Patent Publication Number: US-2019189831-A1

Title: Processing method for removing film and apparatus for removing film

Description:
The present application claims priority to the China Patent Application No. 201711375583.6, entitled “PROCESSING METHOD FOR REMOVING FILM AND APPARATUS FOR REMOVING FILM” filed on Dec. 19, 2017 and No. 201711377087.4, entitled “PROCESSING METHOD FOR REMOVING FILM AND APPARATUS FOR REMOVING FILM” filed on Dec. 19, 2017, the entire contents of which are incorporated herein by reference. 
     FIELD OF THE INVENTION 
     The present disclosure relates to a photovoltaic technology, and more particularly to a processing method for removing film and apparatus for removing film. 
     BACKGROUND 
     A film removal photovoltaic module is widely used because they can generate electricity and light, for example, it can be integrated with buildings, automobiles, etc., namely, a Building Integrated Photovoltaic (BIPV), and it can be attached to a building, namely, a Building Attached Photovoltaic (BAPV), and so on. 
     At present, the production of a film removal of a thin film solar cell is mostly achieved by laser engraving. In the related art, the laser film removal is generally performed by an engraved line method in which a motor drives a laser head, or an engraving line mode in which a cell sheet reciprocates in a case where the laser beam is not moved. 
     SUMMARY 
     In one aspect, some embodiments of the present disclosure provide an apparatus for removing film comprising an optical component and a processor, wherein the optical component includes: a laser generator configured to generate a laser beam; a first scanning galvanometer configured to reflect the laser beam; and a second scanning galvanometer configured to reflect the laser beam reflected by the first scanning galvanometer; wherein the processor is configured to control the laser generator to generate the laser beam, and to control the first scanning galvanometer and the second scanning galvanometer to deflect, thereby performing a film removal process on a target object. 
     In another aspect, some embodiments of the present disclosure provide a processing method for removing film applying the apparatus for removing film of the first aspect. the method comprising: controlling the laser generator to generate a laser beam, and controlling the first scanning galvanometer and the second scanning galvanometer to deflect, so that the laser beam is sequentially reflected by the first scanning galvanometer and the second scanning galvanometer to reach the target object, thereby performing the film removal process on the target object. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The drawings described herein are intended to provide a further understanding of the present disclosure, are intended to be a part of the present disclosure, and are used to explain the technical solutions of the present disclosure with embodiments of the present disclosure, which do not constitute a limitation of the technical solutions of the present disclosure. In the drawing: 
         FIG. 1  is a schematic view showing a structure of a solar cell which is applied in some embodiments of the present disclosure. 
         FIG. 2  is a schematic view showing an apparatus for removing film and method for removing film in the related art. 
         FIG. 3( a )  is a schematic view showing a composition of the apparatus for removing film according to some embodiments of the present disclosure. 
         FIG. 3( b )  is a schematic view showing a structure of an apparatus for removing film applied in a certain circumstance according to some embodiments of the present disclosure. 
         FIG. 4( a )  is a schematic view showing a condition of an engraved line distortion on a solar cell. 
         FIG. 4( b )  is a schematic view showing another condition of an is engraved line distortion on a solar cell. 
         FIG. 4( c )  is a schematic view showing a multiple-face splicing solution during the film removal process according to some embodiments of the present disclosure. 
         FIG. 5( a )  is a schematic view showing a solution for a movement of a target object during a film removal process according to some embodiments of the present disclosure. 
         FIG. 5( b )  is a schematic view showing a scanning path of the laser beam in the solution as shown in  FIG. 5( a ) . 
         FIG. 6  is a flowchart of a processing method for removing film according to some embodiments of the present disclosure. 
         FIG. 7  is a flowchart of another processing method for removing film according to some embodiments of the present disclosure. 
         FIG. 8  is a flow chart of another processing method for removing film according to some embodiments of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     Embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings. It should be noted that, in the case of no conflict, the features in the embodiments and the embodiments in the present disclosure may be arbitrarily combined with each other. 
     The steps illustrated in the flowcharts in the drawings may be performed in a computer system including a set of computer-executable instructions. Also, although logical sequences are shown in the flowcharts, in some cases the steps shown or described may be performed in a different order. 
     An apparatus for removing film and method for removing film according to some embodiments of the present disclosure can perform a film removal process on a target object. For example, a solar cell as shown in  FIG. 1  is subjected to a film removal process. The solar cell includes a back electrode layer  1 , a photovoltaic film layer  2 , a front electrode layer  3 , and a transparent substrate  4  in order. A general film removal process uses a laser to selectively etch the back electrode layer  1  and the photovoltaic film layer  2 , or the back electrode layer  1 , the photovoltaic film layer  2 , and the front electrode layer  3 . 
     A processing method for removing film of a solar cell in the related art is shown in  FIG. 2 . The solar cell  200  has cell structure engraved lines  221  parallel to an X-axis. This cell structure engraved lines  221  are inherent engraved lines on the solar cell  200 , so a laser generator  210  does not need to perform a film removal process to obtain these cell structure engraved lines  221 . Film removal engraved lines  220  parallel to a Y-axis on the solar cell  200  are required to be obtained through the film removal process performed by the laser generator  210 . The specific processing method for removing film in the related art is as follows. 
     The laser generator  210  is fixed at a position where a laser beam emitted by the laser generator  210  is parallel to a Z-axis. That is, the laser generator  210  emits light in a fixed direction. The laser beam  211  generated by the laser generator  210  is focused by a focusing mirror  212 . The solar cell  200  is grasped on a platform which is parallel to the XOY plane. This platform may drive the solar cell  200  in a direction parallel to the Y-axis by mechanical movement along the Y-axis to produce a film removal engraved line  220  parallel to the Y-axis. After producing a complete film removal engraved line  220  parallel to the Y-axis, if it is desired to generate another film removal engraved line  220  parallel to the Y-axis, it is necessary to drive the solar cell  200  to step through the mechanical movement of the platform along the X-axis, further, through the mechanical movement of the platform along the Y-axis, the solar cell  200  is driven to move in a direction parallel to the Y-axis to produce another film removal engraved line  220  parallel to the Y-axis. 
     The processing method for removing film in the related art is limited by the mechanical movement capability. an engraving velocity may only reach 1000˜2000 mm/s, and a spot diameter or a spot width is generally limited to about 50 μm˜100 μm, so a film removal rate is lower. Further, in the laser film removal process in the related art, in order to increase the film removal rate, a plurality of laser heads are used for simultaneous processing. Due to the difference in performance of each laser, it is easy to generate a chromatic aberration or result in inconsistent spot diameters (or widths) in different processing areas. Inconsistent spot diameters (or widths) will result in inconsistent widths of the engraved lines, thereby affecting a subsequent processing, or affecting a film quality. 
     In the following, an apparatus for removing film and method for removing film according to some embodiments of the present disclosure will be mainly described by taking a film removal process of a solar cell as an example, that is, taking a target object as a solar cell chip as an example. It can be understood that the apparatus for removing film and method for removing film are applicable to various target objects that require film removal and marking. 
     Referring to  FIG. 3( a ) , some embodiments of the present disclosure provide an apparatus for removing film including an optical component  31 , a memory  10 , and a processor  20 . 
     Referring to  FIG. 3( b ) , the optical component  31  includes: 
     a laser generator  310  configured to generate a laser beam; 
     a first scanning galvanometer  312   a  configured to reflect a laser beam; 
     a second scanning galvanometer  312   b  configured to reflect the laser beam reflected by the first scanning galvanometer  312   a.    
     That is, the optical assembly  31  includes a scanning galvanometer system including the first scanning galvanometer  312   a  and the second scanning galvanometer  312   b . A scan rate of this scanning galvanometer system may be set as 0˜20000 mm/s. 
     The processor  20  is configured to control the laser generator  310  to generate a laser beam, and to control the first scanning galvanometer  312   a  and the second scanning galvanometer  312   b  to deflect, thereby performing a film removal process on the target object  300 ′. 
     The apparatus for removing film according to some embodiments of the present disclosure controls the laser beam irradiated on the target object  300 ′ by the deflection control of the first scanning galvanometer  312   a  and the second scanning galvanometer  312   b , thereby performing the film removal process on the target object  300 ′. Compared with the related art limited by the mechanical movement capability, the apparatus for removing film according to some embodiments of the present disclosure adopt a scanning galvanometer system having the first scanning galvanometer  312   a  and the second scanning galvanometer  312   b , and can improve the engraving velocity and reduce the spot diameter, thereby greatly increasing the film removal rate of this apparatus and increasing a disposable processing area. Further, by using a single laser generator  310  in the apparatus for removing film, the problem of chromatic aberration can be improved. 
     For example, in some embodiments, when the apparatus for removing film is in use, the first scanning galvanometer  312   a  and the second scanning galvanometer  312   b  have a scan range of 0×0 mm to 1500×1500 mm, an engraved line velocity of 15000 mm/s, and a spot width (or diameter) of 1 mm. In this case, the film removal rate can reach 15000 mm 2 /s. However, in the related art, the apparatus for removing film is limited by the mechanical movement capability, the spot diameter usually does not exceed 100 μm, and the engraved line velocity does not exceed 1500 mm/s, so the film removal rate generally does not exceed 150 mm 2 /s. The velocity of the apparatus for removing film according to some embodiments of the present disclosure is 100 times faster than that of the apparatus for removing film of the related art. 
     In some embodiments of the present disclosure, the optical assembly  31  further includes a focusing mirror  313 . The focusing mirror  313  is configured to focus the laser beam reflected by the second scanning galvanometer  312   b  to the target object  300 ′ or to focus the laser beam generated by the laser generator  310  to the first scanning galvanometer  312   a . The focus mirror may be used to adjust the diameter of the laser beam; and a laser beam unit energy can be increased to improve a film removal efficiency. 
     In some embodiments of the present disclosure, a focal length of the focusing mirror  313  is larger than or equal to a preset focal length. For example, the focusing mirror  313  is a focusing mirror of a type F825. A diameter of a laser beam focused at a focal length of the focus mirror of this model is larger than or equal to a preset diameter. 
     In some embodiments of the present disclosure, a beam diameter of the laser beam generated by the laser generator  310  is controlled such that the diameter of the laser beam irradiated on the target object is larger than or equal to a preset diameter. In some embodiments of the present disclosure, the diameter of the laser beam is controlled by the processor  20  or the focusing mirror  313 . 
     In the apparatus for removing film, by making the diameter of the laser beam irradiated on the target object larger than or equal to a preset diameter, the number of times of film removal required to form an engraving line may be reduced when the apparatus for removing film is applied. That is, the film removal rate can be increased. 
     In some embodiments of the present disclosure, a power of the laser generator  310  is larger than or equal to a preset power. For example, the power of the laser generator  310  is several tens of W to several hundred W. For example, a green laser generator having a power of 100 W and a wavelength of 532 nm is used. 
     The film removal process is performed by using an apparatus for removing film with a laser generator having a larger power, and a possibility of removing the film by using a large spot is increased, which can further improve the film removal rate. 
     In some embodiments of the present disclosure, the apparatus for removing film further includes a memory  10  configured to store a film removal instruction of controlling the laser generator  310  to generate the laser beam and of controlling a occurrence a deflection of the first scanning galvanometer  312   a  and the second scanning galvanometer  312   b  to perform the film removal process on the target object  300 ′. 
     The processor  20  is configured to perform the film removal instruction stored in the memory  10 . 
     In some embodiments of the present disclosure, before controlling the deflection of the first scanning galvanometer  312   a  and the second scanning galvanometer  312   b , the processor  20  is further configured to control the target object  300 ′ or the optical assembly  31  to move to a specified position. 
     Taking the target object  300 ′ as the solar cell  300  as an example, moving the solar cell  300  or the optical component  31  to the specified position means moving the solar cell  300  or the optical component  31  to a position where the solar cell  300  and the optical component  31  satisfy a relative positional relationship. In this position, the film removal process for at least a portion of the solar cell  300  may be completed when the first scanning galvanometer  312   a  and the second scanning galvanometer  312   b  deflect. 
     In some embodiments of the present disclosure, when the target object is subjected to the film removal process, the film removal process may be performed according to a preset pattern of the film removal. The pattern of the film removal may be any pattern, for example, the pattern of the film removal may be a spot, an engraving line or other patterns, which is not limited in the present disclosure. 
     Hereinafter, a description will be given by taking the preset pattern of the film removal as the engraved line. 
     For example, in  FIG. 3( b ) , in some practical applications where it is necessary to form an engraving line  320  parallel to the Y-axis, the memory  10  may store a film removal instruction which is performed by the processor  20 , thereby completing the following configurations and operations. First, the first scanning galvanometer  312   a  and the second scanning galvanometer  312   b  are adjusted to a return-to-zero position, for example, a position where no deflection occurs. Then, the solar cell  300  or the optical component  31  is moved to a specified position so that the laser beam generated after the laser generator  310  is turned on may be focused to an upper end of a first film removal engraving line which is to be formed. Then, the laser generator  310  is controlled to turn on, the first scanning galvanometer  312   a  is controlled to remain stationary, and the second scanning galvanometer  312   b  is controlled to deflect, so that the laser beam is gradually scanned from an upper end to a lower end of the first film removal engraving line to be formed, thereby forming the first film removal engraving line. Thereafter, the laser generator  310  is controlled to turn off, the second scanning galvanometer  312   b  is controlled to remain stationary, and the first scanning galvanometer  312   a  is controlled to deflect, so that the laser beam generated after the laser generator  310  is turned on may be focused to a lower end of the second film removal engraving line to be formed. Then, the laser generator  310  is controlled to turn on, the first scanning galvanometer  312   a  is controlled to remain stationary, and the second scanning galvanometer  312   b  is controlled to deflect, so that the laser beam gradually moves from the lower end to an upper end of the second film removal engraving line to be formed, thereby forming the second film removal engraving line . . . , and so on, a plurality of film removal engraving lines  320  are formed. 
     In the case where the deflection angle of the first scanning galvanometer  312   a  is large, an incident point of the laser beam on the second scanning galvanometer  312   b  may deviate from a central area of the second scanning galvanometer  312   b , thereby distorting the film removal pattern. For example, the engraved line engraved on the solar cell is distorted. As shown in FIG.  4 ( a ), in the case of engraving a line parallel to the Y-axis, two lines on an edge are not straight due to a deviation of the above incident point, thereby forming a “pincushion” distortion, and as shown in  FIG. 4( b ) , in the case of engraving a line parallel to the x-axis, two lines on an edge are not straight due to the deviation of the above incident point, thereby forming a “barrel” distortion. In this way, the engraving lines are made non-parallel, thereby reducing the quality of the solar cell  300 . 
     In order to improve the quality of the solar cell  300 , in some embodiments of the present disclosure, the processor  20  is configured to control a deflection angle of the first scanning galvanometer  312   a  to be always less than or equal to a preset angle such that a distance between an incident point of the laser beam on the first scanning galvanometer  312   a  and a geometric center point of the first scanning galvanometer  312   a  is less than or equal to a first preset distance, and a distance between an incident point of the laser beam on the second scanning galvanometer  312   b  and a geometric center point of the second scanning galvanometer  312   b  is less than or equal to a second preset distance. 
     In this case, the galvanometer system has a scan range no larger than its web range. The web range refers to a maximum range that can be scanned when a pattern is formed by the deflection of the first scanning galvanometer  312   a  and the second scanning galvanometer  312   b  and the pattern is not distorted in the case where the galvanometer system does not move. 
     In the case where a film removal range of the target object  300 ′ is larger than the web range of the galvanometer system, in some embodiments of the present disclosure, the memory  10  stores a film removal instruction of splicing multiple-faces and the film removal instruction is performed by the processor  20 . The target object  300 ′ is divided into a plurality of preset areas, each of which is smaller than or equal to the scanning range of the first scanning galvanometer  312   a  and the second scanning galvanometer  312   b . The processor  20  is configured to perform the film removal process on each of the preset areas, that is, to perform the film removal process on the first preset area, after the completion thereof, to perform the film removal process on the second preset area, after the completion thereof, to perform the film removal process on the third preset areas, . . . , and so on, until the film removal process on all the preset areas is completed. 
     The following is an example of a multiple faces splicing being in the X direction, and the target object  300 ′ being the solar cell  300 . The solar cell  300  is first divided into a plurality of preset areas, and a side length of each of the preset areas in the X direction is less than or equal to the scanning range of the first scanning galvanometer  312   a . Then, each of the preset areas is subjected to a film removal process, that is, the first preset area is subjected to the film removal process; after the completion thereof, the second preset area is subjected to the film removal process; after the completion thereof, the third preset area is subjected to the film removal process, . . . , and so on, until the film removal process on all preset areas is completed. 
     As shown in  FIG. 4( c ) , in some embodiments of the present disclosure, it is necessary to engrave  30  film removal engraving lines  320  parallel to the Y-axis on the solar cell  300 . 
     The memory  10  may store a film removal instruction which is performed by the processor  20 , thereby completing the following configurations and operations. An area where a film is to be removed of the solar cell is divided into three preset areas along the X direction, which are a preset area  420   a , a preset area  420   b , and a preset area  420   c , respectively. Ten engraved lines  320  parallel to the Y-axis will be engraved in the preset area  420   a , the preset area  420   b , and the preset area  420   c , respectively. First, the first scanning galvanometer  312   a  and the second scanning galvanometer  312   b  are adjusted to the return-to-zero position. Then, the solar cell  300  or the optical component  31  is moved to a specified position, so that the laser beam generated after the laser generator  310  is turned on may be focused to an upper end of a first film removal engraved line to be formed in the preset area  420   a . Then, the laser generator  310  is controlled to turn on to generate the laser beam, the first scanning galvanometer  312   a  is controlled to remain stationary, and the second scanning galvanometer  312   b  is controlled to deflect, so that the laser beam gradually moves from the upper end to the lower end of the first film removal engraved line to be formed, thereby forming the first film removal engraved line. Thereafter, the laser generator  310  is controlled to turn off, the second scanning galvanometer  312   b  is controlled to remain stationary, and the first scanning galvanometer  312   a  is controlled to deflect, so that the laser beam may be focused to a lower end of the second film removal engraved line to be formed after the laser generator  310  is turned on. Then, the laser generator  310  is controlled to turn on, the first scanning galvanometer  312   a  is controlled to remain stationary, and the second scanning galvanometer  312   b  is controlled to deflect, so that the laser beam gradually moves from the lower end to the upper end of the second film removal engraved line to be formed, thereby forming the second film removal engraved line . . . , and so on,  10  film removal engraved lines  320  in the preset area  420   a  are formed. 
     Then, the solar cell  300  or the optical component  31  is moved to a next specified position, and 10 film removal engraved lines are formed in the preset area  420   b  in the above-described manner 10 film removal engraved lines are formed in the preset area  420   c  in the same step. 
     Through the multiple-face splicing method described above, the apparatus for removing film may complete the film removal process of the entire solar cell  300  in the case where the deflection angle of the first scanning galvanometer  312   a  is controlled to be less than or equal to the preset angle, thereby improving the quality of the film removal process. 
     In addition to the multiple-face splicing method described above, further solutions are provided in some embodiments such that the deflection angle of the first scanning galvanometer  312   a  is always less than or equal to the preset angle during the film removal process. In some embodiments of the present disclosure, as shown in  FIG. 3( a ) , the apparatus for removing film further includes a movable platform  32 . 
     The movable platform  32  is configured to carry the target object  300 ′ to drive the target object  300 ′ to move. 
     In some embodiments of the present disclosure, the memory  10  is configured to store a movement instruction of controlling a movement of the movable platform  32 ; and the processor  20  is further configured to perform the movement instruction to move the movable platform  32 . 
     Applying the apparatus for removing film according to the above embodiments, it is possible to drive the target object to move by controlling the movable platform  32  during the film removal process. Thus, even in the case where a multiple-face splicing is not employed, it is ensured that the deflection angle of the first scanning galvanometer  312   a  is always less than or equal to the preset angle. Also, the quality of the film is improved. Referring to  FIG. 3( b ) ,  FIG. 5( a )  and  FIG. 5( b ) , in some practical embodiments, in order to obtain a film removal engraved line  320  parallel to the Y-axis, the memory  10  may store a film removal instruction and a movement instruction which are performed by the processor  20 , thereby completing the following configuration and operations. Controlling the laser generator  310  to turn on, and controlling the first scanning galvanometer  312   a  and the second scanning galvanometer  312   b  to deflect such that the laser beam irradiating the solar cell  300  is in a first path inclined to the X-axis with respect to the XOY plane to scan. At the same time, the movable platform  32  is controlled to drive the solar cell  300  to move at a constant velocity along the −X axis as shown in  FIG. 5( a ) . The scanning velocity v 1  of the laser beam with respect to the XOY plane may be regarded as a combined velocity of a velocity v −x  along the −X axis and a velocity v −y  along the −Y axis. A velocity that the moving platform  32  drives the solar cell  300  along the −X axis is v 3 , and satisfies v −x =v 3 . That is, with respect to the solar cell  300 , the velocity at which the laser beam is engraved in the direction of the −X axis is 0, and the velocity at which the laser beam is engraved in the −Y axis direction is v −y . Thus, an engraved line  320  parallel to the Y-axis is obtained on the solar cell  300 . 
     It is known that the first path described above is a scanning path of the laser beam with respect to the XOY plane. The angle α between the first path and the X-axis satisfies sin α=L/L 1 , where L is a length of the engraved line on the solar cell and L 1  is a length of the first path. 
     To engrave the next engraved line, the laser generator  310  is controlled to be turned off first. During the turnoff of the laser generator  310 , the movable platform  32  is controlled to drive the solar cell  300  to continue to move at a constant velocity along the −X axis. A duration during which the laser generator  310  is turned off is W/v 3  (W is a distance between two adjacent engraved lines). Then, the laser generator  310  is controlled to turn on, and the first scanning galvanometer  312   a  and the second scanning galvanometer  312   b  are controlled to deflect such that the laser beam irradiating the solar cell  300  is in a second path inclined to the −X axis in relative to the XOY plane to scan. At this time, a scanning velocity v 2  of the laser beam with respect to the XOY plane may be regarded as the combined velocity of the velocity v −x  along the −X axis and the velocity v y  along the Y-axis (v y  and v −y  have the same magnitude and opposite direction) and satisfies v −x =v 3 . That is, with respect to the solar cell  300 , the velocity at which the laser beam is engraved in the direction of the −X axis is 0, and the velocity at which the laser beam is engraved in the Y-axis direction is v y . Thus, another engraved line  320  parallel to the Y-axis is obtained on the solar cell  300 . Further, as shown in  FIG. 5( b ) , an angle between the second path and the −X axis is equal to the angle between the first path and the X-axis, and is also α. 
     Next, the laser generator  310  is controlled to turn off, and during the turn off of the laser generator  310 , the movable platform  32  is controlled to drive the solar cell  300  to continue to move at a constant velocity along the −X axis. A duration which the laser generator  310  is turned off is W/v 3 . The process of engraving the two engraving lines is continued to complete the film removal process of the solar cell  300 . 
     Further, in the above process, during the turn off of the laser generator  310 , the processor  20  controls the first scanning galvanometer to return to zero, so as to ensure that the deflection angle of the first scanning galvanometer is always less than or equal to the preset angle during the film removal process. 
     It should be noted that, in the case where a power of the laser generator  310  is less than a preset power, or a diameter of the laser beam irradiated on the solar cell  300  is smaller than a preset diameter, optionally, one engraved line is engraved more than once. 
     In the case of engraving twice, after the scanning of the first path is completed, the control laser generator  310  is not turned off, the scanning direction of the second scanning galvanometer  312   b  is directly adjusted, and the first scanning galvanometer  312   a  and the second scanning galvanometer  312  are controlled to deflect to perform a second path, thereby forming two sub-engraved lines completely coincided or partially coincided in the width direction as one engraving line. Then, the laser generator  310  is controlled to turn off, and after the solar cell  300  is moved at a constant velocity along the −X axis for a period of W/v 3 , the process of forming the two sub-engraved lines completely coincided or partially coincided in the width direction is continued to form another engraved line. 
     With a similar configuration and operation, one engraved line may be formed by engraving three, four, or even more times. 
     Some embodiments of the present disclosure provide an apparatus for removing film capable of controlling the first scanning galvanometer and the second scanning galvanometer to deflect in use, controlling a movement of the target object to perform scanning film removal process on the target object, and further ensuring that the deflection angle of the first scanning galvanometer  312   a  during the film removal process be always less than or equal to the preset angle. Thus, the disposable processing area can be increased, and the film removal rate and the film removal quality can be improved. Moreover, the use of a single laser generator can increase the film removal rate and improve the chromatic aberration. 
     Referring to  FIG. 6 , some embodiments of the present disclosure provide a processing method for removing film using the apparatus for removing film as described in the above embodiments. The processing method for removing film includes the following step  650  (S 650 ). 
     S 650 , controlling the laser generator  310  to generate a laser beam, and controlling the first scanning galvanometer  312   a  and the second scanning galvanometer  312   b  to deflect, so that the laser beam is sequentially reflected by the first scanning galvanometer  312   a  and the second scanning galvanometer  312   b  to reach the target object, thereby performing the film removal process on the target object. 
     For example, in some embodiments, the first scanning galvanometer  312   a  and the second scanning galvanometer  312   b  have a scan range of 0×0 mm to 1500×1500 mm, an engraving velocity of 15000 mm/s, and a spot width (or diameter) of 1 mm. In this case, a film removal rate can reach 15000 mm 2 /s. In a processing method for removing film of the related art, when a spot diameter is 100 μm and an engraving velocity is 1500 mm/s, a film removal rate is 150 mm 2 /s. Therefore, the processing method for removing film of some embodiments of the present disclosure is more than 100 times faster than the processing method for removing film in the related art. 
     In some embodiments of the present disclosure, a scanning galvanometer system having the first scanning galvanometer  312   a  and the second scanning galvanometer  312   b  is used in the processing method for removing film, which can greatly increase the film removal rate, thereby increasing a disposable processing area. Moreover, the use of a single laser generator  310  can increase the film removal rate and improve the problem of chromatic aberration. 
     In some embodiments of the present disclosure, the target object is a solar cell  300 . 
     In some embodiments of the present disclosure, S 640  is also included before S 650 . 
     S 640 , moving the target object, or an optical component  31  including the first scanning galvanometer  312   a  and the second scanning galvanometer  312   b  to a specified position. 
     It can be understood that when the target object (for example, the solar cell  300 ) is subjected to the film removal process, the pattern of the film removal may be any pattern. For example, the pattern of the film removal may be a spot, or an engraving line, or other patterns, which is not limited in the embodiment of the present disclosure. 
     In some of the following embodiments, the engraved line will be mainly described as an example. 
     In some embodiments, as shown in  FIG. 3( b ) , a film removal engraved line  320  parallel to the Y-axis needs to be formed on the solar cell  300 . At this time, the processing method for removing film includes the following steps  701 - 707  (S 701 -S 707 ). 
     S 701 , adjusting the first scanning galvanometer  312   a  and the second scanning galvanometer  312   b  to a return-to-zero position. 
     S 702 , moving the solar cell  300  or the optical component  31  to a specified position, so that the laser beam generated after the laser generator  310  is turned on may be focused to an upper end of the first film removal engraved line to be formed. 
     S 703 , controlling the laser generator  310  to turn on, controlling the first scanning galvanometer  312   a  to remain stationary, and controlling the second scanning galvanometer  312   b  to deflect, so that the laser beam is gradually scanned from the upper end to a lower end of a first film removal engraved line to be formed, thereby forming the first film removal engraved line. 
     S 704 , controlling the laser generator  310  to turn off, controlling the second scanning galvanometer  312   b  to remain stationary, and controlling the first scanning galvanometer  312   a  to deflect, so that the laser beam generated after the laser generator  310  is turned on may be focused to a lower end of a second film removal engraved line to be formed. 
     S 705 , controlling the laser generator  310  to turn on, controlling the first scanning galvanometer  312   a  to remain stationary, and controlling the second scanning galvanometer  312   b  to deflect, so that the laser beam is gradually moved from the lower end to an upper end of the second film removal engraved line to be formed, thereby forming the second film removal engraved line  320 . 
     S 706 , controlling the laser generator  310  to turn off, controlling the second scanning galvanometer  312   b  to remain stationary, and controlling the first scanning galvanometer  312   a  to deflect, so that the laser beam generated after the laser generator  310  is turned on may be focused to an upper end of a third film removal engraved line to be formed. 
     S 707 , continuing to perform the above S 703 -S 706  to form a plurality of film removal engraved lines  320 . After forming a preset number of film removal engraved lines  320 , the step is stopped, for example, stopped after S 703  or S 705  is performed. 
     The above-described “first”, “second”, and “third” are merely intended to distinguish the various steps and are not intended to be limiting. For example, when S 703  is subsequently performed after S 706 , “the third film removal engraved line to be formed” in S 706  is the “the first film removal engraved line to be formed” in S 703  which is subsequently performed. 
     As discussed above, in some embodiments in which the film removal range of the target object exceeds the web range of the galvanometer system, when the deflection angle of the first scanning galvanometer  312   a  in the optical assembly  31  is large, the pattern of film removal is caused to be distorted, which reduces the quality of the film removal. For this problem, in some embodiments, the processing method for removing film further includes: controlling the deflection angle of the first scanning galvanometer  312   a  to be always less than or equal to the preset angle. 
     As shown in  FIG. 7 , in some embodiments of the present disclosure, in order that the film removal process of the entire target object is completed in the case where the deflection angle of the first scanning galvanometer  312  is controlled to be less than or equal to the preset angle, the method also includes step  630  (S 630 ). 
     S 630 , dividing the target object into one or more preset areas. 
     Each of the preset areas is less than or equal to the web range of the first scanning galvanometer  312   a  and the second scanning galvanometer  312   b , i.e., the web range of the galvanometer system. Each of the preset areas is subjected to the film removal process respectively. That is, a first preset area is subjected to the film removal process, and after the completion thereof, a second preset area is subjected to the film removal process, and after the completion thereof, a third preset area is subjected to the film removal process, . . . , and so on, until the film removal process on all preset areas is completed. In these embodiments, the above step  650  is performed in each of the preset areas divided in the above S 630 . As shown in  FIG. 7 , for each of the preset areas where film is to be removed of the target object, S 650  is performed in the manner of S 651  described below. 
     S 651 , controlling the laser generator  310  to generate a laser beam, and controlling the first scanning galvanometer  312   a  and the second scanning galvanometer  312   b  to deflect, so that the laser beam is sequentially reflected by the first scanning galvanometer  312   a  and the second scanning galvanometer  312   b  to reach a preset area where the film is to be removed of the target object, thereby performing the film removal process on the preset area where the film is to be removed. 
     That is, the film removal method by the web splicing improves the problem of the film removal pattern distortion and improves the film removal quality. 
     For example, as shown in  FIG. 4( c ) , in some embodiments of the present disclosure, it is necessary to engrave  30  film removal engraved lines  320  parallel to the Y-axis on the solar cell  300 . At this time, the processing method for removing film includes the following steps  801  to  804  (S 801 -S 804 ). 
     S 801 , dividing the area of the solar cell to be removed film into three preset areas in the X direction, respectively being a preset area  420   a , a preset area  420   b , and a preset area  420   c.    
     S 802 , performing the above S 701 -S 707  to form  10  film removal engraved lines in the preset area  420   a.    
     S 803 , performing S 701 -S 707  described above, forming  10  film removal engraved lines in the preset area  420   b.    
     S 804 , performing S 701 -S 707  described above, forming  10  film removal engraved lines in the preset area  420   c.    
     In addition to the above-described multiple-face splicing manner, further solutions are provided in some embodiments such that the deflection angle of the first scanning galvanometer  312   a  is always less than or equal to the preset angle during the film removal process. In some embodiments, the processing method for removing film further includes: controlling the movement of a movable platform  32  while controlling the laser generator  310  to generate a laser beam and controlling the first scanning galvanometer  312   a  and the second scanning galvanometer  312   b  to deflect, such that the target object carried on the movable platform is moved. That is, as shown in  FIG. 8 , S 650  is performed in the manner of the following step  652  (S 652 ). 
     S 652 , controlling the laser generator  310  to turn on to generate laser beam, controlling the first scanning galvanometer  312   a  and the second scanning galvanometer  312   b  to deflect, and controlling the movement of the movable platform  32  to move the target object carried on the movable platform  32 , so that the laser beam is sequentially reflected by the first scanning galvanometer  312   a  and the second scanning galvanometer  312   b  to reach the target object, and the target object is subjected to the film removal process. 
     As shown in  FIG. 8 , in some embodiments, the processing method for removing film further includes step  620  (S 620 ). 
     S 620 , placing the target object on the movable platform  32 . 
     As shown in  FIG. 8 , in some embodiments, S 640  is performed in the manner of S 641  described below. 
     S 641 , moving the movable platform  32  or the optical component  31  including the laser generator  310 , the first scanning galvanometer  312   a , and the second scanning galvanometer  312   b  to a specified position. 
     In some embodiments of the present disclosure, the processing method for removing film includes: in the above S 652 , the scanning velocity of the laser beam reaching the target object through the first scanning galvanometer  312   a  and the second scanning galvanometer  312   b  is v 1 , and a component of the v 1  in the direction of the movement of the target object is the same as a velocity of the movement of the target object. 
     In some embodiments of the present disclosure, a scanning film removal process is achieved by controlling the movable platform  32  to drive the target object during the film removal process. Thus, even in the case where the multiple-face splicing is not employed, it is ensured that the deflection angle of the first scanning galvanometer  312   a  is always less than or equal to the preset angle. The film removal rate and the film removal quality are improved. 
     In some embodiments of the present disclosure, referring to  FIG. 3( b ) ,  FIG. 5( a ) , and  FIG. 5( b ) , it is necessary to engrave the film removal engraved line  320  on the solar cell  300 . The processing method for removing film includes the following steps  901 - 907 , and S 9040  (S 901 -S 907 , S 9040 ). 
     S 901 , placing a solar cell  300  on the movable platform  32 . 
     S 902 , moving the movable platform  32  or the optical component  31  including the laser generator  310 , the first scanning galvanometer  312   a , and the second scanning galvanometer  312   b  to a specified position. 
     S 903 , controlling the laser generator  310  to turn on and controlling the first scanning galvanometer  312   a  and the second scanning galvanometer  312   b  to deflect, so that the laser beam irradiating the solar cell  300  is in a first path inclined to the X-axis with respect to the XOY plane to scan; and controlling the movable platform  32  at the same time to drive the solar cell  300  to move at a constant velocity along the −X axis as shown in  FIG. 5( a ) . 
     A scanning velocity v 1  of the laser beam with respect to the XOY plane may be regarded as a combined velocity of a velocity v −x  along the −X axis and a velocity v −y  along the −Y axis. A velocity of the moving platform  32  driven by the solar cell  300  along the −X axis is v 3 , and satisfies v −X =v 3 . That is, with respect to the solar cell  300 , a velocity at which the laser beam engraves in the direction of the −X axis is 0, and a velocity at which the laser beam engraves in the −Y-axis direction is v −y . Thus, an engraved line parallel to the Y-axis is obtained on the solar cell  300 . 
     It is known that the first path described above is a scanning path of the laser beam with respect to the XOY plane. An angle α between the first path and the X-axis satisfies sin α=L/L 1 , where L is a length of the engraved line on the solar cell and L 1  is a length of the first path. 
     S 904 , controlling the laser generator  310  to turn off, and during the turn off of the laser generator  310 , controlling the movable platform  32  to drive the solar cell  300  to continue to move at a constant velocity along the −X axis. A duration of the laser generator  310  being turned off is W/v 3 , where W is a distance between two adjacent engraved lines. 
     S 905 , controlling the laser generator  310  to turn on, and controlling the first scanning galvanometer  312   a  and the second scanning galvanometer  312   b  to deflect, so that the laser beam illuminating the solar cell  300  is in a second path inclined to the X-axis relative to the XOY plane to scan. 
     At this time, a scanning velocity v 2  of the laser beam with respect to the XOY plane may be regarded as a combined velocity of a velocity v −x  along the −X axis and a velocity v y  along the Y axis (v y  and v −y  have the same magnitude and opposite direction), and satisfies v −y =v 3 . That is, with respect to the solar cell  300 , a velocity at which the laser beam engraves in the direction of the −X axis is 0, and a velocity at which the laser beam engraves in the Y-axis direction is v y . Thus, another engraved line parallel to the Y-axis is obtained on the solar cell  300 . Further, as shown in  FIG. 5( b ) , an angle between the second path and the −X axis is equal to the angle between the first path and the X-axis, and is also α. 
     S 906 , controlling the laser generator  310  to turn off, and during the turn off of the laser generator  310 , controlling the movable platform  32  to drive the solar cell  300  to continue to move at a constant velocity along the −X axis, and the duration of the laser generator  310  being turned off is W/v 3 . 
     S 907 , continuing the above S 903 -S 906  to perform the film removal process on the solar cell  300 . After a preset number of film removal engraved lines are formed, the film removal process is stopped, for example, stopped after the performance of S 903  or S 905 . 
     Further, in the above process, at least some of the periods during which the laser generator  310  is turned off, the following step  9040  is performed (S 9040 ). 
     S 9040 , controlling the first scanning galvanometer  312   a  to return to zero to ensure that the deflection angle is always less than or equal to the preset angle during the film removal process. 
     It should be noted that, in the case where the power of the laser generator  310  is less than the preset power, or the diameter of the laser beam irradiated on the solar cell  300  is smaller than the preset diameter, optionally, an engraved line is engraved more than once. 
     In some embodiments in which the engraving is performed twice, after S 903 , S 904  is not performed, instead of performing S 904 ′ described below, and then S 905  is performed. 
     S 904 ′, adjusting a scanning direction of the second scanning galvanometer  312   b.    
     Through the above steps, two sub-engraved lines completely coincided or partially coincided in the width direction are formed as an engraved line. 
     Proceeding to S 906  and S 907 ′ below. 
     S 907 ′, continuously performing S 903 , S 904 ′, S 905 , and S 906  to perform the film removal process on the solar cell  300 . After a preset number of film removal engraved lines are formed, the film removal process is stopped, for example, it is stopped after the performance of S 905 . 
     With a similar configure, an engraved line may be formed by scanning three times, four times, or even more times. 
     In some embodiments of the present disclosure, the processing method for removing film further includes: controlling a power when the laser generator is turned on to be larger than or equal to a preset power. 
     Using a higher power laser generator, the film removal rate is fast. Moreover, a plurality of film removal engraved lines may be quickly formed using a single laser head, which improves the chromatic aberration problem. 
     In some embodiments of the present disclosure, the processing method for removing film further includes: controlling a diameter of the laser beam irradiated on the target object to be larger than or equal to a preset diameter. 
     By controlling the diameter of the laser beam irradiated on the target object to be larger than or equal to the preset diameter, the number of times of film removal forming one engraving line can be reduced. That is, the film removal rate is increased. 
     The embodiments disclosed in the present disclosure are as described above, but are merely used to facilitate the understanding of the present disclosure, and are not intended to limit the present disclosure. Any modification and variation in the form and details of the implementation may be made by those skilled in the art without departing from the spirit and scope of the disclosure. The scope defined by the appended claims shall prevail.