JP2007093707A - Camera module - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a camera module which is not damaged even when an impact by falling and vibration in conveyance. <P>SOLUTION: A buffering mechanism is provided inside the camera module 20 itself. The camera module 20 separates an optical system provided in a first casing 29 and a drive mechanism provided in a second casing 39 and elastically connects the drive mechanism to a specific optical element of an optical system by plate springs 36, 37 with rack. Then, an optical base 31 of the optical system is supported to the first casing 29 by the buffering mechanism. Thus, since the drive mechanism and the optical system are separated, acceleration such as impact force regarding the optical system is comparatively small, large falling impulsive resistance property is obtained, the buffering mechanism is simplified to attain miniaturization, thickness reduction and cost reduction. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a camera module that drives a lens, and more particularly, to a camera module that is not easily damaged even when subjected to an impact or vibration.

  In recent years, mobile information devices such as mobile phones and information terminals equipped with camera modules are increasing. Further, such portable information devices are required to be further reduced in size and thickness. In addition, camera modules installed in portable information devices have been improved in functionality from fixed focus types called pan-focus to movable focus types that have autofocus and zoom functions. Due to the demand for reduction in size and thickness, the camera module itself is also required to be reduced in size and thickness. On the other hand, such a camera module is required to have a drop-proof performance that does not break even if the user accidentally drops the portable information device. For example, the drop impact acceleration that occurs when a portable information device is dropped from a height of 1.7 m onto a concrete block is generally said to be about 6000 G, but in particular, the camera module is highly functional. In addition, the structure is complicated, and the strength of the parts used tends to be insufficient, so that the drop impact resistance of the camera module itself is low.

  In order to solve this problem, in the mobile phone described in Japanese Patent Application Laid-Open No. 2004-61530 (Patent Document 1), a cushioning material is interposed between the front-side housing and the back-side housing of the mobile phone itself. The structure that holds the entire camera module is adopted. The structure will be described in detail with reference to FIG. 8. The mobile phone 310 includes a main body 320 made of a metal material or a resin material, an image capturing unit 330, and a mounting substrate 340. The main body 320 includes a front housing (first housing) 321 and a back housing (second housing) 322 disposed opposite to the front housing 321. The image capturing unit 330 includes a camera module 300 and a shock absorber 332. The shock absorber 332 includes buffer materials 333 and 334 such as a resin fixed to the front housing 321 and the back housing 322, respectively. The cushioning member 333 has a side fixed portion 333 a that contacts the side surface of the camera module 300, and an upper end surface 333 b that is bonded to the inner wall surface 321 a of the front housing 321. On the other hand, the cushioning member 334 has a fixing portion 334 a provided on a side surface thereof in contact with the module substrate 300 b of the camera module 300, and a lower end surface 334 b fixed to the inner wall surface 322 a of the back side housing 322. . The mounting board 340 includes a wiring board 341 made of a glass epoxy material, an electronic component 342 mounted on the wiring board 341, and a signal line 343 used for connection to the module board 300b described above. Yes.

  In the mobile phone device 310 configured in this manner, the camera module 300 is supported by the front housing 321 and the back housing 322 via the cushioning materials 332 and 334, so that when the camera module 300 falls on the floor or the like, Even when an impact or vibration is applied during transportation of the vehicle or the like, the impact or the like is alleviated, so that the camera module 300 can be prevented from being damaged.

  By the way, in portable information devices such as mobile phones, apart from the above-described miniaturization and thinning, there is a strong demand for higher functions such as a position search function and a music distribution function. Therefore, it has become difficult to attach a camera module, which is a relatively large component, to the main body via a cushioning material. The demand for high functionality and the demand for miniaturization and thinning combine with each other, and there is no space in the main body for the buffer material itself.

  However, a highly functional camera module requires a shock-absorbing material with higher shock absorption capacity because of its increased drop impact force due to its increased weight, which in turn requires additional space and associated cost increases. There is a problem of becoming.

Further, in the mobile phone of Patent Document 1, buffer materials 333 and 334 are provided between the camera module 300 and the front-side casing 321 and between the camera module 300 and the rear-side casing 322, respectively. Therefore, when the structure of the mobile phone itself is changed, the structure of the cushioning materials 333 and 334 itself must be changed, resulting in an increase in manufacturing cost.
JP 2004-61530 A

  Therefore, an object of the present invention is not to necessarily provide a shock absorber between the camera module and the main body of the portable information device, the camera module itself has a drop impact resistance, and can be reduced in size and thickness. To provide a module.

In order to solve the above problems, the camera module of the present invention is:
A first housing;
An optical system provided in the first casing and including an optical base and a plurality of optical elements mounted on the optical base;
A buffer mechanism for supporting the optical base on the first housing;
A second housing attached to the first housing so as to cover at least a part of the optical system;
A drive mechanism provided on the second housing and for moving a specific optical element in the optical system in the optical axis direction;
A power transmission unit that elastically connects the specific optical element and the drive mechanism and transmits the power of the drive mechanism to the specific optical element is provided.

  According to the above configuration, since the buffer mechanism is provided inside the camera module itself, there is no need to provide a buffer mechanism between the camera module and the main body of the portable information device as in the prior art. This camera module can be used as is when the camera is changed. Therefore, this camera module can be directly applied to portable information devices having various structures and has high versatility. As a result, the manufacturing cost of the portable information device can be reduced.

  The camera module separates the optical system provided in the first casing and the drive mechanism provided in the second casing, and elastically connects the drive mechanism and a specific optical element of the optical system. It is connected to the power transmission part. The optical base of the optical system is supported on the first housing by a buffer mechanism. In this way, the drive mechanism that is relatively strong against shock and vibration and has a relatively large mass is separated from the optical system that is relatively weak against shock and vibration. The acceleration of force and the like is relatively small, a large drop impact resistance can be obtained, and the shock absorbing mechanism can be simplified to achieve a reduction in size, thickness and cost. Since the drive mechanism and the specific optical element are elastically connected by a power transmission unit, even if a large drop impact force is applied to the drive mechanism, the impact force applied to the optical system is reduced. is there.

  In one embodiment, the buffer mechanism includes a plate-shaped buffer material.

  According to the above embodiment, since the optical base is supported by the plate-shaped buffer material, the camera module can be reduced in thickness and size.

  In one embodiment, the buffer mechanism supports the optical system via a buffer material that sandwiches the first housing.

  According to the embodiment, the buffer mechanism is a buffer material that sandwiches the first housing, and elastically supports the optical base of the optical system in both directions. Therefore, the buffer mechanism is simplified, thinned, and miniaturized. As a result, the camera module can be simplified, reduced in size, and reduced in thickness.

  Even when the shock absorbing material has only one direction, which is the direction in which the shock absorbing material is compressed, the first base is sandwiched between the shock absorbing materials from both sides, and the optical base is supported, so the shock is reduced in two directions. The effect is obtained.

  In one embodiment, the buffer mechanism includes a buffer material between the optical system and the inner surface of the first housing, a buffer material in contact with the outer surface of the first housing, the both buffer materials, The screw includes a screw that is inserted through the first housing and has a tip screwed into a screw hole of the optical system and a head supported by the cushioning material.

  According to the above embodiment, the buffer mechanism includes the buffer material provided on both sides of the first casing, the buffer material is inserted through the buffer material, the tip is screwed into the optical base, and the head is the buffer material. Since it is comprised by the screw supported, a buffer mechanism can be reduced in size.

  In one embodiment, the screw is disposed so as to surround the position of the image of the center of gravity of the optical system projected on the surfaces in three directions substantially orthogonal to the first casing.

  According to the embodiment, the screw and the cushioning material that contacts the head of the screw are arranged so as to surround the position of the image of the center of gravity of the optical system projected on the planes in the three substantially orthogonal directions. Therefore, the optical system can be sufficiently protected by the buffer mechanism against the rotational impact force in all directions caused by the rotational moment of the optical system when the camera module falls while rotating.

  In one embodiment, the screw is disposed at an end portion of a surface in three directions substantially orthogonal to the first casing.

  According to the embodiment, since the screw and the cushioning material that contacts the head of the screw are arranged at the end portions of the surfaces of the first casing in the three orthogonal directions, the rotational impact force is The action on the optical system can be effectively mitigated.

  In one embodiment, the buffer mechanism supports the optical base of the optical system on the first casing in three directions intersecting each other.

  According to the above embodiment, since the buffer mechanism supports the optical base of the optical system to the first casing in three directions intersecting each other, the buffer mechanism can be simplified, reduced in size, reduced in thickness, and reduced in cost. As a result, the camera module can be simplified, reduced in size, reduced in thickness, and reduced in cost. If the optical base is supported on six surfaces, that is, in six orthogonal directions, the buffer mechanism becomes complicated, large, thick, and expensive.

  In one embodiment, the power transmission part includes a leaf spring with a rack having a rack part.

  According to the embodiment, since the power transmission unit includes the leaf spring with a rack, the impact force due to the relatively large weight of the drive mechanism is absorbed by the leaf spring with the rack, and the impact force applied to the optical system is reduced. can do. Moreover, since the leaf spring with rack has a rack portion, it can absorb an impact and can reliably transmit power from the drive mechanism.

  According to the present invention, the camera module itself can be provided with a drop impact resistance, and the camera module can be reduced in size, thickness, and cost.

  Hereinafter, the camera module of the present invention will be described in detail with reference to the illustrated embodiments.

  FIG. 1 is a perspective view of the camera module of this embodiment.

  The camera module 20 mainly includes an optical unit 30, a zoom / focus lens driving unit 40, and an image sensor 50.

FIG. 2 is an exploded perspective view of the camera module 20. In the optical system of the camera module 20, incident light passes through the first imaging lens 21 fixed on the subject side, and is then bent by 90 degrees by the optical path conversion element 22 behind the first imaging lens 21. The light passes through the focus lens 23, the zoom lens 24, and the second imaging lens 25 in this order and travels toward the imaging device 50. The focus lens 23 and zoom lens 24 are first lens holder 32 respectively held by the second lens holder 33, are assembled to slidably optical base 31 in the direction of arrow X ₁ and X _2.

  The optical system includes optical elements such as the first imaging lens 21, the optical path conversion element 22, the focus lens 23, the zoom lens 24, the second imaging lens 25, the first lens holder 32, and the second lens holder 33. The optical parts such as the optical path conversion element base 80, the adjustment mechanism (not shown), and the optical base 31 are shown as a whole, in other words, the optical base 31 and the optical-related parts mounted on the optical base 31.

  The optical unit 30 is elongated along the direction of the optical axis K1 and opens upward, and the zoom / focus lens driving unit 40 is also elongated along the direction of the optical axis K1 and opens downward. A part of the external shape of the camera module 20 main body is configured by closely adhering the opened upper side of the optical unit 30 and the opened lower side of the zoom / focus lens driving unit 40 together.

  3 and 4 show the configuration of the zoom / focus lens driving unit 40. The zoom / focus lens driving unit 40 includes a gear case 41 having a substantially U-shaped cross section that constitutes a part of the second housing 39, and driving mechanisms 42, 45 a, 48 a, 43 provided on the gear case 41. , 46a, 48b. The drive mechanisms 42, 45 a, 48 a, 43, 46 a, 48 b are focus drive mechanisms 42, 45 a, 48 a for driving the focus lens 23 and zoom drive mechanisms 43, 46 a for driving the zoom lens 24. , 48b.

Specifically, in the gear case 41, the arrow _{X 1} along the optical axis _{K 1} in the direction of _{X 2,} the focus drive mechanism 42,45A, focusing motor 42 constituting the 48a, focusing lead screw 45a, A focusing transmission gear 48a (see FIGS. 4 and 7) for transmitting the power of the focusing motor 42 to the focusing lead screw 45a is inserted. Further, in the gear case 41, along the optical axis _{K 1} from the arrow _{X 2} in the direction of the _{X 1,} the zoom driving mechanism 43,46A, zoom motor 43 constituting the 48b, zooming lead screw 46a, and A zoom transmission gear 48b for transmitting the power of the zoom motor 43 to the zoom lead screw 46a is inserted.

  The focus drive mechanisms 42, 45a, and 48a are sandwiched between the gear case 41 and the focus drive unit cover 44a, and are fixed by screws 49a. The zoom drive mechanisms 43, 46a, and 48b are sandwiched between the gear case 41 and the zoom drive mechanism cover 44b and fixed with screws 49b. The outer end portions of the lead screws 45a and 46a are supported by covers 44a and 44b, respectively, while the central end portion is supported by a support portion 41c provided at the center of the gear case 41.

  The focus lead screw 45a is preloaded by a focus lead screw preload spring 47a. The zoom lead screw 46a is preloaded by a zoom lead screw preload spring 47b.

  The gear case 41, the cover 44a, and the cover 44b constitute an example of the second housing 39.

  Next, the configuration of the optical unit 30 will be described with reference to FIGS.

  First, as shown in FIGS. 2, 5, and 6, the optical unit 30 is mounted on a first housing 29, an optical base 31 accommodated in the first housing 29, and the optical base 31. The optical base 31 includes a plurality of optical-related components and a buffer mechanism described later that elastically supports the optical base 31 on the first housing 29.

  More specifically, as shown in FIG. 5, the main guide shaft 34 and the sub guide shaft 35 are fixed by pressing each end toward the optical base 31 by guide pressing springs 81 a to 81 d. The main shaft guide 34 can be adjusted in two directions orthogonal to the optical axis k1 by means of worm screws 70c, 70d and 71a, 71b. On the other hand, the sub-shaft guide 35 can be adjusted only in the direction of the optical axis k2 by a worm screw 70a (only one side is shown) contacting both ends.

The optical base 31 includes a first imaging lens 21, for example, a fixed optical element composed of an optical path changing element 22 and a second imaging lens 25 composed of a prism and a mirror, and a moving lens composed of a focus lens 23 and a zoom lens 24. Has been. The focus lens 23 and the zoom lens 24 are held by a first lens holder 32 and a second lens holder 33, respectively. The first lens holder 32 and the second lens holder 33 are bracket portions 32a and 33a. the main guide shaft 34 slidably fitted in, are slidably mounted in the direction of arrow X ₁ and X ₂ along the main guide shaft 34 and sub guide shaft 35.

  Further, rack springs 36 and 37 having rack portions 36a and 37a are fixed to the bracket portions 32a and 33a of the first lens holder 32 and the second lens holder 33, respectively. The rack portions 36a and 37a are provided so as to mesh with the focus lead screw 45a and the zoom lead screw 46a of the zoom / focus lens driving portion 40, respectively. The rack springs 36 and 37 with racks constitute an example of a power transmission unit.

  Power transmission from the zoom / focus lens drive unit 40 to the optical unit 30 is provided to the focus lead screw 45a and zoom lead screw 46a of the zoom / focus lens drive unit 40 and the plate springs 36, 37 with racks. The rack portions 36a and 37a are elastically engaged with each other. Therefore, an impact is not directly transmitted from the zoom / focus drive unit 40 to the optical unit 30. In the above-described example, the rack portions 36a and 37a are provided on the plate springs 36 and 37 with racks. However, the rack portion is not limited to the plate spring, and a rack portion is provided on another elastic body such as rubber to transmit impact force. May be relaxed.

  The second imaging lens 25 is mounted on the second imaging lens holder 82. The second image pickup lens holder 82 has optical aberrations caused by assembly errors and processing tolerances of each component generated when the first image pickup lens 21, the optical path conversion element 22, the focus lens 23, and the zoom lens 24 are assembled to the optical base 31. In order to cancel, the optical base 31 is fixed by performing a so-called spatial orientation adjustment that is translated or tilted in a direction orthogonal to the optical axis k1. An adhesive is used for fixing at this time. Although not shown, the image sensor 50 shown in FIGS. 1 and 2 also adjusts the spatial orientation for the same reason as the second image pickup lens 25 and adheres only to the optical base 31 and the second image pickup lens holder 82. Fixed with etc.

  6 and 7 show a buffer mechanism provided in the optical unit 30. FIG.

  First, it demonstrates using FIG. A substantially rectangular plate made of rubber, for example, with respect to three surfaces substantially perpendicular to the optical base 31, that is, three surfaces including a bottom surface (bottom portion) 31b and two side surfaces (side walls) 31a and 31c adjacent to each other. The buffer bases 60b, 60a, and 60c are attached, and the optical base 31 to which the substantially rectangular buffer members 60b, 60a, and 60c are attached is housed in the first housing 29. In this way, three substantially orthogonal surfaces of the first casing 29, that is, the bottom surface (bottom portion) 29b, three surfaces including the side surfaces (side walls) 29a and 29c adjacent to each other, the bottom surface 31b of the optical base 31, and The substantially rectangular plate-shaped cushioning materials 60b, 60a, and 60c are disposed between the three surfaces including the two side surfaces 31a and 31c adjacent to each other.

  Further, four through holes (not shown) are provided in the vicinity of the four corners of the bottom surface 29b of the first casing 29, and the rectangular cushioning material 60b is also opposed to the four through holes of the bottom surface 29b. Four through holes 60d are provided. In addition, through holes 29d are provided at both ends of the side surfaces 29a and 29c of the first casing 29, and the rectangular plate-shaped cushioning materials 60a and 60c are also provided with through holes 60d facing the through holes 29d. Provided. Further, on the outer surface side of the first casing 29 and at a position where the total of the eight through holes 29d are provided, for example, disc-shaped buffer materials 611b, 612b, 613b, 614b made of rubber; 611a, 612a ; 611c and 612c are provided. Furthermore, a screw hole 31d is provided at a position of the optical base 31 facing the eight through holes 29d of the first casing 29.

  From the outside of the first housing 29, screws 621b, 622b, 623b, 624b; 621a, 622a; 621c, 622c are connected to the disk-shaped cushioning materials 611b, 612b, 613b, 614b; 611a, 612a; 612c, the through holes 29d of the first casing 29, and the through holes 60d of the rectangular plate-shaped cushioning materials 60b, 60a, 60c are sequentially inserted, and these screws 621b, 622b, 623b, 624b; The tips of 621a, 622a; 621c, 622c are screwed into the screw holes 31d of the optical base 31. As a result, as shown in FIGS. 6 and 7, the bottom 29b of the first casing 29 and the bottom 31b of the optical base 31 have screws 621b, 622b, 623b, and 624b sandwiched by a rectangular plate-shaped cushioning material 60b. The disc-shaped cushioning material 611b, 612b, 613b, 614b is sandwiched between the bottom 29b of the first casing 29 and the heads of the screws 621b, 622b, 623b, 624b. It will be. Therefore, even if the rectangular plate-shaped buffer material 60b and the disk-shaped buffer materials 611b, 612b, 613b, and 614b have a buffering action only in the compression direction, the plate-shaped buffer material 60b and the disk The optical base 31 is supported from both the upper and lower surfaces of the bottom portion 29b of the first casing 29 via the buffer materials 611b, 612b, 613b, and 614b in the shape of a buffer. Is obtained. Similarly, the side wall or side portion 29c of the first casing 29 and the side wall or side portion 31c of the optical base 31 are fastened by screws 621c and 622c with a rectangular plate-shaped cushioning material 60c interposed therebetween, and Disk-shaped cushioning materials 611c and 612c are sandwiched between the side portion 29c of the first casing 29 and the heads of the screws 621c and 622c. Therefore, even if the rectangular plate-shaped cushioning material 60c and the disk-shaped cushioning materials 611c and 612c have a cushioning action only in the compression direction, the rectangular plate-shaped cushioning material 60c and the disk-shaped cushioning material 60c The optical base 31 is supported from both the left and right sides of the side portion 29c of the first casing 29 via the buffer materials 611c and 612c, so that a buffering effect is obtained in both the left and right directions.

  As described above, the rectangular plate-shaped cushioning materials 60b, 60a, 60c, the disk-shaped cushioning materials 611b, 612b, 613b, 614b; 611a, 612a; 611c, 612c, and the screws 621b, 622b, 623b, By arranging 624b; 621a, 622a; 621c, 622c, an example of a buffer mechanism is configured.

  Originally, since the shock absorbing material has an impact mitigating effect only in the compressing direction, it is necessary to provide the shock absorbing mechanism with respect to the six surfaces of the optical base 31. However, optical components are mounted on the upper surface of the optical base 31. The buffer mechanism cannot be provided structurally.

  However, as described above, by configuring the buffer mechanism so as to support the optical base 31 with both surfaces of the first casing 29 sandwiched between the buffer materials, the optical base 31 can only be dropped from the bottom surface direction. Even if it falls from the upper surface direction, an impact relaxation effect can be obtained. More specifically, by providing the buffer mechanism only on the three orthogonal surfaces, it is possible to obtain a buffer effect against impacts in all directions.

  By using the buffer mechanism having the above-described configuration, not only the layout of the entire camera module is simplified, but also the degree of freedom in designing the optical unit 30 is increased, and the camera module 20 can be reduced in size and thickness.

  The diameters of the heads of the screws 621b, 622b, 623b, 624b; 621a, 622a; 621c, 622c are set so that the heads have a disk-like cushioning material 611b, 612b, 613b, 614b; When an impact force is applied in the compressing direction, the force that presses against the disk-shaped cushioning materials 611b, 612b, 613b, 614b; 611a, 612a; 611c, 612c is dispersed. Is preferred. In addition, the positions where the above disk-shaped cushioning materials 611b, 612b, 613b, 614b; 611a, 612a; 611c, 612c and screws 621b, 622b, 623b, 624b; 621a, 622a; One side of the image of the center of gravity and the surface 29b so as to surround the image of the center of gravity of the optical system projected two-dimensionally on each of the three orthogonal surfaces 29b, 29a, 29c of the one housing 29 , 29a and 29c. By doing so, the impact force generated by the rotational moment around the center of gravity of the optical system can be alleviated, so that not only the portable information device falls freely, but also the impact force can be mitigated when it falls while rotating.

  Here, the optical system includes optical elements such as the first imaging lens 21, the optical path conversion element 22, the focus lens 23, the zoom lens 24, the second imaging lens 25, the first lens holder 32, and the second lens holder. This means the optical parts 33 and the like, all the optical related parts such as the optical adjusting mechanism such as the main guide shaft 34 and the sub guide shaft 35, and the optical base 31 on which the optical related parts are mounted.

  The positions where the disk-shaped cushioning materials 611b, 612b, 613b, 614b; 611a, 612a; 611c, 612c, and screws 621b, 622b, 623b, 624b; 621a, 622a; It is preferable to be as far as possible from the image of the center of gravity in order to reduce the impact force on the optical system when the portable information device falls while rotating.

  According to the camera unit 20 configured as described above, the optical unit 30 accommodates the optical base 31, all optical-related components including the optical elements and adjustment mechanisms mounted on the optical base 31, and the optical base 31. The first housing 29 and the buffer mechanism are separated from the zoom / focus lens driving unit 40. The first housing 29 of the optical unit 30 and the second housing 39 of the zoom / focus lens driving unit 40 include a focus lead screw 45a and a rack portion 36a of a plate spring 36 with a rack. The camera module 20 is integrally formed by overlapping so that the zoom lead screw 46a and the rack portion 37a of the leaf spring 37 with rack are elastically engaged with each other.

  Thus, the optical system mounted on the optical unit 30 is separated from the zoom / focus lens driving unit 40 having a relatively large mass, and the focus lens 23, which is a specific optical element of the optical system, The first and second lens holders 32 and 33, which are optical components for the zoom lens 24, and the focus lead screw 45a and the zoom lead screw 46a of the zoom / focus lens driving unit 40 are connected to the leaf spring 36 with a rack. , 37 and the optical base 31 on which the optical system is mounted is elastically supported by the first casing 29 via a buffer mechanism, so that the impact force applied to the optical system is reduced. The buffer mechanism can be reduced in size and thickness.

  By the way, an adhesive is often used for assembling the optical unit 30. As the adhesive, the environmental resistance of the camera module 20 is suppressed, particularly the change in the position of the optical element when left at a high temperature near 80 ° C. In order to achieve this, for example, an epoxy-based adhesive having a low cure shrinkage and a high Young's modulus during curing is used. This type of adhesive is vulnerable to impact, and when the camera module 20 is dropped, the bonded portion may be broken and the optical component may fall off.

  However, as described above, since the optical base 31 is supported on the first housing 29 via the buffer mechanism, shock or vibration is caused when the camera module 20 is dropped on the floor or when the vehicle is transported. Even when is applied, since the shock and vibration are transmitted to the optical base 31 in a relaxed state, the optical unit 30 can be prevented from being damaged.

  The zoom / focus lens driving unit 40 has a so-called box structure in which metal motors 42 and 43 are incorporated in a bulk gear case 41 and ends thereof are fixed by screws 49a and 49b with covers 44a and 44b. Therefore, the metallic motors 42 and 43 supported inside the gear case 41 themselves become rigid members, and the strength of the zoom / focus lens driving unit 40 itself is increased. Therefore, the zoom / focus lens driving unit 40 is hardly damaged even when an impact is applied when the camera is dropped.

  Further, the camera module 20 is not provided with a buffer mechanism for the whole, but is provided only with the optical unit 30, so that the impact force received by the buffer mechanism itself is small, and the buffer mechanism. This is advantageous in terms of reducing the size, thickness and cost of the buffer mechanism itself. Further, in order to reduce the drop impact force received by the buffer mechanism itself, the optical base 31 is made of a lightweight and high-rigidity material such as a magnesium alloy, so that not only can the size and thickness be reduced, but also the static rigidity. Therefore, it is not deformed by an external force applied to the adjustment stage when assembling the optical component, and can be assembled with high accuracy.

  In the embodiment, the buffer mechanism includes the rectangular plate-shaped buffer materials 60b, 60a, 60c, the disk-shaped buffer materials 611b, 612b, 613b, 614b; 611a, 612a; 611c, 612c, and the screws 621b, 622b, 623b, 624b; 621a, 622a; 621c, 622c, the both sides of the first housing 29 are arranged on the rectangular plate-shaped buffer materials 60b, 60a, 60c, and the disk-shaped buffer materials 611b, 612b, 613b, 614b; 611a, 612a; 611c, 612c, but the structure of the buffer mechanism is not limited to this. For example, without using screws, a plate-shaped cushioning material is provided only between the optical base 31 and the first housing 29, and the optical base 31 and the first housing are provided on both sides of the plate-shaped cushioning material. You may make it adhere | attach the body 29 with an adhesive agent.

  Moreover, in the said embodiment, although the buffer material was substantially rectangular or disk shape, and consisted of rubber | gum, the shape and material of a buffer material are not restricted to this, Shapes, such as an ellipse and a polygon, an elastomer, etc. The material may be used.

  As described above, according to the present invention, since the buffer mechanism is provided inside the camera module, the camera module can be generalized, and even when a shock due to dropping or vibration during transportation acts, Not only can the module itself be prevented from being damaged, but also a portable information device equipped with this camera module can be reduced in size, thickness and cost.

  In addition, since the buffer mechanism is provided only in the optical unit that is vulnerable to the shock inside the camera module, the space of the buffer mechanism can be saved, and the camera module itself can be reduced in size and thickness.

It is a perspective view of the camera module of this invention. It is a disassembled perspective view of the camera module of this invention. It is a perspective view which shows the zoom and focus lens drive part of the camera module of this invention. It is a disassembled perspective view which shows the structure of the zoom focus lens drive part of the camera module of this invention. It is a disassembled perspective view which shows the structure of the optical unit of the camera module of this invention. It is a disassembled perspective view which shows the structure of the buffer mechanism employ | adopted as the optical unit of the camera module of this invention. It is sectional drawing which shows the structure of the buffer mechanism employ | adopted as the optical unit of the camera module of this invention. It is a longitudinal cross-sectional view of a prior art example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 20 Camera module 21 1st imaging lens 22 Optical path conversion element 23 Focus lens 24 Zoom lens 25 2nd imaging lens 29 1st housing | casing 30 Optical unit 31 Optical base 32 1st lens holder 33 2nd lens holder 34 Main guide shaft 35 Sub-guide shafts 36, 37 Leaf springs with racks 36a, 37a Rack portion 39 Second housing 40 Zoom / focus lens drive portion 41 Gear case 42 Focus motor 43 Zoom motor 44a Focus drive portion cover 44b Zoom drive portion Cover 45a Focus lead screw 46a Zoom lead screw 47a Focus lead screw pressure spring 47b Zoom lead screw pressure spring 48a Focus transmission gear 48b Zoom transmission gear 50 Imaging element 60a, 60b, 60c rectangular plate-shaped cushioning member 611b, 612b, 613b, 614b, 611a, 612a, 611c,
612c Disc-shaped cushioning material 621b, 622b, 623b, 624b, 621a, 622a, 621c,
622c Screw K1, K2 Optical axis

Claims (8)

A first housing;
An optical system provided in the first casing and including an optical base and a plurality of optical elements mounted on the optical base;
A buffer mechanism for supporting the optical base on the first housing;
A second housing attached to the first housing so as to cover at least a part of the optical system;
A drive mechanism provided on the second housing and for moving a specific optical element in the optical system in the optical axis direction;
A camera module comprising: a power transmission unit that elastically connects the specific optical element and the drive mechanism to transmit power of the drive mechanism to the specific optical element.   2. The camera module according to claim 1, wherein the buffer mechanism includes a plate-shaped buffer material.   3. The camera module according to claim 1, wherein the buffer mechanism supports the optical system via a buffer material sandwiching the first housing. 4.   4. The camera module according to claim 3, wherein the buffer mechanism includes a buffer material between the optical system and an inner surface of the first casing, a buffer material in contact with an outer surface of the first casing, and the both. A camera module comprising: a shock-absorbing material and a first housing; and a screw having a tip screwed into a screw hole of an optical system and a head supported by the shock-absorbing material.   5. The camera module according to claim 4, wherein the screw is disposed so as to surround a position of an image of a center of gravity of the optical system projected onto a plane in three directions substantially orthogonal to the first casing. A camera module characterized by that.   6. The camera module according to claim 5, wherein the screw is disposed at an end portion of a surface in three directions substantially orthogonal to the first casing.   2. The camera module according to claim 1, wherein the buffer mechanism supports the optical base of the optical system on the first casing in three directions intersecting each other. The camera module according to claim 1, wherein the power transmission unit includes a leaf spring with a rack having a rack portion.

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