JP2008175946A - Optical module, lens driving apparatus and mobile phone with camera - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical module which can easily be manufactured and assembled and is excellent in quality, and to provide a lens driving apparatus and a mobile phone with camera. <P>SOLUTION: This optical module 10 is provided with: a cylindrical barrel 2 in which a lens 4 is fixed to the inner periphery thereof; and a cylindrical lens support body 7 for attaching the barrel 2 to the inner periphery thereof. The barrel 2 has large-diameter parts 2a each formed on the outer peripheral surface thereof, whose diameter becomes gradually larger in the peripheral direction. The lens support body 7 has small diameter parts 7a each formed on the inner peripheral surface thereof, whose diameter becomes gradually smaller in the peripheral direction. In the case of attaching the barrel 2 to the lens support body 7, by setting the barrel 2 in the inner periphery of the lens support body 7 and rotating the barrel 2, the large-diameter parts 2a formed on the outer peripheral surface of the barrel 2 are brought in press contact with the small-diameter parts 7a formed on the inner peripheral surface of the lens support body 7, then, the barrel 2 is fixed. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an optical module for a small camera, a lens driving device including the optical module, and a mobile phone with a camera.

  Patent Document 1 discloses that a lens barrel is attached to the inner periphery of a cylindrical lens support with a cylindrical barrel having a lens fixed to the inner periphery. In this technique, a thread groove (male thread) is formed on the outer periphery of the barrel, a thread groove (female thread) that meshes with the thread groove of the barrel is also formed on the inner periphery of the lens support, and the barrel is threaded. It is fixed to the lens support.

JP 2006-284651 A

  However, in the technique of Patent Document 1, since the barrel is fixed to the lens support by screw engagement, there is a problem that the barrel needs to be rotated once (360 degrees) or more, and the assembly becomes complicated.

  Further, when screwing together, there is a risk that the threaded portion is rubbed and wrinkles (dust) are generated. In particular, in an optical module, a slight amount of dust may hinder the quality.

  Furthermore, since it is necessary to form a screw on each of the outer peripheral surface of the barrel and the inner peripheral surface of the lens support, there is a problem that it takes time and effort to manufacture.

  Accordingly, an object of the present invention is to provide an optical module, a lens driving device, and a camera-equipped mobile phone that are easy to manufacture and assemble and have good quality.

  The invention according to claim 1 is an optical module comprising a cylindrical barrel having a lens fixed to the inner periphery and a cylindrical lens support for attaching the barrel to the inner periphery. The barrel gradually increases in the circumferential direction on the outer peripheral surface. The lens support has a large-diameter portion with a larger diameter, the lens support has a small-diameter portion with a gradually decreasing diameter in the circumferential direction on the inner peripheral surface, and the barrel is attached to the inner periphery of the lens support when the barrel is attached to the lens support. The optical module is characterized in that the large-diameter portion on the outer peripheral surface of the barrel and the small-diameter portion on the inner peripheral surface of the lens support are pressed and fixed by rotating the barrel with the arrangement.

  The invention according to claim 2 is the invention according to claim 1, wherein a plurality of stepped portions having different diameters in the circumferential direction are formed on the outer periphery of the barrel at intervals in the circumferential direction. The portion gradually increases in diameter in the circumferential direction from the stepped portion to the adjacent stepped portion, and on the inner peripheral surface of the lens support, there is a stepped portion having a different diameter in the circumferential direction at a position corresponding to the stepped portion of the barrel. A plurality of small diameter portions are formed such that the diameter gradually decreases in the circumferential direction from the step portion to the next step portion.

  According to a third aspect of the present invention, in the first aspect of the present invention, the outer peripheral surface of the barrel has an elliptical cross section perpendicular to the optical axis of the lens, and the inner peripheral surface of the lens support is in the optical axis of the lens. The orthogonal cross section is an ellipse.

  The invention described in claim 4 includes the optical module according to claim 1, an annular yoke, an annular coil, a magnet, and a spring, and the lens support is disposed on the inner peripheral side of the yoke. A coil is fixed to the outer periphery, a magnet is fixed to the yoke, and a spring is provided between the yoke and the lens support to support the lens support so as to be movable in the optical axis direction with respect to the yoke. The lens driving device is characterized in that the lens support is moved back and forth along the optical axis direction of the lens by electromagnetic force generated by energizing the lens.

  According to a fifth aspect of the present invention, there is provided a camera-equipped mobile phone including a camera having the lens driving device according to the fourth aspect and an image sensor provided on an optical axis.

  According to the first aspect of the present invention, since the thread groove is not formed on the outer peripheral surface of the barrel and the inner peripheral surface of the lens support body, the step of forming the thread groove can be omitted, and the manufacturing is easy.

  Since the barrel is rotated with respect to the lens support, the large-diameter portion of the outer peripheral surface of the barrel and the small-diameter portion of the peripheral surface of the lens support are pressed and fixed. Degree) and can be easily assembled. In addition, since the screw engagement is not performed, the occurrence of wrinkles can be prevented without friction due to the screw engagement.

  According to the second aspect of the present invention, the effect of the first aspect is achieved, and the barrel is inserted into the inner periphery of the lens support by aligning the stepped portion of the barrel with the stepped portion of the lens support. Therefore, positioning when inserting the barrel into the lens support can be easily performed using the stepped portion as a mark.

  Since the large-diameter portion and the small-diameter portion are provided at a plurality of positions in the circumferential direction, the barrel and the lens support can be pressed and fixed at a smaller rotation angle.

  According to the invention described in claim 3, the effect described in claim 1 can be obtained, the outer periphery of the barrel has an elliptical major axis as a large diameter portion, and the lens support has an elliptical minor axis as a small diameter. Since the major axis (or short axis) of the ellipse of the barrel matches the major axis (or short axis) of the ellipse of the lens support, the barrel is inserted into the inner periphery of the lens support and rotated. Therefore, positioning when inserting the barrel into the lens support can be facilitated by making the major axis or minor axis of the ellipse coincide.

  Since the large-diameter portion and the small-diameter portion are in a perpendicular position, the barrel and the lens support can be pressed and fixed at a rotation angle of 90 degrees or less.

  According to the invention described in claim 4, it is possible to provide a lens driving device capable of obtaining the function and effect described in claim 1.

  According to the invention described in claim 5, it is possible to provide a camera-equipped mobile phone capable of obtaining the function and effect described in claim 4.

  Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a cross-sectional view of a lens driving device in which a barrel and a lens support are extracted, FIG. 2 is a perspective view showing a state before the barrel is mounted in the lens driving device, and FIG. 3 is a perspective view of the lens driving device. FIG. 4 is an exploded perspective view, and FIG. 4 is a longitudinal sectional view of a lens driving device mounted on a substrate.

  A lens driving device 1 according to the present embodiment is a lens driving device for an autofocus camera incorporated in a mobile phone. As shown in FIGS. 3 and 4, the lens driving device 1 includes a barrel 2 having a lens 4 fixed to the inner periphery, a lens support 7 for attaching the barrel 2 to the inner periphery, an annular yoke 3, and a front spring. 9, a rear spring 11, a base 5 (housing) disposed on the rear side of the yoke 3, and a frame (housing) 6 disposed on the front side of the yoke, and the lens 4 is fixed. The barrel 2 and the lens support 7 constitute an optical module 10. An insulator (spacer) 17 is disposed between the yoke 3 and the rear spring 11. This lens driving device 1 is very small with about 10 mm in length and width and about 3.5 mm in height.

  The barrel 2 has a cylindrical main body, and no screw is formed on the outer peripheral surface. As shown in FIG. 1, in the circumferential direction of the outer peripheral surface of the barrel 2, three large-diameter portions 2a with gradually increasing diameters are formed at equal intervals in the circumferential direction. On the outer peripheral surface of the barrel 2, there is formed a step portion 2b having a step having a different diameter in the circumferential direction, and the large diameter portion 2a gradually increases in diameter from the step portion 2b to the adjacent step portion 2b. ing. That is, the outer peripheral surface of the barrel is formed with a large-diameter portion 2a and a step portion 2b that are gradually increased in diameter in the circumferential direction at three locations in the circumferential direction. The barrel 2 is made of resin and is manufactured by molding.

  Note that, on the front side of the barrel 2 (see FIG. 3), a square-shaped portion 2 c in plan view is a grip portion that is gripped by a jig when the barrel 2 is assembled to the lens support 7.

  The lens support 7 has a cylindrical shape, and no screw is formed on the inner peripheral surface thereof. In the circumferential direction of the inner peripheral surface of the lens support 7, three small diameter portions 7 a having a gradually reduced diameter are formed at equal intervals in the circumferential direction. On the inner peripheral surface of the lens support, three stepped portions 7b are formed at positions corresponding to the stepped portion 2b of the barrel 2, and the small diameter portion 7a extends from the stepped portion 7b to the adjacent stepped portion 7b. The diameter is gradually reduced. That is, the inner peripheral surface of the lens support 7 is formed with a small-diameter portion 7b and a step portion 7b that are gradually reduced in diameter in the circumferential direction at three locations in the circumferential direction. The lens support 7 is made of resin and is manufactured by molding.

  The lens support 7 is disposed on the inner peripheral side of the yoke 3, and is provided so as to be movable in the optical axis direction (front-rear direction) on the inner peripheral side of the yoke 3. The coil 15 is fixed.

  As shown in FIG. 3, the yoke 3 has an outer periphery that is a quadrangle in plan view and an inner periphery that is circular in plan view, as seen from the front side, and a rectangular outer peripheral wall 3a, a cylindrical inner peripheral wall 3b, The outer peripheral wall 3a and the inner peripheral wall 3b are connected to each other with a connecting wall 3c that is connected at an interval, and the outer peripheral wall 3a, the inner peripheral wall 3b, and the connecting wall 3c have a U-shaped cross section. The outer peripheral wall 3a and the inner peripheral wall 3b have substantially the same dimensions in the moving direction (front-rear direction) of the lens support 7. On the inner peripheral wall 3b, a cut portion 12 is formed from the rear end toward the front. The cut portions 12 are arranged at equal intervals in the circumferential direction. In the present embodiment, the cut portions 12 are provided at positions corresponding to the space between the adjacent corner portions 14 (plane portions) in the rectangular outer peripheral wall 3a in plan view. It is.

  At each corner 14 of the yoke 3, a magnet 13 is fixed to the inner peripheral surface of the outer peripheral wall 3a. The magnet 13 is provided only in the corner portion 14 and is not located at a position corresponding to the cut portion 12 formed in the inner peripheral wall 3b.

  The coil 15 is disposed between the outer peripheral wall 3 a and the inner peripheral wall 3 b of the yoke 3, but the magnet 13 is located between the magnet 13 and the inner peripheral wall 3 b at the corner portion 14 where the magnet 13 is located, Is designed to move forward and backward.

  The coil fixing portions 22 are arranged at intervals in the circumferential direction of the outer peripheral surface of the lens support 7, and are located in the cutout portion 12 provided on the inner peripheral wall 3 b of the yoke 3.

  The front spring 9 is an annular leaf spring, and is provided with an inner peripheral side portion 9a and an outer peripheral side portion 9b. The inner peripheral side portion 9a is attached to the lens support 7, and the outer peripheral side portion 9b is connected to the yoke 3. It is sandwiched and fixed between the frame 6. The inner peripheral side portion 9a and the outer peripheral side portion 9b are connected by an elastically deformable arm portion 9c.

  Although the rear spring 11 is an annular leaf spring as a whole, in this embodiment, the rear spring 11 is composed of one side portion 30 and the other side portion 32 which are divided into left and right. The outer peripheral side portions 11 b and 11 b of the rear spring 11 are sandwiched between the base 5 and the yoke 3 via an insulator (spacer) 17, and the insulator 17 is formed between the rear spring 11 and the yoke 3. The electrical insulation between them is intended. The inner peripheral side portions 11 a and 11 a are attached to the rear end of the lens support 7. Each inner peripheral side portion 11a and outer peripheral side portion 11b of the rear spring 11 are connected by an elastically deformable arm portion 11c.

  In the present embodiment, a terminal 18 is formed on one side 30 constituting the rear spring 11, a terminal 19 is formed on the other side 32, and the terminals 18 and 19 are connected to power supply terminals. It has come to be. The one side portion 30 and the other side portion 32 are electrically connected to the coil 15 by soldering or the like, respectively, so that the coil 15 is energized from the rear spring 11.

  These front springs 9 and rear springs 11 are flat in a natural state before assembly (a state before the frame 6 is assembled) (see FIG. 3), but at least the front spring 9 is in FIG. 4 after the assembly. As shown, the inner peripheral side portion 9a is attached in a state of being elastically deformed so as to be positioned in front of the outer peripheral side portion 9b. As a result, the inner peripheral side portion 9a constantly urges the lens support 7 with the urging force directed toward the base 5 by the restoring force (urging force) of the spring.

  The frame 6 is disposed on the front side of the lens support 7, holds the outer peripheral side portion 9 b of the front spring 9 between the yoke 3, and fits and fixes to the base 5 to fix the base 5 and the frame 6. The casing is formed with.

  As shown in FIG. 4, the lens driving device 1 is fixed to a substrate 31 on which an image sensor 29 is mounted, and forms an image of a subject on the image sensor 29.

  Next, operations and effects of the lens driving device 1 according to the present invention will be described. As shown in FIGS. 1 and 2, the optical module 10 is assembled by aligning the stepped portion 2b of the barrel 2 with the stepped portion 7b of the lens support 7, and inserting the barrel 2 into the inner periphery of the lens support 7. Then, the barrel 2 is rotated by a jig (not shown) as indicated by an arrow, and the large-diameter portion 2a of the barrel 2 is press-fixed to the small-diameter portion 7a of the lens support 7. After the barrel 2 and the lens support 7 are pressed and fixed, an adhesive is poured into the gap between the barrel 2 and the lens support 7 and hardened.

  According to the present embodiment, the positioning when the barrel 2 is inserted into the inner periphery of the lens support 7 may be inserted with the stepped portion 2b of the barrel 2 and the stepped portion 7b of the lens support 7 aligned. Therefore, the stepped portions 2a and 7b can be easily used as marks.

  Since the large-diameter portion 2a of the barrel 2 and the small-diameter portion 7b of the lens support body 7 are provided at three positions in the circumferential direction, the barrel 2 and the lens support body 7 can be pressed and fixed by rotation of at least 120 degrees or less. In addition, since the barrel 2 and the lens support 7 are pressed and fixed at three locations in the circumferential direction, the barrel 2 and the lens support 7 can be stably held by the three-point support in the space of the lens support 7.

  Since no thread groove is formed on the outer peripheral surface of the barrel 2 and the inner peripheral surface of the lens support 7, the process for forming the thread groove can be omitted, and manufacturing is easy.

  Since the barrel 2 and the lens support 7 do not engage with each other, there is no rubbing due to the engagement between the screws and the generation of wrinkles can be prevented.

  In the lens driving device 1 according to the present embodiment, when the lens support 7 is moved, when the coil 15 is energized from the terminals 18 and 19, the lens support 7 is moved to the front spring 9 and the rear by electromagnetic force acting on the coil 15. It moves against the urging force of the side spring 11 and stops at a position where the forces with the springs 9 and 11 are balanced.

  The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the present invention.

  For example, as shown in FIG. 5, the outer peripheral surface of the barrel 2 has an elliptical cross section orthogonal to the optical axis of the lens, and the inner peripheral surface of the lens support 7 has an elliptical cross section orthogonal to the optical axis of the lens. The barrel 2 is inserted into the inner periphery of the lens support 7 by aligning the major axes of the inner periphery of the lens support 7 and the ellipse of the outer periphery of the barrel. The large diameter portion 2a of the barrel 2 may be pressed and fixed to the small diameter portion 7a of the lens support 7 by rotating the barrel 2 with respect to the lens support 7. In this case, the barrel 2 and the lens support 7 are fixed by pressure contact at two locations. After the barrel 2 and the lens support 7 are pressed and fixed, an adhesive is poured into the gap between the lens support 7 and the barrel 2 and hardened.

  Fixing the barrel 2 and the lens support 7 with an adhesive is performed by applying an adhesive to one or both of the barrel 2 and the lens support 7 before assembling them, and fixing them by thermosetting after assembling. It may be what you do.

It is a cross-sectional view of a lens driving device that shows a barrel and a lens support. It is a perspective view which shows the state before attachment of a barrel in a lens drive device. It is a disassembled perspective view of a lens drive device. It is a longitudinal cross-sectional view of the lens drive device mounted in the board | substrate. It is a figure which shows other embodiment, and is a cross-sectional view of the lens drive device which extracts and shows a barrel and a lens support body.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Lens drive device 2 Barrel 2a Large diameter part 2b Step part 3 Yoke 4 Lens 7 Lens support body 7a Small diameter part 7b Step 9 Front spring 11 Rear spring 13 Magnet 15 Coil

Claims (5)

In an optical module comprising a cylindrical barrel with a lens fixed on the inner periphery and a cylindrical lens support for mounting the barrel on the inner periphery,
The barrel has a large-diameter portion whose diameter is gradually increased in the circumferential direction on the outer peripheral surface, and the lens support has a small-diameter portion whose diameter is gradually decreased in the circumferential direction on the inner peripheral surface, and the barrel is attached to the lens support. The barrel is arranged on the inner periphery of the lens support and the barrel is rotated so that the large diameter portion of the outer peripheral surface of the barrel and the small diameter portion of the inner peripheral surface of the lens support are fixed in pressure contact with each other. Optical module.   On the outer periphery of the barrel, a plurality of stepped portions having different diameters in the circumferential direction are formed at intervals in the circumferential direction, and the large-diameter portion gradually increases in diameter in the circumferential direction from the stepped portion to the adjacent stepped portion. A plurality of stepped portions having different diameters in the circumferential direction are formed at positions corresponding to the stepped portion of the barrel on the inner peripheral surface of the lens support, and the small-diameter portion extends from the stepped portion to the next stepped portion. The optical module according to claim 1, wherein the diameter is gradually reduced in the direction.   2. The outer peripheral surface of the barrel has an elliptical cross section perpendicular to the optical axis of the lens, and the inner peripheral surface of the lens support has an elliptical cross section orthogonal to the optical axis of the lens. An optical module according to 1.   The optical module according to claim 1, an annular yoke, an annular coil, a magnet, and a spring, the lens support is disposed on the inner peripheral side of the yoke, and the coil is fixed to the outer periphery. It is fixed to the yoke, and a spring is provided between the yoke and the lens support so as to support the lens support so as to be movable in the direction of the optical axis with respect to the yoke. A lens driving device, wherein the support is moved back and forth along the optical axis direction of the lens.   A camera-equipped mobile phone, comprising a camera having the lens driving device according to claim 4 and an image sensor provided on an optical axis.

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