Auto-focus camera module and auto-focus camera module assembly method

Abstract

The present invention relates to the field of camera technology, and specifically discloses an autofocus camera module, including an upper lens group, a T-lens, a lower lens group, a base and a circuit board; the T-lens is arranged between the upper lens group and the lower lens group; the top and side walls of the lower lens group are provided with conductive circuits; the side walls corresponding to the base and the lower lens group are also provided with conductive circuits; the conductive circuits of the lower lens group are electrically connected to the guide circuits of the base, and the conductive circuits of the base are electrically connected to the circuit board. The technical solution of the present invention can realize autofocus in a smaller structural size.

Description

Technical Field

[0001] The present invention relates to the technical field of cameras, and in particular to an auto-focus camera module and an auto-focus camera module assembly method. Background Art

[0002] At present, cameras have been widely used in mobile phones, tablets, notebooks, security, automotive, medical, monitoring and other fields. In the application process of cameras in different fields, different requirements are put forward for various parameters of cameras. For example, mobile phone cameras used in the consumer field are required to have a smaller structure size, and while the structure size of the camera becomes smaller, the quality requirements of the photos taken by the camera are constantly improving; the front camera of the mobile phone must have a small head and a small size while also realizing the focus function.

[0003] Therefore, an auto-focus camera module with a smaller structural size and an auto-focus camera module assembly method are needed. Summary of the invention

[0004] The present invention provides an automatic focusing camera module, which can realize automatic focusing in a relatively small structure size.

[0005] In order to solve the above technical problems, this application provides the following technical solutions:

[0006] An autofocus camera module, including an upper lens group, a T-lens, a lower lens group, a base and a circuit board;

[0007] The T-lens is set between the upper lens group and the lower lens group;

[0008] Conductive circuits are arranged on the top and side walls of the lower lens group; conductive circuits are also arranged on the side walls corresponding to the base and the lower lens group;

[0009] The conductive circuit of the lower lens group is electrically connected to the guide circuit of the base, and the conductive circuit of the base is electrically connected to the circuit board.

[0010] The basic scheme principles and beneficial effects are as follows:

[0011] In the prior art, the T-lens is usually placed directly on the top of the camera module, but this increases the height of the camera, and because the T-lens needs to be powered on, placing the wiring on the top will also increase the size of the camera in the X / Y direction, affecting the camera's appearance, and it is impossible to make a small head camera. This solution places the T-lens between the upper lens group and the lower lens group, and completes the optical path design together with the entire lens. The conductive circuit is directly set on the lower lens group and the outer wall of the base, which reduces the volume occupied by the wiring layout, while meeting the power supply requirements of the T-lens and reducing the size of the camera. When the T-lens is powered on, the surface curvature will change, allowing the lens to achieve zoom. It can replace the AF motor function. The T-lens also has the advantages of fast focus and low power consumption, which improves the performance of the camera module.

[0012] In summary, this solution can achieve autofocus in a smaller structural size.

[0013] Furthermore, the upper lens group includes an upper lens barrel, a first lens, and a second lens; the first lens and the second lens are sequentially arranged in the upper lens barrel;

[0014] The lower lens group includes a lower lens barrel, a third lens, a fourth lens, and a fifth lens; the third lens, the fourth lens, and the fifth lens are sequentially arranged in the lower lens barrel;

[0015] Conductive circuits are arranged on the top and side walls of the lower lens barrel.

[0016] Furthermore, the lower lens barrel and the base are molded from LDS material, and the conductive circuit is obtained by laser engraving and then copper plating.

[0017] The LDS copper plating process uses a CNC laser to directly transfer the circuit pattern to the surface of the molded plastic original, and uses the three-dimensional surface of the three-dimensional workpiece to form a circuit interconnection structure. This technology can achieve T-lens conductivity without increasing the size of the module.

[0018] The auto-focus camera module assembly method comprises the following steps:

[0019] S1, the top and side walls of the lower lens barrel, the base and the side walls corresponding to the lower lens barrel are copper plated by LDS process to form a conductive circuit;

[0020] S2, attaching the photosensitive chip to the circuit board;

[0021] S4. Fit the base to the circuit board, and fit the T-lens to the lower lens barrel;

[0022] S5, connect the positive and negative electrodes of the T-lens to the conductive circuits of the lower lens barrel respectively;

[0023] S6, fit the upper lens barrel to the lower lens barrel, and the lower lens barrel to the base;

[0024] S7, electrically connecting the conductive circuit of the lower lens barrel and the conductive circuit of the base, and the conductive circuit of the base and the circuit board.

[0025] This solution places the T-lens between the upper lens group and the lower lens group, and completes the optical path design together with the entire lens. The conductive circuit is directly set on the lower lens group and the outer wall of the base, reducing the volume occupied by the circuit layout, while meeting the power supply requirements of the T-lens and reducing the size of the camera.

[0026] Further, in S6, the upper lens barrel and the lower lens barrel, and the lower lens barrel and the base are bonded together by an AOA process; the AOA process specifically includes:

[0027] S601, light up the photosensitive chip;

[0028] S602, placing the upper lens barrel and the lower lens barrel simultaneously above the photosensitive chip for imaging;

[0029] S603, confirming the clarity of the test image through the photosensitive chip, and determining the relative positions of the upper lens barrel and the lower lens barrel based on the clarity;

[0030] S604, fix the upper lens barrel, the lower lens barrel and the base.

[0031] The lens is divided into two groups, upper and lower, and cannot be completed using conventional AA technology. It requires that after the photosensitive chip is lit, the upper and lower groups are placed on top of the photosensitive chip at the same time to form an image. The clarity of the test image is confirmed by the photosensitive chip to determine the required reduction and position of the upper and lower groups, which are fixed by painting glue to meet the camera performance requirements.

[0032] Furthermore, in step S5, the positive electrode and the negative electrode of the T-lens are respectively connected to the conductive circuit of the lower lens barrel by a gold wire punching process.

[0033] Furthermore, in step S603, it is determined whether the offset between the upper lens barrel and the lower lens barrel exceeds a preset offset range based on the relative positions of the upper lens barrel and the lower lens barrel. If so, an alarm is issued.

[0034] It is possible to avoid assembling the upper lens barrel and the lower lens barrel with excessive offset. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 An exploded view of the auto-focus camera module of Example 1;

[0036] Figure 2 for Figure 1 A partial enlarged view of part A in the middle. DETAILED DESCRIPTION

[0037] The following is further described in detail through specific implementation methods:

[0038] The symbols in the drawings of the specification include: upper lens group 1, T-lens 2, lower lens group 3, base 4, filter 5, photosensitive chip 6, circuit board 7, conductive line 8, gold wire 9.

[0039] Embodiment 1

[0040] like Figure 1 As shown, the auto-focus camera module of this embodiment includes: an upper lens group 1, a T-lens 2, a lower lens group 3, a base 4, a filter 5, a photosensitive chip 6 and a circuit board 7.

[0041] The upper lens group 1 includes an upper lens barrel, a first lens, a second lens, and a plurality of first spacers; in this embodiment, the number of the first spacers is 1; the first lens, the second lens, and the first spacer are arranged in the upper lens barrel, and the first spacer is located between the first lens and the second lens, and is used to separate the first lens and the second lens, control the distance between the first lens and the second lens, and prevent the first lens and the second lens from rubbing against each other. In this embodiment, the edge thickness of the first lens is 0.2mm, and the edge thickness of the second lens is 0.1mm.

[0042] The lower lens group 3 includes a lower lens barrel, a third lens, a fourth lens, a fifth lens, and a plurality of second spacers. In this embodiment, the number of the second spacers is 3. The third lens, the fourth lens, the fifth lens, and the second spacer are arranged in the lower lens barrel. The three second spacers are respectively located between the lower lens barrel and the third lens, between the third lens and the fourth lens, and between the fourth lens and the fifth lens. In this embodiment, the edge thickness of the third lens is 0.18 mm.

[0043] The T-lens 2 is disposed between the upper lens group 1 and the lower lens group 3. The T-lens 2 includes a piezoelectric film, a glass film, a high molecular polymer and a glass support.

[0044] The filter 5 is fixed in the base 4, and the photosensitive chip 6 is installed on the circuit board 7; the upper lens group 1, T-lens 2, the lower lens group 3, the base 4, the photosensitive chip 6 and the circuit board 7 are combined in sequence from top to bottom to form a camera module.

[0045] The top and side walls of the lower lens barrel are provided with a conductive circuit 8; the side walls of the base 4 corresponding to the lower lens barrel are also provided with a conductive circuit 8. In this embodiment, the lower lens barrel and the base 4 are molded from LDS material, and the conductive circuit 8 is obtained by laser engraving and copper plating. LDS material is a modified plastic containing an organic metal complex, which releases particles after laser irradiation.

[0046] The conductive circuit 8 of the lower lens barrel is electrically connected to the guide circuit of the base 4 , and the conductive circuit 8 of the base 4 is electrically connected to the circuit board 7 .

[0047] like Figure 2 As shown, the positive and negative electrodes of T-lens 2 are connected to the conductive circuit 8 of the lower lens barrel by gold wires 9. When the circuit board 7 is powered on, the photosensitive chip 6 is lit and the T-lens 2 is powered on at the same time.

[0048] When in use, the piezoelectric film forms an extrusion force after the positive and negative electrodes of T-lens2 are voltaged. The polymer is deformed by the extrusion, and the glass film bulges, thereby changing the focal length of T-lens2. The focal length change of T-lens2 is combined with the upper lens group 1 and the lower lens group 3 to achieve the change of the focal length of the entire lens.

[0049] When the camera module shoots scenes at different distances, T-lens2 will quickly focus in a cycle. When the sightseeing chip is most sensitive to light, T-lens2 will be fixed to achieve fast focus and obtain the clearest picture.

[0050] Based on the auto-focus camera module, this embodiment also provides an auto-focus camera module assembly method, comprising the following steps:

[0051] S1. The top and side walls of the lower lens barrel, the base 4 and the side walls corresponding to the lower lens barrel are copper-plated by the LDS process to form a conductive circuit 8; the LDS process copper plating refers to the technology of using a CNC laser to directly transfer the circuit pattern to the surface of the molded plastic original part, and using the three-dimensional surface of the three-dimensional workpiece to form a circuit interconnection structure.

[0052] S2, attaching the photosensitive chip 6 to the circuit board 7 through the COB packaging process;

[0053] S4, using the LHA device to bond the base 4 to the circuit board 7, and to bond the T-lens 2 to the lower lens barrel; specifically, the LHA device is provided with upper and lower adsorption fixtures and upper and lower two CCDs. Taking bonding the base 4 to the circuit board 7 as an example, the upper adsorption fixture adsorbs the base 4, and identifies the edge contour of the base 4 through the lower CCD, the lower adsorption fixture adsorbs the circuit board 7, and identifies the chip contour through the upper CCD, and then glue is drawn on the circuit board 7. According to the edge contour of the base 4 and the chip contour identified by the upper and lower CCDs, the center of the base 4 and the circuit board 7 is calculated, and the base 4 and the circuit board are assembled and bonded together. The bonding of the T-lens 2 to the lower lens barrel is also performed by calculating the center of the T-lens 2 and the lower lens barrel according to the edge contour of the T-lens 2 and the edge contour of the lower lens barrel, and then bonding.

[0054] S5, connecting the positive electrode and the negative electrode of T-lens 2 to the conductive line 8 of the lower lens barrel respectively through the gold wire punching process;

[0055] S6. The upper lens barrel, the lower lens barrel, and the base 4 are bonded together by the AOA process. Compared with the existing lens, in this embodiment, the camera module is divided into an upper lens group 1 and a lower lens group 3, and the conventional AA process cannot be used to complete the bonding. The AOA process specifically includes:

[0056] S601, lighting up the photosensitive chip 6;

[0057] S602, placing the upper lens barrel and the lower lens barrel simultaneously above the photosensitive chip 6 for imaging;

[0058] S603, confirming the clarity of the test image through the photosensitive chip 6, and determining the relative positions of the upper lens barrel and the lower lens barrel based on the clarity; in this embodiment, the side view is a Chart.

[0059] S604, fixing the upper lens barrel, the lower lens barrel and the base 4 by applying glue;

[0060] S7, connect the T-lens 2 to the circuit board 7 through the silver glue filling process; specifically, fill the silver glue between the conductive circuit 8 of the lower lens barrel and the conductive circuit 8 of the base 4, and between the conductive circuit 8 of the base 4 and the circuit board 7.

[0061] The conventional application is to place the T-lens2 directly on the top of the camera module, which increases the height of the camera module. Since the T-lens2 needs to be powered, placing the wiring on the top will also increase the size of the camera module in the X / Y direction, affecting the appearance of the camera module and making it impossible to reduce the size of the camera module. The solution places the T-lens2 between the second lens and the third lens, and completes the optical path design together with the entire lens, which beautifies the appearance of the camera module and reduces the size of the camera module. In this solution, by setting the T-lens2 between the upper lens group 1 and the lower lens group 3, the surface curvature of the T-lens2 will change under the action of the power voltage, allowing the lens to achieve zoom. It can replace the AF motor function. The T-lens2 also has the advantages of fast focus and low power consumption, which improves the performance of the camera module.

[0062] Since the thickness of the T-lens2 body is 0.4mm, the positive and negative electrodes also need to have a gold wire arc height of 0.08mm and an AA process glue thickness of 0.12mm (including the gold wire arc height), that is, a distance of 0.42mm needs to be reserved between the second lens and the third lens, while the design distance of conventional lenses is 0.06mm, which greatly increases the difficulty of light design. In this solution, the required distance is reserved by reducing the edge thickness of the first lens from 0.3mm to 0.2mm, the edge thickness of the second lens from 0.3mm to 0.1mm, and the edge thickness of the third lens from 0.3mm to 0.18mm.

[0063] Embodiment 2

[0064] The difference between this embodiment and the first embodiment is that in step S603 of this embodiment, it is also determined whether the offset between the upper lens barrel and the lower lens barrel exceeds the preset offset range. If so, an alarm is issued, and the T-lens is powered by an external power supply to adjust the surface curvature of the T-lens. The clarity of the test image is confirmed again by the photosensitive chip, and the relative positions of the upper lens barrel and the lower lens barrel are determined based on the clarity. It is further determined whether the offset between the upper lens barrel and the lower lens barrel exceeds the preset offset range. If not, it is determined to be a T-lens problem. If so, the edge contour of the T-lens of the present camera module and the edge contour of the lower lens barrel, as well as the edge contour of the T-lens of the previous camera module and the edge contour of the lower lens barrel, are obtained in step S4. The edge contours of the two T-lens and the edge contours of the two lower lens barrels are compared to determine whether there are differences. If there are differences, it is determined to be a T-lens problem. If there are no differences, it is determined to be a lens problem.

[0065] In this embodiment, when the upper lens barrel, the lower lens barrel, and the base are fitted together, the offset between the upper lens barrel and the lower lens barrel may exceed the preset offset range. At this time, there may be a problem with the optical path of the lens or T-lens, resulting in excessive offset, and a preliminary judgment of the cause is required. By using an external power supply, the T-lens can be powered on in advance, and the surface curvature of the T-lens can be adjusted before imaging, and the relative positions of the upper lens barrel and the lower lens barrel can be adjusted. If the relative positions of the upper lens barrel and the lower lens barrel do not exceed the preset offset range, it is proved that the optical path problem has been solved. It is likely that there is a problem with the initial surface curvature of the T-lens, so it is judged to be a T-lens problem. If the offset still exceeds the preset range, it proves that the optical path problem cannot be solved by adjusting the curvature of the T-lens surface; by comparing the edge contour of the T-lens of this camera module with the edge contour of the lower lens barrel, and the edge contour of the T-lens of the previous camera module with the edge contour of the lower lens barrel, if there is a difference, it may be that the difference in the edge contour causes a difference in the calculated center of the T-lens and the lower lens barrel, which in turn causes a problem in the fit of the T-lens and the lower lens barrel. If there is no difference, the center of the T-lens of this camera module and the lower lens barrel is consistent with the center of the previous camera module, and the problem of the fit of the T-lens and the lower lens barrel is ruled out, so it is judged that there is a problem when installing the lens.

[0066] The above are only embodiments of the present invention. The invention is not limited to the fields involved in this implementation case. The common sense such as the known specific structures and characteristics in the scheme is not described in detail here. The ordinary technicians in the relevant field know all the common technical knowledge in the technical field to which the invention belongs before the application date or the priority date, can obtain all the existing technologies in the field, and have the ability to apply the conventional experimental means before that date. The ordinary technicians in the relevant field can improve and implement this scheme in combination with their own abilities under the enlightenment given by this application. Some typical known structures or known methods should not become obstacles for ordinary technicians in the relevant field to implement this application. It should be pointed out that for those skilled in the art, without departing from the structure of the present invention, several deformations and improvements can be made, which should also be regarded as the protection scope of the present invention, which will not affect the effect of the implementation of the present invention and the practicality of the patent. The protection scope required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to explain the content of the claims.

Claims

1. An auto-focus camera module assembly method, characterized in that: The steps include: S1, the top and side walls of the lower lens barrel, the base and the side walls corresponding to the lower lens barrel are copper plated by LDS process to form a conductive circuit; S2, attaching the photosensitive chip to the circuit board; S4. Fit the base to the circuit board, and fit the T-lens to the lower lens barrel; S5, connect the positive and negative electrodes of the T-lens to the conductive circuits of the lower lens barrel respectively; S6, fit the upper lens barrel to the lower lens barrel, and the lower lens barrel to the base; S7, electrically connecting the conductive circuit of the lower lens barrel and the conductive circuit of the base, and the conductive circuit of the base and the circuit board; In S6, the upper lens barrel and the lower lens barrel, and the lower lens barrel and the base are bonded together by the AOA process; The AOA process specifically includes: S601, light up the photosensitive chip; S602, placing the upper lens barrel and the lower lens barrel simultaneously above the photosensitive chip for imaging; S603, confirming the clarity of the test image through the photosensitive chip, and determining the relative positions of the upper lens barrel and the lower lens barrel based on the clarity; S604, fixing the upper lens barrel, the lower lens barrel and the base; In step S603, it is also determined whether the offset between the upper lens barrel and the lower lens barrel exceeds the preset offset range. If so, an alarm is issued, and the T-lens is powered by an external power supply to adjust the surface curvature of the T-lens. The clarity of the test image is confirmed again by the photosensitive chip, and the relative positions of the upper lens barrel and the lower lens barrel are determined based on the clarity. It is further determined whether the offset between the upper lens barrel and the lower lens barrel exceeds the preset offset range. If not, it is determined to be a T-lens problem. If so, the edge contour of the T-lens of the present camera module and the edge contour of the lower lens barrel, as well as the edge contour of the T-lens of the previous camera module and the edge contour of the lower lens barrel, are obtained in step S4. The edge contours of the two T-lens and the edge contours of the two lower lens barrels are compared to determine whether there are any differences. If there are differences, it is determined to be a T-lens problem. If there are no differences, it is determined to be a lens problem.

2. The method for assembling an auto-focus camera module according to claim 1, wherein: In the step S5, the positive electrode and the negative electrode of the T-lens are respectively connected to the conductive circuit of the lower lens barrel by a gold wire punching process.

3. An auto-focus camera module, using the auto-focus camera module assembly method according to any one of claims 1 to 2, characterized in that: Including upper lens group, T-lens, lower lens group, base and circuit board; The T-lens is set between the upper lens group and the lower lens group; Conductive circuits are arranged on the top and side walls of the lower lens group; The side walls of the base corresponding to the lower lens group are also provided with conductive circuits; The conductive circuit of the lower lens group is electrically connected to the guide circuit of the base, and the conductive circuit of the base is electrically connected to the circuit board.

4. The auto-focus camera module according to claim 3, characterized in that: The upper lens group includes an upper lens barrel, a first lens, and a second lens; the first lens and the second lens are sequentially arranged in the upper lens barrel; The lower lens group includes a lower lens barrel, a third lens, a fourth lens, and a fifth lens; the third lens, the fourth lens, and the fifth lens are sequentially arranged in the lower lens barrel; Conductive circuits are arranged on the top and side walls of the lower lens barrel.

5. The auto-focus camera module according to claim 3, characterized in that: The lower lens barrel and the base are molded from LDS material, and the conductive circuit is obtained by laser engraving and then copper plating.

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