultaneously capture two images with different focal distances, and being able to simultaneously capture a still image and a moving image.

When the dual camera is formed using a plurality of camera modules of the module tilt type as in PTL 1, for each camera module having a plurality of AF functions, a driving device having an OIS actuator corresponding to each camera module is required.

Therefore, in the case of applying the dual camera to a mobile terminal such as smartphone by using the conventional lens driving device, the OIS actuators respectively corresponding to the plurality of camera modules inhibit size reduction and make it difficult to ensure the space for mounting the dual camera itself, and this is disadvantageous in productization.

An object of the present invention is to provide an actuator, a camera module, and a camera-mounted device that can be reduced in size and cost and are preferable for use of a dual camera free of camera shake.

Solution to Problem

An actuator according to the present invention is an actuator that tilts a driven part for shake correction by using a driving force of a voice coil motor including a coil part and a magnet part, the actuator including:

a fixing body that includes a base member and is provided with one of the coil part or the magnet part on the base member on an outer peripheral side of the driven part;

a movable body that includes a frame-shaped holding member that is provided with and holds the other of the coil part or the magnet part on a surface on a side of the base member on an outer peripheral side of the driven part; and

a support part that is disposed on the base member and tiltably supports the movable body with respect to the fixing body, in which

the driven part is a first capturing module and a second capturing module each including a lens part and a capturing device, and

the holding member includes a mounting surface part on which the first capturing module and the second capturing module are mounted on a surface on a side opposite from the base member and more inside than a provided location of one of the coil part or the magnet part.

A camera module according to the present invention includes:

the actuator mentioned above;

a first capturing module and a second capturing module bonded to the holding member as the driven part, the first capturing module and the second capturing module each including a lens part and a capturing device; and

a shake detection part that detects shake of the capturing module.

A camera-mounted device according to the present invention is an information device or a transporting device, the device including the camera module mentioned above.

Advantageous Effects of Invention

According to the present invention, it is possible to achieve a dual camera that can be reduced in size and cost and has no error of camera-shake correction.

DESCRIPTION OF EMBODIMENT

FIGS. 3A and 3Billustrate smartphone M (camera-mounted device) mounted with camera module100, to which a lens driving device as an actuator according to one embodiment of the present invention has been applied.FIG. 3Ais a front view of smartphone M andFIG. 3Bis a rear view of smartphone M.

The smartphone M has a dual camera made up of two rear cameras OC1, OC2. Camera module100is applied as a device provided with both rear cameras OC1, OC2of the dual camera.

Camera module100is provided with an autofocus function concerning each of cameras OC1, OC2, and can optically correct camera shake (vibration) that occurs at the time of image capturing to capture an image without blurring, while automatically focusing on a subject at the time of image capturing. For the camera-shake correcting function of camera module100, a module tilt method is employed. The module tilt method has an advantage in that no distortion is generated at four corners of the screen.

FIG. 4is an external perspective view of camera module100.FIG. 5is an external perspective view illustrating lens driving device1with a cover portion removed therefrom in camera module100, andFIG. 6is an exploded perspective view of camera module100.FIG. 7is a sectional view along an X-direction of camera module100.FIG. 8is a sectional view along a Y-direction of camera module100. Note thatFIGS. 7 and 8especially illustrate a magnetic circuit part of a voice coil motor portion.

Here, a description will be given using an orthogonal coordinate system (X, Y, Z) as illustrated inFIGS. 4 and 8. Camera module100is mounted such that, when an image is actually captured with smartphone M, the X-direction is a vertical direction (or horizontal direction), the Y-direction is a horizontal direction (or vertical direction), and Z-direction (including an optical-axis direction) is a front-rear direction.

As illustrated inFIGS. 4 to 8, camera module100is provided with fixing body11, movable body12, elastic support part13, a plurality of capturing modules14(14a,14b), shake detection part15, driver IC60, and the like. Note that camera module100may be provided with positional displacement detection part16b. Fixing body11, movable body12, and elastic support part13constitute lens driving device1having a function as an OIS actuator. In lens driving device1, camera-shake correction is performed using driving force of an OIS voice coil motor having coil part112and magnet part122. While camera module100may be provided with two or more capturing modules as the plurality of capturing modules14, camera module100is assumed here to be a camera module provided with two capturing modules that are first capturing module14aand second capturing module14b.

Fixing body11is fixed so as not to be movable when installed in smartphone M. Fixing body11movably supports movable body12via elastic support part13. Fixing body11has base plate111constituting the base member together with coil part112, coil substrate113, skirt member (cover member)114, module cover member (hereinafter referred to as “upper cover member”, seeFIGS. 4 and 5)115, flexible cover member116(seeFIGS. 4 and 5), and printed circuit board117.

Base plate111is a substantially rectangular member made of a metal material. By making base plate111of metal, base plate111has high strength as compared to the case of making the base plate of resin, and can be reduced in thickness, and furthermore, the profile of camera module100can be reduced in height.

Base plate111has projection111ain a truncated pyramid shape for fixing elastic support part13to a central part of a region over which movable body12is disposed. Here, a central portion of projection111ais preferable disposed so as to pass through the Z-axis. Base plate111has, around projection111a, a pat-like power feeding part111bfor feeding power to coil part112.

On base plate111, coil substrate113is disposed in a region over which movable body12is disposed. Projection111aprojects upward from a center opening of coil substrate113. Base plate111may be provided with a projection side part that protrudes from the peripheral edge of coil substrate113and is engaged with a notch of skirt member114, to which upper cover member115is fixed, to perform positioning at the time of fixing upper cover member115and skirt member114. In addition, printed circuit board117is disposed on a part of base plate111.

As illustrated inFIG. 6, on base plate111of fixing body11, a piece part having a recessed (U-shaped) notch may be vertically provided in a central portion of the two orthogonal sides out of four sides constituting the peripheral edge, and hole element16bas a positional displacement detection part may be provided in the recessed shape. Note that hole element16bis virtually illustrated inFIG. 6and omitted in the other drawings.

When positional displacement detection part16bis provided, positional displacement detection part16bcan sense movement (rotation and swinging) of movable body12, namely the plurality of capturing modules14a,14b, and can detect in a non-contact manner the position of movable body12, namely the plurality of capturing modules14a,14b, in the plane direction (XY-directions) orthogonal to the optical axis. In other words, positional displacement detection part16bcan sense rotation and swinging of movable body12, namely postures of the plurality of capturing modules14a,14b, to detect tilting thereof with respect to the X-axis and the Y-axis. When positional displacement detection part16bis provided, positional displacement detection part16bis installed on coil substrate113and connected to connection terminal part113dvia a wiring pattern of coil substrate113.

Coil substrate113is a substrate having a circuit connected to each of input and output terminals of an electronic component used in lens driving device1for realizing OIS.

Coil substrate113is a flexible printed wiring board formed in a rectangular shape with wiring connected to coil part112(and positional displacement detection part16b). Note that the wiring of coil substrate113is a wiring pattern including a power source line of coil part112, and when positional displacement detection part16bis provided, the wiring also includes a signal line of positional displacement detection part16b. Here, coil substrate113has tilt coils112A to112D as coil part112, two hole elements as positional displacement detection part16b, and connection terminal part113dmade up of the total of twelve pins, connected to the hole elements. That is, the wiring pattern of coil substrate113includes wiring that connects tilt coils112A to112D, hole element16b, and connection terminal part113d. Connection terminal part113dis formed in a part extending laterally from a part of the outer periphery of a rectangular portion. For example, the connection terminal part113dhas twelve pin terminals, and the twelve pin terminals consist of the total of four pins, two pins each of the input and output terminals for each of the facing tilt coils112A to112D, and the total of eight pins of the hole elements16b.

Coil substrate113is disposed on printed circuit board117that is fixed while placed on part111dof base plate111, and connection terminal part113dis connected to connection terminal part117bon printed circuit board117.

On coil substrate113, along with power feeding to coil part112, a signal of positional displacement detection part16bcan be output and input to a connecting destination via connection terminal part113d. Here, when positional displacement detection part16bis provided, its detection signal is output to a circuit of printed circuit board117since connection terminal part113dis connected to connection terminal part117bof printed circuit board117. Note that the detection signal of positional displacement detection part16bis output to the control part (not illustrated) via the circuit of printed circuit board117.

Coil part112constitutes a voice coil motor together with magnet part122described later, and tilts first capturing module14aand second capturing module14bboth at once for shake correction by the driving force of the voice coil motor.

Coil part112is provided on the outer peripheral sides of first capturing module14aand second capturing module14b. Coil part112is made up of four tilt coils112A to112D and disposed on coil substrate113on base plate111so as to surround projection111a. Coil part112(tilt coils112A to112D) is provided with a winding shaft of the coil oriented in a direction in which base plate111and yoke (holding member)121face each other. Power is fed to coil part112(tilt coils112A to112D) via a power feeding part of coil substrate113.

Tilt coils112A,112C face each other in the X-direction are used in the case of rotating and swinging movable body12about Y-axis. Tilt coils112B,112D face each other in the Y-direction and is used in the case of rotating and swinging movable body12about X-axis.

Skirt member114is a member formed by connecting four wall bodies114bin a rectangular frame shape, and has reception port114aof capturing modules14a,14bon the upper surface. Rectangular regulation part114din a rectangular frame shape is provided in the upper part of each wall body114bof skirt member114, regulation part114dslightly protruding inward from each upper part and forming an opening edge of reception port114a. Regulation part114dprevents excessive tilting of movable body12(specifically, yoke121and magnet part122) disposed in skirt member114via the inside of the frame shape, namely reception port114aof skirt member114.

Skirt member114is fixed by being externally engaged with the outer peripheral edge of base plate111after movable body12is attached to base plate111, on which coil substrate113is superimposed, via elastic support part13. Movable body12is movably laid across base plate111and skirt member114.

Upper cover member115is a member in a covered rectangular cylindrical shape having a plurality of openings115aon a lid portion on the upper surface. Upper cover member115causes the respective lens parts of first capturing module14aand second capturing module14b(illustrated as body141of the module) to face the outside via a plurality of openings115a.

After the plurality of capturing modules14a,14bare mounted on lens driving device1, upper cover member115is externally engaged with skirt member114and fixed to base plate111. One side surface of upper cover member115is provided with outlet115bfor extracting, to the outside, capturing-module printed wiring board143drawn from body141of capturing modules14a,14b. Outlet115bis covered with flexible cover member116. Flexible cover member116covers a portion over the upper surface of skirt member114on capturing-module printed wiring board143in a state where a movable region of movable body12is ensured.

Movable body12swings and rotates (rotates at an angles of Xθ and Yθ) about the X-axis and Y-axis with respect to fixing body11. Movable body12has yoke (holding member)121, magnet part122, and a pair of module guides123a,123b. At the time of installing capturing modules14a,14bon lens driving device1, yoke121is held by directly arranging capturing modules14a,14b. Capturing modules14a,14bare, for example, bonded to the upper surface of yoke121with, for example, a double-sided tape, a resin-made adhesive bond, or the like. Here, capturing modules14a,14bare fixed by being uniformly disposed on a stepped surface part (mounting surface part)121bconstituting the opening edge of the central portion of yoke121. Yoke121is formed in a recessed shape that is opened upward, and the plurality of capturing modules14a,14bas the driven part are disposed in the recessed shape. Therefore, without use of the positioning member like the module guide described in PLT 2, it is possible to highly accurately position and fix capturing modules14a,14bto yoke121, with the recessed inner wall serving as a guide.

Yoke121is a member in a rectangular frame shape formed of a magnetic material, and has rectangular yoke body (holding part body)121a, a stepped surface part121bin a flat frame shape that is provided on the inside of the frame shape of yoke body121aand fixes capturing module14placed, and second stepped surface part (gimbal fixing part)121cat the lowest level.

Yoke body121ais formed in a flat frame shape obtained by connecting four flat panels into a rectangular shape, with magnet part122fixed to the bottom surface. Yoke121has an outer hanging part121dformed so as to project downward and hang along the outer peripheral edge of yoke body121aconstituting an upper panel portion of yoke121(specifically, the outer edge of each flat panel constituting yoke body121a). Further, in the inner peripheral edge of yoke body121a(specifically, the inner edge of each flat panel constituting yoke body121a), an inner hanging part is formed facing outer hanging part121din the direction orthogonal to the Z-direction, along the inner peripheral edge.

In yoke121, the inner hanging part forms a step, and with this inner hanging part, a stepped surface part (mounting surface part)121bis formed downward in a stepped shape on the inner peripheral side of yoke body121a. Further, a second stepped surface part (gimbal fixing part)121cis continuously provided at the inner peripheral edge of stepped surface part121b, second stepped surface part121cconstituting the bottom surface of the central part of yoke121at a position lower than stepped surface part121b.

As thus described, the cross-sectional shape of one side of yoke121is a recessed shape opened to the base plate111side, and is a “U” shape opened downward at the center. Yoke body121abeing the bottom surface in this recessed shape and a provided location of magnet part122is located at a position separated from base plate111more than stepped surface part121band second stepped surface part121c. Specifically, stepped surface part121bis formed in a flat rectangular frame shape and joined, at its outer peripheral edge, to the inside of yoke body121aat a position lower than yoke body121a. Additionally, second stepped surface part121cis formed in a flat rectangular frame shape and joined, at its outer peripheral edge, to the inside of stepped surface part121bat a position lower than stepped surface part121b.

The plurality of capturing modules14a,14bare fixed in a disposed state to the central portion recessed in yoke121, namely, onto stepped surface part (mounting surface part)121bof the rectangular flat shape inside yoke body121a.

The respective bottom surface of first capturing module14aand second capturing module14bthat are the plurality of capturing modules14are fixed to the upper surface of stepped surface part121b(a part of the upper surface of yoke121) with a double-sided tape or a resin-made adhesive bond. In the present embodiment, capturing modules14a,14bare fixed onto the stepped surface part143bof yoke121, but capturing modules14a,14bmay be attached in any manner as long as the bottom surfaces thereof are located at lower positions of the height level than yoke body121a. Capturing modules14a,14bmay be configured to be fixed onto second stepped surface part121c.

A pair of module guides123a,123bare vertically provided upward from yoke121. On the plurality of capturing modules14a,14bfixed onto stepped surface part121bof yoke121, module guides123a,123bface each other so as to sandwich capturing modules14a,14bfrom the right and left in the Y-direction. Thereby, module guides123a,123bserve as guides at the time of placing and fixing capturing modules14a,14bonto stepped surface part121bof yoke121. Then, the pair of module guides123a,123bare also fixed via an adhesive bond or the like to one side surfaces (the side surface separated in the Y-direction) of capturing modules14a,14b, that module guides123a,123bface respectively. Hence capturing modules14a,14bare correctly attached to movable body12, so that improvement in reliability can be realized. Note that module guides123a,123bare projected upward from reception port114aof skirt member114along with first capturing module14aand second capturing module14b.

As thus described, in yoke121, first capturing module14aand second capturing module14bare fixed in stepped surface part121blocated lower than yoke body121a, to which magnet part122is fixed. That is, magnet part122is located at a position closer to outer peripheral side than stepped surface part121band higher than stepped surface part121b. That is, yoke body121ais disposed at a position around stepped surface part121band second stepped surface part121cand separated from base plate111in the Z-direction more than stepped surface part121b.

Magnet part122is made up of four permanent magnets122A to122D in a rectangular parallelepiped shape, respectively corresponding to tilt coils112A to112D. An electromagnet may be used instead of the permanent magnet. Each of permanent magnets122A to122D has such a size with which permanent magnets122A to122D are accommodated inside tilt coils112A to112D.

Permanent magnets122A to122D are disposed on the lower surface of the respective flat plates of yoke121such that a magnetization direction is parallel to the Z-direction, and is fixed by bonding, for example.

Further, permanent magnets122A to122D are located between outer hanging part121dof yoke121and the inner hanging part facing outer hanging part121d. Here, permanent magnets122A to122D face to each of the inner hanging part and outer hanging part121dat a position where a gap is provided from each of the hanging parts in yoke body121aformed in inverted U shapes between inner hanging part and outer hanging part121d.

Coil part112is located between magnet part122and yoke121(specifically, yoke body121a) (seeFIGS. 7, 8). Magnet part122is located on the winding axis of the winding of coil part112. Magnet part122and coil part112are disposed such that in yoke121and base plate111, the central part of coil part112is opened along the bonding direction of capturing module14, and magnet part122projects in the central part of coil part112.

Specifically, tilt coils112A to112D are located between outer hanging part121dand permanent magnets122A to122D and between the inner hanging part and permanent magnets122A to122D. With the periphery of coil part112being covered by yoke121, it is possible to avoid the AF actuator of body141of each of capturing modules14a,14bfrom being adversely affected due to a magnetic field generated by a flowing current of coil part112.

Further, magnet part122and coil part112, namely the magnetic circuit part having these parts, are located at lower ends of capturing modules14a,14band on the outer peripheral side of stepped surface part121b(specifically, XY-direction sides). That is, the magnetic circuit part having magnet part122and coil part112is not disposed immediately under the lower end of capturing module14or stepped surface part121b. In other words, magnet part122(permanent magnets122A to122D) and coil part112(tilt coils112A to112D) are disposed on coil substrate113that overlaps base plate111at the lower ends of capturing modules14a,14bdisposed in the Y-direction and on the outer peripheral side in the XY-directions of stepped surface part121bof yoke121.

Elastic support part13is made of a rectangular member (so-called gimbal spring) having a biaxial gimbal mechanism.FIG. 9is a bottom view of movable body12illustrating a yoke121, to which elastic support part13has been attached.

As illustrated inFIG. 9, elastic support part13has a central part13a, frame-shaped gimbal part13bdisposed so as to surround central part13aat the center, Y-axis connection part13c, and X-axis connection part13d. Elastic support part13is disposed in the opening inside yoke121, and here, elastic support part13is connected at the opening edge of the lower surface of yoke121. Specifically, elastic support part13is disposed so as to be parallel to the lower surface of second stepped surface part121cat the lowest position in yoke121. Central part13ais disposed at the center of the opening of yoke121. Central part13aand gimbal part13bare connected by X-axis connection part13dextending in the X-direction, and gimbal part13band the lower surface of yoke121are connected by Y-axis connection part13cextending in the Y-direction.

Thereby, yoke121and central part13acan be relatively revolve and swing about Y-axis connection part13cdue to deformation of elastic support part13including Y-axis connection part13c, and can revolve and swing about X-axis connection part13ddue to deformation of elastic support part13including X-axis connection part13d. InFIG. 9, the gimbal being elastic support part13is indicated by hatching so as to be differentiated from the other constituent members.

As illustrated inFIG. 9, here, central part13ais formed in a rectangular frame shape, and central part13acan swing and rotate with respect to yoke121about the X-axis and the Y-axis via frame-shaped gimbal part13bsurrounding central part13a. Note that elastic support part13may be configured such that gimbal part13band central part13aare connected by Y-axis connection part13cextending in the Y-axis direction, and gimbal part13band yoke121are connected by X-axis connection part13dextending in the X-axis direction.

Central part13aof elastic support part13is bonded or welded onto projection111aof base plate111. Thus, in elastic support part13, as illustrated inFIGS. 7 and 8, a portion closer to the outer peripheral side than central part13acomes into the state of being located at a predetermined interval from the upper surface of base plate111. This predetermined interval is a movable range of elastic support part13during revolution about the central shafts in the X-direction and the Y-direction in which elastic support part13is movable. Note that first capturing module14aand second capturing module14bthat are the plurality of capturing modules are preferably disposed in proximity from the center of central part13aat an equal interval.

Further, as illustrated inFIG. 9, in elastic support part13, gimbal part13bis connected to central part13avia X-axis connection part13d, and gimbal part13bis bonded or welded to a pair of parallel side parts of the lower surface of stepped surface part121bor second stepped surface part121cof yoke121via Y-axis connection part13cextending in the Y-axis direction. As a result, movable body12is disposed in the state of being raised at the substantially center of base plate111(specifically, coil substrate113), orthogonal to the optical axis, and become able to swing and rotate about two mutually orthogonal directions, namely the X-axis and the Y-axis.

With elastic support part13being fixed to base plate111by bonding, a fitting member such as the stopper described in PLT 1 is not required.

Further, in the present embodiment, elastic support part13is attached, via Y-axis connection part13c, to the lower surface of second stepped surface part121clocated on the lower side than stepped surface part121bbonded to the upper surfaces of first capturing module14aand second capturing module14b. Therefore, the length of separation between elastic support part13and capturing module14in the Z-direction almost corresponds to the thickness of second stepped surface part121cin addition to the thickness of stepped surface part121b. Therefore, in skirt member114, it is possible to ensure the rotation swinging region of yoke121, and to reduce the length of camera module100itself in the Z-direction, namely to lower the profile of camera module100.

Capturing module14is first capturing module14aand second capturing module14b. Each of first capturing module14aand second capturing module14bhas body141including the lens part, the capturing device, and the AF actuator, and capturing-module printed wiring board143connected to body141.

The capturing device (not illustrated) is made up of, for example, a charge coupled device (CCD) image sensor, a complementary metal oxide semiconductor (CMOS) image sensor, and the like. The capturing device (not illustrated) is installed on capturing-module printed wiring board143. The capturing device (not illustrated) captures a subject image, formed by the lens part. The AF actuator has, for example, an AF voice coil motor, and moves the lens part in the optical-axis direction by using the driving force of the AF voice coil motor. A known technique is applied to the AF actuator.

Capturing-module printed wiring board143is made up of flexible printed circuits having flexibility. Capturing-module printed wiring board143has a power source line (not illustrated) for feeding power to the coil part (not illustrated) of AF actuator2, a signal line (not illustrated) for a video signal output from the capturing device, and a signal line (not illustrated) for a detection signal output from shake detection part15. When capturing-module printed wiring board143along with capturing module14is mounted on lens driving device1, as illustrated inFIGS. 4, 5, and 6, a drawing part143aof capturing-module printed wiring board143gets over skirt member114from the inside of skirt member114and is pulled out to the outside via outlet115bof upper cover member115. Specifically, drawing part143aof capturing-module printed wiring board143extends upward from the lower surfaces of capturing modules14a,14b, is bent above skirt member114with a predetermined interval therefrom so as to extend toward the outside of the skirt part, and is extended from outlet115bof upper cover member115to the outside. Capturing-module printed wiring board143having pulled out is connected to connector117aof printed circuit board117of fixing body11in end-side portion143b. As thus described, capturing-module printed wiring board143is configured to be provided in movable body12, but since having flexibility, the capturing-module printed wiring board143does not hinder the movability of movable body12. Note that capturing-module printed wiring board143may be branched in the middle, and different connectors may be mounted on a signal line for the video signal and a signal line for the detection signal.

Shake detection part15detects shake (movement) of electronic equipment such as a smartphone mounted with camera module100. Shake detection part15is made up of a gyro sensor that detects an angular velocity of camera module100(electronic equipment such as a smartphone mounted with camera module100). Shake detection part15detects shake in at least two orthogonal axes (X, Y) with respect to at least optical axis O (parallel to the Z-axis). Here, shake in each of three axial directions, the X, Y, and Z-directions, can be detected.

In the present embodiment, shake detection part15detects shake (movement) of the electronic equipment such as a smartphone mounted with camera module100to detect shake angles of movable body12, first capturing module14a, and second capturing module14b. Based on the detected shake angles, the flowing current of coil part112is controlled via driver IC60and movable body12is made movable to correct shake.

The detection signal of shake detection part15is output to the control part (not illustrated) via the circuit of printed circuit board117.

When positional displacement detection part16is provided, the control part (not illustrated) may control the flowing current of coil part112via driver IC60based on the above detection signal and a detection signal of positional displacement detection part16(for example, a hole element that detects positional displacement in each of the X-axis and the Y-axis). Note that the function of the control part (not illustrated) may be carried out by driver IC60. Further, a control part installed in smartphone M may be used via printed circuit board117. By detecting the tilting of camera module100itself by shake detection part15, a shake angle is detected, and when positional displacement detection part16bis provided, a detection signal (hole output value) corresponding to the detected angle is detected by positional displacement detection part16b, and based on the detected value, the flowing current of coil part112is controlled via driver IC60and movable body12is made movable to correct shake.

Driver IC60functions as the driving part that feeds power to coil part112to make movable body12movable by control of the control part (not illustrated), namely, drives first capturing module14aand second capturing module14bthat are attached to movable body12. In the present embodiment, shake detection part (gyro sensor)15is not provided on the side surface of first capturing module14aor second capturing module14b, but installed on printed circuit board117of camera module100. Shake detection part (gyro sensor)15detects a camera-shake angle, namely an angle of camera module100itself, as an angle of movable body12and, furthermore, angles of first capturing module14aand second capturing module14b, and outputs the detected angles to the control part. When positional displacement detection part16bis provided, in the control part, the flowing current of coil part112is controlled via driver IC60so as to obtain an output (hole output value) from a hole element that is positional displacement detection part16b, the output corresponding to the detected angle, and movable body12is made movable (tilted) to correct shake.

In lens driving device1, coil part112and magnet part122that constitute the magnetic circuit part of the OIS voice coil motor are disposed in positions to surround the plurality of capturing modules (first capturing module14aand second capturing module14b) that are objects to be moved. Specifically, the magnetic circuit part having magnet part122(permanent magnets122A to122D) and coil part112(tilt coils112A to112D) are disposed on base plate111on the outer peripheral side in the XY-directions with respect to the lower end of capturing module14and stepped surface part121bof yoke121. Further, magnet parts122are disposed bisymmetrically with respect to the center of gravity of movable body12mounted in yoke121, here, the same position as the center of the Z-axis.

The magnetic circuit part is disposed in a position where a part of the magnetic circuit part overlaps the lower end of capturing module14and stepped surface part121bof yoke121in the XY-directions. That is, one of magnet part122and coil part112(here, magnet part122) is disposed in a position where the disposed part overlaps in the XY-directions.

In the magnetic circuit part, permanent magnets122A to122D constituting magnet part122are disposed above tilt coils112A to112D constituting coil part112and in the state of being partially inserted inside tilt coils112A to112D. As a result, permanent magnets122A to122D are disposed above tilt coils112A to112D respectively corresponding thereto, along the winding directions (Z-direction) of respective tilt coils112A to112D. Further, each of magnet part122and coil part112is disposed in a position where a part of the magnetic circuit part overlaps peripheral side in the lower end of capturing module14and stepped surface part121bof yoke121on the outer peripheral side in the XY-directions.

In the OIS voice coil motor having magnet part122and coil part112disposed as thus described, in an initial state where a current is not flowing through coil part112, the capturing module14(movable body12) is held in a neutral position where the optical axis coincides with the Z-direction. Here, when capturing module14(movable body12) is offset from the neutral position due to gravity sagging or the like at the time of attaching movable body12to fixing body11, the offset position detected by positional displacement detection part16is corrected to be set in the neutral position where the optical axis coincides with the Z-direction.

That is, when a current flows through coil part112, a Lorentz force is generated at coil part112due to interaction between the magnetic field of magnet part122and the current flowing through coil part112(Fleming's left hand rule). Since coil part112is fixed, a reactive force acts on magnet part122that is movable body12. This reactive force is the driving force of the OIS voice coil motor.

Specifically, when mutually reversed currents are allowed to flow through tilt coils112A,112C facing each other in the X-axis direction, mutually reversed forces act on permanent magnets122A,122C in the Z-direction. Hence movable body12including capturing module14swings and rotates about the Y-axis with central part13aof elastic support part13taken as a supporting point. Similarly, when mutually reversed currents are allowed to flow through tilt coils112B,112D facing each other in the Y-axis direction, movable body12including capturing module14swings and rotates about the X-axis with central part13aof elastic support part13taken as a supporting point. Movable body12swings and rotates until the driving force of the OIS voice coil motor (a force that acts on magnet part122) and a restoration force of elastic support part13become equivalent to each other.

At this time, the flowing current of coil part112is controlled based on the detection result of shake detection part15such that the shake of capturing module14is offset by the swinging and rotation of movable body12. As a result, shift of the optical axis due to camera shake is corrected, and the optical-axis direction is kept constant.

Since the swinging rotation of movable body12is regulated by regulation part114dof skirt member114, it is possible to prevent movable body12from excessively swinging and rotating due to a falling impact or the like.

The bottom surface of capturing module14is fixed to the upper surface of stepped surface part121bof movable body12(a part of the upper surface of yoke121) with a double-sided tape or a resin-made adhesive bond. On the outer peripheral side of stepped surface part121b, yoke body121aof yoke121is connected to a position separated from base plate111in the Z-direction more than stepped surface part121b, namely a position higher than stepped surface part121b, via the inner hanging part of yoke121. Magnet part122is fixed to the lower surface of yoke body121a, and coil part112is disposed so as to be separated from magnet part122in the Z-direction with magnet part122being within coil part112. As thus described, the magnetic circuit part having magnet part122and coil part112is disposed on the outer peripheral side (outer side in the XY-directions) of stepped surface part121b, namely, the outer peripheral side of capturing module14. Here, magnet part122and coil part112are located outside the movable region of capturing module14.

In yoke121, magnet part122is fixed on the lower surface of yoke body121adisposed at a higher position of the height level than stepped surface part121b. That is, magnet part122is located at a position closer to outer peripheral side than stepped surface part121b, to which capturing module14is fixed, and higher than stepped surface part121b.

As thus described, the magnetic circuit part having magnet part122(permanent magnets122A to122D) and coil part112(tilt coils112A to112D) are disposed on base plate111at the lower end of capturing module14or on the outer peripheral side in the XY-directions of stepped surface part121bof yoke121. In other words, the magnetic circuit part is not disposed between base plate111and capturing module14where the height (Z-direction) is limited.

Further, in movable body12, yoke121has a recessed part formed of yoke body121a(specifically the inner hanging part), stepped surface part121b, and second stepped surface part121cin the central portion, and capturing module14is fixed into the recessed part.

By the driving force of the voice coil motor having magnet part122and coil part112as thus disposed, lens driving device1tilts a plurality of (first and second) capturing modules14a,14bthat are the driven part to correct shake.

Further, according to the present embodiment, lens driving device1has fixing body11, movable body12, and the support part (elastic support part13). Fixing body11has base plate111and is provided with either coil part112or magnet part122on the base member (base plate111, coil substrate113) on the outer peripheral side of the driven part (14a,14b). Movable body12has a frame-shaped holding member (yoke121) that is provided with and holds the other of coil part112and magnet part122on a surface on the side of the base member on the outer peripheral side of the driven part (14a,14b). The support part (elastic support part13) is disposed on the base member and tiltably supports movable body12with respect to fixing body11. The driven part (14a,14b) are first capturing module14aand second capturing module14beach having the lens part and the capturing device. The holding member (yoke121) has mounting surface part121b, on which first capturing module14aand second capturing module14bare arranged and mounted on the opposite-side surface from the base member and farther inward than the provided location of either coil part112or magnet part122. Yoke (holding member)121has a step that makes placed locations (mounting surface part121b) of the plurality of capturing modules14a,14bcloser to the base member than the provided location (yoke body121a) of either coil part112or magnet part122.

According to this lens driving device1, the plurality of capturing modules (here, first capturing module14aand second capturing module14beach having the AF function) can be mounted on yoke121both at once and driven by one OIS actuator. As a result, also as the dual camera mounted with first capturing module14aand second capturing module14b, camera-shake correction can be performed by one OIS actuator, thereby eliminating the need for using the OIS actuator corresponding to each of first capturing module14aand second capturing module14b. It is thus possible to make the dual camera itself compact.

Lens driving device1has frame-shaped skirt member114that is fixed to base plate111and the peripheral edge of base plate111. Movable body12is laid across base plate111and skirt member114. According to lens driving device1, the number of parts further decreases as compared to the conventional configuration, thereby facilitating the assembly process while enabling further reduction in profile. Just by bonding capturing module14with the autofocus function to yoke121, camera module100can be completed in a simple manner.

In the case of performing OIS camera-shake correction, lens driving device1performs the correction by adjusting the posture of yoke121itself, namely an angle. Therefore, when lens driving device1performs camera-shake correction, it is possible to simultaneously correct the angles of the plurality of capturing modules14a,14b. That is, even when focal distances of the plurality of capturing modules14a,14bare different from each other, the capturing modules14a,14bcan be corrected with the same correction quantity in the compact configuration. As thus described, even when capturing modules14a,14bare provided with the AF function, it is possible to achieve a compact lens driving device capable of performing favorable camera-shake correction without a camera-shake correction error between capturing modules14a,14b.

According to lens driving device1, the placed locations of the plurality of capturing modules14a,14bin yoke121can be made lower than the provided locations of coil part112and magnet part122, to more reliably realize further reduction in profile. At the same time, the height of magnetic circuit part, namely the length of coil part112or magnet part122is not limited, thereby not causing a deterioration in magnetic efficiency or an increase in power consumption accompanied by the deterioration. That is, it is possible to ensure a height space required to constitute the magnetic circuit part by using the outer peripheral space of the plurality of capturing modules14a,14b, whereby the configuration of the magnetic circuit part itself can be increased in height direction. For example, the height (Z-direction) of coil part112(tilt coils112A to112D) can be made larger by increasing the number of windings thereof, or the length of magnet part122(permanent magnets122A to122D) in the Z-direction can be made larger. This can further increase a magnetic force, thereby increasing the magnetic efficiency and lower the power consumption.

Coil part112(tilt coils112A to112D) is provided with a winding shaft of the coil of coil part112(tilt coils112A to112D) oriented in the direction in which base plate111and holding member (yoke)121face each other. Magnet part122(permanent magnets122A to122D) is provided so as to project in the central part of coil part112(tilt coils112A to112D). Hence coil part112and magnet part122can be increased in the height direction (Z-direction) without being increased in the outer peripheral side (XY-directions). As a result, the configuration of the magnetic circuit part itself can be increased without increasing the space for disposing the magnetic circuit part itself in lens driving device1.

When the hole element is provided as positional displacement detection part16b, a leakage flux between magnet part122and coil part112is detected, so that the moving quantities of capturing module14in the X-axis direction and the Y-axis direction can be directly detected via tilting of yoke121. It is thereby possible to detect an offset due to an empty weight (gravity sagging) of the plurality of capturing modules14a,14bduring non-driving time, or it is possible to detect an offset due to a reactive force of flexible printed circuits (FPCs) in the plurality of capturing modules14a,14bat the time when movable body12is fixed to fixing body11. Accordingly, the offset positions of the plurality of capturing modules14a,14bare detected and corrected by using positional displacement detection part16, whereby camera module100can position the plurality of capturing modules14a,14bwithout tilting at the time of activation. In other words, when the control part (not illustrated) is provided with positional displacement detection part16bat the time of correcting the shake (angle shake) of camera module100itself, the shake corresponding to the detection signal of shake detection part15, the control part can perform control (so-called feedback control) on the flowing current of coil part112based on the detection signal such that movable body12and capturing module14return to reference positions.

In the present embodiment, elastic support part (support part)13tiltably supports movable body12with respect to fixing body11by elastic deformation. Frame-shaped holding member (yoke)121has stepped surface part (mounting surface part)121bon which capturing modules14a,14bare mounted, and second stepped surface part (gimbal fixing part)121c, to which elastic support part13is attached on the stepped surface part lower than stepped surface part121b, second stepped surface part being disposed inside stepped surface part121b.

Specifically, second stepped surface part121cof yoke121is formed one level lower than stepped surface part121b, and a separation distance between each of capturing modules14a,14band elastic support part13is larger by the step formed one level lower. That is, the bottom surfaces of capturing modules14a,14bare located in positions separated in advance from elastic support part13being the gimbal. As a result, as compared to the case where capturing modules14a,14bare fixed to stepped surface part121b, even when movable body12moves and swings so as to be twisted about the X-axis, capturing modules14a,14bdoes not come into contact with the gimbal spring as elastic support part13. It is thus possible to increase the movable range of movable body12as compared to a camera module with a configuration where capturing module14is fixed to second stepped surface part (gimbal fixing part)121c.

Further, in the embodiment, two pairs being a pair of tilt coil112A and permanent magnets122A and a pair of tilt coil112C and permanent magnets122C are disposed as the voice coil motor that swings and rotates movable body12about the Y-axis, and two pairs being a pair of tilt coil112B and magnet coil122B and a pair of tilt coil112D and permanent coil122D are disposed as the voice coil motor that swings and rotates movable body12about the X-axis, but in each of the above two pairs, at least one pair may only be disposed.

To shake detection part15, it is possible to apply a photo reflector, a magnetic sensor, inductance detection by a coil, distortion sensor, or the like other than the gyro sensor. When the detection element (for example, a photodetector of a photo reflector, a hole element of a magnetic sensor, or the like) is disposed in the movable body, a detection signal is preferably output via the printed circuit board of the capturing module.

Each part constituting lens driving device1is preferably formed of a material with high heat resistance (especially magnet part122). It is thereby possible to deal with soldering performed by a reflow method. In addition, for noise reduction, a conductive shield case may be provided outside camera module100.

In the embodiment, the description has been given taking the smartphone that is a mobile terminal with a camera as the example of the camera-mounted device provided with camera module100, and the present invention can also be applied as a camera-mounted device that is an information device or a transporting device. For example, the present invention is also applicable, as the camera-mounted device, to a mobile phone with a camera, a laptop computer, a tablet terminal, mobile game machine, a web camera, and the like. Further, the present invention is also applicable, as the camera-mounted device, to an automobile, an on-vehicle device with a camera (for example, a rear-monitor device, a drive recorder device), and the like.FIGS. 10A and 10Billustrate automobile V mounted with an on-board camera module (vehicle camera).FIG. 10Ais a front view of automobile V, andFIG. 10Bis a rear perspective view of automobile V. Automobile V is mounted with camera module100described in the embodiment as on-board camera module VC. This on-board camera module VC is used for back monitoring, drive recording, collision avoidance control, automatic drive control, and the like.

The embodiment disclosed this time should be considered as illustrative in all aspects rather than restrictive. The scope of the invention is represented by the claims rather than the above description, and is intended to include meanings equivalent to the claims and all changes within the claims.

The entire contents of disclosure of the specification, drawings, and abstracts included in Japanese Patent Application No. 2016-150294 filed Jul. 29, 2016 are incorporated herein by reference in their entirety.

INDUSTRIAL APPLICABILITY

An actuator, a camera module, and a camera-mounted device according to the present invention can be reduced in size and cost and has the effect of achieving a dual camera without an error of camera-shake correction, and is useful as an device applicable to an information device including a mobile terminal such as a smartphone, a transporting device such as an automobile, an on-vehicle device with a camera, and the like.

REFERENCE SIGNS LIST