A substrate OIS magnetic dynamic mechanism and a camera module using the same

Abstract

The present invention belongs to the technical field of imaging equipment, and discloses a substrate OIS magnetic dynamic mechanism and a camera module using the structure, which is arranged in the camera module to provide motion compensation for the sensor, including an OIS base, the OIS base is movably connected to the camera module, and the sensor is arranged on the OIS base; a plurality of coils are arranged on the OIS base, and an OIS magnet corresponding to the coil is fixed in the camera. In order to solve the problem of the existing high height of the motor, the present invention adopts the method of installing the OIS magnet on the bottom bottom cover, so that the magnet and the coil can present an ideal shape in the plane direction, and at the same time achieve the effect of reducing the overall height. The height of the magnet can be greatly reduced, thereby reducing the height of the motor.

Description

Technical Field

[0001] The present invention belongs to the technical field of imaging equipment, and in particular relates to a substrate OIS magnetic dynamic mechanism and a camera module using the structure. Background Art

[0002] The VCM motor is a device that converts electrical energy into mechanical energy and achieves linear and limited swing angle motion. It is a device that uses the interaction between the magnetic field from the permanent magnet and the magnetic poles in the magnetic field generated by the energized coil conductor to produce regular motion. Because the voice coil motor is a non-commutated power device, its positioning accuracy depends entirely on the feedback and control system and has nothing to do with the voice coil motor itself. The emergence of the VCM motor has transformed the smartphone camera from fixed focus to autofocus, while giving small or micro cameras an anti-shake function. Its biggest function is that the camera can automatically focus and provide motion compensation.

[0003] The VCM of the mobile phone camera needs the cooperation of DriverIC to complete the focus and anti-shake. The existing VCM controls the size of the VCM power supply current through DriverIC to determine the distance the lens carried by the VCM moves, so as to adjust it to the appropriate position to capture a clear image. The VCM motor actually moves based on the principle that the energized coil is subjected to force in the magnetic field. Precise control requires the help of some external components, among which the DriveIC is used to control and output the size and time of the current, thereby controlling the position that the voice coil driver needs to reach. In the mobile phone, all the control information of the DriveIC is given by the SoC, and the control logic and specific parameters are obtained by engineers through repeated adjustments during the design and manufacturing process.

[0004] At present, in the VCM motor market, ordinary VCM motors (open-loop motors) occupy the vast majority of the market share, up to 80%, and closed-loop motors account for 6%. Although both closed-loop motors and OIS motors have received great attention and are sought after, OIS motors have problems in terms of mass production and sales, such as tight resources, lack of technology, complex production process, high production difficulty, low yield, high cost, slow focusing speed, and high power consumption. Among them, the main factor causing this problem is that most of the existing OIS motors use lens anti-shake design, and this structure is bound to cause the separate electromagnetic anti-shake component to occupy a large amount of internal space, and the complex structural design and motion control are bound to bring greater obstacles to the assembly and manufacturing process, resulting in a low yield and high manufacturing cost. Summary of the invention

[0005] In order to solve the problems existing in the prior art, the present invention provides a substrate OIS magnetic driving mechanism and a camera module using the same, which can effectively reduce the size of the entire camera module.

[0006] The technical solution adopted by the present invention is:

[0007] In a first aspect, the present invention discloses a substrate OIS magnetic dynamic mechanism, which is arranged in a camera module to provide motion compensation for a sensor, and comprises an OIS base, the OIS base is movably connected to the camera module, and the sensor is arranged on the OIS base;

[0008] A plurality of coils are arranged on the OIS base, and OIS magnets corresponding to the coils are fixed in the camera.

[0009] The present invention is a fixing mechanism used in a camera (especially a micro camera module), which together with other magnetic components constitutes an anti-shake module. Anti-shake means that by adopting a special connection setting for the lens or sensor, it can maintain a certain degree of freedom in the camera, and can move in a certain range under the push of other moving bodies, so as to compensate for the shaking of the external fixing device of the camera, so that the sensor can receive external light in a relatively static state.

[0010] To realize the active optical image stabilization function, it is necessary to set an action component (generally an electromagnetic actuation combination of a magnet and an energized coil) in the camera to push the lens and / or sensor to perform active actions, and at the same time, it is necessary to maintain a certain range of freedom of movement of the lens and / or sensor in the camera module. The OIS optical image stabilization technology in the prior art is mainly aimed at lens image stabilization. Since it has the same actuation principle as the existing AF autofocus technology, it has a relatively mature technical application for lens image stabilization (especially for micro camera modules) and is relatively low in cost.

[0011] However, in order to reduce the size of many electronic devices (especially handheld terminal devices such as mobile phones), it is necessary to control the volume of other internal components while ensuring that the volume of important components such as batteries does not change. Among them, the volume control of the camera becomes the key. The imaging quality of the optical camera module is related to many factors such as sensor size, lens module, anti-shake technology and integrated algorithm. Once the volume of the entire camera module is reduced, it is bound to affect the imaging quality. In order to further reduce the impact on the imaging quality, it is necessary to adjust the structure of the optical anti-shake component that originally occupies a large space, so the sensor anti-shake technology is proposed.

[0012] The principle of sensor anti-shake is similar to that of lens anti-shake. Since the incoming light passes through the lens module before entering the sensor, motion compensation can be achieved by adjusting the movement direction of the lens or the sensor. However, since the sensor has a smaller volume, the sensor anti-shake mechanism is easier to optimize in size than the lens anti-shake mechanism, and since its weight is significantly smaller than the lens module, its motion control is also relatively simple.

[0013] The OIS base in the present invention is a component for supporting the sensor, and the OIS base and the camera are in an active connection relationship, which means that the OIS base can have a certain degree of freedom in the camera module and can be spatially displaced. Since the sensor needs to be compensated for motion, motion control is achieved by cooperating with multiple coils on the OIS base and external OIS magnets.

[0014] Among them, the coil is connected to the external circuit, and a stable magnetic field can be generated by power-on control. OIS magnets are mostly permanent magnets, which can generate an effective magnetic field environment near the coil. When the current passes through the coil and a magnetic field is generated due to the electromagnetic effect, a force can be generated for directional movement, thereby moving the OIS base carrying the sensor. The specific control signal is the corresponding control command generated by the external processor based on the motion data transmitted by the gyroscope in the same terminal device as the camera, and after assembly, the anti-shake component of each camera will be debugged to achieve a better anti-shake effect.

[0015] Unlike the prior art, due to the structural design characteristics of the camera, the OIS base carrying the sensor is often set at the bottom of the entire camera, and because of its thin thickness and large end surface, the original lateral setting of the magnet on the lens module is not suitable for this solution. In order to achieve better displacement control and volume control, integrating the coil on the OIS base can provide a more direct force. At the same time, setting the magnet at the bottom of the camera module shell and close to the corresponding coil can have better space utilization and will not interfere with the sensor or AF module. Therefore, the magnet and coil can present an ideal shape in the plane direction to achieve the effect of reducing the overall height. It is worth noting that the so-called height refers to the dimension in the axial direction of the camera.

[0016] It is also worth noting that the motion control of magnets and coils is a commonly used electromagnetic control method in the prior art, but due to different camera structures, it is necessary to adjust their positions so as to achieve the corresponding technical effects. Since the entire OIS base is a flat structure formed by injection molding of resin materials, its mass is lighter than that of the lens module. Although the OIS magnet can be set on the OIS base and the coil can be set at the bottom of the camera module, the OIS magnet will bring a significant weight-increasing effect to the OIS base, and its motion control will inevitably increase the design cost and material cost. Therefore, it is generally the best solution to set the coil on the OIS base.

[0017] In combination with the first aspect, the present invention provides a first implementation manner of the first aspect, wherein the OIS base includes a body formed by injection molding and a metal conductor arranged in the body, and the external circuit and the sensor are connected through the metal conductor; an annular groove arranged around the outer edge of the sensor is provided on the other side of the body, and a plurality of coils are arranged at equal central angles in the annular groove.

[0018] The entire OIS base is a resin cast part with a physical circuit structure inside, which can be connected to an external line to transmit data and supply power to the sensor (the data transmission function is included in this embodiment, but due to the large size of the physical circuit, it is generally only used as a power supply line, and the control line is implemented with an external FPC soft board). At the same time, in order to reduce the thickness of the entire OIS base, an annular groove is provided on the end face of the other side where the sensor is provided. The inner edge of the annular groove is larger than or exactly equal to the outer edge size of the required installation position of the sensor, so that the multiple coils arranged on the back can be arranged circumferentially around the sensor.

[0019] In combination with the first embodiment of the first aspect, the present invention provides a second embodiment of the first aspect, wherein a bottom plate is provided in the annular groove, and the coil is arranged on the bottom plate and connected to the circuit in the bottom plate.

[0020] The so-called base plate is a ring-shaped PCB printed circuit board structure, which is used to connect an external control circuit, input control current to the coil, and perform motion detection through multiple sensor pairs on the base plate.

[0021] In combination with the second implementation of the first aspect, the present invention provides a third implementation of the first aspect, further comprising a bottom cover, wherein the OIS magnet is arranged on the bottom cover.

[0022] The bottom cover is the bottom structure of the entire camera module, which is buckled with the upper shell to form a complete camera module main frame structure. Unlike the prior art, since the anti-shake component in the VCM motor is set at the lens, the sensor is generally set on the bottom cover, which means that not only a PCB board needs to be set on the bottom cover, but also an external cable needs to be connected, resulting in a separate structure for loading the cable on one side of the outside. At the same time, since the sensor, coil, and magnet are all set on the bottom cover, in order to facilitate installation, a double-layer or multi-layer structure will be used, which will not only increase the height of the entire camera module, but also increase the process difficulty and manufacturing cost during assembly. With the sensor anti-shake structure, only an OIS magnet is required on the bottom cover, and the same or better motion compensation control can be achieved by controlling the coil current on the OIS base. At the same time, it avoids the use of a multi-layer bottom cover or bottom plate structure design, simplifies the manufacturing process, thereby reducing manufacturing costs and improving product yield.

[0023] In combination with the third implementation of the first aspect, the present invention provides a fourth implementation of the first aspect, wherein the OIS base is further provided with an internal soft board which is on the same plane as the sensor, and the external control circuit, the sensor and the base plate are connected through the internal soft board.

[0024] In combination with the first aspect and first to fourth embodiments thereof, the present invention provides a fifth embodiment of the first aspect, wherein a Hall sensor is provided in the middle of the inner coil of the single or multiple coils.

[0025] It is worth mentioning that the Hall sensor is connected to the external control circuit to send the movement information of the OIS base to the outside, thereby forming a closed-loop control.

[0026] In a second aspect, the present invention further provides a camera module, which adopts the substrate OIS magnetic dynamic mechanism in the claims, and further comprises a housing and a bottom plate that are interlocked, an AF module is arranged in the housing, the OIS base is movably connected to the housing, and light incident from the AF module enters the sensor;

[0027] An FPC soft board connected to an external control circuit is arranged inside the shell, and the FPC soft board is arranged in the shell around the incident light direction as an axis.

[0028] The existing camera module also sets the power supply circuit and the control circuit independently, and the control circuit is connected by an FPC soft board. However, due to the limitation of the lens OIS mechanism, the FPC soft board in the prior art is relatively limited in its setting position, and is divided into multiple lines for independent transmission, which will inevitably increase the difficulty of the assembly process. Since the OIS anti-shake magnet assembly of the present invention is set at the bottom and occupies less space, the complex wiring can be set as an integrated structure and can be set in the housing without changing the volume of the original camera module, and there is no need to set a special fixing and bonding process, thereby reducing the process difficulty and steps, saving manufacturing costs, and improving the yield.

[0029] The beneficial effects of the present invention are:

[0030] The present invention installs the OIS magnet on the bottom cover plate, which will not interfere with the image sensor or the AF drive unit. Therefore, the magnet and the coil can present an ideal shape in the plane direction to achieve the effect of reducing the overall height. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 This is an axial schematic diagram of the assembly state of the entire camera module in Embodiment 2 of the present invention;

[0032] Figure 2 is a side schematic diagram of the assembly state of the entire camera module in Embodiment 2 of the present invention;

[0033] Figure 3is a side schematic diagram of the entire camera module in a disassembled state in Embodiment 2 of the present invention;

[0034] Figure 4 This is an axial schematic diagram of the entire camera module in a disassembled state in Embodiment 2 of the present invention;

[0035] Figure 5 This is a schematic diagram of the bottom viewing angle of the entire camera module in a disassembled state in Example 2 of the present invention;

[0036] Figure 6 It is a schematic axial side view of the assembly of some parts of the entire substrate OIS magnetic dynamic mechanism in Example 1 of the present invention;

[0037] Figure 7 It is a schematic axial side view of the partial components of the entire substrate OIS magnetic dynamic mechanism in Example 1 of the present invention;

[0038] Figure 8 It is an axial schematic diagram of a circuit board and a bottom cover where a separate coil is located in Embodiment 1 of the present invention;

[0039] Fig. 9 It is a schematic axial view of the circuit board where the individual coil is located and the bottom cover at another angle in Embodiment 1 of the present invention;

[0040] Fig.10 is a front view of the assembly state after the AF module is removed in Embodiment 2 of the present invention;

[0041] Fig.11 The present invention Fig.10 Schematic diagram of the cross section after cutting along the AA cutting line.

[0042] In the figure: 1-housing, 2-AF module, 3-FPC soft board, 3.1-inner soft board, 4-OIS base, 5-protective cover, 6-bottom cover, 7-elastic body, 8-sensor, 9-OIS magnet, 10-bottom plate, 11-coil, 12-Hall sensor. DETAILED DESCRIPTION

[0043] The present invention will be further explained below in conjunction with the accompanying drawings and specific embodiments.

[0044] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations.

[0045] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application for which protection is sought, but merely represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.

[0046] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0047] In the description of this application, it should be noted that if the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc. appear, the orientation or position relationship indicated is based on the orientation or position relationship shown in the drawings, or the orientation or position relationship in which the product of the application is usually placed when in use. It is only for the convenience of describing this application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as a limitation on this application. In addition, if the terms "first", "second", etc. appear in the description of this application, they are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0048] In addition, if the terms "horizontal" or "vertical" appear in the description of this application, it does not mean that the components are required to be absolutely horizontal or suspended, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0049] In the description of this application, it should also be noted that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal connection of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0050] Embodiment 1:

[0051] This embodiment discloses a substrate OIS magnetic driving mechanism, which is arranged in a camera module with sensor 8 anti-shake to adjust the assembly order of the internal mechanism, thereby reducing the thickness of the entire camera module.

[0052] Specifically, if Figure 6-9As shown, two main components are shown, namely the OIS base 4 and the bottom cover 6. The bottom cover 6 is the bottom baffle of the entire camera module. The circuit and sensor 8 in the prior art are all arranged at this position. Due to the large number of wirings, the prior art mostly adopts a multi-layer structure design, which is bound to lead to greater difficulty in assembly.

[0053] The OIS base 4 is movably connected to the camera module, and the sensor 8 is arranged on the OIS base 4; a plurality of coils 11 are arranged on the OIS base 4, and an OIS magnet 9 corresponding to the coil 11 is fixed in the camera. The OIS base 4 is used to support the components of the sensor 8, and the OIS base 4 and the camera are movably connected, so that the OIS base 4 can have a certain degree of freedom in the camera module and can be spatially displaced. Since it is necessary to provide motion compensation for the sensor 8, motion control is achieved by cooperating with the external OIS magnet 9 provided on the OIS base 4. The coil 11 is connected to the external circuit, and a stable magnetic field can be generated by power-on control. Since the OIS magnet 9 is mostly a permanent magnet, an effective magnetic field environment can be generated near the coil 11.

[0054] When the current flows through the coil 11 and a magnetic field is generated due to the electromagnetic effect, a force can be generated to move in a directional manner, thereby moving the OIS base 4 carrying the sensor 8. The specific control signal is a corresponding control command generated by an external processor according to the motion data transmitted by a gyroscope in the same terminal device as the camera, and after assembly, the anti-shake component of each camera will be debugged to achieve a better anti-shake effect.

[0055] In order to achieve better displacement control and volume control, integrating the coil 11 on the OIS base 4 can provide a more direct force. At the same time, setting the magnet at the bottom of the camera module housing and close to the corresponding coil 11 can have better space utilization and will not interfere with the sensor 8 or AF module 2. Therefore, the magnet and coil 11 can present an ideal shape in the plane direction to achieve the effect of reducing the overall height. It is worth noting that the so-called height refers to the dimension in the axial direction of the camera.

[0056] The entire OIS base 4 is a resin casting, with a solid circuit structure inside, which can be connected to the external circuit to transmit data and supply power to the sensor 8, and at the same time, in order to reduce the thickness of the entire OIS base 4. Specifically, the OIS base 4 includes a body formed by injection molding and a metal conductor arranged in the body, and the external circuit is connected to the sensor 8 through the metal conductor; an annular groove arranged around the outer edge of the sensor 8 is provided on the other side of the body, and multiple coils 11 are arranged at equal central angles in the annular groove. The inner edge of the annular groove is greater than or exactly equal to the outer edge size of the required installation position of the sensor 8, so that the multiple coils 11 arranged on the back can be arranged circumferentially around the sensor 8. A bottom plate 10 is provided in the annular groove, and the coil 11 is arranged on the bottom plate 10 and connected to the circuit in the bottom plate 10. The so-called bottom plate 10 is a ring-shaped PCB printed circuit board structure, which is used to connect an external control circuit, input a control current to the coil 11, and perform motion detection through multiple sensors 8 on the bottom plate 10.

[0057] The OIS base 4 is also provided with an inner soft board 3.1 on the same plane as the sensor 8, through which the external control circuit, the sensor 8 and the bottom plate 10 are connected, and a Hall sensor 128 is provided in the middle of the inner circle of the partial coil 11. The Hall sensor 128 is connected to the external control circuit to send the movement information of the OIS base 4 to the outside, thereby forming a closed-loop control.

[0058] Embodiment 2:

[0059] This embodiment discloses a camera module structure, which has the suspended image sensor 8 fixing structure in Embodiment 1.

[0060] Specifically, the camera module is designed with an 8-sensor anti-shake structure. Figure 1-4 As shown, Figure 4 The disassembled structure diagram does not show the structure being disassembled in the order of structure coverage, so it should be noted that the exterior of the entire camera module is composed of an outer shell 1 and a bottom cover 6 , and the bottom cover 6 is a single plate structure that is snapped onto the bottom opening of the outer shell 1 .

[0061] The main functional components in the housing 1 include the AF module 2, the sensor 8 and the above-mentioned suspended fixing structure. The sensor 8 is arranged on the OIS base 4, and a protective cover 5 is arranged on the sensor 8. The AF module 2 is placed on the housing 1, and a separate FPC cable is provided to connect with the external control circuit and the power supply circuit. The AF module 2 has an automatic zoom mechanism inside, which can independently complete the reciprocating motion of the lens axis in the housing 1. The OIS body 7 is arranged on the upper part of the housing 1, and a gasket connected to the housing 1 is also provided at the lower part of the body 7 for support and fixation.

[0062] In this embodiment, the suspension mechanism includes an OIS base 4 connected to the elastic body 7. The base is the same as the above-mentioned embodiment 1, and a metal plate, a metal inner body, a sensor 8 and a PCB with a coil 11 at the bottom are connected to form an integrated structure by a resin injection molding process. An FPC soft board 3 structure is also arranged around the OIS base 4. The FPC soft board 3 is connected to one end surface of the OIS base 4 provided with the sensor 8 for power supply and control signal input.

[0063] A plurality of OIS magnets 9 are also provided on the bottom cover 6, which correspond to the coils 11 provided on the OIS base 4. A specific current is input into the coils 11 through an external control circuit, thereby generating a specific magnetic field to cause the OIS base 4 to move in a directional manner on the magnets, thereby forming motion compensation.

[0064] The present invention is not limited to the above optional implementations, and anyone can derive other various forms of products under the enlightenment of the present invention. The above specific implementations should not be understood as limiting the scope of protection of the present invention. The scope of protection of the present invention should be based on the definition in the claims, and the description can be used to interpret the claims.

Claims

1. A substrate OIS magnetic motion mechanism, arranged in a camera module to provide motion compensation for a sensor (8), Features: It comprises an OIS base (4), the OIS base (4) being movably connected to the camera module, and the sensor (8) being arranged on the OIS base (4); A plurality of coils (11) are provided on the OIS base (4), and an OIS magnet (9) corresponding to the coils (11) is fixed in the camera. The OIS base (4) comprises a body formed by injection molding and a metal conductor arranged in the body, and the external circuit is connected to the sensor (8) via the metal conductor; an annular groove arranged around the outer edge of the sensor (8) is provided on the other side of the body, and a plurality of coils (11) are arranged at equal central angles in the annular groove; A bottom plate (10) is provided in the annular groove, and the coil (11) is arranged on the bottom plate (10) and connected to a circuit in the bottom plate (10); The OIS base (4) is also provided with an FPC soft board (3) structure, the FPC soft board (3) is connected to an end surface of one side of the OIS base (4) provided with a sensor (8), and is used for power supply and control signal input, the FPC soft board (3) being arranged around the sensor (8) with the direction of incident light as an axis; the OIS base (4) is also provided with an inner soft board (3.1) located on the same plane as the sensor (8), and an external control circuit, the sensor (8) and the base plate (10) are connected via the inner soft board (3.1); The base plate (10) is a ring-shaped PCB printed circuit board structure, and the base plate (10) is used to connect an external control circuit, input a control current to the coil (11), and perform motion detection through a plurality of sensor pairs on the base plate (10).

2. The substrate OIS magnetic drive mechanism according to claim 1, Features: It also includes a bottom cover (6), and the OIS magnet (9) is arranged on the bottom cover (6).

3. The substrate OIS magnetic drive mechanism according to claim 1, Features: A Hall sensor (12) is provided in the middle of the inner coil of one or more of the coils (11).

4. A camera module, Features: The substrate OIS magnetomotive mechanism of claim 3 is adopted.

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