JP2008052196A - Lens driving unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lens driving unit the body of which can be made compact. <P>SOLUTION: The lens driving unit 1 includes a lens-holding means (lens holder 6 and lens case 7) for holding lenses, and a moving mechanism for moving the lens-holding means, along the optical axis direction. The moving mechanism is constituted of an electromagnetic actuator that includes a magnet 10, a coil 9 and a yoke 11, is operated with the power supply to the coil 9, and a storing part 16 for partly storing the electromagnetic actuator (e.g. coil 9) is formed on the outer surface of the lens-holding means. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a lens driving device, and more particularly to a lens driving device suitable for an autofocus function and a camera shake correction function in a digital camera.

In recent years, digital cameras and camera-equipped mobile phones have been miniaturized, and accordingly, lens driving devices used in camera modules are also required to be miniaturized. In order to meet such a demand for downsizing of the lens driving device, for example, the rotation axis of the actuator is arranged in a direction orthogonal to the optical axis of the lens group, so that the device can be thinned in the optical axis direction. A lens driving device has been proposed (see, for example, Patent Document 1).
JP-A-11-64705

  However, the conventional lens driving device described above employs a configuration in which the actuator is disposed on the side of the lens holder formed in a cylindrical shape. Therefore, there is a problem that the apparatus becomes larger in the width direction.

  The present invention has been made in view of such problems, and an object of the present invention is to provide a lens driving device capable of downsizing the apparatus main body.

  The lens driving device of the present invention is a lens driving device including a lens holding unit that holds a lens, and a moving mechanism that moves the lens holding unit along an optical axis direction, the moving mechanism including a magnet, An electromagnetic actuator comprising a coil and a magnetic body and operating by energizing the coil is formed, and an accommodating portion for accommodating a part of the electromagnetic actuator is formed on the outer surface of the lens holding means.

  According to the lens driving device, since the accommodating portion that accommodates a part of the electromagnetic actuator is formed on the outer surface of the lens holding unit, the width of the apparatus main body is prevented from increasing according to the width of the electromagnetic actuator. Therefore, it is possible to reduce the size of the apparatus main body. In addition, since a part of the electromagnetic actuator is housed in the housing part formed on the outer surface of the lens holding means, it is possible to prevent the center position of the apparatus body from deviating from the center position of the lens held by the apparatus. It becomes possible to do.

  In particular, in the lens driving device, the electromagnetic actuator includes an annular magnet and a coil wound in an annular shape, and the housing portion has a shape corresponding to the shape of the magnet or coil. Is preferred. Thus, since the accommodating portion is provided in a shape corresponding to the shape of the magnet or coil having an annular shape, and the magnet or coil is accommodated in this accommodating portion, the main body of the apparatus is effectively utilized while using a limited space. Can be miniaturized.

  For example, in the lens driving device, the magnet is fixed to the lens holding unit, and the coil is fixed to the outside of the lens holding unit so as to face the magnet, and the magnet is lighted by energizing the coil. It is preferable to move in the axial direction. In this case, since the lens holding means can be moved in accordance with the movement of the magnet, the lens holding means can be moved in the optical axis direction by energizing the coil.

  In the lens driving device, the coil is fixed to the lens holding unit, and the magnet is fixed to the outside of the lens holding unit so as to face the coil, and the coil is lighted by energizing the coil. You may make it move to an axial direction. In this case, since the lens holding means can be moved in accordance with the movement of the coil, the lens holding means can be moved in the optical axis direction by energizing the coil.

  In the lens driving device, it is preferable that the lens holding means is attached to the device housing by a leaf spring. In this case, since the urging force by the leaf spring always acts on the lens holding means, the lens holding means can be stabilized even when moving in the optical axis direction in response to the energization of the coil. In particular, it is preferable to attach the lens holding means to the apparatus housing with a plurality of leaf springs. In this case, since the lens holding means can be attached at a plurality of locations and the urging force acting on the lens holding means can be increased, the lens holding means can be made more stable.

  In particular, in the lens driving device, it is preferable to energize the coil via the leaf spring. In this case, since the coil is energized via the leaf spring, no wiring for energizing the coil is required, and the configuration in the lens driving device can be simplified.

  In the lens driving device, the lens holding unit includes a lens case that houses a plurality of lenses having different shapes along the optical axis direction, and the lens case is housed in the lens case. It is preferable to have a shape corresponding to the outer shape of the lens. In this case, since the lens case is provided in a shape corresponding to the outer shape of the plurality of lenses housed therein, the size of the lens holding means can be prevented from becoming unnecessarily large. In an imaging apparatus or the like incorporating a lens holding unit, it is possible to secure a space for arranging other members, moving mechanisms, and the like. As a result, it is possible to contribute to downsizing of the entire image pickup apparatus incorporated.

  In particular, in the lens driving device, the plurality of lenses are configured by first, second, and third lenses, and the first lens is formed to have a smaller diameter than the second and third lenses. And the second and third lenses are disposed closer to the light entrance side, and the housing portion is located outside the lens case and on the light entrance side of the second and third lenses. Preferably it is formed. In this case, it is possible to secure a space for arranging other members, mechanisms, and the like such as an imaging device by using the difference in size between the first lens and the second and third lenses. It becomes possible.

  In the lens driving device, the lens holding unit includes a lens holder that holds a part of the electromagnetic actuator and holds the lens case, and the lens holder fixes the lens case to the electromagnetic actuator. It is preferable to accommodate from the opposite side of the surface. In this case, since the lens case for holding the lens and the lens holder to which the electromagnetic actuator is fixed are configured as separate members, the work for housing the lens in the lens case and the work for fixing the electromagnetic actuator to the lens holder The efficiency of the work of attaching the lens case itself to the lens holder can be improved.

  Furthermore, in the lens driving device, it is preferable that the magnetic body constitutes a part of the outer wall of the device housing. In this case, since the magnetic body can have the function of the outer wall of the device housing, the device housing can be downsized, and as a result, the lens driving device 1 itself can be downsized. Become.

  According to the present invention, since the accommodating portion that accommodates a part of the electromagnetic actuator constituting the moving mechanism is formed on the outer surface of the lens holder, the width of the apparatus main body is prevented from increasing according to the width of the moving mechanism. Therefore, the apparatus main body can be reduced in size.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings.
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 the present embodiment is provided with a substrate 3 on which an image sensor 2 is mounted, a base 5 on which an IR cut filter 4 is mounted, and a lens holder 6. A case 8 to which a lens case 7 is attached via a lens holder 6, a coil 9 fixed to the lens holder 6, a magnet 10 and a yoke 11 disposed above the lens holder 6, and an upper part of the case 8 And a shield case 12 that accommodates the members.

  The board | substrate 3 is provided in square shape seeing from the upper side shown in FIG. The image sensor 2 is provided in a rectangular shape when viewed from the upper side shown in FIG. 1, and is mounted on the substrate 3 such that its long side and short side are parallel to the side of the substrate 3. FIG. 1 shows a case where the image sensor 2 is mounted on the substrate 3 so that the long side 2a and the short side 2b of the image sensor 2 are parallel to the sides 3a and 3b of the substrate 3, respectively.

  The base 5 is made of, for example, an insulating resin material, and is provided in a square shape corresponding to the substrate 3. In the vicinity of the center of the base 5, a rectangular opening 5a is formed at a position corresponding to the image sensor 2, and a circular recess 5b is formed around the opening 5a. The IR cut filter 4 has a circular shape corresponding to the recess 5b and is attached to the recess 5b. Further, at the four corners of the base 5, convex portions 5c that slightly protrude upward are formed. In the vicinity of a pair of convex portions 5c disposed on the left and right diagonal lines shown in FIG. 1, a guide piece 5d is provided in contact with a guide surface 8b of the case 8 to be described later to position the case 8. . On the upper surface of the guide piece 5d, there is formed a locking piece 5e that enters an accommodating portion 12b of the shield case 12 described later. Further, at a predetermined position of the base 5, a hole portion 5 f is formed through which a connection terminal 62 f extending downward from a first leaf spring 62 described later is shown in FIG. 1.

  The case 8 is formed of, for example, an insulating resin material, and a circular opening 8a is formed at the center thereof. On the side of the case 8 corresponding to the guide piece 5d, a guide surface 8b is formed at a substantially central portion. A locking piece 8c is formed at a predetermined position on the upper surface of the guide surface 8b. The locking piece 8c enters a receiving portion 12b of the shield case 12 described later. Further, in the vicinity of the corner portion of the case 8, pins 8d are provided so as to enter holes 62d and 64d of a lens holder 6 (described later, a fixing portion 62c). Further, a housing portion 8 e for housing the outer edge portion of the lens holder 6 is formed on the outer edge portion of the case 8. Further, a notch portion 8f is formed at a predetermined position of the accommodating portion 8e to allow a connecting terminal 62f extending from a first leaf spring 62 described later to extend downward as shown in FIG.

  The lens holder 6 and the lens case 7 are attached to the case 8 having such a configuration. In this case, the lens case 7 is attached to the case 8 via the lens holder 6.

  The lens case 7 is formed of, for example, an insulating resin material, and holds a plurality of lenses 13 to 15 described later in a space formed inside. Moreover, the lens case 7 is comprised from the small diameter part 7a and the large diameter part 7b, and has a shape according to the external shape of the some lenses 13-15 hold | maintained inside. An opening 7c that functions as a light entrance is formed on the upper surface of the small diameter portion 7a. In the vicinity of the lower end of the peripheral surface of the large-diameter portion 7b, a plurality of engaging portions 7d that engage with a lens position adjusting portion 65d of the lens holder 6 described later are formed. The engaging portion 7d is formed so as to slightly protrude from the peripheral surface of the large diameter portion 7b to the side of the apparatus. The large-diameter portion 7b has a certain length in the circumferential direction and is arranged with a certain interval. The detailed shape of the lens case 7 and the configuration of the lens held in the lens case 7 will be described later.

  The lens holder 6 is configured by combining a plurality of components as will be described later. In a state where a plurality of parts are combined, the lens case 7 is held in a space formed therein so that the position of the lens case 7 can be adjusted vertically. The lens holder 6 is attached to the upper surface of the case 8 so as to be movable up and down. A coil 9 having an annular shape is fixed on the upper surface of the lens holder 6. For example, the coil 9 is bonded and fixed to the upper surface of the lens holder 6. The detailed shape of the lens holder 6 and the method for holding the lens case 7 in the lens holder 6 will be described later.

  The magnet 10 is fixed to the inner wall surface of the yoke 11 that is a magnetic body. The magnet 10 has an annular shape having a larger diameter than the coil 9. In a state of being fixed to the yoke 11, it is disposed so as to surround the periphery of the coil 9 fixed to the upper surface of the lens holder 6. The inner peripheral surface of the magnet 10 faces the outer peripheral surface of the coil 9 in a state where the magnet 10 is separated by a certain distance. Note that the length of the magnet 10 in the optical axis direction is configured to be longer than the length of the coil 9 in order to correspond to the vertical movement of the coil 9.

  The yoke 11 is fixed to the inner wall surface of the shield case 12 at a predetermined position. The yoke 11 has an annular shape that is open at the lower side shown in FIG. A space is formed inside, and the coil 9 and the magnet 10 are accommodated in this space. The magnet 10 is bonded and fixed to the inner wall surface in the space.

  The shield case 12 is made of, for example, a metal material such as stainless steel, and is configured by a box-shaped member that opens downward. On the upper surface, a circular opening 12a is formed at the center. The shield case 12 has a central portion of a pair of opposing sides slightly protruding to the side of the apparatus, and accommodates the locking piece 5e of the base 5 and the locking piece 8c of the case 8 in the vicinity of the end portion. A housing portion 12b is formed.

  Here, the configuration of the lens holder 6 will be described with reference to FIGS. FIG. 2 is an enlarged view of a main part of the lens holder 6 included in the lens driving device 1 according to the present embodiment, and FIG. 3 is an exploded perspective view thereof. 2 and 3, the outer case (see FIG. 1) that holds the components of the lens holder 6 is omitted.

  As shown in FIGS. 2 and 3, the lens holder 6 is configured by combining an upper surface portion 61, a first leaf spring 62, a spacer 63, a second leaf spring 64, and a lower surface portion 65. The An opening is formed in the central portion of each component, and as shown in FIG. 2, a space for accommodating the lens case 7 is formed inside the lens holder 6 when the components are combined. Is done. In a state of being held by the lens holder 6, the small diameter portion 7 a of the lens case 7 protrudes upward from the opening of the upper surface portion 61 as shown in FIG.

  As shown in FIG. 3, the upper surface portion 61 has a cover portion 61a that covers the vicinity of the upper surface of the large-diameter portion 7b of the lens case 7 with its inner wall surface, and an eaves formed so as to protrude from the lower end portion of the cover portion 61a toward the device Part 61b. The upper surface of the cover portion 61a functions as the upper surface of the lens holder 6 itself, and the coil 9 is bonded and fixed. For this reason, a notch 61c is formed at a predetermined position on the upper surface of the cover portion 61a to pull out one end inside the coil 9 to the outside. In addition, at a predetermined position on the outer peripheral side of the lower surface of the flange portion 61b, there is a protrusion 61d that comes into contact with a protrusion 65b of the lower surface 65 described later via a notch 62g of the first leaf spring 62 described later. Is formed. Further, at a predetermined position on the inner peripheral side of the lower surface of the flange portion 61b, a protruding portion 61e that comes into contact with a protruding portion 65c of the lower surface portion 65 described later via a notch portion 62h of the first leaf spring 62 described later. Is formed.

  The first leaf spring 62 is made of a conductive material such as phosphor bronze, for example. The first leaf spring 62 includes an annular part 62a having an opening at the center, an arm part 62b extending from a predetermined position of the annular part 62a, and a fixing part 62c provided at an end of the arm part 62b. And have. A hole 62d into which the pin 8d of the case 8 is inserted is formed near the center of the fixed portion 62c. A coil connection piece 62e that protrudes to the side of the apparatus is formed at a position corresponding to the cutout portion 61c of the upper surface portion 61 in the annular portion 62a. A connection terminal 62f to the substrate 3 is formed at a predetermined position of the fixing portion 62d disposed on the opposite side of the coil connection piece 62e. Further, on the outer peripheral side of the annular portion 62a, a notch 62g is formed at a position corresponding to the protruding portion 61d of the upper surface portion 61. On the other hand, a notch 62h is formed at a position corresponding to the protrusion 61e of the upper surface 61 on the inner peripheral side of the annular portion 62a.

  The spacer 63 has an annular portion 63a having an opening at the center. On the outer peripheral side of the annular portion 63a, a notch portion 63b is formed at a position corresponding to the protruding portion 61d of the upper surface portion 61. On the other hand, a notch 63c is formed at a position corresponding to the protrusion 61e of the upper surface 61 on the inner peripheral side of the annular portion 63a.

  Similar to the first leaf spring 62, the second leaf spring 64 is made of, for example, a conductive material such as phosphor bronze. The second leaf spring 64 includes an annular part 64a having an opening at the center, an arm part 64b extending from a predetermined position of the annular part 64a, and a fixing part 64c provided at an end of the arm part 64b. And have. A hole 64d into which the pin 8d of the case 8 is inserted is formed near the center of the fixed portion 64c. A coil connection piece 64e protruding to the side of the device is formed at a predetermined position of the annular portion 64a. A connection terminal 64f to the substrate 3 is formed at a predetermined position of the fixing portion 64d arranged on the opposite side of the coil connection piece 64e. Further, on the outer peripheral side of the annular portion 64a, a notch portion 64g is formed at a position corresponding to the protruding portion 61d of the upper surface portion 61. On the other hand, a notch 64h is formed at a position corresponding to the protrusion 61e of the upper surface portion 61 on the inner peripheral side of the annular portion 64a.

  The lower surface portion 65 has an annular portion 65a having an opening at the center. At a predetermined position on the outer peripheral side of the upper surface of the annular portion 65a, a protruding portion 65b that contacts the protruding portion 61d of the upper surface portion 61 is formed. In addition, a protrusion 65c that contacts the protrusion 61e of the upper surface 61 is formed at a predetermined position on the inner peripheral side of the upper surface of the annular portion 65a. In addition, the lens case 7 is held at a predetermined position on the inner periphery of the annular portion 65a by engaging with the engaging portion 7d, and the height of the lens case 7 is adjusted by sliding the engaging portion 7d. A lens position adjusting portion 65d that can be formed is formed.

  Here, the configuration of the lens position adjusting portion 65d formed on the lower surface portion 65 of the lens holder 6 will be described with reference to FIG. FIG. 4 is a diagram for explaining the configuration of the lens position adjusting unit 65 d formed on the lower surface portion 65 of the lens holder 6. FIG. 4 is a bottom view of the case 8 to which the lens holder 6 is attached, and shows a state before the lens case 7 is attached.

  As shown in FIG. 4, the lens position adjusting unit 65d can adjust the height of the lens case 7 according to the receiving portion 65e that receives the engaging portion 7d of the lens case 7 and the sliding amount of the received engaging portion 7d. And an adjustment groove 65f (see FIG. 3). The adjustment groove 65f is formed with a gently sloping surface so that the height of the lens case 7 can be adjusted. After putting the engaging portion 7d into the receiving portion 65e, the lens case 7 is attached to the lens holder 6 by rotating the lens case 7 so that the engaging portion 7d enters the adjusting groove portion 65f.

  The lens holder 6 includes protrusions 61d and 61e formed on the upper surface portion 61 downward and a lower surface portion 65 with the first leaf spring 62, the spacer 63, and the second leaf spring 64 interposed therebetween. For example, these components are configured to be integrated by bonding and fixing the contact surfaces with the protrusions 65b and 65c formed upward.

  The lens holder 6 having such a configuration is fixed to the pin 8d of the case 8 accommodated in the holes 62d and 64d in a state where the lens case 7 is accommodated from the lower side of the apparatus. Accordingly, the downward biasing force shown in FIG. 3 is applied to the lens holder 6 by the first and second leaf springs 62 and 64. Further, when the coil 9 is moved upward by passing an electric current, the lens holder 6 moves upward against the urging force of the first and second leaf springs 62, 64. Become.

  When assembling the lens driving device 1 having such a configuration, first, the base 5 on which the IR cut filter 4 is mounted is fixed above the substrate 3 on which the image sensor 2 is mounted. Then, the lens case 7 is mounted from the lower side, and the lens holder 6 having the coil 9 bonded and fixed from the upper side is attached to the case 8, and the case 8 is placed above the base 5. At this time, the positioning is performed by the guide surface 8 b of the case 8 and the guide piece 5 d of the base 5. Further, the yoke 11 having the magnet 10 bonded and fixed to the inner peripheral surface is fixed to the inner wall surface of the shield case 12, and the shield case 12 is covered with the case 8. At this time, the locking piece 8c of the case 8 and the locking piece 5e of the base 5 are put on the shield case 12 so as to be housed in the housing portion 12b of the shield case 12. Finally, the lens driving device 1 is assembled by bonding the shield case 12 to, for example, the case 8 and the base 5.

  In the lens driving device 1 assembled in this way, as shown in FIG. 5, the guide surface 8b of the case 8 enters a state between the guide piece 5d of the base 5 and the convex portion 5c. The locking piece 8c on 8b and the locking piece 5e on the guide piece 5d are accommodated in the accommodating portion 12b of the shield case 12. Further, the connection terminal 62 f of the lens holder 6 is connected to the substrate 3 through the notch 8 f of the case 8 and the hole 5 f (not shown in FIG. 5) of the base 5.

  Further, in the assembled lens driving device 1, as shown in FIG. 6, the opening 7c formed in the small diameter portion 7a of the lens case 7 faces the opening 12a of the shield case 12. As will be described later, when the lens holder 6 is moved up and down by passing an electric current through the coil 9, the lens case 7 is moved up and down inside the opening 12a of the shield case 12, and the lens held by this is also the same. Move up and down.

  Hereinafter, the internal configuration of the lens driving device 1 assembled in this way will be described with reference to FIG. 7 is a cross-sectional view taken along the alternate long and short dash line in FIG.

  As shown in FIG. 7, the lens case 7 is held by the lens holder 6 when the engaging portion 7d is accommodated in the lens position adjusting portion 65d. As will be described in detail later, the lens case 7 holds three lenses 13 to 15 having different sizes inside, and has a shape along the external shape thereof. Since the cover portion 61 of the lens holder 6 is placed on the upper surface of the large diameter portion 7b of the lens case 7, a certain space is formed on the side of the apparatus in the small diameter portion 7a. The lens driving device 1 according to the present embodiment uses this space as the accommodating portion 16, and accommodates the coil 9 in the accommodating portion 16 and arranges the magnet 10 and the yoke 11 on the outside thereof.

  The coil 9, the magnet 10, and the yoke 11 constitute a moving mechanism that moves the lens holder 6 and the lens case 7. In the present embodiment, the moving mechanism is composed of an electromagnetic actuator, specifically, a so-called voice coil motor. In particular, the present embodiment shows a case where a moving coil type voice coil motor that moves the coil 9 along the magnet 10 by energizing the coil 9 is applied.

  Here, the configuration of the lens case 7 and the configurations of the plurality of lenses 13 to 15 held by the lens case 7 will be described with reference to FIG. FIG. 8 is a schematic diagram for explaining the configuration of the lens case 7 and the lenses 13 to 15 held by the lens case 7 according to the present embodiment.

  As shown in FIG. 8, the lens case 7 includes three first lenses 13, second lenses 14, and third lenses 15, which are formed of a resin material and have different shapes, along the optical axis direction. Store. Here, the first lens 13 has a smaller diameter than the second lens 14 and is disposed at a predetermined position on the second lens 14. The second lens 14 is formed with a smaller diameter than the third lens 15 and is disposed at a predetermined position on the third lens 15. The lens case 7 is provided in a shape that follows the external shape of the first lens 13, the second lens 14, and the third lens 15 that are arranged in this manner.

  In the lens driving device 1 according to the present embodiment, the first lens 13 has a lens portion 13a including a convex lens. A bulging portion 13 b that bulges upward is formed at the center of the first lens 13, and an annular positioning portion 13 c that protrudes downward is formed at the outer peripheral edge thereof. The positioning portion 13c is formed as a part of the lens portion 13a and is formed with the same accuracy as the lens portion 13a.

  The second lens 14 has a lens portion 14a including a concave lens. A circular protruding portion 14b that protrudes slightly upward is formed at the center of the lens portion 14a, and an arcuate positioning portion 14c that protrudes downward is formed at the outer peripheral edge thereof. The central portion of the protruding portion 14b is slightly recessed downward. Moreover, the peripheral part of the upper surface of the protrusion part 14b functions as the positioning part 14d engaged with the positioning part 13c. In addition, the positioning part 14c and the positioning part 14d are formed as a part of the lens part 14a similarly to the positioning part 13c.

  Further, the third lens 15 has a lens portion 15a including an aspheric lens. An arcuate positioning portion 15b protruding upward is formed on the outer peripheral edge of the lens portion 15a. The positioning portion 15b is formed as a part of the lens portion 15a, like the positioning portion 13c and the positioning portion 14c.

  When the first lens 13, the second lens 14, and the third lens 15 are housed in the lens case 7, the positioning portion 13 c of the first lens 13 is projected from the second lens 14 as shown in FIG. 8. The first lens 13 is disposed above the second lens 14 so as to coincide with the outer peripheral surface of the positioning portion 14d of the portion 14c. Then, the second lens 14 is disposed above the third lens 15 so that the positioning portion 14 c of the second lens 14 is aligned with the outer peripheral surface of the positioning portion 15 b of the third lens 15. Then, these lenses are housed in the lens case 7 so that the peripheral surface portion of the third lens 15 is in contact with the inner peripheral surface of the lens case 7.

  Next, in the lens driving device 1 according to the present embodiment, control when the lenses 13 to 15 are moved up and down will be described with reference to FIG.

  In the lens driving device 1 according to the present embodiment, when driving the lenses 13 to 15, for example, the coil 9 according to a driving instruction from a control unit of a mobile phone or digital camera equipped with the lens driving device 1. A current is passed through. At this time, in the lens driving device 1, the first plate spring 62 and the second plate spring 64 are used as the energizing means. Specifically, current is sent from the substrate 3 to the coil 9 through the connection terminal 62f, the arm portion 62b, the annular portion 62a, and the coil connection piece 62e formed on the fixing portion 62c of the first leaf spring 62. . The current flowing through the coil 9 is sent to the substrate 3 via the connection terminals 64f formed on the coil connection piece 64e, the annular portion 64a, the arm portion 64b, and the fixing portion 64c of the second leaf spring 64.

  When current flows through the coil 9 in this way, the current flowing through the coil 9 acts on the magnetic field generated from the magnet 10 to generate thrust for moving the coil 9 in the vertical direction shown in FIG. In the lens driving device 1 according to the present embodiment, this thrust is controlled by controlling the amount of current flowing through the coil 9, and the coil 9 is moved up and down to perform positioning. As a result, the lens holder 6 to which the coil 9 is fixed can be positioned, and the lenses 13 to 15 in the lens case 7 attached to the lens holder 6 can be positioned.

  As shown in FIG. 7, the yoke 11 has a U-shaped cross section that is open downward. The lower end portion 11a of the circumferential surface disposed on the inner side is set shorter than the lower end portion 11b of the circumferential surface disposed on the outer side. The lower end portion 11a is disposed in the vicinity of the small diameter portion 7a of the lens case 7, and is disposed on the upper surface side of the large diameter portion 7b. The lower end portion 11a functions as a regulating member for the lens holder 6 that moves up and down according to the amount of current. That is, the lower end portion 11a abuts on the upper surface of the large diameter portion 7b, thereby restricting the lens holder 6 from moving upward beyond a certain position. As a result, the coil 9 can be prevented from colliding with the yoke 11, and the coil 9 and the yoke 11 are prevented from being damaged.

  Thus, according to the lens driving device 1 according to the present embodiment, the housing portion 16 that houses a part of the electromagnetic actuator (voice coil motor) on the outer surface of the lens holder 6 and the lens case 7 as the lens holding means. Since it is formed, the width of the apparatus main body is prevented from increasing in accordance with the width of the electromagnetic actuator, so that the apparatus main body can be reduced in size. Moreover, since a part of electromagnetic actuator is accommodated in the accommodating part 16, it becomes possible to prevent the situation which the center position of an apparatus main body and the center positions of the lenses 13-15 hold | maintained at an apparatus shift | deviate. .

  In particular, in the lens driving device 1 according to the present embodiment, the electromagnetic actuator (voice coil motor) includes an annular magnet 10 and a coil 9 wound in an annular shape, A shape corresponding to the shape of the coil 9 is provided. Thus, since the accommodating part 16 is provided in the shape according to the shape of the coil 9 which has an annular shape, and the coil 9 is accommodated in this accommodating part 16, an apparatus main body is utilized effectively using the limited space. Can be miniaturized.

  In the lens driving device 1 according to the present embodiment, the lens holder 6 and the lens case 7 are attached to the housing of the lens driving device 1 by first and second leaf springs 62 and 64. Thereby, since the urging force by the first and second leaf springs 62 and 64 always acts on the lens holder 6 and the lens case 7, even when these are moved in the optical axis direction according to the energization to the coil 9. The lens holder 6 and the lens case 7 can be stabilized.

  In particular, in the lens driving device 1 according to the present embodiment, the coil 9 is energized through the first and second leaf springs 62 and 64. As a result, wiring for energizing the coil 9 is not required, and the configuration in the lens driving device 1 can be simplified.

  Further, in the lens driving device 1 according to the present embodiment, the lens case 7 is provided in a shape corresponding to the outer shape of the plurality of lenses 13 to 15 housed therein. Accordingly, it is possible to prevent the lens case 7 and the lens holder 6 from being unnecessarily large, and therefore, in an imaging apparatus or the like incorporating the lens holder 6, other members, moving mechanisms, and the like are arranged. Space can be secured.

  In particular, in the lens driving device 1 according to the present embodiment, the first lens 13 is formed to have a smaller diameter than the second lens 14 and the third lens 15 and is also smaller than the second lens 14 and the third lens 15. Arranged on the light entrance side, the accommodating portion 16 is formed outside the lens case 7 at a position on the light entrance side of the second lens 14 and the third lens 15. Accordingly, it is possible to secure a space for arranging other members, mechanisms, and the like such as an imaging device by using the difference in size between the first lens 13, the second lens 14, and the third lens 15. It becomes possible.

  Further, in the lens driving device 1 according to the present embodiment, the coil 9 is bonded and fixed, and the lens holder 6 that holds the lens case 7 is provided. The lens holder 6 is fixed to the lens case 7 by the coil 9. It accommodates from the opposite side (namely, the lower side shown in FIG. 1) of the surface to be formed. Thus, since the lens case 7 that holds the lenses 13 to 15 and the lens holder 6 to which the coil 9 is bonded and fixed are configured as separate members, the operation of housing the lenses 13 to 15 in the lens case 7, It is possible to improve the efficiency of the work of bonding and fixing the coil 9 to the lens holder 6 and the work of attaching the lens case 7 itself to the lens holder 6.

  In addition, this invention is not limited to the said embodiment, It can change and implement variously. In the above-described embodiment, the size, shape, and the like illustrated in the accompanying drawings are not limited to this, and can be appropriately changed within a range in which the effect of the present invention is exhibited. In addition, various modifications can be made without departing from the scope of the object of the present invention.

  For example, in the above embodiment, a case where a so-called moving coil type voice coil motor that moves the coil 9 relative to the magnet 10 is applied as the moving mechanism of the lens holder 6 is shown. However, the moving mechanism of the lens holder 6 is not limited to this. For example, a so-called moving magnet type voice coil motor that moves the magnet 10 relative to the coil 9 can be applied. Even when such a moving magnet type voice coil motor is applied, it is possible to obtain the same effect as the above-described embodiment.

  Moreover, in the said embodiment, the case where the yoke 11 is fixed to the inner wall face of the shield case 12 is shown. However, the configuration of the shield case 12 is not limited to this, and can be changed as appropriate. For example, as shown in FIG. 9, a part of the outer peripheral surface of the yoke 11 may be exposed from the shield case 12 to constitute a part of the shield case 12. In this case, since the function of the shield case 12 can be provided on the outer peripheral surface of the yoke 11, the shield case 12 can be reduced in size, and as a result, the lens driving device 1 itself can be reduced in size. It becomes.

It is a disassembled perspective view of the lens drive device which concerns on one embodiment of this invention. It is a principal part enlarged view of the lens holder which the lens drive device which concerns on the said embodiment has. It is a disassembled perspective view of the lens holder which the lens drive device concerning the above-mentioned embodiment has. It is a figure for demonstrating the structure of the lens position adjustment part formed in the lens holder which the lens drive device which concerns on the said embodiment has. It is an external appearance perspective view at the time of assembling the lens drive device which concerns on the said embodiment. It is a top view at the time of assembling the lens drive device which concerns on the said embodiment. It is sectional drawing in the dashed-dotted line shown in FIG. It is a schematic diagram for demonstrating the structure of the lens case which this lens drive device which concerns on the said embodiment has, and this. It is an external appearance perspective view of the lens drive device which concerns on the modification of the said embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Lens drive device 2 Image sensor 3 Board | substrate 4 IR cut filter 5 Base 6 Lens holder 61 Upper surface part 62 1st leaf | plate spring 63 Spacer 64 2nd leaf | plate spring 65 Lower surface part 7 Lens case 8 Case 9 Coil 10 Magnet 11 Yoke 12 Shield case 13 First lens 14 Second lens 15 Third lens 16 Housing

Claims (11)

  A lens driving device comprising: a lens holding unit that holds a lens; and a moving mechanism that moves the lens holding unit along an optical axis direction, the moving mechanism including a magnet, a coil, and a magnetic body, A lens driving device comprising an electromagnetic actuator that operates by energizing a coil, and a housing portion that houses a part of the electromagnetic actuator is formed on an outer surface of the lens holding means.   The electromagnetic actuator includes an annular magnet and a coil wound in an annular shape, and the accommodating portion has a shape corresponding to the shape of the magnet or the coil. Lens drive device.   While fixing the magnet to the lens holding means, the coil is fixed to the outside of the lens holding means so as to be opposed to the magnet, and the magnet is moved in the optical axis direction by energizing the coil. The lens driving device according to claim 1 or 2.   The coil is fixed to the lens holding means, while the magnet is fixed to the outside of the lens holding means so as to face the coil, and the coil is moved in the optical axis direction by energizing the coil. The lens driving device according to claim 1 or 2.   The lens driving device according to any one of claims 1 to 4, wherein the lens holding means is attached to the device housing by a leaf spring.   6. The lens driving device according to claim 5, wherein the lens holding means is attached to the apparatus housing by a plurality of the plate springs.   The lens driving device according to claim 5, wherein the coil is energized through the leaf spring.   The lens holding means includes a lens case for storing a plurality of lenses having different shapes along the optical axis direction, and the lens case has a shape corresponding to the outer shape of the plurality of lenses stored in the lens case. The lens driving device according to claim 1, comprising: a lens driving device according to claim 1.   The plurality of lenses includes first, second, and third lenses. The first lens is formed with a smaller diameter than the second and third lenses, and the second and second lenses are formed. 3 is arranged on the light entrance side of the third lens, and the housing portion is formed outside the lens case and at a position on the light entrance side of the second and third lenses. The lens driving device according to claim 8.   The lens holding means includes a lens holder that holds the lens case while a part of the electromagnetic actuator is fixed, and the lens holder accommodates the lens case from the opposite side of the surface to which the electromagnetic actuator is fixed. The lens driving device according to claim 8 or 9, wherein   The lens driving device according to claim 1, wherein the magnetic body constitutes a part of an outer wall of the device housing.

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