Laser repair apparatus and laser repair method

Abstract

According to embodiments, a laser repair device for repairing defects in an object comprises: a laser beam generator that emits a laser beam; a beam expander that receives the laser beam and emits a laser beam with an expanded cross-sectional area; a digital micro-mirror device comprising a plurality of micro-mirrors that receive the laser beam emitted from the beam expander and disperse it into multiple beams; and a lens unit that receives the multiple beams, converges them, and irradiates them onto the object, wherein the cross-section of the laser beam incident on the digital micro-mirror device has a size capable of covering the entire area of ​​the plurality of micro-mirrors.

Description

Technology Field

[0001] The present disclosure relates to a laser repair device and a laser repair method. Background Technology

[0002] Display devices such as liquid crystal displays (LCDs) and organic light emitting diode displays (OLEDs) include a display panel comprising a plurality of pixels capable of displaying an image and a plurality of signal lines, and a cover window for protecting the display panel. Each pixel includes a pixel electrode that receives a data signal, and the pixel electrode is connected to at least one transistor to receive the data signal.

[0003] The display panel may include a substrate and a plurality of thin film layers stacked on the substrate. The thin film layers may include a wiring pattern. Defects occurring in the wiring pattern can be repaired using a laser repair device. The problem to be solved

[0004] The embodiments can provide a laser repair device and a laser repair method that can improve the lifespan of a digital micromirror device (DMD). means of solving the problem

[0005] A laser repair device according to one embodiment is a laser repair device for repairing defects in an object, comprising: a laser beam generator that emits a laser beam; a beam expander that receives the laser beam and emits a laser beam with an expanded cross-sectional area; a digital micro-mirror device comprising a plurality of micro-mirrors that receive the laser beam emitted from the beam expander and disperse it into multiple beams; and a lens unit that receives the multiple beams, converges them, and irradiates them onto the object, wherein the cross-section of the laser beam incident on the digital micro-mirror device has a size capable of covering the entire area of ​​the plurality of micro-mirrors.

[0006] The laser beam emitted from the above laser beam generating unit may include a plurality of wavelengths.

[0007] It may further include a filter located between the laser beam generator and the beam expander, which blocks some of the wavelengths among the plurality of wavelengths included in the laser beam emitted from the laser beam generator.

[0008] The cross-sectional area of ​​the laser beam incident on the digital micro-mirror device may have a size ranging from 2 to 16 times the total area of ​​the plurality of micro-mirrors.

[0009] The cross-section of the laser beam incident on the digital micro-mirror device includes a center and an outer portion surrounding the center, and may further include an aperture located between the beam expander and the digital micro-mirror device that blocks the outer portion of the laser beam incident on the digital micro-mirror device.

[0010] The aperture may be configured to reduce the cross-sectional area of ​​the laser beam incident on the digital micro-mirror device by 50% to 80%.

[0011] The intensity of the above center may be 86.5% or more of the maximum intensity of the laser beam incident on the digital micro-mirror device.

[0012] The lens portion may include an objective lens arranged adjacent to the object.

[0013] The lens portion may include a tube lens located on the opposite side of the object relative to the objective lens.

[0014] It may further include a camera that captures the above object to generate a video image.

[0015] It may further include a computer that receives the image from the camera and determines the repair area of ​​the object.

[0016] A laser repair method according to one embodiment is a laser repair method for repairing defects in an object, wherein a laser beam generating unit emits a laser beam, a beam expander receives the laser beam and emits a laser beam with an expanded cross-sectional area, a digital micro-mirror device including a plurality of micro-mirrors receives the laser beam emitted from the beam expander, disperses the laser beam to emit multiple beams, an optical element receives the multiple beams, converges them, and irradiates the object, wherein the cross-section of the laser beam incident on the digital micro-mirror device covers the entire area of ​​the plurality of micro-mirrors.

[0017] The laser beam emitted from the above laser beam generating unit may include a plurality of wavelengths.

[0018] It may further include blocking some of the wavelengths among the plurality of wavelengths included in the laser beam emitted from the laser beam generator by using a filter located between the laser beam generator and the beam expander.

[0019] The cross-sectional area of ​​the laser beam incident on the digital micro-mirror device may have a size ranging from 2 to 16 times the total area of ​​the plurality of micro-mirrors.

[0020] The cross-section of the laser beam incident on the digital micro-mirror device includes a center and an outer portion surrounding the center, and an aperture located between the beam expander and the digital micro-mirror device can block the outer portion of the laser beam incident on the digital micro-mirror device.

[0021] The above aperture can reduce the cross-sectional area of ​​the laser beam incident on the digital micro-mirror device by 50% to 80%.

[0022] The intensity of the above center may be 86.5% or more of the maximum intensity of the laser beam incident on the digital micro-mirror device.

[0023] It may further include photographing the above object using a camera and generating a video image.

[0024] It may further include the computer determining the repair area of ​​the object using the above video image. Effects of the invention

[0025] According to the embodiments, the lifespan of a digital micro-mirror device included in a laser repair device or used in a laser repair method can be improved.

[0026] In addition, according to the embodiments, there are advantageous effects that can be recognized throughout the specification. Brief explanation of the drawing

[0027] FIG. 1 is a schematic diagram showing the components of a laser repair device according to one embodiment. Figure 2 is a video image of an object and a photograph showing the repair area. Figure 3 is a schematic illustration of a digital micro-mirror device that emits an incident laser beam as multiple beams. Figure 4 is a photograph showing the object after the repair is completed. Figure 5 is a schematic perspective view of a digital micro-mirror device. Figure 6 is an enlarged view showing the VI area of ​​Figure 5. Figure 7 is a photograph showing a damaged micro-mirror. Figure 8 is a diagram showing high-magnification and low-magnification images displayed on a digital micro-mirror device. Figure 9 is a drawing showing a low-magnification image. Figure 10 is a drawing showing a high-magnification image. FIG. 11 is a diagram showing the shape of a laser beam emitted from a beam expander of a laser repair device according to one embodiment and incident on a digital micro-mirror device. Figure 12 is a diagram showing the shape of a laser beam with a relatively wide cross-section emitted from a beam expander being incident on a digital micro-mirror device. Figure 13 is a diagram showing the shape of a laser beam emitted from a beam expander passing through an aperture and incident on a digital micro-mirror device. Figure 14 is a diagram showing the spatial distribution and profile of a laser beam emitted from a laser beam generator. Figure 15 is a diagram showing the spatial distribution and profile of a laser beam emitted from a beam expander. Figure 16 is a diagram showing the spatial distribution and profile of a laser beam passing through an aperture. Specific details for implementing the invention

[0028] Hereinafter, various embodiments of the present disclosure are described in detail with reference to the attached drawings so that those skilled in the art can easily implement them. The present disclosure may be embodied in various different forms and is not limited to the embodiments described herein.

[0029] To clearly explain the present disclosure, parts unrelated to the description have been omitted, and the same reference numerals are used for identical or similar components throughout the specification.

[0030] Furthermore, the size and thickness of each component shown in the drawings are depicted arbitrarily for convenience of explanation, and thus the present disclosure is not necessarily limited to what is illustrated. Thicknesses have been enlarged in the drawings to clearly represent various layers and regions. Additionally, in the drawings, the thickness of some layers and regions has been exaggerated for convenience of explanation.

[0031] Furthermore, when it is said that a part, such as a layer, membrane, region, or plate, is "on" or "on" another part, this includes not only the case where it is "directly above" the other part, but also the case where there is another part in between. Conversely, when it is said that a part is "directly above" another part, it means that there is no other part in between. Also, saying that a part is "on" or "on" a reference part means that it is located above or below the reference part, and does not necessarily mean that it is located "on" or "on" in the direction opposite to gravity.

[0032] Furthermore, throughout the specification, when a part is described as "including" a certain component, this means that, unless specifically stated otherwise, it does not exclude other components but may include additional components.

[0033] Additionally, throughout the specification, "planar" means when the subject part is viewed from above, and "cross-sectional" means when the cross-section obtained by vertically cutting the subject part is viewed from the side.

[0034] A laser repair device is a device capable of repairing defects in an object by generating a laser beam and altering the beam's propagation path to irradiate the object with a laser. For example, the object may be a display panel, which is one of the components of a display device. The display panel may be a device capable of displaying an image by including a plurality of pixels and a plurality of signal lines. The display panel may include a substrate and a plurality of thin film layers stacked on the substrate.

[0035] A display panel can be manufactured by depositing multiple thin film layers on a substrate. The thin film layers may include wiring patterns. In a display panel, the wiring patterns can serve to transmit electrical signals and power to each pixel.

[0036] Defects in the wiring pattern may occur due to contamination or process errors during the display panel manufacturing process. For example, defects in the wiring pattern may include open circuits, where the wiring is broken and no electricity flows, or short circuits, where wiring that should be separated is connected and unwanted electrical contact occurs.

[0037] The reliability of wiring patterns can directly affect the performance and image quality of display panels. If there are defects in the wiring patterns, the transmission of electrical signals is obstructed, which can cause problems with screen display. This can lead to a degradation of product quality. Therefore, to ensure product reliability and performance, it may be necessary to accurately detect and repair defects in the wiring patterns.

[0038] When a wiring pattern is formed by depositing a thin film layer on a substrate, the presence or absence of defects in the wiring pattern can be determined. The presence or absence of defects in the wiring pattern can be determined through an automated optical inspection (AOI) system. If a defect is detected by the automated optical inspection, the defect can be repaired by a laser repair device.

[0039] Below, with reference to FIG. 1, we will examine in detail a laser repair device capable of repairing defects in objects such as display panels. The objects that the laser repair device can repair are not limited to display panels.

[0040] FIG. 1 is a schematic diagram showing the components of a laser repair device according to one embodiment.

[0041] The laser repair device (10) may include a laser beam generator (100), a filter (200), a beam expander (300), an aperture (400), a digital micro-mirror device (500), a lens unit (600), a camera (700), a computer (800), a reflective mirror (RM), and a semi-transparent mirror (HM).

[0042] A laser beam generator (100) can generate and emit a laser beam (LI). The laser beam generator (100) may include a gain medium, a resonator, and a pumping system. The laser beam may be high-intensity light formed by amplifying light generated in the gain medium through a resonator. The laser beam (LI) emitted from the laser beam generator (100) may include multiple wavelengths. For example, the laser beam (LI) emitted from the laser beam generator (100) may include wavelengths of 355 nm, 532 nm, and 1064 nm.

[0043] The beam expander (300) can expand the diameter of the incident laser beam (LI) and emit it. The beam expander (300) can receive the laser beam (LI) emitted from the laser beam generator (100) and emit a laser beam (LI) with an expanded cross-sectional area. For example, the beam expander (300) may be composed of two or more lenses and a driving motor. The driving motor can expand the cross-sectional area of ​​the laser beam (LI) by adjusting the spacing between the lenses of the beam expander (300). Additionally, the beam expander (300) has the function of expanding the cross-sectional area of ​​the laser beam (LI), and the shape or structure of the beam expander (300) is not limited.

[0044] The filter (200) may be an optical element that selectively passes or blocks specific properties of the laser beam (LI). The filter (200) may block some of the wavelengths among the plurality of wavelengths included in the laser beam (LI) emitted from the laser beam generator (100). The filter (200) may be a band-pass filter. The filter (200) may be located between the laser beam generator (100) and the beam expander (300).

[0045] The aperture (400) is an optical element capable of limiting the cross-sectional area of ​​the laser beam (LI). The aperture (400) can block a portion of the cross-section of the laser beam (LI). The aperture (400) can be located between the beam expander (300) and the digital micro-mirror device (500). The cross-section of the laser beam (LI) incident on the digital micro-mirror device (500) may include a center and an outer portion surrounding the center. The aperture (400) can block the outer portion of the laser beam (LI) incident on the digital micro-mirror device (500).

[0046] The digital micro-mirror device (500) can disperse a laser beam (LI) to emit multiple beams (DL). The digital micro-mirror device (500) may include a plurality of micro-mirrors that receive a laser beam (LI) emitted from a beam expander (300), disperse it into multiple beams (DL), and emit them. The multiple beams (DL) may have a shape in which the laser beam (LI) is split into several parts. The cross-sectional shape of the multiple beams (DL) may be determined based on information regarding the repair area (RA) transmitted from the computer (800).

[0047] The lens unit (600) can receive multiple beams (DL) emitted from the digital micro-mirror device (500). The multiple beams (DL) incident on the lens unit (600) can converge and be irradiated onto an object (TO). Convergence of the multiple beams (DL) may mean that the multiple beams (DL) are reduced in size while maintaining their shape.

[0048] Additionally, the lens unit (600) can transmit reflected light (RL) reflected from the object (TO) to the camera (700). The reflected light (RL) transmitted to the camera (700) after passing through the lens unit (600) can be used by the camera (700) to generate an image (VDI) of the object (TO).

[0049] The lens portion (600) may include a tube lens (601) and an objective lens (602). The objective lens (602) of the lens portion (600) may be arranged adjacent to the object (TO). The tube lens (601) may be located on the opposite side of the object (TO) relative to the objective lens (602).

[0050] The magnification of the lens unit (600) can be adjusted. When the lens unit (600) has a high magnification, the size of the multiple beam (DL) irradiated onto the object (TO) is reduced further, and the image (VDI) of the object (TO) captured by the camera (700) can be magnified further. When the lens unit (600) has a low magnification, the size of the multiple beam (DL) irradiated onto the object (TO) is reduced less, and the image (VDI) of the object (TO) captured by the camera (700) can be magnified less.

[0051] The camera (700) can photograph the object (TO) to generate a video image (VDI) of the object (TO). The camera (700) can photograph the object (TO) using reflected light (RL) reflected from the object (TO). The reflected light (RL) may be light emitted from a light source provided to check for defects in the object (TO) that is reflected from the object (TO). The condition of the object (TO) can be checked using the video image (VDI) of the object (TO) captured by the camera (700).

[0052] The computer (800) can receive a video image (VDI) of the object (TO) captured by the camera (700) and determine the repair area (RA) of the object (TO). The repair area (RA) may be a specific area where a laser beam (LI) must be irradiated to repair a defect in the object (TO). The computer (800) can transmit information about the repair area (RA) to the digital micro-mirror device (500). Based on the received information about the repair area (RA), the digital micro-mirror device (500) can adjust the angle of each micro-mirror to generate a multi-beam (DL) of a shape corresponding to the repair area (RA).

[0053] A reflective mirror (RM) can change the path of a laser beam (LI) by reflecting it. The surface of the reflective mirror (RM) is coated to have high reflectivity, thereby minimizing the loss of the laser beam (LI). A laser repair device (10) can precisely control the path of the laser beam (LI) by using multiple reflective mirrors (RM). A semi-transparent mirror (HM) can transmit a portion of the laser beam (LI) and reflect reflected light (RL) reflected from an object (TO).

[0054] Hereinafter, the process of a laser repair device repairing a defect in an object will be described in detail with reference to FIGS. 2 to 4. FIG. 2 is a photograph showing an image of an object and a repair area. FIG. 3 is a photograph schematically illustrating a digital micro-mirror device that emits an incident laser beam as multiple beams. FIG. 4 is a photograph showing an object after the repair is completed.

[0055] A camera can capture an object to generate a visual image (VDI). The visual image (VDI) may include a wiring pattern of a thin film layer. The camera can transmit the visual image (VDI) to a computer. The computer can analyze the visual image (VDI) to distinguish the wiring pattern from other parts. Additionally, the computer can compare the captured wiring pattern with previously stored wiring patterns. By doing so, the computer can determine a repair area (RA) for repairing defects in the wiring pattern. The left illustration in FIG. 2 is an example of a visual image (VDI), and the right illustration may be an example of a repair area (RA).

[0056] The computer can convert information about the repair area (RA) into a digital signal and transmit it to the digital micro-mirror device (500). The digital micro-mirror device (500) can emit multiple beams by adjusting the angle of each micro-mirror using the received information about the repair area (RA). The shape of the multiple beams can correspond to the shape of the repair area (RA). FIG. 3 may be an example in which a laser beam (LI) is incident on the digital micro-mirror device (500) and emitted as multiple beams (DL) having a shape corresponding to the shape of the repair area (RA).

[0057] Multiple beams emitted from a digital micro-mirror device can converge as they pass through a lens section and be reduced to a size suitable for correcting defects in the wiring pattern. Defects in the wiring pattern can be repaired by laser irradiation. Fig. 4 may be an example of an image (VDI') of an object after repair is completed.

[0058] Below, the digital micro-mirror device will be examined in detail with reference to FIGS. 5 and FIGS. 6. FIGS. 5 is a schematic perspective view of the digital micro-mirror device. FIGS. 6 is an enlarged view showing the VI area of ​​FIGS. 5.

[0059] The digital micro-mirror device (500) may include a plurality of micro-mirrors (501). The digital micro-mirror device (500) may selectively irradiate a laser beam received from a beam expander onto an object as multiple beams.

[0060] The angle of each micro-mirror (501) can be adjusted according to information regarding the repair area. By changing the angle of each micro-mirror (501), the direction in which light reflected from each micro-mirror (501) is emitted can be controlled. For example, a digital micro-mirror device (500) may have a plurality of micro-mirrors (501) arranged in a grid shape on a static RAM cell. The micro-mirrors (501) included in a single digital micro-mirror device (500) may form a matrix of, for example, 1920×1080. A high-reflectivity material such as aluminum may be deposited on the surface of the micro-mirrors (501).

[0061] When information regarding the repair area is recorded in the static RAM cell of the digital micro-mirror device (500), the tilt angle of the micro-mirror (501) can be determined according to the recorded information. The micro-mirror (501) can be tilted at a° or -a°. For example, the micro-mirror (501) can be tilted at 12° or -12°, but is not limited thereto. When the micro-mirror (501) is tilted at a°, it can be called the ON state of the micro-mirror (501), and when the micro-mirror (501) is tilted at -a°, it can be called the OFF state of the micro-mirror (501). Or, it may be set in the opposite way. When the micro-mirror (501) is in the ON state, a laser beam can be irradiated onto an object, and when the micro-mirror (501) is in the OFF state, a laser beam may not be irradiated onto an object.

[0062] Whether each micro mirror (501) is turned on or off may vary depending on the shape of the repair area. That is, a group of micro mirrors (501) inclined at a° may correspond to the shape of the repair area.

[0063] Below, with reference to Fig. 7, we will examine in detail the relationship between damage to the micro-mirror and the lifespan of the digital micro-mirror device. Fig. 7 is a photograph showing a damaged micro-mirror.

[0064] The micro-mirror (501) can be damaged by the incident laser beam. In particular, the greater the intensity of the incident laser beam, the more severe the damage to the micro-mirror (501) can be. Damage to the micro-mirror (501) can interfere with the precise control and direction adjustment of the laser beam, thereby reducing the precision of the repair work. As a result, defects in the wiring pattern may not be properly repaired or additional damage may occur. Ultimately, damage to the micro-mirror (501) can shorten the lifespan of the digital micro-mirror device (500) and degrade the overall performance of the digital micro-mirror device (500).

[0065] Hereinafter, with reference to FIGS. 8 to 10, the micro-mirror that is turned on will be specifically described by comparing the case where the lens part is at high magnification and the case where it is at low magnification. FIG. 8 is a drawing showing a high-magnification image and a low-magnification image expressed in a digital micro-mirror device. FIG. 9 is a drawing showing a low-magnification image. FIG. 10 is a drawing showing a high-magnification image.

[0066] When a high-magnification lens is used in a laser repair device, the camera can generate a more magnified image. Since the defect is also magnified, the computer can determine the repair area more precisely using the magnified image. The repair area determined more precisely can be a high-resolution repair area.

[0067] Since the high-magnification lens portion converges multiple beams further, a high-magnification image can be formed in the digital micro-mirror device (500).

[0068] When a low-magnification lens is used in a laser repair device, the camera may generate a less magnified image. Since the defect is also less magnified, the computer can determine the repair area less precisely using the less magnified image. The repair area determined less precisely may be a low-resolution repair area.

[0069] Since the low-magnification lens portion converges the multiple beams less, a low-magnification image can be formed in the digital micro-mirror device (500).

[0070] When considering the case where the same object is photographed using a camera, the high-magnification image (HMI) may have the same shape as the low-magnification image (LMI) but be larger in size. Ultimately, the number of micro-mirrors (501) that are turned on in the digital micro-mirror device (500) can be determined by the magnification of the lens part.

[0071] The low-magnification image (LMI) of FIG. 9 emits multiple beams with three micro-mirrors (501) turned on, and the high-magnification image (HMI) of FIG. 10 emits multiple beams with 12 micro-mirrors (501) turned on. The shape and size of the multiple beams formed by the high-magnification image (HMI) and the low-magnification image (LMI) may have the same characteristics when irradiated onto an object. However, the high-magnification image (HMI) can form a larger number of multiple beams than the low-magnification image (LMI), which may enable more precise repair work on the object.

[0072] Below, with reference to FIGS. 11 to 13, we will specifically examine a laser repair device according to one embodiment that can improve the lifespan of a digital micro-mirror device.

[0073] FIG. 11 is a diagram showing the shape of a laser beam emitted from a beam expander of a laser repair device according to one embodiment and incident on a digital micro-mirror device.

[0074] The cross-section (CS) of the laser beam (LI) incident on the digital micro-mirror device (500) can cover the entire digital micro-mirror device (500). Additionally, the cross-section (CS) of the laser beam (LI) incident on the digital micro-mirror device (500) can have a size that covers the entire area of ​​the plurality of micro-mirrors. The entire area of ​​the plurality of micro-mirrors may be an area that includes the reflection area of ​​all micro-mirrors. This allows for the lifespan of the digital micro-mirror device (500) to be improved while reducing damage to the micro-mirrors.

[0075] As the laser beam (LI) passes through the beam expander (300), it is expanded and incident on the digital micro-mirror device (500). The cross-section (CS) of the expanded laser beam (LI) can cover the entire area of ​​the digital micro-mirror device (500). When the laser beam (LI) is expanded over a wide area, the intensity of the laser beam (LI) reaching each micro-mirror can be dispersed and reduced. The laser beam (LI) with reduced intensity can reduce damage to the micro-mirrors. This can improve the lifespan and performance of the digital micro-mirror device (500).

[0076] Conversely, if a laser beam is focused and irradiated onto only some of the micromirrors in a digital micromirror device, a very high-intensity laser beam may be delivered to that area. Such a focused laser beam can deliver excessive energy to the micromirrors in that region. This excessive energy can cause surface damage to the micromirrors. Over time, this damage can become increasingly severe, and damaged micromirrors can make precise control of the laser beam difficult. Consequently, the lifespan and performance of the digital micromirror device may be degraded.

[0077] That is, by making the range of the laser beam (LI) incident on the digital micro-mirror device (500) large enough to cover the entire area of ​​the digital micro-mirror device (500), damage to the micro-mirror can be reduced and the lifespan of the digital micro-mirror device (500) can be improved. In addition, the maintenance cycle for the digital micro-mirror device (500) can be extended and the replacement cost can be reduced.

[0078] Figure 12 is a diagram showing the shape of a laser beam emitted from a beam expander and incident on a digital micro-mirror device, having a wider cross-section compared to Figure 11.

[0079] The cross-sectional area of ​​the laser beam (LI) emitted from the beam expander (300) and incident on the digital micro-mirror device (500) may not be limited. For example, the cross-sectional area of ​​the laser beam (LI) incident on the digital micro-mirror device (500) may have a size ranging from 2 to 16 times the total area of ​​the plurality of micro-mirrors. Alternatively, the cross-sectional area of ​​the laser beam (LI) incident on the digital micro-mirror device (500) may have a size ranging from 4 to 9 times the total area of ​​the plurality of micro-mirrors.

[0080] If the cross-sectional area of ​​the digital micro-mirror device (500) is further expanded, the intensity of the laser beam (LI) incident on the entire area of ​​the plurality of micro-mirrors can be minimized. Therefore, it may be advantageous for improving the lifespan of the digital micro-mirror device (500).

[0081] Figure 13 is a diagram showing the process in which a laser beam emitted from a beam expander passes through an aperture and is incident on a digital micro-mirror device.

[0082] The cross-section of the laser beam (LI) may include a center (CR) and an outer region (ER). The outer region (ER) may be an area surrounding the center (CR). In the cross-section of the laser beam (LI), the outer region (ER) may be an area blocked by the aperture (400). In the cross-section of the laser beam (LI), the center (CR) may be an area that passes through the aperture (400) and is incident on the digital micro-mirror device (500). For example, the intensity of the laser beam (LI) in the center (CR) may be 86.5% or more of the maximum intensity of the laser beam (LI) incident on the digital micro-mirror device (500). The outer region (ER) may be a portion where the intensity of the laser beam (LI) is less than 86.5% of the maximum intensity of the laser beam (LI).

[0083] The cross-section (CS) of the laser beam (LI) incident on the digital micro-mirror device (500) may consist only of the region corresponding to the center (CR). The region corresponding to the outer part (ER) may be blocked by the aperture (400). The aperture (400) may reduce the cross-sectional area of ​​the laser beam (LI) incident on the digital micro-mirror device (500). For example, the aperture (400) may be configured to reduce the cross-sectional area of ​​the laser beam (LI) incident on the digital micro-mirror device (500) by 50% to 80%.

[0084] A laser beam (LI) may exhibit a cross-sectional intensity distribution that is highest at the center and gradually decreases as it moves away from the center. This intensity distribution may follow a Gaussian distribution.

[0085] In addition, the difference in intensity depending on the position of the cross-section of the laser beam (LI) can be minimized at the center (CR). Therefore, if the entire area of ​​the multiple micro-mirrors is covered with the region corresponding to the center (CR), uniform damage can be inflicted on the micro-mirrors. Since damage can be prevented from being concentrated on specific micro-mirrors, the lifespan of the digital micro-mirror device (500) can be improved by placing an aperture (400) that blocks the outer edge (ER) of the laser beam (LI).

[0086] Below, the relationship between the cross-sectional position and intensity of the laser beam will be examined in detail with reference to FIGS. 14 to 16. FIG. 14 is a diagram showing the spatial distribution and profile of a laser beam emitted from a laser beam generator. FIG. 15 is a diagram showing the spatial distribution and profile of a laser beam emitted from a beam expander.

[0087] The laser beam (LI) passing through the beam expander can have its cross-sectional area expanded while maintaining Gaussian distribution characteristics. Comparing FIG. 14 and FIG. 15, it can be seen that the spatial distribution of the laser beam (LI) becomes wider when passing through the beam expander (300).

[0088] As the cross-section of the laser beam (LI) expands, changes in intensity may occur in the laser beam (LI). Fig. 14 shows a high-intensity laser beam (LI) concentrated in a narrow area. Fig. 15 shows that as the same energy is dispersed over a wider area, the maximum intensity may decrease relatively. This may be a natural phenomenon due to the law of conservation of energy.

[0089] Figure 16 is a diagram showing the spatial distribution and profile of a laser beam passing through an aperture.

[0090] FIG. 16 illustrates the process of controlling the intensity distribution of a laser beam (LI) using an aperture (400).

[0091] The aperture (400) can selectively separate the center (CR) and the outer portion (ER) of the laser beam (LI). The aperture (400) can block the outer portion (ER) of the cross-section of the laser beam (LI) and allow only the center (CR) to be incident on the digital micro-mirror device.

[0092] By using an aperture (400) so that the cross-section of the laser beam (LI) incident on the digital micro-mirror device covers the entire area of ​​the plurality of micro-mirrors, a uniform and low-intensity laser beam (LI) can be irradiated onto all micro-mirrors. This can improve the lifespan of the digital micro-mirror device (500).

[0093] Although embodiments of the present disclosure have been described in detail above, the scope of the present disclosure is not limited thereto, and various modifications and improvements by those skilled in the art using the basic concepts of the present disclosure as defined in the following claims also fall within the scope of the present disclosure. Explanation of the symbols

[0094] 10: Laser repair device 100: Laser beam generator 200: Filter 300: Beam Expander 400: Aperture 500: Digital micro-mirror device 501: Micro-mirror 600: Lens part 601: Tube lens 602: Objective lens 700: Camera 800: Computer TO: Object LI: Laser beam DL: Multibeam RL: Reflected light VDI, VDI': Video Image RA: Repair area CS: Section CR: Center ER: Outer area HMI: High-magnification image LMI: Low magnification image

Claims

Claim 1 A laser repair device for repairing defects in an object, comprising: a laser beam generating unit that emits a laser beam; a beam expander that receives the laser beam and emits a laser beam with an expanded cross-sectional area; a digital micro-mirror device including a plurality of micro-mirrors that receive the laser beam emitted from the beam expander and disperse it into multiple beams; and a lens unit that receives the multiple beams, converges them, and irradiates them onto the object, wherein the cross-section of the laser beam incident on the digital micro-mirror device has a size capable of covering the entire area of ​​the plurality of micro-mirrors. Claim 2 A laser repair device according to claim 1, wherein the laser beam emitted from the laser beam generating unit comprises a plurality of wavelengths. Claim 3 A laser repair device according to claim 2, further comprising a filter positioned between the laser beam generator and the beam expander, which blocks some of the plurality of wavelengths included in the laser beam emitted from the laser beam generator. Claim 4 A laser repair device according to claim 1, wherein the cross-sectional area of ​​the laser beam incident on the digital micro-mirror device has a size ranging from 2 to 16 times the total area of ​​the plurality of micro-mirrors. Claim 5 A laser repair device according to claim 1, wherein the cross-section of the laser beam incident on the digital micro-mirror device comprises a center and an outer portion surrounding the center, and further comprises an aperture located between the beam expander and the digital micro-mirror device and blocking the outer portion of the laser beam incident on the digital micro-mirror device. Claim 6 A laser repair device according to claim 5, wherein the aperture is configured to reduce the cross-sectional area of ​​the laser beam incident on the digital micro-mirror device by 50% to 80%. Claim 7 A laser repair device according to claim 5, wherein the intensity of the central portion is 86.5% or more of the maximum intensity of the laser beam incident on the digital micro-mirror device. Claim 8 A laser repair device according to claim 1, wherein the lens portion comprises an objective lens arranged adjacent to the object. Claim 9 A laser repair device according to claim 8, wherein the lens portion comprises a tube lens located on the opposite side of the object with respect to the objective lens. Claim 10 A laser repair device according to claim 1, further comprising a camera that photographs the object to generate an image. Claim 11 A laser repair device according to claim 10, further comprising a computer that receives the image from the camera and determines the repair area of ​​the object. Claim 12 A laser repair method for repairing defects in an object, wherein a laser beam generating unit emits a laser beam, a beam expander receives the laser beam and emits a laser beam with an expanded cross-sectional area, a digital micro-mirror device including a plurality of micro-mirrors receives the laser beam emitted from the beam expander, disperses the laser beam to emit multiple beams, a lens unit receives the multiple beams, converges them, and irradiates the object, wherein the cross-sectional area of ​​the laser beam incident on the digital micro-mirror device covers the entire area of ​​the plurality of micro-mirrors. Claim 13 A laser repair method according to claim 12, wherein the laser beam emitted from the laser beam generating unit comprises a plurality of wavelengths. Claim 14 A laser repair method according to claim 13, further comprising blocking some of the plurality of wavelengths included in the laser beam emitted from the laser beam generator using a filter located between the laser beam generator and the beam expander. Claim 15 A laser repair method according to claim 12, wherein the cross-sectional area of ​​the laser beam incident on the digital micro-mirror device has a size ranging from 2 to 16 times the total area of ​​the plurality of micro-mirrors. Claim 16 A laser repair method according to claim 12, wherein the cross-section of the laser beam incident on the digital micro-mirror device comprises a center and an outer portion surrounding the center, and an aperture located between the beam expander and the digital micro-mirror device blocks the outer portion of the laser beam incident on the digital micro-mirror device. Claim 17 A laser repair method according to claim 16, wherein the aperture reduces the cross-sectional area of ​​the laser beam incident on the digital micro-mirror device by 50% to 80%. Claim 18 A laser repair method according to claim 16, wherein the intensity of the center is 86.5% or more of the maximum intensity of the laser beam incident on the digital micro-mirror device. Claim 19 A laser repair method according to claim 12, further comprising photographing the object using a camera and generating a video image. Claim 20 A laser repair method according to claim 19, further comprising a computer determining a repair area of ​​the object using the above-described image.

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