阅读说明：本技术 摄像模组、电子设备及摄像模组的控制方法 (Camera module, electronic equipment and control method of camera module ) 是由 成东村 罗政军 于 2019-09-30 设计创作，主要内容包括：本发明公开一种摄像模组,其包括第一支架(100)、摄像头(200)、底座(300)、第一驱动模组(400)和第二驱动模组(500),其中：所述摄像头(200)与所述第一支架(100)转动相连,所述第一支架(100)与所述底座(300)转动相连；所述第一驱动模组(400)根据所述摄像模组的倾斜角度驱动所述摄像头(200)绕第一轴线转动；所述第二驱动模组(500)根据所述倾斜角度驱动所述第一支架(100)绕第二轴线转动,所述第一轴线与所述第二轴线相交或异面。上述方案能解决目前的电子设备无法有效防抖,进而存在电子设备的拍摄质量较差的问题。本发明公开一种电子设备及摄像模组的控制方法。(The invention discloses a camera module, which comprises a first bracket (100), a camera (200), a base (300), a first driving module (400) and a second driving module (500), wherein: the camera (200) is rotatably connected with the first bracket (100), and the first bracket (100) is rotatably connected with the base (300); the first driving module (400) drives the camera (200) to rotate around a first axis according to the inclination angle of the camera module; the second driving module (500) drives the first support (100) to rotate around a second axis according to the inclination angle, and the first axis is intersected with the second axis or is out of plane. Above-mentioned scheme can solve present electronic equipment can't effective anti-shake, and then has electronic equipment's the relatively poor problem of shooting quality. The invention discloses electronic equipment and a control method of a camera module.)

1. The utility model provides a camera module, its characterized in that includes first support (100), camera (200), base (300), first drive module (400) and second drive module (500), wherein:

the camera (200) is rotatably connected with the first bracket (100), and the first bracket (100) is rotatably connected with the base (300);

the first driving module (400) drives the camera (200) to rotate around a first axis according to the inclination angle of the camera module;

the second driving module (500) drives the first support (100) to rotate around a second axis according to the inclination angle, and the first axis is intersected with the second axis or is out of plane.

2. The camera module of claim 1, wherein the first drive module (400) comprises a first magnet (410) and a first drive coil (420), one of the first magnet (410) and the first drive coil (420) is coupled to the camera head (200) and the other is coupled to the first bracket (100), and the camera head (200) rotates relative to the first bracket (100) through the cooperation of the first magnet (410) and the first drive coil (420).

3. The camera module according to claim 2, wherein the first drive module (400) further comprises a first hall device (430), one of the first hall device (430) and the first magnet (410) is connected to the camera (200), the other is connected to the first bracket (100), the first hall device (430) detects a first rotation angle of the camera (200), an angular component of the inclination angle in a direction in which the camera (200) rotates about the first axis is a first angular component, and the first drive coil (420) is powered off in a case where the first rotation angle is opposite to and equal to the first angular component.

4. The camera module according to claim 3, wherein the first Hall device (430) and the first drive coil (420) are mounted on the first bracket (100) and are disposed on either side of the first axis, respectively, and the first magnet (410) is coupled to the camera head (200).

5. The camera module according to claim 2, characterized in that the first bracket (100) is provided with a first hinge hole, the first bracket (100) is provided with a first hinge shaft (110), the first hinge shaft (110) is in hinge fit with the first hinge hole, the axis of the first hinge shaft (110) is the first axis, and the first magnet (410) and the camera (200) are both connected with the first hinge shaft (110).

6. The camera module according to claim 1, wherein the second drive module (500) comprises a second magnet (510) and a second drive coil (520), one of the second magnet (510) and the second drive coil (520) being disposed on the first bracket (100) and the other being disposed on the base (300), the first bracket (100) being rotatable relative to the base (300) by engagement of the second magnet (510) with the second drive coil (520).

7. The camera module according to claim 6, wherein the second drive module (500) further includes a second hall device (530), one of the second hall device (530) and the second magnet (510) is provided on the first bracket (100) and the other is provided on the base (300), the second hall device (530) detects a second rotation angle of the first bracket (100), an angular component of the inclination angle in a direction in which the first bracket (100) rotates about the second axis is a second angular component, and the second drive coil (520) is deenergized in a case where the second rotation angle is opposite in direction and equal to the second angular component.

8. The camera module according to claim 7, wherein the second hall device (530) and the second driving coil (520) are both mounted on the first bracket (100) and are respectively disposed on both sides of the second axis, and the second magnet (510) is disposed on the base (300).

9. The camera module according to claim 8, wherein the base (300) is provided with a second hinge hole (310), the first bracket (100) is provided with a second hinge shaft (120), an axis of the second hinge shaft (120) is the second axis, and the second hinge shaft (120) is hinged to the second hinge hole (310).

10. The camera module according to claim 1, further comprising a second bracket (600), wherein the camera (200) is fixedly connected with the second bracket (600), and the second bracket (600) is rotatably connected with the first bracket (100).

11. The camera module according to claim 10, characterized in that the second bracket (600) is a hood-like structure which is housed on the camera head (200).

12. The camera module of claim 1, wherein the first frame (100) is a frame-type structure, and the camera (200) is disposed in an area enclosed by the first frame (100).

13. The camera module of claim 1, wherein the base (300) is a frame-like structure, and the first bracket (100) is disposed within an area enclosed by the base (300).

14. The camera module of claim 1, further comprising an angle detection device for detecting an angle of inclination of the camera module.

15. An electronic device comprising the camera module of any one of claims 1-14.

16. A method for controlling a camera module, applied to an electronic device, wherein the camera module is the camera module according to any one of claims 1 to 14, the method comprising:

acquiring the inclination angle of the camera module;

determining a first angular component of the tilt angle in a direction about the first axis and a second angular component in a direction about the second axis;

controlling the first driving module (400) to drive the camera (200) to rotate reversely by a first angle component;

controlling the second driving module (500) to drive the first support (100) to reverse a second angular component.

Technical Field

The invention relates to the technical field of communication equipment, in particular to a camera module, electronic equipment and a control method of the camera module.

Background

With the advancement of technology, electronic devices (e.g., mobile phones, tablet computers) have been developed. As a powerful tool, the electronic equipment brings great convenience to the life and work of users. The camera shooting function is a basic function of the electronic equipment and can meet the shooting requirements of users. The camera function is usually implemented by a camera module of the electronic device.

In a specific working process, a user usually holds the electronic device by hand to shoot an image, and the image quality shot by the camera module is poor due to shaking in the holding process.

Disclosure of Invention

The invention discloses a camera module, which aims to solve the problem that the shooting quality of electronic equipment is poor due to the fact that the conventional electronic equipment cannot effectively prevent shaking.

In order to solve the problems, the invention adopts the following technical scheme:

the utility model provides a camera module, includes first support, camera, base, first drive module and second drive module, wherein:

the camera is rotationally connected with the first support, and the first support is rotationally connected with the base;

the first driving module drives the camera to rotate around a first axis according to the inclination angle of the camera shooting module;

the second driving module drives the first support to rotate around a second axis according to the inclination angle, and the first axis is intersected with the second axis or is out of plane.

An electronic device comprises the camera module.

A control method of a camera module is provided, the camera module is the camera module described above, and the control method includes:

acquiring the inclination angle of the camera module;

determining a first angular component of the tilt angle in a direction about the first axis and a second angular component in a direction about the second axis;

controlling the first driving module to drive the camera to rotate reversely by a first angle component;

and controlling the second driving module to drive the first support to reversely rotate by a second angle component.

The technical scheme adopted by the invention can achieve the following beneficial effects:

the camera module disclosed by the embodiment of the invention improves the structure of the existing camera module, so that the camera can rotate around the first axis, the angle compensation can be carried out in the direction of rotating around the first axis according to the inclination angle of the camera module, moreover, the whole formed by the camera and the first support can carry out the angle compensation in the direction of rotating around the second axis relative to the base, finally, the adaptive angle compensation can be carried out on the inclination angle of the camera module, and the adverse effect of shaking on shooting can be prevented.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the invention and not to limit the invention. In the drawings:

fig. 1 is an exploded schematic view of a camera module according to an embodiment of the present invention;

fig. 2 is a schematic structural diagram of a camera module disclosed in the embodiment of the present invention;

fig. 3 is a schematic flow chart of a control method of a camera module according to an embodiment of the present invention.

Description of reference numerals:

100-first bracket, 110-first articulated shaft, 120-second articulated shaft,

200-camera,

300-a base, 310-a second hinge hole,

400-a first driving module, 410-a first magnet, 420-a first driving coil, 430-a first Hall device,

500-a second driving module, 510-a second magnet, 520-a second driving coil, 530-a second Hall device,

600-second support, 610-avoidance hole, 620-connection hole.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the technical solutions of the present invention will be clearly and completely described below with reference to the specific embodiments of the present invention and the accompanying drawings. It is to be understood that the described embodiments are merely exemplary of the invention, and not restrictive of the full scope of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The technical solutions disclosed in the embodiments of the present invention are described in detail below with reference to the accompanying drawings.

Referring to fig. 1 and 2, an embodiment of the invention discloses a camera module, which is suitable for an electronic device. The camera module disclosed in the embodiment of the present invention includes a first bracket 100, a camera 200, a base 300, a first driving module 400, and a second driving module 500.

The first bracket 100 is used for mounting the camera 200, and the camera 200 is rotatably connected with the first bracket 100, so that the camera 200 and the first bracket 100 can rotate relatively. There are various ways to realize the rotational connection of the camera 200 and the first bracket 100, for example, the first bracket 100 may be provided with a first hinge hole, the first bracket 100 may be provided with a first hinge shaft 110, the first hinge shaft 110 is in hinge fit with the first hinge hole, and the camera 200 may be connected to the first hinge shaft 110, so that the camera 200 and the first hinge shaft 110 rotate together relative to the first hinge hole, and finally, the rotational connection of the camera 200 relative to the first bracket 100 is realized. Specifically, the camera head 200 may be fixedly connected to the first hinge shaft 110.

In order to facilitate the installation of the camera 200, in a general case, the camera module may further include a second bracket 600, the camera 200 is fixedly connected to the second bracket 600, and the second bracket 600 is hinged to the first bracket 100, so that the second bracket 600 drives the camera 200 to rotate together relative to the first bracket 100. In this case, the camera 200 is rotatably coupled to the first stand 100 through the second stand 600.

Similarly, the second support 600 has a plurality of with first support 100 normal running fit's mode, can realize through the cooperation of first articulated shaft 110 with first articulated hole at camera 200 and rotate with first support 100 under the prerequisite of being connected, camera 200 is fixed on second support 600, and second support 600 links to each other with first articulated shaft 110 is fixed to realize that the whole that second support 600 and camera 200 formed rotates for first support 100. Specifically, the second bracket 600 may be provided with a connection hole 620, and the connection hole 620 may be fixedly connected to the first hinge shaft 110, thereby implementing the connection of the second bracket 600 and the first hinge shaft 110.

The base 300 is used for mounting the first bracket 100, and the first bracket 100 is rotatably connected with the base 300, in this case, the camera 200 can be rotatably connected with the base 300 through the first bracket 100, and finally can rotate relative to the base 300.

Specifically, the first bracket 100 may be provided with a second hinge shaft 120, and specifically, the first bracket 100 is fixedly connected with the second hinge shaft 120. The base 300 may be formed with a second hinge hole 310, and the second hinge shaft 120 is hinged to the second hinge hole 310 to finally form a revolute pair. In this case, the first bracket 100 is rotatably coupled to the base 300 by the engagement of the second hinge shaft 120 with the second hinge hole 310.

Based on that the tilt angle of the camera module generates two angle components in the plane where the camera module is located, in the embodiment of the present invention, the first driving module 400 drives the camera 200 to rotate around the first axis according to the tilt angle of the camera module, so as to adjust the angle component in the direction around the first axis. In a case where the camera head 200 is rotatably coupled to the first bracket 100 by the first hinge shaft 110, the axis of the first hinge shaft 110 is a first axis.

Similarly, the second driving module 500 drives the first bracket 100 to rotate around the second axis according to the inclination angle of the camera module, so as to adjust the angular component in the direction around the second axis. In the embodiment of the present invention, the first axis intersects with the second axis or is out of plane, that is, the first axis and the second axis are intersecting straight lines or out of plane straight lines. In a case where the first bracket 100 is rotatably coupled to the base 300 by the second hinge shaft 120, the axis of the second hinge shaft 120 is a second axis. In a preferred embodiment, the first axis is perpendicular to the second axis, thereby facilitating the calculation of the angular component.

In this case, under the driving action of the first driving module 400 and the second driving module 500, the angle compensation of the camera 200 can be finally realized in two rotation directions, so as to compensate for the inclination angle caused by the shake. It should be noted that the directions in which the first driving module 400 and the second driving module 500 drive the camera 200 to rotate are opposite to the directions of the corresponding angular components, so as to compensate for the tilt of the camera module.

The camera module disclosed by the embodiment of the invention improves the structure of the existing camera module, so that the camera 200 can rotate around the first axis, the angle compensation can be carried out in the direction of rotating around the first axis according to the inclination angle of the camera module, moreover, the whole formed by the camera 200 and the first bracket 100 can carry out the angle compensation in the direction of rotating around the second axis relative to the base 300, finally, the adaptive angle compensation can be carried out according to the inclination angle of the camera module, and finally, the adverse effect of shaking on shooting can be prevented.

The camera module disclosed by the embodiment of the invention can comprise an angle detection device, wherein the angle detection device is used for detecting the inclination angle of the camera module, under the normal condition, in the process of shooting by a user through handheld electronic equipment, the whole electronic equipment shakes to cause the camera module to shake, and the camera module shakes consistently with the whole electronic equipment, so that the angle detection device detects the inclination angle of the camera module caused by shaking, and the inclination angle of the whole electronic equipment can be detected substantially. In the embodiment of the present invention, the angle detecting device may be a gyroscope, or may be another device capable of detecting an angle, such as a hall angle sensor. Specifically, the angle detection device may be mounted on a main board of the electronic apparatus, or may be mounted on a component of the camera module.

In the embodiment of the present invention, the first driving module 400 may be of various types as long as the camera 200 can be driven to rotate around the first axis. Referring to fig. 1 again, the embodiment of the invention discloses a specific first driving module 400, and the disclosed first driving module 400 may include a first magnet 410 and a first driving coil 420, one of the first magnet and the first driving coil 420 may be disposed on the camera 200, and the other may be disposed on the first bracket 100. The camera head 200 is rotated with respect to the first bracket 100 by the engagement of the first magnet 410 and the first driving coil 420. Specifically, the first magnet 410 may be a permanent magnet or an electromagnet.

Of course, in a case where the camera head 200 is rotatably coupled to the first bracket 100 through the second bracket 600, one of the first magnet 410 and the first driving coil 420 may be disposed on the second bracket 600 and the other may be disposed on the first bracket 100. In this case, the first magnet 410 or the first driving coil 420 is indirectly connected to the camera head 200 through the second holder 600. In this case, the second bracket 600 rotates relative to the first bracket 100 by the cooperation of the first magnet 410 and the first driving coil 420, so that the adjustment about the first axial direction is achieved, and the angular component generated by the inclination in the direction is compensated.

In a specific working process, a magnetic field is generated after the first driving coil 420 is powered on, and the magnetic field generated in the powered state of the first driving coil 420 and the first magnet 410 generate a first magnetic field force, so that the camera 200 rotates relative to the first bracket 100 under the driving of the first magnetic field force, and finally the driving purpose is achieved.

Specifically, the first magnet 410 may be fixed to the camera head 200 or the second bracket 600, and accordingly, the first driving coil 420 may be fixed to the first bracket 100. Of course, it may also be: the first magnet 410 is fixed to the first bracket 100, and accordingly, the first driving coil 420 is fixed to the camera head 200 or the second bracket 600.

In order to better control the rotation of the camera 200 around the first axis, in a preferred embodiment, the first driving module 400 disclosed in the embodiment of the present invention may further include a first hall device 430, one of the first hall device 430 and the first magnet 410 is connected to the camera 200, and the other is connected to the first bracket 100, in a specific detection process, the first magnet 410 and the first hall device 430 rotate relatively, and the first hall device 430 achieves the purpose of detecting the rotation angle according to the detected change of the magnetic field. The first hall device 430 may detect a first rotation angle of the camera 200, an angle component of an inclination angle of the camera module in a direction in which the camera 200 rotates about the first axis is a first angle component, and the first driving coil 420 is deenergized under a condition that the first rotation angle is opposite to and equal to the first angle component, thereby stopping the rotation of the camera 200 with respect to the first bracket 100.

Specifically, both the first hall device 430 and the first driving coil 420 may be mounted on the first bracket 100, and the first magnet 410 is disposed on the camera head 200. In a more preferable embodiment, the first hall device 430 and the first driving coil 420 may be respectively disposed on two sides of the first axis, so as to improve the balance of the camera 200 on the two sides of the first axis and avoid adverse effects caused by an imbalance.

As shown in fig. 1, in the case where the camera head 200 is hinge-coupled to the first bracket 100 by the first hinge shaft 110, both the first magnet 410 and the camera head 200 may be connected to the first hinge shaft 110, in which case the first magnet 410 is connected to the camera head 200 by the first hinge shaft 110. Specifically, the first magnet 410 and the camera head 200 may be fixed at both ends of the first hinge shaft 110, respectively.

Similarly, the second driving module 500 may be of various types as long as it can drive the first bracket 100 to rotate around the second axis. Referring to fig. 1 again, the embodiment of the invention discloses a specific second driving module 500, the disclosed second driving module 500 may include a second magnet 510 and a second driving coil 520, one of the second magnet 510 and the second driving coil 520 may be disposed on the first bracket 100, the other may be disposed on the base 300, and the first bracket 100 rotates relative to the base 300 through the cooperation of the second magnet 510 and the second driving coil 520, so as to achieve the purpose of adjusting the corresponding angle component in the direction around the second axis. Specifically, the second magnet 510 may be a permanent magnet or an electromagnet.

In a specific working process, a magnetic field is generated after the second driving coil 520 is powered on, and the magnetic field generated in the powered state of the second driving coil 520 and the second magnet 510 generate a second magnetic field force, so that the whole body formed by the first bracket 100 and the camera 200 rotates relative to the base 300 under the action of the second magnetic field force, and finally the driving purpose is achieved.

Specifically, the second magnet 510 may be fixed to the first bracket 100, and accordingly, the second driving coil 520 may be fixed to the base 300. Of course, it may also be: the second magnet 510 is fixed to the base 300, and accordingly, the second driving coil 520 is fixed to the first bracket 100.

In order to better control the rotation of the first bracket 100 relative to the base 300, in a preferred embodiment, the second driving module 500 disclosed in the embodiment of the present invention may further include a second hall device 530, one of the second hall device 530 and the second magnet 510 is disposed on the first bracket 100, and the other one is disposed on the base 300, so as to be capable of relatively rotating along with the relative rotation between the first bracket 100 and the base 300, in a specific detection process, the second magnet 510 and the second hall device 530 relatively rotate, and the second hall device 530 achieves the purpose of detecting the rotation angle according to the detected change of the magnetic field. The second hall device 530 may detect a second rotation angle of the first bracket 100, an angle component of the tilt angle of the camera module in the direction in which the first bracket 100 rotates about the second axis is a second angle component, and the second driving coil 520 is powered off under the condition that the second rotation angle is opposite to and equal to the second angle component, thereby stopping the rotation of the first bracket 100.

In a specific implementation manner, the electronic device disclosed in the embodiment of the present invention may further include a controller, the controller is connected to the first driving coil 420 and the second driving coil 520, and the controller can control the first driving coil 420 and the second driving coil 520 to be powered off.

For more convenient control, corresponding controllers may be respectively configured for the first driving coil 420 and the second driving coil 520, and based on this, in a preferable scheme, the electronic device disclosed in the embodiment of the present invention may further include a first controller, the first controller is connected to the first driving coil 420, and the first controller can control the first driving coil 420 to be powered off. Similarly, the electronic device disclosed in the embodiment of the present invention may further include a second controller, where the second controller is connected to the second driving coil 520, and the second controller is capable of controlling the second driving coil 520 to be powered off.

Of course, the controller is not limited to controlling the power-off, and may control the power-on of the first and second driving coils 420 and 520.

Specifically, both the second hall device 530 and the second driving coil 520 may be mounted on the first bracket 100, and the second magnet 510 is disposed on the base 300. In a more preferable embodiment, the second hall device 530 and the second driving coil 520 may be respectively disposed at two sides of the second axis, so that the balance of the whole formed by the first bracket 100 and the camera 200 at two sides of the second axis can be improved, and adverse effects caused by an unbalanced weight can be avoided.

It should be noted that, in the embodiment of the present invention, the processes and principles of the first hall device 430 detecting the first rotation angle and the second hall device 530 detecting the second rotation angle are well known technologies, and are not described herein again.

Referring to fig. 1 again, the second bracket 600 disclosed in the embodiment of the present invention may be a cover-shaped structural member, which is covered on the camera 200, so as to protect the camera 200. Specifically, the second bracket may be provided with an avoiding hole 610, so that the camera 200 partially passes through the avoiding hole to perform photographing. Of course, the camera 200 is mounted on the second bracket 600 without affecting the rotation of the camera 200 with respect to the first bracket 100. In order to facilitate the rotation of the camera 200, the top end of the camera 200 may be fixedly connected to the second bracket 600, and the bottom end of the camera 200 is in a suspended state, so as to further reduce the probability of the camera 200 being interfered.

In a preferred embodiment, the first bracket 100 may be a frame-type structure, and the camera 200 may be disposed in an area surrounded by the first bracket, so as to be protected by the first bracket 100. Similarly, the base 300 may be a frame-type structure, and the first bracket 100 may be disposed inside the base 300 so as to be protected by the base 300. The second magnet 510 may be fixed on the inner wall of the base 300, provided that the base 300 is a frame-type structural member.

Based on the camera module disclosed by the embodiment of the invention, the embodiment of the invention discloses electronic equipment, and the disclosed electronic equipment comprises the camera module.

The electronic equipment disclosed by the embodiment of the invention can be a smart phone, a tablet computer, an electronic book reader, wearable equipment and the like, and the embodiment of the invention does not limit the specific types of the electronic equipment.

Based on the camera module disclosed in the embodiment of the present invention, the embodiment of the present invention discloses a control method of a camera module, which is applied to an electronic device, please refer to fig. 3, and the disclosed control method includes:

s101, obtaining the inclination angle of the camera module.

The inclination angle of the electronic device can be detected by an angle detection device of the electronic device. Because the module of making a video recording is installed in electronic equipment and does not have relative rotation with electronic equipment, can obtain the inclination of the module of making a video recording through the inclination that detects electronic equipment. The tilt angle may be a shake caused by photographing. The angle detection means may be a sensor that can detect an angle, such as a gyroscope or a gravity sensor in the electronic device.

S102, determining a first angle component of the inclination angle in the direction around the first axis and a second angle component of the inclination angle in the direction around the second axis.

The angle detection device is preset with a coordinate system, the first axis is used as an X axis, the second axis is used as a Y axis, and the offset angle of the X axis and the offset angle of the Y axis are determined through the coordinate system, so that the first angle component and the second angle component are obtained. In the photographing process, imaging blur is caused by photographing shake caused by holding the electronic device with a hand. The amount of jitter can be determined by the first angle component and the second angle component, and the direction of tilt can be determined by the offset direction.

S103, controlling the first driving module 400 to drive the camera 200 to rotate reversely by the first angle component.

The first driving module 400 is controlled by the processor of the electronic device to drive the camera 200 to shift in the X-axis direction, the shift amount of the camera 200 in the X-axis is the same as the first component of the tilt angle, and the shift direction is opposite to the shift direction of the tilt angle in the X-axis direction, so that the influence of the shake in the X-axis direction of the electronic device is counteracted.

And S104, controlling the second driving module 500 to drive the first support 100 to rotate reversely by a second angle component.

The second driving module 500 is controlled by the processor of the electronic device to drive the first bracket 100 to shift, the shift amount of the first bracket 100 on the Y axis is the same as the second component of the tilt angle, and the shift direction is opposite to the shift direction of the tilt angle on the Y axis, so that the influence of the shake on the electronic device in the Y axis direction is counteracted.

Specifically, in the control method, the sequence of step S103 and step S104 may be partially sequential. The corresponding implementation process of each step of the control method may refer to the corresponding implementation process in the above embodiment of the camera module, and is not described herein again.

In the above embodiments of the present invention, the difference between the embodiments is mainly described, and different optimization features between the embodiments can be combined to form a better embodiment as long as they are not contradictory, and further description is omitted here in view of brevity of the text.

The above description is only an example of the present invention, and is not intended to limit the present invention. Various modifications and alterations to this invention will become apparent to those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the scope of the claims of the present invention.