Patent Publication Number: US-2022238391-A1

Title: Device and system for testing flatness

Description:
CROSS-REFERENCES TO RELATED APPLICATIONS 
     This patent application claims the priority of the Chinese patent application No. 2021202331574 filed on Jan. 27, 2021, and entitled “DEVICE AND SYSTEM FOR TESTING FLATNESS”, the entire content of which is incorporated herein by reference. 
     TECHNICAL FIELD 
     The present disclosure relate to the technical field of flatness testing, in particular to a device and a system for testing flatness. 
     BACKGROUND 
     In related art, as flowing in a process, a glass substrate may undergo various processing processes such as film formation, etching, heating, cooling, and so on, and different degrees of stress are formed between film layers in a glass substrate. The glass substrate may deform due to excessive stress between the layers. When entering the subsequent process equipment, the glass substrate is likely to break and cause the process equipment to crash. 
     Therefore, how to test flatness of a glass substrate in order to improve the manufacturing process to reduce the flatness of the glass substrate, and avoid the problem that the glass substrate is easily broken when entering the subsequent process equipment and the process equipment is caused shut down. 
     SUMMARY 
     The present disclosure provides a device and a system. 
     In a first aspect of the embodiments of the present disclosure, a device for testing flatness is provided, including: 
     a base; 
     a testing platform assembled on the base, wherein the testing platform includes a supporting structure, the supporting structure is disposed on a side of the testing platform away from the base, and is used to support the to-be-tested board, and the supporting structure matches with a structure of the to-be-tested board; 
     a ranging sensor disposed on a side of the testing platform away from the base, wherein after the to-be-tested board is placed on the testing platform, the ranging sensor is used to test distances between a number N of to-be-tested positions on the to-be-tested board and the ranging sensor, to obtain N pieces of distance information, and the N pieces of distance information are used to determine the flatness of the to-be-tested board, where N is an integer greater than 2. 
     In an implementation, the device for testing flatness further includes a rotating shaft, a number M of said bases and M of said testing platforms, wherein the M bases are arranged around the rotating shaft, and the M bases are fixedly connected to the rotating shaft respectively, the M testing platforms are assembled on the M bases in a one-to-one correspondence, and the supporting structures of the M testing platforms are different; M is an integer greater than 1; and 
     the to-be-tested board is placed on one of the M testing platforms which is facing the ranging sensor. 
     In an implementation, the device for testing flatness further includes a driving mechanism, wherein the driving mechanism is disposed on a side of the testing platform away from the base, the ranging sensor is disposed on the driving mechanism, and the driving mechanism is used to drive the ranging sensor to move to the N to-be-tested positions respectively. 
     In an implementation, the driving mechanism includes a first linear driving mechanism, a second linear driving mechanism, and a third linear driving mechanism, wherein the first linear driving mechanism extends in a first direction, the second linear driving mechanism extends in a second direction, the third linear driving mechanism extends in a third direction, the first direction intersects the second direction, and the third direction is perpendicular to the first direction and the second direction; 
     the first linear driving mechanism is disposed on the second linear driving mechanism, and the second linear driving mechanism is used to drive the first linear driving mechanism to move along the second linear driving mechanism; 
     the third linear driving mechanism is disposed on the first linear driving mechanism, and the first linear driving mechanism is used to drive the third linear driving mechanism to move along the first linear driving mechanism; 
     the ranging sensor is disposed on the third linear driving mechanism, and the third linear driving mechanism is used to drive the ranging sensor to move along the third linear driving mechanism. 
     In an implementation, the testing platform is detachably assembled on the base, and the device for testing flatness further includes a platform storage and a platform transmission mechanism; 
     the platform storage includes a first storage space and a second storage space, the first storage space is used to store a standby testing platform, and the second storage space is an empty storage space; the supporting structure of the standby testing platform is different from the supporting structure of the testing platform assembled on the base; 
     the platform transmission mechanism is used to transport the testing platform assembled on the base to the second storage space, and transport the standby testing platform stored in the first storage space to the base. 
     In an implementation, the platform transmission mechanism includes a plurality of first rollers, a plurality of second rollers, a plurality of third rollers, a plurality of fourth rollers, a first transmission belt, a second transmission belt, a third transmission belt, a fourth transmission belt, a fifth transmission belt, a sixth transmission belt, a first motor and a second motor; 
     the base is disposed between the first transmission belt and the second transmission belt, and the platform storage is disposed between the third transmission belt and the fourth transmission belt; 
     the first motor is used to drive the first transmission belt to rotate, and the second motor is used to drive the second transmission belt to rotate; 
     the first transmission belt is used to drive the plurality of first rollers to roll, and the second transmission belt is used to drive the plurality of second rollers to roll; 
     the fifth transmission belt is sleeved on one of the first rollers and one of the third rollers, and when the plurality of first rollers roll, the fifth transmission belt drives the plurality of third rollers to roll; 
     the sixth transmission belt is sleeved on one of the second rollers and one of the fourth rollers, and when the plurality of second rollers roll, the sixth transmission belt drives the plurality of fourth rollers to roll; 
     when the platform transmission mechanism transports the testing platform assembled on the base to the second storage space, the plurality of first rollers are disposed below the testing platform assembled on the base and in contact with the testing platform assembled on the base; the plurality of second rollers are disposed below the testing platform assembled on the base and in contact with the testing platform assembled on the base; and the plurality of third rollers and the plurality of fourth rollers are disposed below the second storage space; the first motor drives the first transmission belt to rotate; and the second motor drives the second transmission belt to rotate to drive the plurality of first rollers, the plurality of second rollers, the plurality of first rollers. and the plurality of fourth rollers rotate and transport the testing platform assembled on the base to the second storage space; 
     when the platform transmission mechanism transports the standby testing platform stored in the first storage space to the base, the plurality of third rollers are disposed below the standby testing platform stored in the first storage space, and in contact with the standby testing platform stored in the first storage space; the plurality of fourth rollers are disposed below the standby testing platform stored in the first storage space, and in contact with the standby testing platform stored in the first storage space; the plurality of first rollers are aligned with the plurality of third rollers; the plurality of second rollers are aligned with the plurality of fourth rollers; the first motor drives the first transmission belt to rotate, and the second motor drive the second transmission belt to rotate to drive the plurality of first rollers, the plurality of second rollers, the plurality of third rollers, and the plurality of fourth rollers to rotate and transport the standby testing platform stored in the first storage space to the base. 
     In an implementation, the device for testing flatness further includes a first lifting apparatus disposed below the base; 
     wherein before the platform transmission mechanism transports the testing platform assembled on the base to the second storage space, the first lifting apparatus is used to drive the base to move in a third direction, so that the plurality of first rollers are disposed below the testing platform assembled on the base and in contact with the testing platform assembled on the base, and the plurality of second rollers are disposed below the testing platform assembled on the base and in contact with the testing platform assembled on the base; 
     before the platform transmission mechanism transports the standby testing platform stored in the first storage space to the base, the first lifting apparatus is used to drive the base to move in the third direction until the platform transmission mechanism transports the standby testing platform stored in the first storage space to the base; 
     when the platform transmission mechanism is not working, the first lifting apparatus is used to drive the base to move in the third direction, so that the plurality of first rollers are disposed below the testing platform assembled on the base, and out of contact with the testing platform assembled on the base, and the plurality of second rollers are disposed below the testing platform assembled on the base, and out of contact with the testing platform assembled on the base. 
     In an implementation, the device for testing flatness further includes a control apparatus, a positioning apparatus and a second lifting apparatus, wherein the control apparatus is respectively connected to the positioning apparatus and the second lifting apparatus; 
     the second lifting apparatus is used to drive the platform storage to move in a third direction; 
     the control apparatus is used to, before the control apparatus controls the platform transmission mechanism to transport the testing platform assembled on the base to the second storage space, control the second lifting apparatus to drive the platform storage to move in the third direction until the positioning apparatus detects that the testing platform assembled on the base is aligned with the second storage space; 
     the control apparatus is also used to, before the platform transmission mechanism transports the standby testing platform stored in the first storage space to the base, control the second lifting apparatus to drive the platform storage to move in the third direction until the positioning apparatus detects that a position of the standby testing platform stored in the first storage space matches a position of the base. 
     In a second aspect of the embodiments of the present disclosure, a system for testing flatness is provided, including: a material storage, a guide mechanism, and the device for testing flatness described above; 
     the material storage and the device for testing flatness are arranged around the guide mechanism; 
     the material storage is used to store a to-be-tested board, and the guide mechanism is used to take the to-be-tested board from the material storage and place them on the testing platform of the device for testing flatness. 
     In an implementation, the system for testing flatness further includes an adjustment mechanism, wherein the guide mechanism is disposed between the adjustment mechanism and the device for testing flatness; 
     the guide mechanism is also used to take a to-be-tested board from the material storage and place the to-be-tested board on the adjustment mechanism; 
     the adjustment mechanism is used to rotate the to-be-tested board so that a structure of the to-be-tested board is the same as the supporting structure of the testing platform in the same direction; 
     the guide mechanism is also used to pick up the adjusted to-be-tested board from the adjustment mechanism and place the to-be-tested board on the testing platform. 
     In an implementation, the material storage is also used to perform a corrective operation on the to-be-tested board, so that the to-be-tested board is in a first designated position; 
     the adjustment mechanism is also used to perform a corrective operation on the to-be-tested board, so that the to-be-tested board is at a second designated position. 
     It can be seen from the above, since the testing platform includes a supporting structure, and the supporting structure matches the structure of the to-be-tested board, the testing platform can simulate the supporting structure of the to-be-tested board on the process equipment and simulate the force applied on the to-be-tested board from the process equipment, and can obtain the deformation of the to-be-tested board on the process equipment. Also, since the ranging sensor is disposed on the side of the testing platform away from the base, after the to-be-tested board is placed on the testing platform, the ranging sensor can test the distances respectively from the N to-be-tested positions on the to-be-tested board to the ranging sensor, to obtain N pieces of distance information which can be used to determine the flatness of the to-be-tested board, where N is an integer greater than. 
     It is to be understood that the above general descriptions and the below detailed descriptions are merely exemplary and explanatory, and are not intended to limit the present disclosure. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate examples consistent with the present disclosure and, together with the description, serve to explain the principles of the disclosure. 
         FIG. 1  is a schematic structural diagram of a device for testing flatness according to an implementation of the present disclosure; 
         FIG. 2  is a schematic structural diagram of a testing platform according to an implementation of the present disclosure; 
         FIG. 3  is a schematic structural diagram of another testing platform according to an implementation of the present disclosure; 
         FIG. 4  is a schematic structural diagram of another testing platform according to an implementation of the present disclosure; 
         FIG. 5  is a schematic structural diagram of another testing platform according to an implementation of the present disclosure; 
         FIG. 6  is a schematic structural diagram of another device for testing flatness according to an implementation of the present disclosure; 
         FIG. 7  is a schematic structural diagram of another device for testing flatness according to an implementation of the present disclosure; 
         FIG. 8  is a schematic structural diagram of another device for testing flatness according to an implementation of the present disclosure; 
         FIG. 9  is a schematic structural diagram of another device for testing flatness according to an implementation of the present disclosure; 
         FIG. 10  is a schematic structural diagram of another device for testing flatness according to an implementation of the present disclosure; 
         FIG. 11  is a schematic structural diagram of a system for testing flatness according to an implementation of the present disclosure; 
         FIG. 12  is a schematic flowchart of an operation method of the system for testing flatness according to an implementation of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     Embodiments will be described in detail herein, with the illustrations thereof represented in the drawings. When the following descriptions involve the drawings, like numerals in different drawings refer to like or similar elements unless otherwise indicated. The implements described in the following embodiments do not represent all implements consistent with the present disclosure. Rather, they are merely examples of apparatuses and methods consistent with some aspects of the present disclosure as detailed in the appended claims. 
     An embodiment of the present disclosure provides a device for testing flatness. The device for testing flatness, as shown in  FIG. 1 , includes: a base  11 , a testing platform  12  and a ranging sensor  13 . 
     As shown in  FIG. 1 , the testing platform  12  is assembled on the base  11 , and the testing platform  12  includes a supporting structure. The supporting structure is disposed on the side of the testing platform  12  away from the base  11  for supporting a to-be-tested board; the supporting structure matches the structures of the to-be-tested board. 
     The ranging sensor  13  is disposed on the side of the testing platform  12  away from the base  11 . After a to-be-tested board is placed on the testing platform  12 , the ranging sensor  13  is used to test distances between a number N of to-be-tested positions on the to-be-tested board and the ranging sensor  13 , to obtain N pieces of distance information, and the N pieces of distance information are used to determine the flatness of the to-be-tested board, where N is an integer greater than 2. 
     In this embodiment, since the testing platform  12  includes a supporting structure, and the supporting structure matches the structure of the to-be-tested board, the testing platform  12  can simulate the supporting structure of the to-be-tested board on the process equipment and simulate the force applied on the to-be-tested board from the process equipment, and can obtain the deformation of the to-be-tested board on the process equipment. Also, since the ranging sensor  13  is disposed on the side of the testing platform  12  away from the base  11 , after the to-be-tested board is placed on the testing platform  12 , the ranging sensor  13  can test the distances respectively from the N to-be-tested positions on the to-be-tested board to the ranging sensor  13 , to obtain N pieces of distance information which can be used to determine the flatness of the to-be-tested board, where N is an integer greater than 2. Accordingly, the technical solution provided by the embodiment of the present disclosure can simulate the force applied to the to-be-tested board from the process equipment and test the flatness of the to-be-tested board. Furthermore, the technical solution provided by the embodiment of the present disclosure can test the flatness of the glass substrate, so as to improve the manufacturing process to reduce the flatness of the glass substrate, and avoid the problem that the glass substrate is easily broken when entering the subsequent process equipment and the process equipment is caused shut down. 
     The device for testing flatness provided by the embodiment of the present disclosure has been briefly introduced above, and the device for testing flatness provided by the embodiment of the present disclosure will be described in detail below. 
     An implementation of the present disclosure also provides a device for testing flatness. The device for testing flatness, as shown in  FIG. 1 , includes: a base  11 , a testing platform  12  and a ranging sensor  13 . 
     In this implementation, the base  11  can be disposed on a rack (not shown). The number of the base  11  is one. 
     In this implementation, as shown in  FIG. 1 , the testing platform  12  is assembled on the base  11 . Here, the testing platform  12  is detachably assembled on the base  11 . However, the testing platform  12  can also be fixedly assembled on the base  11 . When the testing platform  12  needs to be assembled on the base  11 , the testing platform  12  can be manually assembled on the base  11 , or the testing platform  12  can be assembled on the base  11  by an automated tool. 
     In this implementation, the device for testing flatness can further include a pneumatic gripper and a first cylinder. The pneumatic gripper is disposed on the base  11  and is used to secure the testing platform  12 . The first cylinder is used to drive the pneumatic gripper to close and release. When the pneumatic gripper is closed, the testing platform  12  is secured on the base  11 , and when the pneumatic gripper is released, the testing platform  12  can be removed. Here, the testing platform  12  can be removed manually or by an automated tool. 
     In this implementation, as shown in  FIG. 2 , the testing platform  12  includes a base plate  121 , a supporting structure  122  and an installation positioning hole  123 . The supporting structure  122  is disposed on the side of the base plate  121  away from the base  11 , that is, the supporting structure  122  is disposed on the side of the testing platform  12  away from the base  11 , and is used to support a to-be-tested board  14 . The supporting structure  122  of the testing platform  12  matches the structure of the to-be-tested board  14 . The installation positioning hole  123  is used to cooperate with a positioning pin on the to-be-tested board  14  to realize the positioning of the to-be-tested board  14 , or to realize alignment of the to-be-tested board  14  and the testing platform  12 . 
     In this implementation, the to-be-tested board  14  is a glass substrate. The glass substrate can include a glass base substrate and a driving circuit layer on the glass base substrate, but is not limited thereto. The glass substrate is a glass substrate in the process of producing the liquid crystal display base plate  121 . However, the glass substrate can also be the glass substrate in the process of producing the OLED display substrate. 
     It should be noted that the process of producing the liquid crystal display substrate can include a plurality of process steps such as a molybdenum etching process, a vapor deposition process, and a sputtering process. In different process steps, the structure of the glass substrate can be different, and the supporting structure of the process equipment to the glass substrate can be different, for example, the positions of the supporting structures are different and the configurations of the supporting structure are different. For example, the supporting structure can include a plurality of support columns, and can also include a plurality of support pads, but is not limited thereto. Therefore, the corresponding testing platform  12  can be assembled on the base  11  according to the testing requirements. Here, the supporting structure  122  of the testing platform  12  is the same as the supporting structure of the process equipment used in the specific process. In each specific process, the structure of the to-be-tested board  14  supported on the process equipment can have a specific structure. Therefore, the supporting structure  122  of the testing platform  12  matches the structure of the to-be-tested board  14 . 
     For example, in the molybdenum etching process, the supporting structure  122  of the process equipment for the glass substrate can be as shown in  FIG. 3 . Then, if the flatness of the glass substrate on the process equipment needs to be tested in the molybdenum etching process, the testing platform  12  can adopt the support structure  122  shown in  FIG. 3 . As shown in  FIG. 3 , the supporting structure  122  includes  6  support columns, the cross section of the support columns is circular, and diameters of the support columns can be different. 
     For another example, in the vapor deposition process, the supporting structure  122  of the process equipment for the glass substrate can be as shown in  FIG. 4 . Then, if the flatness of the glass substrate on the process equipment needs to be tested in the vapor deposition process, the testing platform  12  can adopt the support structure  122  shown in  FIG. 4 . As shown in  FIG. 4 , the supporting structure  122  includes  8  support columns, the cross section of the support columns is rectangular, and the size of the support columns can be the same. 
     For another example, in the sputtering process, the supporting structure  122  of the process equipment for the glass substrate can be as shown in  FIG. 5 . Then, if the flatness of the glass substrate on the process equipment needs to be tested in the sputtering process, the testing platform  12  can adopt the support structure  122  shown in  FIG. 5 . As shown in  FIG. 5 , the supporting structure  122  includes  8  support columns, the cross section of the support columns is circular, and the diameter of the support columns can be the same. 
     In this implementation, as shown in  FIG. 1 , the ranging sensor  13  is disposed on the side of the testing platform  12  away from the base  11 . When the flatness of the to-be-tested board needs to be tested, the to-be-tested board can be placed on the testing platform  12 . After the to-be-tested board is placed on the testing platform  12 , the ranging sensor  13  tests the distances between the N to-be-tested positions on the to-be-tested board and the ranging sensor  13  to obtain N pieces of distance information. The N pieces of distance information are used to determine the flatness of the to-be-tested board, and N is an integer greater than 2. For example, N is 3, 4, 5, 10, 15, 16, or 20, which is not limited thereto. 
     In this implementation, when the ranging sensor  13  tests the distance between a to-be-tested position on the to-be-tested board and the ranging sensor  13 , the ranging sensor  13  can be disposed directly above the to-be-tested position, that is, the orthographic projection of the ranging sensor  13  on the to-be-tested board coincides with the to-be-tested position. 
     In this implementation, the number of the ranging sensors  13  can be one, or two, three, or more than three. When the number of the ranging sensors  13  is less than N, the distance between the to-be-tested positions on the to-be-tested board and the ranging sensor  13  can be tested by moving the position of the ranging sensor  13 . The position of the ranging sensor  13  can be moved by an automated tool or manually. When the number of ranging sensors  13  is large, the testing efficiency can be improved. It should be noted that the automation tools herein are a collective term, rather than a term of a specific device. 
     In this implementation, since the testing platform  12  includes a supporting structure  122 , and the supporting structure  122  matches the structure of the glass substrate, the testing platform  12  can simulate the supporting structure  122  of the glass substrate on the process equipment and simulate the force applied on the glass substrate from the process equipment. Also, since the testing platform  12  is provided with a ranging sensor  13  on the side away from the base  11 , when the glass substrate is placed on the testing platform  12 , the ranging sensor  13  can test the distances respectively from the N to-be-tested positions on the to-be-tested board to the ranging sensor  13 , to obtain N pieces of distance information which can be used to determine the flatness of the to-be-tested board. Accordingly, the technical solution provided by the implementation of the present disclosure can simulate the force applied to the to-be-tested board from the process equipment and test the flatness of the to-be-tested board. Furthermore, the technical solution provided by the implementation of the present disclosure can test the flatness of the glass substrate, so as to improve the manufacturing process to reduce the flatness of the glass substrate, and avoid the problem that the glass substrate is easily broken when entering the subsequent process equipment causing the process equipment to shut down. 
     An implementation of the present disclosure also provides a device for testing flatness. The device for testing flatness, as shown in  FIG. 6 , includes: a rotating shaft  15 , a base  11 , a testing platform  12 , a ranging sensor  13  and a driving mechanism  16 . 
     As shown in  FIG. 6 , in this implementation, the device for testing flatness includes four bases  11 . The four bases  11  are arranged around a rotating shaft  15 , and the four bases  11  are fixedly connected to the rotating shaft  15  respectively, and there are four testing platforms  12  which are assembled on the four bases  11  in a one-to-one correspondence, and the supporting structures  122  of the four testing platforms  12  are different. For example, the four testing platforms  12  respectively correspond to the supporting structures of the glass substrate by different kinds of process equipment. However, in other implementations, two, three, five, six, or other numbers of testing platforms  12  can also be provided around the rotating shaft  15 . 
     As shown in  FIG. 7 , in this implementation, the to-be-tested board  14  is placed on one of the four testing platforms  12  which is facing the ranging sensor  13 . When the other three testing platforms  12  are not facing the ranging sensor  13 , the to-be-tested board  14  is not placed on the three testing platforms. By rotating the rotating shaft  15 , the testing platform  12  meeting the testing requirements can be rotated to a position facing the ranging sensor  13 . For example, the testing platform  12  facing the ranging sensor  13  can be switched every time the rotating shaft  15  rotates 90 degrees. The rotating shaft  15  can be connected to a driving motor through a coupling or a belt to obtain rotating power, but it is not limited to this. 
     In this implementation, the driving mechanism  16  is disposed on the side of the testing platform  12  away from the base  11 , the ranging sensor  13  is disposed on the driving mechanism  16 , and the driving mechanism  16  is used to drive the ranging sensor  13  to move to N to-be-tested positions respectively. It can be understood that when there is only one ranging sensor  13  on the driving mechanism  16 , the ranging sensor  13  drives the ranging sensor  13  to move to the N to-be-tested positions respectively. When there are two ranging sensors  13  connected to the driving mechanism  16 , the two ranging sensors  13  can be simultaneously driven to N/2 to-be-tested positions respectively to obtain N pieces of distance information in total, which can improve the testing efficiency. When there are more than two ranging sensors  13  connected to the driving mechanism  16 , by driving the ranging sensors  13 , the ranging sensors  13  can collect N pieces of distance information corresponding to the N to-be-tested positions. 
     In this implementation, as shown in  FIG. 8 , the driving mechanism  16  includes a first linear driving mechanism  161 , a second linear driving mechanism  162  and a third linear driving mechanism  163 . The first linear driving mechanism  161  extends in a first direction, the second linear driving mechanism  162  extends in a second direction, and the third linear driving mechanism  163  extends in a third direction, the first direction intersects the second direction, and the third direction is perpendicular to the first direction and the second direction. Here, the first direction is the Y direction, the second direction is the X direction, the third direction is the Z direction, and the first direction and the second direction are perpendicular to each other. 
     The first linear driving mechanism  161  is disposed on the second linear driving mechanism  162 , and the second linear driving mechanism  162  is used to drive the first linear driving mechanism  161  to move along the second linear driving mechanism  162 . The third linear driving mechanism  163  is disposed on the first linear driving mechanism  161 , and the first linear driving mechanism  161  is used to drive the third linear driving mechanism  163  to move along the first linear driving mechanism  161 . The ranging sensor  13  is disposed on the third linear driving mechanism  163 , and the third linear driving mechanism  163  is used to drive the ranging sensor  13  to move along the third linear driving mechanism  163 . In this way, the ranging sensor  13  can move in the first direction, the second direction, and the third direction, respectively. Before placing the to-be-tested board on the testing platform  12 , the ranging sensor  13  can be driven to move in the third direction away from the testing platform  12  to provide enough space to facilitate the placement of the to-be-tested board on the testing platform  12 . 
     An implementation of the present disclosure also provides a device for testing flatness. On the basis of the implementation shown in  FIG. 6 , in this implementation, as shown in  FIGS. 9 to 10 , the device for testing flatness further includes: a platform storage  61 , a platform transmission mechanism (not shown), a control apparatus (not shown), a positioning apparatus (not shown), a first lifting apparatus (not shown), and a second lifting apparatus (not shown). 
     In this implementation, as shown in  FIG. 9 , the platform storage  61  includes a first storage space C 1  and a second storage space C 2 . The first storage space C 1  is used to store one or more standby testing platforms  12 , and the second storage space C 2  is an empty storage space. The supporting structure  122  of the standby testing platform  12  is different from the supporting structure  122  of the testing platform  12  assembled on the base  11 , and the standby testing platform  12  is used to replace the testing platform  12  assembled on the base  11 . The empty storage space is used to store the testing platform  12  detached from the base  11 . Each of the positions of the testing platforms  12  in the platform storage  61  can be recorded in the memory of the device for testing flatness for query. 
     In this implementation, the platform transmission mechanism is used to transport the testing platform  12  assembled on the base  11  to the second storage space C 2 , and transport the standby testing platform  12  stored in the first storage space C 1  to the base  11 . 
     In this implementation, as shown in  FIG. 9 , the platform transmission mechanism includes a plurality of first rollers  62 , a plurality of second rollers  63 , a plurality of third rollers  64 , a plurality of fourth rollers  65 , a first transmission belt  66 , a second transmission belt  67 , a third transmission belt  68 , a fourth transmission belt  69 , a fifth transmission belt  610 , a sixth transmission belt  611 , a first motor  612  and a second motor  613 . 
     In this implementation, the first transmission belt  66 , the second transmission belt  67 , the third transmission belt  68 , the fourth transmission belt  69 , the fifth transmission belt  610 , and the sixth transmission belt  611  can be leather belts. 
     As shown in  FIG. 9 , the base  11  is disposed between the first transmission belt  66  and the second transmission belt  67 , and the platform storage  61  is disposed between the third transmission belt  68  and the fourth transmission belt  69 . 
     In this implementation, the first motor  612  is used to drive the first transmission belt  66  to rotate, and the second motor  613  is used to drive the second transmission belt  67  to rotate. The first motor  612  and the second motor  613  operate synchronously. For example, the first motor  612  and the second motor  613  are started at the same time and stopped at the same time, and the rotation direction of the first motor  612  is the same as the rotation direction of the second motor  613 . Here, the first transmission belt  66  is used to drive the plurality of first rollers  62  to roll, and the second transmission belt  67  is used to drive the plurality of second rollers  63  to roll. 
     As shown in  FIG. 9 , the fifth transmission belt  610  is sleeved on one of the first rollers  62  and one of the third rollers  64 . When the plurality of first rollers  62  roll, the fifth transmission belt  610  drives the plurality of third rollers  64  to roll. The distance between the first roller  62  and the third roller  64  which are sleeved by the fifth transmission belt  610  is the smallest, and the distance between the third roller  64  and the first roller  62  which are sleeved by the fifth transmission belt  610  is the smallest. 
     As shown in  FIG. 9 , the sixth transmission belt  611  is sleeved on one of the second rollers  63  and one of the fourth rollers  65 . When the plurality of second rollers  63  roll, the sixth transmission belt  611  drives the plurality of fourth rollers  65  to roll. The distance between the second roller  63  and the fourth roller  65  which are sleeved by the sixth transmission belt  611  is the smallest, and the distance between the fourth roller  65  and the second roller  63  which are sleeved by the sixth transmission belt  611  is the smallest. 
     When the platform transmission mechanism transports the testing platform  12  assembled on the base  11  to the second storage space C 2 , the platform transmission mechanism performs a closing action, and the plurality of first rollers  62  are disposed below the testing platform  12  assembled on the base  11  and in contact with the testing platform  12  assembled on the base  11 ; the plurality of second rollers  63  are disposed below the testing platform  12  assembled on the base  11 , and in contact with the testing platform  12  assembled on the base  11 ; and the plurality of third rollers  64  and the plurality of fourth rollers  65  are disposed below the second storage space C 2 . The first motor  612  drives the first transmission belt  66  to rotate, and the second motor  613  drives the second transmission belt  67  to rotate to drive the plurality of first rollers  62 , the plurality of second rollers  63 , the plurality of third rollers  64 , and the a plurality of fourth rollers  65  to rotate and to transport the testing platform  12  assembled on the base  11  to the second storage space C 2 . 
     When the platform transmission mechanism transports the standby testing platform  12  stored in the first storage space C 1  to the base  11 , the platform transmission mechanism performs a closing action, and the plurality of third rollers  64  are disposed below the standby testing platform  12  stored in the first storage space C 1 , and in contact with the standby testing platform  12  stored in the first storage space C 1 ; the plurality of fourth rollers  65  are disposed below the standby testing platform  12  stored in the first storage space C 1 , and in contact with the standby testing platform  12  stored in the first storage space C 1 ; the plurality of first rollers  62  are aligned with the plurality of third rollers  64 , the plurality of second rollers  63  are aligned with the plurality of fourth rollers  65 ; the position of the first roller  62  and the position of the second roller  63  match with the position of the base  11 , so that the standby testing platform  12  can be transported to the base  11  through the first rollers  62  and the second rollers  63 . The first motor  612  drives the first transmission belt  66  to rotate, and the second motor  613  drives the second transmission belt  67  to rotate to drive the plurality of first rollers  62 , the plurality of second rollers  63 , the plurality of third rollers  64 , and the plurality of fourth rollers  65  to rotate and to transport the standby testing platform  12  stored in the first storage space C 1  to the base  11 . 
     In this implementation, when the platform transmission mechanism transports the testing platform  12  assembled on the base  11  to the second storage space C 2  and when the platform transmission mechanism transports the standby testing platform  12  stored in the first storage space C 1  to the base  11 , the platform transmission mechanism performs the closing action. When the platform transmission mechanism is not working, the platform transmission mechanism performs an opening action, and the platform transmission mechanism moves away from the testing platform  12  and the platform storage  61 . That is, the opening action and the closing action are actions along the X direction. Here, the aforementioned closing and opening actions can be realized pneumatically. For example, the device for testing flatness includes a third cylinder, and the third cylinder provides power for realizing the aforementioned closing and opening actions. 
     In this implementation, the first lifting apparatus is disposed below the base  11 . The first lifting apparatus can include a fourth cylinder. The fourth cylinder is used to provide power for the first lifting apparatus. The first lifting apparatus is used to move the base  11  up and down along a third direction. Here, moving upward in the third direction refers to moving in the positive direction of the Z axis, and moving downward in the third direction refers to moving in the negative direction of the Z axis. 
     In this implementation, before the platform transmission mechanism transports the testing platform  12  assembled on the base  11  to the second storage space C 2 , the first lifting apparatus is used to drive the base  11  to move downward in the third direction, so that the plurality of first rollers  62  are disposed below the testing platform  12  assembled on the base  11  and in contact with the testing platform  12  assembled on the base  11 , and the plurality of second rollers  63  are disposed below the testing platform  12  assembled on the base  11  and in contact with the testing platform  12  assembled on the base  11 . 
     In this implementation, before the platform transmission mechanism transports the standby testing platform  12  stored in the first storage space C 1  to the base  11 , the first lifting apparatus is used to drive the base  11  to move downward in the third direction until the platform transmission mechanism transports the standby testing platform  12  stored in the first storage space C 1  to the base  11 . 
     When the platform transmission mechanism is not working, the first lifting apparatus is used to drive the base  11  to move upward in the third direction, so that the plurality of first rollers  62  are disposed below the testing platform  12  assembled on the base  11  and out of contact with the testing platform  12  assembled on the base  11 , and the plurality of second rollers  63  are disposed below the testing platform  12  assembled on the base  11 , and are out of contact with the testing platform  12  assembled on the base  11 , which facilitates the platform transmission mechanism to perform the opening action away from the testing platform  12  and the platform storage  61 , to avoid misalignment of the testing platform  12  on the base  11 . 
     In this implementation, the second lifting apparatus is used to drive the platform storage  61  to move in the third direction. The second lifting apparatus can include a second cylinder. The second cylinder is used to provide power for the second lifting apparatus. 
     In this implementation, the control apparatus is respectively connected to the positioning apparatus and the second lifting apparatus. Before the control apparatus controls the platform transmission mechanism to transport the testing platform  12  assembled on the base  11  to the second storage space C 2 , the control apparatus controls the second lifting apparatus to drive the platform storage  61  to move in the third direction until the positioning apparatus detects the testing platform  12  assembled on the base  11  is aligned with the second storage space C 2 . Here, the positioning apparatus includes a plurality of proximity sensors and metal pieces, the metal pieces are disposed on the platform storages  61 , the plurality of proximity sensors are disposed on the frame, and the plurality of proximity sensors correspond to a plurality of positions in a one-to-one correspondence. When the testing platform  12  assembled on the base  11  needs to be aligned with one of the second storage spaces C 2 , the corresponding proximity sensor is enabled, other proximity sensors is disabled, and the second lifting apparatus drives the platform storage  61  to move in the third direction. When the proximity sensor detects the metal piece, it is regarded as detecting that the testing platform  12  assembled on the base  11  is aligned with the second storage space C 2 . However, the implementation of the positioning apparatus is not limited to the proximity sensor and metal pieces in this implementation. 
     In this implementation, before the platform transmission mechanism transports the standby testing platform  12  stored in the first storage space C 1  to the base  11 , the control apparatus also controls the second lifting apparatus to drive the platform storage  61  to move in the third direction, until the positioning apparatus detects that the position of the standby testing platform  12  stored in the first storage space C 1  matches the position of the base  11 , that is, the standby testing platform  12  stored in the first storage space C 1  can be transported to the base  11  through the platform transmission mechanism. 
     An embodiment of the present disclosure also provides a system for testing flatness. As shown in  FIG. 11 , the system for testing flatness includes: a material storage  111 , a guide mechanism  112 , and the device for testing flatness of any one of the above embodiment. 
     As shown in  FIG. 11 , the material storage  111  and the device for testing flatness are arranged around the guide mechanism  112 . The guide mechanism  112  can be, for example, a robot arm. 
     In this embodiment, the material storage  111  is used to store a to-be-tested board, for example, to store a glass substrate. 
     In this embodiment, the guide mechanism  112  is used to take a to-be-tested board from the material storage  111  and place it on the testing platform  12  of the device for testing flatness, and is also used to remove the to-be-tested board away from the testing platform  12  after the testing is completed and place it in the material storage  111 . When the guide mechanism  112  is not working, the guide mechanism  112  returns to an idle station and waits for the next instruction to be executed. 
     In this embodiment, the material storage  111  is also used to perform corrective operations on the to-be-tested board, so that the to-be-tested board is placed at a first designated position. In this way, when the guide mechanism  112  takes the to-be-tested board from the material storage  111 , the relative positions of the guide mechanism  112  and the to-be-tested board is known, which is convenient for controlling the position of the to-be-tested board on the testing platform  12 . 
     In this embodiment, the system for testing flatness further includes a data processing unit for processing the obtained N pieces of distance information to determine the flatness of the to-be-tested board. 
     The embodiment of the present disclosure also provides a system for testing flatness. As shown in  FIG. 11 , the system for testing flatness includes: a material storage  111 , a guide mechanism  112 , an adjustment mechanism  113 , and the device for testing flatness of any of the above embodiments. 
     In this embodiment, the material storage  111 , the adjustment mechanism  113  and the device for testing flatness are arranged around the guide mechanism  112 . 
     In this embodiment, the guide mechanism  112  is used to take out the to-be-tested board from the material storage  111  and place it on the adjustment mechanism  113 . The adjustment mechanism  113  is used to rotate the to-be-tested board so that the structure of the to-be-tested board is the same as the supporting structure  122  of the testing platform  12  in the same direction. In this way, after the guide mechanism  112  picks up the adjusted to-be-tested board from the adjusting mechanism  113 , the guide mechanism  112  does not need to perform a rotation operation, and only needs to perform a translation operation to place the to-be-tested board on the testing platform  12 , which is convenient for controlling the position of the to-be-tested board on the testing platform  12 . 
     In this embodiment, the adjustment mechanism  113  is also used to perform a corrective operation on the to-be-tested board, so that the to-be-tested board is in a second designated position, so that when the guide mechanism  112  takes the to-be-tested board from the adjustment mechanism  113  At this time, the relative position of the guide mechanism  112  and the to-be-tested board is known, which is convenient for controlling the position of the to-be-tested board on the testing platform  12 . 
     In this embodiment, the guide mechanism  112  is used to pick up the adjusted to-be-tested board from the adjustment mechanism  113  and place it on the testing platform  12 . 
     In this embodiment, the working process of the system for testing flatness can be as shown in  FIG. 12 , including the following steps  1201  to  1210 : 
     In step  1201 , it is detected whether there is a to-be-tested board in the material storage  111 . If so, go to step  1202 , if not, go to step  1209 . 
     In step  1202 , it is detected whether there is an abnormality in the number and position of the to-be-tested board. If not, go to step  1203 , and if so, go to step  1209 . 
     In step  1203 , it is detected whether the state of the guide mechanism  112  is abnormal. If not, go to step  1204 , and if so, go to step  1209 . 
     In step  1204 , the to-be-tested board is picked up from the testing material storage  111  and placed on the adjustment mechanism  113 . 
     In step  1205 , the adjustment mechanism  113  corrects and rotates the to-be-tested board. 
     In step  1206 , the to-be-tested board is picked up from the adjustment mechanism  113  and placed on the testing platform  12  for testing. In this step, the purpose of testing is to obtain N pieces of distance information to determine the flatness of the to-be-tested board. 
     In step  1207 , it is determined whether the testing is over. If so, go to step  1208 , if not, go to step  1210 . 
     In step  1208 , the to-be-tested board is removed from the testing platform  12  and placed in the material storage  111 . 
     In step  1209 , an alarm is issued and the process is interrupted. 
     In step  1210 , wait for testing. 
     Here, the work of the system for testing flatness has been described above, and will not be repeated here. 
     In this embodiment, it is possible to simulate the force applied to the to-be-tested board from the process equipment and test the flatness of the to-be-tested board. Furthermore, the technical solution provided by the embodiments of the present disclosure can test the flatness of the glass substrate, so as to improve the manufacturing process to reduce the flatness of the glass substrate, and avoid the problem that the glass substrate is easily broken when entering the subsequent process equipment and the process equipment is caused shut down. 
     Here, the processes used in the above embodiments can include, for example, film forming processes such as deposition and sputtering, and patterning processes such as etching. 
     It should be pointed out that in the drawings, the sizes of layers and regions can be exaggerated for clarity of illustration. It will also be understood that when an element or layer is referred to as being “on” another element or layer, it can be directly on the other element or intervening layers can be present. In addition, it will be understood that when an element or layer is referred to as being “under” another element or layer, it can be directly under the other element, or there can be more than one intervening layer or element. In addition, it can also be understood that when a layer or element is referred to as being “between” two layers or two elements, it can be the only layer between the two layers or two elements, or more than one intervening layer or element can also be present. Similar reference numerals indicate similar elements throughout. 
     In the present disclosure, the terms “first” and “second” are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance. The term “plurality” refers to two or more, unless specifically defined otherwise. 
     Other implementations of the present disclosure will be apparent to those skilled in the art from consideration of the specification and practice of the present disclosure herein. The present disclosure is intended to cover any variations, uses, modification or adaptations of the present disclosure that follow the general principles thereof and include common knowledge or conventional technical means in the related art that are not disclosed in the present disclosure. The specification and examples are considered as exemplary only, with a true scope and spirit of the present disclosure being indicated by the following claims. 
     It is to be understood that the present disclosure is not limited to the precise structure described above and shown in the accompanying drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present disclosure is limited only by the appended claims.