CN115701558A - Optical unit - Google Patents

Abstract

The present invention provides an optical unit, comprising: a movable body having an optical module; a fixed body that rotatably holds the movable body; and a drive mechanism that rotates the movable body relative to the fixed body with a direction orthogonal to the optical axis of the optical module as an axial direction of rotation, wherein the drive coil and the drive magnet constituting the drive mechanism can be miniaturized in the axial direction of rotation of the movable body relative to the fixed body even if they are arranged so as to be opposed to each other in the axial direction of rotation of the movable body relative to the fixed body. In the optical unit, the thickness of a drive magnet (24) disposed outside an optical module (2) in the radial direction about the rotation center of a movable body (3) is smaller than the thickness of the optical module (2). The drive magnet (24) is disposed between one end of the optical module (2) in the Z direction and the other end of the optical module (2) in the Z direction, which is the axial direction of rotation of the movable body (3) relative to the fixed body.

Description

Optical unit

Technical Field

The present invention relates to an optical unit including a movable body having an optical module such as a camera module, and a fixed body rotatably holding the movable body.

Background

Conventionally, an optical unit with a shake correction function having a shake correction function for correcting a shake of an optical image is known (for example, see patent document 1). The optical unit with a shake correction function described in patent document 1 includes: a movable body holding the optical module; a fixed body holding the movable body; and a magnetic drive mechanism for rotating the movable body with respect to the fixed body. The magnetic drive mechanism includes a plate-shaped magnet and a coil facing the magnet in an optical axis direction of the optical module. The fixed body holds the movable body via a universal joint mechanism, and the movable body is capable of rotating in an axial direction in which an X-axis direction orthogonal to the optical axis direction is a rotation axis direction and in an axial direction in which a Y-axis direction orthogonal to the optical axis direction and the X-axis direction is a rotation axis direction with respect to the fixed body.

In the optical unit with a shake correction function described in patent document 1, for example, the facing surface of the magnet facing the coil is a convex curved surface, and the facing surface of the coil facing the magnet is a concave curved surface. Therefore, in the optical unit with shake correction function, even if the rotation angle of the movable body with respect to the fixed body is increased, the distance between the magnet and the coil can be kept constant, and as a result, even if the rotation angle of the movable body with respect to the fixed body is increased, a decrease in the driving force of the magnetic driving mechanism can be suppressed.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2016-99503

Disclosure of Invention

The inventors of the present application have developed an optical unit having: a movable body having an optical module such as a camera module; a fixed body that rotatably holds the movable body; and a drive mechanism that rotates the movable body with respect to the fixed body, with a direction orthogonal to the optical axis of the optical module as an axial direction of rotation. The inventors of the present application have studied that, in such an optical unit, even when the angle of rotation of the movable body with respect to the fixed body is increased, the distance between the drive coil and the drive magnet constituting the drive mechanism can be kept constant, and the reduction in the drive force of the drive mechanism can be suppressed, by arranging the drive coil and the drive magnet in opposition to each other in the axial direction of rotation of the movable body with respect to the fixed body.

On the other hand, since the optical unit is used by being mounted on a portable device such as a smartphone, for example, even if the driving coil and the driving magnet are arranged to face each other in the axial direction of the rotation of the movable body with respect to the fixed body, the optical unit is preferably small in the axial direction of the rotation of the movable body with respect to the fixed body.

Therefore, an object of the present invention is to provide an optical unit including: a movable body having an optical module; a fixed body that rotatably holds the movable body; and a drive mechanism that rotates the movable body relative to the fixed body with a direction orthogonal to the optical axis of the optical module as an axial direction of rotation, wherein the drive coil and the drive magnet constituting the drive mechanism can be miniaturized in the axial direction of rotation of the movable body relative to the fixed body even if they are arranged so as to be opposed to each other in the axial direction of rotation of the movable body relative to the fixed body.

In order to solve the above-described problems, an optical unit according to the present invention includes: a movable body having an optical module; a fixed body that rotatably holds the movable body; and a drive mechanism that rotates the movable body with respect to the fixed body, the drive mechanism having a first direction orthogonal to an optical axis of the optical module as an axial direction of rotation, the drive mechanism including: a drive coil wound in a hollow shape; and a driving magnet disposed opposite to the driving coil in the first direction, the driving coil and the driving magnet being disposed outside the optical module in a radial direction around a rotation center of the movable body, a thickness of the driving magnet in the first direction being thinner than a thickness of the optical module in the first direction, the driving magnet being disposed between one end of the optical module in the first direction and the other end of the optical module in the first direction.

In the optical unit of the present invention, the thickness of the driving magnet disposed outside the optical module in the radial direction around the rotation center of the movable body in the first direction is smaller than the thickness of the optical module in the first direction, and the driving magnet is disposed between one end of the optical module in the first direction and the other end of the optical module in the first direction. Therefore, in the present invention, even if the driving coil and the driving magnet are disposed to face each other in the first direction which is the axial direction of the rotation of the movable body with respect to the fixed body, the optical unit can be downsized in the first direction as compared with a case where the driving magnet protrudes outward in the first direction from the first direction end of the optical module.

Further, in the present invention, since the driving coil and the driving magnet are disposed so as to face each other in the first direction, the optical unit can be downsized in the radial direction around the rotation center of the movable body with respect to the stationary body, as compared with the case where the driving coil and the driving magnet are disposed so as to face each other in the radial direction around the rotation center of the movable body with respect to the stationary body.

In the present invention, for example, the driving coil and the driving magnet are arranged on both sides of the optical module in a radial direction around the rotation center of the movable body, the driving magnet is fixed to the movable body, the driving coil is fixed to the fixed body, and in a movable-side portion constituted by the movable body and the driving magnet, when an outer peripheral surface of a radially largest portion around the rotation center of the movable body is an outermost peripheral surface, an outer side surface of the driving magnet in the radial direction around the rotation center of the movable body is formed in a convex curved surface shape having an arc shape around the rotation center of the movable body as a curvature center when viewed from the first direction, and constitutes at least a part of the outermost peripheral surface. In this case, the outer surface of the driving magnet in the radial direction around the rotation center of the movable body forms at least a part of the outermost peripheral surface, and the driving magnet becomes larger in the radial direction around the rotation center of the movable body, so that the driving force of the driving mechanism can be increased.

In the present invention, for example, the driving coil is wound in the first direction as the axial direction of the winding, and the opposing surface of the driving magnet opposing the driving coil is polarized to two poles in the circumferential direction around the rotation center of the movable body.

In the present invention, it is preferable that the driving coil includes a pair of effective side portions arranged at intervals in a circumferential direction around a rotation center of the movable body, a first connecting side portion connecting outer end portions of the pair of effective side portions in a radial direction around the rotation center of the movable body to each other, and a second connecting side portion connecting inner end portions of the pair of effective side portions in the radial direction around the rotation center of the movable body to each other, and the pair of effective side portions extend from the first connecting side portion toward the rotation center side of the movable body so as to approach each other as they approach each other toward an inner side in the radial direction around the rotation center of the movable body. With this configuration, when a current is supplied to the driving coil, the driving force of the driving mechanism is likely to act in a circumferential direction around the rotation center of the movable body. Therefore, the driving force of the driving mechanism to the movable body can be increased.

In the present invention, for example, the driving coil may be wound in a direction perpendicular to the first direction as a winding axial direction, and an opposing surface of the driving magnet opposing the driving coil may be magnetized to be unipolar.

In the present invention, for example, the driving magnet is disposed only on one side of the driving coil in the first direction. In this case, the structure of the optical unit can be simplified. In the present invention, for example, the driving magnets may be disposed on both sides of the driving coil in the first direction. In this case, the driving force of the driving mechanism can be increased.

Effects of the invention

As described above, in the present invention, in an optical unit including a movable body having an optical module, a fixed body rotatably holding the movable body, and a drive mechanism rotating the movable body with respect to the fixed body with a direction orthogonal to an optical axis of the optical module as an axial direction of rotation, even if a drive coil and a drive magnet constituting the drive mechanism are arranged to be opposed to each other in the axial direction of rotation of the movable body with respect to the fixed body, the optical unit can be downsized in the axial direction of rotation of the movable body with respect to the fixed body.

Drawings

Fig. 1 is a perspective view of an optical unit according to an embodiment of the present invention.

Fig. 2 is an exploded perspective view of the optical unit shown in fig. 1.

Fig. 3 (a) is a plan view showing the movable body and the driving magnet shown in fig. 1, and fig. 3 (B) is a plan view showing the camera module, the first frame, and the driving coil shown in fig. 2.

Fig. 4 is a rear view of the movable body and the drive mechanism shown in fig. 1.

Fig. 5 is a diagram for explaining the structure of a drive mechanism according to another embodiment of the present invention, where (a) is a perspective view and (B) is a rear view.

Fig. 6 is a diagram for explaining the structure of a drive mechanism according to another embodiment of the present invention, where (a) is a perspective view and (B) is a rear view.

Fig. 7 is a diagram for explaining the structure of a drive mechanism according to another embodiment of the present invention, where (a) is a perspective view and (B) is a rear view.

Detailed Description

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

(integral Structure of optical Unit)

Fig. 1 is a perspective view of an optical unit 1 according to an embodiment of the present invention. Fig. 2 is an exploded perspective view of the optical unit 1 shown in fig. 1. Fig. 3 (a) is a plan view showing the movable body 3 and the driving magnet 24 shown in fig. 1, and fig. 3 (B) is a plan view showing the camera module 2, the first frame 10, and the driving coil 23 shown in fig. 2.

In the following description, as shown in fig. 1 and the like, three directions orthogonal to each other are defined as an X direction, a Y direction, and a Z direction, respectively, the X direction is defined as a left-right direction, the Y direction is defined as a front-back direction, and the Z direction is defined as a vertical direction. Further, one side in the left-right direction, that is, the X1 direction side in fig. 1 and the like is referred to as the "left" side, the opposite side, that is, the X2 direction side in fig. 1 and the like is referred to as the "right" side, one side in the front-rear direction, that is, the Y1 direction side in fig. 1 and the like is referred to as the "front" side, the opposite side, that is, the Y2 direction side in fig. 1 and the like is referred to as the "rear" side, one side in the up-down direction, that is, the Z1 direction side in fig. 1 and the like is referred to as the "up" side, and the opposite side, that is, the Z2 direction side in fig. 1 and the like is referred to as the "down" side.

The optical unit 1 of the present embodiment is a small and thin unit mounted on a portable device such as a smartphone, for example, and includes a camera module 2 having a lens for photographing and an imaging element. The optical unit 1 is formed in a flat substantially rectangular parallelepiped shape having a small thickness as a whole. The optical unit 1 includes: a movable body 3 having a camera module 2; a fixed body 4 (see fig. 1) that rotatably holds the movable body 3; a drive mechanism 5 for rotating the movable body 3 relative to the fixed body 4; two spherical beads 6 and 7 constituting a pivot of movable body 3 with respect to fixed body 4. The camera module 2 of the present embodiment is an optical module.

The optical axis L (see fig. 3B and the like) of the camera module 2 is orthogonal to the vertical direction. The movable body 3 is rotatable relative to the fixed body 4 in an axial direction in which the vertical direction orthogonal to the optical axis L of the camera module 2 is a rotational direction. That is, the movable body 3 is rotatable with respect to the fixed body 4 around an axis L1 (see fig. 3B and the like) having the vertical direction as the axial direction as the rotation center. The drive mechanism 5 rotates the movable body 3 relative to the fixed body 4 in the axial direction in which the vertical direction is rotational. For example, the driving mechanism 5 rotates the movable body 3 relative to the fixed body 4 to correct the shake of the optical unit 1 during shooting. Alternatively, the driving mechanism 5 rotates the movable body 3 relative to the fixed body 4 for panoramic photography, for example. The vertical direction (Z direction) of the present embodiment is a first direction orthogonal to the optical axis L of the camera module 2. The vertical direction is the thickness direction of the optical unit 1.

In the present embodiment, when the drive coil 23 described later, which constitutes a part of the drive mechanism 5, is in a non-energized state, the movable body 3 does not rotate with respect to the fixed body 4, and the movable body 3 is arranged at a predetermined origin position (reference position) with respect to the fixed body 4, the direction of the optical axis L (optical axis direction) of the camera module 2 coincides with the front-rear direction. The movable body 3 can rotate by about 10 ° in the clockwise direction in fig. 3 (hereinafter, this direction is referred to as "clockwise direction") and the counterclockwise direction in fig. 3 (hereinafter, this direction is referred to as "counterclockwise direction"), respectively, with reference to the origin position, for example. In the following description, a radial direction around the rotation center of movable body 3 with respect to fixed body 4 is referred to as a "radial direction", and a circumferential direction (circumferential direction) around the rotation center of movable body 3 with respect to fixed body 4 is referred to as a "circumferential direction".

Movable body 3 is formed in a flat rectangular parallelepiped shape having a small thickness in the vertical direction as a whole. The movable body 3 includes a frame 8 (see fig. 1) for fixing the camera module 2 and a magnetic plate 9 fixed to the frame 8, in addition to the camera module 2. The camera module 2 is formed in a flat rectangular parallelepiped shape having a small vertical thickness. The upper surface, the lower surface, the rear surface, and the side surfaces in the left-right direction of the camera module 2 are flat surfaces. The upper surface and the lower surface of the camera module 2 are orthogonal to the vertical direction. When the movable body 3 is disposed at the origin position, the lateral side of the camera module 2 in the left-right direction is orthogonal to the left-right direction, and the rear surface of the camera module 2 is orthogonal to the front-rear direction.

The frame 8 is composed of a first frame 10 covering the lateral and lower surfaces of the camera module 2 in the left-right direction, and a second frame 11 covering the upper surface of the camera module 2. The first frame 10 is formed by bending a thin metal plate into a predetermined shape. The first frame 10 has: two side surface portions 10a constituting lateral surfaces of the first frame 10 in the left-right direction; and a bottom surface portion 10b constituting a bottom surface of the first frame 10. The side surface portion 10a is formed in a rectangular flat plate shape. When the movable body 3 is disposed at the origin position, the thickness direction of the side surface portion 10a coincides with the left-right direction.

The bottom surface portion 10b is formed in a rectangular flat plate shape. The thickness direction of the bottom portion 10b coincides with the vertical direction. A through hole 10c penetrating the bottom surface portion 10b in the vertical direction is formed in the center portion of the bottom surface portion 10b. The through-hole 10c is formed in a circular hole shape. The beads 6 are disposed below the bottom surface portion 10b. The inner diameter of the through-hole 10c is smaller than the outer diameter of the bead 6. The upper end of the bead 6 is disposed in the through-hole 10c.

The second frame 11 is a thin flat metal plate. In addition, the second frame 11 is a magnetic plate formed of a magnetic material having magnetism. The thickness direction of the second frame 11 coincides with the vertical direction. The second frame 11 is fixed to the upper end of the first frame 10. The width of the second frame 11 in the left-right direction is wider than the width of the second frame 11 in the front-rear direction. The end surface 11a of the second frame 11 in the left-right direction is formed in a convex curved surface shape. The end surface 11a has an arc shape with the center of rotation of the movable body 3 as the center of curvature when viewed in the vertical direction. When movable body 3 is disposed at the origin position, front-rear direction end surface 11b of second frame 11 is orthogonal to the front-rear direction.

A through hole 11c penetrating the second frame 11 in the vertical direction is formed in the center of the second frame 11. The through-hole 11c is formed in a circular hole shape. The beads 7 are disposed on the upper side of the second frame 11. The inner diameter of the through-hole 11c is smaller than the outer diameter of the bead 7. The lower end of the bead 7 is disposed in the through-hole 11c. The through-hole 11c is arranged at the same position as the through-hole 10c in the horizontal direction, and the through-hole 11c overlaps the through-hole 10c when viewed in the vertical direction. That is, the beads 6 and 7 are arranged at the same position in the horizontal direction, and the beads 6 and 7 overlap when viewed from the vertical direction. The center of the bead 6 and the center of the bead 7 are arranged on the axis L1. In fig. 3 (a), the through-hole 11c of the second frame 11 is not shown.

The magnetic plate 9 is made of a magnetic material having magnetism. The magnetic plate 9 is formed in a rectangular flat plate shape having a thickness equal to that of the side surface portion 10a of the first frame 10. The magnetic plate 9 is fixed to the outer side surface of the side surface portion 10a in the left-right direction. When movable body 3 is disposed at the origin position, the thickness direction of magnetic plate 9 coincides with the left-right direction.

As described above, the camera module 2 includes the lens and the imaging element. The image pickup element is arranged on the rear end side of the camera module 2, and an object arranged on the front side of the camera module 2 is picked up by the camera module 2. The camera module 2 includes a circuit board 15 on which an image pickup device is mounted. The circuit board 15 constitutes a rear surface of the camera module 2. The camera module 2 of the present embodiment includes a magnetic drive mechanism for autofocusing.

A flexible printed circuit board (FPC) 16 is led out from the circuit substrate 15 constituting the rear surface of the camera module 2. The FPC16 is drawn out rearward from the center of the circuit board 15 in the left-right direction. In addition, the FPC16 is led out to the rear side from the center portion of the camera module 2 in the left-right direction, and is led out to the rear side from the center portion of the movable body 3 in the left-right direction. The FPC16 led out to the rear side from the circuit substrate 15 is then led around to the left side and then to the front side. The front end of the FPC16 is fixed to a housing 18 constituting the fixed body 4. The FPC16 is bent into a substantially rectangular groove shape (substantially U-shape).

The fixed body 4 includes: a housing 18 which constitutes the lateral side and the lower side of the fixed body 4 in the lateral direction; a cover 19 that constitutes an upper surface of the fixed body 4; and a fixed plate 20 and a magnetic plate 21 fixed to the case 18. The housing 18 is formed of a resin material. The case 18 is composed of two side surface portions 18a constituting lateral surfaces of the case 18 in the left-right direction and a bottom surface portion 18b constituting a lower surface of the case 18. Movable body 3 is disposed between two side surface portions 18a in the left-right direction. Movable body 3 is disposed above bottom surface 18b.

The inner surface of the side surface portion 18a in the radial direction is formed in a concave surface shape. The shape of the inner side surface as viewed in the vertical direction is an arc shape having the center of curvature as the center of rotation of movable body 3. Through holes 18c for arranging a driving coil 23 described later constituting a part of the driving mechanism 5 are formed in both ends of the bottom surface portion 18b in the left-right direction. The through hole 18c vertically penetrates the bottom surface 18b. An FPC fixing portion 18f protruding to the left is formed at the front end of the side surface portion 18a disposed on the left side. The front end of the FPC16 is fixed to the FPC fixing portion 18f by a double-sided tape or the like.

The fixing plate 20 is formed of a thin metal plate. The fixing plate 20 is formed in a substantially disk shape. The fixing plate 20 is fixed to the center of the upper surface of the bottom surface 18b. A ball arrangement portion 20a for arranging the lower end portion of the ball 6 is formed at the center of the fixed plate 20. The bead arrangement portion 20a is formed in a substantially hemispherical shape bulging downward, and the upper surface of the bead arrangement portion 20a is formed in a hemispherical concave curved surface recessed downward. The beads 6 are disposed above the bead disposition portion 20a.

The cover 19 is a thin flat metal plate. The cover 19 is fixed to the upper end of the housing 18. Movable body 3 is disposed below cover 19. A spring portion 19a for biasing the ball 7 is formed in the center of the cover 19. That is, the cover 19 is a plate spring. The spring portion 19a is slightly cut and raised toward the lower side. A bead arrangement portion 19b for arranging the upper end portion of the bead 7 is formed at the tip end portion of the spring portion 19a. The bead arrangement portion 19b is formed in a substantially hemispherical shape bulging upward, and the lower surface of the bead arrangement portion 19b is a hemispherical concave curved surface recessed upward. The beads 7 are disposed below the bead disposition portion 19b.

The spring portion 19a biases the ball 7 downward. The ball 7 is in contact with the lower surface of the ball placement portion 19b and the upper end edge of the through hole 11c of the second frame 11 at a predetermined contact pressure by the biasing force of the spring portion 19a. As described above, the beads 6 are arranged at the same positions as the beads 7 in the horizontal direction, and are brought into contact with the lower end edges of the through-holes 10c of the first frame 10 and the upper surface of the bead arrangement portion 20a at a predetermined contact pressure by the biasing force of the spring portions 19a. As described above, the movable body 3 can rotate relative to the fixed body 4 about the axis L1 passing through the centers of the beads 6 and 7.

The magnetic plate 21 is a thin metal flat plate. In addition, the magnetic plate 21 is formed of a magnetic material having magnetism. The thickness direction of the magnetic plate 21 coincides with the vertical direction. The magnetic plate 21 is fixed to the lower surface of the bottom surface portion 18b. The magnetic plate 21 is formed in the same shape as the second frame 11. When movable body 3 is disposed at the origin position, second frame 11 and magnetic plate 21 are disposed at the same position in the horizontal direction, and second frame 11 and magnetic plate 21 completely overlap when viewed in the vertical direction.

(Structure of drive mechanism)

Fig. 4 is a rear view of movable body 3 and drive mechanism 5 shown in fig. 1.

The drive mechanism 5 includes: a drive coil 23 wound in a hollow shape; and a driving magnet 24 disposed to face the driving coil 23 in the vertical direction. The driving coil 23 and the driving magnet 24 are arranged radially outside the camera module 2. In the present embodiment, the driving coil 23 and the driving magnet 24 are disposed radially on both sides of the camera module 2. Specifically, the driving coil 23 and the driving magnet 24 are disposed on both sides of the camera module 2 in the left-right direction, and sandwich the camera module 2 in the left-right direction. That is, the driving mechanism 5 includes two driving coils 23 and two driving magnets 24. Driving coil 23 and driving magnet 24 are disposed at a pitch of 180 ° with respect to the rotation center of movable body 3 with respect to fixed body 4.

The driving magnet 24 is formed in a block shape. The upper surface and the lower surface of the drive magnet 24 are planes perpendicular to the vertical direction. The inner surface of the drive magnet 24 in the right-left direction is a flat surface. When the movable body 3 is disposed at the origin position, the inner surface of the drive magnet 24 in the left-right direction is orthogonal to the left-right direction. The front and rear end faces 24b of the driving magnet 24 are flat. When the movable body 3 is disposed at the origin position, the end surface 24b of the drive magnet 24 is orthogonal to the front-rear direction.

The outer surface 24a of the driving magnet 24 in the left-right direction (i.e., the outer surface of the driving magnet 24 in the radial direction) is formed in a convex curved surface shape. That is, the outer surface 24a of the driving magnet 24 is a convex curved surface bulging outward in the left-right direction. The outer surface 24a has an arc shape with the center of rotation of the movable body 3 as the center of curvature when viewed in the vertical direction. The center angle of the outer surface 24a when viewed from the vertical direction is, for example, about 90 °. When the movable body 3 is disposed at the origin position, the two driving magnets 24 are disposed symmetrically with respect to the left and right.

The driving magnet 24 is fixed to the lower surface of the second frame 11. That is, the driving magnet 24 is fixed to the movable body 3. The width of the driving magnet 24 in the front-rear direction is equal to the width of the second frame 11 in the front-rear direction. The curvature radius of the outer surface 24a of the drive magnet 24, which is the arc-shaped convex curved surface, is equal to the curvature radius of the end surface 11a of the second frame 11, which is the arc-shaped convex curved surface. The driving magnet 24 is fixed to the lower surface of the second frame 11 such that the front-rear end surface 24b of the driving magnet 24 and the front-rear end surface 11b of the second frame 11 are aligned in the front-rear direction and the outer side surface 24a of the driving magnet 24 and the end surface 11a of the second frame 11 are aligned in the radial direction (see fig. 3 a).

In the movable portion 25 including the movable body 3 and the drive magnet 24 fixed to the movable body 3, if the outer peripheral surface of the radially largest portion is defined as the outermost peripheral surface 25a, the outer side surface 24a of the drive magnet 24 and the end surface 11a of the second frame 11 form the outermost peripheral surface 25a in the present embodiment. That is, the outer surface 24a of the driving magnet 24 constitutes a part of the outermost surface 25a. The magnetic plate 9 is disposed between the lateral side of the camera module 2 in the left-right direction and the drive magnet 24. The magnetic plate 9 functions as a magnetic shield for preventing magnetic interference between the magnetic drive mechanism for auto-focusing included in the camera module 2 and the drive mechanism 5.

The thickness (vertical thickness) of the driving magnet 24 is smaller than the thickness (vertical thickness) of the camera module 2. As shown in fig. 4, the upper surface of the driving magnet 24 is disposed below the upper surface of the camera module 2, and the lower surface of the driving magnet 24 is disposed above the lower surface of the camera module 2. That is, the driving magnet 24 is disposed between the upper surface of the camera module 2 and the lower surface of the camera module 2 in the vertical direction. That is, the driving magnet 24 is disposed between the upper end of the camera module 2, which is one end in the vertical direction of the camera module 2, and the lower end of the camera module 2, which is the other end in the vertical direction of the camera module 2, in the vertical direction, and falls within the height range of the camera module 2.

The lower surface of the driving magnet 24 is an opposing surface 24c that faces the driving coil 23. That is, in the present embodiment, the driving magnet 24 is disposed above the driving coil 23, and the driving magnet 24 is disposed only on one side of the driving coil 23 in the vertical direction. The opposing face 24c is magnetized to two poles in the circumferential direction. That is, the opposing surface 24c is magnetized so that the magnetic pole at one side portion of the opposing surface 24c in the circumferential direction and the magnetic pole at the other side portion of the opposing surface 24c in the circumferential direction are different magnetic poles, and is polarized to two poles in the circumferential direction. Specifically, the center of the driving magnet 24 in the front-rear direction when the movable body 3 is disposed at the origin position is a polarization position (magnetized polarization line) 24e, and the opposing surface 24c is polarized to two poles with the polarization position 24e as a boundary.

The driving coil 23 is an air-core coil formed by winding a wire into a hollow shape. The driving coil 23 is wound in the vertical direction as the axial direction of winding. As shown in fig. 3 (B), the driving coil 23 includes: a pair of (two) effective side portions 23a arranged at intervals in the circumferential direction; a first connecting edge portion 23b connecting outer end portions of the pair of effective edge portions 23a in the radial direction to each other; and a second connecting side portion 23c connecting radially inner end portions of the pair of effective side portions 23a to each other. The effective edge portion 23a is a portion contributing to the driving force of the driving mechanism 5.

The first connecting side 23b connects the outer ends of the pair of effective sides 23a in the left-right direction to each other. The second connecting side 23c connects the left and right inner ends of the pair of effective sides 23a. The first connecting side 23b and the second connecting side 23c are arranged in parallel with the front-rear direction. As shown in fig. 3 (B), the pair of effective side portions 23a extend from the first connecting side portion 23B toward the rotation center side of the movable body 3 so as to approach each other as they go radially inward. The length (length in the front-rear direction) of the second connecting side portion 23c is shorter than the length (length in the front-rear direction) of the first connecting side portion 23 b.

The driving coil 23 is mounted on a Flexible Printed Circuit (FPC) 26. Specifically, the lower end surface of the driving coil 23 is attached to the upper surface of the FPC 26. The two driving coils 23 are mounted on a common FPC 26. FPC26 is secured to the lower surface of housing 18. That is, the driving coil 23 is fixed to the fixed body 4 through the FPC 26. The lower end of the driving coil 23 is disposed in the through-hole 18c. The driving coil 23 and the FPC26 are disposed above the magnetic plate 21. When a current is supplied to driving coil 23, movable body 3 rotates with respect to fixed body 4 about axis L1 as the center of rotation.

In the present embodiment, even if movable body 3 rotates to the clockwise rotation end with respect to fixed body 4, polarization position 24e of driving magnet 24 does not reach effective side portion 23a arranged on the clockwise side in the circumferential direction. Even if movable body 3 rotates to the counterclockwise rotation end with respect to fixed body 4, polarization position 24e does not reach effective side portion 23a arranged on the counterclockwise side in the circumferential direction. That is, the interval between the pair of effective sides 23a in the circumferential direction is set so that the polarization position 24e does not reach the effective sides 23a over the entire range of rotation of the movable body 3.

(main effects of the present embodiment)

As described above, in the present embodiment, the thickness of the driving magnet 24 in the vertical direction is smaller than the thickness of the camera module 2 in the vertical direction, and the driving magnet 24 is disposed between the upper surface of the camera module 2 and the lower surface of the camera module 2 in the vertical direction. Therefore, in the present embodiment, even if the driving coil 23 and the driving magnet 24 are disposed to face each other in the vertical direction, the optical unit 1 can be downsized in the vertical direction as compared with a case where the driving magnet 24 protrudes outward in the vertical direction from the upper end or the lower end of the camera module 2. In addition, in the present embodiment, since the driving coil 23 and the driving magnet 24 are disposed to face each other in the vertical direction, the optical unit 1 can be downsized in the radial direction as compared with the case where the driving coil 23 and the driving magnet 24 are disposed to face each other in the radial direction.

In the present embodiment, the outer surface 24a of the driving magnet 24 in the radial direction constitutes a part of the outermost peripheral surface 25a of the movable body 3, and the driving magnet 24 is enlarged in the radial direction. Therefore, in the present embodiment, the driving force of the driving mechanism 5 can be increased. In the present embodiment, since the pair of effective side portions 23a of the driving coil 23 extend from the first connecting side portion 23b toward the rotation center side of the movable body 3 so as to approach each other as they go radially inward, the direction in which the driving force of the driving mechanism 5 acts is likely to go in the circumferential direction when the current is supplied to the driving coil 23. Therefore, in the present embodiment, the driving force of the driving mechanism 5 to the movable body 3 can be increased.

(modification 1 of drive mechanism)

Fig. 5 is a diagram for explaining the structure of a drive mechanism 5 according to another embodiment of the present invention, where (a) is a perspective view and (B) is a rear view. In fig. 5, the same components as those of the above embodiment are denoted by the same reference numerals.

In the above embodiment, as shown in fig. 5, the driving magnets 24 may be disposed on both sides in the vertical direction of the driving coil 23. In this case, magnetic plate 21 is fixed to the lower surface of bottom surface portion 10b of first frame 10, and magnetic plate 21 does not form part of fixed body 4 but forms part of movable body 3. A driving magnet 24 disposed below the driving coil 23 is fixed to the upper surface of the magnetic plate 21. The drive magnet 24 disposed above the drive coil 23 and the drive magnet 24 disposed below the drive coil 23 are disposed at the same position in the horizontal direction. In this modification, the lower surface of the driving magnet 24 disposed above the driving coil 23 and the upper surface of the driving magnet 24 disposed below the driving coil 23 form a facing surface 24c facing the driving coil 23.

The opposing face 24c is magnetized to two poles in the circumferential direction. The magnetic pole at the front portion of the opposing surface 24c of the driving magnet 24 disposed above the driving coil 23 (the magnetic pole at the one side of the opposing surface 24c in the circumferential direction) and the magnetic pole at the front portion of the opposing surface 24c of the driving magnet 24 disposed below the driving coil 23 (the magnetic pole at the one side of the opposing surface 24c in the circumferential direction) are different magnetic poles, and the magnetic pole at the rear portion of the opposing surface 24c of the driving magnet 24 disposed above the driving coil 23 (the magnetic pole at the other side of the opposing surface 24c in the circumferential direction) and the magnetic pole at the rear portion of the opposing surface 24c of the driving magnet 24 disposed below the driving coil 23 (the magnetic pole at the other side of the opposing surface 24c in the circumferential direction) are different magnetic poles.

The upper surface of the drive magnet 24 disposed above the drive coil 23 is disposed below the upper surface of the camera module 2. The lower surface of the driving magnet 24 disposed below the driving coil 23 is disposed at the same position in the vertical direction as the lower surface of the camera module 2. That is, the two driving magnets 24 are arranged between the upper surface of the camera module 2 and the lower surface of the camera module 2 in the vertical direction.

In this modification, a flat plate-shaped protective plate 28 is fixed to the FPC26 below the portion where the driving coil 23 is attached. The protection plate 28 is formed of a non-magnetic material. The protective plate 28 functions to prevent the FPC26 from being damaged by the contact between the driving magnet 24 disposed below the driving coil 23 and the FPC 26. No through-hole 18c is formed in the bottom surface portion 18b of the case 18, and a through-hole for disposing the driving coil 23 is formed in the side surface portion 18 a.

In this modification, since the driving magnets 24 are disposed on both sides of the driving coil 23 in the vertical direction, the driving force of the driving mechanism 5 can be increased. In addition, as in the above-described embodiment, when the driving magnet 24 is disposed only on one side of the driving coil 23 in the vertical direction, the configuration of the optical unit 1 can be simplified.

(modification 2 of drive mechanism)

Fig. 6 is a diagram for explaining the structure of a drive mechanism 5 according to another embodiment of the present invention, where (a) is a perspective view and (B) is a rear view. In fig. 6, the same components as those of the above embodiment are denoted by the same reference numerals.

In the above embodiment, the driving coil 23 is wound in the vertical direction as the axial direction of the winding, but the driving coil 23 may be wound in the direction perpendicular to the vertical direction (i.e., the horizontal direction) as the axial direction of the winding. For example, as shown in fig. 6, the driving coil 23 may be wound in the longitudinal direction as the winding axis direction. In the modification shown in fig. 6, the driving magnet 24 is disposed only above the driving coil 23.

In this modification, the opposing surface 24c of the driving magnet 24 opposing the driving coil 23 is magnetized to a single pole. In this modification, the magnetic member 30 made of a magnetic material is disposed on the inner peripheral side of the driving coil 23, and the fixed body 4 does not include the magnetic plate 21. In this modification, through-holes for disposing the driving coils 23 are formed in the side surface portion 18a and the bottom surface portion 18b of the case 18.

(modification of drive mechanism 3)

Fig. 7 is a diagram for explaining the structure of a drive mechanism 5 according to another embodiment of the present invention, where (a) is a perspective view and (B) is a rear view. In fig. 7, the same components as those of the above embodiment are denoted by the same reference numerals.

In the modification shown in fig. 6, as shown in fig. 7, the driving magnets 24 may be disposed on both sides in the vertical direction of the driving coil 23. In this case, as in the modification shown in fig. 5, a magnetic plate 21 is fixed to the lower surface of the bottom surface portion 10b of the first frame 10, and the magnetic plate 21 constitutes a part of the movable body 3. A driving magnet 24 disposed below the driving coil 23 is fixed to the upper surface of the magnetic plate 21. The drive magnet 24 disposed above the drive coil 23 and the drive magnet 24 disposed below the drive coil 23 are disposed at the same position in the horizontal direction.

In this modification, the lower surface of the driving magnet 24 disposed above the driving coil 23 and the upper surface of the driving magnet 24 disposed below the driving coil 23 form a facing surface 24c facing the driving coil 23. The opposing face 24c is magnetized to be unipolar. The magnetic pole of the opposing surface 24c of the driving magnet 24 disposed above the driving coil 23 is different from the magnetic pole of the opposing surface 24c of the driving magnet 24 disposed below the driving coil 23. In this modification, similarly to the modification shown in fig. 5, a protective plate 28 is fixed to the lower side of the portion of the FPC26 where the driving coil 23 is attached. A through hole for disposing the driving coil 23 is formed in the side surface portion 18a of the case 18.

(other embodiments)

The above-described embodiment and modification are examples of preferred embodiments of the present invention, but the present invention is not limited thereto, and various modifications can be made without changing the gist of the present invention.

In the above embodiment, a protective plate or protective tape for preventing damage to the driving coil 23 or the driving magnet 24 due to contact between the driving coil 23 and the driving magnet 24 may be attached to at least one of the opposing surface 24c of the driving magnet 24 and the upper surface of the driving coil 23. In this case, the protection plate or the protection tape is formed of a non-magnetic material. Similarly, in the modification shown in fig. 6, a protective plate or protective tape may be attached to at least one of the opposing surface 24c of the driving magnet 24 and the upper surface of the driving coil 23. In the modification shown in fig. 5 or the modification shown in fig. 7, a protective plate or a protective tape may be attached to at least one of the opposing surface 24c of the driving magnet 24 disposed above the driving coil 23 and the upper surface of the driving coil 23.

In the above embodiment, the curvature radius of the outer surface 24a of the driving magnet 24, which is the arc-shaped convex curved surface, may be larger than the curvature radius of the end surface 11a of the second frame 11, which is the arc-shaped convex curved surface, and the outermost peripheral surface 25a may be formed only by the outer surface 24a of the driving magnet 24. In the above embodiment, the radius of curvature of the outer surface 24a of the driving magnet 24 may be smaller than the radius of curvature of the end surface 11a of the second frame 11.

In the above embodiment, the driving coil 23 may be wound in a long circular shape, and the length of the first connecting side portion 23b may be equal to the length of the second connecting side portion 23c. In the above embodiment, the driving mechanism 5 may include only one driving coil 23 and one driving magnet 24, or may include three or more driving coils 23 and three or more driving magnets 24. In the above embodiment, the driving coil 23 may be fixed to the movable body 3, and the driving magnet 24 may be fixed to the fixed body 4. In the above embodiment, the optical unit 1 may include an optical module other than the camera module 2. For example, the optical unit 1 may include a laser module that emits laser light as the optical module. The optical unit 1 may include an optical module having an optical member such as a lens or a prism.

Description of the symbols

1. Optical unit

2. Cam module (optical module)

3. Movable body

4. Fixing body

5. Driving mechanism

23. Coil for driving

23a effective edge part

23b first connecting edge portion

23c second connecting edge portion

24. Magnet for driving

Outer side surface of 24a driving magnet

24c opposite side

25. Movable side part

25a outermost peripheral surface

L optical axis of camera module (optical axis of optical module)

Z first direction.

Claims (7)

1. An optical unit is characterized by comprising:

a movable body having an optical module;

a fixed body that rotatably holds the movable body; and

a drive mechanism configured to rotate the movable body with respect to the fixed body with a first direction orthogonal to an optical axis of the optical module as an axial direction of rotation,

the drive mechanism includes: a drive coil wound in a hollow shape; and a drive magnet disposed to face the drive coil in the first direction,

the driving coil and the driving magnet are disposed outside the optical module in a radial direction around a rotation center of the movable body,

the thickness of the driving magnet in the first direction is thinner than the thickness of the optical module in the first direction,

the driving magnet is disposed between one end of the optical module in the first direction and the other end of the optical module in the first direction.

2. An optical unit according to claim 1,

the driving coil and the driving magnet are disposed on both sides of the optical module in a radial direction around a rotation center of the movable body,

the driving magnet is fixed to the movable body,

the driving coil is fixed to the fixed body,

in the movable side portion comprising the movable body and the drive magnet, an outer peripheral surface of a radially largest portion around a rotation center of the movable body is an outermost peripheral surface,

an outer surface of the driving magnet in a radial direction around a rotation center of the movable body is formed in a convex curved surface shape, which is an arc shape having a curvature center around the rotation center of the movable body when viewed from the first direction, and constitutes at least a part of the outermost peripheral surface.

3. An optical unit according to claim 1 or 2,

the driving coil is wound in an axial direction of the winding in the first direction,

the opposing surface of the driving magnet opposing the driving coil is polarized to two poles in the circumferential direction around the rotation center of the movable body.

4. An optical unit according to claim 3,

the driving coil includes a pair of effective side portions arranged at intervals in a circumferential direction around a rotation center of the movable body, a first connecting side portion connecting outer end portions of the pair of effective side portions in a radial direction around the rotation center of the movable body, and a second connecting side portion connecting inner end portions of the pair of effective side portions in the radial direction around the rotation center of the movable body,

the pair of effective side portions extend from the first connecting side portion toward the rotation center side of the movable body so as to approach each other toward the inside in the radial direction centered on the rotation center of the movable body.

5. An optical unit according to claim 1 or 2,

the driving coil is wound in a direction orthogonal to the first direction as a winding axial direction,

the opposite surface of the driving magnet facing the driving coil is magnetized to be a single pole.

6. An optical unit according to any one of claims 1 to 5,

the driving magnet is disposed only on one side of the driving coil in the first direction.

7. An optical unit according to any one of claims 1 to 5,

the driving magnets are disposed on both sides of the driving coil in the first direction.

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