Camera module and method for manufacturing a camera module

Abstract

The present invention consists of at least one wiring board (2), at least one image sensor (7), at least one camera housing (4), and a lens module (5). A single support plate (3) is arranged between the wiring board (2) and the camera housing (4). The support plate (3) is fixedly connected to the wiring board (2), and the support plate (3) and the wiring board (2) together form an electronic module, which is a camera module (1). The support plate (3) is connected to the camera housing (4) by a material bonding process in the positioning process of the image sensor (7) and the optical axis (O) and / or the image plane of the lens module (5). A correction gap (6) is provided around the entire circumference between the support plate (3) and the housing (4), and material bonding (8) is formed at the four corners of the camera housing (4). The present invention relates to a camera module characterized by this.

Description

Technical Field

[0001] The present invention relates to a camera module and a method for manufacturing a camera module.

Background Art

[0002] As a conventional technique, for example, a camera having a support means is known from Document WO2016112890A1. The support means is disposed between an image sensor and a printed circuit board and is at least partially surrounded by an outer wall of a camera housing.

[0003] From Document WO2011120480A1, optical means including an optical module, a wiring board, an image capturing element, and a support plate are known. An optical module and an image capturing element are disposed on one side of the support plate, and a wiring board is disposed on the opposite side. Further, from Document WO2011120481A1, optical means including a lens holder are known. A connection surface for forming an adhesive connection surrounding the optical axis of the optical means in the radial direction is provided between the optical module and the lens holder.

[0004] In addition, from Document DE102017124550A1, a camera for a motor vehicle including a housing, a wiring board on which an image sensor of the camera is disposed, and at least two support elements connected to the first wiring board and the housing is known. The first wiring board is supported at a distance from the housing by the two support elements and is electrically connected to the housing. The housing has a front housing portion and a rear housing portion. The front housing portion and the rear housing portion are electrically connected to each other and are connected to each other by a welding connection.

[0005] The problems in these conventional techniques are the optical stability and tolerance accuracy of an image sensor (bare die, BGA, CSP structure) with respect to the optical and mechanical axes of an optical module of a camera or a camera housing. [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] WO2016112890A1 [Patent Document 2] WO2011120480A1 [Patent Document 3] WO2011120481A1 [Patent Document 4] DE102017124550A1 [Overview of the project] [Problems that the invention aims to solve]

[0007] Therefore, the object of the present invention is to provide a camera module and a manufacturing method, the camera module having improved tolerance precision and optical stability.

[0008] The above objectives are achieved by independent claims 1 and 6.

[0009] Further preferred forms are the subject of the dependent claims.

[0010] First, we considered that in conventional camera modules, the image sensor needs to be properly positioned relative to the optical axis, and therefore, in many cases, it consists of multiple substrates stacked perpendicular to the optical axis. The alignment of the image sensor with respect to the lens's focal position is performed by a 5-axis or 6-axis alignment process. The variability caused by the tolerance of the focal position makes it difficult for OEMs to integrate the camera. As a result, component costs are high for both OEMs and sensor manufacturers.

[0011] The front and back of the electronic module have through-holes for the lens (front) or plug (rear), so they are not useful for direct thermal connection. Therefore, direct heat dissipation from the processor IC or the outside of the module is difficult because the wiring board and IC are often positioned parallel to the image sensor. As a result, heat accumulates inside the camera housing, the image sensor thickens, and consequently, noise increases and image quality deteriorates.

[0012] Accordingly, the present invention proposes a camera module comprising at least one wiring board, at least one image sensor, at least one camera housing, and a lens module, wherein a support plate is positioned between the wiring board and the camera housing, the support plate is fixedly connected to the wiring board, and the support plate together with the wiring board forms an electronic module. However, in this case, the support plate is connected to the camera housing by a material bonding process during the positioning process of the optical axis and / or image plane of the image sensor and the lens module, and a correction gap is provided around the entire circumference between the support plate and the housing, and material bonding is applied to the four corners of the camera housing. Department It is formed.

[0013] The support plate can be connected to the wiring board by TOX joints or punched joints. Each support means may have at least two opposing edges to hold the wiring board in a fixed position on the support plate.

[0014] By employing this support plate, it is possible to configure an electronic module that opens up the possibility of introducing new connection technologies in the 5 / 6 axis adjustment process.

[0015] Similarly, the image sensor can also be placed on a wiring board or support plate.

[0016] This compensation gap compensates for irregularities and manufacturing tolerances during the positioning process, enabling more accurate alignment.

[0017] The camera module is preferably used in a vehicle as a satellite monocamera, or, for example, by arranging multiple modules to form a surround view system.

[0018] In a preferred embodiment, the positioning step is a 5-axis or 6-axis alignment between the optical axis and / or image plane of the image sensor and the lens module.

[0019] In one further preferred embodiment, laser welding is used as the material joining process. This material joining process is advantageous because laser welding is very precise. Subsequently, the small thermal strain generated is also advantageous in terms of accurately aligning the image sensor with respect to the optical axis and / or image plane.

[0020] Furthermore, it is preferable that at least the support plate and camera housing be made of the same material. By using the same material for the optical module (lens module + camera housing) and the electronic module (support plate + wiring board), it becomes possible to consider adopting bonding technology as a material joining process during camera assembly (e.g., laser welding) without incurring additional costs. As a result, improvements in optical stability throughout the entire lifecycle and improved tolerances between the optical system and the camera housing are achieved. Moreover, a cost-optimized bonding process can be used for attaching the lens module. This optimized electronic module enables the modularization of various image sensor technologies.

[0021] Subsequently, the image sensor is preferably arranged as a bare die, ball grid array, chip scale package or flip chip on the wiring board. By using a bare die, the image sensor provides further advantages. Due to the effect of the inner support plate, thermal insulation of the image sensor is possible simply by mounting it on the support plate. The support plate is designed to have a hole geometry around the image sensor. By mounting the wiring board from the back side of the support plate, the image sensor can be directly connected to the wiring board using a thin / thick wire / bonding process. Furthermore, the support plate can function as a heat dissipation and heat radiating plate, for example, when made of metal, or as a heat insulating material, for example, when made of synthetic resin. In addition, it can be miniaturized without increasing costs. Also, a short signal path also has a good effect on EMC interference.

[0022] Subsequently, the present invention also relates to a method for manufacturing a camera module composed of a wiring board, an image sensor, a camera housing and a lens module, wherein a support plate is arranged between the wiring board and the camera housing. Here, however, the following steps are proposed: - Providing a wiring board and a support plate; - Connecting the image sensor to the wiring board or the support plate, and further connecting the wiring board to the support plate to form an electronic module; - Providing a camera housing with a lens module; - Aligning the image sensor with the optical axis and / or the image plane of the lens module in a positioning step; - Connecting the support plate to the four corners of the camera housing by a material joining process, provided that a correction gap (6) is provided all around between the support plate and the camera housing (4).

[0023] In a preferred embodiment of this method, the material joining process is a laser welding method.

[0024] Furthermore, the positioning process is particularly preferably a 5-axis or 6-axis alignment between the optical axis and / or image plane of the image sensor and the lens module.

[0025] In one other preferred embodiment, the thermal and / or electrical connection between the camera housing and the support plate is generated by a material bonding process.

[0026] Further preferred forms and embodiments are depicted in the drawings. [Brief explanation of the drawing]

[0027] [Figure 1] This is a schematic diagram of a camera module according to one embodiment of the present invention. [Figure 2a] This is a cross-sectional view of a camera module according to one embodiment of the present invention. [Figure 2b] This is a cross-sectional view and a magnified view of a part thereof of a camera module according to one embodiment of the present invention. [Figure 3] This is a further cross-sectional view and an enlarged view of a part thereof of a camera module according to a further embodiment of the present invention. [Figure 4] This is a schematic flowchart of a method according to one embodiment of the present invention. [Modes for carrying out the invention]

[0028] Figure 1 shows a schematic representation of a camera module according to one embodiment of the present invention. The camera module 1 consists of a wiring board 2, a support plate 3, a camera housing 4, and a lens module 5. The support plate 3 is positioned between the wiring board 2 and the camera housing 4. The support plate 3 has support elements 3a on the side facing the wiring board 2 that hold at least two wiring boards 2 in place when connected to the support plate 3. Subsequently, a correction gap 6 is provided around the entire circumference between the support plate 3 and the camera housing 4.

[0029] Figure 2a shows a cross-sectional view of a camera module according to one embodiment of the present invention. Cross-sectional view AA of the camera module 1 in Figure 1 shows the wiring board 2, support plate 3, housing 4 and lens module 5 in addition to material bonding. Department It indicates 8. Furthermore, material bonding Department 8 is preferably formed in the corner of the camera housing 4 or support plate 3 between the support plate 3 and the camera housing 4. Subsequently, on the side of the printed circuit board 2 facing the lens module 5 image The image sensor 7 is shown. During the positioning process or 5 / 6-axis alignment, the image sensor 7 is aligned with the optical axis O and / or image plane of the lens module 5. However, it is also possible to place the image sensor 7 on the side of the support plate 3 facing the lens module 5, and the wiring board on the opposite side of the support plate 3 from the lens module 5. In this case, the image sensor 7 is connected to the wiring board via wire bonds.

[0030] Figure 2b shows a cross-sectional view and a magnified view of a part thereof of a camera module according to one embodiment of the present invention. In the magnified view B, in particular, the material joint, which is a weld seam of, for example, a laser welding method. Department 8 and the correction gap 6 are more clearly visible. All other elements are essentially the same as in Figure 2a. Material bonding Department As shown in the figure, 8 is formed between the support plate 3 and the camera housing 4, and covers the correction gap 6 at least at the connection point, preferably at the corner of the housing 4. Department As shown in the figure, component 8 is located on the outside of the support plate and on the top of the camera housing 4.

[0031] Figure 3 is a further cross-sectional view and a magnified view of a part thereof of a camera module according to a further embodiment of the present invention. Partial magnified view C also shows essentially the same elements as those shown in partial magnified view B. In this embodiment, only the support plate 3 holds the wiring board 2 and has support elements 3a that can be used, for example, to connect the wiring board 2 and the support plate 3. Here, material contact If Department 8 is also formed between the support plate 3 and the camera housing 4. In this case, material bonding Department 8 is formed between the outside of the support plate 3 and the outside of the camera housing 4.

[0032] Figure 4 shows a schematic flowchart of a method according to one embodiment of the present invention. In step S1, a wiring board 2 and a support plate 3 are prepared. In step S2, at least an image sensor 7 is connected to the wiring board 2 or the support plate 3, and subsequently, the wiring board 2 and the support plate 3 are connected to form an electronic module. In step S3, a camera housing 4 with a lens module 5 is prepared, and subsequently, in step S4, the image sensor is aligned to the optical axis O and / or image plane of the lens module 5 in a positioning step. In step 5, the support plate 3 is connected to the four corners of the camera housing 4 by a material bonding process, with a correction gap 6 provided around the entire circumference between the support plate 3 and the camera housing 4. Steps S1 and S2 can be carried out in parallel with step S3. Therefore, the electronic module and the optical module can be manufactured in parallel, and then positioning can be carried out in step S4. Depending on the design of the electronic module, the image sensor can be connected to either the wiring board or the support plate. When connecting to a support plate, for example, an image sensor can be connected to a wiring board by wire bonding. This application relates to the invention described in the claims, but also includes the following other embodiments. 1. A camera module (1) comprising at least one wiring board (2), at least one image sensor (7), at least one camera housing (4), and a lens module (5), wherein a support plate (3) is positioned between the wiring board (2) and the camera housing (4), the support plate (3) is fixedly connected to the wiring board (2), and the support plate (3) together with the wiring board (2) forms a single electronic module, A camera module characterized in that a support plate (3) is connected to a camera housing (4) by a material bonding process during the positioning process of the optical axis (O) and / or image plane of the image sensor (7) and the lens module (5), and a correction gap (6) is provided around the entire circumference between the support plate (3) and the housing (4), and material bonding portions (8) are formed at the four corners of the camera housing (4). 2. The camera module (1) according to the above-mentioned invention, characterized in that the positioning step is a 5-axis or 6-axis alignment between the optical axis (O) and / or the image plane of the image sensor (7) and the lens module (5). 3. The camera module (1) described above, characterized in that a laser welding method is used as the material joining process. 4. The camera module (1) according to the above-mentioned invention, characterized in that at least the support plate (3) and the camera housing (4) are made of the same material. 5. The camera module (1) described above, characterized in that the image sensor (7) is arranged on a wiring board (2) as a bare die, a ball grid array, a chip-scale package, or a flip chip. 6. A method for manufacturing a camera module (1) comprising a wiring board (2), an image sensor (7), a camera housing (4), and a lens module (5), wherein a support plate (3) is positioned between the wiring board (2) and the camera housing (4), comprising the following steps: - Step (S1) of providing a wiring board (2) and a support plate (3); an image sensor (7); - Step (S2) involves connecting the image sensor (7) to the wiring board (2) or the support plate (3), and further connecting the wiring board (2) to the support plate (3) in order to form an electronic module; - Step (S3) of providing a camera housing (4) equipped with a lens module (5); -In the positioning process, step (S4) is to align the image sensor (7) with the optical axis (O) and / or image plane of the lens module (5); - Step (S5) connects the support plate (3) to the camera housing (4) at the four corners of the camera housing (4) by a material bonding process, provided that a correction gap (6) is provided around the entire circumference between the support plate (3) and the camera housing (4). 7. The method of the above sixth, characterized in that the material joining process is a laser welding method. 8. The method of the above-mentioned 6, characterized in that the positioning step is a 5-axis or 6-axis alignment between the optical axis (O) and / or the image plane of the image sensor (7) and the lens module (5). 9. The method of 6, characterized in that the thermal and / or electrical connection between the camera housing (4) and the support plate (3) is generated by a material bonding process. [Explanation of Symbols]

[0033] 1 Camera Module 2 Wiring board 3. Support plate 3a Support element 4 Camera Housing 5 Lens Modules 6. Correction Gap 7 Image Sensor 8. Material joining Department AA Cross-sectional view B. Partial enlarged view C. Partial enlarged view O optical axis S1-S5 Method Steps

Claims

1. A camera module (1) comprising at least one wiring board (2), at least one image sensor (7), at least one camera housing (4), and a lens module (5), wherein a support plate (3) is disposed between the wiring board (2) and the camera housing (4), the camera housing (4) surrounds the lens module (5) in the circumferential direction, the image sensor (7) is disposed on the side of the wiring board (2) or the support plate (3) facing the lens module (5) and is aligned with the optical axis (O) and / or image plane of the lens module (5), the support plate (3) is fixedly connected to the wiring board (2), and the support plate (3) together with the wiring board (2) forms a single electronic module in the camera module (1), A camera module (1) is characterized in that a support plate (3) is connected to a camera housing (4), a correction gap (6) is provided around the entire circumference between the support plate (3) and the housing (4), and material joints (8) are formed at the four corners of the camera housing (4).

2. The camera module (1) according to claim 1, characterized in that the material joint (8) is a joint formed by laser welding.

3. The camera module (1) according to claim 1, characterized in that at least the support plate (3) and the camera housing (4) are made of the same material.

4. The camera module (1) according to claim 1, characterized in that the image sensor (7) is arranged on a wiring board (2) as a bare die, a ball grid array, a chip-scale package, or a flip chip.

5. A method for manufacturing a camera module (1) comprising a wiring board (2), an image sensor (7), a camera housing (4), and a lens module (5), wherein a support plate (3) is positioned between the wiring board (2) and the camera housing (4), the camera housing (4) surrounds the lens module (5) in the circumferential direction, and the image sensor (7) is positioned on the side of the wiring board (2) or the support plate (3) facing the lens module (5) and is aligned with the optical axis (O) and / or image plane of the lens module (5), comprising the following steps: - Step (S1) of providing a wiring board (2), a support plate (3), and an image sensor (7), - Step (S2) of connecting the image sensor (7) to the wiring board (2) or the support plate (3), and further connecting the wiring board (2) to the support plate (3) in order to constitute an electronic module. - Step (S3) of providing a camera housing (4) equipped with a lens module (5), - In the positioning process, step (S4) aligns the image sensor (7) with the optical axis (O) and / or image plane of the lens module (5), - Step (S5) connects the support plate (3) to the camera housing (4) at the four corners of the camera housing (4) by a material bonding process, provided that a correction gap (6) is provided around the entire circumference between the support plate (3) and the camera housing (4).

6. The method according to claim 5, characterized in that the material joining process is a laser welding method.

7. The method according to claim 5, characterized in that the positioning step is a five-axis or six-axis alignment between the optical axis (O) and / or the image plane of the image sensor (7) and the lens module (5).

8. The method according to claim 5, characterized in that the thermal and / or electrical connection between the camera housing (4) and the support plate (3) is generated by a material bonding process.

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