JP2012255905A - Lens actuator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lens actuator used mainly for a camera, a mobile phone and the like, which can be simply manufactured.SOLUTION: A lens actuator includes a moving unit 31 capable of holding a lens; and second coils 52A and 52B disposed so as to face magnets 48A-48D of the moving unit 31. The second coils 52A and 52B are disposed so as to face only two surfaces of outside surfaces of the moving unit 31, and a long axis direction of the second coil 52A is not parallel with a long axis direction of the second coil 52B disposed so as to face another outside surface of the moving unit 31. The second coils 52A and 52B require only two surface layout, so that the layout is easily adjusted, and the lens actuator can be simply manufactured.

Description

  The present invention relates to a lens actuator mainly used for cameras, mobile phones and the like.

  In recent years, cameras and mobile phones have been proposed that use lens actuators equipped with a shake correction mechanism that mechanically suppresses lens vibration in order to suppress image and image disturbance due to camera shake during shooting. Yes.

  Such a conventional lens actuator will be described with reference to FIGS.

  FIG. 7 is a sectional view of a conventional lens actuator 20, and FIG. 8 is an exploded perspective view thereof. Here, the lens actuator 20 is composed of a movable unit 1, four coil holders 2A to 2D, a lower cover 3, four shafts 4, and an upper cover 5. When a camera shake or the like occurs, the movable unit 1 is shaken. It suppresses the disturbance of video and images by moving.

  The movable unit 1 includes a magnet holder 11, a lens holder 12 that is movable in the vertical direction with respect to the magnet holder 11, and an imaging body 13.

  Here, eight magnets 14 are fixed to the magnet holder 11 side by side in two stages on the front, back, left and right inner surfaces. Further, four magnets 15 slightly larger than the magnets 14 are fixed to the front, rear, left and right outer surfaces of the magnet holder 11.

  The lens holder 12 includes a circular hole 12 </ b> A for fixing the lens, and is housed inside the magnet holder 11. A first coil 16 is wound around the outer periphery of the lens holder 12 in two upper and lower stages, and the first coil 16 faces the magnet 14 disposed on the inner surface of the magnet holder 11.

  That is, in the movable unit 1, when a current flows through the first coil 16, an electromagnetic force is generated between the magnet 14 and the lens holder 12 can be moved up and down with respect to the magnet holder 11.

  An imaging element 17 is disposed on the upper surface of the imaging body 13. Here, a semiconductor element such as a CCD (Charge Coupled Device) image sensor or a CMOS (Complementary Metal Oxide Semiconductor) image sensor is used for the image sensor 17.

  The image sensor 17 is located below the center of the circular hole 12A, and by moving the lens holder 12 up and down, autofocus control can be performed to automatically adjust the image captured by the image sensor 17 or the focus of the image.

  The shafts 4 are erected at the four corners of the lower cover 3 and connected to the four corners of the upper surface of the magnet holder 11 of the movable unit 1, so that the movable unit 1 is swingably held on the lower cover 3. Further, the coil holders 2 </ b> A to 2 </ b> D are arranged on the front, rear, left and right of the movable unit 1, and the second coil 18 is arranged in a state of facing the magnet 15.

  That is, the movable unit 1 is swingably held by the four shafts 4, and when a shake such as a hand shake occurs in the lens actuator 20, a current is passed through the second coil 18, whereby the second coil The movable unit 1 is configured to swing by an electromagnetic force generated between the magnet 18 and the magnet 15.

  When an electronic device equipped with the lens actuator 20 is used, if a video or an image captured by the image sensor 17 is shaken due to camera shake or the like, the video or image captured by swinging the movable unit 1 is used. This is to perform shake correction control to correct the above.

  As prior art document information related to the invention of this application, for example, Patent Document 1 is known.

International Publication No. 2009/133691

  However, the conventional lens actuator 20 is manufactured by adjusting the positional relationship of the second coil 18 with respect to the magnet 15 and separately arranging the coil holders 2A to 2D on the front, rear, left and right of the movable unit 1. The time and effort required for adjusting the position are large.

  The present invention solves such a conventional problem, and an object thereof is to provide a lens actuator that can be easily manufactured.

  In order to achieve the above object, the present invention provides a lens that is arranged so that the second coil is arranged opposite to the two outer surfaces of the movable unit, and the major axis direction of the second coil is not parallel. An actuator is configured.

  According to the present invention, the second coil is disposed so as to face the two outer surfaces of the movable unit, the second coil is held so that the major axis direction is not parallel, the lens actuator is configured, Since the trouble of adjusting the positional relationship of the second coil is reduced by reducing the number of surfaces on which the second coil is disposed, a lens actuator that can be easily manufactured can be provided.

Sectional drawing of the lens actuator by one embodiment of this invention Exploded perspective view of the lens actuator Partial perspective view of the lens actuator An exploded perspective view of a movable unit used for the lens actuator FIG. 6 is a partial perspective view of a lens actuator according to another embodiment of the present invention. Top view combining the main parts of a lens actuator according to another embodiment A perspective sectional view of a conventional lens actuator Exploded perspective view

  Hereinafter, embodiments of the present invention will be described with reference to FIGS.

(Embodiment)
FIG. 1 is a sectional view of a lens actuator 70 according to an embodiment of the present invention, FIG. 2 is an exploded perspective view thereof, and FIG. 3 is a partial perspective view with an upper cover 36 and a flexible printed wiring board 35 removed. Here, the lens actuator 70 includes a movable unit 31, a coil unit 32, a lower cover 33, shafts 34A to 34D, a flexible printed wiring board 35, and an upper cover 36.

  The lens actuator 70 has, for example, a width in the left-right direction (Y-axis direction) of 5 mm to 20 mm, a depth in the front-rear direction (X-axis direction) of 5 mm to 20 mm, and a height in the vertical direction (Z-axis direction) of 2 mm to 10 mm. The width in the left-right direction and the depth in the front-rear direction are configured with substantially the same dimensions.

  First, the configuration of the movable unit 31 will be described. Here, FIG. 4 is a partially exploded perspective view of the movable unit 31.

  As can be seen from the sectional view of FIG. 1 and the exploded perspective view of FIG. 4, the movable unit 31 includes a lens holder 41, a magnet holder 42, a lower spring 43, and an upper spring 44.

  The lens holder 41 includes a carrier 45 and first coils 46 </ b> A and 46 </ b> B arranged on the outer periphery of the carrier 45 in two upper and lower stages.

  Here, the carrier 45 has a rectangular cylindrical shape with a circular hole 45A in the center, and is made of an insulating resin such as polycarbonate containing glass. Here, the diameter of the circular hole 45A may be constant or may be changed. Moreover, you may provide shapes, such as a screw for fixing a lens inside.

  The first coils 46 </ b> A and 46 </ b> B are formed by winding a coil wire such as an enamel wire having a wire diameter of Φ40 μm to Φ60 μm around the carrier 45 with the upper direction as an axis. Here, the upward direction coincides with the direction of the central axis of the circular hole 45A.

  The magnet holder 42 includes a holder 47, magnets 48A to 48D, and magnets 49A to 49D.

  Here, the holder 47 is formed of an insulating resin such as a glass-filled polycarbonate in a square cylinder shape having a square hole 47A in the center. Further, a holder-side rim portion 47B projecting in all directions is provided on the bottom surface of the holder 47, and a holder-side locking portion 47C is provided on the holder-side rim portion 47B as a substantially V-shaped groove.

  Further, on the side surfaces of the holder 47 in the front-rear and left-right directions, a slightly larger magnet 48A to 48D having a rectangular parallelepiped shape, and a slightly smaller magnet 49A to 49D having a rectangular parallelepiped shape, with the magnets 48A to 48D facing upward and the magnets 49A to 49D facing downward. And are fixed with an adhesive (not shown) or the like.

  Here, the magnets 48A to 48D and the magnets 49A to 49D are magnetized so that the magnetic poles on the inner side surfaces are different from each other, and accordingly, the magnetic poles on the outer side surfaces are also different from each other. Is so magnetized. For example, the inner surfaces of the magnets 48A to 48D are magnetized with the S pole, and the inner surfaces of the magnets 49A to 49D are magnetized with the N pole. Accordingly, the outer surfaces of the magnets 48A to 48D are magnetized with the N pole, and the outer surfaces of the magnets 49A to 49D are magnetized with the S pole.

  As described above, the magnets 48A to 48D and the magnets 49A to 49D arranged in the vertical direction are magnetized so that the magnetic poles on the inner side surface and the outer side surface are alternately different, so that the radiation direction of the magnetic field is rectified and stronger. It has a configuration capable of generating a magnetic field.

  Here, as the magnets 48A to 48D and the magnets 49A to 49D, neodymium magnets, which are rare earth magnets mainly composed of neodymium, iron, and boron, are used. The present invention can be implemented with magnets other than neodymium magnets, but since neodymium magnets have a large magnetic force, the current flowing through the first coils 46A and 46B can be reduced, which is advantageous in terms of power saving. . Further, it is desirable to use a neodymium magnet having a holding power of 500 kA / m to 3000 kA / m and a residual magnetic flux density of 1.3 to 1.5 T.

  Furthermore, since the inner side surfaces of the magnets 48A to 48D are magnetized with the S pole and the inner side surfaces of the magnets 49A to 49D are magnetized with the N pole, between the magnets 48A to 48D and between the magnets 49A to 49D, Repel each other. Therefore, it is desirable that the holder 47 be provided with side walls in contact with the magnets 48A to 48D and the magnets 49A to 49D outside the magnets 48A to 48D and the magnets 49A to 49D.

  The lens holder 41 is housed in the square hole 47A of the holder 47, and the first coils 46A and 46B are opposed to the magnets 48A to 48D and the magnets 49A to 49D.

  That is, in the movable unit 31, when a current flows through the first coils 46A and 46B, electromagnetic force is generated between the magnets 48A to 48D and the magnets 49A to 49D, and the lens holder 41 is movable up and down with respect to the magnet holder 42. It is configured to

  The lower spring 43 is a conductive metal leaf spring in which an outer peripheral portion 43A and an inner peripheral portion 43B are connected by a plurality of meandering spring portions 43C. The upper spring 44 is also a conductive metal leaf spring in which an outer peripheral portion 44A and an inner peripheral portion 44B are connected by a plurality of meandering spring portions 44C.

  The outer peripheral portion 43A and the outer peripheral portion 44A are fixed to the magnet holder 42, and the inner peripheral portion 43B and the inner peripheral portion 44B are fixed to the lens holder 41. Thereby, when the electric current is not flowing through the first coils 46 </ b> A and 46 </ b> B, the lens holder 41 can return to a predetermined position with respect to the magnet holder 42.

  Here, the movable unit 31 causes the lens holder 41 to move up and down with respect to the magnet holder 42 by passing a current through the first coils 46A and 46B, or the weight of the lens holder 41 and the lower spring 43 and upper spring 44. The lens holder 41 is stopped by balancing the spring force and electromagnetic force. When no current flows through the first coils 46 </ b> A and 46 </ b> B, the lens holder 41 returns to a predetermined position with respect to the magnet holder 42.

  Next, components other than the movable unit 31 will be described with reference to FIGS.

  Here, the coil unit 32 includes a base 51 and second coils 52A and 52B.

  The base 51 is a rectangular cylinder having a square hole 51A in the center, and is formed of an insulating resin or the like. Then, a T-shaped groove 51B is provided on two orthogonal side walls, and a rectangular groove 51C is provided on the remaining two side walls. The upper surface includes a plurality of base-side rim portions 51D protruding in four directions, and holes 51E in each of the base-side rim portions 51D.

  The second coils 52A and 52B are fixed to the groove 51B with an adhesive (not shown) or the like. The second coils 52A and 52B are coils formed by winding a coil wire having a wire diameter of Φ40 μm to Φ60 μm around the front-rear direction or the left-right direction. In addition, as a coil wire which forms the 2nd coils 52A and 52B, enamel wires, such as a polyurethane copper wire, a polyester copper wire, and a polyamide-type copper wire, are preferable.

  Here, the arrows A and B, which are the major axis directions of the second coils 52A and 52B, are arranged so as to be substantially orthogonal.

  The second coils 52A and 52B can be fixed by, for example, forming a resin bobbin and winding one coil wire directly around the bobbin, or forming an air-core coil and then bonding it to the base 51. There is a method of attaching with an agent. It is desirable to form an air-core coil from the viewpoint of miniaturization. In that case, it is desirable to use a self-bonding enameled wire and fuse the coil wires with hot air or alcohol to stabilize the shape.

  Alternatively, a printed coil can be used as the second coils 52A and 52B. A printed coil is a coil formed by film formation and patterning. Film formation includes formation methods such as vapor deposition, sputtering, ion plating, electroless plating, and electrolytic plating, and patterning includes a formation method that combines formation of a mask with a photoresist and etching. Examples of the procedure for producing a printed coil include a procedure for performing electrolytic plating after forming a copper thin film and performing patterning, and other than patterns after forming a mask with a photoresist on the copper thin film and performing electrolytic plating. There are procedures for removing the copper in this part by etching or the like. Etching may be dry etching or wet etching. Further, the printed coil may be formed on a printed circuit board, and in this case, the printed coil is not deformed during assembly, so that the assembling property is improved.

  The shafts 34A to 34D are conductive metal shafts. Here, the movable unit 31 is housed in the square hole 51 </ b> A of the base 51, the upper ends of the shafts 34 </ b> A to 34 </ b> D are locked to the holes 51 </ b> E of the base 51, and the lower ends are locked to the holder side locking portions 47 </ b> C of the holder 47. It is locked. The movable unit 31 is accommodated in the square hole 51A of the base 51 so that the magnets 48B and 48C face the second coils 52A and 52B.

  That is, the movable unit 31 is connected to the coil unit 32 via the shafts 34 </ b> A to 34 </ b> D, and the shafts 34 </ b> A to 34 </ b> D are configured to be able to move the movable unit 31 in the coil unit 32 while maintaining the horizontal level. ing.

  Further, since the magnets 48B and 48C are opposed to the second coils 52A and 52B, the movable unit 31 is movable in the coil unit 32 by electromagnetic force when a current is passed through the second coils 52A and 52B. It is.

  The flexible printed wiring board 35 is a flexible flexible printed wiring board provided with a connector 61 having a plurality of terminals on the end surface, and a plurality of wirings (not shown) are disposed therein. Then, it is folded three-dimensionally and further bent along the four side surfaces of the base 51. Two magnetic field detection elements 62A and 62B and two shake detection elements 63A and 63B are arranged on the surface where the flexible printed wiring board 35 is in contact with the outer surface of the base 51.

  The magnetic field detection elements 62A and 62B protrude into the groove 51B of the base 51, and the shake detection elements 63A and 63B protrude into the groove 51C.

  The magnetic field detection elements 62A and 62B and the two shake detection elements 63A and 63B are connected to the terminals on the end face of the connector 61 through the wiring in the flexible printed wiring board 35.

  Here, the magnetic field detection elements 62A and 62B are, for example, Hall elements that detect the strength of the magnetic field using the Hall effect. When the magnets 49B and 49C approach the magnetic field detection elements 62A and 62B, the magnetic fields detected by the magnetic field detection elements 62A and 62B become stronger, and when the magnets 49B and 49C move away from the magnetic field detection elements 62A and 62B, the magnetic field detection elements 62A and 62B. The magnetic field detected by is weakened.

  Thereby, when the movable unit 31 moves in the coil unit 32, the magnetic field detection element 62B can detect the position in the front-rear direction of the movable unit 31, and the magnetic field detection element 62A can detect the position in the left-right direction of the movable unit 31. It is configured.

  The shake detection elements 63A and 63B are elements that detect that the shake detection elements 63A and 63B are shaken, such as angular velocity sensors and acceleration sensors. Here, for example, when angular velocity sensors are arranged as the shake detection elements 63A and 63B, one detects an angular velocity in the yaw direction and the other in the pitch direction. For example, when an acceleration sensor is disposed as the shake detection elements 63A and 63B, one detects acceleration in the front-rear direction and the other in the left-right direction. Note that the shake detection elements 63A and 63B may not be uniaxial, but may be biaxial or triaxial, and other types of sensors may be arranged such that one is an angular velocity sensor and the other is an acceleration sensor.

  The surface of the flexible printed wiring board 35 on which the shake detection elements 63A and 63B are arranged is fixed to the base 51 with an adhesive (not shown). Since the shake detection elements 63A and 63B are fixed to the base 51 arranged outside the movable unit 31, it is possible to detect a change in posture when the lens actuator 70 shakes with high accuracy. It is.

  Note that the arrangement of the shake detection elements 63A and 63B is not necessarily orthogonal, but it is desirable that the angle formed by the arranged surfaces is 80 degrees or more and 100 degrees or less.

  The first coils 46A and 46B are electrically connected to terminals provided on the connector 61 of the flexible printed wiring board 35 through the lower spring 43, the upper spring 44, the shafts 34A to 34D, and the like. Moreover, the end of the coil wire which comprises the 2nd coils 52A and 52B is connected to the flexible printed wiring board 35, The 2nd coil 52A and the terminal provided in the connector 61 of the flexible printed wiring board 35 are connected. 52B is electrically connected.

  That is, the first coils 46 </ b> A and 46 </ b> B and the second coils 52 </ b> A and 52 </ b> B are both configured to allow current to flow through the terminals provided in the connector 61.

  The lower cover 33 is a metal plate made of a nonmagnetic material such as aluminum or white and white with a square hole 33A in the center. The lower cover 33 is attached to the lower surface of the base 51 with an adhesive (not shown). It is fixed with etc.

  The upper cover 36 has a circular hole 36A in the center, and is formed of a nonmagnetic material such as aluminum or white and white in a rectangular box shape with an open bottom surface. The upper cover 36 accommodates the movable unit 31, the coil unit 32, the shafts 34 </ b> A to 34 </ b> D, and the flexible printed wiring board 35 between the lower cover 33 and is fixed to the lower cover 33 by welding or the like. The circular hole 36A, the circular hole 45A, and the square hole 33A are continuous, and a through hole is formed from the upper surface to the lower surface of the lens actuator 70.

  Here, since both the upper cover 36 and the lower cover 33 are made of a non-magnetic material, the first coil 46A, 46B and the magnets 48A-48D, the magnets 49A-49D, or the second coil 52A. , 52B and the magnets 48B and 48C and the magnets 49B and 49C are restrained from affecting the electromagnetic force, so that the lens actuator 70 can be stably operated.

  A lens (not shown) is held in the circular hole 45A of the lens holder 41 of the lens actuator 70 configured as described above, and an imaging element (not shown) such as a CCD image sensor or a CMOS image sensor is provided below. Arranged and attached to electronic devices such as cameras and mobile phones.

  Then, the first coils 46A and 46B and the second coils 52A and 52B are connected to the electronic circuit (not shown) of the device via the terminals of the connector 61 and the like.

  In the lens actuator 70 configured as described above, for example, when a push button (not shown) for shutter of an electronic device is lightly pressed, a voltage is applied from the electronic circuit and a current flows through the first coils 46A and 46B. The lens holder 41 and the lens held in the circular hole 45A of the lens holder 41 move in the vertical direction, and autofocus control is performed to automatically focus the video or image.

  Further, when a camera shake or the like occurs when shooting is performed by further pressing the shutter push button, the vibration is detected by the electronic circuit by the shake detection elements 63A and 63B, and the electronic circuit is detected by the second coil. The current flowing through 52A and 52B is controlled to move the movable unit 31 in the front-rear or left-right direction, and shake correction control is performed.

  That is, in the lens actuator 70, the second coils 52A and 52B disposed facing the movable unit 31 are disposed on only two surfaces facing the outer surface of the movable unit 31, and the length of the second coil 52A. The movable unit is held in a positional relationship in which the axial direction is not arranged parallel to the major axis direction of the second coil 52B, and the second coils 52A and 52B are opposed to each other as compared with the conventional lens actuator 20. The number of outer surfaces of 31 is reduced and the arrangement becomes simple, so that the assemblability is improved and it can be easily manufactured.

  Further, since the second coils 52A and 52B are fixed with respect to the base 51, the second coils 52A and 52B can be combined with the outside of the movable unit 31 as one body, so that the assemblability is further improved.

  Further, since the shake detection elements 63A and 63B are built in the lens actuator 70, it is not necessary to arrange the same kind of shake detection element on the electronic device side, which contributes to downsizing of the electronic device.

  In addition, since the shake detection elements 63A and 63B are fixed to the base 51, the shake detection elements 63A and 63B improve the accuracy of detecting the shake and contribute to simple assembly of the lens actuator 70.

  Furthermore, since the outer surface of the movable unit 31 facing the shake detection elements 63A and 63B is arranged to be different from the outer surface of the movable unit 31 facing the second coils 52A and 52B, the shake detection elements 63A and 63B are arranged. It is possible to reduce the influence of 63B from the electromagnetic field generated by the current flowing through the second coils 52A and 52B, and vibrations such as camera shake can be detected with higher accuracy.

  As shown in the perspective view of FIG. 5, a plurality of second coils 72 </ b> A and 72 </ b> B in the upper stage and the second coils 73 </ b> A and 73 </ b> B in the lower stage arranged on the two surfaces of the base 71. Two coils may be arranged side by side. When the coils are arranged side by side in two upper and lower stages, the electromagnetic force increases, so that a large driving force can be obtained with a simple structure with respect to the movable unit 31.

  Moreover, it can replace with the structure of the said magnets 48A-48D and 49A-49D and the 2nd coils 52A and 52B, and can also be set as the structure shown by the top view of FIG.

  In FIG. 6A, the base 81 has a parallelogram-like prismatic shape when viewed from above, and magnets 82A to 82D are arranged on the four sides which are the outer sides of the base 81, and two of the magnets 82A and 82D are arranged on the two sides. The second coils 83A and 83B are arranged opposite to each other. As described above, the positional relationship between the second coils 83A and 83B is not limited as long as the directions of the arrows C and D as the major axis direction are not parallel to the second coil arranged on the other surface. It is not necessary.

  However, if the angle θ formed by the major axis direction of the second coils 83A and 83B becomes an obtuse angle or an acute angle, it is difficult to control the movement of the base 81 by flowing current independently through the second coils 83A and 83B. Therefore, the angle θ formed by the major axis direction of the second coils 83A and 83B is preferably 80 degrees or more and 100 degrees or less.

  Further, in FIG. 4B, magnets 92A to 92D are arranged on the four surfaces which are the outer surfaces of the base 91, and at least a part of the magnets 92A and 92D is overlapped in the top view. The second coils 93A and 93B are arranged.

  The magnets 92A to 92D may be arranged on the upper stage, the magnets 94A to 94D may be arranged on the lower stage, the second coil 93A may be arranged between the magnets 92A and 94A, and the second coil 93B may be arranged between the magnets 92D and 94D.

  Thus, even if the central axis of winding of the second coils 93A and 93B is in the vertical direction, the direction of the major-axis arrows E and F of the second coils 93A and 93B is not parallel. Implementation is possible.

  In the above description, the upper ends of the shafts 34A to 34D are connected to the coil unit 32 and the lower ends of the shafts 34A to 34D are connected to the movable unit 31, but the upper ends of the shafts 34A to 34D are connected to the movable unit. 31 may be configured such that the lower ends of the shafts 34 </ b> A to 34 </ b> D are connected to the coil unit 32.

  In addition, the video or image captured by the lens actuator 70 of the present invention may be a still image or a moving image.

  In the above description, the configuration in which the magnets 48A to 48D and 49A to 49D are arranged in parallel to the side surface of the upper cover 36 has been described. However, the magnets 48A to 48D and 49A to 49D are arranged at the four corner positions of the upper cover 36. It may be a configuration.

  When the magnetic field detection elements 62A and 62B used for detecting the position of the movable unit 31 are arranged so as to face an outer surface different from the outer surface of the movable unit 31 facing the second coils 52A and 52B. Since the influence of the electromagnetic field generated by the current flowing in the second coils 52A and 52B on the magnetic field detection elements 62A and 62B can be reduced, the position of the movable unit 31 can be detected with higher accuracy and the shake correction can be performed more accurately. Control can be performed.

  Further, the magnetic field detection elements 62A and 62B may be arranged at positions facing each other above or below the magnets 48A to 48D and 49A to 49D.

  That is, the magnetic field detection elements 62A and 62B are arranged so that the positional relationship in the front-rear or left-right direction changes with respect to the magnets 48A to 48D and 49A to 49D as the movable unit 31 moves.

  For example, the magnetic field detection elements 62A and 62B may be disposed above the magnets 48A and 48D with respect to the upper magnets 48A to 48D and the lower magnets 49A to 49D. Further, the magnetic field detection elements 62A and 62B may be disposed below the magnets 49A and 49D. Furthermore, magnetic field detection elements 62A and 62B may be arranged between the magnets 48A and 49A and between the magnets 48D and 49D.

  By arranging in this way, the position of the movable unit 31 can be detected with higher accuracy, and shake correction control can be performed more accurately.

  Further, the position detecting element for detecting the position of the movable unit 31 has been described as an element for detecting a magnetic field such as the magnetic field detecting elements 62A and 62B. However, an element using a method other than magnetic field detection, such as a photoreflector using infrared reflection. It may be.

  As described above, according to the present embodiment, the movable unit 31 that can hold the lens and the second coils 52A and 52B that are arranged to face the magnets 48B and 48C of the movable unit 31 are provided. 52A and 52B are disposed so as to face only two outer surfaces of the movable unit 31, and the arrow A which is the major axis direction of the second coil 52A is disposed so as to face the other outer surface of the movable unit 31. Since the lens actuator is configured to be held so as not to be parallel to the arrow B, which is the major axis direction of the second coil 52B, and the second coils 52A and 52B only need to be arranged on two sides, the arrangement can be adjusted. It is easy and can be easily manufactured.

  Moreover, since the base 51 further provided on the outer side of the movable unit 31 and the second coils 52A and 52B are fixed to the base 51, the second coils 52A and 52B are integrated with each other at the time of assembly. It can be handled and can be manufactured more easily.

  Further, since the shake detection elements 63A and 63B are provided and the shake detection elements 63A and 63B are fixed to the base 51, vibrations such as camera shake can be detected with high accuracy.

  Further, the shake detection elements 63A and 63B are arranged facing the outer surface of the movable unit 31, and the outer surface of the movable unit 31 facing the shake detection elements 63A and 63B is movable facing the second coils 52A and 52B. Since it is different from the outer surface of the unit 31, it is possible to reduce the influence of the shake detection elements 63A, 63B from the electromagnetic field generated by the current flowing in the second coils 52A, 52B, and to more accurately shake vibrations such as camera shake. It can be detected.

  The lens actuator according to the present invention can be easily manufactured, and is useful mainly for lens operation of a camera or a mobile phone.

31 movable unit 32 coil unit 33 lower cover 33A square hole 34A to 34D shaft 35 flexible printed wiring board 36 upper cover 36A, 45A circular hole 41 lens holder 42 magnet holder 43 lower spring 43A, 44A outer peripheral part 43B, 44B inner peripheral part 43C 44C Spring part 44 Upper spring 45 Carrier 46A, 46B First coil 47 Holder 47A Square hole 47B Holder side rim part 47C Holder side locking part 48A-48D, 49A-49D, 82A-82D, 92A-92D, 94A- 94D Magnet 51, 71, 81, 91 Base 51A Square hole 51B, 51C Groove 51D Base side rim 51E Hole 52A, 52B, 72A, 72B, 73A, 73B, 83A, 83B, 93A, 93B Second coil 61 Connector 62A 62B Field detection element 63A, 63B shake detecting element 70 lens actuator

Claims (4)

A carrier capable of holding a lens; a first coil wound around the carrier with the upper direction as an axis; and a front-rear and left-right direction of the first coil disposed opposite the first coil A movable unit comprising a magnet, and
A second coil disposed facing the movable unit, wherein the second coil is disposed facing only two of the outer surfaces of the movable unit, and the major axis direction of the second coil Is a lens actuator that is not parallel to the major axis direction of the second coil disposed facing the other outer surface of the movable unit. The lens actuator according to claim 1, further comprising a base disposed outside the movable unit, wherein the second coil is fixed to the base. The lens actuator according to claim 2, further comprising a shake detection element, wherein the shake detection element is fixed to the base. The shake detection element is disposed to face an outer surface of the movable unit, and an outer surface of the movable unit that the shake detection element faces is different from an outer surface of the movable unit that a second coil faces. 3. The lens actuator according to 3.

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