WO2024040692A1

WO2024040692A1 - Core-driven-type autofocus camera module

Info

Publication number: WO2024040692A1
Application number: PCT/CN2022/123736
Authority: WO
Inventors: 麦练智
Original assignee: 高瞻创新科技有限公司
Priority date: 2022-08-20
Filing date: 2022-10-08
Publication date: 2024-02-29
Also published as: CN115242955A

Abstract

The present disclosure relates to a core-driven-type autofocus camera module, which resolves problems such as soft circuit boards of existing core-driven-type autofocus cameras shifting easily when moving, occupying a large space and having poor heat dissipation. The module comprises a housing, a lens arranged on the housing, a circuit board arranged in the housing, an image sensor, a position sensor, and a driving mechanism. When in use, the position sensor is used for detecting displacement of the image sensor so as to implement autofocusing. When a circuit board body moves upwards, a deformation supporting part is restored to provide a downward restoring force for a supporting connecting part. When the circuit board body moves downwards, the deformation supporting part is restored to provide an upward restoring force for the supporting connecting part. When the camera module is not working, the restoring force resets a movable seat to reduce the impact of the movable seat on other components and abnormal sound caused by external vibrations. In addition, when the circuit board body moves up and down, same is not prone to tilting, the positioning is accurate, and the occupied space is small. Furthermore, heat dissipation efficiency of the image sensor is increased.

Description

A core-driven autofocus camera module

Technical field

The invention relates to a core-driven autofocus camera module.

Background technique

Theoretically, core-type actuators have more advantages in power consumption and size. However, the actuator technology has many shortcomings, which prevents this type of technology from becoming mainstream. The actuator (reference patents: CN113325543A, CN214959775U and CN 112684565A) and its application camera module require a flexible circuit board to connect the image sensor in the movable structure and the electronic parts outside the fixed structure to provide power to the The image sensor sends the image signal to the electronic component. The flexible circuit board can adopt a planar deformation design (reference patents: CN113325543A and CN214959775U) or a multiple folding deformation design (reference patent: CN112684565A). Regardless of whether it is a flat or multiple folding deformation design, the deformation part of the flexible circuit board also needs to occupy more space, occupying space outside the camera module, under or next to the image sensor. In addition, the multiple folding deformation design and production process are complicated, which is not conducive to production cost and yield rate.

In addition, some core-action actuators adopt a shrapnel-type design (refer to patents: CN113325543A and CN214959775U). When the lens is stationary, a large current and electromagnetic force are still required to resist the force caused by the deformation of the shrapnel, resulting in greater power consumption. On the other hand, the spring-type design is more sensitive to the size and assembly errors of the flexible circuit board, and is prone to unnecessary tilting of the image sensor during the automatic process, affecting the resolution of the image edges. In addition, the magnets in some core-operated actuators (reference patent: CN112684565A) are movable. When other magnets are near the actuator, they can easily interfere with the magnets, which may cause serious magnetic interference. affect the normal operation of the actuator.

Finally, since the image sensor in the actuator needs to move during the autofocus process, the circuit board under the image sensor cannot be close to the housing, affecting the heat dissipation effect. The design of the actuator or camera module fails to provide an effective heat dissipation path in a limited space. Poor heat dissipation can lead to a higher temperature of the image sensor, which may cause more image noise or even fail to work properly.

technical problem

The purpose of the present invention is to solve the problems that the flexible circuit board of the existing core-action autofocus camera is prone to deflection when moving, takes up a large space, and has poor heat dissipation.

Technical solutions

The technical solution adopted to solve the technical problems raised by the present invention is: the core-driven autofocus camera module of the present invention includes a housing, a lens provided on the housing, a circuit board provided in the housing, and a circuit board provided in the housing. An image sensor is provided on the circuit board corresponding to the lens. The circuit board includes a circuit board main body. The image sensor is located on the circuit board main body. The housing includes a shell and a movable seat. The movable seat The base slides along the axial direction of the lens and is installed in the housing. The circuit board main body is installed on the movable base. The camera module also includes a driving mechanism that drives the movable base to move relative to the lens. The movable base is also provided with There is a position sensor for detecting the displacement of the image sensor. The circuit board also includes a support connection part connected to the circuit board main body that moves up and down along with the circuit board main body, a flexible deformation support part connected to the support connection part, and A mounting base connected to the deformation support part. The middle part of the deformation support part is provided with a through hole corresponding to the image sensor. The minimum distance from the plane where the deformation support part is located to the image sensor is greater than one-tenth of the corresponding lens height; The mounting base is electrically connected to the main body of the circuit board, and the mounting base is installed in the housing.

Technical solutions that further limit the present invention include:

The housing is provided with more than two lenses, and each lens is provided with a movable seat, a circuit board, an image sensor, a driving mechanism and a position sensor.

The driving mechanism is a voice coil motor driving mechanism, the first coil of the voice coil motor driving mechanism is installed on the movable seat, and the first magnet of the voice coil motor is installed on the casing.

One side of the movable seat is connected to the shell through rolling balls. The side of the movable seat corresponding to the ball is provided with a magnetic conductive seat. The side of the shell corresponding to the ball is provided with a magnetic conductive seat opposite to the magnetic conductive seat. Adsorbed by the second magnet.

The first coil is located on the other side of the movable seat adjacent to the magnetic conductive seat. The first magnet is arranged corresponding to the first coil. The first magnet adopts single-sided bipolar magnetization. The upper side of the magnet facing the coil is the north pole, and the lower side of the first magnet facing the coil is the south pole.

The first coil is located on the other side of the movable seat adjacent to the magnetic conductive seat. The first magnet is arranged corresponding to the first coil. The first magnet includes a third magnet arranged oppositely up and down. The fourth magnet, the third magnet and the fourth magnet face opposite magnetic poles of the first coil; the movable seat is provided with a second coil on the other side opposite to the first coil, and the shell corresponding to the second coil is provided with an upper and lower opposite The fifth magnet and the sixth magnet are arranged so that the fifth magnet and the sixth magnet face opposite magnetic poles of the second coil.

The angle between the plane where the deformation support part is located and the image sensor is less than 20 degrees.

The deformation support part is composed of two or more layers of deformation support part units, and a gap is provided between adjacent deformation support part units.

The support connection part includes at least one connection surface with a vertical angle of less than 30 degrees to the lens axis.

The supporting connection part includes at least one connection surface with a total area larger than half of the image sensor.

beneficial effects

Through the above technical solutions, the beneficial effects of the present invention are: the core-moving autofocus camera module of the present invention electrically connects the circuit board through the mounting base. When in use, the driving mechanism drives the movable base to drive the image sensor to move relative to the lens, and the position sensor It is used to detect the displacement of the image sensor to achieve automatic focusing. The image sensor corresponds to the through hole in the middle of the deformation support part. The support connection part of the circuit board is located in the space around the image sensor, so the overall structure is compact and takes up little space. When the main body of the circuit board moves up, the support connection part moves up with the main body of the circuit board, and the deformation support part deforms upward. At the same time, the deformation support part recovers to provide a downward restoring force for the support connection part; when the main body of the circuit board moves down, The support connection part moves downward with the main body of the circuit board, and at the same time, the deformed support part recovers to provide an upward restoring force for the support connection part; when the camera module is not working, the restoring force will reset the movable seat to reduce external vibration. Cause the movable seat to hit other parts and make abnormal noise. In addition, when the circuit board main body moves up and down, because the deformation support portion exerts a small moment on the center of the circuit board main body, the circuit board main body is less likely to tilt and the positioning is accurate. Furthermore, the support connection part and the deformation support part in the circuit board effectively increase the effective heat dissipation area of the image sensor, improve the heat dissipation efficiency, and reduce the temperature and noise of the image sensor.

Description of drawings

Figure 1 is a schematic three-dimensional structural diagram of a core-driven autofocus camera module of the present invention.

FIG. 2 is a schematic three-dimensional structural diagram of a core-driven autofocus camera module according to Embodiment 1 of the present invention.

FIG. 3 is a schematic structural diagram of the driving mechanism of a core-driven autofocus camera module according to Embodiment 1 of the present invention.

FIG. 4 is a schematic cross-sectional structural diagram of a core-driven autofocus camera module according to Embodiment 1 of the present invention.

FIG. 5 is a schematic cross-sectional structural diagram of a core-driven autofocus camera module according to Embodiment 1 of the present invention.

FIG. 6 is a schematic structural diagram of the driving mechanism of a core-driven autofocus camera module according to the second embodiment of the present invention.

FIG. 7 is a schematic structural diagram of a circuit board of a core-driven autofocus camera module according to the present invention.

8 is a schematic structural diagram of a circuit board of a core-type autofocus camera module according to the present invention when the deformation support portion is composed of two layers.

FIG. 9 is an enlarged structure of position A in FIG. 8 .

Best Mode of Carrying Out the Invention

The structure of the present invention will be further described below with reference to the accompanying drawings.

In the description of this application, it should be understood that the terms "center", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", The orientations or positional relationships indicated by "top", "bottom", "inner", "outside", etc. are based on the orientations or positional relationships shown in the drawings. They are only for the convenience of describing the present application and simplifying the description, and are not indicated or implied. The devices or components referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore are not to be construed as limitations on the application.

Referring to Figures 1 to 9, a core-driven autofocus camera module includes a housing 10, a lens 11 located on the housing, a circuit board 20 located in the housing, and a corresponding lens located on the circuit board. The image sensor 30 is provided. The circuit board 20 includes a circuit board main body 21. The image sensor is located on the circuit board main body. The housing 10 includes a housing 101 and a movable seat 102. The movable seat slides along the axial direction of the lens and is provided in the housing. The circuit The main body of the board is installed on the movable seat. The camera module also includes a driving mechanism 40 that drives the movable seat to move relative to the lens. The movable seat is also provided with a position sensor 50 for detecting the displacement of the image sensor. The circuit board 20 also includes a circuit The support connection part 22 connected to the circuit board body moves up and down along with the circuit board body, the flexible deformation support part 23 connected to the support connection part, and the mounting base 24 connected to the deformation support part. The middle part of the deformation support part 23 corresponds to the image sensor device. There is a through hole 231, and the minimum distance from the plane where the deformation support part is located to the image sensor is greater than one-tenth of the corresponding lens height. If the distance is too small, the deformed part will have to avoid the image sensor and surrounding electronic components, which cannot save space. The mounting base is electrically connected to the main body of the circuit board, and the mounting base is installed in the housing. The circuit board is electrically connected through the mounting base. When in use, the driving mechanism drives the movable base to drive the image sensor to move relative to the lens. The position sensor is used to detect the displacement of the image sensor to achieve automatic focusing. The image sensor corresponds to the through hole in the middle of the deformation support part. The supporting connection part of the circuit board is located in the space around the image sensor, so that the overall structure is compact and takes up little space. When the main body of the circuit board moves up, the support connection part moves up with the main body of the circuit board, and the deformation support part deforms upward. At the same time, the deformation support part recovers to provide a downward restoring force for the support connection part; when the main body of the circuit board moves down, The support connection part moves downward with the main body of the circuit board, and at the same time, the deformed support part recovers to provide an upward restoring force for the support connection part; when the camera module is not working, the restoring force will reset the movable seat to reduce external vibration. Cause the movable seat to hit other parts and make abnormal noise. In addition, when the circuit board main body moves up and down, because the deformation support portion exerts a small moment on the center of the circuit board main body, the circuit board main body is less likely to tilt and the positioning is accurate. Furthermore, the support connection part and the deformation support part in the circuit board effectively increase the effective heat dissipation area of the image sensor, improve the heat dissipation efficiency, and reduce the temperature and noise of the image sensor.

In this embodiment, the outer shell adopts a dark coating to improve the efficiency of absorbing thermal radiation and further reduce the temperature and noise of the image sensor.

In this embodiment, the housing is provided with a lens, a circuit board, an image sensor, a driving mechanism and a position sensor. During specific implementation, more than two lenses can be provided on the housing, and each lens is provided with a movable seat, a circuit board, an image sensor, a driving mechanism and a position sensor. This enables multi-lens autofocus.

In this embodiment, the driving mechanism 40 is a voice coil motor driving mechanism. The first coil 41 of the voice coil motor driving mechanism is installed on the movable seat, and the first magnet 42 of the voice coil motor is installed on the housing. Changing the current of the first coil can change the electromagnetic force and direction of the first coil, driving the movable seat to drive the image sensor to move relative to the lens to achieve an automatic focusing effect. During specific implementation, other types of driving mechanisms can be used, such as spring-type voice coil motors, memory metal motors and piezoelectric motors, instead of ball-type voice coil motors; other numbers of magnets, coils and shell designs are also used in the present invention. within the scope of protection.

In this embodiment, one side of the movable seat is rollingly connected to the shell through balls 60. The side of the movable seat corresponding to the balls is provided with a magnetic seat 70, and the side of the shell corresponding to the balls is provided with a magnetic seat that is attracted to the magnetic seat. Second magnet 80. The second magnet and the magnetic base are attracted to each other, which can press the movable base and the housing on the balls, restricting the movable base from moving along the lens axis, and making it less likely to shift. The magnetic seat is made of magnetic material and can be attracted by magnets.

In the first embodiment, the first coil is disposed on the other side of the movable seat adjacent to the magnetic conductive seat, and the first magnet is disposed corresponding to the first coil. The first magnet 42 adopts single-sided bipolar magnetization. The upper side of the first magnet facing the coil is the north pole, and the lower side of the first magnet facing the coil is the south pole. When the first wire is powered on, it can generate an electromagnetic force roughly parallel to the optical axis, pushing the movable seat to drive the image sensor to move relative to the lens, achieving an automatic focusing effect.

In the second embodiment, the first coil is disposed on the other side of the movable seat adjacent to the magnetic conductive seat, and the first magnet is disposed corresponding to the first coil. The first magnet 42 includes a third magnet 421 and a third magnet 421 arranged oppositely up and down. Four magnets 422, the third magnet and the fourth magnet face opposite magnetic poles of the first coil; the movable seat is provided with a second coil 43 on the other side opposite to the first coil, and the shell corresponding to the second coil is provided with oppositely arranged up and down The fifth magnet 44 and the sixth magnet 45 face opposite magnetic poles of the second coil. When the first coil and the second coil are energized, an electromagnetic force roughly parallel to the optical axis can be generated to push the movable seat to drive the image sensor to move relative to the lens to achieve an automatic focusing effect. The position sensor 50 can measure the position of the first coil relative to the third magnet and the fourth magnet, and adjust the current of the first coil and the second coil to achieve a closed-loop control effect. The position sensor integrated in the driver chip and the driver chip integrated in the position sensor are both within the scope of protection.

In this embodiment, the angle between the plane where the deformation support part is located and the image sensor is 0 degrees. At this time, the upper and lower spring constants are the smallest and the power consumption is the smallest. Specifically, the angle between the plane where the deformation support part is located and the image sensor is less than 20 degrees. If the angle is too large, the upper and lower spring constants will be too large and the power consumption will be too high.

In this embodiment, the support connection part 22 includes at least one connection surface parallel to the lens axis. During specific implementation, the deformation support part may include at least one connecting surface with a vertical angle of less than 30 degrees to the lens axis. This allows the image sensor to move along the axis of the lens without tilting and positioning accurately without affecting camera imaging.

In this embodiment, the support connection part includes at least one connection surface with a total area larger than half of the image sensor. The metal part in the support connection part is connected to the image sensor, which can effectively conduct heat from the image sensor to the support connection. part, and then transferred to the outer casing through thermal radiation and thermal convection, effectively reducing the temperature and noise of the image sensor. In this embodiment, the deformation support part 23 is composed of two or more layers of deformation support part units 232, and a gap 233 is provided between adjacent deformation support part units. This layered design can reduce the thickness of the deformation support part alone, effectively reduce the spring constant in the optical axis displacement direction of the deformation support part, and reduce the power consumption required for autofocus.

In this embodiment, the deformation support part is electrically connected to the main body of the circuit board. The deformation support part 23 includes an annular frame with a notch 234, and the image sensor is arranged corresponding to the middle part of the annular frame; both ends of the notch of the annular frame are respectively bent. The flexible connecting portion 25 is electrically connected to the mounting base. The flexible connection part causes the deformation support part to deform evenly, making the deformation support part deform more stably. When the main body of the circuit board moves up and down, it drives the image sensor to move up and down. The image sensor is set corresponding to the middle of the annular frame. The annular frame is set around the image sensor. The annular frame has a certain degree of elasticity. While satisfying elastic deformation, it has a compact structure and takes up less space. Small. The deformation support part can be a Flexible Printed Circuit (FPC) flexible circuit board. Easy to manufacture and low cost.

In this embodiment, the connection between the annular frame and the supporting connection part is a straight edge, and the notched annular frame is a notched rectangular annular frame, which facilitates manufacturing and reduces the cost. In the third specific implementation, the notched annular frame may also be a notched elliptical annular frame, a notched polygonal annular frame, or a notched special-shaped annular frame.

Although the specific embodiments of the present invention have been described in detail with reference to the accompanying drawings, this should not be understood as limiting the scope of the present invention. Within the scope described in the claims, various modifications and transformations that can be made by those skilled in the art without creative efforts still belong to the protection scope of the present invention.

Claims

A core-driven autofocus camera module. The camera module includes a housing, a lens provided on the housing, a circuit board provided in the housing, and an image set by the corresponding lens provided on the circuit board. The sensor is characterized in that: the circuit board includes a circuit board main body, the image sensor is located on the circuit board main body, the housing includes a shell, and a movable seat, and the movable seat is along the lens axis. The circuit board is slidably installed in the casing, and the circuit board main body is installed on the movable seat. The camera module also includes a driving mechanism that drives the movable seat to move relative to the lens. The movable seat is also provided with an image sensor for detecting the image. The position sensor of the displacement, the circuit board also includes a support connection part connected with the circuit board main body that moves up and down along with the circuit board main body, a flexible deformation support part connected with the support connection part, and a flexible deformation support part connected with the deformation support part The mounting base has a through hole corresponding to the image sensor in the middle of the deformation support part, and the minimum distance from the plane of the deformation support part to the image sensor is greater than one-tenth of the corresponding lens height; the mounting base It is electrically connected to the main body of the circuit board, and the mounting base is installed in the casing.
A circuit board for core-driven autofocus according to claim 1, characterized in that: the housing is provided with more than two lenses, and each lens is provided with a movable seat and a circuit. board, an image sensor, a drive mechanism and a position sensor.
A circuit board used in core-driven autofocus according to claim 1, characterized in that: the driving mechanism is a voice coil motor driving mechanism, and the first coil of the voice coil motor driving mechanism is installed on the movable seat , the first magnet of the voice coil motor is installed on the housing.
A circuit board used in core-driven autofocus according to claim 3, characterized in that: one side of the movable seat is rollingly connected to the housing through a ball, and the movable seat corresponds to one side of the ball. A magnetic conductive seat is provided on one side, and a second magnet adsorbed on the magnetic conductive seat is provided on the side of the housing corresponding to the ball.
A circuit board used in core-driven autofocus according to claim 4, characterized in that: the first coil is located on the other side of the movable seat adjacent to the magnetic permeable seat, and the third coil A magnet is provided corresponding to the first coil. The first magnet adopts single-sided bipolar magnetization. The upper surface of the first magnet facing the coil is the north pole, and the lower surface of the first magnet facing the coil is the south pole.
A circuit board used in core-driven autofocus according to claim 4, characterized in that: the first coil is located on the other side of the movable seat adjacent to the magnetic permeable seat, and the third coil A magnet is arranged corresponding to the first coil. The first magnet includes a third magnet and a fourth magnet arranged oppositely up and down. The third magnet and the fourth magnet face opposite magnetic poles of the first coil; the movable seat is opposite to each other. A second coil is provided on the other side of the first coil, and a fifth magnet and a sixth magnet arranged vertically and oppositely are provided on the housing corresponding to the second coil. The fifth magnet and the sixth magnet face opposite magnetic poles of the second coil.
The circuit board used in core motion autofocus according to any one of claims 1 to 6, characterized in that: the angle between the plane where the deformation support part is located and the image sensor is less than 20 degrees.
A circuit board used in core-motion autofocus according to any one of claims 1 to 6, characterized in that: the deformation support part is composed of more than two layers of deformation support parts, and the adjacent deformation support parts are There is a gap between the supporting parts.
A core-action autofocus camera module according to any one of claims 1 to 6, characterized in that: the support connection part includes a vertical angle between at least one connection surface and the lens axis. less than 30 degrees.
A core-driven autofocus camera module according to any one of claims 1 to 6, characterized in that the support connection part includes at least one connection surface with a total area larger than half of the image sensor.