JP2012233971A - Manufacturing method for image pickup apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method for image pickup apparatuses capable of easily manufacturing an image pickup apparatus in a short time.SOLUTION: A weight 43 in one end side of an actuator 4 in which movable lens groups 21 and 22 are engaged with a drive shaft 42 at a predetermined frictional force, is inserted in an insertion recess 515 provided in a rear frame 51. The tip end of the drive shaft 42 that forms the other end of the actuator 4 is inserted in an adjustment hole provided in the front frame 52 so as to be swingable, and a sensor substrate 7 is fixedly mounted on the rear frame 51 with the tip of the drive shaft swingably inserted in the adjustment hole. After that, the axial inclination of the drive shaft 42 of the actuator 4 to the sensor substrate 7 is adjusted.

Description

  The present invention is a small-sized image pickup device that is suitably used for an image pickup device of a mobile phone, in particular, a drive mechanism comprising a SIMDM (Smooth Impact Drive Mechanism (registered trademark)) in order to realize functions such as autofocus and zoom. The present invention relates to a method of manufacturing an imaging device using an actuator (actuator).

  As a small lens unit used in the imaging device of the cellular phone, a lens unit using the actuator as a drive mechanism has been put into practical use. This actuator transmits expansion and contraction of a piezoelectric element, which is an electromechanical conversion element, to a drive shaft, and moves a moving lens group engaged with the drive shaft with a predetermined frictional force when the piezoelectric element is expanded and contracted. It is moved using the speed difference. More specifically, for example, by slowly extending the drive shaft, the moving lens group that is frictionally engaged with the drive shaft also moves. On the other hand, if the drive shaft is instantaneously reduced to exceed the predetermined friction force, The moving lens group is left in the extended position. By repeatedly performing such extension and contraction of the drive shaft, the actuator can move the movable lens group in the axial direction of the drive shaft.

  In addition, when the actuator is tilted particularly when the drive shaft is held on the frame, a phenomenon that the focus state of the captured image is different at both ends of the image, so-called one-side blurring, occurs. For this reason, when the imaging apparatus is required to have high performance corresponding to the increase in the number of pixels, it is necessary to adjust the inclination of the drive shaft in the axial direction with respect to the frame when the drive shaft is held in the frame.

  For example, Patent Document 1 discloses a technique for adjusting the axial inclination of the drive shaft with respect to the frame. In this device, an inclination adjustment mechanism is used to adjust the inclination of the drive shaft with respect to a predetermined reference line of the frame. The tilt adjusting mechanism includes a first cylindrical portion and a second cylindrical portion that is eccentric with respect to the first cylindrical portion, and the second cylindrical portion is inserted at the tip of the drive shaft. The outer diameter of the first cylindrical portion is regulated by the frame, and the inclination of the drive shaft can be adjusted by rotating the first cylindrical portion.

JP 2009-25403 A

  However, when the drive shaft is held on the frame, as in the case described in Patent Document 1, even when the axial inclination of the drive shaft with respect to the frame can be adjusted, when the sensor substrate is attached to the frame, On the other hand, when the sensor substrate is mounted in a tilted state, the drive shaft is tilted with respect to the sensor substrate. For this reason, for example, the tilt of the drive shaft with respect to the frame when the actuator is held on the frame as in the above-mentioned Patent Document 1, and further the tilt of the sensor substrate with respect to the frame when the sensor substrate is attached to the frame. In many cases, adjustment is performed, and it takes time for such adjustment, and as a result, time is required for manufacturing. Furthermore, in the thing of the said cited reference 1, although the direction of inclination can be changed, since the amount of inclination is decided by eccentricity, it cannot change, but the problem of giving an inclination to a drive shaft on the contrary is given. There is.

  An object of the present invention is to provide a manufacturing method of an imaging device that can be easily manufactured in a shorter time.

  In order to solve the above-described problems, the present invention provides an actuator having a drive shaft connected to an electromechanical transducer and having a movable lens group engaged with a predetermined frictional force in a frame. A method of manufacturing an imaging device in which both ends are held by the frame and a sensor substrate having an imaging element is fixedly attached to the frame, wherein the actuator is disposed in the frame, and the sensor substrate is mounted on the frame. Provided is a method for manufacturing an imaging device, wherein the imaging device is fixedly attached to the frame, and thereafter, the tilt of the drive shaft of the actuator is adjusted with respect to the sensor substrate.

  According to this, after the sensor substrate is fixedly attached to the frame, the axial inclination of the drive shaft of the actuator is adjusted with respect to the sensor substrate. Therefore, the adjustment of the inclination of the drive shaft of the actuator in the axial direction can be completed in one time, the number of processes can be reduced, and the manufacturing can be performed in a short time.

  In another aspect, in the method of manufacturing the imaging device, the actuator is disposed in the frame so that one end can be swung with the other end of the actuator disposed on the sensor substrate side as a fulcrum. The inclination can be adjusted by swinging one end of the actuator.

  According to this, since the adjustment of the inclination is performed by swinging one end of the actuator, the adjustment of the inclination can be easily performed.

  In another aspect, in the manufacturing method of the imaging apparatus, the tip of the drive shaft forms the one end, and the frame is provided with an adjustment hole into which the tip of the drive shaft is inserted, and the adjustment By inserting the tip of the drive shaft into the hole, one end of the actuator can be swung, and after adjusting the inclination, between the outer periphery of the tip of the drive shaft and the inner peripheral wall of the adjustment hole The tip of the drive shaft can be held on the frame by curing the adhesive filled in the frame.

  According to this, after adjusting the inclination, the adhesive filled between the outer periphery of the drive shaft of the actuator and the inner peripheral wall of the adjustment hole is cured, and the actuator drive shaft is held by the frame. The play between the movable lens group engaged with the drive shaft and the frame can be eliminated, and the movement and rotation of the movable lens group due to the play between both can be suppressed. Thereby, deterioration of optical performance can be prevented. Further, it is possible to prevent dust and dirt from entering between the outer periphery of the drive shaft of the actuator and the inner peripheral wall of the adjustment hole, and to reduce the possibility that smooth sliding of the moving lens group is hindered.

  In another aspect, the tilt of the drive shaft of the actuator can be adjusted based on an image signal output from the sensor substrate in the method for manufacturing the imaging device.

  According to this, the phenomenon that the focus state of the captured image is different at both ends of the image, that is, so-called one-side blur can be reliably prevented.

  The present invention can provide a method of manufacturing an imaging device that can be easily manufactured in a shorter time.

It is a perspective view of an imaging device manufactured by the manufacturing method of the present invention. It is a disassembled perspective view of the imaging device of FIG. FIG. 4A is a cross-sectional view of a state in which the weight of the actuator is inserted into the insertion recess of the rear frame, and FIG. 4B is an illustration of the first group unit engaged with the drive shaft of the actuator. (C) is a sectional view of a state in which the front frame is locked to the rear frame, and (d) is a sectional view of the state in which the sensor substrate is attached to the rear frame. It is sectional drawing at the time of adjusting the inclination of the drive shaft of an actuator using the inclination adjustment jig | tool which has an inclination operation member. It is sectional drawing to which the principal part of FIG. 4 was expanded. It is sectional drawing of the state which made the flame | frame hold | maintain the front-end | tip of the drive shaft of an actuator with the adhesive agent.

  FIG. 1 is a perspective view of an imaging apparatus 1 according to an embodiment manufactured by the manufacturing method of the present invention, and FIG. 2 is an exploded perspective view of FIG. As shown in FIGS. 1 and 2, the imaging apparatus 1 includes a second group unit 2 that is a moving lens unit, a third group unit 3a and a first group unit 3b that are fixed lens units, and a second group unit. Actuators (ultrasonic linear actuators) 4 for driving 2 in the optical axis direction, housings 51, 52, 53 for accommodating the first to third group units 2, 3 a, 3 b and the actuator 4, and the sensor substrate 7 And. The imaging device 1 is preferably mounted on, for example, a mobile phone terminal device.

  The second group unit 2 includes optical elements 21 and 22 that constitute a moving lens group, a light shielding plate 24a disposed between the optical elements 21 and 22, and a second group unit holder that holds the optical elements 21 and 22. 25.

  The optical elements 21 and 22 are made of, for example, a plastic lens, and include a lens portion 211 on the inner diameter side that forms an optical path, and a holding portion 212 that holds the lens portion 211 from the outer peripheral side, and these are integrally molded.

  As shown in FIG. 5, the second group unit holder 25 holds the holding portions 212 of the optical elements 21 and 22 on the inner peripheral side, and the outer peripheral side of the second group unit holder 25 is an actuator 4 described later. The drive shaft 42 is slidably engaged with a predetermined frictional force.

  The third group unit 3a includes an optical element 31a constituting a fixed lens group as shown in FIG. Like the optical elements 21 and 22 of the second group unit 2, the optical element 31a is made of, for example, a plastic lens, and is formed by integrally molding a lens portion 311a and a holding portion 312a.

  As shown in FIG. 5, the third group unit 3 a is held immovably by a rear frame 51, which will be described later, which is a holding member, and is arranged on the rear side of the second group unit 2.

  The first group unit 3b includes optical elements 31b and 31c constituting a fixed lens group as shown in FIG. 2, and light shielding plates 24b and 24c disposed between the optical elements 31b and 31c and on the front side, respectively. A first group unit holder 26 holding the optical elements 31b and 31c.

  Similar to the optical element 31a of the third group unit 3a, the optical elements 31b and 31c are made of, for example, a plastic lens, and a lens portion 311 and a holding portion 312 are integrally molded.

  As shown in FIG. 5, the first group unit holder 26 holds the holding portions 312 of the optical elements 31 b and 31 c on the inner peripheral side, and the outer peripheral side is held immovably by a front frame 52 to be described below. It is arranged on the front side of the group unit 2.

  For convenience of explanation, in FIG. 2, the optical elements 21 and 22 of the second group unit 2 and the optical elements 31 b and 31 c of the first group unit 3 b are each represented by two, and in FIGS. It is represented by one. 3 to 6, the light shielding plates 24a and 24b are omitted.

  The actuator 4 constitutes a driving mechanism for the second group unit 2 including the moving lens groups 21 and 22. For example, the actuator 4 is suitable for miniaturization previously proposed in Japanese Patent Laid-Open No. 2001-268951. It is called a SIDM (Smooth Impact Drive Mechanism (registered trademark)) actuator. In the actuator 4, a weight 43 is connected to the other end of a piezoelectric element 41 that is an electromechanical conversion element that expands and contracts in the axial direction, a drive shaft 42 is connected to one end of the piezoelectric element 41, and the axial direction of the piezoelectric element 41 Due to this vibration, the drive shaft 42 reciprocates and the holding member 24 of the second group unit 2 is engaged with the drive shaft 42 with a predetermined frictional force, whereby the second group unit 2 is moved in the optical axis direction. The

  More specifically, in this actuator 4, the displacement of the piezoelectric element 41 becomes a triangular wave by giving a rectangular wave with a predetermined duty ratio to the piezoelectric element 41, and the amplitude increases and decreases by changing the duty ratio of the rectangular wave. A triangular wave with a different slope is generated. The drive mechanism of the actuator 4 utilizes this. For example, when the drive shaft 42 is vibrated slowly, the second group unit 2 that is frictionally engaged with the drive shaft 42 also moves in response to the vibration and instantly exceeds the predetermined frictional force. When the drive shaft 42 is vibrated, the second group unit 2 is left as it is. The second group unit 2 can be moved in the axial direction of the drive shaft 42 by repeatedly performing such vibration in the axial direction of the drive shaft 42.

  The weight 43 is for generating a displacement due to expansion / contraction of the piezoelectric element 41 only on the drive shaft 42 side. In this embodiment, the weight 43 is formed of a cylindrical shape having an outer diameter that protrudes in the outer circumferential direction over the entire circumference of the piezoelectric element 41.

  If the other end of the piezoelectric element 41 is attached to the casings 51, 52, and 53, and the same function as the weight 43 can be exhibited, the weight 43 is It may be omitted.

  The piezoelectric element 41 is formed by laminating a plurality of piezoelectric layers and, as shown in FIG. 2, electrodes 411 and 412 of each piezoelectric layer are commonly drawn on a pair of side surfaces. The side electrodes 411 and 412 are connected to external connection terminals 46 and 47 via individual lead wires 44 and 45, respectively. The front ends of the external connection terminals 46 and 47 are soldered to a printed circuit board on the terminal device side of the mobile phone, or are fitted into a connector mounted on the printed circuit board.

  The drive shaft 42 is formed of a cylindrical shape. As shown in FIG. 5, the second group unit holder 25 of the second group unit 2 slides on the drive shaft 42 with a predetermined frictional force via the L-shaped spring member 6 shown in FIG. It is movably engaged.

  As shown in FIG. 2, the housing includes frames 51 and 52 and a front cover 53. The frame includes a rear frame 51 that is a resin-molded product and a front frame 52 that is combined with the frame 51, which are locked to each other to form a box, and the second group unit is formed therein. The second and third group units 3a and the actuator 4 are accommodated at least.

  The frames 51 and 52 are made of a resin molded product having a shape in which the box formed by them is divided into two before and after being in the optical axis direction, and the side walls of the box have no through holes. The box is formed in an airtight manner.

  The rear frame 51 is generally formed of a rectangular shape, and is provided with a holding cylinder 514 whose axial direction is extended in the front-rear direction. The inner peripheral side of the holding cylinder 514 becomes a fitting hole 511 to hold the third group unit 3a.

  Further, an insertion recess 515 into which the weight 43 of the actuator 4 is inserted is provided on the outer peripheral side of the holding cylinder 514. The inner diameter of the insertion recess 515 is set to be substantially the same as the outer diameter of the weight 43, so that the weight 43 just enters the insertion insertion recess 515 so that there is substantially no gap.

  The external connection terminals 46 and 47 are attached to the outer periphery of the rear frame 51 as shown in FIG.

  As shown in FIG. 2, the front frame 52 includes side walls 521 extending rearward from the entire outer periphery of the rectangular front plate 522, and the second group unit 2 and the actuator 4 are accommodated therein by these side walls 521. An accommodating portion to be partitioned is formed.

The side wall 521 is provided with a locking piece 521b having elasticity as a locking portion for locking to the rear frame 51. On the front plate 522, the first group unit 3b is arranged and externally provided. The opening 523 which faces is formed. In addition, an adjustment hole 526 into which the distal end portion of the drive shaft 42 forming one end of the actuator 4 is inserted is provided at one corner portion of the front frame 52 on the outer peripheral side of the opening 523.

  As shown in FIG. 3C, the adjustment hole 526 has a diameter R2 larger than the outer diameter R1 of the drive shaft 42, and the tip of the drive shaft 42 inserted into the adjustment hole 526. A predetermined gap 526a is formed between the outer periphery of the drive shaft 42 and the inner peripheral wall of the adjustment hole 526 so that the tip of the drive shaft 42 can move in the radial direction (outer peripheral direction).

  In this embodiment, the outer diameter R1 of the drive shaft 42 is about 800 μm, whereas the diameter R2 of the adjustment hole 526 is about 900 μm.

  The gap 526a is filled with the adhesive 8 so that the drive shaft 42 after the tilt adjustment with respect to the sensor substrate 7 is completed as will be described later. Examples of the adhesive 8 include an ultraviolet curable material and a thermosetting material. However, various adhesives can be used without being limited to these exemplified adhesives.

  Returning to FIG. 2, the front cover 53 is a sheet metal processed product provided on the electromagnetic shield and the appearance (design). After the frames 51 and 52 are assembled, they are covered from the front frame 52 side and provided on the side wall 531. The locking claws 531a are fixed to the front frame 52 by fitting into the locking recesses 521a formed on the side walls 521 of the front frame 52, respectively.

  Next, the sensor substrate 7 will be described. As shown in FIGS. 5 and 6, the sensor substrate 7 includes a rectangular plate-like substrate body 71 and an image sensor 72 disposed on the front side of the substrate body 71. The image sensor 72 includes a CCD type or CMOS type image sensor.

  In this embodiment, the substrate body 71 is made of a synthetic resin plate, and is fixedly attached to the rear end of the rear frame 51 by a fixing means such as an adhesive. In this state, the image sensor 72 is disposed on the rear side of the third group unit 3a.

  Next, a method for manufacturing the imaging device 1 configured as described above will be described. First, as shown in FIG. 3A, the weight 43 of the actuator 4 is inserted into the insertion recess 515 of the frame 51 after the third group unit 3a is attached.

  Next, as shown in FIG. 3B, the second group unit 2 is engaged with the drive shaft 42 of the actuator 4. Thereafter, as shown in FIG. 3C, the front frame 52 to which the first group unit 3b is attached is attached to the rear frame 51 so that the tip of the drive shaft 42 of the actuator 4 is inserted into the adjustment hole 526. Lock.

  In this state, a predetermined gap 526 a is formed between the outer periphery of the drive shaft 42 of the actuator 4 and the inner peripheral wall of the adjustment hole 526, and the actuator 4 has a weight 43 that forms the other end (rear end). The tip of the drive shaft 42 that forms one end (front end) with the fulcrum as a fulcrum can be swung.

  Thereafter, as shown in FIG. 3D, the sensor substrate 7 is fixedly attached to the rear end of the rear frame 51 with an adhesive. As a result, the tilt-unadjusted imaging device 10 before adjusting the tilt of the drive shaft 42 is obtained.

  Next, the tilt adjustment jig 9 is used to adjust the tilt of the drive shaft 42 of the actuator 4 in the tilt-unadjusted imaging apparatus 10. Here, the inclination adjusting jig 9 will be described with reference to FIG. The tilt adjusting jig 9 generally includes a first jig 91 and a second jig 92 facing the first jig 91 in the front-rear direction.

  The first jig 91 includes a substrate receiving portion 91 a that receives the rear surface side of the substrate body 71 of the sensor substrate 7 attached to the rear frame 51.

  The second jig 92 includes a second jig main body 93, an operation member 94 for operating the actuator 4, and an adhesive filling portion (not shown). The second jig body 93 includes a pressing portion 93 a that presses the front frame 52 via the first group unit holder 26.

  As shown in FIG. 5, the tilt operation member 94 is formed of a rod-like body, and includes a contact portion 94 a that contacts the distal end surface of the drive shaft 42 of the actuator 4 at the distal end portion. The tilt operation member 94 is disposed on the second jig body 93 so as to be movable in the axial direction (XX direction in FIG. 5) and in a direction perpendicular to the axial direction.

  The unadjusted imaging device 10 is arranged between the first jig 91 and the second jig 92 of the tilt adjusting jig 9 configured as described above, and the substrate receiving portion 91a of the first jig 91 is arranged. And the pressing portion 93a of the second jig 92 hold the sensor substrate 7 and the frames 51 and 52 of the imaging apparatus 10 with no tilt adjustment while moving the tilt operation member 94 toward the actuator 4 in the axial direction. Thus, the tilt operation member abutting portion 94 a is brought into contact with the tip surface of the drive shaft 42 of the actuator 4.

  Further, in the state where the tilt-unadjusted imaging device 10 is held as described above, an adhesive filling portion (not shown) is arranged in the vicinity of the adjustment hole 526 of the front frame 52, and the adjustment hole extends from the adhesive filling portion. Filler 8 (see FIG. 6) is filled in a gap 526 a between the inner peripheral wall of 526 and the outer periphery of drive shaft 42.

  Next, while monitoring the captured image appearing on the image sensor 72 through the first to third group units 2, 3a, 3b, the tilt operation member 94 is made perpendicular to the axial direction based on the captured image so that the image quality is the best. The tip of the drive shaft 42 of the actuator 4 is swung by moving in the direction, thereby adjusting the tilt of the drive shaft 42 of the actuator 4 relative to the sensor substrate 7 (the tilt of the axis O). In this way, based on the image signal from the sensor substrate 7, the inclination of the drive shaft 42 in the axial direction is adjusted so that the focus state of the peripheral portion of the image is substantially the same (so as not to cause one-side blur). To do.

  After the tilt adjustment, the filled filler 8 is irradiated with ultraviolet rays and cured. Accordingly, the front end of the drive shaft 42 that is one end side in the axial direction of the actuator 4 can be held on the front frame 52. In this state, the imaging device 1 in a state where the front cover 53 is not attached can be obtained.

  Thereafter, the tilt operation member 94 is raised and separated from the actuator 4, and the imaging device 1 with the front cover 53 not attached is taken out from the tilt adjustment jig 9 (FIG. 6). And the imaging device 1 shown in FIG. 1 can be obtained by mounting the front cover 53 so as to cover the front frame 52.

  If the image pickup apparatus 1 is manufactured as described above, it is not necessary to adjust the axial inclination of the drive shaft with respect to the frame, and the adjustment of the axial inclination of the drive shaft of the actuator can be adjusted only once. The manufacturing process can be reduced as compared with the conventional method, and the manufacturing process can be performed in a shorter time than the conventional method.

  In addition, since the adjustment of the inclination of the drive shaft of the actuator in the axial direction is performed by swinging the tip of the drive shaft of the actuator, the adjustment of the inclination can be easily performed.

  In addition, after adjusting the inclination, the adhesive filled between the outer periphery of the actuator drive shaft and the inner peripheral wall of the adjustment hole is cured to hold the actuator drive shaft on the frame. The backlash between the moving lens group engaged with the frame and the frame can be eliminated, and the movement and rotation of the moving lens group due to the backlash can be suppressed. Thereby, deterioration of optical performance can be prevented. Further, it is possible to prevent dust and dirt from entering between the outer periphery of the drive shaft of the actuator and the inner peripheral wall of the adjustment hole.

  In the above embodiment, the adhesive is filled before the tip of the drive shaft 42 of the actuator 4 is swung. However, the present invention is not limited to this, and for example, the tip of the drive shaft 42 of the actuator 4 is swung. It may be filled later and can be changed as appropriate.

  Moreover, in the said embodiment, although the 2nd and 3rd group unit which has a fixed lens group is provided, it can change suitably not only in the thing of this form. For example, the fixed lens group may not be provided, or one or more units having the fixed lens group may be provided.

DESCRIPTION OF SYMBOLS 1 Imaging device 2 1st group unit 3a 2nd group unit 3b 3rd group unit 4 Actuator 5 Case 7 Sensor substrate 41 Piezoelectric element (electromechanical conversion element)
42 Drive shaft 43 Weight 51 Rear frame 52 Front frame 526 Adjustment hole

Claims (4)

An actuator having a drive shaft connected to the electromechanical conversion element and having a movable lens group engaged with a predetermined frictional force is disposed in the frame so that both ends in the axial direction of the actuator are held in the frame, and the imaging device A method of manufacturing an imaging device in which a sensor substrate having a fixed attachment to the frame is provided,
The actuator is disposed in the frame, and the sensor substrate is fixedly attached to the frame.
Thereafter, the axial tilt of the drive shaft of the actuator is adjusted with respect to the sensor substrate. The actuator is arranged in the frame so that one end can be swung with the other end arranged on the sensor substrate side in the actuator as a fulcrum,
The method of manufacturing an imaging apparatus according to claim 1, wherein the inclination is adjusted by swinging one end of the actuator. The tip of the drive shaft forms the one end,
The frame is provided with an adjustment hole into which the tip of the drive shaft is inserted,
Allowing one end of the actuator to swing by inserting the tip of the drive shaft into the adjustment hole;
After the adjustment of the inclination, the adhesive filled between the outer periphery of the tip of the drive shaft and the inner peripheral wall of the adjustment hole is cured to hold the tip of the drive shaft on the frame. The manufacturing method of the imaging device of Claim 2.   The method for manufacturing an imaging apparatus according to claim 1, wherein an inclination of a drive shaft of the actuator is adjusted based on an image signal output from the sensor substrate.

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