JP2007006475A - Camera module for mobile communication device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a camera module for mobile communication apparatus in which injection molding of a housing and a cover constituting a camera module with no lens barrel is facilitated for the camera module, the housing and cover are easily assembled and in component assembly, a lens/lens assembly and an imaging element are accurately focused to improve a horizontal resolution. <P>SOLUTION: A camera module with no lens barrel includes: an imaging element wire-bonded on a soft circuit board; a hollow type housing fixed on the soft circuit board so that the imaging element is positioned inside, and incorporating an infrared cut-off filter for protecting the imaging element from infrared rays; a lens or lens assembly built in the housing so as to be positioned above the infrared cut-off filter; and a cover formed with a lens hole in the center of its upper surface while being supported/fixed on an upper end face of the housing. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a camera module of a mobile communication device having no lens barrel. 1) The injection molding of the housing and the cover forming the exterior of the camera module is easy. 2) The assembly of the housing and the cover is easy. 3) This relates to the camera module of a mobile communication device that improves the horizontal resolution by accurately focusing the lens / lens assembly and the image sensor when assembling the parts.

  With the development of semiconductor technology and IT technology, new products in the form of new products with camera functions and MP3 functions added to mobile communication devices such as mobile phones are being released one after another. In particular, in the case of a mobile phone, the camera function is almost essential, but the mobile phone itself is becoming lighter / smaller / thinner on a daily basis. Modules are also required to be ultra-light / ultra-compact to follow this trend.

  The attached FIG. 1 is a cross-sectional view taken in a vertical direction to examine a general configuration of a camera module applied to a conventional mobile phone. As shown in FIG. The image sensor (1) mounted on the flexible circuit board (FPCB) (10) and wire-bonded is protected by a housing (2) containing an infrared cut-off filter (3), and the lens ( The lens barrel (5) containing 4) is screwed to the upper end side of the housing (2).

  By the way, according to such a conventional camera module, there are the following problems when assembling parts as well as parts.

  For example, due to problems when manufacturing parts: 1) Although the screw threads for mutual fastening must be machined on the inner surface of the upper end side of the housing (2) and the outer surface of the lens barrel (2), these parts are large. In addition to being very small in size, it is difficult to manufacture injection molds, and there is a disadvantage that cost increases are unavoidable because precision processing is required for the manufacture of the mold. 3) The defect rate is high because the screw thread is easily damaged or deformed when it is taken out. 3) In this way, the defect rate is high, so it is often used in the pre-inspection process where parts are assembled from the assembler in the subsequent process. These problems are all included in the cost, which increases the unit price of production, and thus reduces the price competitiveness in the market.

  Also, there are problems when assembling parts: 4) The screw fastening system that turns one of the two parts to the other, and the assembly speed of the parts is slow. 5) Small screw thread However, when it is assembled by alternately biting, there is a disadvantage that the center axis (focal point) of the lens in the lens barrel and the image sensor do not match and the horizontal resolution decreases. Although all camera modules are disposed of, the amount reaches about 30% of the total production, which is a significant cost factor.

  The object of the present invention is to process the inner surface of the housing with the original peripheral surface without screw threads and directly assemble the lens or lens assembly into the housing, and then cover the upper end of the housing with the lens hole. Covering the housing and cover makes it easy to inject and mold the housing and cover, and the lens / lens assembly and the image sensor are accurately focused during assembly to improve horizontal resolution. It is to provide a camera module for mobile communication devices.

  To achieve the above-mentioned purpose, an image sensor wire-bonded to a soft circuit board and an infrared shielding filter that is fixed on the soft circuit board so that the image sensor is located inside and protects the image sensor from infrared rays are incorporated. A hollow housing, a lens or a lens assembly incorporated in the housing so as to be positioned above the infrared shielding filter, and a lens hole in the center of the upper surface while being supported and fixed to the upper end surface of the housing. (Claim 1) Here, the lens assembly can be composed of at least two or more lenses and a spacer that is sandwiched between the lenses to ensure a distance between the lenses. (Claim 2), a ring-shaped cap (not shown) so that the lens / lens assembly can be detached from the housing or does not move in the housing. ) Can be additionally sandwiched in the housing after the built-in lens / lens assembly. Also, in order to adjust the distance between the lens / lens assembly and the image sensor, the internal step of the housing and the lens / lens assembly can be adjusted. An additional liner can be interposed between the two (claim 3).

  The presently preferred embodiments of the present invention will be described with reference to the accompanying drawings in the following examples.

  However, it will be understood that there is a possibility of adjustment or improvement without departing from the spirit and scope of the present invention by referring to the contents published by those skilled in the art.

2 is a cross-sectional view of a camera module according to an example of the present invention. In the drawing, the image pickup device (11) die-bonded to the flexible circuit board (10) is connected to the flexible circuit board (10). Thereafter, the housing (12) for isolating the image sensor (11) from the external environment is placed on the flexible circuit board (10) and fixed with an adhesive. An infrared shielding filter (13) is bonded and fixed to the internal step (21) of the housing (12), and the infrared rays entering the image sensor (11) are blocked by the filter. On the upper surface of (21), a ring-shaped thin liner (22) made in advance for various thicknesses to adjust the focal length which changes little by product is placed. The overall shape is convex A lens assembly (16) composed of two micro lens (16a) and a ring-shaped thin film type spacer (19) sandwiched between the two lenses is placed. In this way, when the housing 12 is fixed on the flexible circuit board 10 and the lens assembly is built in the housing, the cover 18 is placed on the opened upper portion of the housing 12. The cover (18) is sandwiched by the open upper end of the housing (12) so that the coupling position is fixed, and the cover (18) and the cover are fixed. There is a support step (17) supported on the upper end surface of the housing, and there is a lens hole (15) in the center of the upper surface. Here, an adhesive can be used for bonding between parts.

  According to the present example configured as described above, since no screw thread is formed on the inner and outer surfaces of the housing (12) and the cover (18), it is easy to take out these parts from the plastic injection mold. In addition, it is possible to prevent parts from being damaged during the demolding process. Also, since the coupling between the housing (12) and the cover (18) is sandwiched and combined, the assembly speed can be greatly improved compared to the conventional screw fastening system. In addition, if the thickness of the liner (22) and the thickness of the internal step (21) are adjusted during the manufacturing process, the focal length between the lens assembly (16) and the image sensor (11) is automatically adjusted. It is possible to accurately match up to the focal point while aligning with, and prevent horizontal resolution from being degraded due to poor assembly.

  As explained and confirmed above, the camera module of the mobile communication device according to the present invention allows easy injection molding of the housing and the cover, and the assembly between the parts can be done at a very high speed. The focal length and focus between the sensor and the image sensor are automatically and accurately adjusted to improve the horizontal resolution of the image. Also, the defective rate of parts is low and the cost of machinery such as molds used for parts production is reduced. Price competitiveness in the market.

The foregoing invention and other objects, features and other advantages of the present invention will be more clearly understood from the following detailed description of the accompanying drawings. The accompanying drawings are described below. .
It is a model diagram showing a cross section of a conventional camera module. Is a cross-sectional view of a camera module according to an example of the present invention.

Explanation of symbols

1, 11 Image sensor
2, 12 Housing 3, 13 Infrared shielding filter 4, 16a Lens 5 Lens barrel 10 Soft circuit board 15 Lens hole 16 Lens assembly 17 Support step
18 Cover 19 Spacer 21 Internal step 22 Liner

Claims (3)

An image sensor wire bonded to a flexible circuit board;
A hollow housing that is fixed on a flexible circuit board so that the image sensor is located inside and that contains an infrared shielding filter that protects the image sensor from infrared rays;
A lens or a lens assembly incorporated in the housing so as to be located above the infrared shielding filter;
A cover having a lens hole formed in the center of the upper surface while being supported and fixed to the upper end surface of the housing;
Mobile communication device camera module including.   The camera module of the mobile communication device according to claim 1, comprising a lens assembly comprising at least two or more lenses and a spacer for securing a distance between the lenses sandwiched between the lenses. Camera module of communication device. The camera module of the mobile communication device according to claim 1 or 2, wherein a liner is interposed between the internal step of the housing and the lens or the lens assembly, and the lens or the lens assembly and the imaging device. Camera module of mobile communication device that adjusts the distance between.

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