JP2008124923A - The camera module - Google Patents

Abstract

Provided is a camera module in which an arrangement interval of a plurality of imaging elements and a manufacturing variation in an optical axis direction are reduced.
A three-dimensional wiring board 1 has an upper and lower cavity structure, and is provided with a recess 5 for mounting an electrical component on the lower side and two recesses 6 and 6 for mounting an optical component on the upper side. The component mounting recess 6 communicates with the electrical component mounting recess 5 through the through hole 7. Two image pickup devices 2 are flip-chip mounted in the electrical component mounting recess 5 with the light axis 2 facing the through hole 7 with the same optical axis direction. In each optical component mounting recess 6, a lens 3 and an IR filter 4 for allowing light to enter the image sensor 2 are installed.
[Selection] Figure 1

Description

  The present invention relates to a camera module.

Conventionally, a camera module in which an imaging element and a lens are mounted on a three-dimensional wiring board has been provided (see, for example, Patent Document 1).
JP 2001-245186 A (paragraph numbers [0022]-[0035] and FIG. 1)

  When a stereoscopic image is captured using the above-described camera module or the distance to an object in the captured image is measured using the principle of triangulation, a stereoscopic wiring board on which an image sensor and a lens are mounted one by one is used. Since two image elements are arranged at predetermined intervals and image signals input from the two image sensors are processed, the arrangement interval of the two image sensors and the manufacturing variation in the optical axis direction increase. There is a problem that an accurate stereoscopic image cannot be obtained or the distance measurement accuracy is deteriorated.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a camera module in which the arrangement interval of a plurality of imaging elements and manufacturing variations in the optical axis direction are reduced. is there.

  In order to achieve the above object, the invention of claim 1 is characterized in that a plurality of image pickup devices, a plurality of lenses that respectively allow light to enter the plurality of image pickup devices, and the optical axis directions of the plurality of image pickup devices are the same. It is characterized by comprising a three-dimensional wiring board on which a plurality of imaging elements and a plurality of lenses are mounted as directions.

  According to the first aspect of the present invention, since the plurality of image sensors and the plurality of lenses are mounted on the three-dimensional wiring board with the optical axis direction of each image sensor as the same direction, the arrangement interval of the plurality of image sensors. And a camera module with reduced manufacturing variations in the optical axis direction. Therefore, when this camera module is used for photographing a stereoscopic image or measuring a distance, an accurate stereoscopic image can be obtained and the distance measurement accuracy can be increased.

  Hereinafter, embodiments of the present invention will be described with reference to FIGS.

  FIG. 1 is a cross-sectional view of the main part of a camera module A. The camera module A is configured by mounting two image pickup devices 2, lenses 3, and IR filters 4 on a three-dimensional wiring board 1.

  The three-dimensional wiring board 1 has an upper and lower cavity structure, and is provided with an electrical component mounting recess 5 on which two image pickup devices 2 are flip-chip mounted on the lower side, and one lens 3 and one IR filter 4 on the upper side. Optical component mounting recesses 6 and 6 are provided at two locations on the left and right sides. A filter housing recess 8 having a smaller opening area than the upper portion is formed in the center of the bottom of each optical component mounting recess 6. The three-dimensional wiring board 1 is placed at the bottom of the filter housing recess 8. Through-holes 7 penetrating in the thickness direction are respectively formed. Thus, the optical component mounting recess 6 communicates with the electrical component mounting recess 5 via the through hole 7.

  The two image pickup devices 2 are constituted by a CCD (charge coupled device) or a CMOS image sensor having sensitivity to light in the visible light region. A conductor pattern 10 made of a metal plating layer is formed in the recess 5 for mounting electrical parts of the three-dimensional wiring board 1. By bonding, the chip is flip-chip mounted on the bottom of the electrical component mounting recess 5 with the light receiving portion 2 a facing the through hole 7. The conductor pattern 10 is provided around the electrical component mounting recess 5 and is extended to the distal end surface (lower surface) of the leg portion 12 protruding downward. The conductor pattern formed on the distal end surface of the leg portion 12 The soldering terminals 11 for soldering the three-dimensional wiring board 1 to a mounting board (not shown) are configured from the 10 parts.

  The IR filter 4 is a filter that cuts light in the ultraviolet region and transmits light in the visible region and infrared region, is formed in a flat plate shape, and is placed on the bottom of the filter housing recess 8. .

  The lens 3 is for making light incident on the image sensor 2, and is disposed on the step portions 9 and 9 on both sides of the filter housing recess 8 inside the optical component mounting recess 6.

The camera module A of the present embodiment has the above-described configuration, and light incident from the space to be imaged is collected by the lens 3, passes through the IR filter 4, and further passes through the through hole 7 to take an image. Here, since each of the two image pickup devices 2 and the lens 3 is mounted on the three-dimensional wiring board 1, the relative positions of the image pickup device 2 and the lens 3 are made incident on the light receiving portion 2 a of the element 2. The alignment can be performed with high accuracy, and further, the arrangement interval of the image pickup device 2 and the manufacturing variation in the optical axis direction can be reduced. Therefore, when creating a stereoscopic image based on the captured images of the two imaging elements 2, an accurate stereoscopic image can be obtained, and the distance to an object in the captured image using the principle of triangulation Is advantageous in that the distance measurement error can be reduced.

  By the way, in the above-described embodiment, an image sensor that converts an image in the visible light region into a video signal is used for the two image sensors 2, but one of the two image sensors as shown in FIG. 2. (Left side in FIG. 2) is the daytime imaging device 2 having sensitivity to light in the visible light region, and the other one (right side in FIG. 2) is light from the infrared region to the visible light region. The image sensor 13 may be a night vision image sensor 13 having a sensitivity to the image, and the image sensor 13 for night vision in addition to the image sensor 2 for daytime can obtain an image in both bright and dark environments. There is an advantage of becoming.

  As with the image sensor 2, the image sensor 13 is soldered to the conductor pattern 10 formed on the electrical component mounting recess 5 with the bump electrodes 13 b provided on the upper surface thereof with the light receiving portion 13 a facing the through hole 7. As a result, it is flip-chip mounted on the three-dimensional circuit board 1. The image sensor 13 is mounted on the three-dimensional circuit board 1 so that the optical axis direction thereof is the same as the optical axis direction of the image sensor 2.

  By the way, although the above-mentioned three-dimensional wiring board 1 is formed using the manufacturing technique of a three-dimensional three-dimensional circuit board, the manufacturing technique is demonstrated with reference to FIGS.

  FIG. 3 is a flowchart showing an outline of a method for manufacturing a three-dimensional circuit board. The three-dimensional three-dimensional circuit board is formed by a molding process (S1) in which a resin material is injection-molded to mold a desired three-dimensional substrate 21, and a physical vapor deposition method such as sputtering, vapor deposition, or ion plating on the surface of the substrate 21. A metallization process (S2) for forming the conductive thin film 22, a laser process (S3) for separating the circuit part / non-circuit part by a high energy beam (in this embodiment, a laser beam), and plating of the circuit part It is manufactured by sequentially performing each step of the plating process (S4) for forming the plating layer 23 by increasing the film thickness and the non-circuit part etching process (S5).

  4 (a) to 4 (c) and FIGS. 5 (a) and 5 (b) show the surface treatment of the three-dimensional circuit board B in each of the above steps. First, FIG. 4A shows a molding step (S1) of the substrate 21, and the substrate 21 having a desired three-dimensional shape is molded by injection molding an insulating synthetic resin. Here, as the molding material of the substrate 21, for example, an aromatic polyamide or liquid crystalline polyester is used in the case of a thermoplastic resin, an epoxy resin or a saturated polyester is used in the case of a thermosetting resin, and a nitriding is used in the case of a ceramic. Alumina or the like is used. The molding method of the substrate 21 is not limited to injection molding, and a molding method such as extrusion molding or transfer molding may be used.

  Next, FIG. 4B is a metallization process step (S2). For example, the surface of the substrate 21 is made conductive by a physical vapor deposition method (PVD method) such as sputtering, vacuum deposition, or ion plating using copper as a target. A thin film 22 is formed. However, it may be performed by other methods such as a chemical vapor deposition method without being limited to the physical vapor deposition method. In addition to copper, the conductive thin film 22 may use a single metal such as nickel, gold, aluminum, titanium, molybdenum, chromium, tungsten, tin, or lead, or an alloy such as brass or NiCr.

  FIG. 4C shows a laser processing step (S3). A boundary portion between the circuit portion 23a and the non-circuit portion 23b in the conductive thin film 22 is irradiated with a high energy beam, for example, a laser beam which is an electromagnetic wave beam, and the portion. The conductive thin film 22 is removed by evaporation, and the circuit portion 23a and the non-circuit portion 23b are separated by the removal portion 23c to form a predetermined circuit pattern.

  Next, FIG. 5A is a plating process step (S4). Electricity is supplied to the circuit portion 23a, current flows, the portion of the circuit portion 23a is thickened by, for example, electrolytic copper plating, and the plating layer 24 is formed. It is formed. At this time, no current flows through the non-circuit portion 23b, and the portion of the non-circuit portion 23b is not plated, so that the film thickness remains as it is. Note that nickel gold plating or the like may be formed as the plating layer 24.

  Next, FIG. 5B is an etching process step (S5). By etching the entire circuit pattern forming surface, the non-circuit portion 23b is removed and a three-dimensional circuit board on which the circuit pattern is formed is completed. Therefore, the above-described three-dimensional wiring board 1 can be formed using such a manufacturing technique.

  It should be noted that a wide variety of different embodiments can be configured without departing from the spirit and scope of the present invention, and the present invention is not limited to a specific embodiment.

It is a schematic sectional drawing of the camera module of this embodiment. It is a schematic sectional drawing of the other camera module same as the above. It is a flowchart which shows the outline | summary of the manufacturing method same as the above. (A)-(c) is a perspective view which shows the mode of the surface treatment in each process same as the above. (A) (b) is a perspective view which shows the mode of the surface treatment in each process same as the above.

Explanation of symbols

A camera module 1 three-dimensional wiring board 2 image sensor 2a light receiving part 3 lens 4 filter 5 concave part for mounting electrical parts 6 concave part for mounting optical parts 7 through hole

Claims (1)

  Equipped with multiple image sensors, multiple lenses that allow light to enter each of the multiple image sensors, and multiple image sensors and multiple lenses with the optical axis direction of the multiple image sensors as the same direction And a three-dimensional wiring board.

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