Equipment for laser processing and method for compensating errors thereof

Abstract

Provided are an apparatus for laser processing and a method for compensating an error thereof. The apparatus for laser processing includes a stage supporting a substrate and a controller generating an error compensation table, a motor driver moving the stage, and an error compensation unit generating a table for compensating the error. The error compensation unit includes: a grid plate arranged on the stage and an imaging unit imaging the grid plate. The motor driver outputs a position synchronization signal to the imaging unit according to the position of the stage. The imaging unit receives the position synchronization signal from the motor driver and images the grid plate while moving the stage.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the priority of Korean Patent Application No. 10-2019-0008836 filed on January 23, 2019, in the Korean Intellectual Property Office (KIPO), the disclosure of which is incorporated herein by reference in its entirety. Technical Field

[0003] The present invention relates to an apparatus for laser processing and a method for compensating errors thereof. Background Art

[0004] A substrate (such as a display substrate used in a mobile phone) is grooved or cut using a laser processing device that irradiates the surface of the substrate. The laser processing device that cuts or grooves the substrate may have a focus of the laser adjusted by using a lens. However, due to the aberration of the lens, the laser emitted through the lens may become distorted, and the aberration of the lens may cause errors in the manufacturing process of the substrate. Summary of the invention

[0005] Embodiments of the present invention relate to an apparatus for laser processing configured to compensate for aberration- and movement-related errors caused during imaging of a continuously moving stage, and a method for implementing the same.

[0006] According to an exemplary embodiment of the present invention, there is provided an apparatus for laser processing, which includes a stage supporting a substrate, a controller generating an error compensation table, a motor driver moving the stage, and an error compensation unit generating a table for compensating errors. The error compensation unit includes a grid plate arranged on the stage and an imaging unit imaging the grid plate. The motor driver outputs a position synchronization signal to the imaging unit according to the position of the stage. The imaging unit receives the position synchronization signal from the motor driver and images the grid plate while moving the stage.

[0007] According to an exemplary embodiment of the present invention, whenever the stage moves a predetermined distance, the motor driver outputs a position synchronization signal. The generated error compensation table includes a movement error. The movement error included in the error compensation table indicates a difference between an actual distance traveled by the stage and a predetermined distance that occurs during a delay between the output of the position synchronization signal and the imaging of the grid plate.

[0008] According to an exemplary embodiment of the present invention, the controller analyzes the image imaged by the imaging unit to generate the error compensation table.

[0009] According to an exemplary embodiment of the present invention, the controller outputs a movement compensation signal based on the error compensation table.

[0010] According to an exemplary embodiment of the present invention, the grid plate includes a reflective material, and light from the lighting unit is provided to the grid plate through coaxial lighting.

[0011] According to an exemplary embodiment of the present invention, the lighting unit includes a light source driven at a power of at least 3W.

[0012] According to an exemplary embodiment of the present invention, the imaging unit includes a high-speed camera that images at a frame rate of at least 60 frames per second (fps).

[0013] According to an exemplary embodiment of the present invention, an apparatus for laser processing includes a laser beam generator disposed on a stage, a galvanometer scanner unit receiving a laser beam from the laser beam generator, and a lens unit disposed between the galvanometer scanner unit and the stage.

[0014] According to an exemplary embodiment of the present invention, an apparatus for laser processing includes a lens unit including at least one of a telecentric lens and an F-theta lens.

[0015] According to an exemplary embodiment of the present invention, a method for compensating for errors of an apparatus for laser processing includes: forming a grid plate on a mother board; moving a stage on which the grid plate is arranged; generating a position synchronization signal whenever the stage moves a predetermined distance; imaging the grid plate in response to the position synchronization signal; and generating an aberration compensation table by calculating errors caused by aberrations.

[0016] According to an exemplary embodiment of the present invention, the grid plate is imaged during stage movement in response to a position synchronization signal.

[0017] According to an exemplary embodiment of the present invention, the method of compensating for an error of an apparatus for laser processing further includes outputting a stage movement compensation signal after generating an aberration compensation table by calculating the error.

[0018] According to an exemplary embodiment of the invention, imaging the grid plate in response to the position synchronization signal includes imaging the grid plate at a frame rate of at least 30 frames per second (fps).

[0019] According to an exemplary embodiment of the present invention, forming a grid plate includes forming a grid on a mother board.

[0020] According to an exemplary embodiment of the present invention, a grid plate includes a reflective material and a plurality of orthogonal wires.

[0021] According to an exemplary embodiment of the present invention, a method for compensating an error of an apparatus for laser processing includes: after generating an aberration compensation table by calculating an error caused by an aberration, calculating an error caused by the movement of a stage. Calculating the error caused by the movement of the stage includes: moving the stage discontinuously and linearly during a first pass; generating a position synchronization signal when the stage stops at a position corresponding to an intersection of a grid plate; imaging the grid plate in response to the position synchronization signal during the stop of the stage; moving the stage continuously during a second pass; generating a position synchronization signal when the stage moves a predetermined distance; imaging the grid plate in response to the position synchronization signal during the movement of the stage; and calculating the error to generate a movement error compensation table.

[0022] According to an exemplary embodiment of the present invention, when calculating errors to generate a motion error compensation table, the errors are filtered in an area where the stage is accelerating or decelerating.

[0023] According to an exemplary embodiment of the present invention, when calculating errors to generate a movement error compensation table, the errors are calculated by comparing and analyzing images of the grid plates, and the errors are calculated in a region where the stage moves at a constant speed.

[0024] According to an exemplary embodiment of the present invention, a method for compensating for errors of an apparatus for laser processing is provided. The method includes positioning a grid on a stage; discontinuously moving the stage during a first pass; and continuously moving the stage during a second pass. Discontinuously moving the stage during the first pass includes generating a position synchronization signal when the stage stops at a position corresponding to an intersection of the grid; and imaging the grid in response to the position synchronization signal while the stage is stopped. Continuously moving the stage during the second pass includes generating a position synchronization signal each time the stage moves a predetermined distance in a first direction during the movement of the stage; imaging the grid in response to the position synchronization signal during the movement of the stage; and calculating each error to generate a movement error compensation table. The intersection of the grid corresponds to the predetermined distance.

[0025] According to an exemplary embodiment of the present invention, when calculating errors to generate a motion error compensation table, the errors are filtered in an area where the stage is accelerating or decelerating.

[0026] According to an exemplary embodiment of the present invention, when calculating the error to generate the movement error compensation table, the error is calculated in a region where the stage moves at a constant speed.

[0027] The foregoing is merely illustrative and is not intended to be limiting in any way. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The above and other aspects and features of the present disclosure will be more clearly understood through the following detailed description taken in conjunction with the accompanying drawings, in which:

[0029] Figure 1 is a schematic diagram showing a laser processing apparatus according to an exemplary embodiment of the present invention;

[0030] Figure 2 is a flowchart illustrating an algorithm for generating an aberration error compensation table according to the aberration of a laser processing device according to an exemplary embodiment of the present invention;

[0031] Figure 3 is a table view showing an imaging path of a grid plate corresponding to a stage that is continuously moved and a position where a synchronization signal of a laser processing device is generated to capture an image according to an exemplary embodiment of the present invention;

[0032] Figure 4 is a flowchart illustrating an algorithm for generating a movement error compensation table according to the movement of a stage of a laser processing device according to an exemplary embodiment of the present invention;

[0033] Figure 5 FIG. 2 is a diagram showing a method including an acceleration area and a deceleration area according to an exemplary embodiment of the present invention. Figure 4 A generated tabular view of the motion error compensation table;

[0034] Figure 6 is a diagram showing an exemplary embodiment according to the present invention Figure 5 a generated tabular view of a filtered version of a motion error compensation table;

[0035] Figure 7 is a comparative graphical view showing processing time according to resolution of a grid plate in a comparative laser processing apparatus; and

[0036] Figure 8 is a graphical view illustrating a processing time according to a resolution of a grid plate in a laser processing apparatus according to an exemplary embodiment of the present invention. DETAILED DESCRIPTION

[0037] The present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which various exemplary embodiments are shown. However, the present invention may be embodied in many different forms and should not be construed as limited to the exemplary embodiments set forth herein.

[0038] Throughout the following description and drawings, the same reference numerals may indicate the same elements. In addition, in order to facilitate the description of technical contents, the thickness, ratio and size of elements in the drawings may be exaggerated.

[0039] Figure 1Schematic diagram of a laser processing device according to an exemplary embodiment of the present invention. Figure 1 An exemplary embodiment of a laser processing apparatus is described in detail.

[0040] The laser processing apparatus includes a stage 10, a laser beam generator 20, a galvanometer scanner unit 30, a lens unit 40, a controller 50, a motor driver 60, and an error compensation unit (the error compensation unit may collectively refer to a grid plate 100, an imaging unit 200, and an illumination unit 300).

[0041] The stage 10 is configured to move in a first direction (eg, D1 direction) and / or a second direction (eg, D2 direction) perpendicular to the first direction (eg, D1 direction) by a motor driver 60 , which will be described in further detail below.

[0042] The laser beam generator 20 emits a laser beam toward the galvanometer scanner unit 30. The laser beam generator 20 may emit the laser beam continuously or discontinuously. The laser beam includes a single beam or a plurality of beams.

[0043] According to an exemplary embodiment of the present invention, a beam splitter is positioned between the laser beam generator 20 and the galvanometer scanner unit 30. The beam splitter may split the laser beam into a plurality of laser beams and guide paths of the respective laser beams.

[0044] The galvanometer scanner unit 30 may adjust the directional path of at least one of the plurality of laser beams incident to the galvanometer scanner unit 30 to direct at least one laser beam to a desired position on the substrate to be processed. For example, the galvanometer scanner unit 30 directs the laser beam toward the substrate or the grid plate 100 arranged on the stage 10. The grid plate 100 may have a plurality of first lines and second lines. The first lines extend substantially in a first direction (e.g., D1 direction) and are spaced apart from each other by a first interval in a second direction (e.g., D2 direction). The second lines may extend substantially in a second direction (e.g., D2 direction) and are spaced apart from each other by a second interval in a first direction (e.g., D1 direction). Each of the first interval and the second interval represents a distance between the intersections of the first line and the second line. However, the present invention is not limited thereto. For example, each unit or intersection of the grid plate 100 may be composed of a ring and a point, the point being positioned at the center of the ring and spaced apart from the outer periphery of the ring by the radius of the ring. The galvanometer scanner unit 30 includes a plurality of galvanometers, and the plurality of galvanometers are arranged at a predetermined angle relative to each other. The angle of each galvanometer mirror is adjustable to direct the laser beam toward a specific location of a substrate disposed on stage 10 .

[0045] The lens unit 40 may be disposed between the stage 10 and the galvanometer scanner unit 30. For example, the lens unit 40 is disposed between the galvanometer scanner unit 30 and the substrate or grid plate 100. The lens unit 40 converges the laser beam provided from the galvanometer scanner unit 30 and directs the laser beam onto the substrate or grid plate 100.

[0046] The lens unit 40 includes at least one condensing lens. Hereinafter, it is assumed that the lens unit 40 includes one condensing lens. However, the present invention is not limited thereto. For example, the lens unit 40 may include a plurality of condensing lenses.

[0047] The condenser lens of the lens unit 40 converges the laser beam generated from the laser beam generator 20 and guides the laser beam to the substrate to be processed or the grid plate 100. For example, the condenser lens may be a telecentric lens or an F-θ lens. The focal length of the condenser lens is determined in consideration of, for example, a plurality of galvanometers included in the galvanometer scanner unit 30, the substrate to be processed, and the grid plate 100.

[0048] The substrate to be processed may include, for example, a substrate and / or glass. However, the present invention is not limited thereto. The substrate may be arranged on the stage 10.

[0049] The controller 50 controls operations of the stage 10 , the laser beam generator 20 , the galvanometer scanner unit 30 , and / or the motor driver 60 .

[0050] According to an exemplary embodiment of the present invention, the controller 50 analyzes the image imaged by the imaging unit 200 to generate an error compensation table. The error compensation signal may be output to the galvanometer scanner unit 30 and / or the motor driver 60 based on the generated error compensation table.

[0051] The motor driver 60 may be configured to move the stage 10 in a first direction (eg, D1 direction) and / or a second direction (eg, D2 direction) The motor driver 60 outputs a signal for moving the stage 10 .

[0052] The motor driver 60 is directly connected to the imaging unit 200, which will be described below. The motor driver 60 outputs a position synchronization signal (which may also be referred to as a "position synchronization output (PSO)" or a "position synchronization signal") based on the position and / or movement distance of the stage 10. The motor driver 60 outputs the PSO whenever the stage 10 moves a predetermined distance (e.g., a specified number of first intervals and / or second intervals) in the first direction (e.g., D1 direction) and / or the second direction (e.g., D2 direction). For example, the motor driver 60 may output the PSO whenever the imaging unit 200 reaches the intersection of the first line and the second line.

[0053] According to an exemplary embodiment of the present invention, when the position of the stage 10 is synchronized with the position (eg, the cross point) of the grid plate 100 , the motor driver 60 outputs the PSO to the imaging unit 200 , and the imaging unit 200 captures an image.

[0054] The error compensation unit includes a grid plate 100 , an imaging unit 200 and an illumination unit 300 .

[0055] The grid plate 100 includes a grid formed by a laser processing device. For example, the grid plate 100 may be composed of a first line and a second line.

[0056] The grid plate 100 may include a material having a high reflectivity. For example, the grid plate 100 may be a mirror including aluminum (Al). Accordingly, the grid plate 100 may reflect light emitted by the lighting unit 300 to be described below with a high reflectivity. For example, light reflected from the surface of the grid plate 100 may be provided to the imaging unit 200 by coaxial illumination. Therefore, the imaging unit 200 may accurately capture an image of a grid formed on the grid plate 100.

[0057] The imaging unit 200 captures an image of the grid plate 100 arranged on the stage 10. For example, the imaging unit 200 may receive a PSO and capture an image of the grid plate 100 whenever the stage 10 moves a predetermined distance in the first direction (e.g., D1 direction) and / or the second direction (e.g., D2 direction) while the stage 10 continuously moves without stopping in the first direction (e.g., D1 direction) and / or the second direction (e.g., D2 direction).

[0058] The imaging unit 200 may include a high-speed camera. The high-speed camera of the imaging unit 200 may capture images at a speed of at least 30 frames per second (fps). For example, the high-speed camera of the imaging unit 200 may capture images at a speed of at least 60 fps. Accordingly, the imaging unit 200 may accurately capture an image of the grid plate 100 during the movement of the stage 10.

[0059] The lighting unit 300 provides light for more accurately imaging the substrate or grid plate 100 disposed on the stage 10. For example, the lighting unit 300 may be a white light emitting diode (LED) light source. However, the present invention is not limited thereto, and the lighting unit 300 may include light sources of different colors.

[0060] The lighting unit 300 is arranged adjacent to the lens unit 40 .

[0061] According to an exemplary embodiment of the present invention, the light source of the lighting unit 300 may have a power consumption of about 3 W or more, and may prevent motion blur that occurs when the grid plate 100 is imaged while continuously moving.

[0062] In the following, reference will be made to Figure 2and Figure 3 A method of compensating for an error that may be caused by an aberration of a lens in a laser processing apparatus according to an exemplary embodiment of the present invention is described in detail.

[0063] Figure 2 is a flowchart showing an algorithm for generating an error compensation table according to an aberration of a laser processing device according to an exemplary embodiment of the present invention, and Figure 3 is a table view illustrating an imaging path of a grid plate corresponding to a stage that is continuously moved and a position at which a position synchronization signal of a laser processing apparatus is generated to capture an image according to an exemplary embodiment of the present invention.

[0064] First, a grid may be formed on a mother board to form the grid plate 100 (S11). The grid may be formed by etching performed by a laser processing device, however the inventive concept is not limited thereto. The grid may be formed by intersecting first and second lines extending in a first direction (e.g., D1 direction) and a second direction (e.g., D2 direction), respectively. The intersection of the grid may correspond to a predetermined movement distance of the stage, at which the motor driver 60 is programmed to generate a PSO that prompts the imaging unit 200 to capture an image. According to an exemplary embodiment of the present invention, a filter or lens of the imaging unit 200 may be designed to include preformed lines that operate as grid marks. As Figure 3 As shown in , the laser processing device can form a grid plate 100 including a grid in the form of a 4-row and 7-column matrix including a first horizontal line H1, a second horizontal line H2, a third horizontal line H3, and a fourth horizontal line H4 (also referred to herein as rows) and a first vertical line V1, a second vertical line V2, a third vertical line V3, a fourth vertical line V4, a fifth vertical line V5, a sixth vertical line V6, and a seventh vertical line V7 (also referred to herein as columns). However, the present invention is not limited thereto, and the size of the grid may be variously changed.

[0065] Thereafter, the motor driver 60 may move the stage 10 to the starting point (S12). For example, the motor driver 60 may move the stage 10 so that the imaging unit 200 is arranged at a position corresponding to one of a plurality of intersections of horizontal lines and vertical lines of a grid extending in a first direction (e.g., D1 direction) and a second direction (e.g., D2 direction), respectively. Figure 3 As shown in , the motor driver 60 may move the stage 10 , and the imaging unit 200 may be arranged at a position corresponding to the start point SP located adjacent to the grid plate 100 .

[0066] The motor driver 60 may cause the stage 10 to continuously and linearly move in the first direction (e.g., D1 direction) and / or the second direction (e.g., D2 direction) (S13). The motor driver 60 may cause the stage 10 to linearly move in the first direction (e.g., D1 direction) and / or the second direction (e.g., D2 direction) without stopping until the stage 10 reaches the end of the grid. For example, Figure 3 As shown in , the motor driver 60 can move the stage 10 continuously and linearly without stopping from a starting point SP located adjacent to a corner of the grid plate 100 to a diagonal or opposite corner of the grid plate 100 along a first direction (e.g., D1 direction). Although the path of the stage 10 is shown as a uniform continuous motion on each horizontal row, the present invention is not limited thereto. For example, the continuous linear motion exhibited by the stage 10 may include a zigzag between adjacent rows and / or columns, or may involve a variable path.

[0067] Whenever the stage 10 moves a predetermined distance in the first direction (eg, D1 direction) and / or the second direction (eg, D2 direction), the motor driver 60 may output a PSO (S14). Figure 3 As shown in , as the stage 10 continues to move without stopping, the motor driver 60 may output the PSO whenever the stage 10 is located at a position corresponding to an intersection of the grid aimed at by the imaging unit 200 .

[0068] The motor driver 60 may output the PSO to the imaging unit 200 , and the imaging unit 200 may receive the PSO generated from the motor driver 60 .

[0069] The imaging unit 200 may receive the PSO from the motor driver 60 and continue to capture an image of the grid plate 100 (S15). The PSO input from the motor driver 60 may be applied as a trigger signal for causing the imaging unit 200 to capture an image. While the stage 10 is continuously moving, the imaging unit 200 may capture an image of the grid plate 100 at a fast shutter speed, thereby substantially preventing motion blur from occurring in the captured image of the grid plate 100. For example, the imaging unit 200 may capture an image of the grid plate 100 at a shutter speed of about 10 μs.

[0070] According to an exemplary embodiment of the present invention, Figure 3 As shown in , when the stage 10 is moved a predetermined distance by the motor driver 60, the motor driver 60 may output the PSO to the imaging unit 200, and the imaging unit 200 may capture an image of the grid plate 100 at intersections between the first horizontal line H1 and the first vertical line V1, the second vertical line V2, the third vertical line V3, the fourth vertical line V4, the fifth vertical line V5, the sixth vertical line V6, and the seventh vertical line V7.

[0071] According to an exemplary embodiment of the present invention, since the stage 10 can move without stopping during the period when the imaging unit 200 captures the image of the grid plate 100, the time consumed in capturing the image of the grid plate 100 can be greatly reduced, which will be referred to below. Figure 7 and Figure 8 Describe in detail.

[0072] The controller 50 may analyze the positions of the intersections imaged between the first horizontal line H1 and the first vertical line V1, the second vertical line V2, the third vertical line V3, the fourth vertical line V4, the fifth vertical line V5, the sixth vertical line V6, and the seventh vertical line V7, and the positions of the intersections between the first horizontal line H1 and the first vertical line V1, the second vertical line V2, the third vertical line V3, the fourth vertical line V4, the fifth vertical line V5, the sixth vertical line V6, and the seventh vertical line V7 to identify aberration-related errors, and may generate an aberration compensation table for correcting aberration errors. According to the aberration compensation table, the controller 50 may output a position movement compensation signal for correcting the movement of the motor driver 60, the galvanometer scanner unit 30, and / or the motor driver 60, so that the aberration error can be corrected (S16). The aberration error may indicate a deviation of a line of a grid or a converged laser beam irradiated onto the surface of a substrate from an ideal path. For example, an image showing that the convergence point of the laser beam does not overlap at right angles with the intersection or exceeds the boundary may indicate an aberration error.

[0073] In the following, reference will be made to Figure 4 , Figure 5 and Figure 6 A method of compensating for the movement error of the stage 10 is described in detail.

[0074] Figure 4 is a flowchart illustrating an algorithm for generating a movement error compensation table based on the movement of a stage in a laser processing apparatus according to an exemplary embodiment of the present invention.

[0075] Figure 5 FIG. 2 is a diagram showing a method including an acceleration area and a deceleration area according to an exemplary embodiment of the present invention. Figure 4 A generated tabular view of the motion error compensation table.

[0076] According to an exemplary embodiment of the present invention, the imaging unit 200 may receive the PSO from the motor driver 60, and may capture an image of the grid plate 100. However, a delay may occur after the motor driver 60 outputs the PSO until the imaging unit 200 captures the image of the grid plate 100. Accordingly, an error may occur due to a difference between the position of the imaging unit 200 when the PSO is generated and the position where the imaging unit 200 actually captures the image. For example, when the moving speed of the stage 10 is accelerated or decelerated, the above-mentioned delay and error may increase. According to an exemplary embodiment of the present invention, a movement error compensation table for correcting the above-mentioned movement error may be generated.

[0077] Reference Figure 4 The motor driver 60 can move the stage 10 discontinuously and linearly (S21). Figure 5 As shown in , the motor driver 60 can move the stage 10, and when the imaging unit 200 is located at a position corresponding to an intersection of the grid, the motor driver 60 can stop the stage 10 for a predetermined time, and then after the predetermined time has passed, can move the stage 10 again until it reaches the next intersection. The curved arrows represent the moving distance intervals of the stage 10 between the intersections when the movement synchronization signal is generated. The accompanying table shows the moving distance of the stage 10 when the PSO is generated at each interval, the actual moving distance of the stage 10 at each interval, and the movement error associated with each specific interval. The imaging unit 200 can be located at a position corresponding to an intersection of the grid, and the motor driver 60 can stop the stage 10 for a predetermined time, and then move the stage 10 in a straight line again. For example, as Figure 5 As shown in , whenever the imaging unit 200 is located at a position corresponding to a point where the third horizontal line H3 intersects the first vertical line V1, the second vertical line V2, the third vertical line V3, the fourth vertical line V4, the fifth vertical line V5, the sixth vertical line V6, the seventh vertical line V7, the eighth vertical line V8, and the ninth vertical line V9, respectively, the motor driver 60 may stop the stage 10 for a predetermined time and then move the stage 10 linearly again.

[0078] Whenever the stage 10 moves a certain distance, the motor driver 60 may output PSO (S22). Figure 5 As shown in , whenever the imaging unit 200 is located at an intersection of the grid, the motor driver 60 may generate a PSO, and the stage 10 may stop. For example, whenever the imaging unit 200 is located at a position corresponding to a point where the third horizontal line H3 intersects the first vertical line V1, the second vertical line V2, the third vertical line V3, the fourth vertical line V4, the fifth vertical line V5, the sixth vertical line V6, the seventh vertical line V7, the eighth vertical line V8, and the ninth vertical line V9, respectively, the motor driver 60 may generate a PSO, and the stage 10 may stop.

[0079] According to an exemplary embodiment of the present invention, the imaging unit 200 may receive the PSO and may capture an image of the grid plate 100. For example, Figure 5 As shown in , whenever the imaging unit 200 is located at a position corresponding to a point where the third horizontal line H3 intersects the first vertical line V1, the second vertical line V2, the third vertical line V3, the fourth vertical line V4, the fifth vertical line V5, the sixth vertical line V6, the seventh vertical line V7, the eighth vertical line V8, and the ninth vertical line V9, respectively, the stage 10 may stop for a predetermined time. The imaging unit 200 may receive the PSO from the motor driver 60, and may capture an image of the grid plate 100 at a point where the third horizontal line H3 intersects the first vertical line V1, the second vertical line V2, the third vertical line V3, the fourth vertical line V4, the fifth vertical line V5, the sixth vertical line V6, the seventh vertical line V7, the eighth vertical line V8, and the ninth vertical line V9, respectively.

[0080] The motor driver 60 may move the stage 10 in a continuous linear motion (S24). For example, the motor driver 60 may move the stage 10 linearly without stopping until it reaches the end of the grid. Figure 5 As shown in FIG. 1 , the motor driver 60 can move the stage 10 linearly and continuously from the starting point SP without stopping.

[0081] According to an exemplary embodiment of the present invention, the motor driver 60 may output a PSO (S25) whenever the stage 10 moves a predetermined distance. For example, whenever the imaging unit 200 is located at a position corresponding to an intersection of the grid, the motor driver 60 may generate a PSO. For example, during the movement of the stage 10, whenever the stage 10 moves a predetermined distance (e.g., an interval between intersections), the motor driver 60 outputs a PSO to the imaging unit 200.

[0082] The imaging unit 200 having received the PSO from the motor driver 60 may capture an image of the grid plate 100 (S26). For example, during the movement of the stage 10 without stopping, whenever the stage 10 moves a predetermined distance (e.g., the interval between the intersections), the imaging unit 200 may receive the PSO and capture an image of the grid plate 100. For example, whenever the imaging unit 200 is located at a position corresponding to a point where the third horizontal line H3 intersects the first vertical line V1, the second vertical line V2, the third vertical line V3, the fourth vertical line V4, the fifth vertical line V5, the sixth vertical line V6, the seventh vertical line V7, the eighth vertical line V8, and the ninth vertical line V9, respectively, the imaging unit 200 may receive the PSO and may capture an image of the grid plate 100 at a point where the third horizontal line H3 intersects the first vertical line V1, the second vertical line V2, the third vertical line V3, the fourth vertical line V4, the fifth vertical line V5, the sixth vertical line V6, the seventh vertical line V7, the eighth vertical line V8, and the ninth vertical line V9, respectively.

[0083] The controller 50 may generate a movement error compensation table and apply the movement error compensation table to correct the error (S27). Figure 5 As shown in , the controller 50 compares and analyzes the corresponding captured images from the continuous segment and the discontinuous segment to identify the movement error between them, and can generate a movement error compensation table for correcting the movement error during a specific interval including the interval arranged in the acceleration area and the deceleration area. According to the movement error compensation table, a position movement compensation signal for correcting the movement of the motor driver 60 can be output to the galvanometer scanner unit 30 and / or the motor driver 60.

[0084] Figure 6 is a diagram showing an exemplary embodiment according to the present invention Figure 5 A generated tabular view of a filtered version of the motion error compensation table.

[0085] The imaging unit 200 may receive the PSO from the motor driver 60 and may capture an image of the grid plate 100. After the motor driver 60 outputs the PSO, a delay may occur until the imaging unit 200 captures an image of the grid plate 100. Accordingly, since there is a movement error between the position of the stage 10 when the PSO is generated and the position where the imaging unit 200 actually captures the image, a movement-related imaging error may occur. For example, Figure 5 and Figure 6 As shown in , when the moving speed of the stage 10 changes (there are acceleration areas and deceleration areas), the above-mentioned imaging delay and the associated movement error increase. On the other hand, when the moving speed of the stage 10 is constant (constant speed area), the above-mentioned imaging delay and the associated movement error between the intersections may be constant. According to an exemplary embodiment of the present invention, data related to the acceleration area and the deceleration area of ​​the stage 10 may be filtered to block the movement synchronization signal at the acceleration area and the deceleration area of ​​the stage 10, thereby facilitating simple correction of the movement error. Accordingly, the above-mentioned movement error compensation table may be generated only for the constant speed area where the movement error is constant, and the constant movement error of the constant speed area may be corrected relatively easily. The designated imaging time of the stage 10 may be adjusted by the motor driver 60 in the constant speed area taking into account the calculated movement error, so as to accurately image the intersection and avoid the associated imaging error. For example, considering the expected imaging delay time, the PSO may be output by the motor driver 60 before or after a predetermined moving distance (e.g., the associated intersection) of the stage 10. The modified PSO timing may be determined by the controller 50.

[0086] Figure 7 is a graphical view showing processing time according to the resolution of a grid used in a comparative laser processing apparatus, and Figure 8is a graphical view illustrating a processing time according to a resolution of a grid in a laser processing apparatus according to an exemplary embodiment of the present invention.

[0087] Figure 7 A comparative graph showing the time consumed to correct the movement error at the intersection of the grid where the stage 10 does not move continuously and linearly as the imaging unit 200 stops each time the imaging unit 200 is located at the position corresponding to the intersection of the grid is shown. In the case where the stage 10 does not move continuously and linearly as the motor driver 60 stops each time the imaging unit 200 is located at the position corresponding to the intersection of the grid, the time consumed to correct the movement error between the intersections of the grid is proportional to the square of the resolution of the grid. As shown in Table 1, as the resolution increases, the time required to correct the error increases exponentially.

[0088]

Table 1

[0089]

[0090]

[0091] Figure 8 A graph showing the time consumed to correct movement errors at intersections of the grid according to resolution is shown in the case where the imaging unit 200 captures an image of the grid plate 100 during the continuous movement of the stage 10. When the imaging unit 200 captures an image of the grid plate 100 during the continuous movement of the stage 10, the time consumed to correct errors detected at intersections of the grid is linearly proportional to the resolution of the grid. Compared to the case where the stage 10 does not move continuously and linearly as depicted in Table 1 shown above, as shown in Table 2, the time consumed to correct errors according to the laser processing apparatus and error compensation method described herein is much lower at all grid resolutions.

[0092]

Table 2

[0093]

[0094] Accordingly, the present invention reduces the amount of time required to accurately manufacture a display device and can therefore increase productivity and accuracy.

[0095] While exemplary embodiments of the present invention have been shown and described above, it will be understood by those skilled in the art that modifications and changes in form and details may be made without departing from the spirit and scope of the invention.

Claims

1. A device for laser processing, comprising: a stage supporting a substrate; A controller, the controller generating an aberration compensation table and a motion error compensation table; a motor drive that moves the stage; as well as Error compensation unit, Wherein, the error compensation unit comprises: a grid plate disposed on the table; and an imaging unit, wherein the imaging unit images the grid plate, wherein the motor driver outputs a position synchronization signal to the imaging unit according to the position of the stage, wherein, in a discontinuous section of the discontinuous movement of the stage, the imaging unit receives the position synchronization signal from the motor driver and images a plurality of intersections of the grid plate during stopping of the stage, wherein, during a continuous section of the continuous movement of the stage, the imaging unit receives the position synchronization signal from the motor driver and images the plurality of intersections of the grid plate during the movement of the stage, wherein the generated motion error compensation table includes motion errors calculated by comparing images of the plurality of intersections of the grid plates from the continuous segment with corresponding images of the plurality of intersections of the grid plates from the discontinuous segment, and Wherein, the aberration compensation table is generated based on the images of the plurality of intersection points of the grid plate from the continuous segment.

2. The laser processing apparatus according to claim 1, wherein: The motor driver outputs the position synchronization signal each time the stage moves a predetermined distance, and wherein the movement error included in the movement error compensation table indicates a difference between an actual distance traversed by the stage and the predetermined distance occurring during a delay between the output of the position synchronization signal and the imaging of the grid plate.

3. The laser processing apparatus according to claim 1, wherein: The controller analyzes the image imaged by the imaging unit to generate the movement error compensation table.

4. The laser processing apparatus according to claim 3, wherein: The controller outputs a motion compensation signal based on the motion error compensation table.

5. The apparatus for laser processing according to claim 1, wherein: The grid plate includes a reflective material, and light from a lighting unit is provided to the grid plate by coaxial lighting.

6. The apparatus for laser processing according to claim 5, wherein: The lighting unit includes a light source driven at a power of at least 3W.

7. The apparatus for laser processing according to claim 1, wherein: The imaging unit includes a high-speed camera that images at a frame rate of at least 60 frames per second.

8. The laser processing apparatus according to claim 1, further comprising: a laser beam generator, the laser beam generator being arranged on the table; a galvanometer scanner unit, the galvanometer scanner unit receiving the laser beam from the laser beam generator; as well as A lens unit is disposed between the galvanometer scanner unit and the stage.

9. The apparatus for laser processing according to claim 8, wherein: The lens unit includes at least one of a telecentric lens and an F-θ lens.

10. A method for compensating for errors in a device for laser processing, the method comprising: forming a grid plate on a mother board; moving the table on which the grid plate is arranged; generating a position synchronization signal each time the stage moves a predetermined distance; imaging the grid plate in response to the position synchronization signal; generating an aberration compensation table by calculating errors caused by aberrations; as well as calculating a movement error caused by the movement of the stage by comparing images of a plurality of intersections of the grid plates from a continuous segment of continuous movement of the stage with corresponding images of the plurality of intersections of the grid plates from a discontinuous segment of discontinuous movement of the stage, wherein, in the non-continuous section, the plurality of intersections of the grid plate are imaged while the stage is stopped in response to the position synchronization signal, and in the continuous section, the plurality of intersections of the grid plate are imaged while the stage is moved in response to the position synchronization signal, and Wherein, the aberration compensation table is generated based on the images of the plurality of intersection points of the grid plate from the continuous segment.

11. The method of claim 10, wherein: The grid plate is imaged during movement of the stage in response to the position synchronization signal.

12. The method of claim 10, further comprising: After the aberration compensation table is generated by calculating the error, a stage movement compensation signal is output.

13. The method of claim 10, wherein: Imaging the grid plate in response to the position synchronization signal comprises: The grid plate is imaged at a frame rate of at least 30 frames per second.

14. The method of claim 10, wherein: Forming the grid plate comprises: forming a grid on the motherboard; Wherein, the grid plate comprises a reflective material, and Wherein, the grid plate comprises a plurality of orthogonal lines.

15. The method of claim 10, wherein: Calculating the movement error caused by the movement of the stage comprises: causing the stage to move discontinuously and linearly during a first pass; generating a position synchronization signal when the stage stops at a position corresponding to an intersection of the grid plates; imaging the grid plate in response to the position synchronization signal while the stage is stopped; continuously moving the stage during the second pass; generating a position synchronization signal when the stage moves a predetermined distance; imaging the grid plate in response to the position synchronization signal during movement of the stage; and The motion error is calculated to generate a motion error compensation table.

16. The method of claim 15, wherein: When calculating the motion errors to generate the motion error compensation table, the motion errors are filtered in areas where the stage is accelerating or decelerating.

17. The method of claim 15, wherein: In calculating the movement error to generate the movement error compensation table, the movement error is calculated by comparing and analyzing the images of the grid plate, and the movement error is calculated in a region where the stage moves at a constant speed.

18. A method for compensating for errors in a device for laser processing, the method comprising: Positioning grid plate on stage; Discontinuously moving the stage during the first pass, wherein discontinuously moving the stage during the first pass comprises: generating a position synchronization signal when the stage stops at a position corresponding to an intersection of the grid plates; and imaging the grid plate in response to the position synchronization signal while the stage is stopped; and continuously moving the stage during the second pass, wherein continuously moving the stage during the second pass comprises: generating a position synchronization signal each time the stage moves a predetermined distance in a first direction while moving the stage; imaging the grid plate in response to the position synchronization signal while moving the stage; and calculating each motion error by comparing images of a plurality of intersections of the grid plate imaged during movement of the stage with corresponding images of the plurality of intersections of the grid plate imaged during stoppage of the stage to generate a motion error compensation table, Wherein, the intersection points of the grid plates correspond to the predetermined distances.

19. The method of claim 18, wherein: When calculating the motion errors to generate the motion error compensation table, the motion errors are filtered in areas where the stage is accelerating or decelerating.

20. The method of claim 18, wherein: In calculating the movement error to generate the movement error compensation table, the movement error is calculated in a region where the stage moves at a constant speed.

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