JP2002016826A - Mounting structure of imaging device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To sharply reduce the dimension (thickness) of depth while securing the interval between the light receiving part of a CCD imaging device and a lens. SOLUTION: This is a mounting structure where an imaging device is mounted directly on a lens tube equipped with a lens for image pickup. Or, a lens tube is mounted with a lens for image pickup on one side of a circuit board, also an opening in the circuit board is formed corresponding to the lens tube, and an imaging device is mounted so that a light receiving part may face the opening on the other side of the circuit board. In either case, the interval between the light receiving part of the CCD imaging device and the lens is secured, and also the dimension of depth (thickness) is sharply reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mounting structure of an image pickup device for realizing, for example, a very small digital still camera.

[0002]

2. Description of the Related Art In recent years, so-called digital still cameras, which convert captured images into digital signals and record them in memory devices or the like, instead of ordinary cameras using a silver halide film, have become widespread.

[0003] Images taken with a digital still camera are:
There is no need for development, for example, by taking in a personal computer and outputting it to a printer, a printed matter can be easily and quickly made.

In the digital still camera, while the number of pixels of the CCD, which is an image pickup device, has been increased, it has been an issue to cope with various uses.

[0005] As one of measures to cope with various uses of the digital still camera, realization of an unprecedented ultra-small and highly portable digital still camera is mentioned.

[0006]

However, in the case where the digital still camera is to be miniaturized, various problems emerge.

For example, a digital still camera of this type is usually equipped with a lens and an image sensor for photographing. At this time, simply arranging these imaging elements and lens barrels on the circuit board increases the depth dimension, which hinders miniaturization.

FIG. 14 shows a mounting structure of a normal CCD image pickup device. A CCD image pickup device 103 is mounted in a package state on a circuit board 102 on which various circuit components 101 are mounted. The lens 10
4 is attached.

When such a mounting structure is adopted, CC
It is necessary to maintain a constant optical distance between the light receiving unit of the D image sensor 103 and the lens 104, and as a result, the lens barrel 105 projects out to one side of the circuit board 102, and is mounted on a digital still camera. In this case, the dimension in the thickness direction becomes large.

The present invention has been proposed in view of the above-mentioned problems, and is an entirely new technique capable of greatly reducing the depth (thickness) dimension while securing the distance between the light receiving section of the CCD image sensor and the lens. It is intended to provide a simple mounting structure.

It is another object of the present invention to realize an ultra-small digital still camera.

[0012]

In order to achieve the above object, a mounting structure of an image pickup device according to the present invention is characterized in that the image pickup device is directly mounted on a lens barrel having an image pickup lens. It is assumed that.

[0013] Alternatively, a lens barrel having an imaging lens is mounted on one surface of the circuit board, and an opening is formed in the circuit board corresponding to the lens barrel. The image pickup device is mounted on the surface of the device such that the light receiving portion faces the opening.

By adopting the above mounting structure, CC
At the same time that the distance between the light receiving section of the D image sensor and the lens is ensured, the depth (thickness) dimension is greatly reduced.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The mounting structure of an image sensor to which the present invention is applied will be described below in detail with reference to the drawings.

Prior to the description of the mounting structure, an ultra-small digital still camera to which the structure is applied will be described first.

This digital still camera is, for example, shown in FIG.
And has a significant feature in that it has achieved an unprecedented miniaturization (memory card size).

More specifically, the outer dimensions of the casing 1 for determining the size are about 20 mm × 60 mm × 10 mm.

The basic structure is the same as that of a normal digital still camera, and a lens unit 2 is provided at one end of a housing 1.
A shutter button 3 and a power switch 4 are arranged on one side 1a of the long side. Therefore, the digital still camera of this example has a so-called horizontal configuration, and it is natural to hold the long side horizontally and the short side vertically during shooting. The invention is not limited to this. For example, a vertical configuration may be used, in which case, the shutter button may be arranged on one side of the short side,
It will be located in front of or behind the camera.

A battery unit (not shown) serving as a power supply is housed at a position on the back side of the housing 1.
For the battery part, it is preferable to use a secondary battery having a high energy density such as a lithium ion battery,
Thereby, the space occupied by the battery unit can be suppressed. In particular, a so-called lithium ion polymer battery using a gel electrolyte or a solid electrolyte as the electrolyte is preferable.

A display unit 5 is provided on the back side of the housing 1 so that an image projected through the lens unit 2 is displayed, and the photographing screen can be visually recognized.

Here, the lens unit 2 may be a single focus lens or a type of focusing by turning a focus ring. Also, the lens unit 2
A CCD image sensor is arranged behind the
The image is converted into a digital signal in the D image sensor and the chipset.

The display unit 5 is, for example, a liquid crystal display element, and its size is very small, for example, 0.5.
It is about 5 inches.

Images photographed by the digital still camera are recorded in a memory element called a memory card.

As shown in FIG. 2, the memory element 6 has a slit-shaped insertion port 1 provided on one short side of the housing 1.
It is attached to and detached from the body from b.

The length of the short side of the housing 1 is
(The width of the memory element 6 + the thickness of both sides of the housing 1), and as a result, the size of the memory card is achieved. Normally, the connector portion of the memory element 6 in the digital still camera is formed separately from the housing 1 and is designed in a socket shape that covers the periphery (four surfaces) of the memory element 6. The three surfaces are supported by the inner surface of the housing 1 to prevent an increase in external dimensions due to the double structure of the connector portion and the housing.

When reproducing the recorded image, the recorded image is displayed on a display unit (LCD) 5 provided on the back side of the housing 1 or the memory element 6 is detached from the digital still camera main body. Play with etc.

In the digital still camera configured as described above, when the CCD image pickup device is mounted on a circuit board and the lens barrel of the lens unit 2 is mounted thereon, the depth dimension becomes large, and the size of the digital still camera becomes small. Disadvantageous in that.

Therefore, in the present invention, the above-described increase in the depth is prevented by devising the CCD image sensor directly on the rear surface of the lens barrel of the lens unit 2 and disposing the CCD image sensor through the circuit board. .

For example, the mounting structure shown in FIG. 3 is an example in which a bare chip 12 of a CCD image pickup device is directly mounted on a lens barrel 11 and penetrated through a circuit board 13.

The lens barrel 11 is a lens 1 for photographing.
The CCD imaging device needs to be disposed at a certain distance from the lens 14.

Therefore, in this embodiment, the bare chip 12 of the CCD image pickup device is connected to the rear end surface 11 of the lens barrel 11.
a. Therefore, the distance between the lens 13 and the bare chip 12 is determined by the length of the lens barrel 11.

The lens barrel 11 is mounted on the circuit board 1.
3, the entire thickness is also determined by the length of the lens barrel 11, and the lens barrel 11 can be designed with the lens barrel 11 lowered without further enlargement. As a result, the thickness dimension of the set (digital still camera) itself can be minimized.

Further, on the peripheral surface of the lens barrel 11,
A wiring pattern 15 is formed on the circuit board 1.
The third through hole 13a is connected to a connection pattern 16 formed in the form of through-hole plating by soldering or the like. Here, the connection pattern 16 is connected to the circuit board 1.
3 and is electrically connected to a so-called chip set constituted by various chip components 17 and the like.

As a result, the bare chip 12 is electrically connected to the chip set on the circuit board 13 and performs image processing of a captured image.

Next, the lens barrel 1 of the bare chip 12
1 will be described in detail.

First, a lens barrel 11 as shown in FIG. 4 is prepared. As a material of the lens barrel 11, for example, a material such as a liquid crystal polymer which does not easily cause mist is preferable.

A thread for attaching a lens to be described later is cut on the inner peripheral surface on the distal end side of the lens barrel 11, and a wiring pattern 15 is formed on the outer peripheral surface in advance.

The wiring pattern 15 is formed by connecting the lens barrel 11 to a three-dimensional molded circuit component (MID: Molded Interconn.).
ect Device) can be integrally formed. MID is a component in which electrodes (circuits) are formed on the surface of an injection molded body by a method such as electroless plating.
It is possible to form a composite part having mechanical and electrical functions by integrating the function as a circuit into the lens barrel 11.

On the other hand, the bare chip 12 of the CCD image pickup device
Has a light receiving portion 12a and a connection pad 12b as shown in FIG. 5, but a bump 18 is formed on the pad 12b in advance as shown in FIG.

The bumps 18 can be formed by any material and method such as Au studs and Ni plating.

Next, as shown in FIG.
2 and the wiring pattern 15 of the lens barrel 11 are connected to each other, and the bare chip 12 is attached to the lens barrel 11.
Is mounted, and the joint between the bump 18 and the wiring pattern 15 is sealed with resin.

The resin sealing is performed for the purpose of preventing mist from entering and preventing light from entering, and also for improving the reliability of mounting the bare chip 12.

As described above, the lens barrel 11 on which the bare chip 12 is mounted is attached to the circuit board 13.

At this time, as shown in FIG.
3, a through hole 13a corresponding to the size of the lens barrel 11 is formed in advance, and a connection pattern 16 is formed in the through hole 13a in the form of through-hole plating.

On the connection pattern 16, cream solder 19 and the like are placed, and as shown in FIG. 9, after the lens barrel 11 is mounted through the circuit board 13, wiring is performed by a method such as reflow. Pattern 15 and connection pattern 16
Solder in between.

The above series of operations is preferably performed in a clean room for the purpose of preventing mist from entering.

Finally, as shown in FIG.
By attaching a lens, an optical filter and the like to the lens barrel 11, a lens function barrel is completed.

By adopting such a configuration, the amount of protrusion of the lens barrel 11 from the circuit board 13 can be suppressed, and the height can be designed to be approximately the length of the lens barrel 11. In addition, the position of the lens barrel 11 can be arbitrarily changed in accordance with the arrangement of components, and the design of the digital still camera can be made flexible.

In the above configuration, for example, the shape of the lens barrel 11 is not limited to a straight shape as in the above example. As shown in FIG. 11, the lens side (tip side)
It is also possible to have a T-shaped cross section in which the diameter becomes thicker, or, as shown in FIG. By adopting these shapes, the contact area with the circuit board 13 can be increased,
It is possible to stabilize the mounting state.

Further, as shown in FIG.
Lens barrel 11 on the surface side with through hole 13a provided in
The bare chip 12 may be mounted on the back side.

In this case, the height dimension cannot be reduced as much as the previous example, but the height dimension can be suppressed to some extent as compared with the conventional one. Also, when the mounting of the bare chip 12 is considered, there is an advantage in that the mounting technology can be easily adopted since a normal mounting technology on a substrate can be employed and wiring to the lens barrel 11 is unnecessary.

[0053]

As is clear from the above description, by adopting the mounting structure of the present invention, the depth (thickness) can be ensured while securing the distance between the light receiving portion of the CCD image sensor and the lens.
The dimensions can be significantly reduced.

Therefore, by applying the mounting technology of the present invention to, for example, a digital still camera, it becomes possible to realize a very small digital still camera.

[Brief description of the drawings]

FIG. 1 is a schematic perspective view showing an example of a very small digital still camera.

FIG. 2 is a schematic perspective view showing an inserted state of a memory element.

FIG. 3 is a schematic diagram illustrating an example of a mounting structure of an imaging device to which the present invention has been applied.

FIG. 4 is a schematic diagram showing a schematic configuration of a lens barrel.

FIG. 5 is a schematic diagram showing an example of a bare chip.

FIG. 6 is a schematic diagram showing a state in which bumps are formed on pads of a bare chip.

FIG. 7 is a schematic diagram showing a state in which a bare chip is mounted on a lens barrel.

FIG. 8 is a schematic diagram illustrating a process of attaching a lens barrel to a circuit board.

FIG. 9 is a schematic view showing a soldered state.

FIG. 10 is a schematic view showing a lens attaching step.

FIG. 11 is a schematic view showing another example of the shape of the lens barrel.

FIG. 12 is a schematic view showing still another example of the shape of the lens barrel.

FIG. 13 is a schematic diagram illustrating another example of a mounting structure of an imaging element to which the present invention is applied.

FIG. 14 is a schematic diagram illustrating an example of a conventional mounting structure of an image sensor.

[Explanation of symbols]

11 lens barrel, 12 bare chip, 13 circuit board, 14 lens, 15 wiring pattern

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Claims (6)

[Claims] 1. A mounting structure of an image pickup device, wherein the image pickup device is directly mounted on a lens barrel having an image pickup lens. 2. The mounting structure according to claim 1, wherein said image sensor is mounted on a lens barrel in a bare chip state. 3. The mounting structure according to claim 1, wherein the lens barrel is formed of a liquid crystal polymer. 4. The mounting structure according to claim 1, wherein the lens barrel is attached so as to penetrate a circuit board. 5. The imaging device according to claim 1, wherein a wiring is formed on a peripheral surface of the lens barrel, and the imaging device and a circuit board are electrically connected by the wiring. Mounting structure. 6. A lens barrel provided with an imaging lens on one surface of a circuit board, and an opening is formed in the circuit board corresponding to the lens barrel. An image sensor is mounted on a surface of the image sensor such that the light receiving part faces the opening.