Camera module and camera-equipped device

Abstract

Provided is a camera module and a camera-equipped device capable of accurately detecting the position of a movable member in a blade drive device and improving reliability. The camera module is provided with an optical element drive device and the blade drive device. The optical element drive device is provided with a first drive unit comprising a first coil and a plurality of first magnets. The blade drive device is provided with a second movable member and a blade detection sensor that magnetically detects the rotational operation of the second movable member. The blade detection sensor is disposed in a first region between adjacent first magnets in a plan view seen from the optical axis direction.

Description

Camera Module and Camera-Equipped Device

[0001] The present invention relates to a camera module and a camera-equipped device.

[0002] Generally, a small camera module (optical device) is mounted on a camera-equipped device such as a smartphone or a drone. A drone is an unmanned aircraft that can be flown by remote control or automatic control, and some are called multicopters.

[0003] An optical element driving device that drives an optical element such as a lens is used in the camera module. The optical element driving device has, for example, an autofocus function (hereinafter referred to as the "AF function", AF: Auto Focus) that moves an optical element (for example, a lens) in the optical axis direction and automatically focuses when shooting a subject, and a shake correction function (hereinafter referred to as the "OIS function", OIS: Optical Image Stabilization) that optically corrects shake (vibration) generated during shooting to reduce image blur.

[0004] In recent years, the development of a camera module equipped with a blade driving device capable of adjusting the amount of light incident on the optical element together with the optical element driving device has also been promoted (for example, see Patent Document 1). The blade driving device includes, for example, a fixed body, a movable body (rotating body) rotatable with respect to the fixed body, an aperture blade that moves to open and close the aperture in conjunction with the rotation of the movable body, and a driving unit that drives the movable body. The driving unit is composed of, for example, a motor having a coil disposed on the fixed body and a magnet disposed on the movable body.

[0005] In addition, the blade driving device and the optical element driving device often include a position detection unit that magnetically detects the position of the movable body in order to improve the operation accuracy of the movable body. For example, a hall element or the like is applied to the position detection unit.

[0006] Japanese Unexamined Patent Application Publication No. 2020-122915

[0007] When magnetically detecting the position of the movable body, it is important to minimize the influence of magnetism other than the magnetic element to be detected (for example, the magnet for position detection).

[0008] The object of the present invention is to provide a camera module and a camera-mounted device that can accurately detect the position of a movable body in a blade drive device and improve reliability.

[0009] The camera module according to the present invention comprises an optical element driving device capable of moving an optical element, and a vane driving device capable of adjusting the amount of light incident on the optical element through an aperture, wherein the optical element driving device comprises a first driving unit consisting of a first coil and a plurality of first magnets, a first fixed unit having one of the first coil and the first magnets, and a first movable unit having the other of the first coil and the first magnet and movable relative to the first fixed unit, wherein the vane driving device comprises a second driving unit consisting of a second coil and a second magnet, a second fixed unit having the second coil, a second movable unit having the second magnet and rotatable relative to the second fixed unit, and a vane detection sensor that magnetically detects the rotational movement of the second movable unit, wherein the vane detection sensor is arranged in a first region between adjacent first magnets in a plan view as seen from the optical axis direction.

[0010] The camera-mounted device according to the present invention is a camera-mounted device that is an information device or a transport device, and comprises the above-mentioned camera module.

[0011] According to the camera module and camera-mounted device of the present invention, the rotational position of the movable body in the blade drive device can be detected with high accuracy, thereby improving reliability.

[0012] Figures 1A and 1B show a smartphone equipped with a camera module according to one embodiment of the present invention. Figure 2 is an exploded perspective view of the camera module. Figure 3 is an exploded perspective view of the optical element driving device. Figure 4 is an exploded perspective view of the OIS movable part. Figure 5 is an exploded perspective view of the blade driving device. Figure 6 is an exploded perspective view of the blade driving motor. Figure 7 is an exploded perspective view of the blade driving motor. Figures 8A and 8B show the arrangement of the blade detection sensors. Figures 9A and 9B show an automobile as a camera-mounted device equipped with an in-vehicle camera module.

[0013] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[0014] <Smartphone> Figures 1A and 1B show a smartphone M (an example of a camera-equipped device) that is equipped with a camera module A according to one embodiment of the present invention. Figure 1A is a front view of the smartphone M, and Figure 1B is a rear view of the smartphone M.

[0015] Smartphone M has a dual camera consisting of two rear cameras OC1 and OC2. In this embodiment, camera module A is applied to the rear cameras OC1 and OC2.

[0016] <Camera Module> Figure 2 is an exploded perspective view of camera module A. In this embodiment, the Cartesian coordinate system (X, Y, Z) will be used for explanation. The same Cartesian coordinate system (X, Y, Z) will also be used in the figures described later.

[0017] Camera module A is mounted on a smartphone M such that, for example, the Z-axis direction is the optical axis direction, the upper side (+Z side) in the diagram is the light-receiving side along the optical axis, and the lower side (-Z side) is the image-forming side along the optical axis. The X-axis and Y-axis directions perpendicular to the Z-axis are referred to as the "orthogonal optical axis direction," and the XY plane is referred to as the "orthogonal optical axis plane." Note that the optical axis direction may also be referred to as the optical path direction or the focal direction (the direction in which the focus is adjusted), depending on the type of optical element.

[0018] Camera module A is equipped with an AF function, which allows for automatic focusing when photographing a subject. Furthermore, camera module A is equipped with an OIS function, which optically corrects camera shake (vibration) that occurs during shooting, enabling the capture of blur-free images.

[0019] As shown in Figure 2, the camera module A includes an optical element drive device 1, a lens unit 2, an imaging unit 3, and a blade drive device 4, etc.

[0020] The optical element driving device 1 of this embodiment is designed with consideration for mounting on the camera module A, etc., as described above, and has a configuration in which the length in the Z-axis direction is shorter than the lengths in the X-axis direction and the Y-axis direction, that is, a configuration in which the height along the Z-axis direction is reduced.

[0021] The optical element driving device 1 is configured, for example, to allow the lens unit 2 to move in the direction of the optical axis and in the direction perpendicular to the optical axis. The optical element driving device 1 realizes the AF function and / or zoom function by moving the lens unit 2 in the direction of the optical axis. Furthermore, the optical element driving device 1 realizes the OIS function by moving the lens unit 2 in the direction perpendicular to the optical axis. A detailed explanation of the optical element driving device 1 will be given later.

[0022] The lens unit 2 has a lens and a lens barrel that holds the lens. The lens unit 2 is housed and fixed in the optical element driving device 1. The lens unit 2 is an example of an optical element that is driven by the optical element driving device 1. The optical element that is driven by the optical element driving device 1 may be an optical element other than a lens, such as a mirror or a prism.

[0023] The imaging unit 3 captures the image of the subject formed by the lens unit 2. The imaging unit 3 is positioned on the imaging side in the Z-axis direction of the optical element driving device 1. The imaging unit 3 includes, for example, an image sensor substrate 3a, an image sensor 3b mounted on the image sensor substrate 3a, and a module control unit 3c.

[0024] The image sensor substrate 3a is, for example, a flexible printed circuit board (FPC) and is configured to transmit the imaging signal obtained by the image sensor 3b to the control device (not shown) of the smartphone M. The control device of the smartphone M includes an image processing unit (not shown) that processes the received imaging signal.

[0025] The image sensor 3b is composed of, for example, a CCD (charge-coupled device) type image sensor, a CMOS (complementary metal oxide semiconductor) type image sensor, and captures the image of the subject formed by the lens unit 2.

[0026] The module control unit 3c is composed of, for example, a control IC and controls the operation of the optical element drive device 1 and the blade drive device 4. The optical element drive device 1 is mounted on the image sensor substrate 3a and is mechanically and electrically connected. The module control unit 3c may be provided on the image sensor substrate 3a, or it may be provided on a camera-mounted device (in this embodiment, a smartphone M) on which the camera module A is mounted.

[0027] The blade drive device 4 adjusts the amount of light incident on the lens section 2. The blade drive device 4 is fixed to the movable part of the lens section 2 or the optical element drive device 1, and is movable in the optical axis direction together with the lens section 2 and the movable part of the optical element drive device 1. The blade drive device 4 is supplied with driving power and control signals (clock signal and data signal) via the optical element drive device 1. A detailed explanation of the blade drive device 4 will be given later.

[0028] <Optical Element Driving Device> Figure 3 is an exploded perspective view of the optical element driving device 1. Figure 4 is an exploded perspective view of the OIS movable part 10. As shown in Figures 3 and 4, the optical element driving device 1 includes the OIS movable part 10, the OIS fixed part 20, the OIS driving part 30, the OIS support part 40, the cover 24, etc. Note that the cover 24 is omitted in Figure 3.

[0029] The cover 24 is the exterior of the optical element driving device 1 and covers the outside of the driving device body (reference numeral omitted). The cover 24 is a covered rectangular cylinder that is roughly rectangular in shape when viewed from the Z-axis direction. The shape of the cover 24 in plan view is, for example, square. That is, the optical element driving device 1 has a rectangular shape that extends in the X-axis direction and the Y-axis direction when viewed from the Z-axis direction. In the following description, "plan view" means a plan view when viewed from the Z-axis direction.

[0030] The cover 24 has a substantially circular opening 241 on the light-receiving side (top surface) in the optical axis direction. The lens portion 2 faces outward from the opening 241 of the cover 24. The lens portion 2 may be positioned to protrude from the opening surface of the cover 24 towards the light-receiving side in the Z axis direction. The cover 24 is fixed to the base 21 of the optical element driving device 1 by adhesive, for example. The cover 24 may be formed of a magnetic material, for example, and may have a shielding function that blocks the incidence of electromagnetic waves from the outside or the radiation of electromagnetic waves to the outside.

[0031] The OIS movable part 10 is the part that oscillates in a plane perpendicular to the optical axis by receiving the driving force of the OIS drive unit 30 during shake correction. The OIS fixed part 20 is the part that supports the OIS movable part 10. The OIS fixed part 20 is, for example, positioned at a distance from the OIS movable part 10 toward the image formation side in the optical axis direction.

[0032] The OIS drive unit 30 consists of OIS coils 32A to 32D arranged in the OIS fixed unit 20 and optical element driving magnets 31A to 31D (OIS magnets) arranged in the OIS movable unit 10. In other words, a moving magnet type voice coil motor is applied to the OIS drive unit 30. Note that the OIS drive unit 30 may also be composed of a moving coil type voice coil motor.

[0033] The OIS support portion 40 is the part that connects the OIS movable portion 10 and the OIS fixed portion 20. The OIS support portion 40 supports the OIS movable portion 10 so that it can swing within a plane perpendicular to the optical axis relative to the OIS fixed portion 20.

[0034] In the optical element drive device 1, a guaranteed stroke is defined that indicates the degree to which proper vibration correction can be performed. That is, the shape, size, and strength of the components of the OIS movable part 10, OIS fixed part 20, OIS drive part 30, and OIS support part 40 are set so as to achieve the guaranteed stroke.

[0035] The OIS movable part 10 is composed of an AF unit including, for example, a lens holder 11, a magnet holder 12, an AF coil 13, magnets 31A to 31D for driving optical elements, an upper elastic support part 15, a lower elastic support part 16, and an AF drive circuit board part 50.

[0036] The lens holder 11 is a movable body that holds the lens portion 2 (see Figure 2) and moves in the Z-axis direction when focusing. The lens holder 11 is an example of the "first movable part" in the present invention. The lens holder 11 is positioned radially inward and spaced apart from the magnet holder 12, and is connected to the magnet holder 12 by an upper elastic support portion 15 and a lower elastic support portion 16.

[0037] The lens holder 11 is formed from, for example, polyarylate (PAR), a PAR alloy obtained by mixing multiple resin materials including PAR, or a liquid crystal polymer.

[0038] The lens holder 11 has a cylindrical lens housing portion 111. The lens portion 2 (see Figure 3) is fixed to the inner circumferential surface of the lens housing portion 111, for example, by adhesive. An AF coil 13 is attached to the outer circumferential surface of the lens holder 11.

[0039] An upper elastic support portion 15 is fixed to the upper surface of the lens holder 11 (the upper end surface of the lens housing portion 111). The upper elastic support portion 15 is positioned, for example, by a positioning boss (not shown in the reference numerals) provided on the upper surface of the lens holder 11.

[0040] On the lower surface of the lens holder 11, a lower elastic support portion 16 is fixed. The lower elastic support portion 16 is positioned, for example, by a positioning boss (not shown) provided on the lower surface of the lens holder 11. Further, the lens holder 11 has a winding portion (not shown) on its lower surface to which an end portion of the AF coil 13 is connected.

[0041] The magnet holder 12 is a fixing body that supports the lens holder 11 so as to be movable in the Z-axis direction via the upper elastic support portion 15 and the lower elastic support portion 16. The magnet holder 12 is an example of the "first fixing portion" in the present invention. The magnet holder 12 has, for example, a substantially rectangular square tube shape in a plan view seen from the Z-axis direction. The lens holder 11 is disposed in the opening 121 of the magnet holder 12.

[0042] The magnet holder 12 is formed of, for example, a molding material made of polyarylate (PAR), a PAR alloy (for example, PAR / PC) obtained by mixing a plurality of resin materials including PAR, or a liquid crystal polymer.

[0043] The magnet holder 12 has a magnet housing portion 123 inside the connecting portions (the four corners of the magnet holder 12) of the four side wall bodies 122, in which the magnets 31A to 31D for driving the optical element are fixed. The magnet housing portion 123 is provided with, for example, an opening (not shown) communicating with the outside, and an adhesive can be injected onto the contact surface between the magnet housing portion 123 and the magnets 31A to 31D for driving the optical element.

[0044] The magnet holder 12 has a wire insertion portion 124 that is recessed in an arc shape radially inward on the outside of the connecting portion of the side wall body 122. The suspension wires 41 to 48 are disposed in the wire insertion portion 124. By providing the wire insertion portion 124, it is possible to avoid interference between the suspension wires 41 to 48 and the magnet holder 12 when the OIS movable portion 10 swings.

[0045] The magnet holder 12 has a board fixing portion 125 for fixing the AF drive circuit board portion 50 on the outer peripheral surface of one side wall body 122. Although not shown, the board fixing portion 125 is formed with a recess capable of accommodating the driver IC 52 (drive control portion) and the capacitor 53 of the AF drive circuit board portion 50.

[0046] On the upper surface of the side wall body 122, the upper elastic support portion 15 is fixed. On the lower surface of the side wall body 122, the lower elastic support portion 16 is fixed. The periphery of the wire insertion portion 124 is formed to be inclined downward from the mounting surface of the upper elastic support portion 15 so that a gap is formed when the upper elastic support portion 15 is mounted.

[0047] The AF coil 13 is an air-core coil that is energized during autofocus. The AF coil 13 is wound around the coil winding portion (the outer peripheral surface of the lens housing portion 111) of the lens holder 11. The AF coil 13 constitutes a voice coil motor together with the optical element driving magnets 31A to 31D and functions as an AF driving portion. The AF driving portion is an example of the "first driving portion" in the present invention.

[0048] Both ends of the AF coil 13 are respectively wound around the winding portions of the lens holder 11. The AF coil 13 is energized through, for example, the lower elastic support portion 16. The energization current of the AF coil 13 is controlled by, for example, the driver IC 52 mounted on the AF drive circuit board portion 50.

[0049] The optical element driving magnets 31A to 31D are fixed to the magnet holder 12 by, for example, adhesion. In the present embodiment, the optical element driving magnets 31A to 31D have a substantially isosceles trapezoidal shape in a plan view. Thereby, the space at the corners of the magnet holder 12 can be effectively utilized.

[0050] The magnets 31A to 31D for driving the optical elements are arranged so as to be spaced radially apart from the AF coil 13 and spaced in the optical axis direction from the OIS coils 32A to 32D. The magnets 31A to 31D for driving the optical elements are magnetized such that a magnetic field is formed that crosses the AF coil 13 radially and the OIS coils 32A to 32D in the optical axis direction.

[0051] The magnets 31A to 31D for driving the optical elements, together with the AF coil 13, constitute a voice coil motor and function as an AF drive unit. Furthermore, the magnets 31A to 31D for driving the optical elements, together with the OIS coils 32A to 32D, constitute a voice coil motor and function as an OIS drive unit 30. In other words, in this embodiment, the magnets 31A to 31D for driving the optical elements serve as both AF magnets and OIS magnets.

[0052] The upper elastic support portion 15 elastically supports the lens holder 11 relative to the magnet holder 12 on the light-receiving side in the optical axis direction. The upper elastic support portion 15 is made of, for example, titanium copper, nickel copper, stainless steel, etc. The upper elastic support portion 15 as a whole has a rectangular shape in plan view, that is, the same shape as the magnet holder 12.

[0053] The upper elastic support section 15 is composed of a plurality of upper spring elements (for example, six). The plurality of upper spring elements are arranged so as not to contact each other and function as a leaf spring. The upper spring elements are formed, for example, by etching a single sheet of metal. Together with the suspension wires 41 to 48, the upper spring elements function as a common signal line, an AF power line, an AF signal line, a common power line, a blade drive power line, and a blade drive signal line.

[0054] The lower elastic support portion 16 elastically supports the lens holder 11 relative to the magnet holder 12 on the optical axis imaging side. The lower elastic support portion 16 is made of, for example, titanium copper, nickel copper, stainless steel, etc. The lower elastic support portion 16 as a whole has a rectangular shape in plan view, that is, the same shape as the magnet holder 12.

[0055] The lower elastic support portion 16 is composed of a plurality of lower spring elements (for example, two). The plurality of lower spring elements are arranged so as not to contact each other and function as a leaf spring. The lower spring elements are formed, for example, by etching a single sheet of metal. The lower spring elements function as a coil power supply line that supplies power from the AF drive circuit board portion 50 to the AF coil 13.

[0056] The AF drive circuit board section 50 includes a flexible printed circuit board 51 (hereinafter referred to as "FPC 51", FPC: Flexible Printed Circuit), a driver IC 52, a capacitor 53, etc. The AF drive circuit board section 50 is placed on the board fixing section 125 of the magnet holder 12.

[0057] The FPC 51 is a circuit board on which the driver IC 52 and capacitor 53 are mounted. The FPC 51 is formed by laminating a thin insulating layer, such as a resin film, with a metal layer, such as copper foil. Circuit wiring, such as signal lines and power lines, is formed by the metal layer. The upper spring element, lower spring element, and driver IC 52 are electrically connected to the circuit wiring of the FPC 51.

[0058] The driver IC 52 is a hardware processor that controls the current supplied to the AF coil 13. The driver IC 52 has a built-in AF detection sensor 54 (see Figure 8A).

[0059] The AF detection sensor 54 is an example of an "optical element detection sensor" in the present invention. The AF detection sensor 54 primarily detects the magnetic flux of the AF detection magnet 55 (see Figure 7A). The AF detection sensor 54 is positioned in the magnet holder 12 (first fixed part) and magnetically detects the movement of the lens holder 11 (first movable part), specifically the relative position between the lens holder 11 and the magnet holder 12 in the optical axis direction. The AF detection sensor 54 is, for example, a magnetic sensor such as a Hall element or a TMR (Tunnel Magneto Resistance) sensor.

[0060] The AF detection magnet 55 is an example of an "optical element detection magnet" in the present invention. The AF detection magnet 55 is positioned in the lens holder 11 so as to face the AF detection sensor 54 in the radial direction.

[0061] Furthermore, a dummy magnet 56, having the same structure as the AF detection magnet 55, is positioned at a location 180° around the optical axis O. The dummy magnet 56 is positioned to balance the weight and magnetic balance and stabilize the orientation of the lens holder 11.

[0062] The driver IC 52 controls the energizing current of the AF coil 13 based, for example, on the control signal from the module control unit 3c and the detection result of the AF detection sensor 54.

[0063] The OIS fixing section 20 is composed of, for example, a base 21 and OIS coils 32A to 32D.

[0064] The base 21 has a rectangular shape in plan view, with a circular opening 211 formed in the center. In the camera module A, an image sensor substrate 3a on which an image sensor 3b is mounted is positioned on the optical axis imaging side of the base 21.

[0065] For example, wiring connectors (not shown) are embedded in the base 21 by insert molding. The wiring connectors are electrically connected to the wiring pattern of the image sensor substrate 3a and form power lines for supplying power to the OIS coils 32A to 32D, as well as signal lines for detection signals output from the magnetic sensor.

[0066] Furthermore, the wiring connectors form power lines for supplying power to the AF drive circuit board section 50 and the blade drive device 4 of the OIS movable section 10, as well as signal lines for supplying control signals. The wiring connectors are exposed from the four corners of the base 21 and are connected to the suspension wires 41 to 48 by soldering.

[0067] The OIS coils 32A to 32D are positioned opposite the optical element driving magnets 31A to 31D in the optical axis direction. The OIS coils 32A to 32D are air-core coils that are energized during vibration correction. The size and arrangement of the OIS coils 32A to 32D and the optical element driving magnets 31A to 31D are set so that the radial edges of the optical element driving magnets 31A to 31D fit within the cross-sectional width of each coil of the OIS coils 32A to 32D, that is, so that the magnetic field radiated from the bottom surface of the optical element driving magnets 31A to 31D crosses two opposing sides of the OIS coils 32A to 32D and returns to the optical element driving magnets 31A to 31D.

[0068] Here, the OIS coils 32A to 32D have a shape similar to the planar shape (in this case, roughly isosceles trapezoidal) of the optical element driving magnets 31A to 31D. This allows for efficient generation of the driving force (electromagnetic force) necessary to oscillate the OIS movable part 10 in the plane orthogonal to the optical axis. The current supplied to the OIS coils 32A to 32D is controlled, for example, by the module control unit 3c.

[0069] Although not shown in the diagram, an OIS detection sensor may be mounted on the base 21. The OIS detection sensor is located on the OIS fixed part 20 and magnetically detects the operation of the OIS movable part 10. The OIS detection sensor is a magnetic sensor such as a Hall element or a TMR (Tunnel Magneto Resistance) sensor. The OIS detection sensor is located, for example, at two locations facing the optical element driving magnets 31B and 31C in the optical axis direction and mainly detects the magnetic flux of the optical element driving magnets 31B and 31C. The OIS detection sensor is located, for example, in the air core portion of the OIS coils 32B and 32C.

[0070] The OIS support section 40 is composed of multiple wire members. In this embodiment, the OIS support section 40 is composed of eight suspension wires 41 to 48. The suspension wires 41 to 48 are arranged in pairs at the four corners of a rectangular shape in plan view. The suspension wires 41 to 48 are linear members extending in the direction of the optical axis and elastically deform as the OIS movable section 10 swings. One end of each suspension wire 41 to 48 (the end on the light-receiving side in the optical axis direction, the upper end) is fixed to the OIS movable section 10, and the other end (the end on the image-forming side in the optical axis direction) is fixed to the OIS fixed section 20. The suspension wires 41 to 48 are electrically and mechanically connected, for example, to the upper elastic support section 15 of the OIS movable section 10 and the wiring fittings (not shown) of the OIS fixed section 20.

[0071] The suspension wire 41 functions, for example, as a common signal line, an AF power supply line, an AF signal line, a common power supply line, a blade drive power supply line, and a blade drive signal line. The common signal line supplies a clock signal to the AF drive circuit board 50 and the blade drive device 4. The AF power supply line supplies positive power to the AF drive circuit board 50. The AF signal line supplies data signals to the AF drive circuit board 50. The common power supply line supplies negative power (ground) to the AF drive circuit board 50 and the blade drive device 4. The blade drive power supply line supplies positive power to the blade drive device 4. The blade drive signal line supplies data signals to the blade drive device 4.

[0072] When vibration correction is performed in the optical element driving device 1, power is supplied to the OIS coils 32A to 32D. Specifically, in the OIS driving unit 30, the current supplied to the OIS coils 32A to 32D is controlled based on the detection signal from the vibration detection unit (not shown, for example, a gyro sensor) so that the vibration of the camera module A is canceled out. At this time, the oscillation of the OIS movable part 10 can be accurately controlled by feeding back the detection result of the magnetic sensor (not shown).

[0073] When current is applied to the OIS coils 32A to 32D, a Lorentz force is generated in the OIS coils 32A to 32D due to the interaction between the magnetic field of the optical element driving magnets 31A to 31D and the current flowing through the OIS coils 32A to 32D (Fleming's left-hand rule). The direction of the Lorentz force is perpendicular to the direction of the magnetic field (Z-axis direction) and the direction of the current in the long side portion of the OIS coils 32A to 32D. Since the OIS coils 32A to 32D are fixed, a reaction force acts on the optical element driving magnets 31A to 31D. This reaction force becomes the driving force of the OIS voice coil motor, causing the OIS movable part 10 having the optical element driving magnets 31A to 31D to oscillate in the XY plane, and vibration correction is performed.

[0074] When autofocus is performed in the optical element driving device 1, power is supplied to the AF coil 13. Power is supplied to the AF coil 13 from the AF drive circuit board 50 via a lower spring element. When power is supplied to the AF coil 13, a Lorentz force is generated in the AF coil 13 due to the interaction between the magnetic field of the optical element driving magnets 31A to 31D and the current flowing through the AF coil 13. The direction of the Lorentz force is perpendicular to the direction of the magnetic field from the optical element driving magnets 31A to 31D and the direction of the current flowing through the AF coil 13 (Z-axis direction). Since the optical element driving magnets 31A to 31D are fixed, a reaction force acts on the AF coil 13. This reaction force becomes the driving force of the AF voice coil motor, causing the lens holder 11 (AF movable part) on which the AF coil 13 is located to move in the optical axis direction, and autofocus is performed.

[0075] In the driver IC 52 of the optical element drive device 1, closed-loop control is performed based on the detection signal from the built-in AF detection sensor 54. The closed-loop control method eliminates the need to consider the hysteresis characteristics of the voice coil motor and allows for direct detection of the lens holder 11's stable position. Furthermore, it supports image plane detection type autofocus. Therefore, it offers high response performance and enables faster autofocus operation.

[0076] <Blade Drive System> Figure 5 is an exploded perspective view of the blade drive system 4. Figures 6 and 7 are exploded perspective views of the blade drive motor 60.

[0077] As shown in Figure 5, the blade drive device 4 includes a blade drive motor 60, an opening member 71, aperture blades 72, and a cover 73, etc. As shown in Figures 6 and 7, the blade drive motor 60 has a rotor 61 (second movable part) and a stator 62 (second fixed part).

[0078] The aperture member 71 defines the opening of the blade drive device 4 when the aperture blades 72 are in the fully open position. The aperture member 71 has an opening 71a in the center. In plan view, the outer shape of the aperture member 71 is the same as the outer shape of the bulge 622e of the stator base 622. The aperture member 71 has a plurality of fixing holes 71b. In this embodiment, there are six fixing holes 71b. The fixing holes 71b are fitted onto the engagement pins 622d of the stator base 622. The aperture member 71 is attached to the stator base 622 of the stator 62.

[0079] The aperture blades 72 are mounted so as to straddle the stator 62 and rotor 61 of the blade drive motor 60 via the aperture material 71. The aperture blades 72 move in conjunction with the rotation of the rotor 61 to open and close the opening of the blade drive device 4.

[0080] The aperture blades 72 are composed of a plurality of blade members 721. The plurality of blade members 721 are arranged alternately in the circumferential direction. Each of the plurality of blade members 721 has a fixing hole 721b and a cam hole 721c. The fixing hole 721b is fitted onto the engagement pin 612b of the rotor frame 612. The cam hole 721c engages with the engagement pin 622d of the stator base 622.

[0081] The cover 73 is positioned on the light-receiving side of the aperture blades 72 in the optical axis direction to prevent the aperture blades 72 from falling off. The cover 73 has an opening 73a in the center. In plan view, the outer shape of the cover 73 is the same as the outer shape of the bottom surface 622a of the stator base 622. The cover 73 is fixed to the stator base 622, for example, by adhesive.

[0082] The cover 73 has a plurality of guide holes 73b and fixing holes 73c. ​​In this embodiment, there are six guide holes 73b and six fixing holes 73c. ​​The guide holes 73b are formed in an arc shape so as to extend along the circumferential direction. The guide holes 73b engage with the engagement pins 612b of the rotor frame 612. The fixing holes 73c are fitted onto the engagement pins 622d of the stator base 622.

[0083] In the blade drive motor 60, the rotor 61 is rotatable relative to the stator 62 via a support portion (not shown). The blade drive motor 60 is a so-called axial gap type rotary motor in which the stator 62 and rotor 61 face each other in the direction of the rotation axis. The direction of rotation axis of the blade drive motor 60 coincides with the optical axis direction of the blade drive device 4.

[0084] The rotor 61 is a movable body that is rotatably supported by the stator 62. The stator 62 is a fixed body that supports the rotor 61 so that it can rotate in the circumferential direction around the optical axis (rotation axis). For example, the rotor 61 is rotatably supported by the stator 62 by the engagement of a recess formed in the stator base 622 with a protrusion formed in the rotor frame 612. The blade drive coil 621 and the blade drive magnet 611 constitute a blade drive unit (second drive unit) that rotates the rotor 61 relative to the stator 62.

[0085] The rotor 61 includes a blade drive magnet 611 and a rotor frame 612. The rotor 61 is formed by assembling the blade drive magnet 611 to the rotor frame 612.

[0086] The blade drive magnet 611 is a ring-shaped magnet in which the south pole and north pole are arranged alternately in the circumferential direction. The shape of the blade drive magnet 611 is the same as the main body portion 623a of the coil substrate 623. In the blade drive motor 60, the blade drive magnet 611 and the blade drive coil 621 are arranged to face each other in the optical axis direction (rotation axis direction). The blade drive magnet 611 is fixed to the magnet arrangement portion 612c of the rotor frame 612.

[0087] The rotor frame 612 is a holder that holds the blade drive magnet 611. The rotor frame 612 has a frame body portion 612a and an engagement pin 612b. The frame body portion 612a has a ring shape, similar to the blade drive magnet 611. The engagement pin 612b is formed to protrude toward the light-receiving side in the optical axis direction. The engagement pin 612b is provided corresponding to the guide hole 73b of the cover 73.

[0088] The stator 62 includes a blade drive coil 621, a stator base 622, a coil substrate 623, and a yoke (not shown). The stator 62 is constructed by assembling the blade drive coil 621, the coil substrate 623, and the yoke onto the stator base 622.

[0089] The blade drive coil 621 is, for example, a planar coil in which a conductor is wound in a spiral shape. The blade drive coil 621 has a rectangular or oval shape. Multiple blade drive coils 621 are arranged on the coil substrate 623 along the circumferential direction. The blade drive coils 621 are arranged, for example, on the back surface of the coil substrate 623 (the surface on the optical axis direction imaging side). The blade drive coils 621 may also be fabricated inside the coil substrate 623.

[0090] The stator base 622 constitutes the housing of the blade drive motor 60. The stator base 622 is a low-profile, bottomed cylindrical member having a bottom surface portion 622a and a circumferential surface portion 622b. The stator base 622 has an opening 622c in the center of the bottom surface portion 622a. The stator base 622 has an engagement pin 622d on the periphery of the opening 622c. The engagement pin 622d is formed to protrude from a bulge portion 622e formed on the periphery of the opening 622c toward the light-receiving side in the optical axis direction. The engagement pin 622d is provided corresponding to the fixing hole 71b of the opening material 71 and the fixing hole 73c of the cover 73. The stator base 622 also has notches 622f at two radially opposite locations on the circumferential surface portion 622b.

[0091] The coil substrate 623 has a substrate body portion 623a and a terminal portion 623b. The shape of the substrate body portion 623a conforms to the shape of the bottom surface portion 622a of the stator base 622. The substrate body portion 623a has, for example, a ring shape. The terminal portion 623b is connected, for example, to two radially opposing locations on the substrate body portion 623a. The coil substrate 623 is placed on and fixed to the bottom surface portion 622a of the stator base 622. The terminal portion 623b is pulled out radially outward from the notch portion 622f of the stator base 622.

[0092] The coil substrate 623 is a flexible printed circuit board on which the blade drive coil 621 is mounted. The coil substrate 623 is formed by laminating a thin insulating layer, such as a resin film, and a metal layer, such as copper foil. Circuit wiring (not shown) such as signal lines and power lines is formed in the metal layer. A portion of the metal layer located at the terminal portion 623b is exposed and is electrically and mechanically connected to the electrical system of the optical element drive device 1.

[0093] Furthermore, a blade detection sensor 624 is mounted on the coil substrate 623 to magnetically detect the rotational movement of the rotor 61 (blade drive magnet 611). The blade detection sensor 624 is positioned, for example, between adjacent blade drive coils 621 on the back surface of the coil substrate 623 (the surface on the optical axis direction imaging side). The detection surface of the blade detection sensor 624 faces the blade drive magnet 611 in the optical axis direction. In other words, the blade detection sensor 624 mainly detects the magnetic flux of the blade drive magnet 611. The blade detection sensor 624 is a magnetic sensor such as a Hall element or a TMR (Tunnel Magneto Resistance) sensor.

[0094] The yoke (not shown) is made of a magnetic material. The yoke is, for example, fitted and fixed to the bottom surface 622a of the stator base 622. The yoke is positioned to face the blade drive magnet 611 in the optical axis direction (rotation axis direction), generating a magnetic attractive force on the blade drive magnet 611. It is also possible to adjust the magnetic attractive force by fixing the yoke to the back surface of the stator base 622 (the surface on the optical axis direction imaging side). The coil substrate 623 (blade drive coil 621) is sandwiched between the yoke and the blade drive magnet 611. By positioning the yoke, the magnetic flux radiated from the blade drive magnet 611 can be efficiently intersected with the blade drive coil 621.

[0095] The size and arrangement of the blade drive magnet 611 and the blade drive coil 621 are set so that the magnetic flux of the blade drive magnet 611 crosses two circumferentially opposing sides (circumferentially opposing portions) of the blade drive coil 621 and returns to the blade drive magnet 611. Note that the configuration of the blade drive magnet 611 and the blade drive coil 621 is not limited to that described in the embodiment and can be changed as appropriate.

[0096] The blade drive unit 4 is assembled by sequentially placing the rotor 61, aperture material 71, and aperture blades 72 on the stator 62, and then fixing the cover 73 to the stator base 622 of the stator 62.

[0097] The blade drive unit 4 is supplied with power and control signals (clock signals and data signals) via the electrical system of the optical element drive unit 1. Based on the supplied power and control signals, the blade drive motor 60 is driven, causing the rotor 61 to rotate relative to the stator 62.

[0098] Specifically, when current is applied to the blade drive coil 621, a Lorentz force is generated in the blade drive coil 621 due to the interaction between the magnetic field of the blade drive magnet 611 and the current flowing through the blade drive coil 621 (Fleming's left-hand rule). The direction of the Lorentz force is perpendicular to the direction of the magnetic field (Z-axis direction) and the direction of the current at the circumferentially opposing portion of the blade drive coil 621.

[0099] In the two circumferentially opposing sections, the direction of the current flowing is opposite, and the direction of the intersecting magnetic fluxes is also opposite, so a Lorentz force is generated in the same direction in the circumferential direction. In the two radially opposing sections, the direction of the current flowing is opposite, and the direction of the intersecting magnetic fluxes is the same, so a Lorentz force is generated in opposite directions in the radial direction, and they cancel each other out. The energization of each blade drive coil 621 is controlled so that a Lorentz force is generated in the same direction in the circumferential direction in all of the blade drive coils 621. Since the blade drive coils 621 are fixed, a reaction force acts on the blade drive magnet 611. This reaction force becomes the driving force of the blade drive motor 60, and the rotor 61 having the blade drive magnet 611 rotates.

[0100] As the rotor 61 rotates, the engagement pin 612b of the rotor frame 612 moves circumferentially. Since the movement of the aperture blades 72 is restricted by the cam hole 721c and the engagement pin 622d of the stator base 622, the aperture blades 72 rotate around the engagement pin 612b of the rotor frame 612. This opens and closes the opening of the blade drive device 4, adjusting the amount of light incident on the lens section 2. At this time, the operating accuracy of the rotor 61 can be improved by performing closed-loop control based on the detection signal of the blade detection sensor 624.

[0101] <Arrangement of detection sensors for blades> Figures 8A and 8B show the arrangement of the detection sensors 624 for blades. Figure 8A is a plan view seen from the tip side in the Z-axis direction. Figure 8B is a side view seen from the base end side in the Y-axis direction. Figures 8A and 8B show the arrangement of the main magnetic elements, and components other than the magnetic elements are omitted.

[0102] As described above, the optical element drive unit 1 and the blade drive unit 4 are equipped with numerous magnetic elements. The blade detection sensor 624 primarily detects the magnetic flux of the blade drive magnet 611, which is the target of detection, but it may be affected by other magnetic elements. In this embodiment, the arrangement of the blade detection sensor 624 is improved to suppress the magnetic influence of other magnetic elements that are not the target of detection.

[0103] In particular, among the other magnetic elements, the magnets 31A to 31D for driving the optical elements have the greatest magnetic influence on the blade detection sensor 624. Therefore, in this embodiment, the blade detection sensor 624 is positioned on the stator 62 at a location where the magnetic influence from the magnets 31A to 31D for driving the optical elements is minimized. As a result, the magnetic influence from the magnets 31C and 31D for driving the optical elements on the blade detection sensor 624 is suppressed, improving the detection accuracy of the blade detection sensor 624 and enabling proper control of the rotor 61's operation.

[0104] Specifically, as shown in Figure 8A, the vane detection sensor 624 is positioned in a first region R1 between adjacent optical element driving magnets 31C and 31D. The first region R1 can be defined as the region between effective magnetic regions MR3 and MR4 when the effective magnetic regions MR1 ​​to MR4 of the optical element driving magnets 31A to 31D are defined as a set of straight lines connecting each optical element driving magnet 31A to 31D to the optical axis O.

[0105] More specifically, the blade detection sensor 624 is positioned within the first region R1 at a location where the magnetic influence from both the optical element driving magnets 31C and 31D is the same, that is, at a position equidistant from both the optical element driving magnets 31C and 31D.

[0106] It is preferable that the AF detection sensor 54, which is built into the driver IC 62 of the optical element drive device 1, be arranged in the same way as the blade detection sensor 624. That is, the AF detection sensor 54 is located in a second region R2 between adjacent optical element drive magnets 31A and 31D. The second region R2 is the region between the effective magnetic regions MR1 ​​and MR4. This suppresses the magnetic influence of the optical element drive magnets 31A and 31D on the AF detection sensor 54, thereby improving the detection accuracy of the AF detection sensor 54 and enabling proper control of the operation of the lens holder 11.

[0107] Furthermore, the first region R1 where the blade detection sensor 624 is located and the second region R2 where the AF detection sensor 54 is located are different regions. This suppresses the magnetic influence of the AF detection magnet 55 on the blade detection sensor 624. In particular, it is preferable that the first region R1 and the second region R2 are 90° rotationally symmetric about the optical axis O. In this case, the magnetic influence of the dummy magnet 56 on the blade detection sensor 624 can also be suppressed.

[0108] Thus, this embodiment discloses a camera module A that includes the following features individually or in appropriate combinations.

[0109] In other words, camera module A includes an optical element drive device 1 that can move the lens section 2 (optical element), and a vane drive device 4 that can adjust the amount of light incident on the lens section 2 through the aperture. The optical element drive device 1 includes an AF drive unit (first drive unit) consisting of an AF coil 13 (first coil) and a plurality of optical element drive magnets 31A to 31D (first magnets), a magnet holder 12 (first fixed unit) having optical element drive magnets 31A to 31D (one of the first coil and the first magnet), and a lens holder 11 (first movable unit) having the AF coil 13 (the other of the first coil and the first magnet) and movable relative to the magnet holder 12. The blade drive device 4 comprises a blade drive unit (second drive unit) consisting of a blade drive coil 621 (second coil) and a blade drive magnet 611 (second magnet), a stator 62 (second fixed unit) having the blade drive coil 621, a rotor 61 (second movable unit) having the blade drive magnet 611 and rotatable relative to the stator 62, and a blade detection sensor 624 that magnetically detects the rotational movement of the rotor 61. The blade detection sensor 624 is positioned in a first region R1 between optical element drive magnets 31C and 31D (adjacent first magnets) in a plan view from the optical axis direction.

[0110] In camera module A, the blade detection sensor 624 is positioned outside the effective magnetic regions MR1 ​​to MR4 of the optical element driving magnets 31A to 31D (first magnets), which are a collection of straight lines connecting the optical element driving magnets 31A to 31D (first magnets) and the optical axis O.

[0111] In camera module A, the optical element driving device 1 further includes an AF detection sensor 54 (optical element detection sensor) positioned on the lens holder 11 (one of the first movable part and the first fixed part) to magnetically detect the movement of the lens holder 11, and an AF detection magnet 55 (optical element detection magnet) positioned opposite the AF detection sensor 54 on the magnet holder 12 (the other of the first movable part and the first fixed part). The AF detection sensor 54 and the AF detection magnet 55 are positioned in a second region R2, which is different from the first region R1, in a plan view from the optical axis direction, in the region between adjacent optical element driving magnets 31A and 31D.

[0112] In camera module A, the blade drive coil 621 (second coil) and the blade drive magnet 611 (second magnet) are arranged opposite each other in the optical axis direction, and the blade detection sensor 624 is arranged opposite the blade drive magnet 611 in the optical axis direction and mainly detects the magnetic flux of the blade drive magnet 611.

[0113] According to camera module A, the magnetic influence from the optical element drive magnets 31C and 31D on the blade detection sensor 624 is suppressed, so the rotational position of the rotor 61 in the blade drive device 4 can be detected with high accuracy, and reliability is greatly improved.

[0114] Although the present invention has been specifically described above based on embodiments, the present invention is not limited to the above embodiments and can be modified without departing from its spirit.

[0115] For example, although the above embodiment was described using a smartphone M as an example, the present invention can be applied to a camera-mounted device having a camera module and an image processing unit that processes image information obtained by the camera module. The camera-mounted device includes information equipment and transportation equipment. Information equipment includes, for example, mobile phones with cameras, notebook computers, tablet terminals, portable game consoles, webcams, and in-vehicle devices with cameras (e.g., rearview monitors, drive recorders). Transportation equipment includes, for example, automobiles and drones (unmanned aerial vehicles).

[0116] Figures 9A and 9B show a vehicle V as a camera-mounted device equipped with an in-vehicle camera module VC (Vehicle Camera). Figure 9A is a front view of the vehicle V, and Figure 9B is a rear perspective view of the vehicle V. The vehicle V is equipped with the camera module A described in the above embodiment as the in-vehicle camera module VC. As shown in Figures 9A and 9B, the in-vehicle camera module VC can be mounted, for example, on the windshield facing forward or on the rear gate facing backward. This in-vehicle camera module VC is used for purposes such as a backup monitor, a drive recorder, collision avoidance control, and autonomous driving control.

[0117] The embodiments disclosed herein should be considered in all respects to be illustrative and not restrictive. The scope of the present invention is indicated by the claims rather than by the foregoing description, and all modifications within the meaning and scope equivalent to the claims are intended to be included.

[0118] All disclosures in the specification, drawings, and abstract contained in the Japanese application No. 2024-225178, filed on December 20, 2024, are incorporated herein by reference.

[0119] 1 Optical element driving device, 2 Lens section (optical element), 3 Imaging section, 4 Blade driving device, 10 OIS movable section, 11 Lens holder (first movable section), 12 Magnet holder (first fixed section), 13 AF coil (first coil), 15 Upper elastic support section, 16 Lower elastic support section, 20 OIS fixed section, 21 Base, 30 OIS driving section, 31A-31D Magnet for optical element driving (first magnet), 32A-32D OIS coil, 40 OIS support section, 50 AF driving circuit board section, 54 AF detection sensor (detection sensor for optical element), 55 AF detection magnet (detection magnet for optical element), 56 Dummy magnet, 60 Blade driving motor, 61 Rotor (second movable section), 611 Blade driving magnet (second magnet), 612 Rotor frame, 62 Stator (second fixing part), 621 Blade drive coil (second coil), 622 Stator base, 624 Blade detection sensor, A Camera module, M Smartphone (camera mounted device), R1 First region, R2 Second region, MR1-MR4 Effective magnetic region

Claims

1. A camera module comprising an optical element drive device capable of moving an optical element, and a vane drive device capable of adjusting the amount of light incident on the optical element through an aperture, wherein the optical element drive device comprises a first drive unit consisting of a first coil and a plurality of first magnets, a first fixed unit having one of the first coil and the first magnets, and a first movable unit having the other of the first coil and the first magnet and movable relative to the first fixed unit, and the vane drive device comprises a second drive unit consisting of a second coil and a second magnet, a second fixed unit having the second coil, a second movable unit having the second magnet and rotatable relative to the second fixed unit, and a vane detection sensor that magnetically detects the rotational movement of the second movable unit, wherein the vane detection sensor is located in a first region between adjacent first magnets in a plan view as seen from the optical axis direction.

2. The camera module according to claim 1, wherein the vane detection sensor is located outside the magnetic region of the first magnet, which is a set of straight lines connecting the first magnet and the optical axis.

3. The camera module according to claim 1, wherein the optical element driving device further comprises: an optical element detection sensor disposed on one of the first movable part and the first fixed part for magnetically detecting the operation of the first movable part; and an optical element detection magnet disposed on the other of the first movable part and the first fixed part, facing the optical element detection sensor, wherein the optical element detection sensor and the optical element detection magnet are disposed in a second region different from the first region, in a plan view from the optical axis direction, in the region between adjacent first magnets.

4. The camera module according to claim 1, wherein the second coil and the second magnet are arranged opposite to each other in the direction of the optical axis, and the vane detection sensor is arranged opposite to the second magnet in the direction of the optical axis and mainly detects the magnetic flux of the second magnet.

5. A camera-mounted device which is an information device or a transport device, comprising the camera module described in claim 1.

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