Photosensitive assembly, optical image stabilization imaging device, welding method and visual inspection method

Abstract

The application discloses a photosensitive assembly, an optical anti-shake imaging device, a welding method and a visual detection method. The photosensitive assembly comprises a first circuit board, a second circuit board and a flexible circuit board. The second circuit board is in a frame shape with a through hole in the middle. The second circuit board is stacked on the bottom of the first circuit board. The lower surface of the first circuit board is provided with a plurality of first interconnection terminals. The lower surface of the second circuit board is provided with a plurality of second interconnection terminals. The first interconnection terminals and the second interconnection terminals are correspondingly arranged around the through hole. The inner side wall of the second circuit board has a plurality of transition zones corresponding to the first interconnection terminals and the second interconnection terminals. In the height direction, the projection of the transition zone is located between the projection areas of the second interconnection terminals and the first interconnection terminals. The two groups of interconnection terminals are electrically connected through the conductive connecting material bridged by the transition zone. The connection between the first circuit board and the second circuit board is exposed through the through hole. One end of the flexible circuit board is connected to the outer circumferential side of the second circuit board.

Description

Technical Field

[0001] This application relates to the field of optical imaging technology, and more specifically, to a photosensitive component, an optical image stabilization imaging device, a welding method, and a visual inspection method. Background Technology

[0002] Camera modules typically integrate focus drive components and image stabilization drive components. Focusing is achieved by driving the lens assembly to move along the optical axis, while image stabilization is achieved by driving the image sensor to move in a plane perpendicular to the optical axis. In some implementations, to reduce the lateral size of the camera module, the image sensor includes two stacked circuit boards. These two circuit boards need to be electrically connected via soldering, and the quality of the soldering directly affects the electrical performance and reliability of the camera module.

[0003] However, the soldering position of the two circuit boards is usually located in the sandwich area between the lower surface of the upper circuit board and the upper surface of the lower circuit board. This soldering method is prone to soldering defects such as cold solder joints and missing solder joints, which cannot be detected in time, resulting in a decrease in product yield and reliability. Summary of the Invention

[0004] One objective of this application is to provide a photosensitive component to solve the problem that the solder joints are completely obscured after two circuit boards are bonded together, making it impossible to directly observe and detect the soldering quality.

[0005] Another objective of this application is to provide a method for welding photosensitive components.

[0006] The third objective of this application is to provide a visual inspection method for photosensitive components, used to detect the connection between two circuit boards.

[0007] To achieve the above objectives, the technical solution adopted in this application is as follows: a photosensitive component, comprising a first circuit board, a second circuit board, and a flexible circuit board: the second circuit board is a frame-shaped structure with a through hole in the middle, the second circuit board is stacked at the bottom of the first circuit board, wherein the lower surface of the first circuit board is provided with a plurality of first interconnect terminals, the lower surface of the second circuit board is provided with a plurality of second interconnect terminals, the first interconnect terminals and the second interconnect terminals are arranged correspondingly around the through hole, the inner sidewall of the second circuit board has a plurality of transition areas corresponding to the first interconnect terminals and the second interconnect terminals; along the height direction, the projection of the transition area is located between the projection areas of the second interconnect terminals and the first interconnect terminals, the second interconnect terminals and the first interconnect terminals are electrically connected through a conductive connection material bridged by the transition area, and the connection between the first circuit board and the second circuit board is exposed through the through hole; one end of the flexible circuit board is connected to the outer periphery of the second circuit board.

[0008] As a preferred embodiment, the transition region is a vertical surface, a beveled surface, a convex arc surface, or a concave arc surface, and the conductive connecting material covers at least a portion of the transition region.

[0009] As another preferred embodiment, the first circuit board includes a downwardly projecting protrusion that is adapted to the through hole, at least a portion of the protrusion being accommodated in the through hole, and the first interconnecting terminal being disposed at the edge of the lower surface of the protrusion.

[0010] More preferably, the second interconnecting terminals are distributed along the first inner side and the second inner side opposite to each other on the second circuit board, and one end of the flexible circuit board is connected to the outer side of the second circuit board opposite to the first inner side and the second inner side.

[0011] More preferably, the conductive connecting material covers an area of ​​not less than half the surface area of ​​the first interconnect terminal on the first interconnect terminal, and covers an area of ​​not less than one-third the surface area of ​​the second interconnect terminal on the second interconnect terminal. The conductive connecting material is continuously distributed in the transition region and continuously connects the first interconnect terminal and the second interconnect terminal along the height direction.

[0012] More preferably, the outer perimeter of the second circuit board is smaller than the outer perimeter of the first circuit board.

[0013] This application also provides an optical image stabilization imaging device, which defines an optical axis and includes a fixed part and a movable part. The movable part is provided with the aforementioned photosensitive component, wherein the first circuit board is disposed on the movable part, and the other end of the flexible circuit board is connected to the fixed part.

[0014] More preferably, the fixing part includes a lens assembly, and the photosensitive component translates relative to the lens assembly in a plane perpendicular to the optical axis.

[0015] Further preferably, the flexible circuit board includes a U-shaped outer frame and four curved connecting portions located within the U-shaped outer frame. One end of each curved connecting portion is connected to the second circuit board, and the other end of each curved connecting portion is connected to the U-shaped outer frame. The U-shaped outer frame is fixedly connected to the fixing portion, and the four curved connecting portions are arranged circumferentially around the second circuit board.

[0016] More preferably, the fixed part includes a base, the movable part includes a support structure and a camera module, the camera module is disposed in the support structure, the camera module includes a lens assembly and the photosensitive assembly, and the support structure drives the camera module to rotate relative to the base.

[0017] Further preferably, the flexible circuit board includes a U-shaped outer frame and two curved connecting portions located within the U-shaped outer frame. A reinforcing member is attached to the bottom of the U-shaped outer frame, and the two curved connecting portions are located on opposite sides of the through hole.

[0018] Further preferably, the base also includes a magnetic suction assembly, which includes a first magnetic suction element and a second magnetic suction element. One of the first magnetic suction element and the second magnetic suction element is disposed on the lower surface of the first circuit board and corresponds to the through hole, while the other is disposed on the base.

[0019] This application also provides a welding method for a photosensitive component, the welding method comprising: S11, providing a first circuit board and a second circuit board, the second circuit board being a frame-shaped structure with a through hole in the middle and stacked on the bottom of the first circuit board, the lower surface of the first circuit board having a plurality of first interconnect terminals, the lower surface of the second circuit board having a plurality of second interconnect terminals, the first interconnect terminals and the second interconnect terminals being arranged correspondingly around the through hole, and the inner sidewall of the second circuit board having a plurality of transition areas corresponding to the first interconnect terminals and the second interconnect terminals; S12, coating the first interconnect terminals and / or the second interconnect terminals with a conductive connecting material, the first interconnect terminals, the transition areas and the second interconnect terminals forming a bridging path for the conductive connecting material to flow; S13, using a heating process to bridge the first interconnect terminals, the transition areas and the second interconnect terminals with the conductive connecting material, after the conductive connecting material is cured, the first circuit board and the second circuit board are fixed to each other and an electrical connection is achieved.

[0020] More preferably, the conductive connecting material is solder or conductive adhesive.

[0021] Further preferably, in step S12, the height difference n between the first interconnect terminal and the second interconnect terminal is less than n1, the conductive connection material is coated on the first interconnect terminal, and the thickness of the conductive connection material is not less than half of the height difference n; wherein, n1 is a preset first height difference threshold.

[0022] Further preferably, the conductive connection material includes solder balls and solder paste. When the height difference n between the first interconnect terminal and the second interconnect terminal satisfies n1≤n≤n2, the solder paste is applied to the second interconnect terminal, and the solder balls are pre-embedded on the surface of the second interconnect terminal; wherein, n1 is a preset first height difference threshold, n2 is a second height difference threshold, and n1<n2.

[0023] Further preferably, the conductive connection material is solder, and when the height difference n between the first interconnect terminal and the second interconnect terminal satisfies n1≤n≤n2, the conductive connection material is coated on both the first interconnect terminal and the second interconnect terminal; wherein, n1 is a preset first height difference threshold, n2 is a second height difference threshold, and n1<n2.

[0024] More preferably, when the conductive connection material is conductive adhesive, the conductive adhesive is coated on the first interconnect terminal and / or the second interconnect terminal, and the amount of conductive adhesive coated is sufficient to fill the gap between the first interconnect terminal and the second interconnect terminal.

[0025] This application also provides a visual inspection method for a photosensitive component, used to detect the connection between a first circuit board and a second circuit board of the photosensitive component, comprising: S21, acquiring images of the first circuit board and the second circuit board after electrical connection is completed to obtain a connection area image, wherein the connection area image includes at least a frontal image acquired along the height direction of the photosensitive component and a side image acquired along the direction perpendicular to the height direction; S22, acquiring feature information based on the frontal image and the side image, wherein the feature information is used to provide feedback on the electrical connection between the first circuit board and the second circuit board; wherein the feature information includes at least one of the following: the position of the first interconnect terminal, the outline shape of the first interconnect terminal, the position of the second interconnect terminal, the outline shape of the second interconnect terminal, the position of the conductive connecting material, and the outline shape of the conductive connecting material; S23, determining the connection between the first circuit board and the second circuit board based on the feature information.

[0026] Further preferably, step S23 includes: determining the coverage between the conductive connection material, the first interconnect terminal, and the second interconnect terminal based on the feature information; and determining that the connection is qualified if the coverage meets preset conditions.

[0027] Further preferably, the preset conditions include: a) in the frontal image, the conductive connecting material transitions uniformly between the first interconnect terminal and the second interconnect terminal, and the conductive connecting material covers at least half of the first interconnect terminal and at least one-third of the second interconnect terminal; b) in the side image, the conductive connecting material uniformly covers the transition area, and continuously covers the first interconnect terminal and the second interconnect terminal in the height direction without any breaks in the middle.

[0028] Compared with the prior art, the beneficial effects of this application are as follows: (1) The second circuit board is configured as a frame structure with through holes and is stacked on the bottom of the first circuit board. The soldering position between the first circuit board and the second circuit board is fully exposed through the through holes. This allows operators or automated vision inspection equipment to directly observe the solder joint status, promptly detect defects such as cold solder joints, missing solder joints, and insufficient solder climb, and perform local rework without disassembling the overall module, significantly reducing manufacturing and maintenance costs; (2) The first interconnect terminal is located on the lower surface of the first circuit board, and the second interconnect terminal is located on the upper surface of the second circuit board. The two are arranged in parallel and form a transition area through the sidewall of the through hole. The projection of the transition area along the optical axis is defined to be located between the projection areas of the two interconnect terminals, thereby establishing a defined and geometrically continuous bridging path between the two horizontally arranged interconnect terminals. The conductive connection material flows along the transition area, from the upper second interconnect terminal through the transition area to the lower first interconnect terminal, forming a smooth Z-shaped connection. This makes the flow of the conductive connection material more controllable and the filling more complete, thereby significantly reducing the risk of poor soldering and broken solder joints, and improving the mechanical strength of the solder joints and the long-term reliability of the electrical connection. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the photosensitive component provided in this application, with the reinforcing member removed.

[0030] Figure 2 for Figure 1 A magnified view of region A in the middle.

[0031] Figure 3 This is a schematic diagram of the second circuit board.

[0032] Figure 4 This is a schematic diagram of the structure of the first circuit board.

[0033] Figure 5 This is a schematic diagram of the structure of the first embodiment of the transition zone.

[0034] Figure 6 This is a schematic diagram of the structure of the second embodiment of the transition zone.

[0035] Figure 7 This is a schematic diagram of the third embodiment of the transition zone.

[0036] Figure 8 This is a schematic diagram of the fourth embodiment of the transition zone.

[0037] Figure 9 This is a schematic diagram of the structure of an optical image stabilization imaging device implemented as an image stabilization camera module.

[0038] Figure 10 for Figure 9 A magnified view of region B in the middle.

[0039] Figure 11 A schematic diagram of the image sensor component in a camera module designed for image stabilization.

[0040] Figure 12 This is a schematic diagram of an optical image stabilization imaging device implemented as a gimbal.

[0041] Figure 13 This is a schematic diagram of the photosensitive component of the gimbal.

[0042] Figure 14 This is a cross-sectional schematic diagram of the gimbal.

[0043] Figure 15 This is a schematic diagram showing that the connection is acceptable in a frontal shot image.

[0044] Figure 16 This is the first schematic diagram showing an unqualified connection in a frontal shot image.

[0045] Figure 17 This is a second schematic diagram showing an unqualified connection in a frontal shot image.

[0046] Figure 18 This is a third schematic diagram showing an unqualified connection in a frontal shot image.

[0047] Figure 19 This is a schematic diagram showing that the connection is acceptable in the side-view image.

[0048] Figure 20 This is a first schematic diagram showing a non-compliant connection in a side-view image.

[0049] Figure 21 This is a second schematic diagram showing an unqualified connection in a side-view image.

[0050] In the figure: 1. Fixing part; 10. Base; 11. Magnetic suction assembly; 111. First magnetic suction element; 112. Second magnetic suction element; 2. Movable part; 20. Camera module; 21. Photosensitive component; 211. First circuit board; 2111. First interconnecting terminal; 2112. Protrusion; 212. Second circuit board; 2121. Through hole; 2122. Second interconnecting terminal; 2123. Transition area; 2124. First inner side; 2125. Second inner side; 2126. First outer side; 2127. Second outer side; 23. Flexible circuit board; 231. U-shaped outer frame; 232. Bending connection part; 233. Reinforcing member; 234. Connector; 30. Support structure; 40. Drive assembly; 41. Drive coil; 42. Drive magnet; 51. First ball; 52. Ball groove. Detailed Implementation

[0051] The present application will be further described below with reference to specific embodiments. It should be noted that, without conflict, the various embodiments or technical features described below can be arbitrarily combined to form new embodiments.

[0052] In the description of this application, it should be noted that the terms "center", "lateral", "longitudinal", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc., which indicate the orientation and positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and should not be construed as limiting the specific protection scope of this application.

[0053] It should be noted that the terms "first," "second," etc., in the specification and claims of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence.

[0054] The terms “comprising” and “having”, and any variations thereof, in the specification and claims of this application are intended to cover non-exclusive inclusion, for example, a process, method, system, product, or device that includes a series of steps or units is not necessarily limited to those steps or units that are explicitly listed, but may include other steps or units that are not explicitly listed or that are inherent to such process, method, product, or device.

[0055] In the accompanying drawings of this application, the X-axis, Y-axis, and Z-axis are coordinate axes of a spatial rectangular coordinate system. Definitions: The length direction of the photosensitive element is parallel to the X-axis, the width direction of the photosensitive element is parallel to the Y-axis, and the height direction of the photosensitive element and the optical axis direction defined by the optical image stabilization imaging device are both parallel to the Z-axis. It is understood that this coordinate system setting can be flexibly adjusted according to actual needs and is not limited herein.

[0056] like Figure 1 As shown, this application provides a photosensitive component 21, which is used to receive light and convert it into an electrical signal.

[0057] The photosensitive component 21 includes a first circuit board 211, a second circuit board 212, and a flexible circuit board 23. The second circuit board 212 is a frame-shaped structure with a through hole 2121 in the middle. The second circuit board 212 is stacked on the bottom of the first circuit board 211. The lower surface of the first circuit board 211 is provided with a plurality of first interconnect terminals 2111, and the lower surface of the second circuit board 212 is provided with a plurality of second interconnect terminals 2122. The first interconnect terminals 2111 and the second interconnect terminals 2122 are arranged correspondingly around the through hole 2121. The inner wall of the second circuit board 212 has… There are multiple transition regions 2123 corresponding to the first interconnect terminal 2111 and the second interconnect terminal 2122; along the Z-axis direction, the projection of the transition region 2123 is located between the projection areas of the second interconnect terminal 2122 and the first interconnect terminal 2111, and the second interconnect terminal 2122 and the first interconnect terminal 2111 are electrically connected through the conductive connection material bridged by the transition region 2123, and the connection between the first circuit board 211 and the second circuit board 212 is exposed through the through hole 2121; one end of the flexible circuit board 23 is connected to the outer periphery of the second circuit board 212.

[0058] Specifically, such as Figure 1 as well as Figure 2 As shown, the transition area 2123 formed by the frame structure and sidewalls of the second circuit board 212 enables a three-dimensional bridge between the first interconnect terminal 2111 and the second interconnect terminal 2122, and achieves electrical connection through conductive connection material. This significantly increases the electrical contact area and mechanical bonding area, thereby reducing contact resistance, improving current carrying capacity, and enhancing the tensile, shear and impact resistance of the solder joint.

[0059] In existing technologies, the soldering points between the upper and lower circuit boards are located on the lower surface of the upper circuit board and the upper surface of the lower circuit board. After soldering, the connection cannot be directly observed, making it prone to incomplete or missing solder joints, leading to reduced product yield and reliability. Therefore, as... Figure 3As shown, this application optimizes the structure of the second circuit board 212 by providing a through hole 2121 in its center. The connection between the first circuit board 211 and the second circuit board 212 is exposed to the outside through the through hole 2121 without any obstruction. This allows the inspection equipment to directly perform optical imaging on the solder joints from the through hole 2121. The exposed soldering position can simultaneously acquire: a frontal image along the Z-axis and a side image perpendicular to the Z-axis, to observe the coverage area and uniformity of the conductive connection material on each interconnecting terminal, as well as the continuity of the conductive connection material along the transition region 2123 and whether there are any breaks. Moreover, image acquisition can be completed using a common industrial camera, and the quality of the solder joints can be quickly judged with the help of a visual inspection algorithm, without the need for expensive X-ray equipment. At the same time, optical inspection is not a destructive inspection, and each photosensitive component 21 can be fully inspected to ensure the yield of the photosensitive component 21.

[0060] It is understood that the "connection status" described in this application includes both the state before and after electrical connection. The connection status before electrical connection may include: whether the first circuit board 211 and the second circuit board 212 are aligned, whether the first interconnect terminal 2111 and the second interconnect terminal 2122 are aligned, etc.; the connection status after electrical connection may include: whether the conductive connection material is insufficient, whether there is a break in the connection, whether the transition area 2123 is evenly covered, etc. Furthermore, the frontal image along the Z-axis can be taken from above or below, as long as the obtained frontal image can clearly express the connection status from that perspective; the shooting direction and angle are not limited here.

[0061] Furthermore, the through-hole 2121 allows the soldering position to be fully exposed to the air, which is conducive to the dissipation of heat during the soldering process and reduces the risk of circuit board warping or thermal stress caused by heat accumulation.

[0062] Furthermore, after a through hole 2121 is provided in the middle of the second circuit board 212, the first interconnect terminal 2111 and the second interconnect terminal 2122 do not need to be vertically aligned. This reduces the alignment accuracy requirements of the assembly equipment, reduces soldering defects caused by alignment deviations, and helps to improve production yield.

[0063] In some embodiments, the first circuit board 211 includes a centrally located and downwardly projecting protrusion 2112, the protrusion 2112 being adapted to a through hole 2121, at least a portion of the protrusion 2112 being accommodated in the through hole 2121, and a first interconnect terminal 2111 being disposed at the edge of the lower surface of the protrusion 2112.

[0064] Specifically, such as Figure 3 and Figure 4As shown, the protrusion 2112 is located in the center of the first circuit board 211 and protrudes downward. The shape and size of the protrusion 2112 are adapted to the through hole 2121 of the second circuit board 212, both being rectangular, and the protrusion 2112 is at least partially accommodated within the through hole 2121. The peripheral edge of the protrusion 2112 is provided with a plurality of first interconnect terminals 2111, and the peripheral edge of the through hole 2121 is provided with a plurality of second interconnect terminals 2122, with each first interconnect terminal 2111 corresponding to a second interconnect terminal 2122.

[0065] Furthermore, the protrusion 2112 protrudes from the body of the first circuit board 211 and is at least partially accommodated within the through hole 2121. This not only reduces the overall height of the two circuit boards stacked together, promoting the miniaturization of the module, but also reduces the height difference between the first interconnect terminal 2111 and the second interconnect terminal 2122, effectively avoiding the risk of connection breakage due to excessive height difference and significantly improving connection reliability.

[0066] Specifically, the first circuit board 211 is a multilayer circuit board, wherein the number of layers at the center of the first circuit board 211 is greater than the number of layers at the edge, and the protrusion 2112 is formed by the difference in the number of layers, and the processing method is simple and reliable.

[0067] The transition region 2123 connects the first interconnect terminal 2111 and the second interconnect terminal 2122, and is used to guide the conductive connection material to smoothly transition between the two interconnect terminals. The specific shape of the transition region 2123 has an important influence on the flow characteristics and stress distribution of the conductive connection material.

[0068] In some embodiments, the transition region 2123 is a vertical surface, a beveled surface, a convex arc surface, or a concave arc surface, and the conductive connection material covers at least a portion of the transition region 2123.

[0069] In one implementation, such as Figure 5 As shown, the transition region 2123 is a vertical plane, perpendicular to the first interconnect terminal 2111 and the second interconnect terminal 2122. This method is simple to process, suitable for conventional processes such as stamping or milling, and has a low cost.

[0070] In some optional embodiments, such as Figure 6 As shown, the transition region 2123 is a beveled surface with an acute angle between it and the optical axis. The beveled surface can guide the conductive connection material to flow better from the first interconnect terminal 2111 to the second interconnect terminal 2122, while reducing stress concentration at the right angle, thereby reducing the risk of breakage due to drops or vibrations.

[0071] In some optional embodiments, such as Figure 7 and Figure 8As shown, the transition region 2123 can also be an upwardly convex arc surface or a downwardly concave arc surface. The arc surface forms a smooth transition at the corner, without sharp corners or abrupt changes, which can guide the smooth flow of conductive connection material, make wetting more sufficient, reduce voids and cold welding phenomena, and effectively avoid stress concentration.

[0072] In summary, the four transition region shapes 2123 provided in this application offer flexible options in terms of processing cost, fluidity of conductive connection materials, and stress distribution, enabling this solution to be adapted to products with different reliability requirements and cost budgets.

[0073] In some embodiments, the second interconnecting terminals 2122 are distributed along the first inner side 2124 and the second inner side 2125 opposite to the second circuit board 212, and one end of the flexible circuit board 23 is connected to the outer side of the second circuit board 212 opposite to the first inner side 2124 and the second inner side 2125.

[0074] Specifically, such as Figure 3 As shown, the second circuit board 212 has a first inner side 2124 and a second inner side 2125 that are arranged opposite to each other. The second interconnection terminal 2122 located on these two inner sides is electrically connected to the first interconnection terminal 2111 on the corresponding side.

[0075] In addition, such as Figure 3 As shown, the flexible circuit board 23 extends from the outer periphery of the second circuit board 212. The outer periphery of the second circuit board 212 includes a first outer side 2126 and a second outer side 2127. The first outer side 2126 is on the same side as the first inner side 2124, and the second outer side 2127 is on the same side as the second inner side 2125. The flexible circuit board 23 extends from the first outer side 2126 and the second outer side 2127, and is led out through multiple bends, achieving a flexible signal transmission path layout.

[0076] In some embodiments, the conductive connecting material covers an area on the first interconnect terminal 2111 that is not less than half of the surface area of ​​the first interconnect terminal 2111, and covers an area on the second interconnect terminal 2122 that is not less than one-third of the surface area of ​​the second interconnect terminal 2122. The conductive connecting material is continuously distributed on the transition region 2123 and is continuously connected to the first interconnect terminal 2111 and the second interconnect terminal 2122 along the optical axis direction.

[0077] Specifically, this application provides a quantitative standard for automated detection of qualified connections by quantifying the coverage area of ​​the conductive connection material on the first interconnect terminal 2111 and the second interconnect terminal 2122, and by limiting its continuous distribution on the transition region 2123, replacing traditional manual visual inspection; at the same time, sufficient coverage area and continuous conductive path ensure the mechanical strength and electrical integrity of the connection.

[0078] This application also provides an optical image stabilization imaging device. The optical image stabilization imaging device defines an optical axis and includes a fixed part 1 and a movable part 2. The movable part 2 is provided with a photosensitive component 21. A first circuit board 211 is disposed on the movable part 2, and the other end of a flexible circuit board 23 is connected to the fixed part 1.

[0079] It is understood that the optical image stabilization imaging device provided in this application, as a general concept, has a wide range of applications. This device can be implemented as a standalone image stabilization camera module, used in portable devices such as mobile phones and vehicle cameras, achieving optical image stabilization by driving the photosensitive component to translate relative to the lens component; or it can be implemented as a gimbal, used in scenarios such as handheld stabilizers and drone aerial photography, achieving image stabilization by driving the support structure to rotate the entire image stabilization camera module. For ease of understanding, these two implementation methods will be described in detail below.

[0080] In one implementation, such as Figure 9 As shown, the fixing part 1 includes a lens assembly 24, and the photosensitive component 21 translates relative to the lens assembly 24 in a plane perpendicular to the optical axis to achieve optical image stabilization.

[0081] When the device is implemented as a camera stabilization module, such as Figure 10 As shown, the image stabilization camera module also includes a drive assembly 40, which includes a drive coil 41 and a drive magnet 42 arranged opposite each other along the Z-axis. The drive magnet 42 is disposed on the lower surface of the fixed part 1, and the drive coil 41 is disposed on the upper surface of the movable part 2. The drive coil 41 and the drive magnet 42 cooperate to generate a Lorentz force, driving the movable part 2 to move relative to the fixed part 1. Simultaneously, a magnetic attraction part is disposed below the movable part 2, and the magnetic attraction part and the drive magnet 42 are aligned along the Z-axis, generating a magnetic attraction force between them. A first ball bearing 51 is provided between the fixed part 1 and the movable part 2. Based on this magnetic attraction force, the movable part 2 and the fixed part 1 clamp the first ball bearing 51 along the Z-axis, thereby achieving smooth movement of the movable part 2 relative to the fixed part 1 and reducing the frictional resistance between them.

[0082] Furthermore, such as Figure 10 As shown, the upper surface of the movable part 2 is provided with a ball groove 52 for embedding the first ball 51. The ball groove 52 is hemispherical to limit the setting position of the first ball 51.

[0083] Furthermore, such as Figure 1 as well as Figure 11 As shown, the flexible circuit board 23 includes a U-shaped outer frame 231 and four curved connecting parts 232 located within the U-shaped outer frame 231. A reinforcing member 233 is attached to the bottom of the U-shaped outer frame 231, and the four curved connecting parts 232 are arranged circumferentially around the through hole 2121.

[0084] It is understandable that the reinforcing member 233 is a U-shaped steel sheet used to structurally reinforce and support the flexible circuit board 23, thereby further enhancing the overall structural support and reducing the risk of open circuits caused by bending and deformation of the flexible circuit board 23 during use. In addition, a connector 234 is provided on one outer side of the U-shaped outer frame 231 for connecting to external circuits.

[0085] In another implementation, such as Figure 12 As shown, the fixed part 1 includes a base 10, and the movable part 2 includes a support structure 30 and a camera module 20. The camera module 20 is disposed in the support structure 30 and includes a lens assembly 24 and a photosensitive assembly 21. During the image stabilization process, the lens assembly 24 and the photosensitive assembly 21 are relatively fixed, and the support structure 30 drives the entire camera module 20 to rotate relative to the base 10 to resist external shaking and achieve optical image stabilization.

[0086] In some embodiments, such as Figure 13 As shown, the flexible circuit board 23 includes a U-shaped outer frame 231 and two bent connecting parts 232 located inside the U-shaped outer frame 231. The two bent connecting parts 232 are located on the opposite outer sides of the through hole 2121. The bottom of the U-shaped outer frame 231 is also fitted with a reinforcing member 233, which is also a U-shaped steel sheet. This can strengthen the flexible circuit board 23, improve its bending resistance, and reduce the risk of circuit breakage.

[0087] To prevent the multiple curved connecting parts 232 of the flexible circuit board 23 from pulling against each other during rotation, the flexible circuit board 23 adopts an asymmetrical design with only two curved connecting parts 232. Each curved connecting part 232 extends along two adjacent outer edges of the through hole 2121. This arrangement can support a longer curved part length, thereby providing the camera module 20 with greater rotational freedom and ensuring smooth image stabilization.

[0088] In the gimbal stabilization implementation, the camera module 20 achieves stabilization by rotating around two axes. Therefore, a certain amount of space needs to be reserved in all directions (up, down, left, and right) of the camera module 20 to meet the rotation requirements. To prevent the camera module 20 from shifting upwards during stabilization, a magnetic suction component 11 is provided below the camera module 20 to provide a downward suction force and prevent it from shifting upwards.

[0089] In some embodiments, the base 10 further includes a magnetic suction assembly 11, which includes a first magnetic suction member 111 and a second magnetic suction member 112. One of the first magnetic suction member 111 and the second magnetic suction member 112 is disposed on the lower surface of the first circuit board 211 and corresponds to the through hole 2121, while the other is disposed on the base 10.

[0090] Specifically, such as Figure 13 as well as Figure 14 As shown, the first magnetic attractor 111 is located on the base 10, and the second magnetic attractor 112 is located on the lower surface of the first circuit board 211. The first magnetic attractor 111 and the second magnetic attractor 112 are directly opposite each other through the through hole 2121, and thus attract each other. The magnetic attractor assembly 11 can be two magnetic pieces, both of which are magnetic, or it can be a combination of a magnetic piece and a attracted component. The second magnetic attractor 112 is disposed on the lower surface of the first circuit board 211 and at a position corresponding to the through hole 2121. The space provided by the through hole 2121 is used to accommodate the magnetic attractor assembly 11, without increasing the overall size of the camera module 20.

[0091] In this embodiment, the difference in outer peripheral dimensions between the first circuit board 211 and the second circuit board 212 is small. If the difference in their outer peripheral dimensions is too large, positional interference may easily occur between the flexible circuit board 23 and the first circuit board 211 during rotation, affecting the smoothness of the stabilization motion. Therefore, in gimbal stabilization scenarios, the outer peripheral dimensions of the first circuit board 211 and the second circuit board 212 can be set to be similar, or equal, or even the outer peripheral dimension of the second circuit board 212 can be larger than that of the first circuit board 211 to avoid interference during rotation.

[0092] Furthermore, such as Figure 14 As shown, the gimbal also includes a drive assembly 40, which comprises a drive coil 41 and a drive magnet 42. One of the drive magnet 42 and the drive coil 41 is mounted on the base 10, and the other is mounted on the support structure 30. When the drive coil 41 is energized, its magnetic field interacts with the magnetic field of the drive magnet 42, generating an electromagnetic driving force that drives the support structure 30 to rotate the camera module 20 relative to the base 10, thus achieving image stabilization compensation.

[0093] Preferably, the driving magnet 42 can also be disposed on the support structure 30, and the driving coil 41 can be disposed on the base 10, which is not limited here.

[0094] Furthermore, the drive assembly 40 includes two drive coils 41 and two drive magnets 42, each drive magnet 42 corresponding to one drive coil 41. The two sets of drive assemblies 40 are respectively disposed on two adjacent sides of the support structure 30.

[0095] This application also provides a welding method for a photosensitive component 21, the welding method comprising: S11. A first circuit board 211 and a second circuit board 212 are provided. The second circuit board 212 is a frame structure with a through hole 2121 in the middle and is stacked on the bottom of the first circuit board 211. The lower surface of the first circuit board 211 is provided with a plurality of first interconnect terminals 2111, and the lower surface of the second circuit board 212 is provided with a plurality of second interconnect terminals 2122. The first interconnect terminals 2111 and the second interconnect terminals 2122 are arranged around the through hole 2121. The inner sidewall of the second circuit board 212 has a plurality of transition areas 2123 corresponding to the first interconnect terminals 2111 and the second interconnect terminals 2122. S12. A conductive connection material is coated on the first interconnect terminal 2111 and / or the second interconnect terminal 2122, and the first interconnect terminal 2111, the transition region 2123 and the second interconnect terminal 2122 form a bridging path for the conductive connection material to flow. S13. Through a heating process, the conductive connecting material bridges the first interconnecting terminal 2111, the transition area 2123, and the second interconnecting terminal 2122. After the conductive connecting material is cured, the first circuit board 211 and the second circuit board 212 are fixed to each other and an electrical connection is achieved.

[0096] It is understandable that, such as Figure 1 As shown, the first interconnect terminal 2111 and the second interconnect terminal 2122 are staggered in the XY plane. By aligning and stacking the first circuit board 211 and the second circuit board 212, the first interconnect terminal 2111, the transition region 2123, and the second interconnect terminal 2122 form a three-dimensional bridging path along the Z-axis, providing a clear flow guide for the conductive connection material. After heating, the conductive connection material flows along this path and simultaneously adheres to the first interconnect terminal 2111, the transition region 2123, and the second interconnect terminal 2122. After curing, a three-dimensional encapsulated connection structure is formed, allowing the conductive connection material to contact three surfaces, significantly increasing the electrical contact area and reducing the contact resistance. At the same time, this non-linear connection path can disperse the stress generated by thermal cycling or mechanical impact to multiple interfaces, thereby reducing the risk of interface cracking due to thermal expansion coefficient mismatch.

[0097] In some embodiments, the conductive connecting material is solder or conductive adhesive, and there is no limitation herein.

[0098] It should be noted that the specific type of conductive connection material and the height difference between the first interconnect terminal 2111 and the second interconnect terminal 2122 will have a substantial impact on the welding process steps. Therefore, the following will explain them separately according to different situations.

[0099] When the height difference n between the first interconnect terminal 2111 and the second interconnect terminal 2122 is less than n1, a conductive connection material is coated on the first interconnect terminal 2111, and the thickness of the conductive connection material is not less than half of the height difference n, so as to achieve pre-fitting and positioning between the first circuit board 211 and the second circuit board 212; wherein, n1 is a preset first height difference threshold.

[0100] For example, n1 is 0.3mm. During soldering, conductive connection material is only coated on the first interconnect terminal 2111, and the thickness of the conductive connection material is not less than half of the height difference n. The second interconnect terminal 2122 is not coated with conductive connection material. After the first interconnect terminal 2111 and the second interconnect terminal 2122 are precisely aligned, they are placed in a reflow oven and heated according to the reflow soldering temperature zone curve. During the heating process, the conductive connection material melts. Utilizing the capillary force and surface tension of the liquid conductive connection material, the first interconnect terminal 2111, the second interconnect terminal 2122, and the transition zone 2123 are automatically bridged, filling the height difference. After cooling, a stable connection bridge is formed, and the soldering is completed.

[0101] In this implementation, a conductive connecting material is coated on the first interconnect terminal 2111, which can bond the first circuit board 211 and the second circuit board 212 together, avoiding positional displacement between the first circuit board 211 and the second circuit board 212 during the soldering process.

[0102] When the conductive connection material is solder, and the height difference n between the first interconnect terminal 2111 and the second interconnect terminal 2122 satisfies n1≤n≤n2, the conductive connection material is coated on the second interconnect terminal 2122, and solder balls are pre-planted on the surface of the second interconnect terminal 2122.

[0103] It is understood that n1 is a preset first height difference threshold, and n1 is 0.3mm. When the height difference n between the first interconnect terminal 2111 and the second interconnect terminal 2122 is between 0.3mm and 0.8mm, solder is applied only to the second interconnect terminal 2122 during soldering, with a solder thickness of 0.15mm to 0.2mm, while the first interconnect terminal 2111 is not coated with solder. To compensate for the height difference n between the two interconnect terminals, small solder balls with a diameter of 0.2mm to 0.3mm are pre-planted on the surface of the second interconnect terminal 2122. After the first circuit board 211 and the second circuit board 212 are precisely aligned using a vacuum adsorption fixture, they are sent into a reflow oven. The reflow soldering temperature zone curve is optimized, and the melting and holding time is extended to allow the solder and solder balls to fully melt. Utilizing the surface tension and capillary force of the liquid solder, the first interconnect terminal 2111, the second interconnect terminal 2122, and the transition area 2123 are bridged, filling the height difference. After cooling, a full and continuous connection bridge is formed, completing the soldering.

[0104] In this example, the solder ball can be fixed in the center of the second interconnect terminal 2122 by solder, preventing the solder ball from shifting.

[0105] When the conductive connection material is solder, and the height difference n between the first interconnect terminal 2111 and the second interconnect terminal 2122 satisfies n1≤n≤n2, the conductive connection material is coated on both the first interconnect terminal 2111 and the second interconnect terminal 2122; wherein n1 is a preset first height difference threshold, n2 is a second height difference threshold, and n1<n2.

[0106] Specifically, during soldering, the first interconnect terminal 2111 and the second interconnect terminal 2122 are coated with solder with a thickness of 0.15mm to 0.2mm. After the first circuit board 211 and the second circuit board 212 are precisely aligned by a vacuum adsorption fixture, they are sent into a reflow oven. The reflow soldering temperature zone curve is optimized and the melting and holding time is extended to allow the upper and lower layers of solder to fully melt. The surface tension and capillary force of the liquid solder are used to bridge the first interconnect terminal 2111, the second interconnect terminal 2122 and the transition area 2123, filling the height difference. After cooling, a full and continuous connecting bridge is formed, completing the soldering.

[0107] When the conductive connection material is conductive adhesive, conductive adhesive is applied to the first interconnect terminal 2111 and / or the second interconnect terminal 2122. The amount of conductive adhesive applied is sufficient to fill the gap between the first interconnect terminal 2111 and the second interconnect terminal 2122 to achieve electrical connection between the two circuit boards.

[0108] This application also provides a visual inspection method for a photosensitive component 21, used to detect the connection quality of the connection between the first circuit board 211 and the second circuit board 212 of the photosensitive component 21. The visual inspection method includes: S21. After the electrical connection is completed, image acquisition is performed on the first circuit board 211 and the second circuit board 212 to obtain the connection area image. The connection area image includes at least a frontal image acquired along the height direction of the photosensitive component 21 and a side image acquired along the direction perpendicular to the height. S22. Based on the frontal and side images, feature information is obtained. The feature information is used to provide feedback on the electrical connection between the first circuit board 211 and the second circuit board 212. The feature information includes at least one of the following: the position of the first interconnect terminal 2111, the outline shape of the first interconnect terminal 2111, the position of the second interconnect terminal 2122, the outline shape of the second interconnect terminal 2122, the position of the conductive connection material, and the outline shape of the conductive connection material. S23. Determine the connection status of the first circuit board 211 and the second circuit board 212 based on the feature information.

[0109] Specifically, the obtained images include orthographic images. Figures 15-18 The image shown is a top-down image, which is taken by the vision module above the two circuit boards at an angle perpendicular to the XY plane. The top-down image can reflect the connection status of the first circuit board 211 and the second circuit board 212 on the XY plane.

[0110] Further, step S23 includes: determining the coverage between the conductive connection material, the first interconnecting terminal 2111, and the second interconnecting terminal 2122 based on the feature information; and determining that the connection is qualified if the coverage meets the preset conditions.

[0111] For example, when acquiring feature information based on frontal and side images, if the position or outline shape of the conductive connection material is identified, it is determined that the connection between the first circuit board 211 and the second circuit board 212 in the photosensitive component 21 is unqualified.

[0112] Furthermore, the preset conditions include: a) In the positive image, the conductive connection material transitions uniformly between the first interconnect terminal 2111 and the second interconnect terminal 2122, and the conductive connection material covers at least half of the first interconnect terminal 2111 and at least one-third of the second interconnect terminal 2122; b) In the side view image, the conductive connecting material uniformly covers the transition area 2123 and continuously covers the first interconnect terminal 2111 and the second interconnect terminal 2122 in the height direction without any breaks in between.

[0113] Specifically, Figures 15-18 For some examples of overhead views, the two rectangles represent the first interconnect terminal 2111 and the second interconnect terminal 2122, respectively, and the lines represent the conductive connection material. This conductive connection material may have the following characteristics: Case 1: such as Figure 15 As shown, the conductive connection material transitions uniformly between the first interconnect terminal 2111 and the second interconnect terminal 2122, and the conductive connection material covers at least half of the second interconnect terminal 2122 and at least half of the first interconnect terminal 2111. Case 1 indicates that there are no issues such as cold solder joints or broken solder joints in the XY plane; therefore, this connection condition is marked as XY plane qualified.

[0114] It is understandable that during the welding process, if the conductive connecting material is applied to the first interconnect terminal 2111, and the area of ​​the conductive connecting material covering the second interconnect terminal 2122 is greater than 1 / 3 of the surface area of ​​the second interconnect terminal 2122, then the XY plane is considered acceptable. Similarly, during the welding process, if the conductive connecting material is applied to the second interconnect terminal 2122, and the area of ​​the conductive connecting material covering the first interconnect terminal 2111 is greater than 1 / 3 of the surface area of ​​the first interconnect terminal 2111, then the XY plane is considered acceptable.

[0115] Scenario 2: such as Figure 16 As shown, the conductive connecting material transitions uniformly between the first interconnect terminal 2111 and the second interconnect terminal 2122. However, the coverage area of ​​the conductive connecting material on the second interconnect terminal 2122 is too small. For example, the coverage area of ​​the conductive connecting material on the second interconnect terminal 2122 is less than 1 / 2 or 1 / 3 of the surface area of ​​the second interconnect terminal 2122. This can easily lead to poor soldering and solder joint breakage. Therefore, case 2 is marked as XY plane non-compliance.

[0116] Scenario 3: such as Figure 17 As shown, the conductive connecting material transitions evenly between the first interconnect terminal 2111 and the second interconnect terminal 2122. However, the coverage area of ​​the conductive connecting material on the first interconnect terminal 2111 is too small. If the coverage area of ​​the conductive connecting material on the first interconnect terminal 2111 is less than 1 / 3 of the surface area of ​​the first interconnect terminal 2111, there is a risk of poor soldering and solder joint breakage. Therefore, case 2 is marked as XY plane non-compliance.

[0117] It is understandable that, since the second interconnect terminal 2122 is located below the first interconnect terminal 2111 when the circuit board is assembled in the optical image stabilization imaging device, after the electrical connection is completed, the area of ​​the conductive connecting material covering the first interconnect terminal 2111 can be smaller than the area covering the second interconnect terminal 2122. This makes the center of gravity of the conductive connecting material lower, resulting in a more stable structure with stronger shock resistance and stress resistance.

[0118] Case 4: Figure 18 As shown, the conductive connecting material is not uniformly transitioned between the first interconnect terminal 2111 and the second interconnect terminal 2122. That is, the width of the middle part of the conductive connecting material is significantly smaller than the width of its two ends. There may be a break in the conductive connecting material between the two interconnect terminals. Therefore, case 4 is marked as unqualified.

[0119] It is understandable that the uniform transition of the conductive connecting material between the first interconnect terminal 2111 and the second interconnect terminal 2122 mentioned above means that the conductive connecting material covers the first interconnect terminal 2111 and the second interconnect terminal 2122, and the width of the conductive connecting material does not change significantly, and there is no situation where it becomes thinner in the middle.

[0120] For images taken from the side, such as Figures 19-21 As shown, the gray area represents the conductive connecting material, which may present the following situations: Case 1: such as Figure 19 As shown, the conductive connecting material uniformly covers the transition area 2123, and the conductive connecting material covers the first interconnect terminal 2111 and the second interconnect terminal 2122 in the Z-axis direction without any breaks in the middle, indicating that there is no case of poor soldering or solder breakage. Therefore, this situation is marked as qualified in the Z-direction.

[0121] Scenario 2: such as Figure 20 As shown, the conductive connecting material uniformly covers the transition area 2123, but the conductive connecting material does not cover the second interconnect terminal 2122 in the Z-axis direction, or the thickness and height of the solder covering the second interconnect terminal 2122 in the Z-axis direction are too small. The conductive connecting material is prone to breakage on the second interconnect terminal 2122. Therefore, case 2 is unqualified in the Z-direction.

[0122] Scenario 3: such as Figure 21 As shown, when the conductive connecting material covers the transition area 2123, there is a break in the Z-axis direction. Therefore, case 3 is unqualified in the Z-direction.

[0123] It is understandable that for a set of first interconnect terminals 2111 and second interconnect terminals 2122, electrical connection requirements must be met in both the XY plane and the Z-axis direction, i.e., marked as qualified in both the XY plane and the Z-axis direction. Therefore, the connection of a set of first interconnect terminals 2111 and second interconnect terminals 2122 must simultaneously meet these requirements. Figure 15 as well as Figure 19 Only the conditions shown are considered acceptable; all other combinations are considered unacceptable.

[0124] Furthermore, after visual inspection, the results of each group are marked. For unqualified results, the type of unqualified result also needs to be marked to facilitate rework and modification.

[0125] The basic principles, main features, and advantages of this application have been described above. Those skilled in the art should understand that this application is not limited to the above embodiments. The embodiments and descriptions in the specification are merely the principles of this application. Various changes and modifications can be made to this application without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claims. The scope of protection claimed by this application is defined by the appended claims and their equivalents.

Claims

1. A photosensitive component, characterized in that, Includes a first circuit board, a second circuit board, and a flexible circuit board: The second circuit board is a frame structure with a through hole in the middle. The second circuit board is stacked on the bottom of the first circuit board. The lower surface of the first circuit board is provided with a plurality of first interconnect terminals, and the lower surface of the second circuit board is provided with a plurality of second interconnect terminals. The first interconnect terminals and the second interconnect terminals are arranged around the through hole. The inner sidewall of the second circuit board has a plurality of transition areas corresponding to the first interconnect terminals and the second interconnect terminals. The first circuit board includes a downwardly protruding portion that is adapted to the through hole, at least a portion of the protruding portion being accommodated in the through hole, and the first interconnecting terminal being disposed on the edge of the lower surface of the protruding portion; Along the height direction, the projection of the transition area is located between the projection areas of the second interconnect terminal and the first interconnect terminal, such that the first interconnect terminal, the transition area and the second interconnect terminal form a three-dimensional bridging path along the height direction. The second interconnect terminal and the first interconnect terminal are electrically connected through the conductive connection material bridged by the transition area, and the connection between the first circuit board and the second circuit board is exposed through the through hole for visual inspection. One end of the flexible circuit board is connected to the outer periphery of the second circuit board.

2. The photosensitive component as described in claim 1, characterized in that, The transition region is a vertical surface, a beveled surface, a convex arc surface, or a concave arc surface, and the conductive connecting material covers at least a portion of the transition region.

3. The photosensitive component as described in claim 1, characterized in that, The second interconnecting terminals are distributed along the first inner side and the second inner side opposite to each other on the second circuit board, and one end of the flexible circuit board is connected to the outer side of the second circuit board opposite to the first inner side and the second inner side.

4. The photosensitive component as described in claim 1, characterized in that, The conductive connecting material covers an area of ​​not less than half the surface area of ​​the first interconnect terminal on the first interconnect terminal and a coverage area of ​​not less than one-third the surface area of ​​the second interconnect terminal on the second interconnect terminal. The conductive connecting material is continuously distributed in the transition region and continuously connects the first interconnect terminal and the second interconnect terminal along the height direction.

5. The photosensitive component as described in claim 1, characterized in that, The outer perimeter of the second circuit board is smaller than that of the first circuit board.

6. An optical image stabilization imaging device, characterized in that, The optical image stabilization imaging device defines an optical axis and includes a fixed part and a movable part. The movable part is provided with a photosensitive component as described in any one of claims 1-4, wherein the first circuit board is disposed on the movable part, and the other end of the flexible circuit board is connected to the fixed part.

7. The optical image stabilization imaging device as described in claim 6, characterized in that, The fixing part includes a lens assembly, and the photosensitive component translates relative to the lens assembly in a plane perpendicular to the optical axis.

8. The optical image stabilization imaging device as described in claim 7, characterized in that, The flexible circuit board includes a U-shaped outer frame and four curved connecting parts located within the U-shaped outer frame. One end of each curved connecting part is connected to the second circuit board, and the other end of each curved connecting part is connected to the U-shaped outer frame. The U-shaped outer frame is fixedly connected to the fixing part, and the four curved connecting parts are arranged circumferentially around the second circuit board.

9. The optical image stabilization imaging device as described in claim 6, characterized in that, The fixed part includes a base, and the movable part includes a support structure and a camera module. The camera module is disposed within the support structure and includes a lens assembly and a photosensitive assembly. The support structure drives the camera module to rotate relative to the base.

10. The optical image stabilization imaging device as described in claim 9, characterized in that, The flexible circuit board includes a U-shaped outer frame and two curved connecting parts located within the U-shaped outer frame. The two curved connecting parts are connected to the opposite inner sides of the second circuit board.

11. The optical image stabilization imaging device as described in claim 9, characterized in that, The base also includes a magnetic suction assembly, which includes a first magnetic suction element and a second magnetic suction element. One of the first magnetic suction element and the second magnetic suction element is disposed on the lower surface of the first circuit board and corresponds to the through hole, while the other is disposed on the base.

12. A method for welding a photosensitive component, characterized in that, The welding method includes: S11. A first circuit board and a second circuit board are provided. The second circuit board is a frame structure with a through hole in the middle and is stacked on the bottom of the first circuit board. The lower surface of the first circuit board is provided with a plurality of first interconnect terminals, and the lower surface of the second circuit board is provided with a plurality of second interconnect terminals. The first interconnect terminals and the second interconnect terminals are arranged correspondingly around the through hole. The inner sidewall of the second circuit board has a plurality of transition areas corresponding to the first interconnect terminals and the second interconnect terminals. The first interconnect terminals, the transition areas and the second interconnect terminals form a three-dimensional bridging path along the height direction. The first circuit board includes a downwardly protruding part. The protruding part is adapted to the through hole. At least a portion of the protruding part is accommodated in the through hole. The first interconnect terminal is disposed on the edge of the lower surface of the protruding part. S12. A conductive connection material is coated on the first interconnect terminal and / or the second interconnect terminal, wherein the first interconnect terminal, the transition region and the second interconnect terminal form a bridging path for the conductive connection material to flow. S13. Through a heating process, the conductive connection material is used to bridge the first interconnect terminal, the transition area, and the second interconnect terminal. After the conductive connection material is cured, the first circuit board and the second circuit board are fixed to each other and electrically connected. The connection between the first circuit board and the second circuit board is exposed through the through hole.

13. The welding method as described in claim 12, characterized in that, The conductive connecting material is solder or conductive adhesive.

14. The welding method as described in claim 12, characterized in that, In step S12, the height difference n between the first interconnect terminal and the second interconnect terminal is less than n1, the conductive connection material is coated on the first interconnect terminal, and the thickness of the conductive connection material is not less than half of the height difference n; Where n1 is the preset first height difference threshold.

15. The welding method as described in claim 12, characterized in that, The conductive connection material includes solder balls and solder paste. When the height difference n between the first interconnect terminal and the second interconnect terminal satisfies n1≤n≤n2, the solder paste is applied to the second interconnect terminal, and the solder balls are pre-embedded on the surface of the second interconnect terminal. Wherein, n1 is the preset first height difference threshold, n2 is the second height difference threshold, and n1 < n2.

16. The welding method as described in claim 12, characterized in that, The conductive connection material is solder. When the height difference n between the first interconnect terminal and the second interconnect terminal satisfies n1≤n≤n2, the conductive connection material is coated on both the first interconnect terminal and the second interconnect terminal. Wherein, n1 is the preset first height difference threshold, n2 is the second height difference threshold, and n1 < n2.

17. The welding method as described in claim 12, characterized in that, When the conductive connection material is conductive adhesive, the conductive adhesive is coated on the first interconnect terminal and / or the second interconnect terminal, and the amount of conductive adhesive coated is sufficient to fill the gap between the first interconnect terminal and the second interconnect terminal.

18. A visual inspection method for a photosensitive component, used to detect the connection between the first circuit board and the second circuit board of the photosensitive component as described in any one of claims 1-4, characterized in that, include: S21. After the electrical connection is completed, the first circuit board and the second circuit board are image acquired to obtain a connection area image. The connection area image includes at least a frontal image acquired along the height direction of the photosensitive component and a side image acquired along the direction perpendicular to the height. S22. Based on the frontal image and the side image, obtain feature information, the feature information being used to provide feedback on the electrical connection between the first circuit board and the second circuit board; wherein, the feature information includes at least one of the following: the position of the first interconnect terminal, the outline shape of the first interconnect terminal, the position of the second interconnect terminal, the outline shape of the second interconnect terminal, the position of the conductive connecting material, and the outline shape of the conductive connecting material; S23. Determine the connection status of the first circuit board and the second circuit board based on the feature information.

19. The visual inspection method as described in claim 18, characterized in that, Step S23 includes: The coverage between the conductive connection material, the first interconnect terminal, and the second interconnect terminal is determined based on the feature information; If the coverage meets the preset conditions, the connection status is determined to be qualified.

20. The visual inspection method according to claim 19, characterized in that, The preset conditions include: a) In the positive image, the conductive connection material transitions uniformly between the first interconnect terminal and the second interconnect terminal, and the conductive connection material covers at least half of the first interconnect terminal and at least one-third of the second interconnect terminal; b) In the side-view image, the conductive connecting material uniformly covers the transition area and continuously covers the first interconnect terminal and the second interconnect terminal in the height direction without any breaks in between.

Images