JP4765457B2 - Lens driving device and camera-equipped mobile phone - Google Patents

Description

  The present invention relates to a lens driving device, and more particularly to a lens driving device capable of moving a lens in the optical axis direction of the lens and a camera-equipped mobile phone using the lens driving device.

  For example, a camera-equipped mobile phone is known as a camera-equipped mobile device using a lens driving device. In general, in such a camera-equipped mobile phone, the camera function is often used with an unstable posture such as taking a subject with a mobile phone with one hand.

  Therefore, as a countermeasure when the camera function is used in an unstable posture, the movable lens barrel containing the lens used in the lens driving device is sandwiched between two elastic members and moved in the optical axis direction. A technique for stabilizing the movement of the lens barrel is known (see Patent Document 1).

JP 2004-333955 A

  In recent years, mobile phones with cameras have been required to be small and thin for convenience of carrying, and naturally, the lens drive devices used for mobile phones with cameras are also downsized and thin. Is required.

  However, since the lens driving device disclosed in Patent Document 1 employs a configuration in which the movable barrel is sandwiched between two elastic members, a space for arranging the two elastic members is provided in the lens driving device. As a result, there is a problem that the lens driving device becomes large and a camera-equipped mobile phone using the lens driving device becomes thick and large.

  In addition, since it is necessary to accurately incorporate the two elastic members into a predetermined position of the lens driving device, if the assembly position of the elastic member to the lens driving device is shifted, the reaction force center position of each elastic member is shifted. Twisting occurs and the moving direction of the movable lens barrel is distorted. As a result, there is also a problem that the lens in the movable lens barrel moves in a direction inclined with respect to the optical axis direction of the lens.

  In consideration of the above-described points, the present invention provides a lens driving device and a camera-equipped mobile phone that are small and thin and have a stable movement of a movable lens barrel.

  A lens driving device according to the present invention includes a movable lens barrel having a lens, a drive mechanism that moves the movable lens barrel in the optical axis direction of the lens, and a fixed holder that houses the movable lens barrel and the drive mechanism. The lens driving device includes a single elastic member that movably holds the movable barrel.

The lens driving device according to the present invention, the movable lens barrel having a lens, and a coil attached to the variable movement barrel, a yoke coils is arranged to be inserted, attached to the yaw click Te, Ru comprising a magnet constituting a magnetic circuit together with the yaw click, a fixed holder for accommodating a variable dynamic barrel, a single elastic member for connecting the fixing holder, the.
Furthermore, the elastic member is a rectangular frame that holds the movable barrel movably, and a holding frame that is located inside the same plane as the rectangular frame and holds the lower end of the movable barrel. And a connecting body having a meandering shape portion on the holding frame body side and linearly connecting the rectangular frame body corner portion and the holding frame body in the radial direction.

  Preferably, the upper portion of the yoke and the upper portion of the fixed holder of the lens driving device according to the present invention are substantially the same height, and the upper portion of the movable barrel protrudes from the upper portion of the fixed holder; To do.

  More preferably, the elastic member of the lens driving device according to the present invention is arranged in the vicinity of the center of gravity of the movable barrel.

  In the lens driving device according to the present invention, the height of the lens driving device is reduced and the lens driving device is made thin.

  The camera-equipped mobile phone according to the present invention is a camera-equipped mobile phone having a lens driving device and display means for displaying an image obtained by the lens driving device, the lens driving device having a lens. A lens driving device comprising: a lens barrel; a drive mechanism that moves the movable lens barrel in the optical axis direction of the lens; and a fixed holder that houses the movable lens barrel and the drive mechanism. It is set as the structure which has the single elastic member which hold | maintains a lens barrel so that a movement is possible.

  In the camera-equipped mobile phone of the present invention, since the height of the lens driving device is lowered, the camera-equipped mobile phone using the lens driving device can be reduced in size.

  According to the lens driving device of the present invention, a small and thin lens driving device can be obtained.

  The camera-equipped mobile phone according to the present invention can be a small and thin camera-equipped mobile phone.

  Hereinafter, examples of the best mode for carrying out a lens driving device and a camera-equipped mobile phone according to the present invention will be described with reference to the drawings. However, the present invention is not limited to the following examples. Although this embodiment has a configuration suitable for mounting as a camera part of a mobile phone, it may be mounted on another mobile device such as a PDA (Personal Degital Assistance).

FIG. 1 is an exploded perspective view of a lens driving device according to an embodiment of the present invention.
As shown in FIG. 1, the lens driving device 1 according to this example includes a movable barrel 10, a driving coil 14, a yoke 15, a driving magnet 18, an elastic member 19, and a fixed holder 20. Yes.

  The movable lens barrel 10 has a plurality of lenses therein, and a lens holder 26 is provided. The lens holder 26 includes a cylindrical portion 26a that holds the lens and a flange portion 26b for attaching and fixing the drive coil 14.

  The drive coil 14 is a cylindrical coil having an air core in which a single wire is wound in a plurality of layers, and is bonded and fixed to the flange portion 26b in a state where the cylindrical portion 26a of the movable lens barrel 10 is inserted into the air core. The

  The yoke 15 has a U-shaped ring shape having an inner diameter and an outer diameter, and has a downward opening. A cylindrical portion 26 a of the movable lens barrel 10 is inserted in the center of the yoke 15, and a drive coil 14 attached to the movable lens barrel 10 is inserted inside the yoke 15.

  The drive magnet 18 has a ring shape, and is fixedly disposed along the inside of the outer peripheral wall surface of the yoke 15.

  The elastic member 19 is composed of a single flat elastic plate. The elastic plate includes a fixed portion 19a formed by a rectangular frame for connecting to the fixed holder 20, a fixed portion 19b formed by a ring-shaped frame for connecting to the lower end portion of the movable lens barrel 10, and a movable plate. It is comprised by the elastic part 19c which has the elasticity which makes the lens-barrel 10 movable. The elastic portion 19c has a so-called meandering shape portion, and is configured to connect the fixed portion 19a and the fixed portion 19b.

  The fixed holder 20 includes a substantially square bottom portion and a peripheral wall portion along the bottom portion, and has an opening upward. The fixed holder 20 accommodates the movable lens barrel 10, the yoke 15, and the elastic member 19 therein.

FIG. 2 is a perspective view when a broken line is put in the fixed holder of the lens driving device according to the embodiment of the present invention.
As shown in FIG. 2, the movable holder 10, the yoke 15, and the elastic member 19 are accommodated in the fixed holder 20.

  The lower part of the movable lens barrel 10 is supported by a single elastic member 19 having four elastic portions 19c. Here, single means that there is only one elastic member 19 provided in the fixed holder 20. The fixing portion 19b of the elastic member 19 is fixed along the inner wall of the fixing holder 20 with an adhesive or the like. The movable lens barrel 10 is supported so that the upper portion of the cylindrical portion 26 a of the movable lens barrel 10 protrudes from the upper portion of the yoke 15.

  The yoke 15 has a cylindrical portion 26a of the movable lens barrel 10 inserted in the center, and a drive coil 14 fixed to the flange portion 26b of the movable lens barrel 10 on the inner side. It is bonded and fixed to a part. A drive magnet 18 is fixed inside the yoke 15 so as to face the drive coil 14.

FIG. 3 is a sectional view of the lens driving device according to the embodiment of the present invention.
As shown in FIG. 3, the lens driving device 1 mainly includes a movable lens barrel 10 and a drive mechanism that moves the movable lens barrel 10 along the optical axis direction F of the lens 12 indicated by an arrow in the drawing. (The drive coil 14 and the drive magnet 18) and a fixed holder 20 having a role as a case for housing them.

  Inside the movable lens barrel 10, a lens 12 and an intermediate member 28 as a spacer are disposed.

  The lens 12 is a photographing lens of a camera and is configured by combining a plurality of lens members. The upper side (front side of the lens driving device 1) in FIG. 2 is the subject side lens member 12a, and the lower side (rear side of the lens driving device 1) is the camera body side lens member 12b. In the lens driving device 1 of the present example, the movable lens barrel 10 is composed of a plurality of members, that is, the lens 12, the resin lens holder 26, and the intermediate member 28. The member may be comprised integrally with the same member.

  The subject-side lens member 12a has a circular lens portion having a lens function at the center, and a holder portion (not shown) for holding and supporting the lens portion on the outer periphery. The holder portion is in contact with the intermediate member 28. The camera body side lens member 12b has a lens portion having a lens function in the center and a holder portion (not shown) for holding and supporting the lens portion on the outer periphery. The holder portion of the camera body side lens member 12b is also in contact with the intermediate member 28.

  The lens portions of the subject side lens member 12a and the camera body side lens member 12b are resin aspheric lenses, and the holder portion and the lens portion are formed by integral molding of resin. The lens holder 26 includes a cylindrical portion 26a and a flange portion 26b. Further, the presence of the intermediate member 28 simplifies the attachment work and positioning work of the lens 12.

  The cylindrical portion 26a of the lens holder 26 has a bottomed cylindrical shape, and the lens 12 is fitted in the cylindrical portion 26a. In addition, a circular incident window 36 for taking reflected light from the subject into the lens 12 is formed on the front surface of the cylindrical portion 26a of the lens holder 26.

  The flange portion 26b of the lens holder 26 is formed on the lower side of the cylindrical portion 26a, and has a disk shape along the outer periphery of the cylindrical portion 26a. The drive coil 14 is placed and fixed on the collar portion 26b.

  The intermediate member 28 is a disk-shaped member having a hole 34 in the center. The intermediate member 28 keeps the distance between the subject side lens member 12a and the camera body side lens member 12b constant.

  The drive mechanism for moving the movable lens barrel 10 in the optical axis direction F of the lens 12 is an electromagnetic attraction force or electromagnetic repulsion between the drive coil 14 wound around the optical axis F and the drive coil 14. The drive magnet 18 is an electromagnetic member that generates force.

  The drive coil 14 is fixed so as to be placed on the flange portion 26 b of the lens holder 26, and the upper portion of the drive coil 14 is disposed so as to be inserted inside the yoke 15.

The drive magnet 18 has a ring shape, is fixed along the inside of the outer peripheral surface of the yoke 15, and is held so as to be positioned around the cylindrical portion 26 a of the movable lens barrel 10.
That is, the drive magnet 18 is disposed inside the yoke 15 so as to face the drive coil 14, and constitutes a magnetic circuit in the lens drive mechanism.

  A single elastic member 19 that holds the movable lens barrel 10 so as to be movable is disposed below the movable lens barrel 10. The elastic member 19 is attached to the inner side surface of the fixed holder 20 and the rear end portion of the cylindrical portion 26 a of the lens holder 26 so as to connect the fixed holder 20 and the movable lens barrel 10. The elastic member 19 of this example is arranged in one plane in the fixed holder 20, and here, “in one plane” means a surface having the same height in the fixed holder 20.

  In this example, the elastic member 19 is arranged below the magnetic circuit constituted by the drive coil 14 and the drive magnet 18, but the elastic member 19 may be arranged above the magnetic circuit. Good.

  Further, in the lens driving device 1 of the present example, as shown in FIG. 3, the end surface formed on the upper portion of the fixed holder 20 and the end surface formed on the upper portion of the yoke 15 have substantially the same height. Is configured. Further, the upper end surface of the movable lens barrel 10 is held by the elastic member 19 in a state of protruding from the surface formed by the yoke 15 and the upper end surface of the fixed holder 20. That is, a space S as indicated by a broken line is formed above the surface formed by the yoke 15 and the fixed holder 20.

  An image sensor unit (not shown) having a filter, an image sensor, and the like is disposed on the rear side along the optical axis F of the lens driving device 1.

  According to the lens driving device 1 of this example, since the movable barrel 10 is held by the single elastic member 19, it is not necessary to use a plurality of elastic members, and the lens driving device 1 is made small and thin. Can do. Moreover, since the space space S can be formed above the yoke 15 and the fixed holder 20, the lens driving device 1 can be reduced in size and thickness by the amount of the space.

  Further, according to the lens driving device of the present example, since the movable lens barrel 10 is held by a single elastic member, distortion in the moving direction of the movable lens barrel 10 that occurs when a plurality of elastic members are used is prevented. In addition, the moving operation of the movable lens barrel can be stabilized. Furthermore, since the movable barrel 10 is held by a single elastic member, it is not necessary to use a plurality of elastic members, and costs can be reduced.

  In addition, by increasing the thickness of the elastic portion 19c of the elastic member 19, by increasing the spring constant of the elastic member 19, the movement operation of the movable lens barrel 10 can be stabilized without significantly changing the resonance frequency of the movable lens barrel 10. Can be made.

FIG. 4 is a cross-sectional view of a lens driving device according to another embodiment of the present invention. 4, parts corresponding to those in FIG. 3 are denoted by the same reference numerals and description thereof is omitted.
As shown in FIG. 4, a guide shaft 21 protruding in the optical axis direction is formed at the bottom of the fixed holder 20. Further, a portion extending in the direction in which the guide shaft 21 is provided is formed in a part of the flange portion 26 b of the lens holder 26.

  A hole for inserting the guide shaft 21 is formed in the extended portion of the flange portion 26b. The size of the formed hole is such that the movable barrel 10 can freely move along the guide shaft 21.

  According to the lens driving device 1 of this example, since the guide shaft 21 that assists the movement of the movable lens barrel 10 is provided, the guide shaft 21 is movable even when the camera function is used in an unstable posture. Since the posture of the lens barrel 10 can be kept constant, the movable lens barrel 10 can be prevented from being tilted from the optical axis direction. As a result, even when the camera function is used in an unstable posture, the movable lens barrel 10 does not tilt from the optical axis direction, so that it is possible to prevent deterioration in optical performance such as deterioration in resolution. it can.

  FIG. 5 is a perspective view when a broken line is put in a fixed holder of a lens driving device according to another embodiment of the present invention. In FIG. 5, parts corresponding to those in FIG.

  As shown in FIG. 5, a plurality of notches 15a are formed in a part of the outer peripheral wall of the yoke 15 so as to correspond to the arm portion of the elastic member 19 including the elastic portion 19c. Since the elastic member 10 of this example has four arms according to the number of corners of the fixed holder 20, the notches 15a formed in the yoke 15 are formed in four places. The A plurality of notches are also formed on the inner peripheral wall side of the yoke 15 at positions facing the notches 15a provided on the outer peripheral wall side.

  The magnet 18 is provided along the inner side of the outer peripheral wall of the yoke 15 excluding the portion where the notch 15a is provided.

  The elastic member 19 has a fixing portion 19a fixed to the inner peripheral surface of the fixing holder 20, and an arm portion including the elastic portion 19c is sandwiched between two coils 14 formed inside the yoke 15, thereby fixing the fixing portion 19b. Is fixed to the movable barrel 10 along the outer periphery of the cylindrical portion 26a.

  FIG. 6 is a cross-sectional view of a lens driving device according to another embodiment of the present invention. In FIG. 6, parts corresponding to those in FIG.

  As shown in FIG. 6, the elastic member 19 of this example is disposed near the position of the center of gravity g of the movable barrel 10. That is, the elastic member 19 is provided along a plane including a point where the center of gravity g of the movable lens barrel 10 is located. In other words, in the fixed holder 20, the elastic member 19 is attached to the fixed holder 20 so that the height at which the center of gravity g of the movable lens barrel 10 is located and the height at which the elastic member 19 is located are the same height. .

  The drive coil 14 is formed by being divided into two in the vertical direction. The height of the divided downward coil is such that the center of gravity g of the movable lens barrel 10 is attached to the flange 26b of the lens holder. Is formed so as to coincide with the height of a plane including Further, the yoke 15 is provided with a notch at a position corresponding to the height of the plane including the center of gravity g of the movable lens barrel 10.

  The single elastic member 19 is disposed in the same plane in the fixed holder 20. The fixing portion 19a of the elastic member 19 is attached to the fixing holder 20, and the arm portion including the elastic portion 19c passes through the notch portions provided in the yoke 15 and the driving magnet 18, and the divided driving coil 14 is provided. The fixed portion 19b is connected to the cylindrical portion 26a of the movable barrel 10 through the gap. That is, the lens driving device 1 of the present example has a configuration in which a part of the magnetic circuit is divided and the elastic member 19 is penetrated. The movable lens barrel 10 is suspended from the fixed holder 20 by the elastic member 19 at the center of gravity g.

  According to the lens driving device 1 of this example, since the single elastic member 19 is disposed in the vicinity of the center of gravity g of the movable barrel 10, the movable barrel 10 is fixed at the center of gravity g of the movable barrel 10. 20 can be hung. Therefore, even when the camera function is used in an unstable posture, the elastic member holds the center of gravity g of the movable lens barrel 10, and thus the movable lens barrel is prevented from being inclined with respect to the optical axis. be able to. As a result, even when the camera function is used in an unstable posture, the movable lens barrel 10 does not tilt from the optical axis direction, so that it is possible to prevent deterioration in optical performance such as deterioration in resolution. it can.

FIG. 7 is a perspective view of the camera-equipped mobile phone when the lens driving device according to the present invention is attached.
As shown in FIG. 7, the camera-equipped mobile phone 100 includes a main body portion 101 on which operation buttons are arranged, and a cover portion 102 in which a portion for displaying an image photographed by the camera is formed on the back surface. By sliding or folding the cover portion 102 so as to match the main body portion 101, a compact size convenient for carrying can be achieved. When shooting using the camera function, as shown in FIG. 8, the main body 101 and the cover 102 are used in a shifted state.

  A hole for embedding the lens driving device 1 is formed in the back surface portion of the cover portion 102 of the camera-equipped mobile phone 100. The lens driving device 1 is attached to the hole so that the incident window 36 formed in the lens holder 26 faces outward.

  According to the camera-equipped mobile phone 100 of this example, since the thin lens driving device 1 is used, the thickness of the cover portion 102 can be reduced. As a result, when the main body 101 and the cover 102 are matched, the overall thickness of the camera-equipped mobile phone can be reduced, so that the camera-equipped mobile phone 100 can be made smaller and thinner. In addition, since the components of the mobile phone 100 can be arranged in the space S formed on the yoke 15 and the fixed holder 20 of the lens driving device 1, the camera-equipped mobile phone 100 can be reduced in thickness and size. be able to.

  Next, a system configuration of the camera 120 of the camera-equipped mobile phone 100 including the lens driving device 1 will be described with reference to FIG.

  The camera 120 saves image data by a driver 122 that drives a movable lens barrel 10 having a lens 12 to realize a switching operation, an ISP (Image Signal Processor) 124 that processes an image signal obtained from the image sensor 104, and the like. Storage device 126, control logic unit 128, one or more memories 130 for temporarily storing images for electronic processing, display means 132 for displaying optical images and electronic processed electronic images, An MPU (Micro Processing Unit) 134 is provided as a system controller for controlling each member.

  Here, the camera 120 includes a mechanical portion of the lens driving device 1 including the movable lens barrel 10 having the lens 12, the image sensor 104, a driver 122, and an ISP 124. The image sensor 104, the driver 122, and the ISP 124 are installed on the circuit board 106. The control unit includes a control logic unit 128 and an MPU 134. Further, the image acquisition unit includes the image sensor 104, the ISP 124, and a control unit. The MPU 134 serves as a switching command reading unit that reads a switching command, serves as an operation position confirmation unit that confirms the operation position of the lens 12, and also serves as a current position detection unit that detects the position of the lens 12.

  In the state shown in FIG. 3, when a predetermined changeover switch (not shown) is operated, a current flows through the drive coil 14 via the elastic member 19. Then, a force acts on the drive magnet 18 according to Fleming's left-hand rule depending on the direction of the current and the direction of the magnetic field generated by the drive magnet 18. In this example, since the drive magnet 18 is fixed to the yoke 15 and the yoke 15 is fixed to the fixed holder 20, a force acts on the drive coil 14 as a reaction. Thereby, the movable lens barrel 10 moves in the optical axis direction F by the elastic force of the elastic member 19. Note that Fleming's left-hand rule indicates the relationship between forces acting on an object that is carrying a line current when a line current flows in the magnetic field.

  In the above-described embodiment, the drive mechanism is configured by the drive magnet 18 and the drive coil 14. However, the drive magnet is disposed at the position of the drive coil, and the drive coil is disposed at the position of the drive magnet. It may be a so-called moving magnet drive.

  Further, in the present embodiment, the example in which the lens driving device 1 is incorporated as a function of the camera portion of the camera-equipped mobile phone 100 has been described. It can be used or incorporated into other camera devices such as surveillance cameras and medical cameras, and electronic devices such as automobiles and televisions.

FIG. 1 is an exploded perspective view of a lens driving device according to an embodiment of the present invention. FIG. 2 is a perspective view when a broken line is put in the fixed holder of the lens driving device according to the embodiment of the present invention. FIG. 3 is a sectional view of the lens driving device according to the embodiment of the present invention. FIG. 4 is a cross-sectional view of a lens driving device according to another embodiment of the present invention. FIG. 5 is a perspective view when a broken line is put in a fixed holder of a lens driving device according to another embodiment of the present invention. FIG. 6 is a cross-sectional view of a lens driving device according to another embodiment of the present invention. FIG. 7 is a perspective view of the camera-equipped mobile phone when the lens driving device according to the present invention is attached. FIG. 8 is a schematic diagram showing a system configuration of a camera including the lens driving device according to the embodiment of the present invention.

Explanation of symbols

1 .... Lens driving device, 10 .... Moving barrel, 12 .... Lens, 14 .... 1 Driving coil, 15 .... Yoke, 18 .... Driving magnet, 19 .... Elastic member, 20 .... Fixed holder, 21 .... ..Guide shaft 26..Lens holder 28..Intermediate member 34..Hole 36..Incoming window 100..Mobile phone with camera, F..Optical axis direction, g..Moveable barrel center of gravity , S. Space

Claims (6)

A movable barrel having a lens, a drive mechanism for moving the movable barrel in the optical axis direction of the lens, a fixed holder for housing the movable barrel and the drive mechanism, and for connecting the fixed holder A single elastic member ,
The elastic member includes a quadrangular frame that holds the movable barrel movably ,
A holding frame for holding the lower end of the movable lens barrel, located inside the same plane as the rectangular frame,
The rectangular frame body corner and the holding frame are linearly connected in a radial direction, and a connecting body having a meandering shape portion on the holding frame side;
A lens driving device. A movable lens barrel having a lens;
A coil attached to the movable barrel;
A yoke arranged so that the coil is inserted;
A magnet that is attached to the yoke and forms a magnetic circuit together with the yoke;
A fixed holder for storing the movable barrel; and a single elastic member for connecting the fixed holder ;
The elastic member includes a quadrangular frame that holds the movable barrel movably ,
A holding frame for holding the lower end of the movable lens barrel, located inside the same plane as the rectangular frame,
The rectangular frame body corner and the holding frame are linearly connected in a radial direction, and a connecting body having a meandering shape portion on the holding frame side;
A lens driving device.   2. The lens drive according to claim 1, wherein an upper portion of the yoke and an upper portion of the fixed holder have substantially the same height, and an upper portion of the movable barrel protrudes from an upper portion of the fixed holder. apparatus.   The lens driving device according to claim 2, further comprising an auxiliary member for assisting movement of the movable barrel. The lens driving device according to claim 1, wherein the elastic member is disposed in the vicinity of the center of gravity of the movable barrel. A lens driving device and display means for displaying an image obtained by the lens driving device ,
The lens driving device includes:
A movable lens barrel having a lens;
A drive mechanism for moving the movable lens barrel in the optical axis direction of the lens;
A fixed holder that houses the movable barrel and the drive mechanism, and a single elastic member for connecting the fixed holder ,
The elastic member includes a quadrangular frame that holds the movable barrel movably ,
A holding frame for holding the lower end of the movable lens barrel, located inside the same plane as the rectangular frame,
The rectangular frame body corner and the holding frame are linearly connected in a radial direction, and a connecting body having a meandering shape portion on the holding frame side;
The camera-equipped mobile phone equipped with.

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