KR100899063B1 - Lens drive device, imaging device, and lens position adjustment method for imaging device - Google Patents

Abstract

The lens drive device 10 includes a lens frame 3 holding a small diameter lens 2a and a large diameter lens 2b. The guide shaft 4 is slidably engaged with the guide hole 35 in the optical axis direction formed in the lens frame 3. The driving coil 5 can be wound in the coil holding part 34 formed adjacent to the small diameter frame part 31 holding the small diameter lens 2a among the lens frames 3. The magnet 7 is arrange | positioned so that the coil 5 may be pinched | interposed with the guide shaft 4. The guide shaft 4 is fixed to the yoke 6, and the yoke 6 and the guide shaft 4 constitute a part of the magnetic circuit including the magnet 7. By fixing the coil 5 to the coil holding part 34 adjacent to the small diameter frame part 31 of the lens frame 3, the dimension of the lens drive device 10 is reduced, and as a result, the lens drive device. The miniaturization and weight reduction of (10) can be realized.

Description

LENS DRIVE DEVICE, IMAGING DEVICE, AND LENS POSITION ADJUSTMENT METHOD FOR IMAGING DEVICE}

The present invention relates to a lens driving device for moving a lens along an optical axis, an imaging device using the same, and a method of adjusting the lens position.

Background Art Conventionally, in imaging devices such as miniature cameras, a DC motor or a stepping motor has been used as an actuator for moving a lens in the optical axis direction. However, in recent years, the use of mounting an imaging device in a portable device is increasing, and the request for downsizing and weight reduction of an imaging device is high, and accordingly, the size and weight of a lens drive device are calculated | required.

Here, a so-called voice coil motor in which a coil is disposed in a magnetic circuit made of a magnet or a yoke in place of a DC motor or the like has recently been used. In the lens drive apparatus using such a voice coil motor, in order to reduce the lens frame as a movable part as much as possible, it is proposed to wind the coil in the lens frame and to arrange the magnet and the yoke in the fixing portion (for example, Patent Document 1). , 2, 3). Specifically, winding the coil so as to wind up the entire circumference of the lens frame (for example, refer to Patent Document 1), or winding the coil (for example, see Patent Documents 2 and 3) to the protrusion provided in the lens frame. It is.

On the other hand, in order to eliminate the wiring clutter when winding a coil to the lens frame which is a movable part, it is also proposed to fix a magnet to a lens frame and to wind a coil to a fixed part (for example, refer patent document 1, 4). . Moreover, it is also proposed to simplify an apparatus structure by using the guide axis which guides a lens frame to an optical axis direction as a part of yoke (for example, refer patent document 5).

Patent Document 1: Japanese Patent Laid-Open No. 1994-201975 (3rd to 4th pages, FIGS. 10 to 12)

Patent Document 2: Japanese Patent Application Laid-Open No. 2000-137156 (Page 4, Fig. 2)

Patent Document 3: Japanese Patent Laid-Open No. 2002-350716 (Page 4, Fig. 3)

Patent Document 4: Japanese Patent Laid-Open No. 2000-321475 (Second page, Fig. 2)

Patent Document 5: Japanese Patent Application Laid-Open No. 1987-88147 (3rd page, FIG. 5)

Here, in a portable device with a camera or the like, a display portion such as a liquid crystal monitor and a camera (imaging element) are generally disposed adjacently, but in such an arrangement, the length of the display portion and the camera adjacent to each other (for example, a vertical direction) It is required to keep it as short as possible. However, as disclosed in Patent Literature 1, the coil is wound so as to wind the entire circumference of the lens frame, and the magnet and the yoke are disposed so as to face the coil, so that the device dimensions are increased over the entire circumference of the lens frame. There is a problem.

In addition, as disclosed in Patent Literatures 2 and 3, even if the coil is wound around the projection of the lens frame or the like, a space for accommodating the flexible printed circuit board for performing energization to the coil must be provided around the lens frame. Also, there is a problem that the device dimensions of the lens driving apparatus become large.

In addition, as disclosed in Patent Literatures 1 and 4, when the magnet is fixed to the lens frame as the movable portion, the weight of the lens frame is increased, which causes a problem that the driving current required for driving the lens frame is increased. In addition, as the weight of the lens frame increases, the frictional resistance between the guide shaft guiding the lens frame and the bearing portion also increases, and as a result, the required driving current becomes larger.

In addition, as disclosed in Patent Literature 5, when a guide shaft for guiding the lens frame in the optical axis direction is used as the yoke of the magnetic circuit, the coil is arranged so as to wind the guide shaft, but the lens and the coil do not interfere with each other. In order to prevent this, the distance between the guide shaft and the lens must be kept relatively long, and there is a problem that the dimension in the longitudinal direction of the lens frame becomes large.

SUMMARY OF THE INVENTION The present invention is carried out to solve the above problems, and an object thereof is to reduce the size and weight of the lens driving apparatus.

A lens driving device according to the present invention is a lens group including a first lens and a second lens having a larger outer diameter than the first lens, and a lens frame for holding the lens group, which is substantially parallel to the optical axis direction of the lens group. And a fixing part including a lens frame having a guide hole formed so as to be slidable, a guide part slidably engaged with the guide hole and guiding the lens frame in the optical axis direction, and fixed to wind the guide axis to the lens frame. A coil, a magnet fixed to the coil between the guide shaft and the guide shaft, and a yoke constituting a part of a magnetic circuit including the magnet together with the guide shaft, wherein the lens The coil is arranged so as to be adjacent to the portion holding the first lens of the frame.

According to the present invention, the coil is wound around the guide shaft, and the coil is disposed adjacent to the portion holding the small diameter first lens in the lens frame, so that the distance between the optical axis and the guide shaft is shortened. And interference with the coil can be avoided, and as a result, the dimension of the lens driving apparatus can be reduced. That is, the size and weight of the lens driving device can be realized.

Embodiment 1

1 is a plan view showing a lens driving apparatus 10 according to Embodiment 1 of the present invention. FIG. 2: is sectional drawing (YZ sectional drawing) of the lens drive apparatus 10 in the II-II line shown in FIG. This lens drive device 10 can be used as an autofocus mechanism (autofocus mechanism) of a short focal length lens in an imaging device (for example, a small camera mounted in a mobile phone). Specifically, the lens driving device 10 moves the lenses 2a and 2b (FIG. 2) along the optical axis A, and forms an image of the subject on the solid-state imaging element 91 (FIG. 2).

1 and 2, the direction of the optical axis A (FIG. 2) of the lenses 2a and 2b is set as the Z direction, and one direction in the plane perpendicular to the optical axis A (FIGS. 1 and 2). The left-right direction in 2) is called Y direction. In addition, the direction orthogonal to the Y direction in surface inside orthogonal to the optical axis A is called X direction. In the Z direction, the direction toward the subject is made upward (that is, the + Z direction), and the direction toward the solid-state imaging element 91 is made downward (that is, the -Z direction).

 Among the lenses 2a and 2b, the outer diameter of the upper lens 2a (called the small diameter lens 2a) is smaller than the outer diameter of the lower lens 2b (called the large diameter lens 2b). The lens drive device 10 has a lens frame 3 for holding the lenses 2a and 2b. This lens frame 3 has substantially ring-shaped frame portions 31 and 32 holding the lenses 2a and 2b, respectively. The outer diameter of the large diameter frame portion 32 holding the large diameter lens 2b is larger than the outer diameter of the small diameter frame portion 31 holding the small diameter lens 2a. The frame parts 31 and 32 are formed so that each center may overlap with the optical axis A so that each center may correspond with the optical axis A. FIG.

 The lens frame 3 has the support part 33 integrally formed so that the frame part 31 and 32 may be adjacent to the Y direction (radial direction of the lens 2a, 2b). This support part 33 has a shape long in the Y direction. The guide hole 35 penetrates through the support part 33 of the lens frame 3 in the Z direction, and the guide shaft 4 penetrates slidably through this guide hole 35. The lower end of the guide shaft 4 is fitted to the hole of the yoke 6 fixed to the housing 11 of the imaging device.

 By sliding between the guide shaft 4 and the guide hole 35, the lens frame 3 is movable in the Z direction along the guide shaft 4. In order to define the movable range of the lens frame 3 in the Z direction, the lens frame 3 is not shown at each of the positions contacted when reaching the movement limit in the + Z direction and the movement limit in the -Z direction. A stopper is provided. The yoke 6 and the guide shaft 4 are each formed of a magnetic material, and constitute a magnetic circuit (described later) including the magnet 7. In addition, the guide shaft 4 should just fit the yoke 6 in the range which can pass the magnetic force line of the magnet 7. As shown in FIG.

On the upper side of the support part 33 of the lens frame 3, the coil holding part 34 is formed so that it may adjoin in the Y direction with respect to the small diameter frame part 31 which hold | maintains the small diameter lens 2a. The coil 5 is wound around the coil holding part 34 so that the circumference | surroundings of the guide shaft 4 may be wound up. The coil 5 is wound in a substantially rectangular shape so as to have two sides in the X direction and two sides in the Y direction. In the energization of the coil 5, the configuration described in Embodiment 2 described later may be used, or another configuration may be used.

FIG. 3 is a perspective view showing a part of the lens driving device 10 shown in FIG. FIG. 4 is a rear view of the lens driving device 10 shown in FIG. 1 viewed in the Y direction. The yoke 6 is, for example, a plate-shaped member that is bent in a “co” shape, and includes a bottom portion 63 on which the lower end of the guide shaft 4 is fixed, and both ends of the bottom portion 63 in the X direction. It has wall parts 61 and 62 extending from the upper side. The magnets 7 are attached to the inner surfaces of the wall portions 61 and 62 so as to sandwich the coil 5 in the X direction, respectively. Each magnet 7 opposes the edge extending in the Y direction of the coil 5.

The solid-state imaging element 91 described above is fixed to the housing 11 by attaching a package to the housing 11 with an adhesive or the like. In addition, the circuit board 92 is fixed and electrically connected to the solid-state imaging element 91. In addition, both the solid-state imaging device 91 and the circuit board 92 may be fixed to the housing 11 with an adhesive, or only the circuit board 92 is fixed to the housing 11 with an adhesive, and the solid-state imaging device 91 may be fixed. May be indirectly fixed to the housing 11.

 On the upper surface of the lens frame 3, a magnetic piece 8 made of a magnetic material is fixed so as to be located above the coil 5. This magnetic piece 8 is disposed so that the lens frame 3 is always located on the + Z side (ie, the subject side) rather than the center position of the magnet 7 in the Z direction when the lens frame 3 is in the movable range in the Z direction. .

FIG. 5: is a schematic diagram for demonstrating the magnetic circuit of the lens drive apparatus 10, and respond | corresponds to sectional drawing (XZ sectional drawing) in the IV-IV line | wire of FIG. The two magnets 7 are arranged symmetrically in the X direction with respect to the guide axis 4. Each magnet 7 is magnetized in the X direction so that the surface side fixed to the yoke 6 becomes the N pole, and the side opposite to the coil 5 becomes the S pole. As a result, the variation in the Y direction of the coil 5 is located between the S pole of the magnet 7 and the guide shaft 4. The magnetic lines of force from the north pole of the magnet 7 travel along the wall portions 61 and 62 and the bottom portion 63 of the yoke 6 and also pass through the guide shaft 4, and the coil holding portion 34 and The coil 5 reaches the S pole of the magnet 7. When a current flows through the coil 5, an electromagnetic force in the axial direction (that is, Z direction) of the guide shaft 4 is generated in the coil 5 by the action of the current and the magnetic field caused by the magnet 7. Here, a current flows in the direction in which the electromagnetic force in the + Z direction (upward) is generated in the coil 5.

On the other hand, the magnetic strip 8 is always given a force toward the center position of the magnet 7 in the Z direction (that is, the highest position of the magnetic flux density) by the magnetic field generated by the magnet 7. Since the movable piece of the lens frame 3 is determined so that the magnetic piece 8 will always be located in the + Z direction side (the subject side) rather than the center of the Z direction of the magnet 7, it will always be in the lens frame 3. The pressing force in the -Z direction is acting. In addition, it is preferable that the magnetic piece 8 is comprised from soft magnetic bodies, such as nickel, from a viewpoint of obtaining a large press force.

When an electromagnetic force in the + Z direction is generated by flowing a current in a predetermined direction through the coil 5, the lens frame 3 resists the pressing force in the -Z direction that the magnetic piece 8 receives from the magnet 7, It moves in the + Z direction along the guide axis 4. By changing the current value flowing through the coil 5, the magnitude of the electromagnetic force can be changed, and the lens frame 3 is moved to the guide shaft 4 to a position where the electromagnetic force in the + Z direction and the pressing force in the -Z direction are balanced. You can move according to.

When the current in the coil 5 is stopped, the electromagnetic force in the + Z direction disappears, so that the lens frame 3 is in the -Z direction due to the pressing force in the -Z direction that the magnetic piece 8 receives from the magnet 7. Return to the movement limit (position facing the projecting front not shown).

Here, when the lens frame 3 is at the limit of movement in the -Z direction, light from the infinite object is imaged on the imaging surface of the solid-state imaging element 91 by the lenses 2a and 2b. From this state, rather than moving the lenses 2a and 2b in the + Z direction (the subject side), the solid-state imaging element 91 can form an image of a subject at a closer position. As a result, it is possible to photograph any subject from infinity to a close position by auto focus.

In addition, as shown in FIG. 1, the magnet 7 is superimposed on the upper part of the large diameter frame part 32 (shown with the code | symbol 32a) holding the large diameter lens 2b. However, as shown in FIG. 4, since the gap C slightly larger than the movement amount of the lens frame 3 is formed between the corresponding portion 32a of the large-diameter frame portion 32 and the magnet 7. Even if the lens frame 3 moves in the Z direction, it does not come into contact with the magnet 7.

 Next, the effect by Embodiment 1 is demonstrated. When the coil 5 is wound around the large diameter frame portion 32 or the entirety of the small diameter frame portion 31, the magnet 7 must be disposed so as to face the coil 5. The dimension of the X direction becomes large. In contrast, in the lens drive device 10 according to the present embodiment, as shown in FIG. 1, the coil 5 is wound around the coil holding part 34 adjacent to the small diameter frame part 31. The magnet 7 can be disposed inside the X direction more than the outer diameter of the large-diameter frame portion 32. As a result, the X direction dimension of the lens drive apparatus 10 can be made small. That is, the lens driving apparatus 10 can be miniaturized and reduced in weight.

In addition, in this embodiment, since the coil holding part 34 is formed adjacent to the small diameter frame part 31, when the coil holding part 34 is formed adjacent to the large diameter frame part 32, In comparison, the coil 5 can be arrange | positioned in the position near the optical axis A. FIG. In addition, since a part of the magnet 7 overlaps with the large diameter frame portion 32 in the Z direction, the coil 5 can be further disposed at a position closer to the optical axis A. FIG. As a result, the dimension of the Y direction of the lens drive apparatus 10 can be made further smaller.

In addition, since the pair of magnets 7 are arranged to sandwich the coil 5 in the X direction, the shape of the lens drive device 10 in the Y direction can be further reduced.

In addition, since the restoring force for returning the lens frame 3 to a predetermined position (limit of movement in the -Z direction) can be obtained by the magnetic piece 8 attached to the lens frame 3, the spring It is not necessary to provide a back and the like, and the lens driving apparatus 10 can be further miniaturized. In addition, since the light weight coil is arranged on the movable lens frame 3, the weight of the lens frame 3 can be reduced and the lens frame 3 can be driven with a small current.

In addition, in this embodiment, since it is not necessary to arrange voice coil motor component parts (coil, yoke, magnet, etc.) so that the frame parts 31 and 32 holding the lenses 2a and 2b may be wound, the lens 2a , 2b) can be reduced in size. By miniaturizing and reducing the weight of the lens frame 3 which is a movable part, the difference of the drive current (refer patent document 1, 3) by the posture difference at the time of imaging | photography is also small, and also the guide shaft 4, the guide hole 35, Due to the smaller frictional force, the lenses 2a and 2b can be driven with a smaller driving power.

In addition, in this embodiment, since the guide shaft 4 is used as a part of a magnetic circuit, a projection is provided in the yoke 6 (apart from the guide shaft 4), for example, and the lens frame 3 is provided. ), The lens frame 3 can be further miniaturized as compared with the case where a hole for inserting the projection is formed.

Embodiment 2

6 is a sectional view of YZ showing the lens drive device 20 according to Embodiment 2 of the present invention. FIG. 7 is a perspective view showing a part of the lens drive device 20 shown in FIG. 6 without being cut away. 6 and 7, the same components as those described in Embodiment 1 (FIGS. 1 to 5) are denoted by the same reference numerals. This Embodiment 2 is characterized by the structure of the lead 12 for supplying electric current to the coil 5.

The lead 12 is, for example, a plate-shaped member, and extends downward along the side surfaces of the coil 5 (the surface opposite to the lens 2a and 2b sides) and the side surface of the support portion 33. And the bent portion 12c bent from the lower end of the side portion 12d to the lower side of the lens frame 3 (toward the inside of the coil 5), and returned to a substantially V shape at the tip of the bent portion 12c. Has a return section 12b.

The upper end 13 (FIG. 7) of the side portion 12d is connected to the wire rod 15 of the coil 5 by a conductive method such as soldering. The bent part 12c is bent toward the inner side of the coil 5 from the lower end of the side part 12d extending in the Z direction. The bent portion 12c extends in the substantially Y direction toward the large diameter frame portion 32, and its tip reaches the vicinity of the large diameter frame portion 32. As shown in FIG. The return part 12b is returned downward so as to draw V characters in the YZ plane at the tip of the bend part 12c. The bent part 12c and the return part 12b are accommodated in the space between the bottom part 63 and the support part 33 of the yoke 6. The return part 12b is longer than the bend part 12c, penetrates further through the hole part 11b of the housing 11, and is fixed to this housing 11 by the adhesive agent 11a. The distal end portion 12a of the return portion 12b can be bent downward and connected to a terminal (external terminal) of the circuit board 92 by a conductive method such as mounting through a solder 92a or the like on a connector. have.

In addition, in the structural example shown in FIG. 6 and FIG. 7, although the bending part 12c and the return part 12b were provided below the lens frame 3, you may provide it above the lens frame 3. As shown in FIG. In addition, although the lid 12 does not necessarily need to be fixed to the housing 11, it is preferable that a part of the lid 12 is fixed to a component fixed to the imaging device (that is, not a movable part such as the lens frame 3). .

According to the lens drive device 20 according to the present embodiment, since the lead 12 has the bent portion 12c and the return portion 12b, the bent portion when the lens frame 3 moves in the Z direction. By changing the bending angle of the V between the 12c and the return part 12b by elastic deformation, it is possible to follow the movement of the lens frame 3. Thereby, conduction of the coil 5 and the circuit board 92 can be ensured, while allowing the movement of the lens frame 3 in the Z direction.

In addition, since the deformation of the bent portion 12c and the return portion 12b of the lead 12 is caused by the movement of the lens frame 3, a large force that may interfere with the driving of the lens frame 3 is generated. It is not added to the lens frame 3 from the lid 12. In addition, since a part of the lead 12 is fixed to the housing 11, it is possible to prevent the lead 12 from being inadvertently moved when connecting the lead 12 and the circuit board 92.

In the present embodiment, the coil 5 and the lead 12 are wound by winding the wire 15 of the coil 5 to the frame member and fixing the lead 12 to the wire 15 by soldering or the like. ) Can be assembled (partial assembly) as one part, and assembling property is improved.

In addition, since the side portion 12d extends in the Z direction along the side of the coil 5, and the bent portion 12c and the return portion 12b are located above or below the lens frame 3, the lens is driven. It is not necessary to increase the dimensions of the device 10 in the Y direction or the X direction. That is, the lens drive apparatus 10 can be reduced in size and weight, and the problem that the storage of the lid 12 is difficult (see Patent Document 4) can be solved.

Further, since the tip portion 12a of the lead 12 is bent from the return portion 12b to the circuit board 92 side, the lead 12 can be soldered directly to the circuit board 92. Thereby, the parts score of a wiring component can be reduced. As a result, the fixing strength to the circuit board 92 can be improved by making the width | variety of the lead 12 from the housing 11 to the circuit board 92 wide.

In the above description, although the lead 12 is a plate-shaped member, it is not particularly limited to the plate-shaped member, but may be, for example, a wire rod. In addition, in order to prevent a short circuit between the lead 12, the yoke 6, the magnetic piece 8 and the like, the lead 12 is coated with an insulating coating, or the yoke 6 and the magnetic piece 8 An insulating sheet or the like may be provided on the surface of the substrate.

In addition, in the example shown in FIG. 7, although the bend part 12c and the return part 12b are formed so that it may draw V in the YZ plane, at least one part of the lead 12 is not limited to this structure, What is necessary is just to bend toward the inner side of the coil 5 in the upper side or the lower side of the lens frame 3. For example, as shown in FIG. 8, the bent part 12c and the return part 12b may be formed so that U may be drawn in the surface which inclined the XY plane slightly. In this case, not only the bending part 12c and the return part 12b are spaced apart in the X direction, but also in the Z direction as shown by the arrow H in the figure. When the lens frame 3 is moved in the Z direction, the angle in the YZ plane of the curved portion between the bent portion 12c and the return portion 12b is changed by elastic deformation, so that the lens frame 3 is moved. Can follow the movement of.

Embodiment 3

9 is a sectional view of YZ showing the lens drive device 30 according to Embodiment 3 of the present invention. FIG. 10 is a perspective view showing a movable part of the lens drive device 30 shown in FIG. 9. In FIG. 9 and FIG. 10, the same code | symbol is attached | subjected to the component same as the component demonstrated in Embodiment 1 (FIGS. 1-5) and Embodiment 2 (FIGS. 6-8). This Embodiment 3 is characterized by the structure of the lead 17 for supplying electric current to the coil 5.

In the present embodiment, unlike in the second embodiment, a lead 17 for supplying current to the coil 5 is provided on the + Z direction side (the subject side) of the lens frame 3, and the lens frame 3 is mounted on the lens frame 3. Pressurized in the -Z direction. Due to the configuration in which the lens frame 3 is pressed in the -Z direction by using the lid 7, the magnetic strip 8 (Fig. 2, etc.) is not used in the third embodiment.

The lead 17 is formed of, for example, a spring material, and extends from the upper end of the side portion 17c and the upper side of the side portion 17c along the side of the coil 5 to the upper side of the lens frame 3. It has a bent portion 17b bent (toward the inside of the coil 5) and a return portion 17a that is bent into a substantially V shape at the tip of the bent portion 17b and returned. The lower end 13 of the side part 17c is connected to the coil 5 by the method of conduction, such as soldering. The bent portion 17b is bent toward the inside of the coil 5 from the upper end of the side portion 17c extending in the Z direction. The bent portion 17b extends in the substantially Y direction toward the small diameter frame portion 31, and its tip reaches the vicinity of the small diameter frame portion 31. The return portion 17a is returned to the upper side at the tip of the bent portion 17b so as to draw a V in the YZ plane. The return part 17a is longer than the bend part 17b, and penetrates the hole part 11b of the housing 11, and protrudes further. The tip of the return portion 17a is fixed to the terminal portion (external terminal) of the circuit board 92 via a connection portion (not shown).

The bent portion 17b and the return portion 17a are disposed between the bent portion 17b and the return portion 17a in a space between the upper wall 11c of the housing 11 and the upper surface of the lens frame 3. It is accommodated in the state which elastically deformed so that the V angle | corner of the V shape may become narrow. In this state, the lid 17 tries to elastically deform so that the bending angle of the V between the bent portion 17b and the return portion 17a becomes wider and presses the lens frame 3 in the -Z direction by this elastic force. Doing.

When no current flows in the coil 5, the lens frame 3 is at the limit of movement in the -Z direction due to the pressing force of the lid 17 (that is, in contact with a stopper in the -Z direction). . When the current flows through the coil 5, as described in the first embodiment, the electromagnetic force in the + Z direction is generated by the current in the coil 5 and the magnetic field generated by the magnet 7. The lens frame 3 moves in the + Z direction to the position where the electromagnetic force in the + Z direction and the pressing force in the -Z direction due to the elasticity of the lead 17 are balanced, and the subject image is imaged on the solid-state imaging element 91. do. When the current of the coil 5 is stopped, the lens frame 3 returns to the limit of movement in the -Z direction by the pressing force of the lead 17 in the -Z direction.

As described above, according to the lens driving device 30 according to the present embodiment, since the pressing force of the lens frame 3 is generated by using the elasticity of the lid 17, the magnetic piece 8 (FIG. 2, etc.) It becomes unnecessary. Therefore, in addition to the effects of Embodiment 2 described above, the number of parts can be reduced and the imaging device can be further miniaturized.

Embodiment 4

11 is a rear view of the lens driving device 40 according to Embodiment 4 of the present invention, seen in the Y direction. In FIG. 11, the same code | symbol is attached | subjected to the component same as the component demonstrated in Embodiment 1 (FIGS. 1-5). Embodiment 4 adjusts the relative position with respect to the solid-state image sensor 91 of the lenses 2a and 2b by adjusting the Z direction position of the magnet 7 in an assembly process of an imaging device, etc. .

In the lens drive device 10 (FIGS. 1 to 5) according to the first embodiment described above, the magnetic frame 8 is always positioned at the + Z side of the magnet 7 in the Z-direction center of the magnet 7. The movable range is determined. On the other hand, in the lens drive device 40 according to the present embodiment, the movable range of the lens frame 3 can be positioned so that the magnetic pieces 8 can be located on the + Z side and the -Z side of the Z direction center of the magnet 7. Is fixed.

Since the magnetic piece 8 is pressed toward the Z direction center of the magnet 7 with the highest magnetic flux density, it is the most stable in the state in this Z direction center (referred to as a stable position; C). In other words, when no current flows through the coil 5, the lens frame 3 stops while the magnetic piece 8 is in the stable position C. As shown in FIG. When the magnetic piece 8 has moved from the stable position C to the + Z direction, the magnetic piece 8 is urged in the -Z direction from the magnet 7 in accordance with the movement amount. In addition, when the magnetic piece 8 moves from the stable position C to the -Z direction, the magnetic piece 8 receives a force from the magnet 7 in the + Z direction according to the movement amount. Therefore, by adjusting the position of the magnet 7 in the Z direction (that is, changing the stable position C), the movement range of the lens frame 3 can be moved in the + Z direction or the -Z direction as a whole.

Here, when assembling the imaging device including the lens drive device 40, for example, the magnets 7 of the magnets 7 are used so that the focal planes of the lenses 2a and 2b are exactly aligned with the imaging plane of the solid-state imaging element 91. Adjust the Z direction position. By this adjustment, even if there is a manufacturing error of the lenses 2a and 2b or the solid-state imaging element 91, the focal planes of the lenses 2a and 2b can be exactly matched with the imaging surface of the solid-state imaging element 91. have. In addition, even if the depth of focus becomes severe with the miniaturization of the solid-state image sensor 91, it can respond.

Specifically, in the manufacturing process of the imaging element, the pair of magnets 7 are fixed (temporarily fixed) to the wall portions 61 and 62 of the yoke 6 using magnetic attraction force. In this state, the magnet 7 is moved in the Z direction using the adjusting jig 18 while measuring the position of the focal plane of the lenses 2a and 2b and the like. Here, the magnets 7 are held in the Z direction along the wall portions 61 and 62 while the magnets 7 are magnetically adsorbed to the wall portions 61 and 62 of the yoke 6. Move it. Where the focal planes of the lenses 2a and 2b exactly coincide with the imaging plane of the solid-state imaging device 91, the magnet 7 is fixed (mainly fixed) to the wall portions 61 and 62 using an adhesive. An adhesive may be apply | coated so that the surface fixed to the wall parts 61 and 62 of each magnet 7 may be apply | coated, and you may inject | pour between the magnet 7 and the wall parts 61 and 62. FIG. When the adhesive is injected between the magnet 7 and the wall portions 61 and 62, grooves for pouring the adhesive may be formed in the wall portions 61 and 62.

As described above, according to the fourth embodiment, adjustment of the relative position (focus adjustment) of the solid-state imaging element 91 of the lenses 2a and 2b can be performed by adjusting the Z-direction position of the magnet 7. Therefore, it is not necessary to provide a screw and a ring cam for focus adjustment in the lens frame 3, and as a result, the lens drive device 40 can be further miniaturized.

In addition, although the above-mentioned adjustment jig 18 is prepared separately from an imaging device, you may mount such adjustment jig 18 in an imaging device.

In Embodiments 1 to 4 described above, two lenses 2a and 2b are used, but the number of lenses is not limited to two, but may be three or more. In this case, when the coil 5 is disposed adjacent to a portion of the lens frame 3 that holds a lens other than the lens having the largest diameter, the effect of miniaturization of the lens driving apparatus described above can be obtained.

In addition, although the two magnets 7 were provided in the X direction both sides of the coil 5 in Embodiment 1-4 mentioned above, the number of the magnets 7 is not limited to two, but one side of the coil 5 is carried out. Only one may be provided on the side.

In addition, in Embodiment 2, 3 mentioned above, the lens drive apparatus (coil 5) demonstrated by the structure 1 which bends or curves the lead 12 with respect to the lens frame 3 in one side of a Z direction. Fixed to the coil holding part 34 adjacent to the small-diameter frame part 31 of the lens frame 3, but may be applied to another lens driving apparatus.

In addition, in Embodiment 4 mentioned above, although the adjustment method by adjusting the Z direction position of the magnet 7 is applied to the lens drive apparatus demonstrated in Embodiment 1, it applies to the lens drive apparatus demonstrated in Embodiment 2. You may also In addition, you may apply the adjustment method to lens drive apparatuses other than Embodiment 1, 2.

1 is a plan view of a lens driving apparatus according to Embodiment 1 of the present invention;

2 is a side sectional view of a lens driving apparatus according to Embodiment 1 of the present invention;

3 is a perspective view of a lens driving apparatus according to Embodiment 1 of the present invention;

4 is a rear view of the lens driving apparatus according to Embodiment 1 of the present invention;

5 is a sectional view showing a magnetic circuit of the lens driving apparatus according to Embodiment 1 of the present invention;

6 is a side sectional view of a lens driving apparatus according to Embodiment 2 of the present invention;

7 is a perspective view of a lens driving apparatus according to Embodiment 2 of the present invention;

8 is a perspective view of a lens driving apparatus according to a modification of Embodiment 2 of the present invention;

9 is a side sectional view of a lens driving apparatus according to Embodiment 3 of the present invention;

10 is a perspective view of a lens driving apparatus according to Embodiment 3 of the present invention;

11 is a rear view of the lens driving apparatus according to Embodiment 4 of the present invention.

<Description of the symbols for the main parts of the drawings>

10, 20, 30, 40: lens drive device 2a: small diameter lens

2b: large diameter lens 3: lens frame

31: small diameter frame portion 32: large diameter frame portion

33: support portion 34: coil holding portion

4: guide shaft 5: coil

6: York 61, 62: wall section

63: bottom 7: magnet

8: magnetism 11: housing

12, 17: Lead 12a: Tip

12b, 17a: return part 12c, 17b: bend part

12d, 17c: side 18: adjustment jig

91: solid-state imaging device 92: circuit board

Claims (5)

Lens, A lens frame for holding the lens, the lens frame having a guide hole formed substantially parallel to the optical axis direction of the lens, A fixing portion slidably engaged with the guide hole and including a guide shaft for guiding the lens frame in the optical axis direction; A coil wound around the lens frame so as to surround the guide shaft; A magnet fixed to the fixing part, A yoke constituting part of a magnetic circuit including the magnet, And a conductive member for electrically connecting the coil and an external terminal, The said conductive member is bent inward of the said coil at one side in the said optical axis direction of the said lens frame, and is arrange | positioned in pair so that the said guide shaft may be fitted from both sides, and is connected with the said coil, respectively. By Lens drive device. The method of claim 1, One end of the conductive member is fixed to the coil. Lens drive device. The method according to claim 1 or 2, Further comprising a magnetic piece fixed to the lens frame, By the action of the magnetic piece and the magnet, a pressing force for pressing the lens frame in the optical axis direction is generated. Lens drive device. The method according to claim 1 or 2, The pressing force for pressing the lens frame in the optical axis direction is generated by the elastic force due to the bending of the conductive member. Lens drive device. The lens drive device according to claim 1 or 2, And an image pickup device for taking an image of a subject formed by the lens. Imaging device.

Images