JP2009139580A - Lens barrel and imaging apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To precisely adjust the optical axis of a lens and to make a housing thinner. <P>SOLUTION: The lens barrel 2 is provided with a locking part 67 that locks the leading-end member 44 of a shaft 14 to the housing 4 in the direction of the axial line G. The lens barrel 2 includes: a screw 51 that is inserted into the through-hole 66 of the locking part 67, with a gap M2 left, and helically engaged with the leading-end member 44; and a plate spring 55 interposed between a head part 51a and locking part 67. A jig connected with the screw 51 is moved, thereby the leading-end member 44 is moved by the gap M2. Consequently, the inclination of the shaft 14 is adjusted and the optical axis L2 is also adjusted. Then, the screw 51 is fastened to the leading-end member 44 by means of the jig and, thereby, the screwing action of the screw 51 and the elastic force of the plate spring 55 cooperate. As a result, the locking part 67 is sandwiched by the leading-end member 44 and plate spring 55, and the shaft 14 is fixed to the housing 4 so that inclination of the shaft 14 is freely adjusted and the jig is made to have the position adjustment function of the shaft 14, thereby easily constructing the housing 4. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a lens barrel and an imaging device applied to, for example, a camera-equipped mobile phone.

As a conventional lens barrel, a lens frame that holds a lens, a guide shaft that guides the movement of the lens frame so that the lens moves along the optical axis direction, and one end portion of the guide shaft that houses the lens frame And a housing in which a guide shaft is eccentrically supported by a bearing (see, for example, Patent Documents 1 to 4). In such a lens barrel, by rotating the bearing, the guide shaft is moved so that the tilt of the guide shaft changes, and the optical axis of the lens is adjusted.
JP 2006-227170 A JP 2006-208554 A JP 2006-309053 A JP 2007-199408 A

  However, in the technique as described above, when the optical axis of the lens is adjusted, the guide axis can only be moved along a fixed trajectory. Therefore, the adjustment of the optical axis of the lens is limited, and the optical axis of the lens is accurate. May not be able to adjust well. In recent lens barrels, it is desired to reduce the thickness of the housing.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a lens barrel and an imaging device that can adjust the optical axis of a lens with high accuracy and can realize a thin housing.

  In order to solve the above problems, a lens barrel according to the present invention includes a lens frame that holds a lens, a guide shaft that guides the movement of the lens frame so that the lens moves along the optical axis direction, and a lens frame. A lens barrel that houses and supports one end of the guide shaft, and the housing is provided with a locking portion that locks the other end of the guide shaft in the axial direction of the guide shaft. A screw member that is inserted in a through-hole formed in the locking portion with a gap and is screwed to the other end, and is interposed between the head portion of the screw member and the locking portion. And an elastic member.

  In this lens barrel, for example, a screwdriver-type jig is connected to the head of the screw member, and the jig is moved, so that the other end portion of the guide shaft (hereinafter simply referred to as a gap between the through hole and the screw member). "The other end" is moved. Thereby, the tilting of the guide shaft is adjusted, and the optical axis of the lens is adjusted. And by tightening the screw member to the other end portion with a jig, the screwing action of the screw member and the elastic force of the elastic member cooperate, and the locking portion is sandwiched between the other end portion and the elastic member, A guide shaft is fixed to the housing. Therefore, by adjusting the position of the jig connected to the screw member, the tilt of the guide shaft can be adjusted freely, and the optical axis of the lens can be adjusted with high accuracy. Furthermore, since the position of the jig is adjusted in this way to adjust the tilt of the guide shaft, the jig can have a function of adjusting the position of the guide shaft, and the housing can be configured easily. Become. As a result, the housing can be thinned.

  Here, it is preferable that the housing is provided with a recess into which one end is fitted with a gap. In this case, by controlling the position of the jig connected to the screw member, not only the tilting of the guide shaft is adjusted, but also the guide shaft in the direction intersecting the axial direction due to the gap between the one end and the recess. Translational movement will also be adjusted. Therefore, the optical axis of the lens can be adjusted with higher accuracy.

  An imaging apparatus according to the present invention includes the lens barrel described above and an imaging element that detects light imaged by the lens.

  Since this imaging apparatus includes the lens barrel described above, the same effect as the above effect, that is, the effect of accurately adjusting the optical axis of the lens and realizing the thinning of the housing is achieved.

  According to the present invention, the optical axis of the lens can be adjusted with high accuracy, and the housing can be thinned.

  DESCRIPTION OF EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. In addition, in each figure, the same code | symbol is attached | subjected to the same or an equivalent part, and the overlapping description is abbreviate | omitted.

  FIG. 1 is a perspective view of an embodiment of an imaging apparatus according to the present invention. As shown in FIG. 1, the imaging apparatus 1 includes a rectangular parallelepiped lens barrel 2 having a rectangular bottom surface and a height shorter than each side of the bottom surface, and an imaging element 3 such as a CMOS. ing. A bending optical system is applied to the lens barrel 2. Thereby, in the imaging apparatus 1, light incident from the subject side along the optical axis L <b> 1 parallel to the height direction (hereinafter simply referred to as “height direction”) Z of the lens barrel 2 is transmitted from the lens barrel 2. The image is bent by 90 ° by the lens barrel 2 along the optical axis L2 parallel to the longitudinal direction (hereinafter, simply referred to as “longitudinal direction”) Y of the bottom surface, and is detected by the imaging device 3.

  2 is an exploded perspective view of the imaging apparatus of FIG. 1, and FIG. 3 is an internal configuration diagram of the imaging apparatus of FIG. As shown in FIGS. 2 and 3, the lens barrel 2 includes a box-shaped housing 4. The housing 4 has an opening 5a that opens toward the image sensor 3 in the longitudinal direction Y, and an opening on one side in a direction X (hereinafter referred to as “width direction”) that is orthogonal to the longitudinal direction Y and orthogonal to the height direction. The main body part 5 in which the opening part 5b to be formed is formed, and the cover part 6 that covers the opening part 5a of the main body part 5 are provided. Each of the main body 5 and the lid 6 is made of, for example, polycarbonate with glass fiber, and is integrally formed by injection molding.

  A light passage hole 5c through which light traveling from the subject side along the optical axis L1 enters the main body portion 5 on the front wall of the main body portion 5 (that is, the wall having the bottom surface on the subject side of the lens barrel 2). A light transmission plate 7 that covers the light passage hole 5 c is attached to the front wall of the main body 5. A lens may be used in place of the light transmission plate 7. In the housing 4, a prism 8 is disposed on the optical axis L1 on the rear side of the light passage hole 5c and bends light incident from the subject side along the optical axis L1 by 90 ° along the optical axis L2. Has been. In the housing 4, a fixed lens 11 positioned on the front side of the image sensor 3 on the optical axis L <b> 2 is disposed. The prism 8 is held by the main body 5, and the fixed lens 11 is held by the lid 6.

  Note that the end of the main body 5 opposite to the image sensor 3 in the longitudinal direction Y is bent in a crank shape on the back wall of the main body 5 (that is, the wall having the bottom surface opposite to the subject of the lens barrel 2). In this way, the cutout portion 5d is formed, so that it is thinner (lower profile) than the other portions of the main body portion 5. As described above, the end of the main body 5 opposite to the image sensor 3 in the longitudinal direction Y can be thinned because the end of the main body 5 has a thickness of the prism 8 disposed therein. This is because it is enough to consider the amount of time.

  Further, in the housing 4, there are a shutter / zoom lens unit 12 positioned on the optical axis L 2 and a zoom focus lens unit 13 positioned between the shutter / zoom lens unit 12 and the fixed lens 11 on the optical axis L 2. Has been placed.

  The shutter / zoom lens unit 12 includes a shutter that selectively passes and blocks light traveling along the optical axis L2, and a zoom lens. The shutter / zoom lens unit 12 includes a cylindrical engaging portion 12a that engages with a guide shaft 14 provided on the opening 5b side with respect to the optical axis L2 in the housing 4, and an optical axis L2 in the housing 4. On the other hand, it has a U-shaped groove-like engaging portion 12b that engages with a rotation-preventing shaft 15 that is provided upright on the opposite side of the opening 5b. Accordingly, the shutter / zoom lens unit 12 can move along the optical axis L2 in a state where the rotation around the optical axis L2 is restricted.

  The zoom focus lens unit 13 includes a zoom focus lens. The zoom focus lens unit 13 includes a cylindrical engaging portion 13a that engages with a guide shaft 16 that is erected on the side of the opening 5b with respect to the optical axis L2 in the housing 4, and a U that engages with a rotation preventing shaft 15. It has a groove-shaped engaging portion 13b. Thereby, the zoom focus lens unit 13 can move along the optical axis L2 in a state where the rotation around the optical axis L2 is restricted. The guide shaft 14 and the guide shaft 16 are juxtaposed in the height direction Z.

  A drive unit 17 is disposed in the opening 5 b of the main body 5. FIG. 4 is a perspective view of a drive unit of the imaging apparatus of FIG. As shown in FIG. 4, the drive unit 17 has a support member 18 including a rectangular thin plate-like mounting portion 18 a and rectangular thin plate-like support portions 18 b and 18 c erected at both ends in the longitudinal direction. Yes. The support member 18 is integrally formed by bending a stainless steel thin plate.

  A stepping motor (drive motor) 21 is attached to the outer surface of the support portion 18b. Both ends of the lead screw 22 of the stepping motor 21 are pivotally supported by support portions 18b and 18c, and a driven nut 23 having a convex portion 23a is screwed into a portion between the support portions 18b and 18c of the lead screw 22. Has been. On the other hand, a stepping motor (drive motor) 24 is attached to the outer surface of the support portion 18c. Both ends of the lead screw 25 of the stepping motor 24 are pivotally supported by support portions 18b and 18c, and a driven nut 26 having a convex portion 26a is screwed into a portion between the support portions 18b and 18c of the lead screw 25. Has been. The lead screw 22 and the lead screw 25 are juxtaposed in the standing direction of the support portions 18b and 18c.

  As shown in FIGS. 2 and 3, the drive unit 17 is disposed in the opening 5 b of the main body 5 so that the standing direction of the support portions 18 b and 18 c coincides with the height direction Z. 18 a is attached to the main body 5 by being screwed to the front wall of the main body 5. As described above, in the drive unit 17, the stepping motor 21 and the stepping motor 24 are alternately arranged so that the lead screw 22 and the lead screw 25 are close to each other. As a result, the drive unit 17 contributes to the thinning of the main body 5 and the lens barrel 2.

  The convex portion 23 a of the driven nut 23 screwed into the lead screw 22 is fitted in the concave portion of the engaging portion 12 c of the shutter / zoom lens unit 12. Thereby, when the lead screw 22 is rotated by the stepping motor 21, the shutter / zoom lens unit 12 moves along the optical axis L2. On the other hand, the convex portion 26 a of the driven nut 26 screwed into the lead screw 25 is fitted in the concave portion of the engaging portion 13 c included in the zoom focus lens unit 13. Thus, when the lead screw 25 is rotated by the stepping motor 24, the zoom focus lens unit 13 moves along the optical axis L2.

  A circuit board 27 provided with an image pickup device 3 located on the rear side of the fixed lens 11 on the optical axis L2 on the inner surface is attached to the lid portion 6 of the housing 4. A shutter drive circuit, a motor drive circuit, and the like are also provided on the inner surface of the circuit board 27, and a connector connection port 28 for inputting and outputting electrical signals to the circuit board 27 is provided on the outer surface of the circuit board 27. It has been. Each of the stepping motors 21 and 24 and the motor drive circuit of the drive unit 17 is a flexible printed circuit board (hereinafter referred to as an outer surface of the side wall facing the opening 5a and the outer surface of the side wall facing the opening 5b in the main body 5). (Referred to as “FPC”) 31. The shutter and the shutter drive circuit of the shutter / zoom lens unit 12 are electrically connected by the FPC 32 extending to the outer surface of the side wall of the main body 5 facing the opening 5b and the FPC 31 electrically connected to the FPC 32. ing.

  The drive unit 17 disposed in the opening 5b of the main body 5 and the FPC 31 disposed on the outer surface of the side wall facing the opening 5a in the main body 5 are formed by bending a thin plate made of stainless steel into an L shape. It is covered by an integrally formed exterior cover 33. Further, the FPC 31 disposed on the outer surface of the side wall facing the opening 5b in the main body 5 and the circuit board 27 attached to the lid 6 of the housing 4 are formed by bending a thin plate made of stainless steel into an L shape. It is covered with an integrally formed exterior cover 34.

  The exterior cover 33 and the exterior cover 34 are detachably engaged with each other at a corner where the side wall facing the opening 5 a and the side wall facing the opening 5 b intersect in the main body 5. Pinned to the lid portion 6 of the housing 4 at a corner portion sandwiched between the portion 5a and the opening portion 5b. The exterior cover 34 is electrically connected to the ground terminal of the circuit board 27. Further, the exterior covers 33 and 34 are formed on the outer surface of the front wall and the outer surface of the main body 5 by vapor deposition or the like. The metal film is electrically connected. Thereby, each component of the imaging device 1 is covered with the electromagnetic shield. A portion of the exterior cover 34 corresponding to the connector connection port 28 of the circuit board 27 is cut out so that the connector can be accessed with respect to the connector connection port 28.

  Next, the guide shaft 14 described above will be described in detail.

  As shown in FIG. 3, the guide shaft 14 guides the movement of the shutter / zoom lens unit 12 so that the shutter / zoom lens unit 12 moves along the direction of the optical axis L2. The guide shaft 14 has a shaft body 41 and a tip member 44.

  The shaft body 41 is arranged in the main body portion 5 of the housing 4 with its axis G parallel to the optical axis L2 (that is, along the longitudinal direction Y). Further, the engaging portion 12 a of the shutter / zoom lens unit 12 is slidably engaged with the shaft body 41. A base end portion (one end portion) 41 a which is a rear end portion of the shaft body 41 is fitted and supported in the recess 42 of the main body portion 5 of the housing 4 with a gap M1 therebetween. The concave portion 42 is provided on the opening 5a side of the main body 5 with respect to the fixed lens 11, and is open forward. An adhesive (not shown) is filled from the filling port (not shown) of the main body 5 around the base end 41 a in the recess 42, and the base end 41 a is fixed to the recess 42.

  5 is a perspective view showing a notch portion side of the imaging apparatus of FIG. 1, and FIG. 6 is an enlarged cross-sectional view showing a main part of a lens barrel in the imaging apparatus of FIG. As shown in FIG. 6, the tip member 44 is fixed to the tip portion 41 b of the shaft body 41 and constitutes the tip portion (other end portion) of the guide shaft 14. The tip member 44 has a substantially cubic shape, and a screw hole 61 for screwing a screw (screw member) 51 described later is provided coaxially with the shaft body 41 on the tip surface 44a.

  As shown in FIG. 3, the tip member 44 is housed in a recess 45 provided on the opening 5 a side of the prism 8 in the main body 5 and opening rearward. As shown in FIG. 6, the tip end surface 44 a of the tip member 44 is in contact with the bottom surface 45 a of the recess 45. That is, the tip member 44 is locked to the locking portion 67 that forms the bottom surface 45 a of the recess 45 in the main body 5. Note that the locking portion 67 here also functions as an outer wall of the housing 4.

  Further, in the state where the tip member 44 is accommodated in the recess 45, the periphery of the tip member 44 in the recess 45 is filled with an adhesive (not shown), whereby the tip member 44 is placed in the recess 45. Is fixed.

  The screw 51 is inserted into the circular through hole 66 formed in the locking portion 67 with a gap M2 therebetween, and is screwed into the screw hole 61 of the tip member 44. The head 51a of the screw 51 is provided with an insertion port 62 (here, a plus type) for inserting a jig 63 (see FIG. 7). As shown in FIGS. 5 and 6, a leaf spring (elastic member) 55 is interposed between the head 51 a of the screw 51 and the locking portion 67. The leaf spring 55 urges the head 51a of the screw 51 toward the front side in the axis G direction. In this embodiment, as described above, the tip member 44 in the recess 45 is filled with an adhesive to fix the tip member 44 in the recess 45, but instead of or in addition to this, An adhesive may be filled around the screw 51 or the leaf spring 55.

  As shown in FIG. 7, the jig 63 includes a driver (screwdriver) portion 63a and a control portion 63b. The driver portion 63 a has a shape corresponding to the insertion port 62 at the tip. The controller 63b controls the position of the driver 63a by moving it, and includes a micrometer, for example.

  Next, adjustment of the optical axis L2 in the lens barrel 2 of the imaging device 1 will be described. In the lens barrel 2, for example, in a manufacturing / assembly process, first, the screwdriver 63 a of the jig 63 is inserted into the head 51 a of the screw 51, and the jig 63 is connected to the screw 51.

  Subsequently, the driver 63a of the jig 63 is moved while observing an image picked up by the image pickup device 3. At this time, since the gap M2 is secured between the through hole 66 and the screw 51, the distal end member 44 of the guide shaft 14 is moved within the allowable range of the gap M2, and the guide shaft 14 centered on the base end portion 41a. The fall of is adjusted. Further, since the gap M1 is secured between the base end portion 41a and the recess 42, the movement of the driver portion 63a causes the guide shaft 14 to move in the height direction Z and the width direction X. The height direction Z and width direction X positions are adjusted. Therefore, the optical axis L2 is adjusted.

  When the imaged image is in an optimal state, the screw 51 is tightened to the tip member 44 by the driver portion 63a of the jig 63, and the screwing action of the screw 51 and the elastic force (biasing force) of the leaf spring 55 are obtained. The engaging portion 67 is sandwiched between the distal end surface 44 a of the distal end member 44 and the leaf spring 55. At the same time, the concave portions 42 and 45 are filled with an adhesive. Thereby, the guide shaft 14 is fixed to the housing 4.

  As described above, according to this embodiment, by adjusting the position of the jig 63 connected to the screw 51, the tilt of the guide shaft 14 can be freely adjusted, and the optical axis L2 can be adjusted with high accuracy. Become. That is, in the lens barrel 2, the position of the guide shaft 14 can be adjusted as desired with one screw 51, and the guide shaft 14 can be fixed at any position in the height direction Z and the width direction X. It becomes.

  Furthermore, since the tilt of the guide shaft 14 is adjusted by adjusting the position of the jig 63 as described above, the jig 63 can have a position adjusting function for adjusting the position of the guide shaft 14. Therefore, the housing 4 can be configured easily, and the housing 4 can be thinned.

  Further, in the present embodiment, as described above, the base end portion 41a of the guide shaft 14 is fitted into the concave portion 42 of the main body portion 5 with a gap M1 therebetween. Therefore, by controlling the position of the jig 63, not only the tilt of the guide shaft 14 is adjusted, but also the guide shaft 14 in the direction (height direction Z and width direction X) intersecting the axis G direction of the guide shaft 14. The translational movement can also be adjusted. As a result, the optical axis of the lens can be adjusted with higher accuracy.

  The lens barrel 2 of the present embodiment is configured such that the optical axis L2 can be easily adjusted by adjusting the optical axis of the optical system of the shutter / zoom lens unit 12. That is, the guide shaft 14 guides the movement of the optical system having the highest contribution of the optical axis L2 adjustment.

  The present invention is not limited to the embodiment described above. For example, in the above embodiment, the guide shaft 14 has the tip member 44, but this tip member may not be provided. In this case, the screw 51 is directly screwed to the tip surface of the shaft body 41. Moreover, in the said embodiment, although the base end part 41a of the shaft 41 was fitted in the recessed part 42 of the housing 4 in the state which opened the clearance gap M1, you may fit without leaving a clearance gap. Even in this case, the optical axis of the lens can be adjusted.

  Moreover, in the said embodiment, although the leaf | plate spring 55 was provided, it is not limited to this, You may provide a various elastic member. In the above embodiment, the screw 51 is tightened in the screw hole 61. However, the screw 51 may be tightened while being screwed (so-called self-tapping). Further, an adhesive may be applied so that the screw 51 is covered in order to fix the screw 51 to the main body 5.

  Further, each stepping motor 21, 24 is not limited to the case where it is indirectly attached to the housing 4 via the support member 18, and may be directly attached to the housing 4. The lens barrel 2 is not limited to the one to which the bending optical system is applied, and may be one to which a retractable optical system or the like is applied.

It is a perspective view of one embodiment of an imaging device concerning the present invention. It is a disassembled perspective view of the imaging device of FIG. It is an internal block diagram of the imaging device of FIG. It is a perspective view of the drive unit of the imaging device of FIG. It is a perspective view which shows the notch part side of the imaging device of FIG. It is an expanded sectional view which shows the principal part of the lens barrel of the imaging device of FIG. It is explanatory drawing about the optical axis adjustment in the lens barrel of the imaging device of FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Imaging device, 2 ... Lens barrel, 3 ... Imaging element, 4 ... Housing, 12 ... Shutter / zoom lens unit (lens, lens frame), 14 ... Guide shaft, 41a ... Base end (one end of guide shaft) ), 42... Recess, 44. Tip member (the other end of the guide shaft) 51. Screw (screw member) 51 a. Head, 55. Plate spring (elastic member) 66. Part, G: axis of guide shaft, L2: optical axis, M1, M2: gap.

Claims (3)

A lens frame that holds the lens; a guide shaft that guides the movement of the lens frame so that the lens moves along the optical axis direction; and a housing that houses the lens frame and supports one end of the guide shaft. A lens barrel comprising:
The housing is provided with a locking portion that locks the other end portion of the guide shaft in the axial direction of the guide shaft,
A screw member that is inserted in a state where there is a gap with respect to the through hole formed in the locking portion, and screwed into the other end portion;
A lens barrel comprising: an elastic member interposed between the head of the screw member and the locking portion.   The lens barrel according to claim 1, wherein the housing is provided with a recess into which the one end is fitted with a gap. The lens barrel according to claim 1 or 2,
An imaging device comprising: an imaging element that detects light imaged by the lens.

Images