JP2024034078A - Optical element drive device, camera module, and camera mounting device - Google Patents

Abstract

To provide a highly reliable optical element drive device, a camera module, and a camera mounting device with which it is possible to stabilize movement motion of a movable part.SOLUTION: An optical element drive device comprises: a stationary unit; a movable unit that includes an optical element; a drive unit of an ultrasonic motor type that is located to an active-side member composed of one of the stationary unit and the movable unit, and that moves the movable unit to the stationary unit; and a power transmission unit that connects a passive-side member composed of the other of the stationary unit and the movable unit and the drive unit together, and that transmits motive force of the drive unit to the passive-side member. The drive unit includes a resonance unit having a pair of arms that vibrates, and the power transmission unit includes a passive member that is sandwiched while being urged by the pair of arms, and a connecting member that connects the passive member and the passive-side member together, the connecting member being elastically deformable.SELECTED DRAWING: Figure 10

Description

The present invention relates to an optical element driving device, a camera module, and a camera mounting device.

Generally, mobile terminals such as smartphones are equipped with a small camera module. Such camera modules have an autofocus function (hereinafter referred to as "AF function") that automatically adjusts the focus when photographing a subject, and an optical system that reduces shake (vibration) that occurs during shooting. An optical element driving device having an optical image stabilization (OIS) function (hereinafter referred to as "OIS function") that corrects and reduces image disturbance is applied (for example, Patent Document 1).

An optical element drive device having an AF function and an OIS function includes an autofocus drive unit (hereinafter referred to as "AF drive unit") for moving the lens part in the optical axis direction, and a plane perpendicular to the optical axis direction to move the lens part. and an image stabilization drive unit (hereinafter referred to as "OIS drive unit") for moving the camera within the camera. In Patent Document 1, an ultrasonic motor type drive unit is applied to the AF drive unit and the OIS drive unit.

The drive unit of the ultrasonic motor type includes an active element, a resonator. In an ultrasonic motor type drive unit, a resonant part is arranged in an active side member consisting of either a movable part or a fixed part, and a resonance part is arranged in an active side member consisting of either a movable part or a fixed part, and the resonance part is transmitted from the other of the movable part or the fixed part via a power transmission part which is a passive element. Power is transmitted to the passive side member. The resonance part and the power transmission part are in contact with each other in a biased state and slide against each other when driven. The "active member" is a member on which the drive unit is arranged, and the "passive member" is a member connected to the drive unit via the power transmission section.

International Publication No. 2015/123787

Generally, in an ultrasonic motor type drive unit, the active element, passive element, movable part, fixed part, etc. are designed so that the moving direction of the movable part matches the direction of power transmission. However, due to mounting tolerances and the like, a deviation may occur between the mounting angle of the passive element to the active element and the mounting angle of the movable part to the fixed part. This deviation also affects the contact state between the active element and the passive element, making it difficult for both members to slide, which may lead to unstable generation of power transmitted to the movable part.

An object of the present invention is to provide a highly reliable optical element drive device, camera module, and camera mounting device that can stabilize the movement of a movable part.

The optical element driving device according to the present invention includes:
a fixed part;
a movable part including an optical element;
an ultrasonic motor-type drive unit that is disposed on an active side member consisting of either the fixed part or the movable part and moves the movable part with respect to the fixed part;
a power transmission section that connects the driving section and a passive side member consisting of the other of the fixed section and the movable section, and transmits the power of the driving section to the passive side member;
Equipped with
The driving section has a resonating section having a pair of vibrating arms,
The power transmission section is
a passive member held between the pair of arms in a biased state;
a connecting member that connects the passive member and the passive side member,
The connecting member is elastically deformable.

The camera module according to the present invention includes:
The above optical element driving device,
an optical element attached to the movable part;
An imaging unit that captures a subject image formed by the optical element.

The camera-mounted device according to the present invention includes:
A camera-equipped device that is an information device or a transportation device,
The above camera module,
An image processing unit that processes image information obtained by the camera module.

According to the present invention, there is provided a highly reliable optical element drive device, camera module, and camera mounting device that can stabilize power transmission from an active element to a passive element and improve drive performance.

FIG. 1A and FIG. 1B are diagrams showing a smartphone equipped with a camera module according to an embodiment of the present invention. FIG. 2 is an external perspective view of the camera module. FIG. 3 is an external perspective view of the optical element driving device. FIG. 4 is an external perspective view of the optical element driving device. FIG. 5 is an exploded perspective view of the optical element driving device. FIG. 6 is an exploded perspective view of the optical element driving device. FIG. 7 is an exploded perspective view of the AF unit. FIG. 8 is an exploded perspective view of the AF unit. 9A and 9B are enlarged views of the OIS drive unit. 10A and 10B are schematic diagrams of the power transmission mechanism in the OIS drive unit. 11A and 11B are enlarged views of the AF drive unit. 12A and 12B are diagrams showing an automobile as a camera mounting device equipped with an on-vehicle camera module.

Hereinafter, embodiments of the present invention will be described in detail based on the drawings.

1A and 1B are diagrams showing a smartphone M (an example of a camera-equipped device) equipped with a camera module A according to an embodiment of the present invention. FIG. 1A is a front view of the smartphone M, and FIG. 1B is a rear view of the smartphone M.

Smartphone M has a dual camera consisting of two rear cameras OC1 and OC2. In this embodiment, camera module A is applied to rear cameras OC1 and OC2.

Camera module A is equipped with an AF function and an OIS function, and not only automatically focuses when photographing a subject, but also optically corrects shake (vibration) that occurs during photographing to photograph images without image blur. be able to.

FIG. 2 is an external perspective view of the camera module A. 3 and 4 are external perspective views of the optical element driving device 1 according to the embodiment. FIG. 4 shows a state in which FIG. 3 is rotated by 90 degrees around the Z axis. As shown in FIGS. 2 to 4, the embodiment will be described using an orthogonal coordinate system (X, Y, Z). The figures to be described later are also shown using a common orthogonal coordinate system (X, Y, Z).

For example, when the camera module A actually takes a picture with the smartphone M, the X-axis direction is the up-down direction (or the left-right direction), the Y-axis direction is the left-right direction (or the up-down direction), and the Z-axis direction is the front-back direction. It will be installed as follows. That is, the Z-axis direction is the optical axis direction, the upper side (+Z side) in the figure is the light receiving side in the optical axis direction, and the lower side (−Z side) is the imaging side in the optical axis direction. Further, the X-axis direction and the Y-axis direction orthogonal to the Z-axis are referred to as "optical axis orthogonal directions", and the XY plane is referred to as "optical axis orthogonal plane".

As shown in FIGS. 2 to 4, the camera module A includes an optical element drive device 1 that realizes an AF function and an OIS function, a lens section 2 in which a lens is housed in a cylindrical lens barrel, and a lens section 2. It includes an imaging unit 3 and the like that captures the captured image of the subject. That is, the optical element driving device 1 is a lens driving device that drives the lens section 2 as an optical element.

The imaging unit 3 is arranged on the imaging side of the optical element driving device 1 in the optical axis direction. The imaging unit 3 includes, for example, an image sensor board 301, an image sensor 302 mounted on the image sensor board 301, and a control unit 303. The image sensor 302 is configured by, for example, a CCD (charge-coupled device) type image sensor, a CMOS (complementary metal oxide semiconductor) type image sensor, or the like, and captures a subject image formed by the lens unit 2. The control unit 303 is composed of, for example, a control IC, and controls the drive of the optical element drive device 1 . The optical element driving device 1 is mounted on the image sensor substrate 301 and mechanically and electrically connected to it. Note that the control unit 303 may be provided on the image sensor board 301 or may be provided on a camera-equipped device (in the embodiment, the smartphone M) on which the camera module A is mounted.

The optical element driving device 1 is covered with a cover 24 on the outside. The cover 24 is a rectangular lidded square cylinder when viewed from above in the optical axis direction. In the embodiment, the cover 24 has a square shape in plan view. The cover 24 has a substantially circular opening 241 on the light receiving side surface (upper surface) in the optical axis direction. The lens portion 2 faces the outside through the opening 241 of the cover 24. The lens portion 2 may be arranged so as to protrude from the opening surface of the cover 24 toward the light receiving side. The cover 24 is fixed to the base 21 (see FIG. 5) of the OIS fixing section 20 of the optical element driving device 1, for example, by adhesive.

5 and 6 are exploded perspective views of the optical element driving device 1 according to the embodiment. 7 and 8 are exploded perspective views of the AF unit 10A. 6 and 8 respectively show the state in which FIG. 5 and FIG. 7 are rotated by 90 degrees around the Z axis.

As shown in FIGS. 5 to 8, the optical element driving device 1 according to the present embodiment includes an OIS movable section 10, an OIS fixed section 20, an X-axis direction drive unit 50X, a Y-axis direction drive unit 50Y, and an OIS support. It includes sections 41 and 42.

The OIS movable part 10 is a part that moves within a plane perpendicular to the optical axis during shake correction. The OIS movable section 10 includes an AF unit 10A and a second stage 13. The OIS fixed part 20 is a part to which the OIS movable part 10 is connected via the OIS support part 41.

The OIS movable part 10 is arranged apart from the OIS fixed part 20 in the optical axis direction, and is connected to the OIS fixed part 20 via the OIS support parts 41 and 42. The OIS movable section 10 and the OIS fixed section 20 are urged toward each other by an OIS urging member 30. The OIS biasing members 30 are arranged, for example, at the four corners of the optical element driving device 1 in a plan view.

The OIS biasing member 30 is composed of, for example, a tension coil spring, and connects the OIS movable part 10 and the OIS fixed part 20. In this embodiment, one end of the OIS biasing member 30 is connected to wiring (not shown) of the base 21, and the other end is connected to the terminal fitting 162 of the first stage 12. The OIS biasing member 30 functions as a power supply line to the AF drive unit 70 and the Y-axis direction drive unit 50Y.

The OIS biasing member 30 receives a tensile load when the OIS movable part 10 and the OIS fixed part 20 are connected, and acts so that the OIS movable part 10 and the OIS fixed part 20 approach each other. Thereby, the OIS movable part 10 is held movably within the XY plane while being biased in the optical axis direction (pressed against the base 21) by the OIS biasing member 30. Therefore, the OIS movable part 10 can be held in a stable state without rattling. Note that a damper material (not shown) that suppresses vibration may be disposed on the OIS biasing member 30.

The OIS support section 41 supports the second stage 13, which functions as the OIS movable section 10, with respect to the base 21, which functions as the OIS fixed section 20, while being spaced apart in the optical axis direction. In this embodiment, the OIS support section 41 is composed of four balls that are rotatably interposed between the base 21 and the second stage 13. Note that the number of balls forming the OIS support section 41 can be changed as appropriate.

The OIS support section 42 supports the first stage 12, which functions as the OIS movable section 10, with respect to the second stage 13, which functions as the OIS fixed section 20, while being spaced apart in the optical axis direction. In this embodiment, the OIS support section 42 is composed of four balls that are rotatably interposed between the second stage 13 and the first stage 12. Note that the number of balls forming the OIS support section 42 can be changed as appropriate.

In this embodiment, regarding movement in the X-axis direction, the entire OIS movable section 10 including the AF unit 10A moves as a movable body. On the other hand, regarding movement in the Y-axis direction, only the AF unit 10A moves as a movable body. That is, regarding movement in the Y-axis direction, the second stage 13 and the base 21 constitute the OIS fixing part 20.

The base 21 is formed of, for example, a molding material made of polyarylate (PAR), a PAR alloy (for example, PAR/PC) that is a mixture of a plurality of resin materials containing PAR, or a liquid crystal polymer. The base 21 is a rectangular member in plan view, and has a circular opening 211 in the center.

The base 21 has an OIS motor fixing part 212 on which the X-axis direction drive unit 50X is arranged. The OIS motor fixing part 212 is formed, for example, on one side of the outer peripheral edge of the base 21 along the X-axis so as to protrude toward the light receiving side in the optical axis direction, and has a shape capable of holding the X-axis direction drive unit 50X. There is. The base 21 functions as an active member regarding the movement of the OIS movable section 10 in the X-axis direction.

The base 21 supports the second stage 13 of the OIS movable section 10 via the OIS support section 41 so as to be movable in the X-axis direction. The base 21 has an OIS ball holding part 214 on the light receiving side surface in the optical axis direction, on which the OIS supporting part 41 is arranged. The OIS ball holding portion 214 is, for example, a groove having a rectangular shape extending in the X-axis direction in plan view. For example, the OIS ball holding portion 214 is formed to have a substantially V-shaped (tapered) cross-sectional shape so that the groove width becomes narrower toward the bottom side. In this embodiment, the OIS ball holding section 214 is provided near the four corners of the base 21, and the OIS movable section 10 (second stage 13) is is supported by 4 points.

A terminal fitting 22 and wiring (not shown) connected to the terminal fitting 22 are arranged on the base 21 by, for example, insert molding. The terminal fitting 22 is exposed from the base 21 and is electrically connected to the image sensor board 301. Further, the wiring is electrically connected to the OIS biasing member 30. Power is supplied to the AF drive unit 70 of the AF drive unit 70 and the Y-axis direction drive unit 50Y of the Y-axis direction drive unit 50Y via the OIS biasing member 30. Note that a sensor board may be placed on the base 21 and the wiring of the sensor board and the terminal fittings 22 may be electrically connected.

A position detection sensor that detects the position of the OIS movable part 10 in the X-axis direction and the Y-axis direction and the position of the AF movable part 11 in the Z-axis direction may be arranged on the base 21. For example, a magnetic sensor such as a Hall element or a TMR (Tunnel Magneto Resistance) sensor can be applied to the position detection sensor. In this case, magnets are arranged in the OIS movable section 10 (for example, the first stage 12) and the AF movable section 11 so as to face the magnetic sensor. Note that the position of the OIS movable section 10 in the X-axis direction and the Y-axis direction, and the position of the AF movable section 11 in the Z-axis direction may be detected by an optical sensor such as a photoreflector.

The second stage 13 is a member having a substantially rectangular shape when viewed in plan from the optical axis direction, and is made of, for example, a liquid crystal polymer. The second stage 13 has an opening 131 in a portion corresponding to the AF movable section 11.

In the second stage 13, a portion 132 corresponding to the X-axis direction drive unit 50X is formed to be recessed inward in the radial direction so that the X-axis direction drive unit 50X can be arranged without protruding outward in the radial direction. Furthermore, in the second stage 13, a portion 133 corresponding to the Y-axis direction drive unit 50Y is similarly formed to be recessed inward in the radial direction (hereinafter referred to as "OIS motor fixing portions 132, 133").

An X-axis direction power transmission section 60X is fixed to the OIS motor fixing section 132. A Y-axis direction power transmission section 60Y is fixed to the OIS motor fixing section 133. The second stage 13 functions as a passive member with respect to the movement of the OIS movable section 10 in the X-axis direction and the Y-axis direction.

The second stage 13 supports the first stage 12 of the AF unit 10A via the OIS support part 42 so as to be movable in the Y-axis direction. The second stage 13 has an OIS ball holding section 134 on the light receiving side surface (upper surface) in the optical axis direction, on which the OIS supporting section 42 is arranged. The OIS ball holding portion 134 is, for example, a groove having a rectangular shape extending in the Y-axis direction in plan view. For example, the OIS ball holding portion 134 has a substantially V-shaped (tapered) cross-sectional shape so that the groove width becomes narrower toward the bottom side. In this embodiment, the OIS ball holding section 134 is provided near the four corners of the second stage 13, and the four OIS supporting sections 42 arranged on the OIS ball holding section 134 support the AF unit 10A (the first stage 12 ) is supported by 4 points.

On the surface (lower surface) of the second stage 13 on the imaging side in the optical axis direction, there is a ball holding part (not shown) that holds the OIS support part 41 at a position facing the OIS ball holding part 214 of the base 21 in the Z-axis direction. ) is formed. The OIS support section 41 is held between the base 21 and the OIS ball holding section of the first stage 12 with multi-point contact. Therefore, the balls forming the OIS support portion 41 stably roll in the X-axis direction.

The AF unit 10A includes an AF movable section 11, a first stage 12, an AF drive unit 70, and an AF support section 15.

The first stage 12 is a member having a substantially rectangular shape when viewed in plan from the optical axis direction, and is made of, for example, a liquid crystal polymer. The first stage 12 has a substantially circular opening 121 in a portion corresponding to the AF movable section 11 .

In the first stage 12, a portion 122 corresponding to the X-axis direction drive unit 50X is formed to be recessed inward in the radial direction so that the X-axis direction drive unit 50X can be arranged without protruding outward in the radial direction. Furthermore, in the first stage 12, a portion 123 corresponding to the Y-axis direction drive unit 50Y is similarly formed to be recessed inward in the radial direction (hereinafter referred to as "OIS motor fixing portions 122, 123").

A Y-axis direction drive unit 50Y is fixed to the OIS motor fixing part 123. The first stage 12 functions as an active member regarding the movement of the OIS movable section 10 in the Y-axis direction.

The first stage 12 supports the AF movable section 11 via the AF support section 15 so as to be movable in the optical axis direction. The first stage 12 has an AF ball holding part 124 on the inner circumferential surface of the opening 121, in which the AF support part 15 is arranged. In this embodiment, the AF ball holding portions 124 are provided at two diagonally located locations among the four corners of the first stage 12 in plan view. The AF ball holding portion 124 extends along the optical axis direction, and has a substantially V-shaped (tapered) cross-sectional shape so that the groove width becomes narrower toward the groove bottom.

On the surface (lower surface) of the first stage 12 on the imaging side in the optical axis direction, there is an OIS ball holding part that holds the OIS support part 42 at a position facing the OIS ball holding part 134 of the second stage 13 in the Z-axis direction. (not shown) is formed. The OIS support part 42 is held between the OIS ball holding parts of the first stage 12 and the second stage 13 with multi-point contact. Therefore, the balls forming the OIS support portion 42 stably roll in the Y-axis direction.

The first stage 12 has an AF motor fixing part 125 on the inner peripheral surface of the opening 121, in which the AF drive unit 70 is disposed. The AF motor fixing portions 125 are provided, for example, at two diagonally located locations among the four corners of the first stage 12 in plan view. For example, an AF motor fixture 126 (see FIG. 11) is attached to the AF motor fixture 125, and the AF resonator 71 of the AF drive unit 70 is held by the AF motor fixture 126. The first stage 12 functions as an active member regarding the movement of the AF movable section 11 in the Z-axis direction.

A power supply line to the AF drive unit 70 and the Y-axis direction drive unit 50Y is arranged on the first stage 12. In this embodiment, four metal plates 161 are physically separated and arranged on the light-receiving side surface of the first stage 12 in the optical axis direction. The four metal plates 161 are respectively connected to terminal fittings 162 exposed from the four corners of the first stage 12. Power is supplied from wiring (not shown) of the base 21 to the AF drive unit 70 and the Y-axis direction drive unit 50Y via the OIS biasing member 30, the terminal fittings 162, and the metal plate 161.

The AF movable section 11 is a lens holder that holds the lens section 2 (see FIG. 2), and moves in the optical axis direction during focusing. The AF movable section 11 is arranged radially inwardly and spaced apart from the first stage 12 (AF fixed section), and is supported while being biased by the first stage 12 via the AF support section 15 .

The AF movable part 11 is formed of, for example, polyarylate (PAR), a PAR alloy obtained by mixing a plurality of resin materials including PAR, a liquid crystal polymer, or the like. The AF movable section 11 has a cylindrical lens housing section 111. The lens portion 2 is fixed to the inner circumferential surface of the lens housing portion 111 by, for example, adhesive.

The AF movable section 11 has an AF motor fixing section 112 on the outer peripheral surface of the lens housing section 111 at a position corresponding to the AF drive unit 70 to which the AF power transmission section 80 is fixed. The AF movable section 11 functions as a passive member regarding movement of the AF movable section 11 in the Z-axis direction.

The AF movable section 11 has an AF ball holding section 114 that holds the AF support section 15 on the outer circumferential surface of the lens housing section 111 at a position facing the AF ball holding section 124 of the first stage 12 in the radial direction. The AF support section 15 is held between the first stage 12 and the AF ball holding section of the AF movable section 11 with multi-point contact. Therefore, the balls forming the AF support section 15 stably roll in the Z-axis direction.

The AF support section 15 supports the AF movable section 11 in a radially spaced state with respect to the first stage 12 (AF fixed section). In this embodiment, the AF support section 15 is composed of four balls that are rotatably interposed between the first stage 12 and the AF movable section 11. Note that the number of balls constituting the AF support section 15 can be changed as appropriate.

The X-axis direction drive unit 50X and the Y-axis direction drive unit 50Y are ultrasonic motor type actuators that move the OIS movable section 10 in the X-axis direction and the Y-axis direction. As shown in FIG. 9A, the X-axis direction drive unit 50X is arranged on the base 21, which is an active side member, and is connected to the second stage 13, which is a passive side element, via the X-axis direction power transmission section 60X. . Further, as shown in FIG. 9B, the Y-axis direction drive unit 50Y is arranged on the first stage 12, which is an active side member, and is connected to the second stage 13, which is a passive side element, via the Y-axis direction power transmission section 60Y. is connected with. The X-axis direction drive unit 50X and the X-axis direction power transmission section 60X, and the Y-axis direction drive unit 50Y and the Y-axis direction power transmission section 60Y are arranged along mutually orthogonal sides.

The X-axis direction drive unit 50X and the X-axis direction power transmission section 60X are arranged to extend along the X-axis, and move the entire OIS movable section 10 in the X-axis direction. In this embodiment, the X-axis direction drive unit 50X is fixed to the OIS motor fixing part 212 of the base 21, and the X-axis direction power transmission part 60X is fixed to the OIS motor fixing part 132 of the second stage 13.

The Y-axis direction drive unit 50Y is arranged to extend along the Y-axis, and moves only the AF unit 10A of the OIS movable section 10 in the Y-axis direction. In this embodiment, the Y-axis direction drive unit 50Y is fixed to the OIS motor fixing part 123 of the first stage 12, and the Y-axis direction power transmission part 60Y is fixed to the OIS motor fixing part 133 of the second stage 13. .

In the following, the X-axis direction drive unit 50X and the Y-axis direction drive unit 50Y are collectively referred to as "OIS drive units 50X, 50Y." Furthermore, the X-axis direction power transmission section 60X and the Y-axis direction power transmission section 60Y are collectively referred to as "OIS power transmission sections 60X, 60Y."

The OIS drive units 50X and 50Y each have an OIS resonator 51 and an OIS piezoelectric element 52. The OIS power transmission sections 60X and 60Y each include a passive member 61 and a connecting member 62.

The OIS piezoelectric element 52 is, for example, a plate-shaped element made of a ceramic material, and generates vibration by applying a high frequency voltage. Two OIS piezoelectric elements 52 are arranged so as to sandwich the body (not shown) of the OIS resonator 51 .

The OIS resonator 51 is made of a conductive material, and resonates when the OIS piezoelectric element 52 vibrates. The OIS resonator 51 may be made of a metal having predetermined conductivity, shear strength, hardness, specific gravity, Young's modulus, etc., and is preferably made of stainless steel, for example.

The OIS resonator 51 and the OIS piezoelectric element 52 of the X-axis direction drive unit 50X are electrically connected to wiring (not shown) of the base 21. The OIS resonator 51 and the OIS piezoelectric element 52 of the Y-axis direction drive unit 50Y are electrically connected to a metal plate 161 that functions as a power supply line.

The OIS resonator 51 includes a substantially rectangular body (not shown) held between the OIS piezoelectric elements 52 and two arms 511 and 512 extending from the upper and lower parts of the body in the X-axis direction or the Y-axis direction. have The two arms 511 and 512 have a substantially symmetrical shape, and their respective free ends abut the passive members 61 of the OIS power transmission sections 60X and 60Y, resonate with the vibration of the OIS piezoelectric element 52, and move symmetrically. transform.

In this embodiment, the two arms 511 and 512 are formed so that the contact surfaces that contact the passive members 61 of the OIS power transmission sections 60X and 60Y face inward and face each other. When the OIS resonance section 51 resonates with the OIS power transmission sections 60X, 60Y (passive member 61) in contact with each other, the vibration motion of the OIS piezoelectric element 52 is caused by the vibration motion of the OIS power transmission sections 60X, 60Y. converted into linear motion.

The OIS resonator 51 has at least two resonant frequencies, and deforms with different behavior for each resonant frequency. In other words, the overall shape of the OIS resonant section 51 is set so that it deforms with different behaviors for two resonant frequencies. The different behaviors are a behavior in which the OIS power transmission units 60X and 60Y are moved forward in the X-axis direction or the Y-axis direction, and a behavior in which they are moved backward.

The passive member 61 is held between the arms 511 and 512 of the OIS resonator 51 while being biased. The passive member 61 is made of a rigid body and is less likely to deform than the arms 511 and 512. The passive member 61 is, for example, a block member made of a ceramic material such as zirconia. The passive member 61 may be a member in which a coating layer made of a ceramic material is formed on the surface of a block made of a metal material such as stainless steel (at least the surface that comes into contact with the OIS resonator 51).

Furthermore, the width of the passive member 61 in the direction in which it is held between the arms 511 and 512 is larger than the width of separation between the tips of the arms 511 and 512 (portions that come into contact with the passive member 61). When the passive member 61 is fitted between the arms 511 and 512, the arms 511 and 512 are deformed so as to be pushed apart, so that a restoring force is generated in the arms 511 and 512. The restoring force generated in the arms 511 and 512 holds the passive member 61 between the arms 511 and 512 in a biased state.

When the passive member 61 is composed of two plate-like members and the passive member 61 is urged against the arms 511 and 512 using the restoring force generated in the passive member 61, the passive member 61 and the arms 511 and 512 The contact state changes as the passive member 61 moves, and there is a possibility that the driving performance may become unstable. In contrast, in the present embodiment, the state of contact between the passive member 61 and the arms 511, 512 does not change even if the passive member 61 moves, so that stable driving performance can be obtained.

The connecting member 62 connects the passive member 61 and the second stage 13, which is a passive member. The connecting member 62 is made of a metal material such as stainless steel, for example. The connecting member 62 includes a fixed part 62 a fixed to the passive member 61 and an elastic part 62 b extending from the fixed part 62 a and coupled to the second stage 13 .

The elastic portion 62a is elastically deformable and is formed of, for example, a plate spring. The connecting member 62 is arranged such that the elastic portion 62a extends in the moving direction of the movable portion. The elastic portion 62a can be deformed (flexed) in the thickness direction, but is difficult to deform in the direction of movement of the movable portion. The elastic portion 62a absorbs a positional deviation between the moving direction D1 of the movable portion and the power transmission direction D2 that may occur due to mounting tolerances or the like.

Generally, in the optical element driving device 1, the active part is moved so that the moving direction D1 of the movable part (the relative moving direction of the second stage 13 with respect to the base 21 or the first stage 12) matches the power transmission direction D2. Elements (OIS resonance part 51), passive elements (OIS power transmission parts 60X, 60Y), etc. are designed. However, due to mounting tolerances and the like, for example, a deviation may occur between the mounting angle of the passive element to the active element and the mounting angle of the movable part to the fixed part. In this case, if the OIS power transmission parts 60X and 60Y are formed of rigid bodies, the power transmission direction D2 is inclined with respect to the moving direction D1 of the movable part, and the OIS resonance part 51 and the OIS power transmission part 60X , 60Y become difficult to slide. As a result, the generation of power transmitted to the movable part may become unstable (see FIG. 10B).

In contrast, in the present embodiment, the OIS drive units 50X and 50Y arranged on the base 21 and the first stage 12, which are active side members, and the second stage 13, which is a passive side member, are connected to the connecting member 62. They are connected via OIS power transmission sections 60X and 60Y. As a result, even if a positional deviation occurs between the mounting angle of the passive element to the active element and the mounting angle of the movable part to the fixed part, the positional deviation is absorbed by the elastic part 62a of the connecting member 62, so that the movable part can move. The direction D1 and the power transmission direction D2 match (see FIG. 10A). Therefore, the sliding movement between the OIS resonance part 51 and the OIS power transmission parts 60X, 60Y is maintained, the rolling motion of the balls of the OIS support parts 41, 42 is performed smoothly, and the moving operation of the movable part is stabilized.

The AF drive unit 70 is an ultrasonic motor type actuator that moves the AF movable section 11 in the Z-axis direction. As shown in FIGS. 11A and 11B, the AF drive unit 70 is arranged on the first stage 12, which is an active side member, and is connected to the AF movable section 11, which is a passive element, via the AF power transmission section 80. . FIG. 11A shows a state in which the AF drive unit 70 is attached to the AF movable section 11.

In this embodiment, two AF drive units 70 are arranged between the AF movable section 11 and the first stage 12. The AF drive unit 70 is fixed to the AF motor fixing part 125 of the first stage 12 so that arms 711 and 712 extend in the Z-axis direction.

The AF drive unit 70 includes an AF resonance section 71 and an AF piezoelectric element 72. The AF power transmission section 80 includes two AF plates 81 having a predetermined length in the optical axis direction.

The AF piezoelectric element 72 is, for example, a plate-shaped element made of a ceramic material, and generates vibration by applying a high frequency voltage. Two AF piezoelectric elements 72 are arranged so as to sandwich the body (not shown) of the AF resonator 71 .

The AF resonator 71 is formed of a conductive material and resonates upon receiving the vibration of the AF piezoelectric element 72. The AF resonator 71 may be made of metal having predetermined conductivity, shear strength, hardness, specific gravity, Young's modulus, etc. For example, like the OIS resonator 51, stainless steel is suitable.

The AF resonator 71 and the AF piezoelectric element 72 are electrically connected to a metal plate 161 that functions as a power supply line.

The AF resonator 71 has a substantially rectangular body (not shown) held between the AF piezoelectric elements 72 and two arms 711 and 712 extending from the body in the Z-axis direction. The two arms 711 and 712 have a substantially symmetrical shape, and their respective free ends abut against the AF plate 81 of the AF power transmission unit 80, and are deformed symmetrically by resonating with the vibration of the AF piezoelectric element 72. .

In this embodiment, the two arms 711 and 712 are formed so that the surfaces that contact the AF plate 81 face outward, and are arranged so that their free ends are sandwiched between the AF plate 81. When the AF resonance part 71 resonates when the AF resonance part 71 and the AF power transmission part 80 (AF plate 81) are in contact with each other, the vibration motion of the AF piezoelectric element 72 is converted into the linear motion of the AF power transmission part 80. be done.

Like the OIS resonance section 51, the AF resonance section 71 has at least two resonance frequencies, and deforms with different behavior for each resonance frequency. In other words, the overall shape of the AF resonance section 71 is set so that it deforms with different behaviors for two resonance frequencies.

The AF plate 81 is a hard plate-like member made of a metal material such as titanium copper, nickel copper, or stainless steel. The AF plate 81 is arranged on the AF motor fixing part 112 of the AF movable part 11 along the moving direction so as to come into contact with the arms 711 and 712 of the AF resonating part 71 . The AF plate 81 is fixed to the AF movable section 11 and is movable integrally with the AF movable section 11.

The AF plate 81 is interposed between the biasing member 82 disposed on the AF motor fixed part 112 of the AF movable part 11 and the AF resonance part 71. The AF plate 81 is held in a biased state toward the arms 711 and 712 of the AF resonator 71 by the biasing member 82 . Note that the biasing member 82 may be composed of, for example, a plate spring, or may be made of an elastic body such as a coil spring or hard rubber.

In the optical element drive device 1, when a voltage is applied to the AF drive unit 70, the AF piezoelectric element 72 vibrates, and the AF resonant section 71 deforms in a manner that corresponds to the frequency. The AF power transmission section 80 is slid in the Z-axis direction by the driving force of the AF drive unit 70. Along with this, the AF movable section 11 moves in the Z-axis direction, and focusing is performed. Since the AF support part 15 is made of a ball, the AF movable part 11 can move smoothly in the Z-axis direction. Furthermore, since the AF drive unit 70 and the AF power transmission section 80 are only in contact with each other in a biased state, the height of the optical element drive device 1 can be reduced by simply increasing the size of the contact portion in the Z-axis direction. The movement stroke of the AF movable section 11 can be easily lengthened without damage.

In the optical element drive device 1, when a voltage is applied to the OIS drive units 50X and 50Y, the OIS piezoelectric element 52 vibrates, and the OIS resonator 51 deforms in a manner that corresponds to the frequency. The OIS power transmission sections 60X, 60Y are slid in the X-axis direction or the Y-axis direction by the driving force of the OIS drive units 50X, 50Y. Along with this, the OIS movable section 10 moves in the X-axis direction or the Y-axis direction, and shake correction is performed. Since the OIS support parts 41 and 42 are formed of balls, the OIS movable part 10 can move smoothly in the X-axis direction or the Y-axis direction.

Specifically, when the X-axis direction drive unit 50X is driven and the X-axis direction power transmission section 60X moves in the X-axis direction, from the base 21 where the X-axis direction drive unit 50X is arranged to the second stage 13. Power is transmitted. At this time, since the OIS support part 42 held between the first stage 12 and the second stage 13 cannot roll in the X-axis direction, the position of the first stage 12 in the X-axis direction with respect to the second stage 13 is maintained. be done. On the other hand, since the OIS support portion 41 held between the second stage 13 and the base 21 can roll in the X-axis direction, the second stage 13 moves in the X-axis direction with respect to the base 21. The first stage 12 also follows the second stage 13 and moves in the X-axis direction.

Further, when the Y-axis direction drive unit 50Y is driven and the Y-axis direction power transmission section 60Y moves in the Y-axis direction, the power is transferred from the first stage 12 where the Y-axis direction drive unit 50Y is disposed to the second stage 13. is transmitted. At this time, since the OIS support part 41 held between the second stage 13 and the base 21 cannot roll in the Y-axis direction, the position of the second stage 13 in the X-axis direction with respect to the base 21 is maintained. On the other hand, since the OIS support part 42 held between the first stage 12 and the second stage 13 can roll in the Y-axis direction, the first stage 12 moves in the Y-axis direction with respect to the second stage 13. It turns out.

In the optical element drive device 1, for example, the X-axis direction drive unit is operated based on a detection signal indicating angular shake from a shake detection section (for example, a gyro sensor, not shown) so that the angular shake of the camera module A is canceled out. The voltage applied to the drive unit 50X and Y-axis direction drive unit 50Y is controlled. At this time, the translational movement of the OIS movable section 10 may be controlled by feeding back the detection result of the position detection section.

As described above, the optical element driving device 1 according to the embodiment has the following features singly or in appropriate combinations.

That is, regarding the movement of the OIS movable part 10 in the X-axis direction, the optical element driving device 1 includes a base 21 (fixed part), a second stage 13 (movable part) including the lens part 2 (optical element), and a base 21 (an active side member consisting of either a fixed part or a movable part) and an ultrasonic motor-type X-axis direction drive unit 50X (drive part) that moves the second stage 13 with respect to the base 21; , the second stage 13 (passive side member consisting of the other of a fixed part and a movable part) and the X-axis direction drive unit 50X are connected, and the power of the X-axis direction drive unit 50X is transmitted to the second stage 13. An X-axis direction power transmission section 60X is provided. The X-axis direction drive unit 50X has an OIS resonance section 51 having a pair of vibrating arms 511 and 512, and the X-axis direction power transmission section 60X is held between the two arms 511 and 512 while being biased. The connecting member 62 includes a passive member 61 that connects the passive member 61 and the second stage 13, and the connecting member 62 is elastically deformable. As a result, even if a positional deviation occurs between the mounting angle of the passive element to the active element and the mounting angle of the movable part to the fixed part, the positional deviation is absorbed by the connecting member 62, so that the second stage 13 which is the movable part The moving direction D1 of the power matches the moving direction D2 of the power (see FIG. 10A). Therefore, the sliding movement between the OIS resonance part 51 and the OIS power transmission parts 60X and 60Y is maintained, and the movement operation of the OIS movable part 10 including the second stage 13 in the X-axis direction with respect to the OIS fixed part 20 including the base 21 is maintained. is stabilized, drive performance can be improved, and the reliability of the optical element drive device 1, camera module A, and smartphone M (camera-equipped device) is improved.

Regarding the movement of the OIS movable part 10 in the Y-axis direction, the optical element driving device 1 includes a second stage 13 (fixed part), a first stage 12 (movable part) including the lens part 2 (optical element), An ultrasonic motor-type Y-axis direction drive unit that is disposed on the first stage 12 (active side member consisting of either a fixed part or a movable part) and moves the first stage 12 with respect to the second stage 13 50Y (driving section), the second stage 13 (passive side member consisting of the other of a fixed section and a movable section), and the Y-axis direction drive unit 50Y, and the power of the Y-axis direction drive unit 50Y is connected. A Y-axis direction power transmission section 60Y that transmits to the second stage 13 is provided. The Y-axis direction drive unit 50Y has an OIS resonance section 51 having a pair of vibrating arms 511 and 512, and the Y-axis direction power transmission section 60Y is held between the pair of arms 511 and 512 while being biased. The connecting member 62 includes a passive member 61 that connects the passive member 61 and the second stage 13, and the connecting member 62 is elastically deformable. As a result, even if a positional deviation occurs between the mounting angle of the passive element to the active element and the mounting angle of the movable part to the fixed part, the positional deviation is absorbed by the connecting member 62. The moving direction D1 of the power matches the moving direction D2 of the power (see FIG. 10A). Therefore, the sliding movement between the OIS resonance part 51 and the OIS power transmission parts 60X and 60Y is maintained, and the OIS movable part 10 including the first stage 12 is moved in the Y-axis direction with respect to the OIS fixed part 20 including the second stage 13. The moving operation is stabilized, driving performance can be improved, and the reliability of the optical element driving device 1, camera module A, and smartphone M (camera-equipped device) is improved.

The connecting member 62 is made of a metal material. Thereby, it is possible to easily absorb a positional deviation between the attachment angle of the passive element to the active element and the attachment angle of the movable part to the fixed part.

The connecting member 62 of the X-axis direction power transmission unit 60X includes a fixed part 61a fixed to the passive member 61, and an elastic part 62a extending from the fixed part 61a and connected to the second stage 13 (movable part). The elastic portion 62a is arranged so as to extend in the X-axis direction (the moving direction of the movable portion). As a result, elastic deformation of the elastic portion 62b in the X-axis direction is reduced, so power transmission in the X-axis direction from the X-axis drive unit 50X to the second stage 13 is not impaired, and appropriate drive performance is ensured. can do.

The connecting member 62 of the Y-axis direction power transmission unit 60Y includes a fixed part 61a fixed to the passive member 61, and an elastic part 62a extending from the fixed part 61a and connected to the first stage 12 (movable part). The elastic portion 62a is arranged so as to extend in the Y-axis direction (the moving direction of the movable portion). This reduces elastic deformation of the elastic portion 62b in the Y-axis direction, so transmission of power in the Y-axis direction from the Y-axis drive unit 50Y to the second stage 13 is not impaired, ensuring appropriate drive performance. can do.

Regarding the movement of the OIS movable part 10 in the X-axis direction, the base 21 (active side member) and the second stage 13 (passive side member) are supported by an OIS support part 41 (ball) so as to be relatively movable. . Regarding the movement of the OIS movable part 10 in the Y-axis direction, the first stage 12 (active side member) and the second stage 13 (passive side member) are directed to be relatively movable by the OIS support part 42 (ball). ing. Thereby, the OIS movable section 10 can be smoothly moved by utilizing the rolling motion of the ball.

In the X-axis direction power transmission section 60X and the Y-axis direction power transmission section 60Y, the passive member 62 is less likely to deform than the pair of arms 511, 512, and the passive member 62 in the direction sandwiched by the pair of arms 511, 512. The width is larger than the separation width between the pair of arms 511 and 512. Thereby, the state of contact between the passive member 62 and the arms 511, 512 is maintained even if the passive member 62 moves. The driving performance is improved compared to a case where the passive member 62 is composed of two plate-like members and the restoring force generated in the passive member 62 is used to urge the arms 511 and 512.

As above, the invention made by the present inventor has been specifically explained based on the embodiments, but the present invention is not limited to the above embodiments, and can be modified without departing from the gist thereof.

For example, in the embodiment, the power transmission structure characteristic of the present invention is applied to the X-axis direction drive unit 50X and the Y-axis direction drive unit 50Y, but it may also be applied to the AF drive unit 70. It may be applied only to either the X-axis direction drive unit 50X or the Y-axis direction drive unit 50Y.

Further, in the embodiment, the X-axis direction drive unit 50X, the Y-axis direction drive unit 50Y, and the AF drive unit 70 are all configured with ultrasonic motor type actuators, but the power transmission characteristic of the present invention is The drive unit to which this structure is not applicable does not need to be of the ultrasonic motor type.

Further, in the embodiment, the optical element driving device 1 having the AF function and the OIS function has been described as an example, but the present invention is applicable to an optical element driving device having one of the AF function and the OIS function. You can also.

In the embodiment, the smartphone M, which is a camera-equipped mobile terminal, has been described as an example of a camera-equipped device equipped with a camera module A. However, the present invention provides a camera module that processes image information obtained by the camera module. It can be applied to a camera-equipped device having an image processing section. Camera-equipped devices include information equipment and transportation equipment. Information devices include, for example, a camera-equipped mobile phone, a notebook computer, a tablet terminal, a portable game machine, a web camera, and a camera-equipped vehicle-mounted device (for example, a back monitor device, a drive recorder device). Furthermore, transportation equipment includes, for example, automobiles and drones (unmanned aerial vehicles).

12A and 12B are diagrams showing an automobile V as a camera mounting device on which a vehicle camera module VC (Vehicle Camera) is mounted. 12A is a front view of the automobile V, and FIG. 12B is a rear perspective view of the automobile V. The automobile V is equipped with the camera module A described in the embodiment as the in-vehicle camera module VC. As shown in FIGS. 12A and 12B, the in-vehicle camera module VC is attached, for example, to a windshield facing forward, or to a rear gate facing rearward. This in-vehicle camera module VC is used for back monitors, drive recorders, collision avoidance control, automatic driving control, and the like.

Further, in the embodiment, the optical element driving device 1 that drives the lens unit 2 as an optical element has been described, but the optical element to be driven may be an optical element other than a lens, such as a mirror or a prism.

The embodiments disclosed this time should be considered to be illustrative in all respects and not restrictive. The scope of the present invention is indicated by the claims rather than the above description, and it is intended that all changes within the meaning and range equivalent to the claims are included.

1 Optical element drive device 10 OIS movable part (movable part)
12 1st stage (active side member)
13 2nd stage (passive side member)
20 OIS fixed part (fixed part)
21 Base (active side member)
50X X-axis direction drive unit (drive unit)
50Y Y-axis direction drive unit (drive unit)
51 OIS resonance part (resonance part)
511, 512 Arm 60X X-axis direction power transmission section (power transmission section)
60Y Y-axis direction power transmission section (power transmission section)
61 Passive member 62 Connecting member A Camera module M Smartphone (camera mounted device)

Claims (7)

a fixed part;
a movable part including an optical element;
an ultrasonic motor-type drive unit that is disposed on an active side member consisting of either the fixed part or the movable part and moves the movable part with respect to the fixed part;
a power transmission section that connects the drive section and a passive side member consisting of the other of the fixed section and the movable section, and transmits the power of the drive section to the passive side member;
Equipped with
The driving section has a resonating section having a pair of vibrating arms,
The power transmission section is
a passive member held between the pair of arms in a biased state;
a connecting member that connects the passive member and the passive side member,
the connecting member is elastically deformable;
Optical element drive device. The connecting member is made of a metal material.
The optical element driving device according to claim 1. The connecting member is
a fixing part fixed to the passive member;
an elastic part extending from the fixed part and connected to the movable part,
the elastic part is arranged to extend in the moving direction of the movable part;
The optical element driving device according to claim 1 or 2. The active side member and the passive side member are supported by a ball so as to be relatively movable.
The optical element driving device according to claim 1 or 2. The passive member is less deformable than the pair of arms,
The width of the passive member in the direction sandwiched by the pair of arms is larger than the separation width of the pair of arms.
The optical element driving device according to claim 1 or 2. The optical element driving device according to claim 1;
an optical element attached to the movable part;
an imaging unit that captures a subject image formed by the optical element;
The camera module. A camera-equipped device that is an information device or a transportation device,
A camera module according to claim 6;
an image processing unit that processes image information obtained by the camera module;
Camera-equipped device.