JP6563547B2 - Lens drive device - Google Patents

Description

   The present invention relates to a lens driving device suitably used for a camera module of a mobile phone, for example.

   In a lens driving device suitably used for a mobile phone camera module or the like, a lens holder is sandwiched between a pair of ring-shaped spring plates arranged in the optical axis direction so that a focusing operation or the like can be performed. It has been proposed (see Patent Document 1).

   In the lens driving device according to the prior art, the lens group held by the lens holder can only perform a focusing operation. For example, in order to give the lens driving device other functions such as a blur correction, the blur correction operation is performed. It was necessary to incorporate a lens group for use separately. Therefore, it has been difficult to realize a small and multifunctional lens driving device with the prior art.

JP 2004-280031 A

   The present invention has been made in view of such a situation, and an object thereof is to provide a small and multifunctional lens driving device.

In order to achieve the above object, a lens driving device according to the present invention includes:
A lens portion including at least one lens;
A first drive unit that moves the lens unit relative to the base unit along a direction perpendicular to the optical axis of the lens unit;
A second driving unit that moves the lens unit relative to the base unit along the optical axis.

   The lens driving unit according to the present invention includes a first driving unit that moves the lens unit along a direction perpendicular to the optical axis, and a second driving unit that moves the lens unit along the optical axis. Can also serve as a focus adjustment lens and a blur correction lens. Therefore, the lens driving device according to the present invention can realize a small and multifunctional lens driving device.

Also, for example, the lens driving device according to the present invention is
A focus unit including the lens unit and the second drive unit;
The first drive unit may move the focus unit relative to the base unit along a direction perpendicular to the optical axis.

   Since the 1st drive part in such a lens drive device moves the whole focus part containing a lens part and the 2nd drive part, the structure of the 1st drive part and the 2nd drive part can be simplified. Further, the first driving unit moves the entire focusing unit along a direction perpendicular to the optical axis, and the second driving unit moves the lens unit along the optical axis. Moved in the direction. Such a lens driving device is easier to control than a lens driving device that directly moves the lens portion in a three-dimensional direction.

   In addition, for example, the first driving unit includes a first magnet attached to the focus unit, and a first coil attached to the base unit and disposed to face the first magnet. But you can.

   Since the first driving unit in such a lens driving device includes a voice coil motor constituted by the first magnet and the first coil, the lens unit included in the focusing unit can be accurately aligned along the direction perpendicular to the optical axis. Can move well.

Further, for example, the lens driving device according to the present invention may include at least three suspension wires,
The focus part and the base part may be connected to each other by the at least three suspension wires so as to be relatively movable.

   In such a lens driving device, since the focus portion and the base portion are connected to each other by at least three suspension wires so as to be relatively movable, the structure is simple.

Further, for example, the focus unit may include a focus base that is moved relative to the lens unit by the first drive unit, and a spring that connects the focus base and the lens unit so as to be relatively movable. ,
The second drive unit may include a second coil attached to the lens unit, and a second magnet attached to the focus base and arranged to face the second coil.

   Since the second driving unit in such a lens driving device includes a voice coil motor constituted by the second magnet and the second coil, the lens unit included in the focusing unit can be moved along the optical axis with high accuracy. Can do.

   Further, for example, one end of at least one suspension wire included in the at least three suspension wires is electrically connected to the second coil via the spring, and the at least one suspension wire The other end may be electrically connected to an external connection substrate included in the base portion.

   Since such a lens driving device can supply electric power from the base portion to the second coil via at least one suspension wire, the structure is simple and suitable for miniaturization.

The spring may include a B spring disposed on the base portion side of the lens portion and an F spring disposed on the lens portion on the opposite side of the base portion.
One end of the at least one suspension wire may be electrically connected to the second coil via the F spring.

   In such a lens driving device, the length of the suspension wire can be increased to support the focus portion with an appropriate force, and the movable range of the focus portion can be increased.

The at least three suspension wires may be constituted by four suspension wires,
The first driving unit can move the focus unit in an X direction and a Y direction perpendicular to the optical axis and orthogonal to each other,
The four suspension wires may have substantially the same rigidity in the X direction and in the Y direction.
The at least three suspension wires may have a substantially round cross-sectional shape.

   In such a lens driving device, when the focus unit is driven by the first driving unit, the primary resonance frequencies in the X direction and the Y direction are equal, and the control of the first driving unit in a camera shake operation or the like is easy. Further, by making the cross section of the suspension wire substantially round, the rigidity of the suspension wire 31 becomes substantially uniform with respect to the rotation direction around the axis of the suspension wire, so that the assembly of the suspension wire is facilitated.

   In addition, for example, a lens driving device according to the present invention includes a magnetic plate that is attached to the focus unit, is disposed between the first magnet and the second magnet, and is made of a magnetic material. May be included.

   The magnetic material plate disposed between the first magnet and the second magnet can block the magnetism between the first magnet and the second magnet and prevent the mutual magnetic fields from interfering with each other. Therefore, the lens driving device including such a magnetic plate can drive the lens with high accuracy.

Further, for example, the magnetic plate may have a ring shape whose outer periphery is substantially rectangular,
The first magnet may be constituted by four bar-shaped magnets arranged so as to correspond to each side of the magnetic plate as viewed in the optical axis direction,
The second magnet may be composed of four individual magnets arranged so as to correspond to the respective corners of the magnetic plate as viewed in the optical axis direction.

   By configuring the first magnet with rod-shaped magnets arranged so as to correspond to the respective sides of the magnetic plate, the first driving unit can generate a larger driving force. On the other hand, the lens holding device can include a lens having a larger diameter by configuring the second magnet with individual magnets arranged so as to correspond to each corner of the magnetic plate. . Therefore, such a lens driving device is suitable for further miniaturization.

   Preferably, an image sensor for detecting light incident through the lens unit is fixed to the base unit. By fixing the image sensor to the base portion, it is possible to move the lens portion in a direction perpendicular to the optical axis and a direction along the optical axis with respect to the image sensor. That is, the lens unit is held so as to be freely movable in three axis (three-dimensional) directions with respect to the image sensor.

   In the structure in which the image sensor is attached to the lens part (movable part) instead of the base part (fixed part), one end of a flexible printed circuit board (FPC) is attached to the movable part in order to take out an output signal from the image sensor. And the other end of the FPC needs to be connected to the fixed portion. In such a structure, since the movable portion and the fixed portion are connected by the FPC, there is a risk of suppressing the movement of the lens portion that is the movable portion with respect to the fixed portion, and the accuracy of camera shake correction control is reduced. There is a fear. Further, when the FPC is bent or stretched in accordance with the movement of the lens unit, a noise signal is generated. Also in this respect, there is a possibility that the accuracy of the camera shake correction control is lowered.

   On the other hand, in the present invention, by fixing the image sensor to the base part (fixed part), it is not necessary to connect the movable part and the fixed part with an FPC for transferring image data. As a result, the movement of the lens unit, which is a movable unit with respect to the fixed unit, can be smoothed, and noise signals generated due to bending of the FPC can be suppressed, thereby improving the accuracy of camera shake correction control. Can do. Further, by fixing the image sensor to the base portion (fixing portion), the lens driving device can be easily assembled, which contributes to a reduction in manufacturing cost.

FIG. 1 is an exploded perspective view of a camera unit including a lens driving device according to an embodiment of the present invention. FIG. 2 is a partial assembly diagram showing the arrangement of components around the camera shake correction voice coil motor in the camera unit shown in FIG. 3 is a perspective view of the camera unit shown in FIG. FIG. 4 is a schematic plan view illustrating the configuration of the camera shake correction voice coil motor included in the camera unit shown in FIG. FIG. 5 is a schematic cross-sectional view of the camera unit shown in FIG.

First Embodiment FIG. 1 is an exploded perspective view of a camera unit 44 including a lens driving unit 42 according to an embodiment of the present invention. The camera unit 44 includes a lens driving unit 42 and an image sensor unit 46. In the description of the camera unit 44, as shown by the coordinates shown in FIGS. In the following description, it is assumed that the direction toward the Z axis is the positive direction of the Z axis and the directions perpendicular to the optical axis L of the lens unit 21 are the X axis direction and the Y axis direction. The X axis, Y axis, and Z axis are perpendicular to each other.

   The image sensor unit 46 includes the filter 13, the bracket 12, the image sensor 11, the image sensor substrate 10, and the like. The image sensor 11 is composed of a solid-state imaging device such as a CCD or a CMOS, and generates an image signal by photoelectric conversion. The image sensor 11 is attached to the surface of the image sensor substrate 10 on the Z axis positive direction side. An image signal generated by the image sensor 11 is transmitted to a calculation unit, a storage unit, and the like via the image sensor substrate 10.

   A bracket 12 and a filter 13 are arranged on the positive side of the image sensor 11 in the Z-axis direction. The bracket 12 is fixed to the image sensor substrate 10, and the light receiving surface of the image sensor 11 is protected by the bracket 12 and the filter 13. The bracket 12 is formed with a rectangular through-hole so that photographing light can be transmitted. The filter 13 is made of a transparent material, and is attached to the bracket 12 so as to close the through hole of the bracket 12.

   A lens driving unit 42 is disposed on the Z-axis positive direction side of the image sensor unit 46. The lens drive unit 42 according to the present embodiment includes a focus unit 20 including a lens unit 21 and an AF voice coil motor 38, a magnetic material plate 34, a camera shake correction voice coil motor 39, a suspension wire 31, and a base unit 40. including.

As shown in FIG. 1, the base portion 40 is disposed on the positive side of the bracket 12 in the Z-axis positive direction. The base unit 40 includes a unit board 33 and a circuit board 32. The unit board 33 preferably has an appropriate strength so as to support the circuit board 32, the suspension wire 31 and the like installed on the positive side of the unit board 33 in the Z-axis direction. The material of the unit substrate 33 is not particularly limited, and for example, a resin material such as LCP (Liquid Crystal Polymer) can be used. The unit substrate 33 is fixed to the bracket 12. Therefore, the base portion 40 including the unit substrate 33 is fixedly attached to the image sensor unit 46 including the image sensor 11 so as not to move relative to the image sensor 11.

   The circuit board 32 has wiring for transmitting an electrical signal to the AF voice coil motor 38 and the camera shake correction voice coil motor 39. The circuit board 32 is configured by, for example, an FPC (flexible printed circuit board). The circuit board 32 is fixed to the unit board 33 by adhesion or the like and supported by the unit board 33.

   The circuit board 32 is electrically connected to a drive control unit (not shown) provided outside the lens drive unit 42. In other words, the circuit board 32 serves as an external connection board that relays the electronic components inside the lens driving unit 42 and the drive control unit. The drive control unit drives and controls the AF voice coil motor 38 and the camera shake correction voice coil motor 39 so that the autofocus operation and the camera shake correction operation are appropriately realized. For example, in the AF coil 23 (second coil), the X-direction camera shake correction coil (first coil) 36x, and the Y-direction camera shake correction coil (first coil) 36y, a control signal from the drive control unit passes the circuit board 32. Communicated through.

   The circuit board 32 is provided with an X direction position sensor 35x and a Y direction position sensor 35y. The X direction position sensor 35 x and the Y direction position sensor 35 y detect the relative position of the focus unit 20 with respect to the base unit 40. The X direction position sensor 35x and the Y direction position sensor 35y are configured by, for example, Hall elements. The X direction position sensor 35x and the Y direction position sensor 35y detect a change in the magnetic field due to the movement of the X direction camera shake correction magnet 37x and the Y direction camera shake correction magnet 37y attached to the focus unit 20, and detect the position of the focus unit 20. .

   The suspension wire 31 connects the base portion 40 and the focus portion 20 so as to be relatively movable. The lens driving unit 42 according to the present embodiment includes four suspension wires 31. The material of the suspension wire 31 is not particularly limited, but phosphor bronze is preferable.

   The number of suspension wires 31 used in the lens driving unit 42 is preferably three or more in order to connect and support the base portion 40 and the focus portion 20 with a good balance. In the present embodiment, the suspension wires 31 are disposed at the four corners of the lens driving unit 42 having a substantially rectangular shape when viewed from the Z-axis direction. One end portion of each suspension wire 31 is fixed to the circuit board 32 or the unit substrate 33 of the base portion 40, and the other end portion of each suspension wire is the cap 27 or the F spring 24 included in the focus portion 20. It is fixed to. By fixing the suspension wire 31 to the cap 27 or the F spring 24 arranged at the end on the positive side of the Z axis in the focus portion 20, the length of the suspension wire 31 is increased and the focus portion 20 is applied with an appropriate force. Can be supported, and the movable range in the XY direction can be increased.

Further, in the present embodiment, the base portion 40 and the focus portion 20 are connected by four suspension wires 31, and these four suspension wires have substantially the same rigidity in the X-axis direction and in the Y-axis direction. By adopting such a configuration, the primary resonance frequency in the X-axis direction and the Y-axis direction when the focus unit 20 is driven by a camera shake correction voice coil motor 39 to be described later becomes substantially equal. The relative position control of the focus unit 20 is facilitated. Further, by making the cross-sectional shape of the suspension wire 31 substantially circular, such as a circle or a polygon close to a circle, the rigidity of the suspension wire 31 is substantially uniform with respect to the rotation direction around the axis of the suspension wire. Therefore, the assembly of the suspension wire 31 is facilitated.

   In the lens driving unit 42 according to this embodiment, one end of the two suspension wires 31 among the four suspension wires 31 is electrically connected to the AF coil 23 via the F spring 24. . The other ends of the two suspension wires 31 are electrically connected to the circuit board 32.

   That is, in the present embodiment, the F spring 24 is electrically divided into two. One end of the AF coil 23 shown in FIG. 1 is electrically connected to one of the divided F springs 24, and is electrically connected to one end of the suspension wire 31 via one of the F springs 24. . On the other hand, the other end of the AF coil 23 is electrically connected to the other of the divided F springs 24, and the suspension wire 31 to which the AF coil 23 is connected via the other of the F springs 24. Are electrically connected to one end of another different suspension wire 31. Therefore, the lens driving unit 42 according to the present embodiment can supply power to the AF coil 23 from the circuit board 32 of the base portion 40 via the two suspension wires 31.

   On the Z axis positive direction side of the base portion 40, a camera shake correction voice coil motor 39 is disposed. The camera shake correction voice coil motor 39 moves the lens unit 21 relative to the base unit 40 along a direction perpendicular to the optical axis L of the lens unit 21. The camera shake correction voice coil motor 39 according to the present embodiment moves the lens unit 21 relative to the base unit 40 by moving the entire focus unit 20 including the lens unit 21 and the AF voice coil motor 38.

   The camera shake correction voice coil motor 39 includes an X direction camera shake correction magnet 37x and a Y direction camera shake correction magnet 37y that are attached to the focus unit 20 via the magnetic plate 34, and an X direction camera shake correction coil 36x and Y that are attached to the base unit 40. A direction image stabilization coil 36y is included. An X-direction image stabilization coil 36x is arranged on the Z-axis negative direction side of the X-direction image stabilization magnet 37x so as to face the X-direction image stabilization magnet 37x. In addition, a Y-direction image stabilization coil 36y is arranged on the negative side of the Z-axis of the Y-direction image stabilization magnet 37y so as to face the Y-direction image stabilization magnet 37y.

   The camera shake correction voice coil motor 39 includes four coils 36x and 36y constituted by two X direction camera shake correction coils 36x and two Y direction camera shake correction coils 36y, two X direction camera shake correction magnets 37x, and Y direction camera shake correction. It includes four magnets 37x and 37y constituted by the magnet 37y. Each coil 36 is supplied with a current from the circuit board 32 for driving a camera shake correction voice coil motor 39.

   A magnetic plate 34 is disposed on the Z axis positive direction side of the camera shake correction voice coil motor 39. The magnetic plate 34 is attached to the focus unit 20 and is fixed to the magnet holding member 25 in this embodiment. The magnetic material plate 34 is made of a magnetic material such as iron or stainless steel.

   As shown in FIG. 1, the magnetic plate 34 includes an AF magnet 26 disposed on the Z-axis positive direction side of the magnetic plate 34, and the X direction and Y disposed on the Z-axis negative direction side of the magnetic plate 34. It arrange | positions between the direction camera shake correction magnets 37x and 37y. Therefore, the magnetic plate 34 blocks the magnetism between the magnets 37x and 37y included in the camera shake correction voice coil motor 39 and the magnet 26 included in the AF voice coil motor 38, thereby preventing the mutual magnetic fields from interfering with each other. To do.

   In the present embodiment, the magnetic plate 34 has a ring shape whose outer periphery is substantially rectangular. Further, the magnets 37x and 37y included in the camera shake correction voice coil motor 39 are composed of bar-shaped magnets, and the magnets 37x and 37y are arranged so as to correspond to the respective sides of the magnetic plate 34.

   FIG. 2 is a partial assembly diagram showing the arrangement of components around the camera shake correction voice coil motor 39 in the camera unit 44 shown in FIG. The magnets 37x, 37y and the coils 36x, 36y included in the camera shake correction voice coil motor 39 shown in FIG. 1 are arranged as shown in FIG. Note that FIG. 2 does not illustrate the focus unit 20.

   In FIG. 2, the magnetic material plate 34 and the X-direction and Y-direction image stabilization magnets 37x and 37y fixed to the magnetic material plate 34 are not fixed to the other members shown in FIG. That is, in the camera unit 44 shown in FIG. 1, the camera shake correction voice coil motor 39 moves the focus unit 20 installed on the Z axis positive direction side of the magnetic plate 34 to the image sensor unit 46 and the base unit 40. Relative movement in the direction along the XY plane.

   As shown in FIG. 1, the focus unit 20 is installed on the positive side of the magnetic material plate 34 in the Z-axis direction. The focus unit 20 includes a lens unit 21, an AF voice coil motor 38, an F spring 24, a B spring 29, a focus base 48, a coil holder 22, and the like.

   The focus base 48 according to this embodiment includes the magnet holding member 25 and the cap 27. An AF magnet 26 included in the AF voice coil motor 38 is fixed to the magnet holding member 25. Further, an X-direction camera shake correction magnet 37 x and a Y-direction camera shake correction magnet 37 y are also attached to the magnet holding member 25 via the magnetic material plate 34.

   Further, the cap 27 and the magnet holding member 25 are fixed to each other after the camera unit 44 is assembled as shown in FIG. The cap 27 may be attached to the magnet holding member 25 via the F spring 24 and the insulating sheet 30 shown in FIG.

   As shown in FIG. 1, the lens unit 21 and the AF voice coil motor 38 are housed inside the focus base 48. The lens unit 21 includes at least one lens, and forms an image by photographing light on the light receiving surface of the image sensor 11 arranged on the Z axis positive direction side of the lens unit 21.

   The AF voice coil motor 38 moves the lens unit 21 relative to the base unit 40 along the optical axis L of the lens unit 21. Here, the AF voice coil motor 38 according to the present embodiment moves the lens unit 21 relative to the focus base 48 in the optical axis direction. However, as will be described later, the focus base 48 is connected and supported to the base portion 40 by the suspension wire 31. For this reason, the AF voice coil motor 38 moves the lens unit 21 relative to the focus base 48, and as a result, moves the lens unit 21 relative to the base unit 40 and the image sensor 11. it can.

   The AF voice coil motor 38 includes an AF coil 23 attached to the lens unit 21 and an AF magnet 26 attached to the focus base 48. As shown in FIG. 1, the AF magnet 26 is fixed to the magnet holding member 25 and disposed so as to face the AF coil 23 after assembly. The AF magnet 26 includes four individual magnets, and each individual magnet is disposed so as to surround the AF magnet 26 along the circumferential direction of the lens unit 21. The individual magnets constituting the AF magnet 26 are arranged so as to correspond to the respective corners of the magnetic plate 34 in the optical axis direction (Z-axis direction).

   The AF coil 23 may be directly fixed to the lens unit 21, but may be fixed via the coil holder 22 like the lens driving unit 42 according to the present embodiment. The coil holder 22 has a hollow cylindrical shape, and has a portion for fixing the lens portion 21 and a portion for fixing the AF coil 23. The polygonal (octagonal) AF coil 23 can be securely attached to the cylindrical lens portion 21 by the coil holder 22.

   The lens driving unit 42 according to the present embodiment includes a B spring 29 attached to the base portion 40 side (Z-axis negative direction side) of the lens portion 21 and a side opposite to the base portion 40 of the lens portion 21 (Z-axis positive side). F springs 24 attached to the direction side). As shown in FIG. 5, the B spring 29 and the F spring 24 connect the focus base 48 and the lens unit 21 so as to be relatively movable along the optical axis direction L of the lens unit 21. As shown in FIG. 1, the F spring 24 includes an outer peripheral portion 24 a fixed to the focus base 48 and an inner peripheral portion 24 b fixed to the lens portion 21. The outer peripheral portion 24a may be directly fixed to the magnet holding member 25 or the cap 27 constituting the focus base 48, and is fixed to the AF magnet 26 fixed to the magnet holding member 25 via the insulating sheet 30. Thus, it may be indirectly fixed to the focus base 48.

   The inner peripheral part 24 b may be directly fixed to the lens part 21, but may be indirectly fixed to the lens part 21 by being fixed to the coil holder 22 fixed to the lens part 21. Similarly to the F spring 24, the B spring 29 is also directly or indirectly fixed to the focus base 48 and the lens unit 21. The B spring 29 and the F spring 24 are preferably made of an elastic material so that the focus base 48 and the lens unit 21 can be connected to each other so as to be relatively movable along the optical axis direction of the lens unit 21.

   The F spring 24 in the present embodiment is configured using an elastic material having conductivity. Although it does not specifically limit as a material which comprises F spring 24, For example, metal materials, such as copper, beryllium, or an alloy containing these, can be used. The inner peripheral portion 24 b of the F spring 24 is electrically connected to the AF coil 23 fixed to the coil holder 22. Therefore, the lens driving unit 42 according to the present embodiment can supply power to the AF coil 23 from the circuit board 32 of the base portion 40 via the two suspension wires 31 and the F spring 24.

One end of the AF coil 23 shown in FIG. 1 is electrically connected to one of the divided F springs 24, and is electrically connected to one end of the suspension wire 31 via one of the F springs 24. . On the other hand, the other end of the AF coil 23 is electrically connected to the other of the divided F springs 24, and the suspension wire 31 to which the AF coil 23 is connected via the other of the F springs 24. Are electrically connected to one end of another different suspension wire 31. Therefore, the lens driving unit 42 according to the present embodiment can supply power to the AF coil 23 from the circuit board 32 of the base portion 40 via the two suspension wires 31. In the case where power is supplied to the AF coil 23 via the F spring, it is preferable to sandwich the insulating sheet 30 between the magnet and the F spring 24.

   The cap 27 is attached to the Z axis positive direction side of the magnet holding member 25. The F spring 24, the AF voice coil motor 38, the lens unit 21, and the like are accommodated on the Z axis negative direction side of the cap 27. The other end of the suspension wire 31 is fixed to the cap 27 via the F spring 24 or directly. The camera unit 44 may have a cover 28 for covering the image sensor unit 46 and the lens driving unit 42.

   3 is a perspective view of the camera unit 44 shown in FIG. 1 after assembly. In FIG. 3, the cover 28 in FIG. 1 is not shown. The outer shape of the lens driving unit 42 is a rectangular parallelepiped shape, and suspension wires 31 are disposed at the four corners of the lens driving unit 42. One end of the suspension wire 31 is fixed to the base portion 40, and the other end of the suspension wire 31 is fixed to the magnet holding member 25 or the cap 27 of the focus base 48 as shown in FIG. .

   Since the suspension wire 31 supports between the focus base 48 and the base portion 40, the X-direction camera shake correction magnet 37 x attached to the focus base 48 of the focus portion 20 and the X attached to the base portion 40. The directional camera shake correction coil 36x is arranged to face each other with a slight gap in the Z-axis direction. Similarly, the Y-direction image stabilization magnet 37y and the Y-direction image stabilization coil 36y are also arranged to face each other with a slight gap in the Z-axis direction.

   4 is a schematic plan view for explaining the configuration of the camera shake correction voice coil motor 39. The positional relationship between the camera shake correction voice coil motor 39 and the image sensor 11 in FIG. 1 is observed from the Z axis positive direction side. It is. Two sets of X-direction image stabilization magnets 37x and coils 36x arranged with the image sensor 11 sandwiched in the X-axis direction move the entire focus unit 20 shown in FIG. 3 relative to the base unit 40 in the X-axis direction. Let

   Also, as shown in FIG. 4, two sets of Y-direction image stabilization magnets 37y and coils 36y arranged with the image sensor 11 sandwiched in the Y-axis direction, the entire focus section 20 shown in FIG. On the other hand, it is relatively moved in the Y-axis direction. Accordingly, the camera shake correction voice coil motor 39 can move the entire focus unit 20 shown in FIG. 3 relative to the base unit 40 in any direction along the XY plane.

   As shown in FIGS. 3 and 4, the X-direction position sensor 35x attached to the base portion 40 is connected to the X-direction image stabilization magnet 37x attached to the focus base 48, like the X-direction image stabilization coil 36x. On the other hand, they are arranged so as to face each other with a slight gap in the Z-axis direction. Further, the Y-direction position sensor 35y is also arranged to face each other with a slight gap in the Z-axis direction with respect to the Y-direction image stabilization magnet 37y.

   A drive control unit (not shown) that controls the lens drive unit 42 shown in FIG. 1 detects the position of the focus unit 20 or the lens unit 21 based on detection signals of the X direction position sensor 35x and the Y direction position sensor 35y. To do. The lens driving unit 42 according to the present embodiment can perform the camera shake correction operation with high accuracy by detecting the position of the lens unit 21 and driving the camera shake correction voice coil motor 39 based on the detected position.

FIG. 5 is a schematic cross-sectional view of the camera unit 44 observed through a cross section passing through the optical axis L and the VV line shown in FIG. In FIG. 5, the portion on the left side of the optical axis L toward the paper surface represents a cross section passing through the optical axis L and parallel to the XZ plane, and the portion on the right side of the optical axis L toward the paper surface represents the optical axis L. And a cross section through the suspension wire 31. FIG. 5 is a conceptual diagram for explaining the driving of the lens unit 21 in an easy-to-understand manner. In FIG. 5, the shape of each member is simplified and some members are not shown. doing.

   As shown in FIG. 5, the lens unit 21 is held by an F spring 24 and a B spring 29 so as to be movable relative to the focus base 48 along the optical axis L. The lens unit 21 is driven by an AF voice coil motor 38 so as to move relative to the focus base 48 along the optical axis L. The AF voice coil motor 38 includes an AF coil 23 attached to the lens unit 21 via the coil holder 22 and an AF magnet 26 attached to the magnet holding member 25 of the focus base 48.

   As described above, the lens drive unit 42 according to the present embodiment uses the F spring 24 and the B spring 29 to connect the focus base 48 and the lens unit 21 so as to be relatively movable, and the lens unit 21 and the focus base 48. An AF voice coil motor 38 is disposed between the two. As a result, the lens driving unit 42 according to the present embodiment can move the lens unit 21 along the optical axis L with high accuracy despite having a very simple structure.

   As shown in FIG. 5, in the lens driving unit 42 according to the present embodiment, the lens unit 21, the AF voice coil motor 38, and the focus base 48 constitute a focus unit 20 that can perform a focusing operation. That is, the AF voice coil motor 38 of the focus unit 20 can adjust the focal length of the camera unit 44 by moving the lens unit 21 relative to the base unit 40 along the optical axis L.

   The focus unit 20 is held by the four suspension wires 31 so as to be movable relative to the base unit 40 along a direction perpendicular to the optical axis L. The focus unit 20 is driven by a camera shake correction voice coil motor 39 so as to move relative to the base unit 40 along a direction perpendicular to the optical axis L. The image stabilization voice coil motor 39 includes X and Y direction image stabilization magnets 37x and 37y attached to the focus unit 20 through the magnetic plate 34, and X direction and Y direction image stabilization attached to the base unit 40. And correction coils 36x and 36y.

   As described above, the lens driving unit 42 according to the present embodiment uses the four suspension wires 31 to connect the focus unit 20 and the base unit 40 so as to be relatively movable, so that the focus unit 30 and the base unit 40 are connected to each other. A camera shake correction voice coil motor 39 is disposed between them. As a result, the lens driving unit 42 according to the present embodiment can move the lens unit 21 along the direction perpendicular to the optical axis L with high accuracy despite having a very simple structure.

   Therefore, the lens driving unit 42 according to the present embodiment can perform the camera shake correction by driving the lens unit 21 so as to cancel the camera shake applied to the camera unit 44 using the camera shake correcting voice coil motor 39. Furthermore, in the lens driving unit 42 according to the present embodiment, the camera shake correction voice coil motor 39 moves the entire focus unit 20 along a direction perpendicular to the optical axis L. Therefore, in the lens driving unit 42 according to the present embodiment, one lens unit 21 can also serve as a focus adjustment lens used for autofocus and the like and a camera shake correction lens. Therefore, the lens driving unit 42 according to the present embodiment can reduce the number of parts, simplify the structure, has high functionality, and is suitable for downsizing.

   As shown in FIG. 5, the X direction and Y direction camera shake correction magnets 37 x and 37 y are attached to the end of the focus unit 20 on the Z axis negative direction side via a magnetic plate 34. The magnetic plate 34 is made of a magnetic material, and is disposed between the X-direction and Y-direction camera shake correction magnets 37 x and 37 y and the AF magnet 26.

   The magnetic plate 34 can block the magnetism between the X direction and Y direction camera shake correction magnets 37x and 37y and the AF magnet 26 and prevent the mutual magnetic fields from interfering with each other. Therefore, the lens driving unit 42 according to the present embodiment can drive the lens unit 21 with high accuracy. In addition, due to the blocking effect of the magnetic plate 34, the X-direction and Y-direction camera shake correction magnets 37x and 37y and the AF magnet 26 can be disposed close to each other, which is also suitable for downsizing.

   As shown in FIGS. 1 and 5, the AF magnet 26 is constituted by four individual magnets arranged so as to correspond to the respective corners of the magnetic material plate 34. On the inner peripheral side of the AF magnet 26, an AF coil 23 must be disposed as shown in FIG. However, by disposing the AF magnet 26 at the corner, the lens driving unit 42 according to the present embodiment can include the lens portion 21 having a larger diameter, which is suitable for downsizing.

   As shown in FIGS. 1, 4 and 5, the X-direction and Y-direction image stabilization magnets 37 x and 37 y are configured by four bar magnets arranged so as to correspond to the respective sides of the magnetic material plate 34. ing. Here, the X direction and Y direction camera shake correction coils 36x and 36y are arranged not on the inner peripheral side but on the Z axis negative direction side with respect to the X direction and Y direction camera shake correction magnets 37x and 37y.

   Therefore, the lens driving unit 42 in the present embodiment can increase the driving force by enlarging the facing area between the magnet and the coil in the camera shake correction voice coil motor 39 while keeping the entire size small. From the point of view, it is suitable for downsizing. The camera shake correction voice coil motor 39 preferably has a driving force larger than that of the AF voice coil motor 38 in order to move the entire focus unit 20. The X-direction image stabilization magnet 37x is in-plane magnetized in the X-axis direction corresponding to the X-direction image stabilization coil 36x (see FIG. 5). Similarly, the Y-direction image stabilization magnet 37y is In-plane two-pole magnetization is performed in the Y-axis direction corresponding to the camera shake correction coil 36y.

   Further, one end of the two suspension wires 31 among the four suspension wires 31 shown in FIG. 1 is electrically connected to the AF coil 23 via the F spring 24 shown in FIG. The other ends of the two suspension wires 31 are electrically connected to the circuit board 32. Therefore, the lens driving unit 42 according to the present embodiment can supply power from the circuit board 32 of the base portion 40 to the AF coil 23 via the two suspension wires 31, and the structure is simple. Yes, suitable for miniaturization.

   Furthermore, in this embodiment, the image sensor 11 is fixed to the base portion 40 (fixed portion), so that the lens portion 21 is held so as to be freely movable in three axis (three-dimensional) directions with respect to the image sensor 11. The In addition, in this embodiment, it is not necessary to connect the movable part and the fixed part with an FPC for transferring image data, and the movement of the focus part 20 that is the movable part with respect to the image sensor 11 can be made smooth. In addition, noise signals generated due to bending of the FPC and the like can be suppressed, and the accuracy of camera shake correction control can be improved. Further, by fixing the image sensor 11 to the base portion 40 (fixed portion), the lens drive unit 42 can be easily assembled, which contributes to a reduction in manufacturing cost.

Other Embodiments In the above-described embodiments, the camera shake correction voice coil motor 39 moves the lens unit 21 and the AF voice coil motor 38. However, the lens driving unit according to the present invention is not limited to this. For example, in the lens driving unit, the AF voice coil motor may move the lens unit 21 and the camera shake correction voice coil motor. In the above-described embodiment, the voice coil motor is employed as the drive unit that moves the lens unit 21, but a drive unit other than the voice coil motor may be employed.

DESCRIPTION OF SYMBOLS 20 ... Focus part 21 ... Lens part 23 ... AF coil 24 ... F spring 25 ... Magnet holding member 26 ... AF magnet 27 ... Cap 29 ... B spring 30 ... Insulation sheet 31 ... Suspension wire 32 ... Circuit board 33 ... Unit board 35x, 35y ... Position sensors 36x, 36y ... Camera shake correction coils 37x, 37y ... Camera shake correction magnet 38 ... AF voice coil motor 39 ... Camera shake correction voice coil motor 40 ... Base section 42 ... Lens drive unit 44 ... Camera unit 46 ... Imaging element unit 48 ... focus base

Claims (6)

A lens portion including at least one lens;
A rectangular movable part including the lens part;
A fixed part including a circuit board capable of supplying electricity to the movable part;
A first drive unit that moves the movable unit relative to the fixed unit along a direction perpendicular to the optical axis;
A second drive unit that moves the lens unit relative to the fixed unit along the optical axis;
A lens driving device including: a holding unit that connects the movable unit and the fixed unit so as to be relatively movable in a direction perpendicular to the optical axis;
The magnet attached to the movable part is arranged at a corner of the movable part,
The elastic part connected to the holding part is electrically divided into at least two,
The circuit board in the fixed part is electrically connected to the coil of the second drive part through the holding part and the elastic part .   The lens driving device according to claim 1, wherein the holding portions are disposed at four corners of the lens driving device.   The lens driving device according to claim 1, wherein the fixing unit includes an image sensor that detects light incident through the lens unit.   The lens driving device according to claim 1, wherein the holding unit is configured by at least three suspension wires. A line connecting the said optical axis and the holding portion, the lens driving device according to any one of claims 1 to 4 wherein said magnet is present.   The lens driving device according to claim 1, wherein a shortest distance between the holding unit and the optical axis is longer than a shortest distance between the magnet and the optical axis.

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