Lens drive device and camera module

Abstract

The present invention provides a lens driving device and a camera module. The lens driving device (101) includes a base member (18), an upper cover member (4U), a lens holding member (2), and a plurality of shape memory alloy wires (SA). The lens holding member (2) is disposed above the base member (18) and is movable relative to the base member (18) when current is applied to the shape memory alloy wires (SA). The lens holding member (2) has a plurality of first magnetic members (10) disposed at a plurality of different positions, and the base member (18) has a plurality of second magnetic members (MG) corresponding to the plurality of first magnetic members (10). Each of the plurality of first magnetic members (10) is attracted to the corresponding second magnetic member (MG), and when current is not applied to the shape memory alloy wires (SA), movement of the lens holding member (2) is restricted by the base member (18).

Description

[Technical field]

[0001] The present disclosure relates to a lens driving device. [Background technology]

[0002] Conventionally, a lens driving device using eight shape memory alloy wires is known (see Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2019 / 034860 Summary of the Invention [Problem to be solved by the invention]

[0004] In this lens driving device, when the shape memory alloy wire is not energized, the shape memory alloy wire is loose, and there is a risk that the lens holding member will move undesirably.

[0005] It is therefore desirable to provide a lens driving device that can prevent undesired movement of the lens holding member when the shape memory alloy wire is not energized. [Means for solving the problem]

[0006] A lens driving device according to one embodiment of the present invention is a lens driving device comprising: a fixed side member including a base member and a cover member; a lens holding member that is arranged in an accommodation space formed by the base member and the cover member and is capable of holding a lens body; and a plurality of shape memory alloy wires that are arranged between the fixed side member and a movable side member that includes the lens holding member, wherein the lens holding member is arranged on the upper side of the base member and is movable relative to the base member by passing current through the shape memory alloy wires, a plurality of first magnetic members are arranged at a plurality of different positions on the lens holding member, and a plurality of second magnetic members corresponding to the plurality of first magnetic members are provided on the base member, and each of the plurality of first magnetic members is facing the corresponding second magnetic member in the optical axis direction, The lens holding member is attracted to the corresponding second magnetic member, and the movement of the lens holding member is restricted by the base member when the shape memory alloy wire is not energized. Effect of the Invention

[0007] The above-described lens driving device can prevent undesired movement of the lens holding member when the shape memory alloy wire is not energized. [Brief description of the drawings]

[0008] [Figure 1A] 1A and 1B are perspective views of a lens driving device. [Figure 1B] 1A and 1B are perspective views of a lens driving device. [Diagram 2] FIG. 2 is an exploded perspective view of the lens driving device. [Figure 3A] 3A and 3B are perspective views of metal members connected to the lens holding member and the base member, respectively. [Figure 3B] 3A and 3B are perspective views of metal members connected to the lens holding member and the base member, respectively. [Figure 4A] 4A and 4B are diagrams of a metal member having a shape memory alloy wire attached thereto. [Figure 4B]4A and 4B are diagrams of a metal member having a shape memory alloy wire attached thereto. [Figure 5A] 5A to 5C are perspective views of the base member. [Figure 5B] 5A to 5C are perspective views of the base member. [Figure 5C] 5A to 5C are perspective views of the base member. [Figure 6A] 6A and 6B are diagrams showing the positional relationship between the leaf spring, the shape memory alloy wire, the metal member, and the conductive member. [Figure 6B] 6A and 6B are diagrams showing the positional relationship between the leaf spring, the shape memory alloy wire, the metal member, and the conductive member. [Figure 7A] 7A and 7B are diagrams showing an example of a path of a current flowing through a shape memory alloy wire. [Figure 7B] 7A and 7B are diagrams showing an example of a path of a current flowing through a shape memory alloy wire. [Figure 8A] 8A and 8B are diagrams showing an example of a connection structure for connecting a fixed metal member and a conductive member. [Figure 8B] 8A and 8B are diagrams showing an example of a connection structure for connecting a fixed metal member and a conductive member. [Figure 9A] 9A and 9B are diagrams showing an example of a connection structure for connecting a fixed metal member and a conductive member. [Figure 9B] 9A and 9B are diagrams showing an example of a connection structure for connecting a fixed metal member and a conductive member. [Figure 10] 2 is a perspective view of a lens holding member, an upper cover member, and a base member. FIG. [Figure 11A] 11A to 11C are detailed views of the lens holding member. [Figure 11B] 11A to 11C are detailed views of the lens holding member. [Figure 11C] 11A to 11C are detailed views of the lens holding member. [Figure 12A] 12A and 12B are a perspective view and a top view of the conductive member. [Figure 12B] 12A and 12B are a perspective view and a top view of the conductive member. [Figure 13A] 13A and 13B are top views of the lens holding member and the base member to which the first magnetic member is attached. [Figure 13B] 13A and 13B are top views of the lens holding member and the base member to which the first magnetic member is attached. [Figure 14A] 14A and 14B are cross-sectional views of the lens holding member, the first magnetic member, the base member, and the second magnetic member. [Figure 14B] 14A and 14B are cross-sectional views of the lens holding member, the first magnetic member, the base member, and the second magnetic member. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] A lens driving device 101 according to an embodiment of the present invention will be described below with reference to the drawings. Figures 1A and 1B are perspective views of the lens driving device 101. Specifically, Figure 1A is an upper perspective view of the lens driving device 101, and Figure 1B is a lower perspective view of the lens driving device 101. Figure 2 is an exploded perspective view of the lens driving device 101.

[0010] 1A, 1B, and 2, X1 represents one direction of the X axis constituting the three-dimensional orthogonal coordinate system, and X2 represents the other direction of the X axis. Y1 represents one direction of the Y axis constituting the three-dimensional orthogonal coordinate system, and Y2 represents the other direction of the Y axis. Similarly, Z1 represents one direction of the Z axis constituting the three-dimensional orthogonal coordinate system, and Z2 represents the other direction of the Z axis. In FIG. 1A, 1B, and 2, the X1 side of the lens driving device 101 corresponds to the front side (front side) of the lens driving device 101, and the X2 side of the lens driving device 101 corresponds to the rear side (rear side) of the lens driving device 101. The Y1 side of the lens driving device 101 corresponds to the right side of the lens driving device 101, and the Y2 side of the lens driving device 101 corresponds to the left side of the lens driving device 101. Moreover, the Z1 side of the lens driving device 101 corresponds to the upper side (subject side) of the lens driving device 101, and the Z2 side of the lens driving device 101 corresponds to the lower side (imaging element side) of the lens driving device 101. The same applies to the other figures.

[0011] 1A, 1B, and 2, the lens driving device 101 includes a cover member 4 that is a part of a fixed-side member RG. The cover member 4 includes an upper cover member 4U and a lower cover member 4L.

[0012] The cover member 4 is configured to function as a housing that covers each component. In this embodiment, the cover member 4 is made of a non-magnetic metal. However, the cover member 4 may be made of a magnetic metal. Also, as shown in Figs. 1A and 1B, the cover member 4 has a box-like outer shape that defines a storage section 4s.

[0013] The upper cover member 4U has a rectangular cylindrical first outer peripheral wall portion 4A and a rectangular annular flat top plate portion 4B provided so as to be continuous with the upper end (the end on the Z1 side) of the first outer peripheral wall portion 4A. A circular opening 4k is formed in the center of the top plate portion 4B. The first outer peripheral wall portion 4A includes a first side plate portion 4A1 to a fourth side plate portion 4A4. The first side plate portion 4A1 and the third side plate portion 4A3 face each other, and the second side plate portion 4A2 and the fourth side plate portion 4A4 face each other. The first side plate portion 4A1 and the third side plate portion 4A3 extend perpendicular to the second side plate portion 4A2 and the fourth side plate portion 4A4.

[0014] Similarly, the lower cover member 4L has a rectangular cylindrical second outer peripheral wall portion 4C and a rectangular annular flat bottom plate portion 4D provided so as to be continuous with the lower end (the end on the Z2 side) of the second outer peripheral wall portion 4C. A circular opening 4m is formed in the center of the bottom plate portion 4D. The second outer peripheral wall portion 4C includes a first side plate portion 4C1 to a fourth side plate portion 4C4. The first side plate portion 4C1 and the third side plate portion 4C3 face each other, and the second side plate portion 4C2 and the fourth side plate portion 4C4 face each other. The first side plate portion 4C1 and the third side plate portion 4C3 extend perpendicularly to the second side plate portion 4C2 and the fourth side plate portion 4C4.

[0015] 1A and 1B, the upper cover member 4U is joined to the lower cover member 4L by an adhesive. The second outer peripheral wall portion 4C is disposed so as to partially cover the first outer peripheral wall portion 4A.

[0016] As shown in FIG. 2, the cover member 4 accommodates the spacer member 1, the lens holding member 2, the metal member 5, the leaf spring 6, the base member 18, the shape memory alloy wire SA, and the like.

[0017] The movable member MB includes a lens holding member 2 capable of holding a lens body (not shown), a shape memory alloy wire SA as a drive mechanism MK for moving the lens holding member 2 along an optical axis JD related to the lens body, and a leaf spring 6 for supporting the lens holding member 2 movably along the optical axis JD. The lens body is, for example, a cylindrical lens barrel equipped with at least one lens, and is configured so that its central axis is aligned with the optical axis JD.

[0018] The spacer member 1 is arranged so as to prevent the lens holding member 2 made of synthetic resin from colliding with the cover member 4 made of metal when the lens holding member 2 moves in the Z1 direction. That is, the spacer member 1 is made of synthetic resin and arranged so as to form a space between the lens holding member 2 and the top plate portion 4B of the cover member 4. The spacer member 1 is fixed to the upper cover member 4U by an adhesive. Specifically, the spacer member 1 and the lens holding member 2 form a stopper portion that limits excessive movement of the lens holding member 2 in the Z1 direction (upward). In this embodiment, the lens holding member 2 is configured to come into contact with the spacer member 1 when it moves in the Z1 direction by a predetermined distance. With this configuration, the spacer member 1 prevents the lens holding member 2 made of synthetic resin from coming into contact with the upper cover member 4U made of metal, and prevents wear of the lens holding member 2 due to such contact. However, if a space can be formed between the lens holding member 2 and the top plate portion 4B of the upper cover member 4U by another structure or the like, the spacer member 1 may be omitted.

[0019] The lens holding member 2 is formed by injection molding a synthetic resin such as liquid crystal polymer (LCP). Specifically, as shown in FIG. 2, the lens holding member 2 includes a cylindrical portion 12 formed to extend along the optical axis JD, and a movable side base portion 2D and a protruding portion 2S formed to protrude radially outward from the cylindrical portion 12. In this embodiment, a thread groove is formed on the inner peripheral surface of the cylindrical portion 12 so that the lens body is screwed. The lens body may be configured to be fixed to the inner peripheral surface of the cylindrical portion 12 with an adhesive. In this case, the inner peripheral surface of the cylindrical portion 12 does not need to have a thread groove formed thereon.

[0020] The movable-side pedestal portion 2D includes a first movable-side pedestal portion 2D1 and a second movable-side pedestal portion 2D2. The first movable-side pedestal portion 2D1 and the second movable-side pedestal portion 2D2 are arranged to extend in opposite directions with the optical axis JD in between. Similarly, the protruding portion 2S includes a first protruding portion 2S1 and a second protruding portion 2S2. The first protruding portion 2S1 and the second protruding portion 2S2 are arranged to extend in opposite directions with the optical axis JD in between. Specifically, the movable-side pedestal portion 2D and the protruding portion 2S are arranged to correspond to the four corners of the lens holding member 2 having a substantially rectangular outer shape in a top view, and are arranged alternately. A part of the leaf spring 6 is placed on each of the two movable-side pedestal portions 2D.

[0021] The driving mechanism MK includes a shape memory alloy wire SA, which is an example of a shape memory actuator. In this embodiment, the shape memory alloy wire SA includes a first wire SA1 to an eighth wire SA8. When a current flows through the shape memory alloy wire SA, the temperature increases and the wire contracts in response to the increase in temperature. The driving mechanism MK can move the lens holding member 2 up and down along the optical axis JD by utilizing the contraction of the shape memory alloy wire SA. The shape memory alloy wire SA is configured such that when one or more of the first wire SA1 to the eighth wire SA8 contract, the lens holding member 2 moves, and the other one or more wires are stretched by the movement.

[0022] The leaf spring 6 is configured to support the lens holding member 2 movably in a direction parallel to the optical axis JD relative to the fixed member RG (base member 18). In this embodiment, the leaf spring 6 is made of a metal plate whose main material is, for example, a copper alloy, a titanium-copper alloy (titanium-copper), or a copper-nickel alloy (nickel-tin-copper). Specifically, the leaf spring 6 includes a first leaf spring 6A and a second leaf spring 6B.

[0023] The base member 18 is formed by injection molding using a synthetic resin such as liquid crystal polymer (LCP). In this embodiment, the base member 18 has a generally rectangular outline in top view, and has an opening 18K at the center, as shown in Fig. 5A. Specifically, the base member 18 has four sides 18E (first side 18E1 to fourth side 18E4) arranged to surround the opening 18K.

[0024] The leaf spring 6 is configured to connect a movable-side pedestal portion 2D formed on the lens holding member 2 and a fixed-side pedestal portion 18D formed on the base member 18. The fixed-side pedestal portion 18D includes a first fixed-side pedestal portion 18D1 and a second fixed-side pedestal portion 18D2.

[0025] More specifically, the first plate spring 6A is configured to connect the first movable-side pedestal portion 2D1 formed on the lens holding member 2 to each of the first fixed-side pedestal portion 18D1 and the second fixed-side pedestal portion 18D2 formed on the base member 18. Similarly, the second plate spring 6B is configured to connect the second movable-side pedestal portion 2D2 formed on the lens holding member 2 to each of the first fixed-side pedestal portion 18D1 and the second fixed-side pedestal portion 18D2 formed on the base member 18.

[0026] The metal member 5 is configured so that an end of the shape memory alloy wire SA is fixed. In this embodiment, the metal member 5 is formed of a non-magnetic metal, and includes a fixed-side metal member 5F and a movable-side metal member 5M. The fixed-side metal member 5F is configured so as to be fixed to the fixed-side pedestal portion 18D of the base member 18. The movable-side metal member 5M is configured so as to be fixed to the movable-side pedestal portion 2D of the lens holding member 2.

[0027] More specifically, the fixed metal member 5F is also referred to as a fixed terminal plate and includes a first fixed terminal plate 5F1 to an eighth fixed terminal plate 5F8. The movable metal member 5M is also referred to as a movable terminal plate and includes a first movable terminal plate 5M1 to a fourth movable terminal plate 5M4.

[0028] Next, the positional relationship between each of the lens holding member 2 and the base member 18 and the metal member 5 will be described with reference to Figures 3A and 3B. Figure 3A is a perspective view of the lens holding member 2 to which a movable side metal member 5M (movable side terminal plate) and a leaf spring 6 are attached. Figure 3B is a perspective view of the base member 18 to which a fixed side metal member 5F (fixed side terminal plate) is attached. For clarity, in Figure 3A, a dot pattern is applied to the movable side metal member 5M and the leaf spring 6, and in Figure 3B, a dot pattern is applied to the fixed side metal member 5F.

[0029] In the example shown in Fig. 3A, the first movable side terminal plate 5M1 is fixed to the Y1 side wall (right mounting surface) of the first movable side pedestal portion 2D1. Specifically, the first movable side terminal plate 5M1 is fixed to the first movable side pedestal portion 2D1 by an adhesive in a state in which a square-shaped protrusion 2V formed on the first movable side pedestal portion 2D1 and protruding outward (to the Y1 side) is engaged with a rectangular hole AH (see Fig. 4A) formed in the first movable side terminal plate 5M1. The adhesive is, for example, a light-curing adhesive. The light-curing adhesive is, for example, an ultraviolet-curing adhesive or a visible light-curing adhesive. Similarly, the second movable side terminal plate 5M2 is fixed to the X2 side wall (rear mounting surface) of the first movable side base portion 2D1, the third movable side terminal plate 5M3 is fixed to the X1 side wall (front mounting surface) of the second movable side base portion 2D2, and the fourth movable side terminal plate 5M4 is fixed to the Y2 side wall (left mounting surface) of the second movable side base portion 2D2.

[0030] In the example shown in FIG. 3B, the first fixed side terminal plate 5F1 and the second fixed side terminal plate 5F2 are fixed to the Y1 side wall (right mounting surface) of the first fixed side pedestal portion 18D1 arranged along the second side portion 18E2 of the base member 18. Specifically, the first fixed side terminal plate 5F1 and the second fixed side terminal plate 5F2 are fixed to the first fixed side pedestal portion 18D1 by an adhesive in a state in which two round protrusions 18V protruding outward (Y1 side) formed on the first fixed side pedestal portion 18D1 and through holes RH (see FIG. 4A) formed in each of the first fixed side terminal plate 5F1 and the second fixed side terminal plate 5F2 are engaged with each other. The adhesive is, for example, a photocurable adhesive. The photocurable adhesive is, for example, an ultraviolet-curable adhesive or a visible-light-curable adhesive. Similarly, the third fixed side terminal plate 5F3 and the fourth fixed side terminal plate 5F4 (not visible in FIG. 3B) are fixed to the X2 side wall (rear mounting surface) of the second fixed side pedestal portion 18D2 arranged along the third side portion 18E3 of the base member 18. The fifth fixed side terminal plate 5F5 and the sixth fixed side terminal plate 5F6 are fixed to the X1 side wall (front mounting surface) of the first fixed side pedestal portion 18D1 arranged along the first side portion 18E1 of the base member 18. The seventh fixed side terminal plate 5F7 and the eighth fixed side terminal plate 5F8 (not visible in FIG. 3B) are fixed to the Y2 side wall (left mounting surface) of the second fixed side pedestal portion 18D2 arranged along the fourth side portion 18E4 of the base member 18.

[0031] The shape memory alloy wires SA extend along the inner surface of the first outer circumferential wall portion 4A of the upper cover member 4U, and are configured to movably support the movable side member MB with respect to the fixed side member RG. In this embodiment, the shape memory alloy wires SA include the first wire SA1 to the eighth wire SA8, and are configured to movably support the lens holding member 2 as the movable side member MB with respect to the base member 18 as the fixed side member RG. As shown in FIG. 2, each of the first wire SA1 to the eighth wire SA8 has one end fixed to the fixed side metal member 5F by crimping, welding, or the like, and the other end fixed to the movable side metal member 5M by crimping, welding, or the like.

[0032] Next, the metal member 5 to which the shape memory alloy wire SA is attached will be described with reference to Figs. 4A and 4B. Fig. 4A is a view of the first wire SA1 attached to the first movable side terminal plate 5M1 and the first fixed side terminal plate 5F1, respectively, and the second wire SA2 attached to the first movable side terminal plate 5M1 and the second fixed side terminal plate 5F2, respectively, as viewed from the Y1 side. Fig. 4B is a view of the first wire SA1 attached to the first movable side terminal plate 5M1 and the first fixed side terminal plate 5F1, respectively, and the second wire SA2 attached to the first movable side terminal plate 5M1 and the second fixed side terminal plate 5F2, respectively, as viewed from the X1 side. The positional relationship of each member shown in Figs. 4A and 4B corresponds to the positional relationship when the lens driving device 101 is assembled. In Figs. 4A and 4B, other members are omitted from the illustration for clarity. Also, the following description with reference to Figures 4A and 4B relates to the combination of the first wire SA1 and the second wire SA2, but may be similarly applied to the combination of the third wire SA3 and the fourth wire SA4, the combination of the fifth wire SA5 and the sixth wire SA6, and the combination of the seventh wire SA7 and the eighth wire SA8.

[0033] Specifically, one end of the first wire SA1 is fixed to the first movable terminal plate 5M1 at a lower holding portion J3 of the first movable terminal plate 5M1, and the other end of the first wire SA1 is fixed to the first fixed terminal plate 5F1 at a holding portion J2 of the first fixed terminal plate 5F1. Similarly, one end of the second wire SA2 is fixed to the first movable terminal plate 5M1 at an upper holding portion J1 of the first movable terminal plate 5M1, and the other end of the second wire SA2 is fixed to the second fixed terminal plate 5F2 at a holding portion J4 of the second fixed terminal plate 5F2.

[0034] The holding portion J1 is formed by bending a part of the first movable terminal plate 5M1. Specifically, the part of the first movable terminal plate 5M1 is bent while sandwiching one end of the second wire SA2 to form the holding portion J1. The one end of the second wire SA2 is fixed to the holding portion J1 by welding. The same is true for the holding portions J2 to J4.

[0035] The first wire SA1 and the second wire SA2 are arranged so as to be twisted relative to each other, as shown in Fig. 4A. That is, the first wire SA1 and the second wire SA2 are arranged so as not to contact each other (to be non-contacting).

[0036] Next, the base member 18, which is a part of the fixed-side member RG, will be described in detail with reference to Figs. 5A to 5C. Figs. 5A to 5C are perspective views of the base member 18. Specifically, Fig. 5A is a perspective view of the base member 18 with the conductive member CM removed, Fig. 5B is a perspective view of the conductive member CM embedded in the base member 18, and Fig. 5C is a perspective view of the base member 18 with the conductive member CM embedded. Note that in Figs. 5B and 5C, dot patterns are applied to the conductive member CM for clarity.

[0037] The base member 18 is configured to function as a wire supporting member that supports one end of each of the first wires SA1 to the eighth wires SA8. With this configuration, the movable member MB is supported by the first wires SA1 to the eighth wires SA8 in a state in which it can move in the Z-axis direction, which is a direction parallel to the optical axis JD.

[0038] A fixed-side pedestal portion 18D is formed on the upper surface, which is the surface on the subject side (the surface on the Z1 side) of the base member 18. The fixed-side pedestal portion 18D includes a first fixed-side pedestal portion 18D1 and a second fixed-side pedestal portion 18D2. The first fixed-side pedestal portion 18D1 and the second fixed-side pedestal portion 18D2 are disposed to face each other across the optical axis JD.

[0039] A conductive member CM as shown in Fig. 5B is embedded in the base member 18 by insert molding. In this embodiment, the conductive member CM is made of a magnetic metal such as iron. The conductive member CM is configured to have a first terminal portion TM1 to an eleventh terminal portion TM11 that protrude from the lower surface (surface on the Z2 side) of the base member 18 and extend downward (in the Z2 direction), and a ninth bonding surface portion CP9 and a tenth bonding surface portion CP10 that are exposed on the upper surface (surface on the Z1 side) of the base member 18.

[0040] Specifically, the conductive member CM includes a first conductive member CM1 to an eleventh conductive member CM11. The first conductive member CM1 includes a first terminal portion TM1 and a first connection portion ED1. The second conductive member CM2 includes a second terminal portion TM2 and a second connection portion ED2. The third conductive member CM3 includes a third terminal portion TM3 and a third connection portion ED3. The fourth conductive member CM4 includes a fourth terminal portion TM4 and a fourth connection portion ED4. The fifth conductive member CM5 includes a fifth terminal portion TM5 and a fifth connection portion ED5. The sixth conductive member CM6 includes a sixth terminal portion TM6 and a sixth connection portion ED6. The seventh conductive member CM7 includes a seventh terminal portion TM7 and a seventh connection portion ED7. The eighth conductive member CM8 includes an eighth terminal portion TM8 and an eighth connection portion ED8. The ninth conductive member CM9 includes a ninth terminal portion TM9 and a ninth bonding surface portion CP9. The tenth conductive member CM10 includes a tenth terminal portion TM10 and a tenth bonding surface portion CP10. The eleventh conductive member CM11 includes an eleventh terminal portion TM11 and an eleventh connection portion ED11.

[0041] The first terminal portion TM1 to the fourth terminal portion TM4, the tenth terminal portion TM10, and the eleventh terminal portion TM11 are arranged along a third side portion 18E3 of the base member 18. The fifth terminal portion TM5 to the ninth terminal portion TM9 are arranged along a first side portion 18E1 of the base member 18.

[0042] That is, the first connection portion ED1 of the first conductive member CM1 is disposed along the second side portion 18E2 of the base member 18, and the first terminal portion TM1 of the first conductive member CM1 is disposed along the third side portion 18E3, not the second side portion 18E2, of the base member 18. Similarly, the second connection portion ED2 of the second conductive member CM2 is disposed along the second side portion 18E2 of the base member 18, and the second terminal portion TM2 of the second conductive member CM2 is disposed along the third side portion 18E3, not the second side portion 18E2, of the base member 18.

[0043] Further, the seventh connection portion ED7 of the seventh conductive member CM7 is disposed along the fourth side portion 18E4 of the base member 18, and the seventh terminal portion TM7 of the seventh conductive member CM7 is disposed along the first side portion 18E1 rather than the fourth side portion 18E4 of the base member 18. Similarly, the eighth connection portion ED8 of the eighth conductive member CM8 is disposed along the fourth side portion 18E4 of the base member 18, and the eighth terminal portion TM8 of the eighth conductive member CM8 is disposed along the first side portion 18E1 rather than the fourth side portion 18E4 of the base member 18.

[0044] In this manner, the first terminal portion TM1 to the eleventh terminal portion TM11 are arranged along the first side portion 18E1 or the third side portion 18E3 of the base member 18, and are not arranged along the second side portion 18E2 and the fourth side portion 18E4 of the base member 18.

[0045] Next, the positional relationship between the leaf spring 6, the shape memory alloy wire SA, the metal member 5, and the conductive member CM will be described with reference to Figs. 6A and 6B. Figs. 6A and 6B are diagrams showing the positional relationship between the leaf spring 6, the shape memory alloy wire SA, the metal member 5, and the conductive member CM. Specifically, Fig. 6A is a perspective view of each member (leaf spring 6, shape memory alloy wire SA, metal member 5, and conductive member CM), and Fig. 6B is a top view of each member. Note that in Fig. 6B, the shape memory alloy wire SA and the conductive member CM are omitted for clarity. Also, in Fig. 6B, a dot pattern is applied to the leaf spring 6.

[0046] As shown in Fig. 6B, the leaf spring 6 includes a first leaf spring 6A and a second leaf spring 6B. The first leaf spring 6A has a first portion 6A1 fixed to a first fixed-side pedestal portion 18D1 (see Fig. 2) of the base member 18, a second portion 6A2 fixed to a second fixed-side pedestal portion 18D2 (see Fig. 2) of the base member 18, a third portion 6A3 fixed to a first movable-side pedestal portion 2D1 (see Fig. 2) of the lens holding member 2, a fourth portion 6A4 connecting the first portion 6A1 and the third portion 6A3, and a fifth portion 6A5 connecting the second portion 6A2 and the third portion 6A3.

[0047] The first portion 6A1 is formed with a first through hole 6AH1 and a second through hole 6AH2, through which a round protruding portion 18T (see FIG. 3B) formed on the first fixed side base portion 18D1 and protruding upward is inserted. In this embodiment, the leaf spring 6 and the protruding portion 18T are fixed to each other by hot crimping or cold crimping the protruding portion 18T. However, the leaf spring 6 and the protruding portion 18T may also be fixed to each other by an adhesive.

[0048] The second portion 6A2 is formed with a third through hole 6AH3 through which a round protruding portion 18T (see FIG. 3B) formed on the second fixed side pedestal portion 18D2 protruding upward is inserted, and a fourth through hole 6AH4 used for joining the tenth joining surface portion CP10 (see FIG. 5C) of the tenth conductive member CM10. In this embodiment, the leaf spring 6 and the conductive member CM are joined by welding such as laser welding. However, the leaf spring 6 and the conductive member CM may also be joined by solder, a conductive adhesive, or the like.

[0049] The third portion 6A3 is formed with a fifth through hole 6AH5 and a sixth through hole 6AH6, through which a round protruding portion 2T (see FIG. 3A) formed on the first movable-side pedestal portion 2D1 protruding upward is inserted. In this embodiment, the leaf spring 6 and the protruding portion 2T are fixed by hot crimping or cold crimping the protruding portion 2T. However, the leaf spring 6 and the protruding portion 2T may also be fixed with an adhesive.

[0050] Similarly, the second leaf spring 6B has a first portion 6B1 fixed to the first fixed side base portion 18D1 (see Figure 2) of the base member 18, a second portion 6B2 fixed to the second fixed side base portion 18D2 (see Figure 2) of the base member 18, a third portion 6B3 fixed to the second movable side base portion 2D2 (see Figure 2) of the lens holding member 2, a fourth portion 6B4 connecting the first portion 6B1 and the third portion 6B3, and a fifth portion 6B5 connecting the second portion 6B2 and the third portion 6B3.

[0051] The first portion 6B1 is formed with a first through hole 6BH1 through which a round protrusion 18T (see Figure 3B) formed on the first fixed side base portion 18D1 protruding upward is inserted, and a second through hole 6BH2 used for joining to the ninth joining surface portion CP9 (see Figure 5C) of the ninth conductive member CM9.

[0052] The second portion 6B2 is formed with a third through hole 6BH3 and a fourth through hole 6BH4, into which a round protruding portion 18T (see FIG. 3B) formed on the second fixed side pedestal portion 18D2 and protruding upward is inserted.

[0053] The third portion 6B3 is formed with a fifth through hole 6BH5 and a sixth through hole 6BH6, into which a round protruding portion 2T (see FIG. 3A) formed on the second movable-side pedestal portion 2D2 and protruding upward is inserted.

[0054] The fourth portion 6A4 and the fifth portion 6A5 of the first leaf spring 6A and the fourth portion 6B4 and the fifth portion 6B5 of the second leaf spring 6B are elastically deformable arms having a plurality of bent portions. Therefore, the lens holding member 2 is movable with respect to the base member 18 (fixed member RG) not only in a direction parallel to the optical axis JD but also in a direction intersecting the optical axis JD.

[0055] As shown in FIG. 6B, the first leaf spring 6A and the second leaf spring 6B have substantially the same shape. Specifically, the first leaf spring 6A and the second leaf spring 6B are configured to have two-fold rotational symmetry (rotational symmetry with a minimum rotation angle of 180°) with respect to the optical axis JD. Therefore, this configuration can reduce the number of parts of the lens driving device 101. In addition, the first leaf spring 6A and the second leaf spring 6B can support the lens holding member 2 in the air in a well-balanced manner. In addition, the leaf spring 6 does not adversely affect the weight balance of the movable member MB supported by eight shape memory alloy wires SA (first wire SA1 to eighth wire SA8).

[0056] As shown in Fig. 6A, the first connection portion ED1 of the first conductive member CM1 is joined vertically to the connection portion CT1 of the first fixed side terminal plate 5F1 by soldering. That is, the first connection portion ED1 and the connection portion CT1 are joined in a state in which their surfaces are substantially vertical to each other. Similarly, the second connection portion ED2 of the second conductive member CM2 is joined vertically to the connection portion CT2 of the second fixed side terminal plate 5F2 by soldering, the third connection portion ED3 of the third conductive member CM3 is joined vertically to the connection portion CT3 of the third fixed side terminal plate 5F3 by soldering, and the fourth connection portion ED4 of the fourth conductive member CM4 is joined vertically to the connection portion CT4 of the fourth fixed side terminal plate 5F4 by soldering. In addition, the fifth connection portion ED5 of the fifth conductive member CM5 is vertically joined by soldering to the connection portion CT5 of the fifth fixed side terminal plate 5F5, the sixth connection portion ED6 of the sixth conductive member CM6 is vertically joined by soldering to the connection portion CT6 of the sixth fixed side terminal plate 5F6, the seventh connection portion ED7 of the seventh conductive member CM7 is vertically joined by soldering to the connection portion CT7 of the seventh fixed side terminal plate 5F7, and the eighth connection portion ED8 of the eighth conductive member CM8 is vertically joined by soldering to the connection portion CT8 of the eighth fixed side terminal plate 5F8.

[0057] As shown in FIG. 6B, the connection portion CT9 of the first movable terminal plate 5M1 is vertically joined to the third portion 6A3 of the first leaf spring 6A by soldering. That is, the connection portion CT9 and the third portion 6A3 are joined in a state in which their surfaces are substantially vertical to each other. Similarly, the connection portion CT10 of the second movable terminal plate 5M2 is vertically joined to the third portion 6A3 of the first leaf spring 6A by soldering, the connection portion CT11 of the third movable terminal plate 5M3 is vertically joined to the third portion 6B3 of the second leaf spring 6B by soldering, and the connection portion CT12 of the fourth movable terminal plate 5M4 is vertically joined to the third portion 6B3 of the second leaf spring 6B by soldering.

[0058] On the other hand, as shown in Fig. 6B, the first fixed side terminal plate 5F1 is disposed away from the first portion 6A1 of the first leaf spring 6A and is not in contact with the first portion 6A1 of the first leaf spring 6A. Similarly, the third fixed side terminal plate 5F3 is not in contact with the second portion 6A2 of the first leaf spring 6A, the fifth fixed side terminal plate 5F5 is not in contact with the first portion 6B1 of the second leaf spring 6B, and the seventh fixed side terminal plate 5F7 is not in contact with the second portion 6B2 of the second leaf spring 6B.

[0059] The ninth joint surface portion CP9 (see FIG. 5B) of the ninth conductive member CM9 is joined in parallel to the first portion 6B1 of the second leaf spring 6B by welding such as laser welding at the second through hole 6BH2 formed in the first portion 6B1 of the second leaf spring 6B. That is, the ninth joint surface portion CP9 and the first portion 6B1 are joined in a state in which their surfaces are substantially parallel to each other. Similarly, the tenth joint surface portion CP10 (see FIG. 5B) of the tenth conductive member CM10 is joined in parallel to the second portion 6A2 of the first leaf spring 6A by welding such as laser welding at the fourth through hole 6AH4 formed in the second portion 6A2 of the first leaf spring 6A.

[0060] Next, referring to Figures 7A and 7B, the path of the current flowing through the shape memory alloy wire SA will be described. Figures 7A and 7B are perspective views of a portion of the configuration shown in Figures 6A and 6B. In Figure 7A, for clarity, the first conductive member CM1 and the tenth conductive member CM10 are given a coarse dot pattern, the first leaf spring 6A is given a fine dot pattern, and the first movable side terminal plate 5M1 and the first fixed side terminal plate 5F1 are given an even finer dot pattern. Similarly, in Figure 7B, for clarity, the second conductive member CM2 and the tenth conductive member CM10 are given a coarse dot pattern, the first leaf spring 6A is given a fine dot pattern, and the first movable side terminal plate 5M1 and the second fixed side terminal plate 5F2 are given an even finer dot pattern.

[0061] 7A shows a current path when the first terminal TM1 of the first conductive member CM1 is connected to a high potential and the tenth terminal TM10 of the tenth conductive member CM10 is connected to a low potential, and Fig. 7B shows a current path when the second terminal TM2 of the second conductive member CM2 is connected to a high potential and the tenth terminal TM10 of the tenth conductive member CM10 is connected to a low potential. The following description relates to the current path flowing through the first wire SA1 or the second wire SA2, but may be similarly applied to the current path flowing through the third wire SA3 or the fourth wire SA4, the current path flowing through the fifth wire SA5 or the sixth wire SA6, and the current path flowing through the seventh wire SA7 or the eighth wire SA8.

[0062] When the first terminal TM1 of the first conductive member CM1 is connected to a high potential and the tenth terminal TM10 of the tenth conductive member CM10 is connected to a low potential, a current flows from the first terminal TM1 through the first conductive member CM1 to the first fixed terminal plate 5F1 as shown by the arrow AR1 in Fig. 7A. The current then flows through the first fixed terminal plate 5F1 as shown by the arrow AR2, the first wire SA1 as shown by the arrow AR3, and the first movable terminal plate 5M1 as shown by the arrow AR4. The current then flows through the third portion 6A3, the fifth portion 6A5, and the second portion 6A2 of the first leaf spring 6A as shown by the arrows AR5 and AR6, and then flows through the tenth conductive member CM10 to the tenth terminal TM10 as shown by the arrow AR7.

[0063] When the second terminal TM2 of the second conductive member CM2 is connected to a high potential and the tenth terminal TM10 of the tenth conductive member CM10 is connected to a low potential, a current flows from the second terminal TM2 through the second conductive member CM2 to the second fixed terminal plate 5F2 as shown by an arrow AR11 in FIG. 7B. The current then flows through the second fixed terminal plate 5F2 as shown by an arrow AR12, the second wire SA2 as shown by an arrow AR13, and the first movable terminal plate 5M1 as shown by an arrow AR14. The current then flows through the third portion 6A3, the fifth portion 6A5, and the second portion 6A2 of the first leaf spring 6A as shown by an arrow AR15 and an arrow AR16, and then flows through the tenth conductive member CM10 to the tenth terminal TM10 as shown by an arrow AR17.

[0064] Whether the first terminal portion TM1 of the first conductive member CM1 is connected to a high potential or the second terminal portion TM2 of the second conductive member CM2 is connected to a high potential, the path of the current flowing from the first movable side terminal plate 5M1 to the tenth terminal portion TM10 is the same.

[0065] The control device external to the lens driving device 101 as described above can control the contraction of each of the first wire SA1 to the eighth wire SA8 by controlling the voltages applied to the terminal portions of the first conductive member CM1 to the tenth conductive member CM10. The control device may be disposed inside the lens driving device 101. The control device may also be a component of the lens driving device 101.

[0066] Lens driving device 101 having a substantially rectangular parallelepiped shape is attached, for example, on an external board (not shown) on which an imaging element (not shown) is mounted. The camera module is composed of, for example, the external board, lens driving device 101, a lens body attached to lens holding member 2, and an imaging element mounted on the external board so as to face the lens body. The camera module may include a control device.

[0067] The control device may use, for example, a driving force along a direction parallel to the optical axis JD caused by contraction of a shape memory alloy wire SA as a driving mechanism MK to move the lens holding member 2 along a direction parallel to the optical axis JD on the Z1 side (subject side) of the imaging element. By moving the lens holding member 2 in this manner, the control device may realize an automatic focus adjustment function, which is one of the lens adjustment functions. Specifically, the control device may move the lens holding member 2 in a direction away from the imaging element to enable macro photography, and move the lens holding member 2 in a direction approaching the imaging element to enable infinity photography.

[0068] The control device may also control the current flowing through the shape memory alloy wires SA to move the lens holding member 2 in a direction intersecting the optical axis JD. In this way, the control device may achieve a camera shake correction function.

[0069] Next, with reference to Figs. 8A and 8B, and Figs. 9A and 9B, an example of a connection structure for connecting the fixed metal member 5F (fixed side terminal plate) and the conductive member CM will be described. Figs. 8A and 8B, and Figs. 9A and 9B are diagrams showing an example of a connection structure for connecting the fixed metal member 5F (fixed side terminal plate) and the conductive member CM. Specifically, Fig. 8A is an overall perspective view of the base member 18 to which the fixed metal member 5F (fixed side terminal plate) is attached. Fig. 8B is an enlarged side view of the range R1 surrounded by the dashed line shown in Fig. 8A when viewed from the Y1 side. Fig. 9A is an enlarged bottom view of the range R2 surrounded by the dashed line shown in Fig. 8B when viewed from the Z2 side. Fig. 9B is a view of the connection part CT1 of the first fixed side terminal plate 5F1 and the first connection part ED1 of the first conductive member CM1 when viewed from the front side (X1 side). In addition, in Figures 8A and 8b, and Figures 9A and 9B, for clarity, a coarse dot pattern is applied to the fixed side metal member 5F (fixed side terminal plate) and a fine dot pattern is applied to the conductive member CM.

[0070] As shown in Figures 8B and 9A, the first fixed side terminal plate 5F1 is attached to the Y1 side wall (right mounting surface) of the first fixed side pedestal portion 18D1 of the base member 18 with a photocurable adhesive. The connection portion CT1 of the first fixed side terminal plate 5F1 is joined to the first connection portion ED1 of the first conductive member CM1 via a bonding material SD. The bonding material SD is, for example, solder or a conductive adhesive. Note that in Figures 8B, 9A, and 9B, a cross pattern is applied to the bonding material SD for clarity.

[0071] Similarly, the second fixed side terminal plate 5F2 is attached by a light-curing adhesive to the Y1 side wall (right-side mounting surface) of the first fixed side pedestal portion 18D1 of the base member 18. The connection portion CT2 of the second fixed side terminal plate 5F2 is joined to the second connection portion ED2 of the second conductive member CM2 via the bonding material SD.

[0072] As shown in Figures 9A and 9B, the connection part CT1 is disposed so as to cover at least a part of the end face EP on the Y1 side (right side) of the first connection part ED1. Specifically, as shown in Figure 9B, the first fixed side terminal plate 5F1 is bent outward (toward the Y1 side) at the base RT of the connection part CT1 so that the connection part CT1 is located outside (toward the Y1 side) of the first connection part ED1. The same is true for the connection part CT2.

[0073] This arrangement allows the bonding material SD to adhere to at least the lower surface (surface on the Z2 side) of the connection portion CT1 and the outer surface (Y1 side) of the first connection portion ED1, thereby increasing the connection strength between the connection portion CT1 and the first connection portion ED1 by the bonding material SD. Typically, this arrangement allows the bonding material SD to adhere to multiple surfaces constituting the first connection portion ED1 and multiple surfaces constituting the connection portion CT1, thereby increasing the connection strength between the connection portion CT1 and the first connection portion ED1 by the bonding material SD. The same applies to the connection strength between the connection portion CT2 and the second connection portion ED2 by the bonding material SD.

[0074] 9A, a recess RS1 is formed at the tip of the first connection part ED1. This configuration allows the bonding material SD to easily enter between the connection part CT1 and the first connection part ED1, thereby increasing the connection strength between the connection part CT1 and the first connection part ED1 by the bonding material SD. The same applies to the connection strength between the connection part CT2 and the second connection part ED2, which has a recess RS2 formed at its tip, by the bonding material SD.

[0075] This arrangement also prevents the connection part CT1 from being joined to only the end face EP (Y1 side face) of the first connection part ED1, which is not plated, by the joining material SD. The same applies to the joining between the second connection part ED2 and the connection part CT2.

[0076] Next, a configuration for restricting the movement of the lens holding member 2 relative to the base member 18 when the shape memory alloy wire SA is not energized will be described with reference to Fig. 10. Fig. 10 is a perspective view of the lens holding member 2, the upper cover member 4U, and the base member 18.

[0077] As shown in Figure 10, the lens holding member 2 has a cylindrical portion 12 that extends in the optical axis direction and houses the lens body therein, and a movable side base portion 2D and a protruding portion 2S that protrude from the cylindrical portion 12 toward the corner 4E at a position corresponding to the corner 4E of the upper cover member 4U.

[0078] Specifically, the upper cover member 4U has four corners 4E. The four corners 4E include a first corner 4E1 disposed between the first side plate portion 4A1 and the fourth side plate portion 4A4, a second corner 4E2 disposed between the first side plate portion 4A1 and the second side plate portion 4A2, a third corner 4E3 disposed between the second side plate portion 4A2 and the third side plate portion 4A3, and a fourth corner 4E4 disposed between the third side plate portion 4A3 and the fourth side plate portion 4A4.

[0079] The lens holding member 2 has a second movable side base portion 2D2 protruding from the cylindrical portion 12 toward the first corner portion 4E1, a first protrusion portion 2S1 protruding from the cylindrical portion 12 toward the second corner portion 4E2, the first movable side base portion 2D1 protruding from the cylindrical portion 12 toward the third corner portion 4E3, and a second protrusion portion 2S2 protruding from the cylindrical portion 12 toward the fourth corner portion 4E4.

[0080] The protruding portion 2S is formed with a housing portion HR that opens upward (Z1 direction). The first magnetic member 10 is housed in the housing portion HR and fixed thereto by adhesive. Specifically, the first protruding portion 2S1 is formed with a first housing portion HR1 that opens upward, and the second protruding portion 2S2 is formed with a second housing portion HR2 that opens upward. The first housing portion HR1 houses a first magnet 10A, and the second housing portion HR2 houses a second magnet 10B.

[0081] The first magnetic member 10 is a member for generating a magnetic attraction force between itself and the second magnetic member MG (see FIGS. 12A and 12B) attached to the base member 18. In the example shown in FIG. 10, the first magnetic member 10 includes a first magnet 10A and a second magnet 10B. Both the first magnet 10A and the second magnet 10B are two-pole permanent magnets. However, the first magnetic member 10 does not have to be a magnet as long as it can generate a magnetic attraction force between itself and the second magnetic member MG. In this case, the first magnetic member 10 may be, for example, a magnetic metal or a magnetic resin material. In addition, the first magnetic member 10 may be embedded in the lens holding member 2 by insert molding or the like, or may be attached to the lens holding member 2.

[0082] The base member 18 has a fixed side pedestal portion 18D and a stopper protrusion portion 18S that protrude upward at a position corresponding to the corner portion 4E of the upper cover member 4U. The stopper protrusion portion 18S includes a first stopper protrusion portion 18S1 and a second stopper protrusion portion 18S2. Specifically, the base member 18 has a second stopper protrusion portion 18S2 provided in the vicinity of the first corner portion 4E1, a first fixed side pedestal portion 18D1 provided in the vicinity of the second corner portion 4E2, the first stopper protrusion portion 18S1 provided in the vicinity of the third corner portion 4E3, and a second fixed side pedestal portion 18D2 provided in the vicinity of the fourth corner portion 4E4.

[0083] The fixed side pedestal portion 18D is formed with a stopper recess SB that opens upward (Z1 direction) and inward (direction approaching the optical axis JD). Specifically, the first fixed side pedestal portion 18D1 is formed with a first stopper recess SB1 that opens upward and inward, and the second fixed side pedestal portion 18D2 is formed with a second stopper recess SB2 that opens upward and inward. The stopper recess SB accommodates the protruding portion 2S that functions as a stopper protrusion.

[0084] As shown in Figs. 11A to 11C, the lens holding member 2 has a stopper recess CV formed on the lower surface (Z2 side surface) of the movable base portion 2D. Figs. 11A to 11C are detailed views of the lens holding member 2. Specifically, Fig. 11A is a bottom view of the lens holding member 2. Fig. 11B is a bottom perspective view of the lens holding member 2. Fig. 11C is an enlarged view of an area R3 surrounded by a dashed line shown in Fig. 11B. Note that in Figs. 11A to 11C, a dot pattern is applied to the stopper recess CV for clarity.

[0085] Specifically, a first stopper recess CV1 is formed on the lower surface of the first movable-side pedestal portion 2D1, and a second stopper recess CV2 is formed on the lower surface of the second movable-side pedestal portion 2D2.

[0086] As described above, the stopper recess CV has the first stopper recess CV1 and the second stopper recess CV2. The stopper recess CV is configured to receive the stopper protrusion 18S (see FIG. 10) formed on the base member 18 in a non-contact manner. The stopper protrusion 18S includes the first stopper protrusion 18S1 and the second stopper protrusion 18S2 as described above.

[0087] The stopper recess CV is configured to cooperate with the stopper protrusion 18S to limit excessive movement of the lens holding member 2. Specifically, the stopper recess CV is configured to come into contact with the stopper protrusion 18S when the movement of the lens holding member 2 becomes excessively large, thereby limiting the excessive movement of the lens holding member 2. The excessive movement of the lens holding member 2 includes at least one of excessive rotation about the optical axis JD of the lens holding member 2, excessive translation of the lens holding member 2 in the X-axis direction, and excessive translation of the lens holding member 2 in the Y-axis direction.

[0088] More specifically, the first stopper recess CV1 is configured to receive the first stopper protrusion 18S1 in a non-contact manner in the initial state, and the second stopper recess CV2 is configured to receive the second stopper protrusion 18S2 in a non-contact manner in the initial state. The initial state of the lens driving device 101 means, for example, the state of the lens driving device 101 when the shape memory alloy wire SA is not energized.

[0089] Moreover, the stopper recess SB of the base member 18 is configured to receive the protrusion 2S (stopper protrusion) of the lens holding member 2 in a non-contact manner in the initial state. The stopper recess SB is configured to cooperate with the stopper protrusion (protrusion 2S) to limit excessive movement of the lens holding member 2. Specifically, the stopper recess SB is configured to come into contact with the stopper protrusion (protrusion 2S) to limit excessive movement of the lens holding member 2 when the movement of the lens holding member 2 becomes excessively large.

[0090] More specifically, the stopper recess SB includes a first stopper recess SB1 formed on the inside of the first fixed-side pedestal portion 18D1 and a second stopper recess SB2 formed on the inside of the second fixed-side pedestal portion 18D2. The first stopper recess SB1 is configured to receive the first stopper convex portion (first protruding portion 2S1) in a non-contact manner in the initial state, and the second stopper recess SB2 is configured to receive the second stopper convex portion (second protruding portion 2S2) in a non-contact manner in the initial state.

[0091] In this way, the stopper recess CV (movable side base portion 2D) and the stopper protrusion (protrusion portion 2S) in the lens holding member 2, as well as the stopper recess SB (fixed side base portion 18D) and the stopper protrusion 18S in the base member 18, form a stopper portion ST that limits excessive movement of the lens holding member 2.

[0092] Specifically, the stopper portion ST includes a first stopper portion ST1 to a fourth stopper portion ST4, as shown in Fig. 10. The first stopper portion ST1 is formed by a combination of the first protruding portion 2S1 and the first fixed side pedestal portion 18D1, the second stopper portion ST2 is formed by a combination of the second protruding portion 2S2 and the second fixed side pedestal portion 18D2, the third stopper portion ST3 is formed by a combination of the first movable side pedestal portion 2D1 and the first stopper convex portion 18S1, and the fourth stopper portion ST4 is formed by a combination of the second movable side pedestal portion 2D2 and the second stopper convex portion 18S2.

[0093] 11A to 11C, the movable-side pedestal portion 2D of the lens holding member 2 has a mounting surface EW to which the movable-side metal member 5M is attached. Specifically, the first mounting surface EW1 (right mounting surface) to which the first movable-side terminal plate 5M1 is attached is formed on the Y1-side side wall of the first movable-side pedestal portion 2D1, and the second mounting surface EW2 (rear mounting surface) to which the second movable-side terminal plate 5M2 is attached is formed on the X2-side side wall of the first movable-side pedestal portion 2D1. The third mounting surface EW3 (front mounting surface) to which the third movable-side terminal plate 5M3 is attached is formed on the X1-side side wall of the second movable-side pedestal portion 2D2, and the fourth mounting surface EW4 (left mounting surface) to which the fourth movable-side terminal plate 5M4 is attached is formed on the Y2-side side wall of the second movable-side pedestal portion 2D2.

[0094] Next, referring to Fig. 12A and Fig. 12B, the positional relationship between the first magnetic member 10 and the second magnetic member MG when the shape memory alloy wire SA is not energized will be described. Fig. 12A and Fig. 12B show the positional relationship between the first magnetic member 10 attached to the lens holding member 2 and the second magnetic member MG included in the conductive member CM embedded in the base member 18 when the shape memory alloy wire SA is not energized. Specifically, Fig. 12A is a perspective view of the first magnetic member 10 and the conductive member CM, and Fig. 12B is a top view of the conductive member CM. Note that in Fig. 12A and Fig. 12B, for clarity, members other than the first magnetic member 10 and the conductive member CM are omitted. In Fig. 12A and Fig. 12B, for clarity, a dot pattern is applied to the second magnetic member MG, which is a part of the conductive member CM embedded in the base member 18. In Fig. 12B, for clarity, the outline of the first magnetic member 10 is shown by a dotted line.

[0095] The second magnetic member MG is a member for generating a magnetic attraction force between itself and the first magnetic member 10 attached to the lens holding member 2. In the example shown in FIG. 12A and FIG. 12B, the second magnetic member MG includes a first metal plate MG1 and a second metal plate MG2. The first metal plate MG1 and the second metal plate MG2 are both formed of a magnetic metal. Specifically, the first metal plate MG1 is formed as a part of the second conductive member CM2, and the second metal plate MG2 is formed as a part of the eighth conductive member CM8. However, the second magnetic member MG does not have to be a magnetic metal as long as it can generate a magnetic attraction force between itself and the first magnetic member 10. In this case, the second magnetic member MG may be a magnet. The second magnetic member MG may be configured as a member independent of the conductive member CM. In this case, the conductive member CM is preferably formed of a non-magnetic material such as a non-magnetic metal. The second magnetic member MG does not have to be embedded in the base member 18, and may be attached to the base member 18.

[0096] When no current is applied to the shape memory alloy wire SA, as shown in Figures 12A and 12B, the first magnetic member 10 is positioned in the accommodating portion HR formed in the protruding portion 2S of the lens holding member 2 so as to be located directly above the second magnetic member MG, a predetermined distance away from the second magnetic member MG.

[0097] 12B, the first magnetic member 10 and the second magnetic member MG are configured such that the area of ​​the upper opposing surface CSU of the first magnetic member 10 facing the second magnetic member MG is approximately equal to the area of ​​the lower opposing surface CSL of the second magnetic member MG facing the first magnetic member 10. If the area of ​​the upper opposing surface CSU and the area of ​​the lower opposing surface CSL are significantly different, the positional relationship between the first magnetic member 10 and the second magnetic member MG will vary when the first magnetic member 10 is attracted to the second magnetic member MG by the magnetic attraction force generated between the first magnetic member 10 and the second magnetic member MG and comes to rest.

[0098] 12B, the first magnet 10A and the first metal plate MG1 are configured so that the area of ​​the upper facing surface CSU1 of the first magnet 10A facing the first metal plate MG1 is approximately equal to the area of ​​the lower facing surface CSL1 of the first metal plate MG1 facing the first magnet 10A. Also, the second magnet 10B and the second metal plate MG2 are configured so that the area of ​​the upper facing surface CSU2 of the second magnet 10B facing the second metal plate MG2 is approximately equal to the area of ​​the lower facing surface CSL2 of the second metal plate MG2 facing the second magnet 10B.

[0099] 12A and 12B, the first magnetic member 10 has a substantially rectangular parallelepiped outer shape, but may have other outer shapes, such as a cylinder or a hexagonal prism. That is, in the example shown in Fig. 12A and 12B, the upper facing surface CSU has a rectangular outer shape, but may have other outer shapes, such as a circle or a hexagon. In this case, the lower facing surface CSL is preferably configured to have the same outer shape as the upper facing surface CSU.

[0100] Next, the stopper portion ST that restricts the movement of the lens holding member 2 will be described in detail with reference to Fig. 13A and Fig. 13B. Here, the first stopper portion ST1 and the second stopper portion ST2 will be particularly described. Fig. 13A and Fig. 13B are top views of the lens holding member 2 to which the first magnetic member 10 is attached, and the base member 18 in which the second magnetic member MG is embedded. Specifically, Fig. 13A is a top view of the entire lens holding member 2 and the base member 18, and Fig. 13B is an enlarged view of the range R4 surrounded by the dashed line shown in Fig. 13A.

[0101] As described above, the first stopper portion ST1 is formed by a combination of the first protrusion portion 2S1 and the first fixed side base portion 18D1, and the second stopper portion ST2 is formed by a combination of the second protrusion portion 2S2 and the second fixed side base portion 18D2.

[0102] Specifically, as shown in FIG. 13B, the second stopper portion ST2 is configured by a combination of a second protruding portion 2S2 having an outer peripheral surface CF (surface indicated by a dotted line) and a second fixed-side pedestal portion 18D2 (a recessed portion SB2 for a second stopper) as a wall portion having an inner peripheral surface SF (surface indicated by a broken line) that faces the outer peripheral surface CF so as to cover the outer peripheral surface CF. The outer peripheral surface CF and the inner peripheral surface SF face each other at a predetermined interval, and are disposed so as to be closest to each other at a portion extending parallel to the X-axis and a portion extending parallel to the Y-axis. Similarly, as shown in FIG. 13A, the first stopper portion ST1 is configured by a combination of a first protruding portion 2S1 having an outer peripheral surface and a first fixed-side pedestal portion 18D1 (a recessed portion SB1 for a first stopper) as a wall portion having an inner peripheral surface that faces the outer peripheral surface so as to cover the outer peripheral surface.

[0103] With this configuration, when the lens holding member 2 tries to rotate excessively around the optical axis JD in the direction indicated by the arrow AR20 in Fig. 13A, the right portion CFR of the outer peripheral surface CF of the second protruding portion 2S2 comes into contact with the right portion SFR of the inner peripheral surface SF of the second fixed-side base portion 18D2 (second stopper recess SB2) at the second stopper portion ST2, as shown in Fig. 13B. As a result, the excessive rotation of the lens holding member 2 around the optical axis JD is prevented by this contact. The same is true for the first stopper portion ST1, and the contact at the first stopper portion ST1 and the contact at the second stopper portion ST2 occur at approximately the same timing.

[0104] Also, when the lens holding member 2 tries to rotate excessively around the optical axis JD in the direction indicated by the arrow AR21 in Fig. 13A, the left portion CFL of the outer peripheral surface CF of the second protruding portion 2S2 comes into contact with the left portion SFL of the inner peripheral surface SF of the second fixed-side pedestal portion 18D2 (second stopper recess SB2) at the second stopper portion ST2, as shown in Fig. 13B. As a result, the excessive rotation of the lens holding member 2 around the optical axis JD is prevented by this contact. The same is true for the first stopper portion ST1, and the contact at the first stopper portion ST1 and the contact at the second stopper portion ST2 occur at approximately the same timing.

[0105] Next, the interval between the first magnetic member 10 and the second magnetic member MG in the optical axis direction will be described with reference to Figures 14A and 14B. Figures 14A and 14B show cross sections of the lens holding member 2, the first magnetic member 10, the base member 18, and the second magnetic member MG in a plane perpendicular to the XY plane, including the dashed line L1 in Figure 13A. Specifically, Figure 14A shows an example of the positional relationship between the first magnetic member 10 and the second magnetic member MG before the current is started to be passed through the shape memory alloy wire SA, and Figure 14B shows an example of the positional relationship between the first magnetic member 10 and the second magnetic member MG after the current is started to be passed through the shape memory alloy wire SA.

[0106] As shown in FIG. 14A, before the current is applied to the shape memory alloy wire SA, the shape memory alloy wire SA is not contracted enough to lift the lens holding member 2. Also, the first magnetic member 10 housed in the housing portion HR of the lens holding member 2 is attracted to the second magnetic member MG embedded in the base member 18. Therefore, the bottom surface BF of the lens holding member 2 and the top surface TF of the base member 18 are in contact with each other so as to attract each other. Specifically, the lens holding member 2 is in contact with the base member 18 at four points (the bottom surfaces of the four corners). That is, unless a force (a force acting in a direction to pull the lens holding member 2 away from the base member 18) greater than the magnetic attraction force generated between the first magnetic member 10 and the second magnetic member MG acts on the lens holding member 2, the contact between the lens holding member 2 and the base member 18 is maintained, and the stationary state of the lens holding member 2 is also maintained.

[0107] Since the first magnetic member 10 is housed in the housing portion HR with its bottom surface in contact with the bottom portion BW of the housing portion HR, its position in the optical axis direction (Z-axis direction) is determined by the bottom portion BW.

[0108] In addition, the second magnetic member MG is embedded in the synthetic resin while being sandwiched in the mold by a pair of positioning pins during insert molding, and therefore its position in the optical axis direction (Z-axis direction) is determined by the positioning pins. The upper circular hole HL1 and the lower circular hole HL2 shown in Fig. 14A and Fig. 14B are holes formed by a pair of positioning pins. However, the upper circular hole HL1 and the lower circular hole HL2 may be omitted. This is because, in the example shown in Fig. 14A and Fig. 14B, the second magnetic member MG is a part of the conductive member CM, and the conductive member CM may be sandwiched in the mold by another positioning pin at a different position.

[0109] With this configuration, before the current is applied to the shape memory alloy wire SA, the first magnetic member 10 and the second magnetic member MG attract each other while being spaced apart by a predetermined distance. That is, the first magnetic member 10 and the second magnetic member MG are arranged at a distance from each other so that the magnetic attraction force does not become excessively large. Specifically, as shown in FIG. 14A, the first magnet 10A and the first metal plate MG1 attract each other while being spaced apart by a distance H1. That is, the first magnet 10A and the first metal plate MG1 are arranged at a distance from each other so that the magnetic attraction force does not become excessively large.

[0110] When the current is applied to the shape memory alloy wire SA, the shape memory alloy wire SA is heated by resistance heating and contracts in response to the rise in wire temperature due to the heating. When the shape memory alloy wire SA contracts, the lens holding member 2 is lifted by the contracted shape memory alloy wire SA and moves in the Z1 direction (upward) away from the base member 18 as shown in Fig. 14B. Fig. 14B shows a state in which the lens holding member 2 has moved in the Z1 direction until the distance between the bottom surface BF of the lens holding member 2 and the top surface TF of the base member 18 becomes a distance H2.

[0111] With the above-mentioned configuration, before the current is applied to the shape memory alloy wire SA, the position (height) of the lens holding member 2 in the Z-axis direction is determined by the upper surface TF of the base member 18. The rotational position (angular position) of the lens holding member 2 around the Z-axis is determined by the magnetic attraction force generated between the first magnetic member 10 and the second magnetic member MG. The magnetic attraction force generated between the first magnetic member 10 and the second magnetic member MG includes the magnetic attraction force generated between the first magnet 10A and the first metal plate MG1, and the magnetic attraction force generated between the second magnet 10B and the second metal plate MG2. The rotational deviation of the lens holding member 2 around the Z-axis is eliminated by the magnetic attraction force generated between the first magnetic member 10 and the second magnetic member MG. The positional deviation of the lens holding member 2 in the X-axis direction and the positional deviation of the lens holding member 2 in the Y-axis direction are also eliminated by the magnetic attraction force generated between the first magnetic member 10 and the second magnetic member MG. Therefore, before current is applied to the shape memory alloy wire SA, the lens holding member 2 is moved by the suction force so that its relative position to the base member 18 becomes a predetermined position, and after the predetermined position is reached, the lens holding member 2 is held by the suction force so that the relative position is maintained unless an external force greater than the suction force acts on the lens holding member 2.

[0112] As described above, the lens driving device 101 comprises a fixed side member RG including a base member 18 and a cover member 4, a lens holding member 2 that is arranged in a storage space formed by the base member 18 and the cover member 4 (upper cover member 4U) and is capable of holding a lens body, and a plurality of shape memory alloy wires SA that are arranged between the movable side member MB including the lens holding member 2 and the fixed side member RG.

[0113] The lens holding member 2 is disposed on the upper side of the base member 18, which is the subject side, and is configured to be movable by energizing the shape memory alloy wire SA. The lens holding member 2 may be configured to be movable, for example, in the optical axis direction and in a direction intersecting the optical axis direction. Alternatively, the lens holding member 2 may be configured to be movable only in the optical axis direction relative to the base member 18.

[0114] The lens holding member 2 has a plurality of first magnetic members 10 arranged at a plurality of different positions, and the base member 18 has a plurality of second magnetic members MG corresponding to the plurality of first magnetic members 10. The lens holding member 2 and the base member 18 are configured such that each of the plurality of first magnetic members 10 is attracted to the corresponding second magnetic member MG, and the movement of the lens holding member 2 is restricted by the base member 18 when the shape memory alloy wire SA is not energized. In other words, the lens holding member 2 is configured such that the relative position of the lens holding member 2 with respect to the base member 18 is maintained in a predetermined position by the attractive force generated between the first magnetic member 10 attached to the lens holding member 2 and the second magnetic member MG attached to the base member 18.

[0115] For example, as shown in Fig. 10, the lens holding member 2 has a first magnet 10A and a second magnet 10B disposed at two different positions as the multiple first magnetic members 10, and the base member 18 has a first metal plate MG1 corresponding to the first magnet 10A and a second metal plate MG2 corresponding to the second magnet 10B embedded therein as multiple second magnetic members MG corresponding to the multiple first magnetic members 10 as shown in Fig. 12A and Fig. 12B. In this configuration, the lens holding member 2 has the first magnet 10A magnetically attracted to the first metal plate MG1 and the second magnet 10B magnetically attracted to the second metal plate MG2, so that the movement of the lens holding member 2 is restricted when the shape memory alloy wire SA is not energized. That is, the lens holding member 2 is configured so that its relative posture with respect to the base member 18 is a predetermined posture (for example, the posture shown in FIG. 13A) due to the attractive force generated between a first magnet 10A attached to the lens holding member 2 and a first metal plate MG1 embedded in the base member 18, and the attractive force generated between a second magnet 10B attached to the lens holding member 2 and a second metal plate MG2 embedded in the base member 18.

[0116] 10, two first magnetic members 10 are attached to the lens holding member 2, but three or more first magnetic members 10 may be attached to the lens holding member 2. In this case, the same number of second magnetic members MG as the number of first magnetic members 10 are embedded in the base member 18.

[0117] With the above-mentioned configuration, the lens driving device 101 can prevent undesired movement of the lens holding member 2 in the initial state when the shape memory alloy wire SA is not energized. Therefore, the lens driving device 101 can prevent the occurrence of undesirable situations such as the center of the lens body being misaligned from the center of the camera module in the initial state.

[0118] Furthermore, in the initial state, the lens driving device 101 can suppress the generation of noise caused by repeated contact and non-contact between the lens holding member 2 and the base member 18. This is because the contact state between the lens holding member 2 and the base member 18 is maintained by the attractive force between the first magnetic member 10 and the second magnetic member MG. Note that, when no attractive force is acting, repeated contact and non-contact between the lens holding member 2 and the base member 18 is caused by vibrations of a vibrator provided near the lens driving device 101, vibrations of a speaker provided near the lens driving device 101, or vibrations of the lens driving device 101 when a user shakes a portable device in which the lens driving device 101 is incorporated.

[0119] Furthermore, in the above-described configuration, the movement of the lens holding member 2 is restricted at at least two points (two first magnetic members 10 and two second magnetic members MG), so the movement of the lens holding member 2 can be restricted more reliably than in a configuration in which the movement of the lens holding member 2 is restricted at only one point. This is because in a configuration in which the movement of the lens holding member 2 is restricted at only one point, there is a risk that the lens holding member 2 will rotate around the first magnetic member. Preferably, the two first magnetic members 10 are arranged on opposite sides of the optical axis JD.

[0120] The upper surface of the second magnetic member MG may be covered with the synthetic resin forming the base member 18. In this case, the upper surface of the second magnetic member MG may be partially covered with the synthetic resin. The base member 18 and the lens holding member 2 may be configured to contact each other when the shape memory alloy wire SA is not energized. Specifically, the first metal plate MG1 as the second magnetic member MG may be embedded in the base member 18 as shown in FIG. 14A. The base member 18 and the lens holding member 2 may be configured to contact each other when the shape memory alloy wire SA is not energized, and the distance between the first magnet 10A and the first metal plate MG1 is a distance H1.

[0121] This configuration can maintain the closest distance (hereinafter, "minimum approach distance") between the first magnetic member 10 and the second magnetic member MG at a predetermined distance H1 (see FIG. 14A) or more, and therefore can prevent the magnetic attraction force generated between the first magnetic member 10 and the second magnetic member MG from becoming excessively strong. Therefore, this configuration can prevent the movement of the lens holding member 2 (movement against the attraction force) from becoming excessively slow when electricity is applied to the shape memory alloy wire SA. That is, this configuration can speed up the movement of the lens holding member 2 when electricity is applied to the shape memory alloy wire SA, compared to a configuration in which the second magnetic member MG is exposed on the surface of the base member 18 and the second magnetic member MG and the lens holding member 2 are in contact with each other (a configuration in which the minimum approach distance is smaller).

[0122] The first magnetic member 10 is preferably a magnet. In the example shown in Fig. 10, the first magnetic member 10 includes a first magnet 10A and a second magnet 10B as two-pole permanent magnets polarized along the optical axis direction. In this case, as the second magnetic member MG, preferably, metal plates (first metal plate MG1 and second metal plate MG2) are used instead of magnets, as in the example shown in Fig. 12A and Fig. 12B.

[0123] However, a magnet may be used as the second magnetic member MG, and a metal plate may be used as the first magnetic member 10. Alternatively, a magnet may be used as the first magnetic member 10, and a magnet may be used as the second magnetic member MG.

[0124] 12B, the first magnetic member 10 and the second magnetic member MG are preferably configured so that the area of ​​the upper opposing surface CSU of the first magnetic member 10 facing the second magnetic member MG is equal to the area of ​​the lower opposing surface CSL of the second magnetic member MG facing the first magnetic member 10. This is to prevent the relative position of the lens holding member 2 with respect to the base member 18 from varying when the shape memory alloy wire SA is not energized.

[0125] As shown in Figs. 5A to 5C, a conductive member CM electrically connected to the shape memory alloy wire SA may be embedded in the base member 18. The second magnetic member MG may be made of the same metal as the conductive member CM as shown in Figs. 12A and 12B. In the example shown in Figs. 12A and 12B, the first metal plate MG1 as the second magnetic member MG is a part of the second conductive member CM2, and the second metal plate MG2 as the second magnetic member MG is a part of the eighth conductive member CM8. This configuration can improve the productivity of the lens driving device 101. This is because the conductive member CM and the second magnetic member MG are integrally formed.

[0126] As shown in Fig. 10, the upper cover member 4U preferably has a first outer peripheral wall portion 4A and a top plate portion 4B, and has a rectangular shape in a plan view seen from the optical axis direction. The first magnetic member 10 is provided at two locations on the lens holding member 2 corresponding to two corners 4E of the upper cover member 4U arranged diagonally. Specifically, in the example shown in Fig. 10, a first magnet 10A, which is an example of the first magnetic member 10, is attached to a first protruding portion 2S1 of the lens holding member 2 at a position corresponding to a second corner 4E2 of the upper cover member 4U, and a second magnet 10B, which is another example of the first magnetic member 10, is attached to a second protruding portion 2S2 of the lens holding member 2 at a position corresponding to a fourth corner 4E4 arranged on the opposite side of the second corner 4E2 across the optical axis JD.

[0127] This configuration allows the first magnetic member 10 to be disposed in a space that is likely to become a dead space near the inside of the corner 4E of the upper cover member 4U, and therefore makes it possible to prevent the lens driving device 101 from becoming large.

[0128] 10, the lens holding member 2 may have a cylindrical portion 12 that extends in the optical axis direction and accommodates the lens body therein, and a protruding portion 2S that protrudes from the cylindrical portion 12 toward the corner 4E at a position corresponding to the corner 4E of the upper cover member 4U. In this case, the protruding portion 2S is provided with a storage portion HR having a bottom portion BW (see FIG. 14A), and the storage portion HR accommodates the first magnetic member 10.

[0129] 10, the lens holding member 2 has a first protruding portion 2S1 protruding from the cylindrical portion 12 toward the second corner 4E2 at a position corresponding to the second corner 4E2 of the upper cover member 4U, and a second protruding portion 2S2 protruding from the cylindrical portion 12 toward the fourth corner 4E4 at a position corresponding to the fourth corner 4E4 of the upper cover member 4U. The first protruding portion 2S1 is provided with a first housing portion HR1 having a bottom BW (see FIG. 14A), and the first magnet 10A is housed in the first housing portion HR1. The second protruding portion 2S2 is provided with a second housing portion HR2 having a bottom, and the second magnet 10B is housed in the second housing portion HR2.

[0130] This configuration enables the first magnetic member 10 to be placed at a predetermined position, and prevents the first magnetic member 10 from becoming displaced.

[0131] 13B, the base member 18 may have a fixed-side pedestal portion 18D as a wall portion having an inner peripheral surface SF that faces and covers the outer peripheral surface CF of the protruding portion 2S. In this case, the protruding portion 2S and the fixed-side pedestal portion 18D may form a stopper portion ST that regulates the movement of the lens holding member 2 that attempts to rotate at least around the optical axis JD.

[0132] Specifically, in the example shown in Fig. 13B, the base member 18 has a second fixed-side pedestal portion 18D2 having an inner peripheral surface SF that faces and covers the outer peripheral surface CF of the second protruding portion 2S2. The second protruding portion 2S2 and the second fixed-side pedestal portion 18D2 form a second stopper portion ST2 that restricts excessive movement of the lens holding member 2 that attempts to rotate at least around the optical axis JD. The same is true for the stopper portion ST1 (see Fig. 13A) formed by the first protruding portion 2S1 and the first fixed-side pedestal portion 18D1.

[0133] In the example shown in FIG. 13A, the first stopper portion ST1 formed by the first protrusion portion 2S1 and the first fixed side base portion 18D1, and the second stopper portion ST2 formed by the second protrusion portion 2S2 and the second fixed side base portion 18D2 are configured to regulate not only excessive movement of the lens holding member 2 attempting to rotate around the optical axis JD (excessive rotation around the Z axis), but also excessive translation along the X axis direction, excessive translation along the Y axis direction, excessive translation in the Z2 direction, excessive rotation around the X axis, and excessive rotation around the Y axis.

[0134] In this configuration, the stopper portion ST is formed by utilizing the protruding portion 2S in which the storage portion HR is formed, thereby improving the space efficiency of the storage space formed by the base member 18 and the cover member 4 (upper cover member 4U).

[0135] The base member 18 may have a wall portion (fixed side pedestal portion 18D) located near each of two of the four corners 4E of the upper cover member 4U. In this case, a first conductive plate (fixed side metal member 5F) made of a non-magnetic metal may be fixed to the wall portion (fixed side pedestal portion 18D). The lens holding member 2 may have a fixed portion (movable side pedestal portion 2D) located near each of two other corners different from the two corners of the upper cover member 4U. In this case, a second conductive plate (movable side metal member 5M) made of a non-magnetic metal may be fixed to the fixed portion (movable side pedestal portion 2D). The shape memory alloy wire SA may be provided between the first conductive plate (fixed side metal member 5F) and the second conductive plate (movable side metal member 5M).

[0136] Specifically, the base member 18 may have a first fixed side pedestal portion 18D1 located near the second corner portion 4E2 and a second fixed side pedestal portion 18D2 located near the fourth corner portion 4E4, as shown in Fig. 10. In this case, the first fixed side terminal plate 5F1, the second fixed side terminal plate 5F2, the fifth fixed side terminal plate 5F5, and the sixth fixed side terminal plate 5F6 as the first conductor plate are fixed to the first fixed side pedestal portion 18D1, as shown in Fig. 3B. Also, the third fixed side terminal plate 5F3, the fourth fixed side terminal plate 5F4, the seventh fixed side terminal plate 5F7, and the eighth fixed side terminal plate 5F8 as the first conductor plate are fixed to the second fixed side pedestal portion 18D2, as shown in Fig. 3B. Also, as shown in FIG. 10, the lens holding member 2 may have a second movable side pedestal portion 2D2 located near the first corner portion 4E1 and a first movable side pedestal portion 2D1 located near the third corner portion 4E3. In this case, as shown in FIG. 3A, a first movable side terminal plate 5M1 and a second movable side terminal plate 5M2 as a second conductor plate are fixed to the first movable side pedestal portion 2D1. Also, as shown in FIG. 3A, a third movable side terminal plate 5M3 and a fourth movable side terminal plate 5M4 as a second conductor plate are fixed to the second movable side pedestal portion 2D2. Then, the shape memory alloy wire SA is provided between the fixed side metal member 5F and the movable side metal member 5M. Specifically, as shown in FIG. 6A, the first wire SA1 is provided between the first fixed side terminal plate 5F1 and the first movable side terminal plate 5M1, and the second wire SA2 is provided between the second fixed side terminal plate 5F2 and the first movable side terminal plate 5M1. The third wire SA3 is provided between the third fixed side terminal plate 5F3 and the second movable side terminal plate 5M2, and the fourth wire SA4 is provided between the fourth fixed side terminal plate 5F4 and the second movable side terminal plate 5M2. Similarly, the fifth wire SA5 is provided between the fifth fixed side terminal plate 5F5 and the third movable side terminal plate 5M3, and the sixth wire SA6 is provided between the sixth fixed side terminal plate 5F6 and the third movable side terminal plate 5M3.The seventh wire SA7 is provided between the seventh fixed side terminal plate 5F7 and the fourth movable side terminal plate 5M4, and the eighth wire SA8 is provided between the eighth fixed side terminal plate 5F8 and the fourth movable side terminal plate 5M4.

[0137] In this configuration, the fixed side metal member 5F and the movable side metal member 5M are both made of non-magnetic metal, so they do not adversely affect the magnetic attraction force generated between the first magnetic member 10 and the second magnetic member MG.

[0138] The preferred embodiments of the present invention have been described above in detail. However, the present invention is not limited to the above-described embodiments. Various modifications and substitutions may be applied to the above-described embodiments without departing from the scope of the present invention. Furthermore, each of the features described with reference to the above-described embodiments may be appropriately combined as long as there is no technical contradiction. [Explanation of symbols]

[0139] REFERENCE SIGNS LIST 1...Spacer member 2...Lens holding member 2D...Movable-side pedestal portion 2D1...First movable-side pedestal portion 2D2...Second movable-side pedestal portion 2S...Protruding portion 2S1...First protruding portion 2S2...Second protruding portion 2T...Protruding portion 2V...Projecting portion 4...Cover member 4A...First outer peripheral wall portion 4A1...First side plate portion 4A2...Second side plate portion 4A3...Third side plate portion 4A4...Fourth side plate portion 4B...Top plate portion 4C...Second outer peripheral wall portion 4C1...First side plate portion 4C2...Second side plate portion 4C3...Third side plate portion 4C4...Fourth side plate portion 4D...Bottom plate portion 4E... Corner 4E1... First corner 4E2... Second corner 4E3... Third corner 4E4... Fourth corner 4k... Opening 4L... Lower cover member 4m... Opening 4s... Storage section 4U... Upper cover member 5... Metal member 5F... Fixed side metal member 5F1... First fixed side terminal plate 5F2... Second fixed side terminal plate 5F3... Third fixed side terminal plate 5F4... Fourth fixed side terminal plate 5F5... Fifth fixed side terminal plate 5F6... Sixth fixed side terminal plate 5F7... Seventh fixed side terminal plate 5F8... Eighth fixed side terminal plate 5M... Movable side metal member 5M1... First movable side terminal plate 5M2...Second movable terminal plate 5M3...Third movable terminal plate 5M4...Fourth movable terminal plate 6...Leaf spring 6A...First leaf spring 6A1...First part 6A2...Second part 6A3...Third part 6A4...Fourth part 6A5...Fifth part 6AH1...First through hole 6AH2...Second through hole 6AH3...Third through hole 6AH4...Fourth through hole 6AH5...Fifth through hole 6AH6...Sixth through hole 6B...Second leaf spring 6B1...First part 6B2...Second part 6B3...Third part 6B4...Fourth part 6B5...Fifth part 6BH1: First through hole; 6BH2: Second through hole; 6BH3: Third through hole; 6BH4: Fourth through hole; 6BH5: Fifth through hole; 6BH6: Sixth through hole; 10: First magnetic member; 10A: First magnet; 10B: Second magnet; 12: Cylindrical portion18···Base member 18D···Fixed-side pedestal portion 18D1···First fixed-side pedestal portion 18D2···Second fixed-side pedestal portion 18E···Side portion 18E1···First side portion 18E2···Second side portion 18E3···Third side portion 18E4···Fourth side portion 18K···Opening 18S···Convex portion for stopper 18S1···Convex portion for first stopper 18S2···Convex portion for second stopper 18T···Protrusion 18V···Protrusion 101···Lens drive device AH···Rectangular hole BF···Bottom surface BW···Bottom CF···Outer periphery CM···Conductive member CM1···First conductive member CM2···Second conductive member CM3...Third conductive member CM4...Fourth conductive member CM5...Fifth conductive member CM6...Sixth conductive member CM7...Seventh conductive member CM8...Eighth conductive member CM9...Ninth conductive member CM10...Tenth conductive member CM11...Eleventh conductive member CP9...Ninth joint surface CP10...Tenth joint surface CSL...Lower opposing surface CSL1...Lower opposing surface CSL2...Lower opposing surface CSU...Upper opposing surface CSU1...Upper opposing surface CSU2...Upper opposing surface CT1~CT12...Connection part CV...Concave for stopper CV1...Concave for first stopper CV2...Concave for second stopper ED1...First connection part ED2...Second connection part ED3...3rd connection part ED4...4th connection part ED5...5th connection part ED6...6th connection part ED7...7th connection part ED8...8th connection part ED11...11th connection part EP...End face EW...Mounting surface EW1...1st mounting surface EW2...2nd mounting surface EW3...3rd mounting surface EW4...4th mounting surface HL1...Upper circular hole HL2...Lower circular hole HR...Accommodation part HR1...1st accommodation part HR2...2nd accommodation part J1~J4...Holding part JD...Light axis MB...Movable part MG...2nd magnetic part MG1...1st metal plate MG2...2nd metal plate MK...Drive mechanism RG...Fixed part RH...Through hole RS1, RS2...Recess SA...Shape memory alloy wire SA1...1st wire SA2...2nd wire SA3...3rd wire SA4...4th wire SA5...5th wire SA6...6th wire SA7...7th wireSA8...8th wire SB...Concave for stopper SB1...Concave for 1st stopper SB2...Concave for 2nd stopper SD...Jointing material SF...Inner surface ST...Stopper part ST1...1st stopper part ST2...2nd stopper part ST3...3rd stopper part ST4...4th stopper part TF...Top surface TM1...1st terminal part TM2...2nd terminal part TM3...3rd terminal part TM4...4th terminal part TM5...5th terminal part TM6...6th terminal part TM7...7th terminal part TM8...8th terminal part TM9...9th terminal part TM10...10th terminal part TM11...11th terminal part

Claims

1. a fixed member including a base member and a cover member; a lens holding member that is arranged in an accommodation space formed by the base member and the cover member and is capable of holding a lens body; a plurality of shape memory alloy wires disposed between the fixed member and a movable member including the lens holding member, the lens holding member is disposed on an upper side of the base member and is movable with respect to the base member by energizing the shape memory alloy wire; A lens driving device characterized in that a plurality of first magnetic members are arranged at a plurality of different positions on the lens holding member, and a plurality of second magnetic members corresponding to the plurality of first magnetic members are provided on the base member, each of the plurality of first magnetic members faces the corresponding second magnetic member in the optical axis direction and is attracted to the corresponding second magnetic member, and the movement of the lens holding member is regulated by the base member when current is not applied to the shape memory alloy wire.

2. the second magnetic member has an upper surface covered with the synthetic resin forming the base member, When the current is not applied, the base member and the lens holding member are in contact with each other. The lens driving device according to claim 1 .

3. The first magnetic member is a magnet.

3. The lens driving device according to claim 1.

4. an area of ​​a surface of the first magnetic member facing the second magnetic member is substantially equal to an area of ​​a surface of the second magnetic member facing the first magnetic member; The lens driving device according to claim 3 .

5. A conductive member that is electrically connected to the shape memory alloy wire is embedded in the base member, The second magnetic member is formed of the same metal as the conductive member. The lens driving device according to claim 3 .

6. the cover member has an outer peripheral wall portion and a top plate portion, and is rectangular in plan view when viewed in the optical axis direction; the first magnetic member is provided at two locations on the lens holding member corresponding to two diagonally arranged corners of the cover member, 6. The lens driving device according to claim 1.

7. the lens holding member has a cylindrical portion extending in the optical axis direction and housing the lens body therein, and protruding portions protruding from the cylindrical portion toward the two corners at positions corresponding to the two corners, respectively; The protruding portion is provided with a receiving portion having a bottom portion, The first magnetic member is accommodated in the accommodation portion.

7. The lens driving device according to claim 6.

8. the base member has a wall portion having an inner peripheral surface facing the outer peripheral surface of the protruding portion so as to cover the outer peripheral surface of the protruding portion, The protrusion and the wall constitute a stopper portion that restricts the movement of the lens holding member that tends to rotate at least around the optical axis. The lens driving device according to claim 7.

9. The base member has a wall portion located near each of the two corner portions, A first conductive plate made of a non-magnetic metal is fixed to the wall portion, the lens holding member has fixing portions located near two corners of the cover member that are different from the two corners, A second conductive plate made of a non-magnetic metal is fixed to the fixed portion, The shape memory alloy wire is provided between the first conductive plate and the second conductive plate.

8. The lens driving device according to claim 6 or 7.

10. A lens driving device according to any one of claims 1 to 9, The lens body; An imaging element facing the lens body, Camera module.

Images