JP2003230028A - Small-sized module camera - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a small-sized module camera incorporating a mobile phone with a structure capable of making the height lower to attain downsizing, employing a flexible board with a thickness of about 0.3 mm to 0.4 mm, and uniquely and simply aligning a lens optical axis and a light receiving section at assembling. <P>SOLUTION: A projection 6c of a lens holder 6 is fitted to a hole of the flexible board 7 to support an upper face of the flexible board 7 with a lower face of the lens holder 6. An imaging element bear chip 5 is placed by facing an end of the projection 6c and the wiring pattern of the lower side of the flexible board 7 and the imaging element bear chip 5 are flip-chip-mounted. The light receiving section of the imaging element bear chip 5 and the optical axis of the lens are aligned with high accuracy and it is possible for integrated assembly independently of the thin thickness of the board. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a small module camera mounted on a mobile phone or the like which is required to be small and thin.

[0002]

2. Description of the Related Art Miniaturization of a camera module built into a mobile phone is required. Until now, it has been considered to reduce the size in the XY directions (plane direction). However, in the future, as the mobile phone becomes multifunctional, the camera block is required to be small, and the display unit is changed from the liquid crystal to the one using the EL element, and the thinning is required.

FIG. 4 is a sectional view for explaining the structure of a conventional module camera. One-chip image sensor 2
3 is manufactured by mounting the bare chip 31 integrally formed with the light receiving portion 22 and the DSP on the silicon substrate 25, performing the wire bonding 26 on the gold-plated land, and attaching the glass 27 on the upper surface of the bare chip 31 for packaging. . The one-chip image sensor 23 is attached to a resin substrate (ceramic substrate or the like) 29 by soldering with a ball grid array (BGA) 24.
The lens supported by the lens holder 28 is incorporated on this, and the camera module is completed.

Parts (resistors, capacitors, etc.) necessary for the camera module are attached to the back surface of the resin substrate 29. In the conventional module camera, miniaturization of chips (CSP and BGA) is progressing in the XY directions as described above. However, since the lens, the lens holder, the packaged one-chip image sensor, and the substrate are simply stacked, the height in the Z direction (thickness direction) cannot be lowered.

[0005]

As a solution to this problem, Japanese Patent Laid-Open No. 2001-203913 has been proposed. FIG. 5 is a diagram showing the structure of the proposed module camera. A lens is attached to the lens barrel 42, and a holder 43 that supports the lens barrel 42 is mounted on the translucent substrate 40. The image pickup device 41 having the light receiving portion 35 is connected to the wiring pattern 33 of the transparent substrate 40 by the bumps 36, and the image pickup device 41 is fixed by the resin 37. This structure is thinner than the conventional structure in the thickness direction. Translucent substrate 4 used in this camera module
0 is a glass material having an infrared cut function with a thickness of about 1 mm as described in the section of the detailed description of the proposed specification, and holds the assembly by the rigidity of the glass itself.

When a camera module is incorporated in a mobile phone, it is essential to use a flexible substrate (thickness is about 0.3 mm to 0.4 mm) for mounting other components at the same time. Assuming that a transparent plate having a thickness of 0.3 mm to 0.4 mm is used in the above proposal, it is impossible to make a glass having a thickness of 0.3 mm to 0.4 mm strong in the structure proposed. Is. Further, as a practical problem, if a hard substrate having a certain thickness is used to have strength, it cannot be freely bent and cannot be stored in a narrow space. Further, the optical axis position of the lens 39 and the light receiving portion 3 of the image pickup element 41.
5 is a structure to be mounted on the upper and lower surfaces of the translucent substrate, and does not have a structure for uniquely determining the position. Therefore, a measure for alignment is required, which causes a problem of complicated manufacturing process. .

The present invention solves the above-mentioned problems, and an object of the present invention is to make a camera module with a built-in mobile phone thinner in the height direction for downsizing, and 0.3 mm to
It is an object of the present invention to provide a small-sized Mojar camera having a structure in which a flexible substrate having a thickness of about 0.4 mm can be used and the alignment of the lens optical axis and the light receiving portion can be uniquely and easily made during assembly.

[0008]

In order to achieve the above object, a small module camera according to the present invention comprises a lens, a lens supporting the lens, an opening at an upper portion, and a protruding portion at a lower surface. A lens holder having a through hole in the portion, a printed circuit board having the hole, and an image sensor bare chip, and the protrusion of the lens holder is fitted into the hole of the printed circuit board so that the upper surface of the printed circuit board is the lens holder. Of the image pickup device bare chip by arranging the image pickup device bare chip so as to face the end of the protruding portion and flip-chip mounting the image pickup device bare chip and the wiring pattern on the lower surface of the printed circuit board. Align the optical axis of the lens with the optical axis of the lens, and
It can be integrally assembled regardless of the thinness of the printed circuit board. In the above-mentioned structure of the present invention, the upper surface of the printed board and the lower surface of the lens holder are fixed with an adhesive. In the above structure, the present invention is configured by filling an underfill agent between the image pickup element bare chip and the printed circuit board. The printed board in the present invention uses a flexible board.

[0009]

According to the above construction, the module can be made thinner, and the module can be accurately aligned and incorporated only in the step of integrally forming it on the printed board, and the flexible board can be integrally formed. It becomes possible to do. Therefore, when the module camera is incorporated in a mobile phone, the flexible substrate can be bent into a U-shape to be housed, and other chips can be further mounted, and at the same time, the demand for the thinness of the phone body can be met.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a perspective view showing the external appearance of a mobile phone using a small module camera according to the present invention. The small module camera 16 according to the present invention is arranged above the EL device display drawing 15 of the flip type mobile phone 17. It can be suitably accommodated in a thin lid.

FIG. 2 is a sectional view showing an embodiment of a small module camera according to the present invention. An opening 6d is provided at the center of the upper wall 6a of the lens holder 6. Lower wall 6
A protrusion 6c is formed at the center of b, and a through hole 6e is provided in the protrusion 6c. The lens 1 is attached so as to be sandwiched between the upper wall 6a and the lower wall 6b.

The flexible substrate 7 has a hole 7a in the center, and the projection 6c of the lens holder 6 is fitted into the hole 7a. Lower wall 6b of lens holder 6 of flexible substrate 7
An adhesive is applied to the portion in contact with the lower surface of the flexible substrate 7 and the lower wall 6 of the lens holder 6 by fitting into the hole.
The lower surface of b is adhesively fixed. The flexible substrate 7 is
The lower wall of the lens holder 6 holds the strength of the module.

At the tip of the protruding portion 6c, the image pickup element bare chip 5 on which the light receiving portion 2 is mounted is arranged to face the lens 1. The image pickup element bare chip 5 has a gold-plated portion (including bumps) 4 in the peripheral portion, and is flip-chip mounted by the gold-plated portion 10 that connects this portion to the pattern 7a formed on the lower surface of the flexible substrate 7. Further, an underfill agent 9 is filled in this portion and fixed. Parts such as resistors and capacitors 8 are attached to the back surface of the flexible substrate 7.

The distance between the light receiving element 2 of the image pickup element bare chip 5 and the lens is uniquely determined by the height of the protruding portion 6c (the length of the through hole 6e) and can be set at the focus position only by mounting. Further, the position adjustment of the light receiving unit 2 and the optical axis is performed by
Since it suffices to perform it on the lens holder without passing through the glass, alignment is easy. That is, since the lens mounting position with respect to the substrate is uniquely determined, the gold-plated portion 4 on the peripheral portion of the image pickup device bare chip 5 and the gold-plated portion 10 on the pattern on the back surface of the flexible substrate 7 do not significantly deviate, so that the adjustment amount is The number is small and the alignment can be done easily.

FIG. 3 is a diagram showing an example of mounting the small module camera shown in FIG. Module camera 1 according to the present invention
The flexible board 12 on which the 3 is mounted is folded in two, and the IC bare chip 11 is placed at a position facing the bent portion.
And resistors and capacitors are installed. By folding in half in this way, it can be built in a thin and small mobile phone.

The embodiment of the flexible substrate having a thickness of 0.3 mm to 0.4 mm has been described above, but it may be thinner than this. On the other hand, if it is thicker than this, it becomes difficult to deform, but it is also possible to use a rigid (resin, ceramic, etc.) substrate.

[0017]

As described above, according to the present invention, the projecting portion of the lens holder is fitted into the hole of the printed circuit board so that the upper surface of the printed circuit board is supported by the lower surface of the lens holder and the end portion of the projecting portion is supported. By arranging the image sensor bare chip so as to face each other and flip-chip mounting the image sensor bare chip and the wiring pattern on the lower surface of the printed circuit board, the light receiving part of the image sensor bare chip and the optical axis of the lens are accurately aligned, and the printed circuit board It is configured so that it can be integrally assembled regardless of its thinness. Therefore, the camera module can be formed even if the substrate is thin and thin and can be bent in a U shape like a flexible substrate. Therefore, a module using a flexible substrate can be assembled in a mobile phone or the like, and further miniaturization and thinning of the mobile phone can be promoted. Further, the adjustment of the alignment at the time of assembly becomes easy, and the manufacturing process is simplified.

[Brief description of drawings]

FIG. 1 is a perspective view showing an appearance of a mobile phone using a small module camera according to the present invention.

FIG. 2 is a sectional view showing an embodiment of a small module camera according to the present invention.

FIG. 3 is a diagram showing an example of mounting the small module camera shown in FIG.

FIG. 4 is a sectional view for explaining the structure of a conventional module camera.

FIG. 5 is a sectional view showing another example of a conventional module camera.

[Explanation of symbols]

1 lens 2,35 Light receiving part 4,36 Gold plated part (including bump) 5 Image sensor bare chip 6,28 Lens holder 7 Flexible substrate 8 and 30 resistors and capacitors 9 Underfill agent 10 Gold plated 11 IC bare chip 15 EL element display screen 16 small module camera 17 mobile phones 23 One-chip image sensor 24 BGA (solder) 25 Silicon substrate 26 Wire bonding 27 glass 29 Resin substrate 31 bare chip 32 gold plating 33 wiring pattern 37 resin 38 lens unit 40 translucent substrate 41 Image sensor 42 lens barrel 43 holder

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) G03B 17/02 G03B 17/02 H04M 1/02 H04M 1/02 C H04N 5/335 H04N 5/335 V F Terms (reference) 2H044 AA04 AA14 AC01 AE06 AJ04 AJ06 AJ07 2H100 AA31 BB11 5C022 AA11 AC42 AC70 AC78 5C024 CY48 EX22 EX25 5K023 AA07 BB03 BB04 DD08 LL01 MM00 MM25

Claims (4)

[Claims] 1. A lens, a lens holder that supports the lens, has an opening in an upper portion, has a protrusion on a lower surface, and has a through hole in the protrusion, a printed circuit board having a hole, and an image sensor. A bare chip, the projection of the lens holder is fitted into the hole of the printed circuit board, the upper surface of the printed circuit board is supported by the lower surface of the lens holder, and the imaging element is faced to the end of the projecting section. By disposing a bare chip and mounting the image pickup device bare chip and the wiring pattern on the lower surface of the printed circuit board by flip chip mounting, the light receiving part of the image pickup device bare chip and the optical axis of the lens are accurately aligned, and the thinness of the printed circuit board is improved. A compact module camera characterized by being configured so that it can be assembled together regardless of size. 2. The small module camera according to claim 1, wherein an upper surface of the printed board and a lower surface of the lens holder are fixed with an adhesive. 3. The small module camera according to claim 1, wherein an underfill agent is filled between the image pickup element bare chip and the printed circuit board. 4. The small module camera according to claim 1, wherein the printed circuit board is a flexible circuit board.