KR20090068945A - Method and apparatus for inspecting edge-side of glass plate, and method for manufacturing flat display panel - Google Patents

Abstract

A method and a device for inspecting an edge surface of a glass substrate and a manufacturing method of a flat display panel are provided to detect defects such as chipping, edge loss or a non-grinded portion occurring in the edge surface through a laser beam and a photo sensor. A transferred glass substrate is arranged by a stage(S101). A laser emitting unit applies a laser beam to an edge surface of the glass substrate(S201). A photo sensor receives the laser beam reflected from the edge surface of the glass substrate(S301). A controller detects the amount of light of laser beams collected by the photo sensor(S401).

Description

METHOD AND APPARATUS FOR INSPECTING EDGE-SIDE OF GLASS PLATE, AND METHOD FOR MANUFACTURING FLAT DISPLAY PANEL

The present invention provides a method and apparatus for inspecting edges of glass substrates and flat panel displays, which can improve the detection accuracy of defects such as chipping, edge defects, and non-abrasive parts generated on the edges of glass substrates through a simple configuration. It relates to a manufacturing method.

In general, a flat panel display panel (FDP) is classified into a device using an inorganic material and a device using an organic material based on the material used. Devices using inorganic materials include plasma display panels (PDPs) using PL (photo luminescence) and field emission displays (FEDs) using CE (Cathode Luminescence), and organic materials. Examples of the device to be used include a liquid crystal display (LCD) and an organic light emitting display (OLED).

In the production process of such a flat panel display panel, first, the plate glass manufactured to a predetermined thickness (about 0.5 to 2.8 mm) is cut to fit the size of the panel to be produced, and then minute unevenness is formed on the edge surface of the cut glass substrate. In order to remove the undulation, it is commercialized by grinding. However, even after polishing the edge surface of the glass substrate, defects such as chipping, edge defects or non-polishing portions may exist.

FIG. 1 is a perspective view illustrating a defect generated in a general glass substrate, and the defect generated in the glass substrate 10 includes a chipping 11, an edge defect 12, or a non-abrasive portion 13.

The chipping 11 and the edge defect 12 are defects that occur when a part of the edge surface is removed by grinding or an external impact such as grinding, and the edge defect 12 is compared with the chipping 11. It is relatively large. On the contrary, the non-abrasive portion 13 is a defect caused by not being polished due to wear of a grinder such as a grinder.

If the manufacturing process of the flat panel display panel is continued while overlooking the above defects, an error may occur during the transfer or alignment of the glass substrate, and the particles generated during the production process may be disposed on the production line as well as the glass substrate. Various devices may cause serious problems. In addition, even when the fabrication of the flat panel display device is completed, stress concentration may be generated around the above-mentioned defects even in a small external shock, and thus the panel may be easily damaged.

Therefore, it is possible to inspect the edges of glass substrates that can inspect the edges of glass substrates to determine the presence of defects and to prevent unnecessary work in the following processes, thereby increasing the production efficiency and maintaining the high reliability and quality of the glass substrates. Skill is needed.

FIG. 2 is a schematic diagram illustrating the light reflection and the light absorption of the glass substrate 10. The light reflection reflects the reflected light I2 at an angle equal to the incident angle θ when the incident incident light I1 meets the interface. Say something.

Contrary to the light reflection, the light intensity of the reflected light I2 reflected from the interface is lower than that of the incident light I1, and the absorption of part of the incident light I1 into the interface is called light absorption.

Background Art [0002] Conventional methods and devices for inspecting edges of glass substrates include methods and apparatuses for detecting defects in glass substrates after imaging with a camera by transmitting or reflecting a light source such as an LED onto a glass substrate. However, as described above, the intensity of the reflected light I2 transmitted or reflected from the edge surface 15 of the glass substrate 10 is weak, so that the detection accuracy of defects generated on the edge surface 15 of the glass substrate 10 is inferior. There is a problem with the size and complexity of the device for the installation of LEDs and cameras.

The method and apparatus for inspecting edges of a glass substrate according to the prior art have a problem in that the apparatus is enlarged by using a method of photographing light transmitted or reflected from the glass substrate with a camera using an LED as a light source.

In addition, the detection accuracy is low, there is a problem in that it is not easy to determine the fine defects, as well as using expensive equipment.

An object of the present invention devised to solve the above problems, glass that can increase the detection accuracy for defects such as scratches and non-abrasive parts such as chipping, edge defects, etc. generated on the edge surface of the glass substrate through a simple configuration The present invention provides a method and apparatus for inspecting an edge of a substrate and a method for manufacturing a flat panel display panel.

In order to achieve the above object, an edge surface inspection method of a glass substrate according to the present invention includes a glass substrate alignment step of supporting and aligning the transferred glass substrate, and laser beam irradiation for irradiating a laser beam to the edge surface of the glass substrate. And a laser beam receiving step of receiving the laser beam reflected from the edge surface of the glass substrate with a photosensor, and a light amount detecting step of detecting the light quantity of the received laser beam.

In addition, a light amount determination step performed after the light amount detection step and determining whether the detected light amount of the laser beam is within a range of a predetermined light amount, and alerting the outside when the light amount is out of a range of a predetermined light amount. It further comprises a warning step.

The glass substrate alignment step includes a glass substrate photographing step of photographing the glass substrate and a glass substrate correction step of measuring the degree of alignment of the photographed glass substrate and correcting the glass substrate to be aligned within a range of a preset alignment value. And a glass substrate fixing step of fixing the corrected glass substrate.

The laser beam irradiation step may include a laser beam emission step of generating and amplifying a laser beam to emit a laser beam from a laser light emitting unit, and an edge surface for guiding the emitted laser beam to the edge surface of the glass substrate. Characterized in that it comprises a guide step.

The laser beam receiving step may include a laser beam condensing step of condensing a laser beam reflected from an edge surface of the glass substrate using a condenser lens, and a photo for guiding the laser beam condensed by the condenser lens to a photo sensor. It characterized in that it comprises a sensor guide step.

On the other hand, the edge surface inspection apparatus of the glass substrate according to the present invention includes a stage for supporting and aligning the transferred glass substrate, a laser beam irradiation unit for irradiating a laser beam to the edge surface of the glass substrate, the edge of the glass substrate A laser beam receiving unit for receiving a laser beam reflected from the surface, and a control unit for receiving a signal from the laser beam receiving unit and detecting the amount of light of the laser beam to determine whether it is within a predetermined range of light amount.

The apparatus may further include a warning unit which warns and notifies the outside when the amount of light determined by the controller is outside the range of a preset amount of light.

In addition, the laser beam irradiation unit includes a laser light emitting unit for generating and amplifying a laser beam and a first guide means for guiding the laser beam irradiated from the laser light emitting unit to an edge surface of the glass substrate. It is characterized by.

The laser beam light receiving unit may include a condenser lens for condensing the laser beam reflected from the edge surface of the glass substrate, and a photosensor for receiving the laser beam condensed from the condenser lens.

The laser beam receiving unit may further include second guide means for guiding the laser beam collected from the condenser lens to the photosensor.

On the other hand, in the manufacturing method of the flat panel display panel according to the present invention, the glass substrate is manufactured by cutting each glass substrate according to the size of the panel to produce a plate glass manufactured to a predetermined thickness after polishing the edge surface of the glass substrate A step, an edge test step of inspecting whether the polished glass substrate is defective or not, and the glass substrate judged to be good, half-assembled and bonded to a pair of upper and lower plates, and then injected with gas or liquid crystal In the method of manufacturing a flat panel display panel comprising a panel manufacturing step of completing a display panel, the edge surface inspection step, the glass substrate alignment step of supporting and aligning the transferred glass substrate, and the edge surface of the glass substrate A laser beam irradiation step of irradiating a laser beam, and receiving a laser beam reflected from an edge surface of the glass substrate with a photosensor The laser beam receiving step and the light amount detecting step for detecting the light amount of the laser beam received by the photosensor.

According to the present invention, the method and apparatus for inspecting the edge surface of a glass substrate can detect defects such as chipping, edge defects or non-abrasive portion generated on the edge surface of the glass substrate by a simple configuration using a laser beam and a photo sensor. The detection accuracy can be improved.

In addition, the user can easily know the glass substrate is a defect generated by the control unit and the warning unit can provide a high reliability and high quality glass substrate with the improvement of production efficiency.

In addition, since the laser light emitting unit and the photosensor can be easily installed at a desired position through the first and second guide means, the installation and accessibility of the device are good.

On the other hand, the manufacturing method of the flat panel display panel according to the present invention, it is possible to increase the detection accuracy of defects through the edge surface inspection method of the glass substrate to prevent the generation of particles in the production process to protect the glass substrate and various equipment Can improve the quality of the finished panel.

Hereinafter, with reference to the accompanying drawings will be described in detail a preferred embodiment of the method and apparatus for testing the edge surface of the glass substrate according to the present invention.

FIG. 3 is a block diagram showing a first embodiment of an edge inspection method of a glass substrate according to the present invention, and FIG. 4 is a block diagram showing a second embodiment of an edge inspection method of a glass substrate according to the present invention. 5 is a block diagram showing a third embodiment of the edge surface inspection method of the glass substrate according to the present invention, Figure 6 is a first embodiment of the edge surface inspection apparatus of the glass substrate according to the present invention. 7 is a configuration diagram showing a second embodiment of an edge surface inspection apparatus of a glass substrate according to the present invention.

According to the present invention, a method for inspecting an edge of a glass substrate includes a glass substrate alignment step (S101), a laser beam irradiation step (S201), a laser beam light receiving step (S301), and a light amount detecting step as illustrated in FIGS. 3 to 5. S410, and may further include a light amount determining step S501 and a warning step S601. In addition, the glass substrate alignment step (S101) may include a glass substrate photographing step (S121), a glass substrate correction step (S141) and a glass substrate fixing step (S161), the laser beam irradiation step (S201) The laser beam emitting step S221 and the edge surface guiding step S241 may be included, and the laser beam receiving step S301 may include a laser beam collecting step S321 and a photosensor guide step S341. .

On the other hand, the edge surface inspection apparatus of the glass substrate according to the present invention, the stage 100, the laser beam irradiation unit 200, the laser beam light receiving unit 300 and the control unit 400 as shown in FIGS. It is made to include, may further include a warning unit 500. The laser beam irradiation unit 200 may include a laser light emitting unit 220 and a first guide means 240. The laser beam light receiving unit 300 includes a condenser lens 320, a photo sensor 340, and It may include a second guide means 360.

The alignment step S101 supports and aligns the transferred glass substrate 10. The transferred glass substrate 10 refers to the glass substrate 10 in which the edge surface 15 is polished after cutting the large-area plate glass to the size of the panel. The glass substrate 10 is transferred to the stage 100 by a transfer unit (not shown). The alignment method of the glass substrate 10 is performed by the stage 100, and as shown in FIG. 4, the alignment step S101 includes a photographing step S121 of photographing the glass substrate 10 and the photographed above. A calibration step (S141) of measuring the alignment degree of the glass substrate 10 to correct the glass substrate 10 to be aligned within a preset alignment value (S141), and a fixing step of fixing the corrected glass substrate 10 ( S161) may be included. In this case, the stage 100 processes a camera photographing the glass substrate 10 and an image signal photographed from the camera to perform the photographing step S111, and measures the alignment degree of the glass substrate 10. The controller may be configured to determine whether it is within a range of a preset alignment value, and a driving unit connected to the controller to drive the stage to align the glass substrate 10 within a range of a preset alignment value. Here, the alignment key may be displayed on the glass substrate 10 photographed by the camera, and the alignment degree of the glass substrate 10 is measured through the alignment key. The control unit determines the alignment value of the measured glass substrate 10 and drives the driving unit to correct the glass substrate 10 to be aligned within a range of a preset alignment value, that is, within a range where no defect occurs. . As a result, the correction step S121 and the fixing step S131 are performed.

In the laser beam irradiation step S201, the laser beam is irradiated onto the edge surface 15 of the glass substrate 10. As shown in FIG. 5, the laser beam irradiation step S201 generates and amplifies a laser beam so that the laser beam is emitted from the laser light emitting unit 220 shown in FIG. It may include an edge guide step (S241) for guiding the laser beam to be irradiated to the edge surface 15 of the glass substrate 10.

In order to perform the laser beam irradiation step (S201), as shown in FIG. 6, the laser beam irradiation unit 200 irradiates a laser beam to the edge surface 15 of the aligned glass substrate 10. As shown in FIG. 7, the laser beam irradiation unit 200 generates and amplifies a laser beam to irradiate a laser beam, and a laser light emitting unit 320 irradiates the laser beam to the edge surface of the glass substrate 10. It may include a first guide means 240 to guide to (15). Since the laser light emitting unit 320 may be installed to irradiate a laser beam on the edge surface 15 of the glass substrate 10, any position may be used. However, when the laser light emitting unit 220 is positioned on the same plane as the glass substrate 10, the laser is not directly provided on the edge surface 15 of the glass substrate 10 without having to separately provide the first guide means 240. The beam can be irradiated. However, when the laser light emitting unit 220 is installed in the vertical direction with respect to the glass substrate 10 as shown in FIG. 7, the edge surface 15 of the glass substrate 10 is passed through the first guide means 240. ) Can be irradiated with a laser beam. Accordingly, the installation and accessibility of the inspection apparatus can be improved.

Edge guide step (S241) is performed by the first guide means 240, the first guide means 240 reflects the laser beam irradiated as shown in Figure 7 of the glass substrate 10 It may be a prism guiding the edge surface 15. In addition, the first guide means 240 may be a reflective glass or a reflective mirror, or may be a flexible optical fiber. That is, the first guide means 240 may be any configuration as long as the laser beam is irradiated to the edge surface 15 of the glass substrate 10 by guiding the laser beam emitted from the laser light emitting unit 220.

In the laser beam receiving step S301, the laser beam reflected from the edge surface 15 of the glass substrate 10 is received by the photosensor 340. As shown in FIG. 5, in the laser beam receiving step S301, a laser beam that collects a laser beam reflected from the edge surface 15 of the glass substrate 10 using the condensing lens 320 shown in FIG. 7. It may include a beam condensing step (S321), and a photosensor guide step (S341) for guiding the laser beam collected by the condensing lens 320 to the photosensor 340.

In order to perform the laser beam receiving step S301, as shown in FIG. 6, the laser beam receiving unit 200 receives the laser beam reflected from the edge surface 15 of the glass substrate 10. As shown in FIG. 7, the laser beam receiving unit 200 includes a condenser lens 320 for condensing a laser beam reflected from the edge surface 15 of the glass substrate 10, and a condenser lens 320. It may include a photosensor 340 for receiving the focused laser beam. The condenser lens 320 is provided with the same reflection angle as the incident angle of the laser beam irradiated to the edge surface 15 of the glass substrate 10 as the center point of the circle according to the light reflection condition shown in FIG. 2. The size of the condenser lens 320 is determined according to the degree of defects generated on the edge surface 15 of the glass substrate 10. That is, when the laser beam incident by the defect is diffusely reflected or scattered, the larger the condensing lens 320, the more the condensed laser beam can be focused. However, it is not necessary to judge the defect as a very fine defect. The range should be set in advance by experiment. Therefore, when the size of the condenser lens 320 is determined and there is a defect that is determined to be defective, the laser beam focused on the condenser lens 320 will be very minute.

The photosensor 340 may be any position as long as it can be installed to receive the laser beam focused from the condenser lens 320. However, when the photosensor 340 is positioned on the same line as a straight line from which the laser beam focused from the condenser lens 320 is emitted, it is not necessary to provide a second guide means 360 separately from the condenser lens 320. The focused laser beam can be focused. However, when the photosensor 220 is installed in the vertical direction with respect to the laser beam emitted from the condenser lens 320 as shown in FIG. 7, it is necessary to receive the laser beam via the second guide means 360.

As illustrated in FIG. 7, the second guide means 360 may be a prism for guiding the laser beam collected from the condenser lens 320 to the photosensor 340. 1 is the same as the guide means 240, so the detailed description thereof will be omitted.

In the light amount detecting step S401, the light amount of the received laser beam is detected. The detection of the amount of light changes the laser beam received by the photosensor 340 to the intensity of the current and transmits it to the controller 400 shown in FIG. 6, and based on the transmitted signal, The amount of light will be detected. Reflected light I2 reflected from the edge surface 15 of the glass substrate 10 according to the light absorption condition shown in FIG. 2 has a lower detection accuracy than the incident light I1, but uses a high energy laser beam. As a result, the detection accuracy can be increased, and the photosensor 340 can use a silicon photo transistor in consideration of photosensitivity and responsiveness.

The light amount determining step S501 is performed after the light amount detecting step S401, and determines whether the detected light amount of the laser beam is within a preset light amount range. Based on the signal transmitted from the photosensor 340 to the controller 400, the range of the current intensity according to the preset light amount is determined. In other words, if the edge surface 15 of the glass substrate 10 is defective or very fine, it should be judged as good. In this case, there will be many laser beams focused on the condensing lens 320, and since the amount of light is detected by the photosensor 340 for receiving the laser beam from the condensing lens 320, the intensity of the current transmitted to the controller 400 is also high. Will be. However, when it is necessary to determine a defect generated in the edge surface 15 of the glass substrate 10 as a defect, when the laser beam is irradiated to the edge surface 15 of the glass substrate 10, it is diffusely reflected or scattered by the defect and condensed. Less laser beam reflected by the lens 320 will be focused. Accordingly, the light amount of the laser beam received by the photosensor 340 is also reduced, the intensity of the current delivered to the controller 400 is also reduced. That is, the range of the predetermined light amount in the light amount determination step (S501) refers to a range that is determined to be good or bad according to the degree of the defect generated in the edge surface 15 of the glass substrate 10, which is The controller 400 determines whether it is within a range that is determined to be good through a range of current strength set in advance.

The warning step S601 warns the outside when the light amount is out of the range of the preset light amount. That is, when it is determined that the range of the light amount determined in the light amount determination step (S501) is bad, it is to warn the external user through the warning unit 500 shown in FIG. The warning unit 500 may be a speaker or a buzzer that notifies the outside through a warning sound, and may be visually transmitted to an external user through a warning light. In this case, the user observes the edge surface 15 of the glass substrate 10 judged to be defective by the warning unit 500, and if it can be made good by regrinding, re-grinding and overcoming the defects. If it is not possible, it will be necessary to discard the glass substrate 10 judged as defective.

8 is a block diagram showing a preferred embodiment of a method for manufacturing a flat panel display panel according to the present invention. Hereinafter, a preferred embodiment of the method for manufacturing a flat panel display panel according to the present invention will be described in detail with reference to FIG. 8. do.

The method for manufacturing a flat panel display panel according to the present invention includes a glass substrate manufacturing step (S11), an edge surface inspection step (S21) and a panel manufacturing step (S31), as shown in FIG. The inspection step S21 includes a glass substrate alignment step S101, a laser beam irradiation step S201, a laser beam receiving step S301, and a light amount detecting step S401.

Glass substrate manufacturing step (S11) is to cut the plate glass manufactured to a predetermined thickness (about 0.5 to 2.8mm) in accordance with the size of the panel to be produced to remove minute irregularities or undulations on the edge surface of the cut glass substrate It is polished to make it. Polishing of the edge surface of the glass substrate may be performed using equipment such as a grinder. However, even after polishing the edge surface of the glass substrate, defects such as chipping, edge defects or non-polishing portions may exist. In order to inspect the defects present in the edge surface of the glass substrate as described above, the edge surface inspection step (S21) is to be performed.

Edge test step (S21) is to check whether the edge of the polished glass substrate is defective. More specifically, the edge inspection step S21 includes a glass substrate alignment step S101 for supporting and aligning the transferred glass substrate, and a laser beam irradiation step S201 for irradiating a laser beam to the edge surface of the glass substrate. And a laser beam receiving step (S301) for receiving a laser beam reflected from the edge surface of the glass substrate with a photosensor, and a light amount detecting step (S401) for detecting the light amount of the laser beam received by the photosensor. It is done by

In the method of manufacturing a flat panel display panel according to the present invention, since the edge surface inspection step (S21) is the same as the edge surface inspection method of the glass substrate of the present invention, redundant description will be omitted.

In the panel manufacturing step S31, the glass substrate judged to be good through the edge inspection step S21 is semi-assembled and bonded to a pair of upper and lower plates, and then gas or liquid crystal is injected to complete the flat panel display panel.

A flat panel display panel (FDP) is classified into a device using an inorganic material and a device using an organic material based on the material used. Devices using inorganic materials include plasma display panels (PDPs) using PL (photo luminescence) and field emission displays (FEDs) using CE (Cathode Luminescence), and organic materials. Examples of the device to be used include a liquid crystal display (LCD) and an organic light emitting display (OLED). Therefore, in the manufacturing method of the flat panel display panel of the present invention, the panel manufacturing step (S31) can be applied to all flat panel display devices using a glass substrate, the detailed description of the panel manufacturing step (S31) is the respective elements It can be applied differently depending on. Accordingly, the manufacturing steps of the panel for completing the respective devices can be implemented in the prior art, so a detailed description thereof will be omitted.

The embodiments of the present invention described above and illustrated in the drawings should not be construed as limiting the technical idea of the present invention. The protection scope of the present invention is limited only by the matters described in the claims, and those skilled in the art can change and change the technical idea of the present invention in various forms. Therefore, such improvements and modifications will fall within the protection scope of the present invention, as will be apparent to those skilled in the art.

1 is a perspective view showing a defect generated in a general glass substrate,

2 is a schematic diagram illustrating light reflection and light absorption of a glass substrate;

3 is a block diagram showing a first embodiment of an edge inspection method of a glass substrate according to the present invention;

Figure 4 is a block diagram showing a second embodiment of the method for inspecting the edge of the glass substrate according to the present invention,

Figure 5 is a block diagram showing a third embodiment of the method for inspecting the edge of the glass substrate according to the present invention,

6 is a configuration diagram showing a first embodiment of the edge surface inspection apparatus of the glass substrate according to the present invention,

7 is a block diagram showing a second embodiment of the edge surface inspection apparatus of the glass substrate according to the present invention.

8 is a block diagram showing a preferred embodiment of a method of manufacturing a flat panel display panel according to the present invention.

<Explanation of symbols for the main parts of the drawings>

10: glass substrate 15: the ground

100: stage

200: laser beam irradiation unit

220: laser light emitting unit 240: first guide means

300: laser beam light receiving unit

320: condenser lens 340: photosensor

360: second guide means

400: control unit

500: warning unit

Claims (11)

A glass substrate alignment step of supporting and aligning the transferred glass substrate; A laser beam irradiation step of irradiating a laser beam on the edge surface of the glass substrate; A laser beam receiving step of receiving a laser beam reflected from an edge surface of the glass substrate with a photosensor; And a light amount detecting step of detecting a light amount of the laser beam received by the photosensor. The method of claim 1, A light amount determining step performed after the light amount detecting step and determining whether the detected light amount of the laser beam is within a preset light amount range; And a warning step of warning and informing the outside when the light amount is outside the preset light amount range. The method of claim 1, The glass substrate alignment step, A glass substrate photographing step of photographing the glass substrate; A glass substrate correction step of measuring the degree of alignment of the photographed glass substrate and correcting the glass substrate to be aligned within a preset alignment value; And a glass substrate fixing step of fixing the corrected glass substrate. The method of claim 1, The laser beam irradiation step, A laser beam emitting step of generating and amplifying a laser beam to emit a laser beam from the laser light emitting unit; And an edge surface guiding step of guiding the emitted laser beam to be irradiated onto the edge surface of the glass substrate. The method of claim 1, The laser beam receiving step, A laser beam condensing step of condensing a laser beam reflected from an edge surface of the glass substrate using a condensing lens; And a photo sensor guiding step of guiding the laser beam collected by the condenser lens to the photosensor. A stage for supporting and aligning the transferred glass substrate, A laser beam irradiation unit for irradiating a laser beam to the edge surface of the glass substrate; A laser beam light receiving unit for receiving a laser beam reflected from an edge surface of the glass substrate; And a control unit which receives a signal from the laser beam receiving unit and detects an amount of light of the laser beam to determine whether it is within a predetermined range of light amount. The method of claim 6, And a warning unit to warn and notify the outside when the amount of light determined by the controller is outside the range of a preset amount of light. The method of claim 6, The laser beam irradiation unit, A laser light emitting unit for generating and amplifying and irradiating a laser beam, And first guide means for guiding the laser beam irradiated from the laser light emitting unit to an edge surface of the glass substrate. The method of claim 6, The laser beam light receiving unit, A condenser lens for condensing the laser beam reflected from the edge surface of the glass substrate; And a photosensor for receiving the laser beam focused from the condenser lens. The method of claim 9, The laser beam light receiving unit, And a second guide means for guiding the laser beam collected from the condenser lens to the photosensor. The glass substrate manufacturing step of cutting the glass surface of each glass substrate to the size of the panel to be produced to a predetermined thickness of the glass substrate and polishing the edge surface of the glass substrate, and whether the edge of the polished glass substrate is defective A flat panel display including an edge inspection step of inspecting a panel and a panel manufacturing step of semi-assembling the glass substrates judged to be good and bonding them to a pair of top and bottom plates and then injecting gas or liquid crystal to complete the flat panel display panel. In the manufacturing method of the panel, The edge test step, A glass substrate alignment step of supporting and aligning the transferred glass substrate; A laser beam irradiation step of irradiating a laser beam on the edge surface of the glass substrate; A laser beam receiving step of receiving a laser beam reflected from an edge surface of the glass substrate with a photosensor; And a light amount detecting step of detecting a light amount of the laser beam received by the photosensor.

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