JP7568190B2 - Lens holder drive unit - Google Patents

Description

This disclosure relates to a lens holder drive device.

Conventionally, imaging units have been known that include a lens frame (lens holder) that is moved in a direction parallel to the optical axis by a lead screw that is driven to rotate by an electric motor (see Patent Document 1).

JP 2014-149336 A

However, because the imaging unit described above uses an electric motor to move the lens holder, it is difficult to further reduce its size.

Therefore, it is desirable to provide a lens holder driving device that can be further miniaturized.

A lens holder driving device according to an embodiment of the present invention includes a fixed-side member, a movable-side member including a first lens holder capable of holding a first lens body and a second lens holder capable of holding a second lens body arranged to have the same optical axis as the first lens body, a first driving mechanism that moves the first lens holder in an optical axis direction, and a second driving mechanism that moves the second lens holder in the optical axis direction. In this lens holder driving device, the fixed-side member has a first surface and a second surface that are provided to face each other with the first lens holder and the second lens holder in between, a plurality of first coils are provided on the first surface, and the A second coil is provided on the second surface, a first drive magnet facing the first coil is fixed to the first lens holder, a second drive magnet facing the second coil is fixed to the second lens holder, the first drive magnet and the first coil constitute the first drive mechanism, the second drive magnet and the second coil constitute the second drive mechanism, and the first drive magnet is configured to face one of the multiple first coils in a direction perpendicular to the optical axis when located at a first position, and to face another one of the multiple first coils in a direction perpendicular to the optical axis when located at a second position different from the first position .

The lens holder driving device described above can be made even smaller.

FIG. 2 is a perspective view of a lens holder driving device. FIG. 2 is a schematic diagram of a camera module. FIG. 2 is an exploded perspective view of the lens holder driving device. FIG. FIG. FIG. 4 is an exploded perspective view of a fixed member constituting a lower member. FIG. 2 is an exploded perspective view of the coil assembly. FIG. FIG. 3A and 3B are top and bottom views of a lens holder. FIG. 2 is a cross-sectional view of the lens holder driving device. FIG. 4 is a top view of the members that constitute the drive mechanism. FIG. 4 is a top view of the members that constitute the drive mechanism. FIG. 4A and 4B are a perspective view and a front view of a holding mechanism. FIG. FIG. 2 is an exploded perspective view of a lens holding assembly. FIG. 2 is a cross-sectional view of a lens holding assembly. 4 is a block diagram showing an example of the configuration of a control system that controls the lens holder driving device. FIG.

The lens holder driving device 101 according to an embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view of the lens holder driving device 101. FIG. 2 is a schematic diagram of a camera module CM in a camera-equipped mobile device equipped with the lens holder driving device 101.

As shown in FIG. 1, the lens holder driving device 101 is configured to move the lens body LS along the optical axis JD of the lens body LS.

Note that X1 represents one direction of the X axis that constitutes the three-dimensional orthogonal coordinate system, and X2 represents the other direction of the X axis. Furthermore, Y1 represents one direction of the Y axis that constitutes 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 that constitutes the three-dimensional orthogonal coordinate system, and Z2 represents the other direction of the Z axis. In this embodiment, the optical axis JD extends parallel to the X axis. This is similar in the other figures.

The lens body LS is an example of an optical member and is composed of one or more lenses. Typically, the lens body LS is 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. In this embodiment, the lens body LS includes a first lens body LS1 and a second lens body LS2.

The lens holder driving device 101 is configured to be able to move the lens body LS along the optical axis direction by a driving mechanism DM (see FIG. 3) housed in a housing HS. The optical axis direction includes the direction of the optical axis JD of the lens body LS and a direction parallel to the optical axis JD. Specifically, the lens holder driving device 101 can move the first lens body LS1 along the optical axis direction as indicated by the double-headed arrow AR1, and can move the second lens body LS2 along the optical axis direction as indicated by the double-headed arrow AR2. That is, the lens holder driving device 101 can move each of the first lens body LS1 and the second lens body LS2 separately along the optical axis direction.

The housing HS is part of the fixed member FM and is composed of a cover member 1 and a base plate 2.

The lens holder driving device 101 is used in a camera module CM such as a periscope-type camera module, for example, as shown in FIG. 2. In the example shown in FIG. 2, the camera module CM mainly includes a mirror MR, a lens body LS, the lens holder driving device 101, and an image sensor IS. The mirror MR as a reflector may be a prism. In this embodiment, the mirror MR is configured to provide a flat reflecting surface.

The lens holder driving device 101 is typically positioned farther from the subject than the mirror MR, as shown in FIG. 2, and is configured to allow light LT from the subject reflected by the mirror MR to reach the image sensor IS through the lens body LS.

Next, the lens holder driving device 101 will be outlined with reference to Figures 3 to 5. Figure 3 is an exploded perspective view of the lens holder driving device 101, showing the cover member 1 separated from the lower member LM. Figures 4 and 5 are exploded perspective views of the lower member LM, showing the movable member MB separated from the fixed member FM. Specifically, Figure 4 is an exploded perspective view of the lower member LM as viewed from the Y1 side, and Figure 5 is an exploded perspective view of the lower member LM as viewed from the Y2 side.

As shown in FIG. 3, the lens holder driving device 101 includes a cover member 1, which is part of the fixed member FM, and a lower member LM.

The cover member 1 is configured to cover the lower member LM. In this embodiment, the cover member 1 is made by performing processes such as punching and drawing on a plate material made of a non-magnetic material such as austenitic stainless steel. Because it is made of a non-magnetic material, the cover member 1 does not have a negative magnetic effect on the drive mechanism that utilizes electromagnetic force.

As shown in FIG. 3, the cover member 1 has a bottomless box-like outer shape that defines the storage section 1s. The cover member 1 has a substantially rectangular cylindrical outer wall portion 1A and a substantially rectangular annular flat upper surface portion 1B that is continuous with the upper end (the end on the Z1 side) of the outer wall portion 1A. An opening is formed in the center of the upper surface portion 1B. The outer wall portion 1A includes a first side plate portion 1A1 to a fourth side plate portion 1A4. The first side plate portion 1A1 and the third side plate portion 1A3 face each other, and the second side plate portion 1A2 and the fourth side plate portion 1A4 face each other. The second side plate portion 1A2 and the fourth side plate portion 1A4 extend perpendicular to the first side plate portion 1A1 and the third side plate portion 1A3. That is, the first side plate portion 1A1 and the third side plate portion 1A3 extend perpendicularly to the second side plate portion 1A2 and the fourth side plate portion 1A4. The first side plate portion 1A1 has an opening for receiving light LT from the subject reflected by the mirror MR. Similarly, the third side plate portion 1A3 has an opening for allowing the light LT to reach the image sensor IS. In addition, the cover member 1 is joined to the base plate 2 by adhesive or the like, and together with the base plate 2, forms the housing HS.

As shown in Figures 4 and 5, the lower member LM includes a lens holder 3 and a drive magnet 6 as the movable member MB, and a base plate 2, a coil assembly 4, a coil holder 5, and a plate-shaped member 7 as the fixed member FM.

The base plate 2 is a member that constitutes part (bottom) of the housing HS. In this embodiment, the base plate 2, like the cover member 1, is made of a non-magnetic material such as austenitic stainless steel.

The lens holder 3 is configured to hold the lens body LS. In this embodiment, the lens holder 3 is formed by injection molding a synthetic resin such as liquid crystal polymer (LCP). The lens holder 3 also includes a first lens holder 3A configured to hold the first lens body LS1, and a second lens holder 3B configured to hold the second lens body LS2.

The drive magnet 6 is a component that constitutes the drive mechanism DM. In this embodiment, the drive magnet 6 includes a first drive magnet 6A (see FIG. 4) attached to the first lens holder 3A, and a second drive magnet 6B (see FIG. 5) attached to the second lens holder 3B.

In this embodiment, each of the first drive magnet 6A and the second drive magnet 6B is a permanent magnet magnetized with two poles, with the inner side (the side closer to the optical axis JD) magnetized to the N pole and the outer side magnetized to the S pole. Also, as shown in FIG. 4, the first drive magnet 6A is attached to the first lens holder 3A so that the outer side (S pole) is exposed. Similarly, as shown in FIG. 5, the second drive magnet 6B is attached to the second lens holder 3B so that the outer side (S pole) is exposed. However, each of the first drive magnet 6A and the second drive magnet 6B may be magnetized with the inner side (the side closer to the optical axis JD) magnetized to the S pole and the outer side magnetized to the N pole.

The first drive magnet 6A is arranged to face the coil attached to the first coil assembly 4A in a direction perpendicular to the optical axis JD and to be spaced apart from the coil. Similarly, the second drive magnet 6B is arranged to face the coil attached to the second coil assembly 4B in a direction perpendicular to the optical axis JD and to be spaced apart from the coil.

The coil holder 5 is configured to movably support the movable member MB and immovably support the coil assembly 4. In this embodiment, the coil holder 5 is formed by injection molding a synthetic resin such as liquid crystal polymer (LCP). The coil holder 5 and the base plate 2 form the base member BM. The base plate 2 and the coil holder 5 may be integrated. In this case, the base plate 2 may be formed from the same synthetic resin as the coil holder 5.

The coil assembly 4 is configured to hold the coil that constitutes the drive mechanism DM. In this embodiment, the coil assembly 4 includes a first coil assembly 4A that is arranged to face the first drive magnet 6A, and a second coil assembly 4B that is arranged to face the second drive magnet 6B. The substrate 41 (see FIG. 7) of the coil assembly 4 is formed of a flexible printed circuit board, and is attached to the coil holder 5 via a plate-shaped member 7 as shown in FIGS. 4 and 5. Note that in the attached drawings, for the sake of clarity, detailed illustrations of the winding state of the conductive wire that is surface-coated with an insulating material are omitted for the coil.

The plate-shaped member 7 is configured to support the coil assembly 4. In this embodiment, the plate-shaped member 7 is formed of a magnetic material and functions as a yoke. The plate-shaped member 7 includes a first plate-shaped member 7A that supports the first coil assembly 4A, and a second plate-shaped member 7B that supports the second coil assembly 4B.

Next, the fixed member FM constituting the lower member LM will be described in detail with reference to Figures 6 and 7. Figure 6 is an exploded perspective view of the fixed member FM constituting the lower member LM. Figure 7 is an exploded perspective view of the coil assembly 4.

As shown in FIG. 7, the coil assembly 4 includes a substrate 41, a coil set 42, a magnetic sensor set 43, and a lens holding assembly LH.

The substrate 41 is a member on which a conductive pattern is formed for supplying power to the coil set 42, the magnetic sensor set 43, etc. In this embodiment, the substrate 41 is formed of a flexible printed circuit board. The substrate 41 also includes a connection portion CP on which a conductive pattern is formed for supplying power to the electromagnetic mechanism EM (see FIG. 17) included in the lens holding assembly LH. Specifically, the connection portion CP is configured so that its upper surface (surface on the Z1 side) contacts the lower surface (surface on the Z2 side) of the lens holding assembly LH. In this embodiment, the substrate 41 includes a first substrate 41A of the first coil assembly 4A and a second substrate 41B of the second coil assembly 4B.

The coil set 42 is a component of the drive mechanism DM and is attached to the substrate 41. In this embodiment, the coil set 42 is a wound type coil and includes a first coil set 42A attached to the first substrate 41A of the first coil assembly 4A and a second coil set 42B attached to the second substrate 41B of the second coil assembly 4B.

The first coil set 42A includes a first coil 42A1 and a second coil 42A2. The first coil 42A1 and the second coil 42A2 are configured so that the direction in which current flows can be controlled separately. Similarly, the second coil set 42B includes a first coil 42B1 and a second coil 42B2. The first coil 42B1 and the second coil 42B2 are configured so that the direction in which current flows can be controlled separately.

The magnetic sensor set 43 is an example of a magnetic detection member. In this embodiment, the magnetic sensor set 43 is a set of Hall elements and is configured to detect the magnetic field generated by the drive magnet 6 attached to the lens holder 3.

Specifically, the magnetic sensor set 43 includes a first magnetic sensor set 43A attached to the first substrate 41A of the first coil assembly 4A, and a second magnetic sensor set 43B attached to the second substrate 41B of the second coil assembly 4B.

The first magnetic sensor set 43A includes a first hall element 43A1, a second hall element 43A2, and a third hall element 43A3. The first hall element 43A1 is disposed inside the first coil 42A1, the second hall element 43A2 is disposed between the first coil 42A1 and the second coil 42A2, and the third hall element 43A3 is disposed inside the second coil 42A2. Similarly, the second magnetic sensor set 43B includes a first hall element 43B1, a second hall element 43B2, and a third hall element 43B3. The first hall element 43B1 is disposed inside the first coil 42B1, the second hall element 43B2 is disposed between the first coil 42B1 and the second coil 42B2, and the third hall element 43B3 is disposed inside the second coil 42B2.

The lens holding assembly LH is a member for holding the lens holder 3 at a movement limit position, which is an example of a position on the end side of the movable range in the optical axis direction. The movement limit position means the position of the lens holder 3 when the lens holder 3 moves to the end of the movable range of the lens holder 3. However, the lens holding assembly LH may hold the lens holder 3 near the movement limit position in the optical axis direction. In this embodiment, as shown in FIG. 14, the lens holding assembly LH includes a first lens holding assembly LH1 for holding the first lens holder 3A at the movement limit position on the front side (X1 side), and a second lens holding assembly LH2 for holding the second lens holder 3B at the movement limit position on the rear side (X2 side). As shown in FIG. 7, the first lens holding assembly LH1 is attached to the connection part CP of the second substrate 41B in the second coil assembly 4B, and the second lens holding assembly LH2 is attached to the connection part CP of the first substrate 41A in the first coil assembly 4A.

When the first lens holder 3A is held at the movement limit position on the X1 side, the first lens holder 3A abuts against a stopper portion (not shown) provided on the fixed side member FM such as the coil holder 5. The same is true when the second lens holder 3B is held at the movement limit position on the X2 side.

Next, the details of the movable member MB will be described with reference to Figures 8 to 11. Figure 8 is an exploded perspective view of the movable member MB. Figure 9 is an exploded perspective view of the lens holder 3. Figure 10 is a top view and a bottom view of the lens holder 3. Specifically, Figure 10(A) shows a top view of the lens holder 3, and Figure 10(B) shows a bottom view of the lens holder 3. Figure 11 is a cross-sectional view of the lens holder driving device 101. Specifically, Figure 11(A) is a cross-sectional view of the lens holder driving device 101 in the YZ plane including the dashed line CL1 in Figure 1. Figure 11(B) is an enlarged view of the range R1 surrounded by the dashed line in Figure 11(A).

As shown in FIG. 8, the movable side member MB includes a lens holder 3 that holds the lens body LS, and an engagement member 10. Specifically, the lens holder 3 includes a first lens holder 3A that holds the first lens body LS1, and a second lens holder 3B that holds the second lens body LS2. The engagement member 10 includes a first engagement member 10A that is attached to the first lens holder 3A, and a second engagement member 10B that is attached to the second lens holder 3B.

The engagement member 10 is configured to be able to engage with the lens holding assembly LH when the lens holder 3 is at the movement limit position in the optical axis direction. In this embodiment, the engagement member 10 is formed of a metal plate. As shown in FIG. 14, the first engagement member 10A is configured to be able to engage with the first lens holding assembly LH1 when the first lens holder 3A is at the movement limit position on the X1 side. Similarly, the second engagement member 10B is configured to be able to engage with the second lens holding assembly LH2 when the second lens holder 3B is at the movement limit position on the X2 side.

As shown in FIG. 11(A), the lens holder 3 is configured to be sandwiched between the cover member 1 and the coil holder 5. Specifically, the lens holder 3 is configured to contact the upper surface of the coil holder 5 via the lower ball set 8, and to contact the ceiling surface (upper surface portion 1B) of the cover member 1 via the upper ball set 9.

As shown in FIG. 8, the lower ball set 8 includes a first lower ball set 8A that supports the first lens holder 3A, and a second lower ball set 8B that supports the second lens holder 3B. The first lower ball set 8A includes four balls (first ball 8A1 to fourth ball 8A4). Similarly, the second lower ball set 8B includes four balls (first ball 8B1 to fourth ball 8B4).

In this embodiment, the eight balls that make up the lower ball set 8 are made of metal. However, the eight balls that make up the lower ball set 8 may also be made of synthetic resin.

As shown in FIG. 8, the upper ball set 9 includes a first upper ball set 9A that supports the first lens holder 3A, and a second upper ball set 9B that supports the second lens holder 3B. The first upper ball set 9A includes four balls (first ball 9A1 to fourth ball 9A4). Similarly, the second upper ball set 9B includes four balls (first ball 9B1 to fourth ball 9B4).

In this embodiment, the eight balls that make up the upper ball set 9 are made of metal. However, the eight balls that make up the upper ball set 9 may also be made of synthetic resin.

As shown in FIG. 9, the lens holder 3 includes a lens carrier 30, a spring set 31, and a push bar set 32. In this embodiment, the lens carrier 30 and the push bar set 32 are made of synthetic resin, and the spring set 31 is made of metal.

The lens carrier 30 is a member for holding the lens body LS. In this embodiment, the lens carrier 30 includes a first lens carrier 30A for holding the first lens body LS1, and a second lens carrier 30B for holding the second lens body LS2. The first lens body LS1 is fixed to the first lens carrier 30A by an adhesive, and the second lens body LS2 is fixed to the second lens carrier 30B by an adhesive.

The first lens carrier 30A has a recess RS6 on the side (Y1 side) facing the first coil assembly 4A (see FIG. 4). The first drive magnet 6A is fitted into the recess RS6 and fixed with adhesive.

Similarly, the second lens carrier 30B has a recess RS7 (not visible in FIG. 9) on the side (the side on the Y2 side) facing the second coil assembly 4B (see FIG. 4). The second drive magnet 6B is fitted into the recess RS7 and fixed with an adhesive.

Furthermore, as shown in FIG. 8, the first lens carrier 30A has a convex portion PR and a raised portion BL on the upper surface (upper surface on the Y2 side) of the side portion facing the second coil assembly 4B. Similarly, as shown in FIG. 8, the second lens carrier 30B has a convex portion PR and a raised portion BL on the upper surface (upper surface on the Y1 side) of the side portion facing the first coil assembly 4A. The convex portion PR and the raised portion BL are structures for attaching the engaging member 10 to the lens carrier 30.

The protrusions PR are configured to pass through the openings AP formed in the engagement member 10. In this embodiment, the first lens carrier 30A is formed with two cylindrical protrusions PR. A recess for receiving adhesive is formed around each of the two protrusions PR. The same is true for the second lens carrier 30B.

The raised portion BL is configured to mesh with a notch CU formed in the engagement member 10. In this embodiment, the first lens carrier 30A is formed with one rectangular column-shaped raised portion BL. The same is true for the second lens carrier 30B.

The first engagement member 10A is fixed to the first lens carrier 30A by adhesive with the convex portion PR received in each of the two openings AP and with the cutout CU engaged with the raised portion BL of the first lens carrier 30A. Similarly, the second engagement member 10B is fixed to the second lens carrier 30B by adhesive with the convex portion PR received in each of the two openings AP and with the cutout CU engaged with the raised portion BL of the second lens carrier 30B.

As shown in FIG. 9, the spring set 31 is configured to bias the push bar set 32 upward (in the Z1 direction).

As shown in FIG. 8, the push bar set 32 is configured to hold the upper ball set 9 and press the upper ball set 9 against the ceiling surface of the cover member 1.

Specifically, the spring set 31 includes a first spring set 31A that biases upward the first push bar set 32A attached to the first lens carrier 30A, and a second spring set 31B that biases upward the second push bar set 32B attached to the second lens carrier 30B.

The first spring set 31A includes four coil springs (first coil spring 31A1 to fourth coil spring 31A4). Similarly, the second spring set 31B includes four coil springs (first coil spring 31B1 to fourth coil spring 31B4).

The first push bar set 32A includes two push bars (first push bar 32A1 and second push bar 32A2). Similarly, the second push bar set 32B includes two push bars (first push bar 32B1 and second push bar 32B2).

In this embodiment, the coil spring is fitted into a hole HL (see Figures 9 and 10(A)) formed in the lens carrier 30, and is configured to receive a cylindrical protrusion AX (see Figure 9) formed on the lower side (Z2 side) of the push bar set 32.

The holes HL formed in the first lens carrier 30A include a first hole HL1 to a fourth hole HL4. The first hole HL1 receives the first coil spring 31A1, the second hole HL2 receives the second coil spring 31A2, the third hole HL3 receives the third coil spring 31A3, and the fourth hole HL4 receives the fourth coil spring 31A4.

Similarly, the holes HL formed in the second lens carrier 30B include a first hole HL1 to a fourth hole HL4. The first hole HL1 receives the first coil spring 31B1, the second hole HL2 receives the second coil spring 31B2, the third hole HL3 receives the third coil spring 31B3, and the fourth hole HL4 receives the fourth coil spring 31B4.

As shown in FIG. 8, the first push bar 32A1 attached to the first lens carrier 30A has a first recess RS1 that rotatably receives the first ball 9A1 and a second recess RS2 that rotatably receives the second ball 9A2, and the second push bar 32A2 has a third recess RS3 that rotatably receives the third ball 9A3 and a fourth recess RS4 that rotatably receives the fourth ball 9A4.

Similarly, the first push bar 32B1 attached to the second lens carrier 30B has a first recess RS1 that rotatably receives the first ball 9B1 and a second recess RS2 that rotatably receives the second ball 9B2, and the second push bar 32B2 has a third recess RS3 that rotatably receives the third ball 9B3 and a fourth recess RS4 that rotatably receives the fourth ball 9B4.

As shown in FIG. 9, the protrusion AX formed on the first push bar 32A1 attached to the first lens carrier 30A has a first protrusion AX1 and a second protrusion AX2. The first protrusion AX1 is fitted inside the first coil spring 31A1, and the second protrusion AX2 is fitted inside the second coil spring 31A2. The protrusion AX formed on the second push bar 32A2 attached to the first lens carrier 30A has a third protrusion AX3 and a fourth protrusion AX4. The third protrusion AX3 is fitted inside the third coil spring 31A3, and the fourth protrusion AX4 is fitted inside the fourth coil spring 31A4.

Similarly, the protrusion AX formed on the first push bar 32B1 attached to the second lens carrier 30B has a first protrusion AX1 and a second protrusion AX2. The first protrusion AX1 is fitted inside the first coil spring 31B1, and the second protrusion AX2 is fitted inside the second coil spring 31B2. In addition, the protrusion AX formed on the second push bar 32B2 attached to the second lens carrier 30B has a third protrusion AX3 and a fourth protrusion AX4. The third protrusion AX3 is fitted inside the third coil spring 31B3, and the fourth protrusion AX4 is fitted inside the fourth coil spring 31B4.

As shown in FIG. 10(B), the lower surface (Z2 side surface) of the first lens carrier 30A is formed with a first recess RS1 to a fourth recess RS4 for receiving the first ball 8A1 to the fourth ball 8A4 that constitute the first lower ball set 8A, respectively. Similarly, the lower surface (Z2 side surface) of the second lens carrier 30B is formed with a first recess RS1 to a fourth recess RS4 for receiving the first ball 8B1 to the fourth ball 8B4 that constitute the second lower ball set 8B, respectively.

The lens holder 3 is supported by the coil holder 5 so as to be slidable in the optical axis direction via a lower ball set 8 arranged in a groove 5G (see Figures 4 and 5) formed on the upper surface of the coil holder 5.

The groove 5G includes a first groove 5G1 (see FIG. 4) that is located on the side closer to the second coil assembly 4B (Y2 side) and a second groove 5G2 that is located on the side closer to the first coil assembly 4A (Y1 side).

The first groove 5G1 is configured to receive the first ball 8A1 and the second ball 8A2 that constitute the first lower ball set 8A, and the first ball 8B1 and the second ball 8B2 that constitute the second lower ball set 8B.

The second groove 5G2 is configured to receive the third ball 8A3 and the fourth ball 8A4 that constitute the first lower ball set 8A, and the third ball 8B3 and the fourth ball 8B4 that constitute the second lower ball set 8B.

With the above-mentioned configuration, the lens holder 3 is sandwiched between the cover member 1 and the coil holder 5, and is configured to be movable along the optical axis direction. Specifically, as shown in FIG. 11, the first lens holder 3A is supported slidably in the optical axis direction by the first ball 8A1 (not visible in FIG. 11) and the second ball 8A2 constituting the first lower ball set 8A received in the first groove 5G1 of the coil holder 5, and the third ball 8A3 (not visible in FIG. 11) and the fourth ball 8A4 constituting the first lower ball set 8A received in the second groove 5G2 of the coil holder 5.

The first lens holder 3A is configured to urge the first push bar 32A1 upward by the first coil spring 31A1 (not visible in FIG. 11) and the second coil spring 31A2 constituting the first spring set 31A, and to urge the second push bar 32A2 upward by the third coil spring 31A3 (not visible in FIG. 11) and the fourth coil spring 31A4 constituting the first spring set 31A. The first lens holder 3A is configured to press the first ball 9A1 (not visible in FIG. 11) and the second ball 9A2 constituting the first upper ball set 9A supported by the first push bar 32A1 against the ceiling surface of the cover member 1, and to press the third ball 9A3 (not visible in FIG. 11) and the fourth ball 9A4 constituting the first upper ball set 9A supported by the second push bar 32A2 against the ceiling surface of the cover member 1. In this embodiment, the ceiling surface of the cover member 1 does not have a structure such as a groove 5G that guides the movement of the upper ball set 9. However, a structure such as a groove 5G may also be formed on the ceiling surface of the cover member 1.

With this configuration, the first lens holder 3A is clamped between the cover member 1 and the coil holder 5 so that it does not rattle and can move smoothly in the optical axis direction.

As shown in FIG. 11(B), the first groove 5G1 is configured so that the inclination of the inclined surface SL2 on the outer side (the side farther from the optical axis JD) relative to the horizontal plane is greater than the inclination of the inclined surface SL1 on the central side (the side closer to the optical axis JD) relative to the horizontal plane. The shapes of the first groove G1 and the second groove G2 are plane-symmetrical with respect to the XZ plane that includes the optical axis JD.

This configuration can realize centering of the first lens holder 3A. That is, with this configuration, the balls constituting the lower ball set 8 arranged in the groove 5G formed on the upper surface of the coil holder 5 can move slightly not only in the optical axis direction (direction parallel to the X axis) but also in a direction perpendicular to the optical axis (direction parallel to the Y axis). Therefore, when the first lens holder 3A is clamped between the cover member 1 and the coil holder 5, the XZ plane including the midpoint between the second ball 8A2 and the fourth ball 8A4 is automatically adjusted to coincide with the XZ plane including the midpoint between the first groove 5G1 and the second groove 5G2, and centering of the first lens holder 3A is appropriately realized. The same is true for the second lens holder 3B.

Next, the drive mechanism DM will be described with reference to Figures 12 and 13. Figures 12 and 13 are top views of the components that make up the drive mechanism DM. The drive mechanism DM is composed of a drive magnet 6 and a coil set 42. In Figures 12 and 13, for clarity, components other than those that make up the drive mechanism DM are omitted from the illustration, except for the lens body LS, the holding magnet 12, the substrate 41 of the coil assembly 4, and the magnetic sensor set 43. In addition, the coil set 42 is made transparent so that the position of the magnetic sensor set 43 can be seen. In addition, the north poles of the drive magnet 6 and the holding magnet 12 are marked with diagonal hatching.

Specifically, Fig. 12(A) shows the state when the first lens holder 3A (first lens body LS1) and the second lens holder 3B (second lens body LS2) are both away from the movement limit position and are separated from each other. Fig. 12(B) shows the state when the first lens holder 3A (first lens body LS1) and the second lens holder 3B (second lens body LS2) are both at the movement limit position. Fig. 13(A) shows the state when the first lens holder 3A (first lens body LS1) is away from the movement limit position, the second lens holder 3B (second lens body LS2) is at the movement limit position, and the two are in contact. FIG. 13B shows the state when the first lens holder 3A (first lens body LS1) is at the movement limit position, the second lens holder 3B (second lens body LS2) is away from the movement limit position, and the two are in contact.

The driving mechanism DM is configured to be able to move the lens holder 3 in the optical axis direction. In this embodiment, the driving mechanism DM is configured to generate a driving force by the current flowing through the coil set 42 and the magnetic field generated by the driving magnet 6, and to be able to move the lens holder 3 along the optical axis JD.

Specifically, the drive mechanism DM includes a first drive mechanism DM1 that moves the first lens holder 3A in the optical axis direction, and a second drive mechanism DM2 that moves the second lens holder 3B in the optical axis direction.

The first drive mechanism DM1 includes a first coil set 42A attached to the first substrate 41A of the first coil assembly 4A and a first drive magnet 6A attached to the first lens carrier 30A.

The second drive mechanism DM2 includes a second coil set 42B attached to the second substrate 41B of the second coil assembly 4B and a second drive magnet 6B attached to the second lens carrier 30B.

The holding magnet 12 is configured to be able to hold the lens holder 3 at the movement limit position by magnetic force. In this embodiment, the holding magnet 12 includes a first holding magnet 12A that magnetically holds the first lens holder 3A at the movement limit position, and a second holding magnet 12B that magnetically holds the second lens holder 3B at the movement limit position.

In this embodiment, each of the first holding magnet 12A and the second holding magnet 12B is a permanent magnet magnetized with two poles, with the inner side (the side closer to the optical axis JD) magnetized to the N pole and the outer side magnetized to the S pole. As shown in FIG. 6, the holding magnet 12 is attached to the coil holder 5 so as not to directly face the lens holder 3 (driving magnet 6), that is, so as to indirectly face the driving magnet 6 with a part of the coil holder 5 in between. However, each of the first holding magnet 12A and the second holding magnet 12B may be magnetized with the inner side (the side closer to the optical axis JD) magnetized to the S pole and the outer side magnetized to the N pole to match the magnetic pole of the driving magnet 6.

The first holding magnet 12A includes a front magnet 12A1 that holds the first lens holder 3A at its movement limit position on the X1 side, and a rear magnet 12A2 that holds the first lens holder 3A at its movement limit position on the X2 side.

Similarly, the second holding magnet 12B includes a front magnet 12B1 that holds the second lens holder 3B at its movement limit position on the X1 side, and a rear magnet 12B2 that holds the second lens holder 3B at its movement limit position on the X2 side.

The first holding magnet 12A is then fitted into the recess RS5 of the coil holder 5 and fixed with adhesive, as shown in FIG. 6. The same is true for the second holding magnet 12B.

Specifically, as shown in FIG. 12(B), the front magnet 12A1 of the first holding magnet 12A is positioned so as to attract the first driving magnet 6A by the attractive force acting between it and the first driving magnet 6A attached to the first lens holder 3A at the limit of movement on the X1 side.

As shown in FIG. 13(A), the rear magnet 12A2 of the first holding magnet 12A is positioned so as to attract the first driving magnet 6A by the attractive force acting between it and the first driving magnet 6A attached to the first lens holder 3A at the limit of movement on the X2 side.

Similarly, as shown in FIG. 13B, the front magnet 12B1 of the second holding magnet 12B is positioned so as to attract the second driving magnet 6B by the attractive force acting between it and the second driving magnet 6B attached to the second lens holder 3B at the limit of movement on the X1 side.

As shown in FIG. 12(B), the rear magnet 12B2 of the second holding magnet 12B is positioned so as to attract the second driving magnet 6B by the attractive force acting between it and the second driving magnet 6B attached to the second lens holder 3B at the limit of movement on the X2 side.

Next, we will explain the relationship between the magnetic poles of the first drive magnet 6A and the magnetic poles of the first coil set 42A when the first lens holder 3A, which is at the movement limit position on the X1 side, is moved to the movement limit position on the X2 side.

When the first lens holder 3A is at the limit of movement on the X1 side, the first drive magnet 6A is in a position facing the first coil 42A1 of the first coil set 42A, as shown in FIG. 13B. However, the central axis M1 at the center position in the optical axis direction of the first drive magnet 6A does not coincide with the central axis L1 at the center position in the optical axis direction of the first coil 42A1. If the central axis M1 and the central axis L1 coincide, when the first coil 42A1 is excited, there is a risk that the first drive magnet 6A cannot be moved away by repulsive force (repulsive force). Note that the central axis M1 is a straight line parallel to the Y axis passing through the center point of the first drive magnet 6A, and the central axis L1 is a straight line parallel to the Y axis passing through the center point of the first coil 42A1. The same applies to the central axes L2, L3, L4, and M2 described later.

When the first coil 42A1 is not excited, the south pole of the first drive magnet 6A is attracted to the north pole of the front magnet 12A1 of the first holding magnet 12A, and the first drive magnet 6A (first lens holder 3A) is held at the limit of movement on the X1 side.

When the first coil 42A1 is excited so that the side of the first coil 42A1 facing the first drive magnet 6A (Y2 side) becomes the S pole, i.e., so that the first drive magnet 6A and the first coil 42A1 repel each other, the first drive magnet 6A moves along the optical axis direction to the X2 side, as shown in FIG. 12(A).

Then, when the second coil 42A2 of the first coil set 42A is excited so that the side (Y2 side) of the second coil 42A2 facing the first drive magnet 6A becomes the north pole, i.e., so that the first drive magnet 6A and the second coil 42A2 attract each other, the first drive magnet 6A moves further toward the X2 side along the optical axis direction, as shown in FIG. 13(A).

When the first lens holder 3A is at the limit of movement on the X2 side, the first drive magnet 6A is in a position facing the second coil 42A2, as shown in FIG. 13(A). However, for the reasons described above, the central axis M1 of the first drive magnet 6A does not coincide with the central axis L2, which is located at the center position in the optical axis direction of the second coil 42A2.

When the first lens holder 3A is at the limit of movement on the X2 side and the second coil 42A2 is not excited, the south pole of the first drive magnet 6A is attracted to the north pole of the rear magnet 12A2 of the first holding magnet 12A, and the first drive magnet 6A (first lens holder 3A) is held at the limit of movement on the X2 side.

Similarly, when the second lens holder 3B is at the limit of movement on the X1 side, the second drive magnet 6B is positioned opposite the first coil 42B1 of the second coil set 42B, as shown in FIG. 13(B). However, for the reasons described above, the central axis M2 at the center position in the optical axis direction of the second drive magnet 6B does not coincide with the central axis L3 at the center position in the optical axis direction of the first coil 42B1.

When the first coil 42B1 is not excited, the S pole of the second drive magnet 6B is attracted to the N pole of the front magnet 12B1 of the second holding magnet 12B, and the second drive magnet 6B (second lens holder 3B) is held at the limit of its movement on the X1 side.

When the first coil 42B1 is excited so that the side of the first coil 42B1 facing the second drive magnet 6B (Y1 side) becomes the S pole, i.e., so that the second drive magnet 6B and the first coil 42B1 repel each other, the second drive magnet 6B moves to the X2 side along the optical axis direction, as shown in FIG. 12(A).

Then, when the second coil 42B2 of the second coil set 42B is excited so that the side (Y1 side) facing the second drive magnet 6B becomes the north pole, i.e., so that the second drive magnet 6B and the second coil 42B2 attract each other, the second drive magnet 6B moves further toward the X2 side along the optical axis direction, as shown in FIG. 13(A).

When the second lens holder 3B is at the limit of movement on the X2 side, the second drive magnet 6B is in a position facing the second coil 42B2, as shown in FIG. 13(A). However, for the reasons described above, the central axis M2 of the second drive magnet 6B does not coincide with the central axis L4, which is located at the center position in the optical axis direction of the second coil 42B2.

When the second lens holder 3B is at the limit of movement on the X2 side and the second coil 42B2 is not excited, the S pole of the second drive magnet 6B is attracted to the N pole of the rear magnet 12B2 of the second holding magnet 12B, and the second drive magnet 6B (second lens holder 3B) is held at the limit of movement on the X2 side.

Next, the sizes of the lens body LS, the drive magnet 6, and the coil set 42 will be described. In this embodiment, as shown in FIG. 13(B), the width W1, which is the dimension in the optical axis direction of the first lens body LS1, is larger than the width W2, which is the dimension in the optical axis direction of the second lens body LS2. Therefore, as shown in FIGS. 4 and 5, the width W3 of the first lens holder 3A that holds the first lens body LS1 is larger than the width W4 of the second lens holder 3B that holds the second lens body LS2.

Also, as shown in FIG. 13(A), the width W5 of the first drive magnet 6A is larger than the width W6 of the second drive magnet 6B. In this embodiment, the height of the first drive magnet 6A is the same as the height of the second drive magnet 6B.

The width W7 of each of the first coil 42A1 and second coil 42A2 constituting the first coil set 42A is greater than the width W8 of each of the first coil 42B1 and second coil 42B2 constituting the second coil set 42B. In this embodiment, as shown in FIG. 7, the height H1 of each of the first coil 42A1 and second coil 42A2 constituting the first coil set 42A is the same as the height H2 of the first coil 42B1 and second coil 42B2 constituting the second coil set 42B.

Also, as shown in FIG. 13B, the width W9 of the arrangement area of the first coil set 42A partially overlaps with the width W10 of the arrangement area of the second coil set 42B in the optical axis direction. The overlapping portion has a width W11.

The placement area of the first coil set 42A refers to the area on the first substrate 41A of the first coil assembly 4A where coils can be placed. In this embodiment, the first coil 42A1 is placed at the right end (the end on the X1 side) of the placement area, and the second coil 42A2 is placed at the left end (the end on the X2 side) of the placement area. Therefore, the width between the right end of the first coil 42A1 and the left end of the second coil 42A2 is the width W9 of the placement area. The same applies to the placement area of the second coil set 42B.

Also, as shown in FIG. 13(A), the width W12, which is the distance between the first coil 42A1 and the second coil 42A2 constituting the first coil set 42A, is larger than the width W13, which is the distance between the first coil 42B1 and the second coil 42B2 constituting the second coil set 42B. This is because the width W5 of the first drive magnet 6A is larger than the width W6 of the second drive magnet 6B.

Next, referring to Figs. 14 to 18, the holding mechanism HM that mechanically holds the lens holder 3 at the movement limit position will be described. Fig. 14 is a perspective view of the lower member LM, showing the state in which the lens holder 3 is mechanically held at the movement limit position by the holding mechanism HM. Fig. 15 is a perspective view and a front view (side view seen from the X1 side) of the holding mechanism HM. Fig. 16 is an exploded perspective view of the fixed member FM (excluding the cover member 1). Fig. 17 is an exploded perspective view of the lens holding assembly LH. Fig. 18 is a cross-sectional view of the lens holding assembly LH. Specifically, Fig. 18 is a cross-sectional view of the first lens holding assembly LH1 in the YZ plane including the dashed line CL2 in Fig. 16. Note that in Fig. 18, the upper holding magnet 22, the plunger 25, and the lower holding magnet 26 have N poles hatched, so the hatching indicating that it is a cross section has been omitted.

The holding mechanism HM includes a lens holding assembly LH and an engagement member 10. In this embodiment, as shown in FIG. 14, the holding mechanism HM includes a first holding mechanism HM1 that mechanically holds the first lens holder 3A at the front (X1 side) movement limit position, and a second holding mechanism HM2 that mechanically holds the second lens holder 3B at the rear (X2 side) movement limit position.

The first holding mechanism HM1 includes a first lens holding assembly LH1 and a first engagement member 10A. The second holding mechanism HM2 includes a second lens holding assembly LH2 and a second engagement member 10B.

As shown in FIG. 15, the first lens holding assembly LH1 is configured so that the locking portion 25e can be moved forward and backward (up and down) in a direction parallel to the Z axis. FIG. 15 shows the relationship between the first lens holding assembly LH1 fixed to the second substrate 41B of the second coil assembly 4B and the first engagement member 10A fixed to the first lens carrier 30A of the first lens holder 3A. Specifically, FIGS. 15(A1) and 15(A2) show the state when the locking portion 25e is pushed upward, and FIGS. 15(B1) and 15(B2) show the state when the locking portion 25e is pulled downward.

In this embodiment, the first lens holding assembly LH1 is configured so that the engaging portion 25e can be moved up and down by an electromagnetic mechanism EM (see FIG. 17) located inside the first lens holding assembly LH1. The same is true for the second lens holding assembly LH2.

The electromagnetic mechanism EM in the first lens holding assembly LH1 is disposed so as to face side SB2 on the side (Y2 side) of the first lens holder 3A opposite side SB1 on the side (Y1 side) where the first drive magnet 6A is provided. In other words, the electromagnetic mechanism EM in the first lens holding assembly LH1 is disposed away from the first drive magnet 6A. This is to prevent interference between the magnetism generated by the first drive magnet 6A and the magnetism generated by the electromagnetic mechanism EM. The same applies to the positional relationship between the electromagnetic mechanism EM and the second drive magnet 6B in the second lens holding assembly LH2.

As shown in FIG. 15 (A2), the locking portion 25e is configured so that when pushed upward, its end face is located above the upper surface of the engagement member 10. That is, when pushed upward, the locking portion 25e is configured to engage with the notch CT (see FIG. 8) formed in the engagement member 10. Hereinafter, this state will be referred to as the "engaged state". Also, as shown in FIG. 15 (B2), the locking portion 25e is configured so that when pulled downward, its end face is located below the lower surface of the engagement member 10. That is, when pulled downward, the locking portion 25e is configured not to engage with the notch CT (see FIG. 8) formed in the engagement member 10. Hereinafter, this state will be referred to as the "disengaged state". The notch CT is an example of an engagement portion, and may be formed as a through portion (opening (through hole)) that matches the shape of the locking portion 25e. Furthermore, the engaging portion and the locking portion 25e may have any structure as long as they can engage with each other, that is, as long as they can selectively realize an engaged state and a disengaged state.

As shown in FIG. 16, the first lens holding assembly LH1 is fitted and fixed in a recess RS8 formed in the coil holder 5 when attached to the second substrate 41B of the second coil assembly 4B. Similarly, the second lens holding assembly LH2 is fitted and fixed in a recess RS9 formed in the coil holder 5 when attached to the first substrate 41A of the first coil assembly 4A.

Specifically, as shown in FIG. 17, the first lens holding assembly LH1 is composed of an upper cover 20, a yoke 21, an upper holding magnet 22, a bobbin 23, a coil 24, a plunger 25, a lower holding magnet 26, a coil spring 27, and a lower cover 28.

The upper holding magnet 22, the bobbin 23, the plunger 25, the lower holding magnet 26, and the coil spring 27 constitute the locking mechanism LK, and the yoke 21, the upper holding magnet 22, the bobbin 23, the coil 24, the plunger 25, and the lower holding magnet 26 constitute the electromagnetic mechanism EM. The same is true for the second lens holding assembly LH2.

The upper cover 20 is a substantially rectangular plate-like member that forms the upper surface of the first lens holding assembly LH1. In this embodiment, the upper cover 20 is made of a magnetic material and is configured to function as a yoke. The upper cover 20 has an opening 20k in the center through which the locking portion 25e formed on the upper end of the plunger 25 penetrates. The upper cover 20 has six openings 20h through which six protrusions 23p formed on the upper end of the bobbin 23 penetrate. In FIG. 17, only one of the six protrusions 23p is indicated by a reference symbol, and only one of the six openings 20h is indicated by a reference symbol. One of the six openings 20h is formed as a notch that opens outward.

The yoke 21 is a member for efficiently applying the magnetic fields generated by the upper holding magnet 22, the coil 24, and the lower holding magnet 26. In this embodiment, the yoke 21 is made of a magnetic material and is configured to cooperate with the upper cover 20 and the lower cover 28 and surround the upper holding magnet 22, the bobbin 23, the coil 24, the plunger 25, the lower holding magnet 26, and the coil spring 27.

The upper holding magnet 22 is a member for magnetically maintaining the engagement state between the locking portion 25e of the plunger 25 and the engagement member 10. Specifically, the upper holding magnet 22 is arranged so as to attract the plunger 25, which is made of a magnetic material, upward (Z1 direction). In this embodiment, the upper holding magnet 22 includes a first magnet 22A and a second magnet 22B. The first magnet 22A and the second magnet 22B are both permanent magnets magnetized with two poles, and as shown in FIG. 18, the lower side (Z2 side) is magnetized with the N pole and the upper side (Z1 side) is magnetized with the S pole. The first magnet 22A is fitted into the recess RS10 formed in the bobbin 23 and fixed with an adhesive. Similarly, the second magnet 22B is fitted into the recess RS11 formed in the bobbin 23 and fixed with an adhesive.

Note that Fig. 18(A) shows the state when the locking portion 25e is pulled downward, and Fig. 18(B) shows the state when the locking portion 25e is pushed upward. Fig. 18 also shows that the stroke amount, which is the distance between the end face of the locking portion 25e when it is pushed upward and the end face of the locking portion 25e when it is pulled downward, is a value SK.

As shown in FIG. 18, each of the first magnet 22A and the second magnet 22B is attached to the bobbin 23 with its S pole facing upward (Z1 direction). However, each of the first magnet 22A and the second magnet 22B may be attached to the bobbin 23 with its N pole facing upward (Z1 direction).

The bobbin 23 is configured to support the upper cover 20, the yoke 21, the upper holding magnet 22, the coil 24, the plunger 25, the lower holding magnet 26, the coil spring 27, and the lower cover 28. In this embodiment, the bobbin 23 is formed by injection molding a synthetic resin such as liquid crystal polymer (LCP).

Specifically, the bobbin 23 is configured so that the coil 24 is disposed around the constricted portion 23n, as shown in FIG. 17.

As shown in FIG. 18, the bobbin 23 is configured to receive the plunger 25, the lower holding magnet 26, and the coil spring 27 in a cavity CV formed therein. The plunger 25 is disposed in the cavity CV so that it can slide vertically (in the Z-axis direction) within the cavity CV. The coil spring 27 is disposed in a compressed state between the plunger 25 and the lower cover 28 so that it can bias the plunger 25 upward (in the Z1 direction).

The coil 24 is configured to be able to excite the plunger 25, which is made of a magnetic material. In this embodiment, the coil 24 is wound around the constricted portion 23n of the plunger 25. Specifically, when a current flows in the first direction of the wire constituting the coil 24, the coil 24 excites the upper part (Z1 side) of the plunger 25 to the N pole, and excites the lower part (Z2 side) of the plunger 25 to the S pole, as shown in FIG. 18(A). Conversely, when a current flows in the second direction (opposite to the first direction) of the wire constituting the coil 24, the coil 24 excites the upper part (Z1 side) of the plunger 25 to the S pole, and excites the lower part (Z2 side) of the plunger 25 to the N pole, as shown in FIG. 18(B).

The plunger 25 is configured so that it can slide vertically (in the Z-axis direction) within the cavity CV of the bobbin 23, and so that a portion of it can mesh with the engagement member 10. In this embodiment, the plunger 25 is disposed within the cavity CV while being biased upward (in the Z1 direction) by the coil spring 27. The plunger 25 is also formed of a magnetic material so that it is excited by the coil 24. Specifically, the plunger 25 has a substantially rectangular parallelepiped main body 25m and a prismatic locking portion 25e that protrudes upward from the main body 25m.

The lower holding magnet 26 is a member for magnetically maintaining the disengaged state between the locking portion 25e of the plunger 25 and the engaging member 10. Specifically, the lower holding magnet 26 is arranged so as to be able to attract the plunger 25, which is made of a magnetic material, downward (Z2 direction). In this embodiment, the lower holding magnet 26 includes a first magnet 26A and a second magnet 26B. The first magnet 26A and the second magnet 26B are both permanent magnets magnetized with two poles, and as shown in FIG. 18, the upper side (Z1 side) is magnetized to the N pole, and the lower side (Z2 side) is magnetized to the S pole. That is, when the lower side (Z2 side) of each of the first magnet 22A and the second magnet 22B constituting the upper holding magnet 22 is attached to the N pole, the first magnet 26A and the second magnet 26B constituting the lower holding magnet 26 are arranged so that the upper side (Z1 side) is the N pole.

The first magnet 26A is fixed by adhesive in contact with a step SP1 formed in the cavity CV of the bobbin 23. Similarly, the second magnet 26B is fixed by adhesive in contact with a step SP2 formed in the cavity CV of the bobbin 23.

The coil spring 27 is an example of a biasing member, and is configured to bias the plunger 25 upward (in the Z1 direction) within the cavity CV of the bobbin 23. In this embodiment, the coil spring 27 is disposed in the cavity CV together with the plunger 25. Specifically, the coil spring 27 is disposed in a compressed state within the cavity CV so that one end contacts the lower end face (Z2 side) of the main body 25m of the plunger 25, and the other end contacts the upper face (Z1 side face) of the lower cover 28 attached to the bobbin 23.

The lower cover 28 is a substantially rectangular plate-like member that forms the lower surface of the first lens holding assembly LH1. In this embodiment, the lower cover 28 is made of a magnetic material and is configured to function as a yoke. The lower cover 28 also has six openings 28h through which six protrusions 23q formed at the lower end of the bobbin 23 penetrate. Note that in FIG. 17, only one of the six protrusions 23q is indicated by a reference symbol, and only one of the six openings 28h is indicated by a reference symbol. One of the six openings 28h is formed as a notch that opens outward.

In addition, in this embodiment, the upper cover 20 and the lower cover 28 are configured to have the same shape. This is to reduce the number of parts.

The electromagnetic mechanism EM is a mechanism for moving the plunger 25 up and down by electromagnetic force within the cavity CV of the bobbin 23. In this embodiment, the electromagnetic mechanism EM is mainly composed of an upper holding magnet 22, a bobbin 23, a coil 24, a plunger 25, and a lower holding magnet 26.

When a current flows in the first direction of the wire that constitutes the coil 24, the upper part of the plunger 25 is excited to the N pole, and the lower part is excited to the S pole, as shown in FIG. 18(A). Therefore, the plunger 25 moves in the direction indicated by the arrow AR3 due to the repulsive force between the N pole of the upper holding magnet 22 and the N pole of the upper part of the plunger 25, and the attractive force between the N pole of the lower holding magnet 26 and the S pole of the lower part of the plunger 25. At this time, the plunger 25 moves downward while compressing the coil spring 27 until the gap between the plunger 25 and the lower holding magnet 26 becomes the value GP1. Then, the state in which the gap between the plunger 25 and the lower holding magnet 26 becomes the value GP1, i.e., the state shown in FIG. 18(A), is maintained by the attractive force between the N pole of the lower holding magnet 26 and the non-excited plunger 25, even when the supply of current to the coil 24 is stopped. In this embodiment, the plunger 25 and the lower holding magnet 26 are configured not to come into contact with each other. If the plunger 25 and the lower holding magnet 26 come into contact with each other, a relatively large force would be required to separate them.

When a current flows in the second direction of the wire constituting the coil 24, the upper portion of the plunger 25 is excited to the S pole and the lower portion is excited to the N pole, as shown in FIG. 18(B). Therefore, the plunger 25 moves in the direction indicated by the arrow AR4 due to the attraction force between the N pole of the upper holding magnet 22 and the S pole of the upper portion of the plunger 25, the repulsion force between the N pole of the lower holding magnet 26 and the N pole of the lower portion of the plunger 25, and the restoring force of the coil spring 27. At this time, the plunger 25 moves upward until the distance between the plunger 25 and the upper holding magnet 22 becomes the value GP2, that is, until the shoulder portion 25s of the plunger 25 (see FIG. 18(A)) comes into contact with the step portion SP3 (see FIG. 18(A)) formed in the cavity CV of the bobbin 23 as a stopper portion. In this embodiment, the plunger 25 and the upper holding magnet 22 are configured not to come into contact with each other. This is because if the plunger 25 and the upper holding magnet 22 come into contact with each other, a relatively large force is required to separate them.

With this configuration, the electromagnetic mechanism EM can move the plunger 25 up and down within the cavity CV of the bobbin 23 by a predetermined stroke amount (value SK).

The locking mechanism LK is a mechanism for mechanically fixing the movement of the plunger 25 when the engaging portion 25e of the plunger 25 engages with the notch CT (see FIG. 8) of the engagement member 10. In this embodiment, the locking mechanism LK is mainly composed of the upper holding magnet 22, the bobbin 23, the plunger 25, and the coil spring 27.

The state in which the shoulder 25s of the plunger 25 is in contact with the step SP3 formed in the cavity CV of the bobbin 23, i.e., the state shown in FIG. 18(B), is maintained by the attractive force between the north pole of the upper holding magnet 22 and the upper part of the plunger 25, even when the supply of current to the coil 24 is stopped.

With this configuration, even if the supply of current to the coil 24 is stopped, the locking mechanism LK can bring about a state as shown in FIG. 15 (A1) and FIG. 15 (A2), i.e., a state in which the lens carrier 30 is held at the movement limit position by the engagement of the engagement portion 25e and the cutout CT.

In the above embodiment, as shown in FIG. 14, the holding mechanism HM is configured to include a first holding mechanism HM1 that holds the first lens holder 3A at the front (X1 side) movement limit position, and a second holding mechanism HM2 that holds the second lens holder 3B at the rear (X2 side) movement limit position. That is, the holding mechanism HM is configured to hold the first lens holder 3A at the front movement limit position, and the second lens holder 3B at the rear movement limit position. However, the holding mechanism HM may be configured to hold the first lens holder 3A and the second lens holder 3B together at either the front or rear movement limit position.

For example, as shown in FIG. 13A, when the first lens holder 3A and the second lens holder 3B are at their rear (X2) movement limit positions, the holding mechanism HM may be configured to hold both the first lens holder 3A and the second lens holder 3B together by engaging a notch CT of an engagement member attached to the Y1 end of the first lens holder 3A located forward (X1 side) of the second lens holder 3B with a locking portion 25e of a plunger 25 constituting the second lens holding assembly LH2 attached to the rear end of the first substrate 41A. In this case, the first engagement member 10A, the second engagement member 10B, and the first lens holding assembly LH1 may be omitted.

Alternatively, as shown in FIG. 13B, for example, when the first lens holder 3A and the second lens holder 3B are at their front (X1) movement limit positions, the holding mechanism HM may be configured to hold both the first lens holder 3A and the second lens holder 3B together by engaging a notch CT of an engagement member attached to the Y2 end of the second lens holder 3B located rearward (X2) from the first lens holder 3A with a locking portion 25e of a plunger 25 constituting a first lens holding assembly LH1 attached to the front end of the second substrate 41B. In this case, the first engagement member 10A, the second engagement member 10B, and the second lens holding assembly LH2 may be omitted.

In this way, the holding mechanism HM may be configured to hold both the first lens holder 3A and the second lens holder 3B together using one engagement member and one lens holding assembly.

Next, control of the lens holder driving device 101 mounted on the camera-equipped mobile device will be described with reference to FIG. 19. FIG. 19 is a block diagram showing an example of the configuration of the control system SYS that controls the lens holder driving device 101.

The control system SYS mainly includes as its components the first Hall element 43A1, the second Hall element 43A2, and the third Hall element 43A3 in the first magnetic sensor set 43A, the first Hall element 43B1, the second Hall element 43B2, and the third Hall element 43B3 in the second magnetic sensor set 43B, the first coil 42A1 and the second coil 42A2 in the first coil set 42A, the first coil 42B1 and the second coil 42B2 in the second coil set 42B, the coil 24 in the first lens holding assembly LH1, and the coil 24 in the second lens holding assembly LH2, which are arranged in the lens holder driving device 101.

The control system SYS also includes as components an input device ID, a control device CTR, and a power source CS, which are arranged outside the lens holder driving device 101.

The input device ID is a device for accepting input to the control device CTR. In the example shown in FIG. 19, the input device ID is a touch panel installed on a mobile device with a camera.

The control device CTR is configured to be able to control a power source CS capable of supplying current to the lens holder driving device 101. In the example shown in FIG. 19, the control device CTR is configured to control the power source CS based on information from the input device ID, the first hall element 43A1, the second hall element 43A2, and the third hall element 43A3 in the first magnetic sensor set 43A, and the first hall element 43B1, the second hall element 43B2, and the third hall element 43B3 in the second magnetic sensor set 43B, etc.

The power supply CS is configured to supply current individually to each of the first coil 42A1 and the second coil 42A2 in the first coil set 42A, the first coil 42B1 and the second coil 42B2 in the second coil set 42B, the coil 24 in the first lens holding assembly LH1, and the coil 24 in the second lens holding assembly LH2.

In the example shown in FIG. 19, the control device CTR controls the power source CS using a PWM control method, thereby supplying the appropriate amount of current to each component at the appropriate timing.

Specifically, when the control device CTR receives a camera start signal from the input device ID, it PWM controls the power supply CS to supply current to each of the coils 24 in the first lens holding assembly LH1 and the coils 24 in the second lens holding assembly LH2.

The camera activation signal is a signal for activating the camera mounted on the camera-equipped mobile device. In the example shown in FIG. 19, the camera activation signal is output by a touch panel serving as an input device ID when a camera icon displayed on a touch panel display mounted on the camera-equipped mobile device is touched.

When the coil 24 in the first lens holding assembly LH1 receives a current from the power source CS, it moves the plunger 25 downward (in the Z2 direction) as shown in FIG. 18(A). That is, the coil 24 retracts the end face of the locking portion 25e of the plunger 25, which was located higher than the upper surface of the first engaging member 10A as shown in FIG. 15(A2), to a position lower than the lower surface of the first engaging member 10A as shown in FIG. 15(B2). This is to release the engagement between the first engaging member 10A and the locking portion 25e. This release allows the first lens holder 3A to move freely in the optical axis direction. The same applies to the release of the engagement between the second engaging member 10B and the locking portion 25e by the coil 24 in the second lens holding assembly LH2.

Then, the control device CTR supplies current to the first coil 42A1 in the first coil set 42A and the second coil 42B2 in the second coil set 42B by PWM controlling the power supply CS.

When the first coil 42A1 receives a current supply from the power source CS, the magnetic force generated by the first coil 42A1 moves the first drive magnet 6A away, and the first lens body LS1 (first lens holder 3A) at the limit of movement on the X1 side shown in FIG. 13(B) can be moved to the position shown in FIG. 12(A).

When the second coil 42A2 receives a current supply from the power source CS, the magnetic force generated by the second coil 42A2 attracts the first drive magnet 6A, and the first lens body LS1 (first lens holder 3A) located in the position shown in FIG. 12(A) can be moved to the movement limit position on the X2 side shown in FIG. 13(A).

When the second coil 42A2 receives a current in the opposite direction from the power source CS, the magnetic force generated by the second coil 42A2 moves the first drive magnet 6A away, and the first lens body LS1 (first lens holder 3A) at the limit of movement on the X2 side shown in FIG. 13(A) can be moved to the position shown in FIG. 12(A).

When the first coil 42A1 receives a current supplied in the opposite direction from the power source CS, the magnetic force generated by the first coil 42A1 attracts the first drive magnet 6A, and the first lens body LS1 (first lens holder 3A) in the position shown in FIG. 12(A) can be moved to the movement limit position on the X1 side shown in FIG. 13(B).

Similarly, when the second coil 42B2 receives a current supply from the power source CS, the magnetic force generated by the second coil 42B2 moves the second drive magnet 6B away, and the second lens body LS2 (second lens holder 3B) at the limit of movement on the X2 side shown in FIG. 12(B) can be moved to the position shown in FIG. 12(A).

When the first coil 42B1 receives a current supply from the power source CS, the magnetic force generated by the first coil 42B1 attracts the second drive magnet 6B, and the second lens body LS2 (second lens holder 3B) located in the position shown in FIG. 12(A) can be moved to the movement limit position on the X1 side shown in FIG. 13(B).

When the first coil 42B1 receives a current in the opposite direction from the power source CS, the magnetic force generated by the first coil 42B1 moves the second drive magnet 6B away, and the second lens body LS2 (second lens holder 3B) at the limit of movement on the X1 side shown in FIG. 13(B) can be moved to the position shown in FIG. 12(A).

When the second coil 42B2 receives a current supplied in the opposite direction from the power source CS, the magnetic force generated by the second coil 42B2 attracts the second drive magnet 6B, and the second lens body LS2 (second lens holder 3B) in the position shown in FIG. 12(A) can be moved to the movement limit position on the X2 side shown in FIG. 12(B).

The control device CTR can identify the position of the first drive magnet 6A (first lens holder 3A) based on the outputs of the first hall element 43A1 to the third hall element 43A3 that constitute the first magnetic sensor set 43A. Therefore, when moving the first lens body LS1 (first lens holder 3A) in the optical axis direction, the control device CTR can feedback control the direction and magnitude of the current supplied to each of the first coil 42A1 and the second coil 42A2 that constitute the first coil set 42A based on the outputs of the first hall element 43A1 to the third hall element 43A3.

Similarly, the control device CTR can identify the position of the second drive magnet 6B (second lens holder 3B) based on the outputs of the first to third hall elements 43B1 to 43B3 that constitute the second magnetic sensor set 43B. Therefore, when moving the second lens body LS2 (second lens holder 3B) in the optical axis direction, the control device CTR can feedback control the direction and magnitude of the current supplied to each of the first coil 42B1 and the second coil 42B2 that constitute the second coil set 42B based on the outputs of the first to third hall elements 43B1 to 43B3.

Then, when the control device CTR receives a camera stop signal from the input device ID, it PWM controls the power supply CS to move the first lens body LS1 (first lens holder 3A) to the movement limit position on the X1 side, and move the second lens body LS2 (second lens holder 3B) to the movement limit position on the X2 side.

The camera stop signal is a signal for stopping the function of the camera mounted on the camera-equipped mobile device. In the example shown in FIG. 19, the camera stop signal is output by a touch panel serving as the input device ID when a software button for stopping the camera function displayed on a touch panel display mounted on the camera-equipped mobile device is touched.

After moving the first lens holder 3A to its movement limit position on the X1 side and moving the second lens holder 3B to its movement limit position on the X2 side, the control device CTR supplies a current to the coil 24 in the first lens holding assembly LH1 and the coil 24 in the second lens holding assembly LH2 in the opposite direction to when the camera activation signal was received.

The control device CTR can determine whether the first lens holder 3A (first drive magnet 6A) has reached the limit of movement on the X1 side based on the output of the first hall element 43A1, and can determine whether the second lens holder 3B (second drive magnet 6B) has reached the limit of movement on the X2 side based on the output of the third hall element 43B3.

When the coil 24 in the first lens holding assembly LH1 receives a current in the reverse direction from the power source CS, it moves the plunger 25 upward (in the Z1 direction) as shown in FIG. 18(B). That is, the coil 24 pushes the end face of the locking portion 25e of the plunger 25, which was located lower than the bottom surface of the first engaging member 10A as shown in FIG. 15(B2), to a position higher than the top surface of the first engaging member 10A as shown in FIG. 15(A2). This is to engage the first engaging member 10A with the locking portion 25e. This engagement prohibits the first lens holder 3A from moving in the optical axis direction. The same applies to the engagement of the second engaging member 10B and the locking portion 25e by the coil 24 in the second lens holding assembly LH2.

As described above, the lens holder driving device 101 according to one embodiment of the present invention includes a fixed member FM, a lens holder 3 capable of holding a lens body LS, a driving mechanism DM for moving the lens holder 3 in the optical axis direction, and a holding mechanism HM for holding the lens holder 3 at a movement limit position that is a position on the end side of the movable range in the optical axis direction. The holding mechanism HM includes a plunger 25 as a moving body provided on the fixed member FM and including a locking portion 25e that moves forward and backward in a direction intersecting the optical axis direction, an electromagnetic mechanism EM for moving the plunger 25 forward and backward, an engagement member 10 provided on a movable member MB including the lens holder 3 and having a notch CT as an engagement portion with which the locking portion 25e can engage, and a lock mechanism LK for holding the plunger 25 in a state in which the locking portion 25e and the notch CT are engaged at the movement limit position that is the position of the movement end of the lens holder 3 in the optical axis direction.

In this configuration, the lens holder driving device 101 holds the lens holder 3 at the movement limit position by realizing the engagement between the locking portion 25e of the plunger 25 and the notch CT of the engagement member 10, and allows the lens holder 3 to move in the optical axis direction by releasing this engagement. Therefore, the lens holder driving device 101 can reliably hold the lens holder 3 at the movement limit position. In addition, the lens holder driving device 101 can hold the lens holder 3 at the movement limit position without using the frictional force generated when a part of the fixed side member and a part of the movable side member are brought into frictional contact. Therefore, this configuration does not adversely affect the movement of the lens holder 3 when the engagement is released, and the force holding the lens holder 3 at the movement limit position does not change over time.

The plunger 25 may be configured to include a magnetic member. In this embodiment, the plunger 25 is formed of a magnetic material. As shown in FIG. 18(B), the locking mechanism LK may have an upper retaining magnet 22 as a first retaining magnet that attracts the magnetic member or the plunger 25 itself to retain the plunger 25 in the locked position. The locked position refers to the position of the plunger 25 when the engaging portion 25e of the plunger 25 and the notch CT of the engagement member 10 are engaged. The state in which the plunger 25 is in the locked position is referred to as the "locked state."

With this configuration, the lens holder driving device 101 does not need to continue driving the electromagnetic mechanism EM to hold the plunger 25 in the locked position. In other words, the lens holder driving device 101 can continue to hold the plunger 25 in the locked position even if the supply of current to the coil 24 in the lens holding assembly LH is stopped. Therefore, this configuration can reduce the power consumption of the lens holder driving device 101. However, the lens holder driving device 101 may maintain the locked state by continuing to supply current to the coil 24 in the lens holding assembly LH.

As shown in FIG. 18(A), the locking mechanism LK may also have a lower retaining magnet 26 as a second retaining magnet that attracts a magnetic member to retain the plunger 25 in the unlocked position. The unlocked position refers to the position of the plunger 25 when the engagement between the engaging portion 25e of the plunger 25 and the notch CT of the engagement member 10 is released. Any state other than the locked state, including the state in which the plunger 25 is in the unlocked position, is referred to as the "unlocked state."

With this configuration, the lens holder driving device 101 does not need to continue driving the electromagnetic mechanism EM to hold the plunger 25 in the unlocked position. In other words, the lens holder driving device 101 can continue to hold the plunger 25 in the unlocked position even when the supply of current to the coil 24 in the lens holding assembly LH is stopped. Therefore, this configuration can reduce the power consumption of the lens holder driving device 101. However, the lens holder driving device 101 may maintain the unlocked state by continuing to supply current to the coil 24 in the lens holding assembly LH.

The upper holding magnet 22 and the lower holding magnet 26 may be arranged facing each other with a plunger 25 as a magnetic member in between, as shown in FIG. 18. This configuration can prevent the lens holding assembly LH from becoming too large.

The plunger 25 as the moving body may be an iron core. In this case, as shown in FIG. 18, the electromagnetic mechanism EM may be configured to include the plunger 25 as the iron core, a bobbin 23 arranged on the outer periphery of the plunger 25, and a coil 24 held on the outer periphery of the bobbin 23. This configuration can reduce the cost of the lens holding assembly LH.

The locking mechanism LK has a coil spring 27 that biases the plunger 25 as a moving body toward the locked position, and the plunger 25 may be configured to compress the coil spring 27 in the unlocked position as shown in FIG. 18(A). This configuration can reliably prevent the plunger 25 from coming into contact with the lower holding magnet 26. This configuration can also promote the movement of the plunger 25 from the unlocked position to the locked position. This is because the plunger 25 is always biased upward by the coil spring 27 in the unlocked position. This configuration can also prevent the locked state from being erroneously released to the unlocked position when the camera-equipped mobile device equipped with the lens holder driving device 101 is subjected to an impact due to being dropped, etc. In the example shown in FIG. 18(B), the plunger 25 is always biased upward by the coil spring 27 even in the locked position. Specifically, in the state shown in FIG. 18(B), the coil spring 27 biases the plunger 25 upward with a restoring force that is greater than the force of attraction of the lower retaining magnet 26 that attracts the plunger 25 downward.

The bobbin 23 may be configured to have a stopper portion (step SP3) that contacts the plunger 25 as an iron core in the locked position. This configuration can reliably prevent contact between the plunger 25 and the upper holding magnet 22.

A yoke 21 constituting the electromagnetic mechanism EM may be arranged on the outside of the coil 24. This configuration can suppress leakage of the magnetic field (magnetic flux) generated by the electromagnetic mechanism EM.

The driving mechanism DM may be composed of a driving magnet 6 provided on one side of the lens holder 3, and a driving coil (a coil constituting the coil set 42) facing the driving magnet 6. The electromagnetic mechanism EM may be disposed so as to face the other side of the lens holder 3. In other words, the electromagnetic mechanism EM may be disposed away from the driving magnet 6.

For example, as shown in FIG. 12(A), the first drive mechanism DM1 may be composed of a first drive magnet 6A provided on a side SB1 (see FIG. 15(A1)) on the Y1 side of the first lens holder 3A capable of holding the first lens body LS1, and a first coil 42A1 and a second coil 42A2 facing the first drive magnet 6A. In this case, the electromagnetic mechanism EM in the first lens holding assembly LH1 may be disposed to face the side SB2 on the Y2 side of the first lens holder 3A, as shown in FIG. 15(A1).

Also, as shown in FIG. 12(A), the second drive mechanism DM2 may be composed of a second drive magnet 6B (see FIG. 5) provided on the Y2 side of the second lens holder 3B capable of holding the second lens body LS2, and a first coil 42B1 and a second coil 42B2 facing the second drive magnet 6B. In this case, the electromagnetic mechanism EM in the second lens holding assembly LH2 may be arranged to face the Y1 side of the second lens holder 3B.

This configuration can prevent interference between the magnetic field generated by the drive magnet 6 and the magnetic field generated by the electromagnetic mechanism EM. This is because the drive magnet 6 and the electromagnetic mechanism EM are configured not to be excessively close to each other.

As shown in Figures 3 and 4, the lens holder driving device 101 according to one embodiment of the present invention includes a fixed side member FM, a movable side member MB including a first lens holder 3A capable of holding a first lens body LS1 and a second lens holder 3B capable of holding a second lens body LS2 arranged to have the same optical axis JD as the first lens body LS1, a first driving mechanism DM1 that moves the first lens holder 3A in the optical axis direction, and a second driving mechanism DM2 that moves the second lens holder 3B in the optical axis direction.

The fixed member FM has a first coil assembly 4A (first substrate 41A) as a first surface and a second coil assembly 4B (second substrate 41B) as a second surface, which are arranged to face each other with the first lens holder 3A and the second lens holder 3B in between. As shown in FIG. 7, the first coil set 42A is provided in the first coil assembly 4A, and the second coil set 42B is provided in the second coil assembly 4B. As shown in FIG. 4, the first drive magnet 6A facing the first coil assembly 4A (first coil set 42A) is fixed to the first lens holder 3A. As shown in FIG. 5, the second drive magnet 6B facing the second coil assembly 4B (second coil set 42B) is fixed to the second lens holder 3B. The first drive magnet 6A and the first coil set 42A form the first drive mechanism DM1, and the second drive magnet 6B and the second coil set 42B form the second drive mechanism DM2.

This configuration, which can move the first lens holder 3A and the second lens holder 3B separately, can facilitate the miniaturization of the lens holder driving device 101 compared to a configuration that includes two rotary electric motors. This configuration also prevents the first driving mechanism DM1 and the second driving mechanism DM2 from magnetically interfering with each other. This is because the first driving mechanism DM1 and the second driving mechanism DM2 are arranged to sandwich the first lens holder 3A and the second lens holder 3B. In other words, the first driving mechanism DM1 and the second driving mechanism DM2 are arranged with a sufficient distance between them.

The first coil set 42A is composed of one or more coils, and the second coil set 42B is composed of one or more coils.

In this embodiment, as shown in FIG. 7, the first coil set 42A includes a first coil 42A1 and a second coil 42A2, and the second coil set 42B includes a first coil 42B1 and a second coil 42B2. As shown in FIG. 13(A), the width W5, which is the dimension of the first drive magnet 6A in the optical axis direction, is different from the width W7, which is the dimension of the first coil 42A1 that constitutes the first coil set 42A in the optical axis direction. The width W7 of the first coil 42A1 is the same as the width of the second coil 42A2.

Also, as shown in FIG. 13B, when the first lens holder 3A (first lens body LS1) is located at the X1 end, which is one end of the movable range of the movable-side member MB, the central axis M1, which is the central position in the optical axis direction of the first drive magnet 6A, is located away from the central axis L1, which is the central position in the optical axis direction of the first coil 42A1 that constitutes the first coil set 42A. In other words, the central axis M1 of the first drive magnet 6A and the central axis L1 of the first coil 42A1 do not coincide.

As shown in FIG. 13A, the width W6 of the second drive magnet 6B in the optical axis direction is different from the width W8 of the first coil 42B1 constituting the second coil set 42B in the optical axis direction. The width W8 of the first coil 42B1 is the same as the width of the second coil 42B2.

Also, as shown in FIG. 13A, when the second lens holder 3B (second lens body LS2) is located at the other end of the movable range of the movable member MB, that is, the end on the X2 side, the central axis M2, which is the central position in the optical axis direction of the second drive magnet 6B, is located away from the central axis L4, which is the central position in the optical axis direction of the second coil 42B2 that constitutes the second coil set 42B. In other words, the central axis M2 of the second drive magnet 6B and the central axis L4 of the second coil 42B2 do not coincide.

With this configuration, the lens holder driving device 101 can reliably move the first lens holder 3A backward (X2 direction) when a current is supplied to the first coil 42A1, even when the first lens holder 3A is located at the front end (X1 end) of the movable range, as shown in FIG. 13(B), for example. If the central axis L1 of the first driving magnet 6A and the central axis M1 of the first coil 42A1 are aligned, there is a risk that the repulsive force that tries to move the first driving magnet 6A forward (X1 direction) and the repulsive force that tries to move the first driving magnet 6A backward (X2 direction) will be balanced. However, this configuration is configured so that the central axis L1 and the central axis M1 do not match, specifically, the central axis L1 is positioned forward of the central axis M1, so that the force that tries to move the first driving magnet 6A forward and the force that tries to move it backward can be prevented from being balanced.

As shown in Figures 4 and 5, the width W3, which is the dimension of the first lens holder 3A in the optical axis direction, is greater than the width W4, which is the dimension of the second lens holder 3B in the optical axis direction. As shown in Figure 13(A), the width W5, which is the dimension of the first drive magnet 6A in the optical axis direction, is greater than the width W6, which is the dimension of the second drive magnet 6B in the optical axis direction. In the example shown in Figure 13, the height of the first drive magnet 6A is the same as the height of the second drive magnet 6B.

With this configuration, the first drive mechanism DM1 can generate sufficient thrust to move the first lens holder 3A even if the first lens holder 3A is larger than the second lens holder 3B, because the first drive magnet 6A is larger than the second drive magnet 6B.

As shown in FIG. 13A, the width W7 of the first coil 42A1 and the second coil 42A2 constituting the first coil set 42A in the optical axis direction is larger than the width W8 of the first coil 42B1 and the second coil 42B2 constituting the second coil set 42B in the optical axis direction. In the example shown in FIG. 13, the height H1 of the first coil 42A1 and the second coil 42A2 constituting the first coil set 42A is the same as the height H2 of the first coil 42B1 and the second coil 42B2 constituting the second coil set 42B.

With this configuration, the first drive mechanism DM1 can generate sufficient thrust to move the first lens holder 3A even if the first lens holder 3A is larger than the second lens holder 3B, because the first coil 42A1 and the second coil 42A2 are each larger than the first coil 42B1 and the second coil 42B2, respectively.

Essentially, the wider the drive magnet 6, the greater the distance between two adjacent coils in the optical axis direction can be, and therefore the fewer the number of coils required to achieve the desired amount of movement of the lens holder 3. Furthermore, reducing the number of coils results in reduced power consumption by the lens holder drive device 101.

On the other hand, if a large number of coils are required to achieve the desired amount of movement of the lens holder 3, the power consumption of the lens holder driving device 101 can be reduced by making each coil smaller and reducing the power consumption of each coil.

Also, as shown in FIG. 13(B), in the Y-axis direction, which is a direction perpendicular to the optical axis, the second coil 42A2 constituting the first coil set 42A and the second coil 42B2 constituting the second coil set 42B partially overlap.

Specifically, in the example shown in FIG. 13(B), the arrangement area of the first coil set 42A has a width W9, and the arrangement area of the second coil set 42B has a width W10. In the Y-axis direction, which is perpendicular to the optical axis, the arrangement areas of the first coil set 42A and the second coil set 42B partially overlap. The overlap width is indicated by width W11.

With this configuration, the lens holder driving device 101 can partially overlap the movable range of the first lens holder 3A and the movable range of the second lens holder 3B.

As shown in FIG. 7, preferably, the first coil assembly 4A as the first surface is provided with a plurality of coils (first coil 42A1 and second coil 42A2), and the second coil assembly 4B as the second surface is also provided with a plurality of coils (first coil 42B1 and second coil 42B2).

With this configuration, the lens holder driving device 101 can increase the amount of movement of the first lens holder 3A compared to when one coil is provided in the first coil assembly 4A. Similarly, the lens holder driving device 101 can increase the amount of movement of the second lens holder 3B compared to when one coil is provided in the second coil assembly 4B.

Also, as shown in FIG. 13(B), the first holding magnet 12A (front magnet 12A1) that attracts the first driving magnet 6A when the first lens holder 3A (first lens body LS1) is positioned at the X1 end, which is one end of the movable range of the movable member MB, may be provided on the coil holder 5 (see FIG. 6) as the fixed member FM.

Also, as shown in FIG. 13(A), the second holding magnet 12B (rear magnet 12B2) that attracts the second driving magnet 6B when the second lens holder 3B (second lens body LS2) is positioned at the other end of the movable range of the movable member MB, that is, the X2 end, may be provided on the coil holder 5 (see FIG. 6) as the fixed member FM.

With this configuration, the lens holder driving device 101 can use magnetic force to attract the lens holder 3 to the end of the movable range and hold the lens holder 3 at the end of the movable range.

As shown in Figures 4 and 5, the lens holder driving device 101 may have two grooves 5G (a first groove 5G1 and a second groove 5G2) that guide the movement of the movable member MB in the optical axis direction. Note that instead of the two grooves 5G, the lens holder driving device 101 may have one or more grooves, one or more guide rails, or one or more guide shafts.

With this configuration, the lens holder driving device 101 can smoothly move the lens holder 3 in the optical axis direction.

The fixed member FM may have a coil holder 5 as a base member BM having a groove 5G, and a cover member 1 fixed to the base member BM. The movable member MB may hold balls on the upper and lower sides, and the ball held on the upper side of the movable member MB may be biased against the ceiling surface of the cover member 1.

For example, as shown in FIG. 11A, the first lens carrier 30A of the first lens holder 3A constituting the movable member MB may be configured to hold a lower ball set 8 on the lower side and an upper ball set 9 on the upper side. The upper ball set 9 may be pressed against the ceiling surface of the cover member 1 by a first spring set 31A.

With this configuration, the lens holder driving device 101 can suppress frictional resistance when the lens holder 3 moves.

The above describes preferred embodiments of the present invention in detail. However, the present invention is not limited to the above-described embodiments. Various modifications and substitutions can 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 combined as appropriate, so long as there is no technical contradiction.

For example, in the above embodiment, the first lens holding assembly LH1 is configured to advance and retract the locking portion 25e in a direction parallel to the Z-axis, which is one of the directions perpendicular to the optical axis direction, as shown in FIG. 18. However, the first lens holding assembly LH1 may be configured to advance and retract the locking portion 25e in a direction parallel to the Y-axis. In this case, the central axis of the coil 24 in the first lens holding assembly LH1 may be arranged to be parallel to the Y-axis. Alternatively, the first lens holding assembly LH1 may be configured to advance and retract the locking portion 25e in a direction that is not perpendicular to the optical axis direction, for example, a direction inclined with respect to the optical axis direction, or a direction parallel to the optical axis direction. In this case, the engagement portion of the first engagement member 10A is formed to appropriately engage with the locking portion 25e. The same applies to the second lens holding assembly LH2.

In the above embodiment, the first coil 42A1 and the second coil 42A2 constituting the first coil set 42A have a coil axis, which is the winding center of the coil, parallel to the Y axis, but they may have a coil axis parallel to the optical axis JD. The same applies to the second coil set 42B.

1: Cover member 1s: Storage section 1A: Outer wall section 1A1: First side plate section 1A2: Second side plate section 1A3: Third side plate section 1A4: Fourth side plate section 1B: Upper surface section 2: Base plate 3: Lens holder 3A: First lens holder 3B: Second lens holder 4: Coil assembly 4A: First coil assembly 4B: Second coil assembly 5: Coil holder 5G: Groove 5G1: First groove 5G2: Second groove 6: Driving magnet 6A: First driving magnet 6B: Second driving magnet 7: Plate-shaped member 7A: First plate-shaped member 7B: Second plate-shaped member 8: Lower ball set 8A: First lower ball set 8A1: First ball 8A2: Second ball 8A3: Third ball 8A4: Fourth ball Description of the symbols 8B: Second lower ball set 8B1: First ball 8B2: Second ball 8B3: Third ball 8B4: Fourth ball 9: Upper ball set 9A: First upper ball set 9A1: First ball 9A2: Second ball 9A3: Third ball 9A4: Fourth ball 9B: Second upper ball set 9B1: First ball 9B2: Second ball 9B3: Third ball 9B4: Fourth ball 10: Engagement member 10A: First engagement member 10B: Second engagement member 12: Holding magnet 12A: First holding magnet 12A1: Front magnet 12A2: Rear magnet 12B: Second holding magnet 12B1: Front magnet 12B2: Rear magnet 20: Upper cover 20h, 20k: Opening 21: Yoke Reference Signs List 22: Upper retaining magnet 22A: First magnet 22B: Second magnet 23: Bobbin 23n: Narrowed portion 23p, 23q: Convex portion 24: Coil 25: Plunger 25e: Locking portion 25m: Main body 25s: Shoulder 26: Lower retaining magnet 26A: First magnet 26B: Second magnet 27: Coil spring 28: Lower cover 28h: Opening 30: Lens carrier 30A: First lens carrier 30B: Second lens carrier 31: Spring set 31A: First spring set 31A1: First coil spring 31A2: Second coil spring 31A3: Third coil spring 31A4: Fourth coil spring 31B: Second spring set 31B1: First coil spring 31B2: Second coil spring 31B3...Third coil spring 31B4...Fourth coil spring 32...Push bar set 32A...First push bar set 32A1...First push bar 32A2...Second push bar 32B...Second push bar set 32B1...First push bar 32B2...Second push bar 41...Substrate 41A...First substrate 41B...Second substrate 42...Coil set 42A...First coil set 42A1...First coil 42A2...Second coil 42B...Second coil set 42B1...First coil 42B2...Second coil 43...Magnetic sensor set 43A...First magnetic sensor set 43A1...First hall element 43A2...Second hall element 43A3...Third hall element 43B...Second magnetic sensor set 43B1...First hall element 43B2...Second Hall element 43B3...Third Hall element 101...Lens holder driving device AP...Opening AX...Protrusion AX1...First protrusion AX2...Second protrusion AX3...Third protrusion AX4...Fourth protrusion BL...Rising portion BM...Base member CM...Camera module CP...Connection portion CS...Power supply CT...Notch CTR...Control device CU...Notch CV...Cavity DM...Driving mechanism DM1...First driving mechanism DM2...Second driving mechanism EM...Electromagnetic mechanism FM...Fixed side member HL...Hole HL1...First hole HL2...Second hole HL3...Third hole HL4...Fourth hole HM...Holding mechanism HS...Housing ID...Input device IS...Imaging element JD...Optical axis LH...Lens holding assembly LH1: First lens holding assembly LH2: Second lens holding assembly LK: Locking mechanism LM: Lower member LS: Lens body LS1: First lens body LS2: Second lens body LT: Light MB: Movable member MR: Mirror PR: Convex part RS1-RS11: Concave part SL1, SL2: Slope SP1-SP3: Step part SYS: Control system

Claims (9)

A fixed member;
a movable member including a first lens holder capable of holding a first lens body, and a second lens holder capable of holding a second lens body arranged to have the same optical axis as the first lens body;
a first driving mechanism that moves the first lens holder in an optical axis direction;
a second driving mechanism for moving the second lens holder in an optical axis direction,
the fixed member has a first surface and a second surface that are provided to face each other with the first lens holder and the second lens holder interposed therebetween,
A plurality of first coils are provided on the first surface,
A second coil is provided on the second surface,
a first drive magnet facing the first coil is fixed to the first lens holder;
a second drive magnet facing the second coil is fixed to the second lens holder;
the first drive magnet and the first coil constitute the first drive mechanism,
the second drive magnet and the second coil constitute the second drive mechanism ,
the first drive magnet is configured to face one of the first coils in a direction perpendicular to the optical axis when located at a first position, and to face another of the first coils in a direction perpendicular to the optical axis when located at a second position different from the first position ;
4. A lens holder driving device comprising: a dimension of the first drive magnet in the optical axis direction is different from a dimension of the first coil in the optical axis direction,
when the first lens holder is located at one end of a movable range of the movable member, a center position of the first drive magnet in the optical axis direction is located away from a center position of the first coil in the optical axis direction,
a dimension of the second drive magnet in the optical axis direction is different from a dimension of the second coil in the optical axis direction,
when the second lens holder is located at the other end of the movable range of the movable member, a center position of the second drive magnet in the optical axis direction is located away from a center position of the second coil in the optical axis direction.
2. The lens holder driving device according to claim 1. a dimension of the first lens holder in the optical axis direction is larger than a dimension of the second lens holder in the optical axis direction;
A dimension of the first drive magnet in the optical axis direction is larger than a dimension of the second drive magnet in the optical axis direction.
3. The lens holder driving device according to claim 1 or 2. A dimension of the first coil in the optical axis direction is larger than a dimension of the second coil in the optical axis direction.
4. The lens holder driving device according to claim 3. The first coil and the second coil partially overlap in a direction perpendicular to the optical axis.
5. The lens holder driving device according to claim 1. A plurality of first coils are provided on the first surface,
A plurality of second coils are provided on the second surface.
6. The lens holder driving device according to claim 1. a first holding magnet is provided on the fixed member, the first holding magnet attracting the first driving magnet when the first lens holder is located at one end of the movable range of the movable member;
7. The lens holder driving device according to claim 1. the fixed-side member has two grooves for guiding the movement of the movable-side member in the optical axis direction;
8. The lens holder driving device according to claim 1. the fixed member includes a base member having the groove and a cover member fixed to the base member,
The movable member holds balls on the upper and lower sides,
The ball held on the upper side of the movable member is biased against the ceiling surface of the cover member.
9. The lens holder driving device according to claim 8.

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