JP5983971B2 - Manufacturing method of camera module - Google Patents

Description

  The present invention relates to a method for manufacturing a camera module, and more particularly to a method for manufacturing an autofocus camera module used for a portable small camera.

  A portable small camera is mounted on a camera-equipped mobile phone. This portable small camera uses an autofocus camera module. Conventionally, various autofocus camera modules have been proposed.

  For example, Patent Document 1 (Japanese Patent Laid-Open No. 2006-258969) discloses a camera-equipped mobile phone in which the time required for autofocus is reduced. The camera-equipped mobile phone (camera module) disclosed in Patent Document 1 includes an actuator (lens driving device) that supports a lens (lens assembly, lens barrel) so as to be movable along the optical axis direction of the lens, and an image pickup device. It comprises a sensor substrate on which elements and electronic components are mounted, and a sealing member provided between the actuator and the sensor substrate. The sealing member is combined with the sensor substrate to form a sealed space that seals the imaging element and the electronic component. The actuator includes an actuator body and an actuator base. The sealing member is also called a sensor base. That is, the conventional camera module is composed of four members (parts) of an actuator body, an actuator base, a sensor base, and a sensor substrate.

  The actuator body disclosed in Patent Document 1 includes a holder (lens holder) having a cylindrical portion with a lens (lens assembly, lens barrel) attached to one end thereof, and the holder (lens holder) includes a cylindrical portion of the holder. A holder (lens holder) provided on both sides in the optical axis direction of a cylindrical portion of a drive coil fixed so as to be positioned around, a yoke having a permanent magnet facing the drive coil, and a holder (lens holder) And a pair of leaf springs that are supported so as to be displaceable in the optical axis direction. By energizing the drive coil, the position of the lens (lens assembly) can be adjusted in the optical axis direction by the interaction between the magnetic field of the permanent magnet and the magnetic field generated by the current flowing in the drive coil. One of the pair of leaf springs is called an upper leaf spring (front spring), and the other is called a lower leaf spring (rear spring). The inner peripheral side end of the upper leaf spring (front spring) is sandwiched between the upper end (front end) of the holder and the stopper and is fitted to the holder (lens holder).

  Hereinafter, a conventional camera module 40 according to the prior art will be described in detail with reference to FIGS. 1 and 2. 1 and 2 are exploded sectional views of a conventional camera module 40. Here, as shown in FIGS. 1 and 2, an orthogonal coordinate system (X, Y, Z) is used. In the state shown in FIGS. 1 and 2, in the Cartesian coordinate system (X, Y, Z), the X axis is the front-rear direction (depth direction), the Y axis is the left-right direction (width direction), and the Z axis is The vertical direction (height direction). In the example shown in FIGS. 1 and 2, the vertical direction Z is the direction of the optical axis O of the lens.

  However, in the actual use situation, the optical axis O direction, that is, the Z-axis direction is the front-rear direction. In other words, the upward direction of the Z axis is the forward direction, and the downward direction of the Z axis is the backward direction.

  As shown in FIG. 1, the camera module 40 includes an actuator (lens driving device) 10 that supports the lens assembly 15 so as to be movable along the optical axis O direction of the lens, an image sensor 421, and electronic components (not shown). 2) and a sensor base 44 provided between the actuator 10 and the sensor substrate 42. An IR cut filter 441 is mounted on the sensor base 44.

  As shown in FIG. 2, the actuator 10 includes an actuator body 11 and an actuator base 12. Thus, the conventional camera module 40 is composed of four members (parts), that is, the actuator body 11, the actuator base 12, the sensor base 44, and the sensor substrate 42.

  The illustrated actuator (lens driving device) 10 is provided in a camera-equipped mobile phone capable of autofocusing. The actuator (lens driving device) 10 is for moving the lens assembly 15 in the direction of the optical axis O. The actuator (lens driving device) 10 has an actuator base 12 disposed on the lower side (rear side) in the Z-axis direction (optical axis O direction). On the lower part (rear part) of the actuator base 12, an image sensor 421 disposed on the sensor substrate 42 is mounted. The image sensor 421 captures the subject image formed by the lens assembly 15 and converts it into an electrical signal. The image sensor 421 is configured by, for example, a CCD (charge coupled device) type image sensor, a CMOS (complementary metal oxide semiconductor) type image sensor, or the like. Therefore, the camera module 40 is configured by a combination of the actuator (lens driving device) 10, the sensor substrate 42 on which the image sensor 421 is mounted, and the sensor base 44.

  The actuator (lens driving device) 10 includes a lens holder 14 having a cylindrical portion 140 for holding the lens assembly 15, and a driving coil 16 fixed to the lens holder 14 so as to be positioned around the cylindrical portion 140. And a yoke 20 having a permanent magnet 18 facing the drive coil 16 and a pair of leaf springs 22 and 24 provided on both sides of the cylindrical portion 140 of the lens holder 14 in the optical axis O direction. The pair of leaf springs 22 and 24 support the lens holder 14 so as to be displaceable in the optical axis O direction with the lens holder 14 positioned in the radial direction. Of the pair of leaf springs 22, 24, one leaf spring 22 is called an upper leaf spring, and the other leaf spring 24 is called a lower leaf spring.

  Further, as described above, in the actual use situation, the upward direction in the Z-axis direction (optical axis O direction) is the forward direction, and the downward direction in the Z-axis direction (optical axis O direction) is the backward direction. Therefore, the upper leaf spring 22 is also called a front spring, and the lower leaf spring 24 is also called a rear spring.

  A permanent magnet 18 is disposed on the inner peripheral surface of the outer cylindrical portion 202 of the yoke 20 at a distance from the drive coil 16.

  The upper leaf spring (front spring) 22 is disposed on the upper side (front side) of the lens holder 14 in the optical axis O direction, and the lower leaf spring (rear side spring) 24 is disposed on the lower side (rear side) of the lens holder 14 in the optical axis O direction. Be placed. The upper leaf spring (front spring) 22 and the lower leaf spring (rear spring) 24 have substantially the same configuration.

  That is, the upper leaf spring (front spring) 22 has an inner peripheral end 222 attached to the lens holder 14 and an outer peripheral end 224 attached to the yoke 20. Three arms are provided between the inner peripheral end 222 and the outer peripheral end 224. Each arm portion connects the inner peripheral end 222 and the outer peripheral end 224.

  Similarly, the lower leaf spring (rear spring) 24 has an inner peripheral end 242 attached to the lens holder 14 and an outer peripheral end 244 attached to the yoke 20. Three arms are provided between the inner peripheral end 242 and the outer peripheral end 244. Each arm portion connects the inner peripheral side end 242 and the outer peripheral side end 244.

  The inner peripheral end is also called an inner ring, and the outer peripheral end is also called an outer ring.

  An inner peripheral end 222 of the upper leaf spring (front spring) 22 is sandwiched and fixed between the lens holder 14 and the stopper 26. In other words, the stopper 26 is fitted to the lens holder 14 so as to sandwich the inner peripheral end 222 of the upper leaf spring (front spring) 22 with the lens holder 14. On the other hand, the outer peripheral side end 224 of the upper leaf spring (front spring) 22 is sandwiched and fixed between the yoke 20 and the cover 28.

  The stopper 26 has the following functions. That is, the stopper 26 has a function of closely contacting the inner peripheral end 222 of the upper leaf spring (front spring) 22 to the lens holder 14 with high accuracy. As a result, variations in VCM (voice coil motor) characteristics can be improved. The stopper 26 has a function of improving the adhesive strength of the upper leaf spring (front spring) 22. Thereby, the impact resistance of the lens driving device 10 is improved. Further, the stopper 26 has a function of preventing deformation of the upper leaf spring (front spring) 22 when the lens driving device 10 is dropped. This also improves the impact resistance of the lens driving device 10. The stopper 26 has a function of determining the mechanical stroke of the lens driving device 10.

  On the other hand, an outer peripheral end 244 of the lower leaf spring (rear spring) 24 is fixed to the yoke 20 via a spacer 30. In other words, the spacer 30 and the outer end 244 of the lower leaf spring (rear spring) 24 are sandwiched and fixed between the yoke 20 and the actuator base 12. An inner peripheral end 242 of the lower leaf spring (rear spring) 24 is fixed to the lower end (rear end) side of the lens holder 14.

  A female screw (not shown) is cut on the inner peripheral wall of the cylindrical portion 140 of the lens holder 14. On the other hand, a male screw (not shown) screwed into the female screw is cut on the outer peripheral wall of the lens assembly 15. Therefore, in order to attach the lens assembly 15 to the lens holder 14, the lens assembly 15 is rotated around the optical axis O with respect to the cylindrical portion 140 of the lens holder 14 and screwed along the optical axis O direction. The lens assembly 15 is accommodated in the lens holder 14 and bonded to each other with an adhesive.

  By energizing the drive coil 16, it is possible to adjust the position of the lens holder 14 (lens assembly 15) in the direction of the optical axis O by the interaction between the magnetic field of the permanent magnet 18 and the magnetic field generated by the current flowing through the drive coil 16. is there.

  A sheet-like electrode 32 is arranged between the lower leaf spring (rear spring) 24 and the base 12. The sheet-like electrode 32 is for supplying power to the drive coil 16.

  An annular convex portion 122 is provided on the bottom surface of the actuator base 12. On the other hand, an annular recess 442 is provided on the upper surface of the sensor base 44 at a position corresponding to the annular projection 122. The annular convex portion 122 and the annular concave portion 442 are for preventing intrusion of dust and light incidence.

  Next, a method for manufacturing the conventional camera module 40 shown in FIGS. 1 and 2 will be described.

  First, the IR cut filter 441 is attached to the sensor base 44. At this time, a thermosetting adhesive resin is applied and the resin is cured by thermal bonding. Next, the sensor base 44 is attached to the sensor substrate 42. At this time, a thermosetting adhesive resin is applied and the resin is cured by thermal bonding. Thereby, a sensor part is manufactured. A protective tape is affixed to the sensor parts (42, 44) thus manufactured, and the sensor parts (42, 44) are temporarily stored.

  Subsequently, the protective tape is peeled off, and the actuator 10 is attached to the sensor portions (42, 44). At this time, XY adjustment is performed, UV resin is applied, and the UV resin is temporarily cured to temporarily fix it. Next, a thermosetting adhesive resin is applied and the resin is cured by thermal bonding. In this way, the camera module 40 is manufactured.

Japanese Patent Laying-Open No. 2006-258969 (FIGS. 2, 3, and 4)

  The conventional camera module 40 illustrated in FIGS. 1 and 2 as disclosed in Patent Document 1 has the following problems.

  The first problem is that it is difficult to assemble the camera module 40 with high positional accuracy. The reason is that the conventional camera module 40 is composed of four members (parts) of the actuator main body 11, the actuator base 12, the sensor base 44, and the sensor substrate 42. More specifically, when the actuator base 12 is attached to the actuator body 11, a positional variation of ± 20 μm occurs. Further, when the sensor base 44 is attached to the sensor substrate 42, a positional variation of ± 20 μm occurs. Further, when the actuator 10 is attached to the sensor portions (42, 44) while adjusting the XY, a positional variation of ± 20 μm occurs. Therefore, since a total position variation of ± 60 μm occurs, it becomes difficult to position and assemble the camera module 40 with high accuracy.

  The second problem is that the cost of the camera module 40 increases. The reason is that in order to combine the actuator base 12 and the sensor base 44, it is necessary to provide the annular convex portion 122 and the annular concave portion 442 for preventing dust intrusion and light incidence as described above. .

  A third problem is that it is difficult to reduce the height of the camera module 40. The reason is that the conventional camera module 40 is composed of four members (components), that is, an actuator body 11, an actuator base 12, a sensor base 44, and a sensor substrate 42. This is because the height is increased with the thickness of).

  Therefore, the subject of this invention is providing the manufacturing method of the camera module which can be assembled with sufficient position accuracy.

  Another object of the present invention is to provide a camera module manufacturing method that can be manufactured at low cost.

  Still another object of the present invention is to provide a method of manufacturing a camera module capable of reducing the height.

  Other objects of the invention will become apparent as the description proceeds.

According to the aspect of the present invention, the lens holder (14) including the cylindrical portion (140) for holding the lens assembly (15) is included, and the lens holder (14) is attached to the leaf springs (22, 24). The actuator main body (11) that is displaced in the optical axis direction (O) while being positioned in the radial direction using ; the sensor substrate (42) on which the imaging element (421) is mounted; the actuator main body (11) and the sensor substrate ( 42) and a base member (60) composed of a single member serving as an actuator base (12) and a sensor base (44), and a camera module (40A) comprising The actuator body (11) and the base member (60) are combined with an IR cut filter (441) mounted on the base member (60). Thus, a method of manufacturing the camera module (40A) is provided, which includes a step of configuring the actuator portion (11, 60) and a step of attaching the actuator portion (11, 60) to the sensor substrate (42). .

The manufacturing method of the camera module (40A) includes a sensor substrate (42) and a base member (60), and positioning members (425, 65) provided on both the sensor substrate (42) and the base member (60). It is preferable to further include a step of using and positioning. The positioning member includes, for example, a plurality of positioning recesses (425) provided on the sensor substrate (42) and a plurality of positioning protrusions provided on the base member (60) at positions corresponding to the plurality of positioning recesses. Part (65). It is desirable that the sensor substrate (42) and the base member (60) have a rectangular shape having substantially the same vertical and horizontal dimensions. In this case, the plurality of positioning recesses (425) may be provided at the four corners of the sensor substrate (42), and the plurality of positioning protrusions (65) may be provided at the four corners of the base member (60).

  The reference numerals in the parentheses are given for ease of understanding, and are merely examples, and of course are not limited thereto.

  In the present invention, the actuator main body and the base member are mounted on the sensor board after the IR cut filter is mounted on the base member and combined to form the actuator portion. It can be manufactured at low cost and can be reduced in height.

It is a disassembled sectional view of the conventional camera module. It is a disassembled sectional view of the conventional camera module. FIG. 10 is an exploded cross-sectional view showing a conventional camera module showing a state in which a shield film deposition process for making a shield common is performed on an actuator base and a sensor base. It is an exploded sectional view showing the conventional camera module which shows the state where conductive resin is used between the actuator base and the sensor base. 1 is an exploded cross-sectional view of a camera module according to an embodiment of the present invention. FIG. 6 is an exploded cross-sectional view of the camera module shown in FIG. 5 showing a state in which a shield film deposition process is performed to shield the base member. It is sectional drawing which compared and showed the back of the conventional camera module and the camera module which concerns on embodiment of this invention. 6A and 6B are diagrams showing a sensor substrate used in the camera module shown in FIG. 5, wherein FIG. 6A is a plan view of the sensor substrate, and FIG. 6B is a front view of the sensor substrate. It is a figure which shows the base member used for the camera module shown in FIG. 5, (A) is a front view of a base member, (B) is a bottom view of a base member. It is a figure which shows the state which positions by combining an actuator part and a sensor board | substrate, (A) is an exploded front view before assembling a camera module, (B) is a front view after assembling a camera module.

  Embodiments of the present invention will be described below with reference to the drawings.

  With reference to FIG. 5, the manufacturing method of the camera module 40A by one Embodiment of this invention is demonstrated. FIG. 5 is an exploded sectional view of the camera module 40A. Here, as shown in FIG. 5, an orthogonal coordinate system (X, Y, Z) is used. In the state illustrated in FIG. 5, in the orthogonal coordinate system (X, Y, Z), the X axis is the front-rear direction (depth direction), the Y axis is the left-right direction (width direction), and the Z axis is the vertical direction ( Height direction). In the example shown in FIG. 5, the vertical direction Z is the direction of the optical axis O of the lens.

  However, in the actual use situation, the optical axis O direction, that is, the Z-axis direction is the front-rear direction. In other words, the upward direction of the Z axis is the forward direction, and the downward direction of the Z axis is the backward direction.

  The illustrated camera module 40A has the same configuration as the conventional camera module 40 shown in FIGS. 1 to 4 except that a base member 60 is used instead of the actuator base 12 and the sensor base 44. Have Therefore, the same components as those shown in FIGS. 1 to 4 are denoted by the same reference numerals, and only different points will be described below for the sake of simplicity.

  The base member 60 is disposed between the actuator body 11 and the sensor substrate 42. The base member 60 is composed of one member that serves as the actuator base 12 and the sensor base 44 in the conventional camera module 40. The base member 60 is equipped with an IR cut filter 441.

  That is, the camera module 40 </ b> A according to the present embodiment includes three members (parts), that is, the actuator body 11, the base member 60, and the sensor substrate 42. In the manufacturing method of the camera module 40A according to the present embodiment, the actuator body 11 and the base member 60 are mounted on the base member 60 with the IR cut filter 441 and combined to form the actuator portion (11, 60). The actuator parts (11, 60) are attached to the sensor substrate.

  Next, a method for manufacturing the camera module 40A shown in FIG. 5 will be described.

  First, the IR cut filter 441 is attached to the base member 60. At this time, a thermosetting adhesive resin is applied and the resin is cured by thermal bonding. Next, the actuator body (11, 60) is configured by combining the actuator body 11 and the base member 60. Then, the actuator unit (11, 60) is attached to the sensor substrate 42. At this time, a thermosetting adhesive resin is applied and the resin is cured by thermal bonding. In this way, the camera module 40A is manufactured.

  The manufacturing method of the camera module 40A having such a configuration has the following advantages.

  The first advantage is that the camera module 40A can be assembled with high positional accuracy. The reason is that the camera module 40A is composed of three members (parts): the actuator body 11, the base member 60 on which the IR cut filter 441 is mounted, and the sensor substrate 42. The actuator body 11 and the IR cut filter 441 This is because the actuator portion (11, 60) composed of a combination with the base member 60 on which the sensor board is mounted is attached to the sensor substrate. More specifically, when the base member 60 is attached to the actuator body 11, a positional variation of ± 20 μm occurs. Further, when the actuator portions (11, 60) are attached to the sensor substrate 42, a positional variation of ± 20 μm occurs. Therefore, it is possible to suppress the positional variation of ± 40 μm in total. That is, no adjustment is possible. Thereby, the camera module 40A can be positioned and assembled with high accuracy.

  A second advantage is that the cost of the camera module 40A can be reduced. The reason is that the base member 60 integrated with the conventional actuator base 12 and the sensor base 44 is used, so that an annular protrusion for preventing dust intrusion and light incidence is required in the conventional camera module 40. This is because it is not necessary to provide the portion 122 and the annular recess 442. Moreover, in order to shield the base member 60 which is one member, a shield film deposition process may be performed. FIG. 6 shows a shield film 63 applied to the base member 60 by vapor deposition. That is, the shield film 63 is deposited on the outer peripheral side surface of the base member 60. Therefore, it is only necessary to perform shield film deposition processing on only one component. Furthermore, it is not necessary to use the conductive resin 52 (FIG. 4) between the actuator base 12 and the sensor base 44 as in the conventional camera module 40.

  A third advantage is that the camera module 40A can be reduced in height. The reason is that the camera module 40A is composed of three members (components), that is, the actuator body 11, the base member 60 on which the IR cut filter 441 is mounted, and the sensor substrate 42. This is because the height can be lowered even if the thickness is increased.

  FIG. 7A shows a cross-sectional view of a conventional camera module 40, and FIG. 7B shows a cross-sectional view of a camera module 40A according to the present embodiment.

  As is clear by comparing FIG. 7A and FIG. 7B, the camera module 40A according to the present embodiment is shorter than the conventional camera module 40 by a height H. I understand that.

  This is because the actuator base 12 and the sensor base 44 are made into one base member 60, so that there is a margin for the strength of parts (members) and the limit dimensions that can be manufactured, and as a result, the degree of freedom in part design increases. This is because the total height of the parts can be reduced.

  Next, positioning between the sensor substrate 42 and the base member 60 in the camera module 40A according to the present embodiment will be described with reference to FIGS.

  8A and 8B are diagrams showing the sensor substrate 42. FIG. 8A is a plan view of the sensor substrate 42, and FIG. 8B is a front view of the sensor substrate 42. FIG. 9A and 9B are views showing the base member 60, where FIG. 9A is a front view of the base member 60, and FIG. 9B is a bottom view of the base member 60. FIG. 10A and 10B are views showing a state in which the actuator unit (11, 60) and the sensor substrate 42 are combined for positioning. FIG. 10A is an exploded front view before assembling the camera module 40A, and FIG. 10B is a camera module 40A. It is a front view after assembling.

  As shown in FIGS. 8 and 9, the sensor substrate 42 and the base member 60 have rectangular shapes having substantially the same vertical and horizontal dimensions. The sensor substrate 42 has four positioning recesses 425 provided at the four corners thereof. On the other hand, the base member 60 has four positioning convex portions 65 provided at the four corners thereof. That is, the four positioning convex portions 65 are provided at positions corresponding to the four positioning concave portions 425, respectively. The combination of the four positioning concave portions 425 and the four positioning convex portions 65 serves as a positioning member for positioning the sensor substrate 42 and the base member 60.

  Therefore, as shown in FIG. 10, by combining (fitting) the four positioning convex portions 65 of the base member 60 and the four positioning concave portions 425 of the sensor substrate 42, the actuator portion (11, 60) and the sensor substrate 42 can be positioned.

  In the above embodiment, the sensor substrate 42 is provided with a plurality of positioning concave portions 425 and the base member 60 is provided with four positioning convex portions 65, but conversely, the sensor substrate has a plurality of positioning convex portions. And four positioning recesses may be provided in the base member 60.

  Although the present invention has been described with reference to preferred embodiments, it is obvious that various modifications can be made by those skilled in the art without departing from the spirit of the present invention. For example, the actuator body that supports the lens assembly so as to be movable along the optical axis direction of the lens is not limited to that of the above-described embodiment, and may have various configurations.

10 Actuator (Lens Drive Device)
DESCRIPTION OF SYMBOLS 11 Actuator main body 14 Lens holder 140 Cylindrical part 16 Drive coil 18 Permanent magnet 20 Yoke 22 Upper leaf | plate spring (front side spring)
222 Inner peripheral edge (inner ring)
224 Outer end (outer ring)
24 Lower leaf spring (rear spring)
242 Inner peripheral edge (inner ring)
244 Outer end (outer ring)
26 Stopper 32 Sheet Electrode 40A Lens Module 42 Sensor Board 421 Image Sensor 425 Positioning Concave 441 IR Cut Filter 60 Base Member 65 Positioning Convex

Claims (4)

An actuator body including a lens holder having a cylindrical portion for holding a lens assembly, the lens holder being displaced in a radial direction using a leaf spring, and being displaced in an optical axis direction;
A sensor board on which an image sensor is mounted;
A base member that is disposed between the actuator main body and the sensor substrate and is configured by a single member that serves as an actuator base and a sensor base;
A method for manufacturing a camera module comprising:
The actuator body and the base member are mounted with an IR cut filter on the base member and combined to form an actuator portion;
Attaching the actuator part to the sensor substrate;
A method for manufacturing a camera module. The method of manufacturing a camera module according to claim 1, further comprising a step of positioning the sensor substrate and the base member using positioning members provided on both the sensor substrate and the base member . The positioning member is
A plurality of positioning recesses provided on the sensor substrate;
A plurality of positioning convex portions provided on the base member at positions corresponding to the plurality of positioning concave portions;
The manufacturing method of the camera module of Claim 2 comprised from these. The sensor substrate and the base member have a rectangular shape with substantially the same vertical and horizontal dimensions,
The plurality of positioning recesses are provided at four corners of the sensor substrate,
The plurality of positioning convex portions are provided at four corners of the base member,
The manufacturing method of the camera module of Claim 3.

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