JP2011128556A - Camera module and method for manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a small camera module in which a wiring distance is short. <P>SOLUTION: The camera module 1 includes: a circuit substrate 10, as a sensor cover, having a light-transmitting portion and mounted so that the imaging area of an imaging element is located in an area corresponding to the light-transmitting portion; a lens unit 40 disposed in the front side of the light-transmitting portion; and an actuator 12 for driving the lens unit 40. The camera module 1 is configured such that power is fed to the actuator via the circuit substrate 10. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a camera module and a method for manufacturing the same, and more particularly to a camera module that realizes power supply to an actuator that drives a zoom mechanism via a sensor cover that constitutes the camera module.

Small camera modules for mobile phones are increasing in pixel count. As a result, the size of the image sensor tends to increase, but there is still a strong demand for downsizing and thinning of the mobile phone body, and the larger image sensor can be carried in the same or a smaller space as before. Must be placed in the phone.
Among these requirements, by replacing the molded product used as the cover of the image sensor, that is, the sensor cover with MID (Molded Interconnect Device: injection molded circuit component) and arranging electronic components inside the sensor cover, There has been proposed a camera module that effectively utilizes the volume of the camera module to reduce the size of the package.

Along with the recent increase in the number of pixels, a module having an autofocus (AF) function has also been proposed.
The module having the AF function uses a VCM actuator that drives a lens unit using a coil and a magnet, and a piezo actuator that drives a lens unit by expansion and contraction of a piezoresistive element. There is a thing (for example, patent document 1).

  In the latter case, as shown in FIG. 5, the lens unit 1040 is driven by mounting an actuator including a piezoresistive element 1012 in the housing 1001 and moving a guide shaft 1042 connected to the piezoresistive element 1012. The condensing to the solid-state image sensor 1020 is configured to be adjusted. Such a conventional piezoelectric actuator is simplified as shown in FIG. 6, and the periphery of the image sensor 1020 and the periphery of the actuator are separate parts. In addition to supplying power to the electronic component 1022 in the sensor cover 1011, It is necessary to separately supply power to the actuator 1012 side.

JP 2005-351948 A

In such a case, the wiring needs to be taken out from the mounting substrate 1000, whether the camera module is mounted. Therefore, wiring is long and various attempts have been made for further miniaturization.
The present invention has been made in view of the above circumstances, and an object thereof is to provide a small camera module with a small wiring routing distance.

Therefore, the camera module of the present invention includes a circuit board that has a light-transmitting portion and is mounted so that the imaging region of the imaging element is located in a region corresponding to the light-transmitting portion, and is disposed on the front side of the light-transmitting portion. A lens unit, an actuator that drives the lens unit, and a sensor cover that holds a main body portion of the actuator, and the power is supplied to the actuator through the circuit board. It is characterized by that.
According to this configuration, since power is supplied from the mounting board to the actuator via the circuit board, the wiring length can be shortened, the electrical loss is small, the size is small, and the wiring is exposed outside the camera module. Therefore, it is possible to provide a camera module with excellent appearance.

Therefore, the present invention includes the camera module described above, wherein the circuit board is a multilayer wiring board having internal wiring.
According to this configuration, a more compact mounting is realized.

Therefore, the present invention includes the camera module described above, wherein the circuit board includes an external connection terminal for supplying power from an external power source.
According to this configuration, since it is connected to the external power supply via the external connection terminal formed on the circuit board, the external connection terminal can be arranged at a position very close to the actuator, and wiring routing is reduced. In addition to the reduction in wiring resistance, the appearance is improved.

Therefore, the present invention is the camera module, wherein the circuit board is a three-dimensional circuit board, and is a cylindrical body having an intermediate support part having an opening in the center, and the intermediate support part is closed so as to close the opening. An image pickup device disposed on the first surface of the substrate, a translucent member disposed on the second surface of the intermediate support portion so as to close the opening, and a piezoresistive device mounted on the three-dimensional circuit board. Including an actuator comprising:
According to this configuration, it is possible to provide an extremely small and thin camera module having an AF function.

  According to the camera module of the present invention, it is possible to provide a camera module that is small, thin, and excellent in appearance.

1 is a schematic diagram showing a camera module according to a first embodiment of the present invention. Sectional drawing which shows the camera module of embodiment of this invention Explanatory drawing showing the drive principle of the actuator Schematic diagram showing a camera module of Embodiment 2 of the present invention Schematic diagram showing a conventional camera module Schematic diagram showing a conventional camera module

  Hereinafter, a camera module according to an embodiment of the present invention will be described with reference to the drawings.

(Embodiment 1)
As shown in the schematic explanatory diagram of FIG. 1, the camera module 1 has a translucent portion R, and an imaging region of a CCD image sensor as the imaging element 20 is located in a region corresponding to the translucent portion R. The circuit board 10 constituting the sensor cover mounted on the lens, the lens unit 40 disposed on the front side of the light transmitting portion R, and the actuator 12 for driving the lens unit 40, and the actuator constituting the sensor cover 12 is configured so that power is supplied to the circuit board 10 via a terminal 11 formed on the circuit board 10.

  In this camera module, as shown in FIG. 2, a substrate 10, which is a three-dimensional circuit substrate formed of a ceramic laminated substrate, is formed of a cylindrical body having an intermediate support portion 14 having an opening 13 at the center. Then, the image pickup device 20 disposed on the first surface 14A of the intermediate support portion 14 so as to close the opening 13 and the second surface 14B of the intermediate support portion so as to close the opening 13 are arranged. It arrange | positions so that the filter 15 as a translucent member may oppose. Further, the electronic component 22 such as a processing circuit is embedded in a three-dimensional wiring board formed of a laminated board.

  The upper portion of the circuit board 10 has a reduced diameter, and an actuator 12 made of a piezoresistive element is mounted on a flat portion formed by the reduced diameter. Power is supplied to the actuator from the terminal 11 via an internal wiring (not shown) in the circuit board 10.

  FIG. 3 shows the driving principle of this actuator. An actuator 12 made of a piezoresistive element is attached to one end of the beam 18 supported by the fulcrum O, and a spring 17 is attached to the other end, and the beam 18 is pushed in the direction of the actuator 12 made of a piezoresistive element by the elastic force of the spring 17. The beam 18 is brought into contact with the actuator 12 made of a piezoresistive element. In this state, the lens support 41 fixed to the beam 18 is displaced.

  As shown in FIG. 2, the actuator 12 is installed so as to contact the guide shaft 42, and the lens support portion 41 of the lens unit 40 slides on the guide shaft 42, so that the lens of the lens unit is aligned with the optical axis. Move along.

  Further, a chip component 1010 is also mounted on the back surface of the mounting substrate 1000 on which this circuit board is mounted. On the front surface side, the CCD image sensor and its output signal are electrically corrected, and the camera resolution, color tone, A DSP chip 30 (digital signal processor) for correcting shading and the like is mounted.

The image sensor 20 is a CCD image sensor chip.
Note that a so-called system-on-chip (SOC) type solid-state imaging device in which a circuit having a DSP function is arranged around the sensor unit of the imaging device 20 may be used.
This makes it possible to further reduce the size.

According to this configuration, since power is supplied to the actuator 12 via the circuit board 10, the wiring length can be shortened, and there is provided a camera module that has a small electrical loss, is small, and has excellent appearance. It becomes possible.
That is, it can be seen that the implementation of the present invention is effective in reducing the size of the camera module.

  In addition, as a translucent member, you may use what formed the filter film | membrane or the antireflection film in the translucent board | substrate, without being limited to a filter. In that case, the optical characteristics can be further improved.

  In the present embodiment, the circuit board 10 constituting the sensor cover is constituted by a three-dimensional wiring board. When the ceramic green sheets are laminated, the electronic parts (chip parts) 22 such as processing circuits are stacked and fired. By doing so, the electronic component 22 can be embedded in the three-dimensional wiring board.

  Reference numeral 50 denotes a stop, but the function of driving the stop can also be integrated in the DSP chip. A diaphragm actuator may be provided separately.

(Embodiment 2)
In the above embodiment, the electronic component (chip component) 22 such as a processing circuit is embedded in a three-dimensional wiring board formed of a multilayer substrate. However, as shown in FIG. You may mount on the inner wall of the circuit board 10 which comprises a cover, or on. According to this configuration, even if the wiring becomes complicated, the wiring can be efficiently performed with the shortest wiring length. Therefore, the exclusive area required for the wiring can be reduced and the size can be reduced. The operating speed can be improved by reducing the resistance. In this case, the three-dimensional wiring board may be a resin board formed by injection molding. Then, by forming wiring on the resin substrate and mounting the electronic component 22, it is possible to form a small camera module.

In the present invention, in the imaging apparatus, the plurality of imaging elements may be integrated on the same substrate. In this case, in the region facing the image sensor, the wiring is disposed so as to face the wiring region surrounding the light receiving area of the image sensor.
According to this configuration, for example, by forming the wiring on the charge transfer portion, it is possible to facilitate the wiring while suppressing a decrease in the amount of received light.

In the above-described embodiment, a laminated substrate using a green sheet and a resin three-dimensional substrate formed by injection molding are used as the circuit substrate, but various substrate materials can be applied. For example, it is made of a ceramic dielectric material LTCC (Low Temperature Co-fired Ceramics) that can be sintered at a low temperature of 1000 ° C. or lower, and is formed on a green sheet having a thickness of 10 μm to 200 μm with a low resistivity of Ag or A conductive paste such as Cu is printed to form a predetermined pattern, and a plurality of green sheets are used as an insulating layer, and are integrally laminated as appropriate, and sintered to provide an insulating layer (dielectric material) Layer). As these dielectric materials, for example, Al, Si, Sr as main components, Ti, Bi, Cu, Mn, Na, K as subcomponents, Al, Si, Sr as main components, Ca, Pb A material containing Na, K as a multicomponent, a material containing Al, Mg, Si, Gd, or a material containing Al, Si, Zr, Mg is applicable. Here, a material having a dielectric constant of about 5 to 15 is used. In addition to the ceramic dielectric material, it is also possible to use a resin multilayer substrate or a multilayer substrate made of a composite material obtained by mixing a resin and ceramic dielectric powder. Further, the ceramic substrate is made of HTCC (High Temperature Co-fired Ceramics) technology, the dielectric material is mainly Al ₂ O ₃ , and the transmission line is made of tungsten or the like as the internal conductor layer. You may comprise as a metal conductor which can be sintered at high temperature, such as molybdenum.

  Moreover, it is applicable to other ceramics without being limited to the green sheet, and when a resin substrate such as glass epoxy resin, polyimide resin, polyester resin, polyethylene terephthalate resin is used, a laminated substrate using a prepreg It is also applicable to.

  As mentioned above, although embodiment which applied the invention made by the present inventors was described, this invention is not limited by description and drawing which make a part of indication of this invention by this embodiment. That is, it is needless to say that other embodiments, examples, operation techniques, and the like made by those skilled in the art based on the above-described embodiments are all included in the scope of the present invention.

DESCRIPTION OF SYMBOLS 1 Camera module 10 Circuit board 11 Terminal 12 Actuator 13 Opening part 14 Intermediate | middle support part 14A 1st surface 14B 2nd surface 15 Filter 20 Image pick-up element 22 Electronic component 30 DSP chip 41 Lens support part 42 Guide shaft 50 Diaphragm 1000 Mounting board 1010 Chip components

Claims (4)

A circuit board having a light transmitting portion and mounted so that an imaging region of the imaging element is located in a region corresponding to the light transmitting portion;
A lens unit disposed on the front side of the translucent part;
An actuator for driving the lens unit;
A camera module having a sensor cover for holding a main body portion of the actuator,
A camera module configured to supply power to the actuator via the circuit board. The camera module according to claim 1,
The circuit board is a camera module which is a multilayer wiring board having internal wiring. The camera module according to claim 1 or 2,
The circuit board is a camera module having an external connection terminal for supplying power from an external power source. The camera module according to claim 1 or 2,
The circuit board is a three-dimensional circuit board;
A cylindrical body having an intermediate support portion having an opening in the center;
An imaging device disposed on the first surface of the intermediate support portion so as to close the opening;
A translucent member disposed on the second surface of the intermediate support portion so as to close the opening;
A camera module comprising an actuator comprising a piezoresistive element mounted on the three-dimensional circuit board.

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