Patent Publication Number: US-2021195006-A1

Title: Mobile terminal

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation-in-part of International Application No. PCT/CN2019/095800 filed on Jul. 12, 2019, which claims priority to Chinese Application No. 201821459213.0 filed on Sep. 6, 2018. The entire contents of the aforementioned applications are incorporated by reference herein. 
    
    
     TECHNICAL FIELD 
     The present disclosure relates to the field of mobile terminal technologies, and more particularly, to a mobile terminal. 
     BACKGROUND 
     Mobile terminals (phones, tablets, etc.) are generally equipped with cameras, which are configured to provide functions such as video calling and shooting. However, shooting scenarios of the camera is relatively monotonous. 
     SUMMARY 
     Based on the above, the disclosure provides a mobile terminal. 
     A mobile terminal includes a terminal device, an image capturing device and a locking mechanism. 
     The terminal device comprises a display screen, a first power supply module, and a first wireless communication module, wherein the first power supply module is configured to supply power to the display screen and the first wireless communication module, and the terminal device defines a mounting recess on a side thereof facing away from a display area of the display screen. 
     The image capturing device comprises a casing, a camera module, a second power supply module, and a second wireless communication module, wherein the second power supply module is configured to supply power to the camera module and the second wireless communication module, the camera module and the second power supply module are arranged in the casing, the camera module has a light incident surface exposed from the casing; the image capturing device is configured to be mounted in the mounting recess, thereby making the light incident surface be exposed on the side facing away from the display area; the casing is provided with an engaging slot. 
     The locking mechanism comprises a transmission member and a bolt, and the transmission member is rotatably mounted on the terminal device and abuts against the bolt. The locking mechanism has a lock state and a released state, the bolt is engaged with the engaging slot and the image capturing device is locked to the terminal device when the locking mechanism is in the lock state, the bolt exits from the engaging slot and the image capturing device is detachable from the mounting recess when the locking mechanism is in the released state; wherein the second wireless communication module is communicatively connected with the first wireless communication module when the locking mechanism is in the released state. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In order to more clearly describe the technical solutions of the disclosure, the following briefly introduces the drawings needed to be used in the description of the embodiments. Obviously, the drawings in the following description only illustrate some embodiments of the disclosure, and other drawings can be obtained for those skilled in the art, based on these drawings without any creative work. 
         FIG. 1  is a perspective view of a mobile terminal, wherein an image capturing device is mounted on a terminal device according to an embodiment; 
         FIG. 2  is another perspective view of the mobile terminal as shown in  FIG. 1 ; 
         FIG. 3  is a perspective view showing the image capturing device being disassembled from the terminal device; 
         FIG. 4  is a block diagram of the image capturing device and the terminal device of  FIG. 1 ; 
         FIG. 5  is an exploded view of the image capturing device of the mobile terminal shown in  FIG. 3 ; 
         FIG. 6  is a perspective view of the image capturing device of the mobile terminal shown in  FIG. 5  without a casing; 
         FIG. 7  is a schematic front view showing a locking mechanism of the mobile terminal shown in  FIG. 2  is at a first position; 
         FIG. 8  is an enlarged view of a portion A of the mobile terminal shown in  FIG. 7 ; 
         FIG. 9  is a schematic view showing the locking mechanism at a second position; 
         FIG. 10  is a schematic diagram showing an application scene of the imaging capturing device of the mobile terminal shown in  FIG. 3 ; 
         FIG. 11  is a front view of the locking mechanism of the mobile terminal shown in  FIG. 6  being covered with a cover plate. 
     
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     In order to facilitate the understanding of the disclosure, the following will make a more comprehensive description of the disclosure with reference to the relevant drawings. The drawings illustrate preferred embodiments of the disclosure. However, this disclosure can be implemented in many different manners and is not limited to the following described embodiments. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure more thorough and comprehensive. 
     The wording “terminal device” refers to, but is not limited to, a device capable of receiving and/or sending communication signals via one or more of the following communicating ways: 
     (1) via wired lines, such as Public Switched Telephone Networks (PSTN), Digital Subscriber Lines (DSL), digital cables, and direct cable connections; 
     (2) via a wireless interface, such as a cellular network, a Wireless Local Area Network (WLAN), a digital TV network (e.g., DVB-H network), a satellite network, a AM-FM broadcast transmitter. 
     A terminal device, which is configured to communicate through a wireless interface, may be referred to as a “mobile terminal”. Examples of the mobile terminal include but are not limited to the following electronic devices: 
     (1) a satellite phone or a cellular phone; 
     (2) Personal Communications System (PCS) terminals, capable of integrating cellular radio telephones, data processing and fax, and data communicating capabilities; 
     (3) a radio telephone, a pager, an Internet/Intranet access, a Web browser, a notebook, a calendar, a personal digital assistants (PDA) equipped with a Global Positioning System (GPS) receiver; 
     (4) a conventional laptop and/or palmtop receiver; 
     (5) a conventional laptop and/or palmtop radio telephone transceiver; etc. 
     In the embodiment as illustrated in  FIG. 1  to  FIG. 4 , a mobile terminal  10  is a smart phone. The mobile terminal  10  includes a terminal device  100 , an image capturing device  200  and a locking mechanism  300 . The terminal device  100  includes a display screen  120 , a first power supply module  160 , and a first wireless communication module  170 . The first power supply module  160  is configured to supply power to the display screen  120  and the first wireless communication module  170 . The first display screen  120  is configured to display information and provide an interactive interface for a user. The terminal device  100  defines a mounting recess  130  at one side which is facing away a display area  121  of the display screen  120 . As illustrated in FIG.  4  to  FIG. 6 , the image capturing device  200  includes a casing  210 , a camera module  220 , a second power supply module  230 , and a second wireless communication module  270 . The second power supply module  230  is configured supply power to the camera module  220  and the second wireless communication module  270 . The camera module  220  and the second power supply module  230  are arranged in the casing  210 . The camera module  220  has a light incident surface  221 , which is exposed from the casing  210 . Ambient lights can pass through the light incident surface  221  and enter into a photosensitive element of the camera module  220 . The image capturing device  200  can be installed in the mounting recess  130 , thereby enabling the light incident surface  221  to be exposed on the side facing away from the display area  121  of the display screen  120 . The casing  210  is provided with an engaging slot  211 . Referring to  FIG. 7  to  FIG. 9 , the locking mechanism  300  includes a transmission member  310  and a bolt  320 , and the transmission member  310  is rotatably connected to the terminal device  100  and abuts against the bolt  320 . The transmission member  310  is capable of rotating relative to the terminal device  100 , the bolt  320  is capable of selectively moving to a first position and/or a second position, and the locking mechanism  300  accordingly has a lock state and/or a released state. Referring to  FIG. 8 , at the first position, the bolt  320  is engaged with the engaging slot  211  and the image capturing device  200  is locked to the terminal device  100 . At the second position as illustrated in  FIG. 9 , the bolt  320  exits from the engaging slot  211  and the image capturing device  200  is capable of being detached/disassembled from the mounting recess  130 . When the image capturing device  200  is capable of being detached/disassembled from the mounting recess  130 , the second wireless communication module  270  is still communicatively connected with the first wireless communication module  170 , thereby achieving the communication between the image capturing device  200  and the terminal device  100 . 
     The first wireless communication module  170  and the second communication module  270  are configured for data transmission between the terminal device  100  and the image capturing device  200 . The first wireless communication module  170  and the second wireless communication module  270  may utilize Near Field Communication technology, and the first wireless communication module  170  and the second wireless communication module  270  use the same communication protocol. For example, the first wireless communication module  170  and the second wireless communication module  270  both may be Bluetooth communication modules, or both may be Wireless Fidelity (Wi-Fi) communication modules, or both may be Infrared Data (IrDA) communication modules, or both may be ZigBee communication modules, or both may be Ultra WideBand, or both may be Near Field Communication (NFC) modules, etc. In an alternative embodiment, the terminal device  100  may include a third wireless communication module, which is configured to communicate with an external device such as a base station or another mobile terminal  10 , thereby facilitating communication between more than one mobile terminals  10 . 
     When the image capturing device  200  is locked in the mounting recess  130 , the image capturing device  200  may communicate with the first wireless communication module  170  by the second wireless communication module  270 , and the camera module  220  at this time can perform functions as a rear camera. A user can perform remote shooting, video recording and other operations through the image capturing device  200 . When the image capturing device  200  is detached from the mounting recess  130 , the second wireless communication module  270  can still communicate with the first wireless communication module  170 , and the user at this time can use the image capturing device  200  to shoot with any direction in any scene. 
     In the above mobile terminal  10 , the image capturing device  200  not only can be installed in the mounting recess  130  but also can be released from the mounting recess  130 . After the image capturing device  200  is taken out from the mounting recess  130 , the image capturing device  200  communicates with the first wireless communication module  170  of the terminal device  100  through the second wireless communication module  270 , and the user can use the image capturing device  200  to shoot in multiple directions and multiple scenarios. In the embodiment as illustrated in  FIG. 9 , the user can hold the image capturing device  200  with one hand and the terminal device  100  with the other hand, so the user can capture images at various positions and directions through the image capturing device  200 , and view the images through the display screen  120  of the terminal device  100 . In an alternative embodiment, the user may dispose the image capturing device  200  in a certain place, and view the images captured by the image capturing device  200  through the terminal device  100  in another place. Since the image capturing device  200  can be taken out from the terminal device  100  and maintain in communication with the terminal device  100  after being taken out, the terminal device  100  does not need to provide a front camera on the side that the display screen  120  locates, so the screen-to-body ratio of the terminal device  100  can be increased. For example, the screen-to-body ratio of the terminal device  100  with the above structure may be more than 85%. It can be understood that, the arrangement of the locking mechanism  300  can reliably fix the image capturing device  200  in the mounting recess  130  and can prevent the image capturing device  200  from easily falling out of the mounting recess  130 . When the locking mechanism  300  releases the locking to the image capturing device  200 , the image capturing device  200  can be taken out of the mounting recess  130 , thereby facilitating the usage for the user. 
     In the embodiments as illustrated in  FIG. 1  and  FIG. 2 , the terminal device  100  is substantially in a shape of cuboid. The mobile terminal  10  includes a rear wall  111  and side walls connected to outer peripheries of the display screen  120 . The rear wall  111  is located at the side facing away from the display area  121  and connected to the side walls. The side walls include a left side wall  112 , a right side wall  114  opposite to the left side wall  112 , a top side wall  116 , and a bottom side wall  118  opposite to the top side wall  116 . Each of the left side wall  112  and the right side wall  114  are located between the top side wall  116  and the bottom side wall  118 . Each of the top side wall  116  and the bottom side wall  118  are located between the left side wall  112  and the right side wall  114 . The mounting recess  130  penetrates through the rear side wall  111 . The mounting recess  130  is located between the left side wall  112  and the right side wall  114 , and also is located between the top side wall  116  and the bottom side wall  118 . In one embodiment, the mobile terminal  10  is provided with two locking mechanisms  300 , one is located adjacent to the left side wall  112 , and the other is located adjacent to the right side wall  114 . In the following, the locking mechanism  300  located adjacent to the right side wall  114  is taken as an example for description. However, it can be understood that there may be only one locking mechanism  300  included in the mobile terminal  10 . 
     In one embodiment, the rear wall  111  and the side walls may consist a rear cover, in other words, the rear cover includes the rear wall  111  and the side walls. In another embodiment, the rear wall  111  may consist a rear cover while the side walls may consist a middle frame of the terminal device  10 , in other words, the terminal device  100  may include a rear cover consisting the rear wall and a middle frame consisting the side walls. 
     The terminal device  100  may further include a middle plate  140 , the middle plate  140  is positioned between the display screen  120  and the rear wall  111 . The transmission member  310  is rotatably connected to the middle plate  140 , and the bolt  320  is slidably coupled to the middle plate  140 . The middle plate  140  can be integrally formed with the side walls, or can be detachably connected with the side walls. Using the middle plate  140  to support the bolt  320  and the transmission member  310  can improve the structural stability of the locking mechanism  300 . 
     The locking mechanism  300  includes a pressing block  330 , which includes a block body  331  and a limit part  333  integrally formed with the block body  331 . One of the side walls is provided with an installation hole  101 , the block body  331  engages with the installation hole  101 . The limit part  333  is positioned between the side wall and the transmission member  310 , and the side wall and the transmission member  310  can abut the limit part  333  respectively. The pressing block  330  can press the transmission member  310  thereby enabling the transmission member  310  to be rotatable relative to the middle plate  140 . In one embodiment, the user presses the pressing block  330 , the pressing block  330  presses the transmission member  310 , and the transmission member  310  rotates relative to the middle plate  140 , so that the bolt  320  can be driven to slide relative to the middle plate  140 , meanwhile the bolt  320  is enabled to be capable of being exited from the engaging slot  211 . It can be understood that the pressing block  330  is not necessary in the disclosure. As an exemplary alternative embodiment, the transmission member  310  may protrude out and be exposed from the installation hole  101 , so the bolt  320  can also be exited from the engaging slot  211  when the user pressing a protruding portion of the transmission member  310 . The pressing block  330  may be a press button in some embodiments. 
     In one embodiment, the locking mechanism  300  further includes an elastic member  340 . One end of the elastic member  340  abuts against the middle plate  140 , and the other end of the elastic member  340  abuts against the transmission member  310 . The elastic member  340  can press the limit part  333  via the transmission member  310 , thereby making the limit part  333  abut against one side wall and the block body  331  protrude from an outer surface of said side wall. Disposing the elastic member  340  can facilitate the return of the pressing block  330  and the bolt  320 , so the bolt  320  can be inserted into or exited from the mounting recess  130 , the outer surface of the block body  331  can be protruded from the sidewall to facilitate the user to press the pressing block  330 , and thereby facilitating the detachment of the image capturing device  200  from the mounting recess  130 . The elastic member  340  may be a spring, an elastic piece, an elastic column, or the like. The elastic member  340  can be compressed under the pressing of the transmission member  310 . When the pressing block  330  is released, the elastic member  340  can push the pressing block  330  back. It can be understood that the elastic member  340  is not necessary in the disclosure, as in an exemplary alternative embodiment, a structure such as a pull rod may be provided to push the transmission member  310  back into position. 
     As illustrated in  FIG. 8 , the bolt  320  is provided with a notch  321 . The transmission member  310  includes a first end  311  and a second end  313 . The first end  311  abuts against the limit part  333 , and the second end  313  is received in the notch  321  and rotatable relative to the bolt  320 . Specifically, a cross-section of the second end  313  is arc-shaped, and the second end  313  may be substantially spherical. During the rotation of the transmission member  310  relative to the middle plate  140 , the second end  313  is received in the notch  321  and can rotate relative to the bolt  320 , thereby avoiding interference with the sliding of the bolt  320 . Such a structure facilitates the assembly of the transmission member  310  and the bolt  320 . It can be understood that the transmission member  310  can also be rotatably connected with the bolt  320  in an engagement form of a rotating shaft with a shaft hole, which will not be detailed here. 
     As illustrated in  FIG. 8  and  FIG. 9 , the transmission member  310  is rotatably mounted on the middle plate  140  through a rotating pivot  301 . Specifically, the transmission member  310  includes a first shaft portion  315  and a second shaft portion  317 , the second shaft portion  317  is connected to and substantially perpendicular to the first shaft portion  315 . The second shaft portion  317  is pivotally mounted on the middle plate  140  through the rotating pivot  301 . The first end  311  is positioned on the first shaft portion  315  and is away from the second shaft portion  317 . The second end  313  is positioned on the second shaft portion  317  and is away from the first shaft portion  315 . 
     The transmission member  310  may further include a supporting column  319 , which extends from the second shaft portion  317  and is adjacent to the image capturing device  200 . In other words, the first shaft portion  315  and the supporting column  319  both extend from the second shaft portion  317  towards opposite directions, the first shaft portion  315  extends toward the side wall, and the supporting column  319  extends toward the image capturing device  200 . A portion of the elastic member  340  is sleeved on the supporting column  319 , and the elastic member  340  is positioned between the second shaft portion  317  and an edge of the middle plate  140 . 
     The locking mechanism  300  has a first state and a second state, in other words, the lock state and the released state. In the first state as illustrated in  FIG. 8 , the second shaft portion  317  is substantially parallel to a length direction of the terminal device  100 , the bolt  320  is inserted into the engaging slot  211  of the image capturing device  200 , that is, the image capturing device  200  is locked to the terminal device  100 . In the second state, the pressing block  330  being pressed, the limit part  333  pushes the first end  311  to move closer to the image capturing device  200 , so the transmission member  310  is pushed to slightly rotate in a clockwise direction as illustrated in  FIG. 9 , then the second end  313  is driven to move away from the image capturing device  200 , and the bolt  320  is driven by the second end  313  to move away from the image capturing device  200 , finally the bolt  320  is exited from the engaging slot  211  and the image capturing device  200  is then released from the terminal device  100 , as illustrated in  FIG. 9 . 
     Correspondingly, the transmission member  310  also has an original position and a final position, the original position corresponds to the lock state, and the final position corresponds to the released state. The elastic member  340  also has an original state and a final state, the original state corresponds to the lock state, and the final state corresponds to the released state. In the original state, the elastic member  340  may be in a free state or may be compressed in a slightly compressed state. In the final state, the elastic member  340  is compressed to be in a compressed state or in a further compressed state. That is, a compressed deformation of the elastic member in the final state is greater than that of the elastic member in the original state. 
     It is noted that, a moving direction of the first end  311  is opposite to that of the second end  313 . When the user presses the block body  331 , the pressing block  330  and the first end  311  substantially move along a first direction, which is closer to the image capturing device  200 , meanwhile the bolt  320  and the second end  312  substantially move along a second direction, which is away from the image capturing device  200 , as illustrated in  FIG. 9 . 
     In particular, when the image capturing device  200  has been installed in the mounting recess  130  and it is required to be disassembled from the terminal device  100 , the user may press the pressing block  330 , thereby enabling the locking mechanism  300  to switch from the lock state to the released state. Specifically, when the user wants to disassemble the image capturing device  200  from the terminal device  100 , the user can press the block body  331 , then the limit part  333  presses the first end  311  of the transmission member  310 , the elastic member  340  is compressed and the transmission member  310  pivotally rotates relative to the middle plate  140  in a clockwise direction, then the second end  312  of the transmission member  310  moves in a direction opposite to that of the first end  311 , thereby driving the bolt  320  to move in a direction away from the image capturing device  200  and the mounting recess  130 . As such, the bolt  320  moves until it exits from the engaging slot  211 , which makes the locking mechanism  300  be in the released state. The user can take up the image capturing device  200  from the terminal device  100  under the released state. 
     It is noted that, if the user releases the pressing block  330 , the locking mechanism  300  will be restored to the lock state. That is, when the pressing block  330  is pressed, the locking mechanism  300  switches to the released state, and when the pressing block  330  is released, the locking mechanism  300  switches to the lock state. 
     Correspondingly, when the image capturing device  200  is needed to be mounted in the mounting recess  130  or the user wants to install the image capturing device  200  onto the terminal device  100 , the user can press the pressing block  330  again, the locking mechanism  300  switches to the released state, then the image capturing device  200  can be mounted in the mounting recess  130 . After the image capturing device  200  has been successfully mounted in the mounting recess  130 , the user can release the pressing block  330 , so the locking mechanism  300  switches to the lock state and locks the image capturing device  200  to the terminal device  100 . 
     In one embodiment as illustrated in  FIG. 8 , the middle plate  140  is provided with a sliding groove  141 , and the bolt  320  is engaged with and partially provided in the sliding groove  141 . Referring to  FIG. 11 , the terminal device  100  further includes a cover plate  150  detachably coupled to the middle plate  140 , and the cover plate  150  covers the sliding groove  141 . The bolt  320  slides in the sliding groove  141 , the sliding groove  141  and the cover plate  150  can guide and limit the sliding of the bolt  320 , which is beneficial to a smooth movement of the bolt  320 . Such a structure also facilitates the assembly and disassembly of the cover plate  150  and the middle plate  140 . 
     Referring to  FIG. 5  and  FIG. 6 , the image capturing device  200  is substantially in a shape of a cuboid. The casing  210  includes a front end surface  213 , a rear end surface  215  opposite to the front end surface  213 , and side end surfaces connected between the front end surface  213  and the rear end surface  215 . The side end surfaces include a left end surface  212 , a right end surface  214  opposite to the left end surface  212 , a top end surface  216 , and a bottom end surface  218  opposite to the top end surface  216 . Each of the left end surface  212  and the right end surface  214  is located between the top end surface  216  and the bottom end surface  218 , and each of the top end surface  216  and the bottom end surface  218  is located between the left end surface  212  and the right end surface  214 . The light incident surface  221  is exposed on the front end surface  213 , and the engaging slot  211  is provided in the left end surface  212  and the right end surface  214 . For example, the engaging slot  211  may be a through slot penetrating through the left end surface  212  and the right end surface  214 . For another example, the image capturing device  200  may defines two engaging slots  211  respectively exposed from the left end surface  212  and the right end surface  214 , that is, the two engaging slots  211  each are blind slots. When the mobile terminal  10  includes two locking mechanisms  300 , the bolt  320  of one locking mechanism  300  engages with one engaging slot  211  of the image capturing device  200 , while the bolt  320  of the other locking mechanism  300  engages with the other engaging slot  211  of the image capturing device  200 . When the image capturing device  200  is mounted in the mounting recess  130 , the front end surface  213  can be flush with an outer surface of the rear wall  111 . Thus, after the image capturing device  200  with such a structure is installed in the mounting recess  130 , the mobile terminal  10  can maintain a high overall appearance consistency. In one embodiment, the light incident surface  221  protrudes from the front end surface  213 . With such a structure, the portion that the light incident surface  221  of the image capturing device  200  is located, can have a relatively thicker thickness, while other portions of the image capturing device  200  can be made relatively thinner. Therefore, it is beneficial to the lightness and thinness of the image capturing device  200 , which in turn is beneficial to the lightness and thinness of the mobile terminal  10 . 
     As one embodiment, the image capturing device  200  may include one or more module contacts, and the terminal device  100  includes one or more device contacts. When the image capturing device  200  is installed in the mounting recess  130 , the module contacts can be in contact with the device contacts respectively, so that the terminal device  100  can charge the image capturing device  200 . Such a structure facilitates the terminal device  100  to charge the image capturing device  200  and is beneficial for the image capturing device  200  to retain sufficient power for the convenience of the user. It is understood that the module contacts and/or the device contacts may be metal contacts, and the module contacts and the device contacts may have various structural forms. For example, the image capturing device  200  may define small holes and metal contacts can be respectively installed therein as the module contacts, the terminal device  100  can be provided with protruding metal contacts as the device contacts, thereby realizing the charging of the terminal device  100  to the image capturing device  200  through the cooperation of the module contacts and the device contacts. 
     Referring to  FIG. 5  and  FIG. 6 , a module main board  240  is provided in the casing  210 . The front end surface  213  of the casing  210  is provided with a light exit hole  217 , and the light incident surface  221  is exposed from the light exit hole  217 . The second power supply module  230  is stacked on the module main board  240  and can supply power to the module main board  240 . The module main board  240  can respectively communicate with the camera module  220  and the second wireless communication module  270 . The module main board  240  may include a circuit board and a number of electronic components connected to the circuit board. The module main board  240  is configured to process image information captured by the camera module  220  and send it to the terminal device  100  through the second wireless communication module  270 . The module main board  240  is substantially U-shaped and defines a gap  241  thereby. The camera module  220  includes a lens barrel  223 , and the lens barrel  223  penetrates the gap  241 . Such a design can avoid stacking the lens barrel  223  on the module main board  240 , thereby making internal components in the image capturing device  200  be more compact arrange, it is beneficial to reduce a thickness of the image capturing device  200 . 
     Furthermore, the second power supply module  230  is provided with a through hole  231 , so the second power supply module  230  is substantially annular. The through hole  231  communicates with the gap  241 , and the lens barrel  223  penetrates the through hole  231  and the gap  241  thereby receiving in the through hole  231  and the gap  241 . Such a structure can avoid stacking the lens barrel  223  on the second power supply module  230 , thus making the arrangement of internal components in the image capturing device  200  be more compact, and reducing the thickness of the image capturing device  200 . It can be understood that the first power module and the second power supply module  230  each include a battery that can be repeatedly charged and discharged, such as a lithium battery. In other embodiments, the first power module and the second power supply module  230  each may also be a fuel cell or other batteries, and the second power supply module  230  may be connected to the module main board  240  through a power flexible printed circuit board, thereby enabling the second power supply module  230  supply power to the module main board  240 , and details are not repeated here. 
     Technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, all possible combinations of the various technical features in the above-mentioned embodiments are not described. However, as long as there is no contradiction in the combination of these technical features, any combination should be considered as the scope of this specification. 
     The above-mentioned embodiments only describe several embodiments of the disclosure, and the description is relatively specific and detailed, but it should not be understood as a limitation on the scope of the disclosure. It should be pointed out that for those of ordinary skill in the art, modifications and improvements can be made without departing from the concept of this disclosure, and these should fall within the protection scope of this disclosure. Therefore, the scope of protection of this disclosure shall be subject to the appended claims.