Optical image stabilization module lens connector and camera module

Abstract

The present invention discloses a lens connector and a camera module of an optical image stabilization module, and belongs to the field of optical image stabilization technology. In the present invention, a circular hole is provided in the center of a supporting plate; a rotating base includes a rotating member and a support plate with a rotating platform in the center, the support plate is in contact with the upper surface of the supporting plate and the rotating platform is arranged in the circular hole, the rotating member is fixedly connected to the outer bottom surface of the rotating platform and is in contact with the lower surface of the supporting plate; an actuator assembly connects the rotating member and the connecting plate, and is used to drive the rotating base to rotate relative to the circular hole. In the lens connector of the optical image stabilization module of the present invention, the actuator assembly drives the rotating base to rotate around the optical axis, the rotating base will not be displaced parallel to the optical axis, the rotating base has good motion stability, the actuator assembly has a large driving force and high efficiency, and can achieve a high-precision image stabilization effect.

Description

Technical Field

[0001] The present invention relates to the technical field of optical image stabilization, and in particular to a lens connector and a camera module of an optical image stabilization module. Background Art

[0002] In recent years, the use of miniature camera modules has become increasingly popular, with their application scope continuously expanding to include various handheld mobile devices such as smartphones and tablets. When shooting with handheld mobile devices, the inevitable human factor of motion often results in blurry photos or videos, especially in low-light conditions.

[0003] In order to solve the above technical problems, there are various micro anti-shake pan-tilt heads that use voice coil motors as driving devices in the relevant technologies, and there are also anti-shake modules that use SMA wire drives. Most of these micro anti-shake pan-tilt heads do not directly drive the lens module to rotate around the optical axis. When the lens module rotates around the optical axis, the moment of inertia is large, which causes a large burden on the driving device and affects the anti-shake effect. In addition, in the relevant technologies, the upper limit of the lens module anti-shake process in the direction parallel to the optical axis is slightly lacking, which causes the micro camera module to move unstably during the optical anti-shake process, affecting the anti-shake accuracy. Summary of the Invention

[0004] The present invention aims to solve one of the technical problems existing in the prior art. To this end, the present invention provides a lens connector for an optical image stabilization module, which can reduce the moment of inertia of the lens module rotating about the optical axis in the camera and enhance the position limitation of the lens module in a direction parallel to the optical axis during the image stabilization process, thereby improving the image stabilization effect.

[0005] The lens connector of the optical image stabilization module according to the first embodiment of the present invention includes:

[0006] A supporting plate, wherein a circular hole is formed in the center of the supporting plate;

[0007] A rotating base, comprising a rotating member and a support plate with a rotating platform at the center, wherein the support plate contacts the upper surface of the supporting plate and the rotating platform is sleeved in the circular hole, and the rotating member is fixedly connected to the outer bottom surface of the rotating platform and contacts the lower surface of the supporting plate;

[0008] The actuator assembly includes a connecting plate and an SMA wire. The connecting plate is fixedly arranged on the lower surface of the supporting plate. The SMA wire connects the rotating member and the connecting plate. When the SMA wire is energized, it can contract to generate a torque to pull the rotating base to rotate relative to the circular hole.

[0009] The lens connector for an optical image stabilization module according to an embodiment of the present invention has at least the following beneficial effects: the rotating base of the rotating platform is mounted within a circular hole; a rotating member is disposed on the outer bottom surface of the rotating base; a support plate contacts the upper surface of the carrier plate; and the rotating member contacts the lower surface of the base plate. These members can jointly constrain the vertical position of the rotating base, allowing the rotating base to move only about the optical axis without moving parallel to the optical axis, thereby ensuring stability during rotation and improving optical image stabilization accuracy. A connecting plate is disposed on the lower surface of the carrier plate, and SMA wires connect the ends of the rotating arms to the connecting plate. During use, power can be applied to one of the SMA wires to contract, generating a torque that pulls the rotating arm to rotate. The rotating arm then drives the rotating base to rotate about the circular hole, thereby rotating the rotating base about the optical axis, achieving adjustment. Selecting an SMA wire instead of a voice coil motor as the drive device avoids the generation of magnetic fields, preventing any impact on electronic components mounted on the rotating base, and preventing electronic component failure and other operational issues.

[0010] According to some embodiments of the present invention, protrusions are provided on both the upper and lower surfaces of the carrier plate, and the protrusions are arranged along the circumference of the circular hole. The bottom surface of the support plate abuts against the protrusions on the upper surface of the carrier plate, and the rotating part abuts against the protrusions on the lower surface of the carrier plate.

[0011] According to some embodiments of the present invention, two "V"-shaped connecting pieces are provided in the middle of the bottom surface of the rotating part, the two ends of the "V"-shaped connecting piece constitute two connecting ears, and the openings of the two "V"-shaped connecting pieces are arranged back to back; the number of the connecting plates is consistent with the number of the connecting ears; the SMA wires are respectively connected to the connecting ears and the connecting plates.

[0012] According to some embodiments of the present invention, an elastic arm is further included, wherein the elastic arm connects the supporting plate and the rotating platform and is used to drive the rotating base to reset.

[0013] According to some embodiments of the present invention, the rotating member includes a rotating arm and a rotating frame, the rotating frame is fixedly arranged on the outer bottom surface of the rotating table, the elastic arm and the rotating frame are integrally formed, the rotating arm is fixedly arranged on the bottom surface of the rotating frame, and the "V"-shaped connecting piece is arranged in the middle of the bottom surface of the rotating arm.

[0014] According to some embodiments of the present invention, the rotating frame is provided with a plurality of supporting legs, and the supporting legs abut against the protrusions.

[0015] According to some embodiments of the present invention, a limiting groove is opened on the hole wall of the circular hole, and a limiting block is provided on the rotating frame. The limiting block is arranged along the circumference of the circular hole and cooperates with the limiting groove to limit the rotation of the rotating base.

[0016] According to some embodiments of the present invention, the supporting plate is a composite plate, comprising an upper plate, a middle plate and a lower plate; the protrusions are respectively provided on the upper plate and the lower plate.

[0017] According to some embodiments of the present invention, the upper plate and the lower plate are metal plates, and an insulating layer is coated on the surfaces of the upper plate and the lower plate.

[0018] According to another embodiment of the present invention, a camera module includes the lens connector of the above-mentioned optical image stabilization module.

[0019] Additional aspects and advantages of the present invention will be set forth in part in the description which follows and, in part, will be obvious from the description which follows, or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the following description of the embodiments with reference to the accompanying drawings, in which:

[0021] Figure 1 This is a three-dimensional diagram of a lens connector of an optical image stabilization module in an embodiment of the present invention.

[0022] Figure 2 for Figure 1 A stereoscopic view of the lens adapter from another perspective is shown.

[0023] Figure 3 This is an exploded view of an embodiment of the present invention when the rotating member is a rotating arm.

[0024] Figure 4 This is an exploded view of a lens connector according to an embodiment of the present invention including an elastic arm.

[0025] Figure 5 This is an exploded view of a lens connector according to an embodiment of the present invention when the rotating member is a rotating arm and a rotating frame.

[0026] Figure 6 This is a three-dimensional diagram of a rotating frame in one embodiment of the present invention.

[0027] Figure 7 FIG. 1 is a bottom view of an actuator assembly according to an embodiment of the present invention.

[0028] Figure 8 This is an exploded view of a load-bearing plate in one embodiment of the present invention.

[0029] Figure 9 It is a stereoscopic diagram of a camera module in another embodiment of the present invention.

[0030] Figure Number:

[0031] Carrying plate 1; circular hole 11; protrusion 12; upper plate 1a; middle plate 1b; lower plate 1c;

[0032] Rotating base 2; rotating platform 22; supporting plate 21; rotating arm 23;

[0033] "V" shaped connecting piece 231; connecting ear 2311; limiting groove 24;

[0034] Limit block 25;

[0035] Actuator assembly 3;

[0036] Connecting plate 31; SMA wire 32;

[0037] First connecting plate 31a; second connecting plate 31b; third connecting plate 31c; fourth connecting plate 31d;

[0038] A first SMA wire 32a; a second SMA wire 32b; a third SMA wire 32c; and a fourth SMA wire 32d;

[0039] Elastic arm 4; fixing plate 41;

[0040] Rotating frame 5; Support legs 51;

[0041] Lens module 6. DETAILED DESCRIPTION

[0042] The following describes embodiments of the present invention in detail. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended only to explain the present invention and are not to be construed as limiting the present invention.

[0043] In the description of the present invention, it should be understood that descriptions involving orientations, such as up, down, left, right, front, and back, etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they cannot be understood as limitations on the present invention.

[0044] In the description of the present invention, unless otherwise clearly defined, terms such as setting, installing, and connecting should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in the present invention based on the specific content of the technical solution.

[0045] Reference below Figures 1 to 9 The lens connector of the optical image stabilization module according to the first embodiment of the present invention will be described.

[0046] The lens connector of the optical image stabilization module according to an embodiment of the present invention includes:

[0047] The carrier plate 1 has a circular hole 11 in the center;

[0048] The rotating base 2 includes a rotating member and a support plate 21 with a rotating platform 22 at the center. The support plate 21 contacts the upper surface of the carrier plate 1 and the rotating platform 22 is sleeved in the circular hole 11. The rotating member is fixedly connected to the outer bottom surface of the rotating platform 22 and contacts the lower surface of the carrier plate 1.

[0049] The actuator assembly includes a connecting plate and an SMA wire. The connecting plate is fixedly arranged on the lower surface of the supporting plate 1. The SMA wire connects the rotating part and the connecting plate. When the SMA wire is energized, it can contract and generate a torque to pull the rotating base 2 to rotate relative to the circular hole 11.

[0050] refer to Figure 1 and Figure 2 , a circular hole 11 is opened in the center of the supporting plate 1. The supporting plate 1 can be of any shape and can be movably set on other adjustment modules. The rotating base 2 includes a support plate 21 with a rotating table 22 in the center and a rotating member. The rotating table 22 is sleeved in the circular hole 11. The diameter of the rotating table 22 is slightly smaller than the circular hole 11, so that the rotating table 22 can move slightly in the radial direction in the circular hole 11, thereby increasing the adjustment range. The rotating member is fixedly arranged on the outer bottom surface of the rotating table 22. The support plate 21 contacts the upper surface of the supporting plate 1, and the rotating member contacts the lower surface of the supporting plate 1. It can ensure that the rotating table 22 will not be displaced along the optical axis direction, and further improve the stability of the movement.

[0051] The actuator assembly includes a connecting plate 31 and an SMA wire 32. The SMA wire 32 connects the rotating part and the connecting plate 31. Since the SMA wire 32 has the characteristic of contracting when energized, when in use, energizing a certain SMA wire 32 can cause it to contract and generate a torque to pull the rotating part to rotate. The number of connecting plates 31 and SMA wires 32 is the same and multiple groups can be set. They are also arranged along the circumference of the circular hole 11, which can pull the rotating part from multiple different directions, increase the rotation accuracy of the rotating base 2, and thus improve the anti-shake effect. Since the actuator assembly only drives the rotating base 2 to rotate, the driving burden of the actuator assembly is relatively small, and the driving force can be transmitted more efficiently, thereby improving the sensitivity of the anti-shake and saving energy. Selecting the SMA wire 32 as the driving device can eliminate the influence of the magnetic field factor in the related technology and improve the working efficiency.

[0052] In some specific embodiments of the present invention, protrusions 12 are provided on the upper and lower surfaces of the supporting plate 1, and the protrusions 12 are arranged along the circumference of the circular hole 11. The bottom surface of the support plate 21 abuts against the protrusions 12 on the upper surface of the supporting plate 1, and the rotating part abuts against the protrusions 12 on the lower surface of the supporting plate 1.

[0053] The protrusion 12 can be in any shape, such as a ring, an arc or a disc arranged around the circumference of the circular hole 11. Figure 3 and Figure 4 The protrusion 12 is disc-shaped and is arranged on the upper and lower surfaces of the carrier plate 1 along the circumference of the circular hole 11. The top surface of the protrusion 12 is an arc-shaped with a small curvature. The bottom surface of the support plate 21 contacts the protrusion 12 on the upper surface of the carrier plate 1, which can reduce the contact area between the bottom surface of the support plate 21 and the carrier plate 1, which is beneficial to reduce the suction force caused by the overly close contact between the bottom surface of the support plate 21 and the upper surface of the carrier plate 1, and between the rotating part and the lower surface of the carrier plate 1, thereby reducing the friction when the rotating base 2 rotates and saving driving energy consumption. The rotating arm 23 contacts the protrusion 12 on the lower surface of the carrier plate 1, which can also reduce the friction when the rotating base 2 rotates and save driving energy consumption.

[0054] In some specific embodiments of the present invention, two "V"-shaped connecting pieces 231 are provided in the middle of the bottom surface of the rotating part, and the two ends of the "V"-shaped connecting piece 231 constitute two connecting ears 2311, and the openings of the two "V"-shaped connecting pieces 231 are arranged back to back; the number of connecting plates 31 is consistent with the number of connecting ears 2311, and they are symmetrically arranged along the circular hole 11 on the bottom surface of the supporting plate 1; the SMA wire 32 connects the connecting ears 2311 and the connecting plate 31 respectively.

[0055] refer to Figure 2 、 Figure 3 and Figure 7The SMA wires 32 are provided with four pieces, namely a first SMA wire 32a, a second SMA wire 32b, a third SMA wire 32c, and a fourth SMA wire 32d. The connecting plate 31 also has four pieces, namely a first connecting plate 31a, a second connecting plate 31b, a third connecting plate 31b, and a fourth connecting plate 31d. The first SMA wire 32a connects the first connecting plate 31a and one of the connecting ears 2311, and the second SMA wire 32b connects the second connecting plate 31b and one of the connecting ears 2311. When viewed from above, the first SMA wire 32a and the second SMA wire 32b are perpendicular to each other. The third SMA wire 32c connects the third connecting plate 31b and one of the connecting ears 2311, and the fourth SMA wire 32d connects the fourth connecting plate 31d and one of the connecting ears 2311. When viewed from above, the third Z-axis SMA wire and the fourth Z-axis SMA wire are perpendicular to each other. Among them, the two "V"-shaped connecting plates 231 are inconsistent in height, the first connecting plate 31a and the fourth connecting plate 31d are consistent in height, and are at the same height as one of the "V"-shaped connecting plates 231, the second connecting plate 31b and the third connecting plate 31c are consistent in height, and are at the same height as the other "V"-shaped connecting plate 231; the first connecting plate 31a and the second connecting plate 31b are arranged adjacent to each other, and the third connecting plate 31b and the fourth connecting plate 31d are arranged adjacent to each other; the first SMA wire 32a and the second SMA wire 32b are separated by a certain height distance, and the third SMA wire 32c and the fourth SMA wire 32d are separated by a certain height distance, which can prevent short circuits between the SMA wires, or poor heat dissipation caused by too close distances. With this arrangement, any one of the SMA wires 32 can be energized to contract, generating a torque that pulls the rotating member to rotate. Alternatively, the first and third SMA wires 32a, 32c can be energized simultaneously to contract, generating a torque that pulls the rotating base 2 counterclockwise about the optical axis. Alternatively, the second and fourth SMA wires 32b, 32d can be energized simultaneously to contract, generating a torque that pulls the rotating base 2 clockwise about the optical axis. Furthermore, two V-shaped connecting pieces 231 are positioned at the rotation center of the rotating member. The SMA wires 32 connect the connecting ears 2311 on the V-shaped connecting pieces 231 to the connecting plates, shortening the distance between each SMA wire 32 and the rotation center. When the SMA wires 32 are contracted to a certain length, the closer they are to the rotation center, the greater the rotation angle of the rotating base 2.

[0056] In some specific embodiments of the present invention, the rotating member includes a rotating arm 23. Figure 3 The rotating arm 23 is disposed on the outer bottom surface of the rotating platform 22. Specifically, the rotating arm 23 and the rotating platform 22 can be welded, bonded, or otherwise fixedly connected. Both ends of the rotating arm 23 abut against the protrusion 12. A "V"-shaped connecting piece 231 is disposed on the bottom surface of the rotating arm 23 and is integrally formed with the rotating arm 23. This arrangement helps simplify the assembly process.

[0057] In some specific embodiments of the present invention, an elastic arm 4 is further included. The elastic arm 4 connects the supporting plate 1 and the rotating platform 22 and is used to drive the rotating base 2 to reset.

[0058] refer to Figure 4 Two elastic arms 4 are provided, and the two elastic arms 4 are symmetrically arranged along the center of the circular hole 11. The two elastic arms 4 are integrally formed and fixedly connected to the outer bottom surface of the rotating table 22 via a fixing plate 41. The top surface of the rotating arm 23 is fixedly connected to the fixing plate 41. This arrangement is conducive to simplifying the processing and assembly process. When the SMA wire 32 is no longer energized, the elastic arm 4 can reset the rotating table 22 because the SMA wire 32 cannot automatically return to its original shape. The elastic arm 4 is serpentine and has multiple bends, which is conducive to improving the elasticity of the elastic arm 4. When the SMA wire 32 is energized and contracts, the better elasticity of the elastic arm 4 makes it less obstructive to the contraction process of the SMA wire 32.

[0059] In some specific embodiments of the present invention, the rotating member includes a rotating arm 23 and a rotating frame 5. The rotating frame 5 is fixedly arranged on the outer bottom surface of the rotating platform 22. The elastic arm 4 and the rotating frame 5 are integrally formed. The rotating arm 23 is fixedly arranged on the bottom surface of the rotating frame 5. The "V"-shaped connecting piece 231 is arranged in the middle of the bottom surface of the rotating arm 23.

[0060] refer to Figure 5 The elastic arm 4 and the rotating frame 5 are integrally formed, and the "V"-shaped connecting piece 231 and the rotating arm 23 are integrally formed, which can simplify the assembly process and improve assembly efficiency.

[0061] In some specific embodiments of the present invention, the rotating frame 5 is provided with a plurality of supporting legs 51 , and the supporting legs 51 abut against the protrusions 12 .

[0062] refer to Figure 5 There are four protrusions 12 on the upper surface and the lower surface of the supporting plate 1, and the rotating frame 5 is provided with four supporting feet 51, which abut against the protrusions 12. Through such an arrangement, the rotating frame 5 can make multi-point contact with the supporting plate 1, thereby increasing the stability of the rotating table 22 during rotation, which is beneficial to improving the optical image stabilization performance.

[0063] In some specific embodiments of the present invention, a limiting groove 24 is opened on the hole wall of the circular hole 11, and a limiting block 25 is provided on the rotating frame 5. The limiting block 25 is arranged along the circumference of the circular hole 11 and cooperates with the limiting groove 24 to limit the rotation of the rotating base 2.

[0064] refer to Figure 5A limit block 25 is provided on the rotating member along the circumference of the circular hole 11, and a limit slot 24 is provided on the wall of the circular hole 11. The width of the limit slot 24 is slightly larger than the width of the limit block 25. The limit block 25 extends into the limit slot 24 in the circular hole 11 and cooperates with the limit slot 24 to provide a limiting function. Specifically, when the rotating base 2 is subjected to a large external force and rotates along the optical axis, the cooperation between the limit slot 24 and the limit block 25 can limit the rotation angle to a certain range, preventing the SMA wire 32 from being torn due to excessive rotation.

[0065] In some specific embodiments of the present invention, the carrier plate 1 is a composite plate, including an upper plate 1a, a middle plate 1b and a lower plate 1c; the protrusions 12 are respectively provided on the upper plate 1a and the lower plate 1c. Figure 8 The carrier plate 1 is configured as a composite plate, and the protrusions 12 are respectively provided on the upper plate 1a and the lower plate 1c, and can be integrally formed with the upper plate 1a or the lower plate 1c, respectively, for easy processing.

[0066] In some specific embodiments of the present invention, the upper and lower plates 1a and 1c are metal plates coated with an insulating layer. Both plates 1a and 1c are stamped from metal sheets in a single operation to ensure a certain degree of deformation resistance. In practical applications, these plates will house circuits, and the insulating layer prevents short circuits between circuits that could damage component operation and ensure module safety. The middle plate 1b can be made of other non-metallic materials to reduce structural weight.

[0067] In the camera module of the second embodiment of the present invention, refer to Figure 9 , including an optical image stabilization module and a lens module 6, the optical image stabilization module including the lens connection seat in the first embodiment, wherein the lens module 6 is arranged on the rotating base 2. Through such an arrangement, the optical image stabilization performance of the camera module can be improved, thereby improving the imaging quality.

[0068] Specifically, the lens module 6 is connected to the upper surface of the support plate 21, and the optical image stabilization module is provided with two sets of driving devices (not shown in the drawings) for driving the carrier plate 1 to rotate around the X-axis and Y-axis perpendicular to the optical axis, where the X-axis and Y-axis are perpendicular to each other, so that the lens module 6 can have an anti-shake effect in three rotation directions.

[0069] The embodiments of the present invention are described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments. Various changes can be made within the scope of knowledge possessed by ordinary technicians in the technical field without departing from the spirit of the present invention.

Claims

1. The lens connector of the optical image stabilization module is characterized by: include: A supporting plate, wherein a circular hole is formed in the center of the supporting plate; A rotating base, comprising a rotating member and a support plate with a rotating platform at the center, wherein the support plate contacts the upper surface of the supporting plate, and the rotating platform is sleeved in the circular hole, and the rotating member is fixedly connected to the outer bottom surface of the rotating platform and contacts the lower surface of the supporting plate; An actuator assembly, comprising a connecting plate and an SMA wire, wherein the connecting plate is fixedly disposed on the lower surface of the bearing plate, and the SMA wire connects the rotating member and the connecting plate. When energized, the SMA wire can contract to generate a torque to pull the rotating base to rotate relative to the circular hole; An elastic arm is connected to the supporting plate and the rotating platform, and is used to drive the rotating base to reset.

2. The lens connector of the optical image stabilization module according to claim 1, characterized in that: Protrusions are provided on both the upper and lower surfaces of the carrier plate. The protrusions are arranged along the circumference of the circular hole. The bottom surface of the support plate abuts against the protrusions on the upper surface of the carrier plate, and the rotating member abuts against the protrusions on the lower surface of the carrier plate.

3. The lens connector of the optical image stabilization module according to claim 1, characterized in that: Two "V"-shaped connecting pieces are provided in the middle of the bottom surface of the rotating part, and the two ends of the "V"-shaped connecting pieces constitute two connecting ears, and the openings of the two "V"-shaped connecting pieces are arranged back to back; the number of the connecting plates is consistent with the number of the connecting ears; the two ends of the SMA wire are respectively connected to the connecting ears and the connecting plates.

4. The lens connector of the optical image stabilization module according to claim 3, characterized in that: The rotating member includes a rotating arm and a rotating frame. The rotating frame is fixedly arranged on the outer bottom surface of the rotating platform. The elastic arm and the rotating frame are integrally formed. The rotating arm is fixedly arranged on the bottom surface of the rotating frame. The "V"-shaped connecting piece is arranged in the middle of the bottom surface of the rotating arm.

5. The lens connector of the optical image stabilization module according to claim 4, characterized in that: A protrusion is provided on the lower surface of the carrying plate, and the protrusion is arranged along the circumference of the circular hole. The rotating frame is provided with a plurality of supporting legs, and the supporting legs are in contact with the protrusion.

6. The lens connector of the optical image stabilization module according to claim 4, characterized in that: A limiting groove is provided on the hole wall of the circular hole, and a limiting block is provided on the rotating frame. The limiting block is provided along the circumference of the circular hole and cooperates with the limiting groove to jointly limit the rotation of the rotating base.

7. The lens connector of the optical image stabilization module according to claim 2, characterized in that: The bearing plate is a composite plate, which includes an upper plate, a middle plate and a lower plate; the protrusions are respectively arranged on the upper plate and the lower plate.

8. The lens connector of the optical image stabilization module according to claim 7, characterized in that: The upper plate and the lower plate are metal plates, and an insulating layer is coated on the surfaces of the upper plate and the lower plate.

9. A camera module, characterized in that: A lens connector comprising the optical image stabilization module according to any one of claims 1 to 8.

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