Inspection apparatus and inspection method for glass plate

Abstract

To provide an inspection apparatus and inspection method for a glass plate capable of detecting a defect of a glass plate with high accuracy.SOLUTION: An inspection apparatus 100 for a glass plate G for inspecting a defect D of a rectangular glass plate G includes: a table 23 on which the glass plate G is placed; a first illumination 13 configured to cause inspection light Lx to be incident on the glass plate G placed on the table 23 from a first side surface Gsx of the glass plate G; a second illumination 15 configured to cause inspection light Ly to be incident on the glass plate G placed on the table 23 from a second side surface Gsy adjacent to the first side surface Gsx of the glass plate G; and a defect detection unit 33 which detects scattered light Ls generated at the defect D of the glass plate G.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an inspection device and an inspection method for a glass plate. [Background technology]

[0002] For example, as an inspection device for glass plates for FPDs (Flat Panel Displays), a device is known that irradiates light onto both sides of the glass plate being transported on a transport path, i.e., two sides that are approximately parallel to the transport direction, and detects the scattered light from the glass plate that is scattered by defects, thereby detecting defects in the glass plate (see, for example, Patent Documents 1 to 3). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2009-216628 [Patent Document 2] Japanese Patent Publication No. 2012-7993 [Patent Document 3] Japanese Patent No. 3329233 Summary of the Invention [Problem to be solved by the invention]

[0004] However, with an inspection device like the one described above that detects defects by irradiating light onto two sides of a glass plate transported on a transport path that are approximately parallel to the transport direction, it has been difficult to detect defects such as fine scratches that have directional light with high accuracy.

[0005] SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a glass plate inspection device and an inspection method that are capable of detecting defects in a glass plate with high accuracy. [Means for solving the problem]

[0006] The present invention comprises the following configurations. (1) A glass plate inspection device for inspecting defects in a rectangular glass plate, a table on which the glass plate is placed; a first illuminator configured to irradiate inspection light onto the glass plate placed on the table from a first side surface of the glass plate; a second illuminator configured to irradiate inspection light onto the glass plate placed on the table from a second side surface of the glass plate adjacent to the first side surface; a defect detection unit that detects scattered light generated by defects in the glass plate; Equipped with Glass plate inspection equipment. (2) A glass plate inspection method for inspecting defects in a rectangular glass plate, comprising: Inspection light is incident on a first side surface of the glass plate and a second side surface adjacent to the first side surface, detecting scattered light generated by defects in the glass plate; How to inspect glass plates. [Effects of the Invention]

[0007] According to the present invention, it is possible to provide a glass sheet inspection device and an inspection method that are capable of detecting defects in a glass sheet with high accuracy. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a perspective view of a glass plate inspection device according to this embodiment. [Figure 2] FIG. 2 is a schematic side view illustrating the configuration of the glass plate inspection device according to this embodiment. [Figure 3] FIG. 3 is a schematic diagram showing the arrangement of the first illuminator and the second illuminator relative to the glass plate. [Figure 4] FIG. 4 is a schematic cross-sectional view of the glass plate and the first illuminator. [Figure 5] FIG. 5 is a block diagram showing a control system of the glass plate inspection device. [Figure 6] FIG. 6 is a diagram showing the luminance values ​​of scattered light caused by defects. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. <Inspection equipment> First, a glass plate inspection device according to this embodiment will be described. In the following drawings, arrows X and Y indicate two directions that are perpendicular to each other in a horizontal plane, and arrow Z indicates the vertical direction.

[0010] Fig. 1 is a perspective view of an inspection device 100 for a glass sheet G according to this embodiment. Fig. 2 is a schematic side view illustrating the configuration of the inspection device 100 for a glass sheet G according to this embodiment.

[0011] 1 and 2, a glass plate inspection device 100 according to this embodiment includes a mounting table 11, a first illuminator 13, a second illuminator 15, and a defect detection mechanism unit 17. The inspection device 100 is a device for detecting defects in a glass plate G.

[0012] The glass plate G to be inspected by the inspection device 100 is, for example, a thin glass plate having a thickness of approximately 0.4 mm to 2.0 mm, and is, for example, a glass plate used for flat panel displays (FPDs) such as LCDs (Liquid Crystal Displays) and OLEDs (Organic Light-Emitting Diodes).

[0013] The glass sheet G is formed into a rectangular shape in plan view by, for example, floating glass molten in a melting furnace on molten tin metal in a float bath, forming it into a smooth, band-like glass ribbon, annealing it in an annealing furnace, and then cutting it with a cutting tool. Various defects may occur in the glass sheet G during the manufacturing process, and the inspection device 100 detects defects present in the glass sheet G. Defects present in the glass sheet G include foreign matter or air bubbles mixed in during manufacturing, scratches caused by contact with conveying rollers or the like during conveyance, and the like, and include defects of approximately 10 μm to 100 μm in size. The inspection device 100 is suitable for use in detecting minute defects in the glass sheet G after chemical treatment (etching treatment), and is excellent at detecting defects such as latent scratches that are difficult to detect before chemical treatment.

[0014] The mounting table 11 is provided on the top of a stand 21. A table 23 is arranged on the top of the mounting table 11. A rectangular glass plate G to be inspected is, for example, taken out from a production line and placed on the table 23 of the mounting table 11.

[0015] The first illuminator 13 and the second illuminator 15 are disposed on the mounting table 11. The first illuminator 13 and the second illuminator 15 each have a light source such as an LED (Light Emitting Diode) and are formed in an elongated shape. Note that the light source of the first illuminator 13 and the second illuminator 15 is not limited to an LED, and various light sources such as a metal halide lamp, an extra-high pressure mercury lamp, a halogen lamp, or a xenon lamp may also be used.

[0016] 3 is a schematic diagram showing the arrangement of the first illuminator 13 and the second illuminator 15 relative to the glass plate G. FIG. 4 is a schematic cross-sectional view of the glass plate G and the first illuminator 13.

[0017] 3 and 4, the first illuminator 13 and the second illuminator 15 have light-projecting surfaces 13a and 15a on one side thereof, and emit linear inspection light Lx and Ly from the light-projecting surfaces 13a and 15a. In the mounting table 11, the first illuminator 13 is disposed along the Y direction at one edge of the table 23 in the X direction, and the second illuminator 15 is disposed along the X direction at one edge of the table 23 in the Y direction. In this way, the first illuminator 13 and the second illuminator 15 are disposed orthogonal to each other at the edge of the table 23, and emit inspection light Lx and Ly in directions orthogonal to each other.

[0018] The first illuminator 13 and the second illuminator 15 are arranged so that their light-projecting surfaces 13a, 15a are approximately perpendicular to the main surface of the table 23. As a result, the inspection light Lx emitted from the light-projecting surface 13a of the first illuminator 13 is incident on the glass plate G placed on the table 23 of the mounting base 11 from the first side surface Gsx, which is one side surface along the Y direction, and the inspection light Ly emitted from the light-projecting surface 15a of the second illuminator 15 is incident on the glass plate G from the second side surface Gsy, which is one side surface along the X direction. The first side surface Gsx and the second side surface Gsy, on which the inspection lights Lx, Ly are incident, are side surfaces of the glass plate G adjacent to each other.

[0019] The first illuminator 13 is rotatable about an axis in the Z direction within the same plane as the main surface of the glass plate G placed on the table 23, i.e., within the XY plane. This allows the first illuminator 13 to be rotated and adjusted to be positioned snugly relative to the first side surface Gsx of the glass plate G placed on the table 23. In other words, the inspection light Lx emitted from the light-projecting surface 13a of the first illuminator 13 can be made to be uniformly incident on the first side surface Gsx of the glass plate G over the entire length. Furthermore, the first illuminator 13 is tiltable about an axis in the substantially Y direction relative to the first side surface Gsx of the glass plate G placed on the table 23. This allows the first illuminator 13 to adjust the irradiation angle of the inspection light Lx with respect to the first side surface Gsx of the glass plate G placed on the table 23. In other words, the angle of incidence of the inspection light Lx irradiated from the projection surface 13a of the first lighting 13 onto the first side surface Gsx of the glass plate G can be adjusted, so that the inspection light Lx can be efficiently totally reflected within the glass plate G.

[0020] Similarly, the second illuminator 15 is rotatable about an axis in the Z direction within the same plane as the main surface of the glass plate G placed on the table 23, i.e., within the XY plane. This allows the second illuminator 15 to be rotated and adjusted in position so as to be positioned snugly relative to the second side surface Gsy of the glass plate G placed on the table 23. In other words, the inspection light Ly emitted from the light-projecting surface 15a of the second illuminator 15 can be made to be uniformly incident on the second side surface Gsy of the glass plate G over the entire length. Furthermore, the second illuminator 15 is tiltable about an axis extending substantially in the X direction relative to the second side surface Gsy of the glass plate G placed on the table 23. This allows the second illuminator 15 to adjust the irradiation angle of the inspection light Ly with respect to the second side surface Gsy of the glass plate G placed on the table 23. In other words, the angle of incidence of the inspection light Ly irradiated from the projection surface 15a of the second illumination 15 onto the second side surface Gsy of the glass plate G can be adjusted, so that the inspection light Ly can be completely reflected within the glass plate G.

[0021] The first illuminator 13 and the second illuminator 15 are preferably rotatable within the same plane as the main surface of the glass plate G placed on the table 23, i.e., within the XY plane, by a rotation angle of approximately ±2° around the Z direction as an axis. The first illuminator 13 is preferably tiltable with respect to the first side surface Gsx of the glass plate G placed on the table 23 by a tilt angle of approximately ±30° around an axis approximately in the Y direction, and the second illuminator 15 is preferably tiltable with respect to the second side surface Gsy by a tilt angle of approximately ±30° around an axis approximately in the X direction. That is, the incident angle of the inspection light Lx emitted from the light-projecting surface 13a of the first illuminator 13 to the first side surface Gsx of the glass plate G and the incident angle of the inspection light Ly emitted from the light-projecting surface 15a of the second illuminator 15 to the second side surface Gsy of the glass plate G are preferably adjustable within a range of approximately -30° to 30°.

[0022] The defect detection mechanism section 17 has a moving mechanism 31, a defect detection section 33, and a microscope (imaging section) 35. The defect detection section 33 and the microscope 35 are mounted on the moving mechanism 31.

[0023] The movement mechanism 31 has a gate-shaped frame 41. The lower portions of both ends of the frame 41 serve as legs 43. These legs 43 are provided with linear motion mechanisms 45, which are movably supported on rails 34 extending along the X direction on both sides of the mounting table 11. The frame 41 is disposed so as to straddle the table 23 in the Y direction, and is capable of reciprocating movement above the table 23 in the X direction by the linear motion mechanisms 45.

[0024] The defect detection unit 33 is mounted on one surface 41a of the frame 41. The defect detection unit 33 is composed of multiple cameras 51. The multiple cameras 51 constituting the defect detection unit 33 are aligned in the Y direction and supported on one surface 41a of the frame 41 with each facing downward. The defect detection unit 33 captures and detects scattered light Ls from the glass plate G placed on the table 23 using the multiple cameras 51 and outputs the detection data. The defect detection unit 33 is capable of detecting scattered light Ls from the glass plate G placed on the table 23 over the entire area in the Y direction using the multiple cameras 51 arranged in the Y direction. Therefore, by moving the defect detection unit 33 mounted on the frame 41 in the X direction using the movement mechanism 31, the defect detection unit 33 can detect scattered light Ls over the entire area of ​​the glass plate G.

[0025] The microscope 35 is mounted on the other surface 41b of the frame 41. The microscope 35 is equipped with an electronic camera, and has an autofocus lens unit 35a at its lower end. The microscope 35 is supported on the frame 41 via a microscope movement mechanism 55. The microscope 35 is moved by the microscope movement mechanism 55 in the Y direction, which is the longitudinal direction of the frame 41, and in the Z direction, which is the up-and-down direction. The microscope 35 magnifies and photographs defective portions of the glass plate G placed on the table 23, and outputs the image data.

[0026] FIG. 5 is a block diagram showing a control system of the inspection device 100 for the glass sheet G. As shown in FIG. 5, the inspection apparatus 100 includes a control unit (PLC: Programmable Logic Controller) 61. The control unit 61 is connected to the first illuminator 13, the second illuminator 15, the moving mechanism 31, and the microscope moving mechanism 55. The control unit 61 controls the on / off of the first illuminator 13 and the second illuminator 15. In the defect detection mechanism unit 17, the control unit 61 controls the operations of the moving mechanism 31 and the microscope moving mechanism 55. The control unit 61 is also connected to a microscope control unit 64 and an inspection control unit 62. The microscope control unit 64 controls the microscope 35 based on a control signal from the control unit 61, and receives image data from the microscope 35. The inspection control unit 62 is, for example, a personal computer (PC), and controls the defect detection unit 33 and receives detection data from the defect detection unit 33. The inspection control unit 62 detects defects D in the glass plate G and determines the positions of the defects D based on the detection data from the defect detection unit 33. The inspection control unit 62 also includes a display unit 63 such as a display. Inspection result data is transmitted from the inspection control unit 62 to the display unit 63, whereby defect information, which is information about defects D present in the glass plate G, is displayed. Examples of this defect information include an image of the defect D, the position of the defect D on the glass plate G, and the size of the defect D.

[0027] The illuminance of the inspection light Lx, Ly incident from the adjacent first side surface Gsx and second side surface Gsy of the glass plate G decreases with increasing distance from the incident end. Therefore, the luminance of the scattered light Ls generated by the defect D also decreases with increasing distance from the incident end of the inspection light Lx, Ly, and the detection sensitivity of the camera 51 of the defect detection unit 33 for the scattered light Ls decreases. For this reason, the control unit 61 is provided with a correction table (threshold value) that corrects the decrease in detection sensitivity due to the decrease in illuminance depending on the distance from the incident end, which is set in advance, and is equipped with a correction function that corrects and equalizes the detection sensitivity of the scattered light Ls based on this correction table. Note that this correction function may automatically adjust the aperture of the camera 51 constituting the defect detection unit 33 according to the distance from the incident end of the inspection light Lx, Ly.

[0028] <Testing method> Next, a procedure for inspecting the glass sheet G using the glass sheet inspection device 100 having the above configuration will be described.

[0029] First, for example, a rectangular glass plate G taken out from a production line is placed on the table 23 of the mounting base 11 of the inspection device 100. As a result, the light-projecting surface 13a of the first illuminator 13 is arranged to face one first side surface Gsx of the glass plate G along the Y direction, and the light-projecting surface 15a of the second illuminator 15 is arranged to face one second side surface Gsy of the glass plate G along the X direction (see FIGS. 3 and 4).

[0030] Here, the glass sheet G of this embodiment has a top surface (upper surface) Gt that becomes the front surface when formed in a float bath, and a bottom surface (lower surface) Gb that is the conveying surface that comes into contact with molten tin metal and then comes into contact with conveying rollers or the like when conveyed by a conveying device. In order to detect defects in the glass sheet G with a certain degree of accuracy, it is preferable to arrange the glass sheet G on the table 23 so that the same surface of the glass sheet G always faces upward. In particular, it is preferable to arrange the glass sheet G so that the top surface (upper surface) Gt always faces upward, that is, so that the bottom surface (lower surface) Gb always faces downward.

[0031] Next, the inspection device 100 is operated to start the inspection. When the inspection by the inspection device 100 is started, the control unit 61 turns on the first illuminator 13 and the second illuminator 15. As a result, the inspection lights Lx and Ly irradiated from the light-projecting surfaces 13a and 15a of the first illuminator 13 and the second illuminator 15 are incident on the adjacent first side surface Gsx and second side surface Gsy of the glass plate G.

[0032] When the inspection lights Lx and Ly are incident on the glass plate G, in the defect detection mechanism 17, the frame 41 of the movement mechanism 31 moves in the X direction, and the multiple cameras 51 of the defect detection unit 33 detect scattered light Ls, which is the inspection lights Lx and Ly scattered by defects D and emitted from the top surface Gt of the glass plate G. In this way, the defect detection unit 33 detects scattered light Ls from the entire region of the glass plate G.

[0033] Incidentally, some defects D present in the glass plate G have optical directionality. In such defects D having optical directionality, the irradiated inspection light Lx or Ly passes through without any change, and there are cases where almost no scattered light Ls is generated.

[0034] Here, for a glass plate G having optical directionality and having minute defects D1, D2, and D3 with lengths of 20 μm, 35 μm, and 55 μm, the luminance values ​​of scattered light Ls were measured when the first side surface Gsx was irradiated with inspection light Lx, when the second side surface Gsy was irradiated with inspection light Ly, and when the first side surface Gsx and the second side surface Gsy were irradiated with inspection light Lx and LY. Figure 6 shows the luminance values ​​of scattered light Ls generated by defects D1, D2, and D3.

[0035] As shown in Figure 6, when inspection light Lx was irradiated onto the first side surface Gsx of glass plate G, scattered light Ls with a brightness equal to or greater than the detectable brightness cd was generated at the 20 μm and 35 μm defects D1 and D2, but no scattered light Ls with a brightness equal to or greater than the detectable brightness cd was generated at the 55 μm defect D3. On the other hand, when inspection light Ly was irradiated onto the second side surface Gsy of glass plate G, scattered light Ls with a brightness equal to or greater than the detectable brightness cd was generated at the 55 μm defect D3, but no scattered light Ls with a brightness equal to or greater than the detectable brightness cd was generated at the 20 μm and 35 μm defects D1 and D2. Under these circumstances, when inspection light Lx and Ly were irradiated onto the first side surface Gsx and the second side surface Gsy of glass plate G, respectively, scattered light Ls with a brightness equal to or greater than the detectable brightness cd was generated at the 20 μm, 35 μm, and 55 μm defects D1, D2, and D3, respectively.

[0036] In the inspection method using the inspection device 100 of this embodiment, the first illumination 13 and the second illumination 15 are used to cause inspection light Lx and Ly to be incident from the adjacent first side Gsx and second side Gsy of the rectangular glass plate G, respectively, so that defects D having optical directionality can be detected with high accuracy.

[0037] When the defect detection unit 33 detects a defect D in the glass plate G, the control unit 61 executes an imaging process for the defect D based on the detection data. In this imaging process, the microscope 35 is moved by the movement mechanism 31 and the microscope movement mechanism 55 to the position of each defect D detected in the glass plate G. Then, at the position of the defect D, the defect D is imaged by the microscope 35, and the imaging data is transmitted to the control unit 61 and the inspection control unit 62. In this imaging process for the defect D by the microscope 35, continuous imaging is performed by the microscope 35, which is moved in the vertical direction by the microscope movement mechanism 55.

[0038] The inspection control unit 62 causes the display unit 63 to display defect information consisting of the detection data of the defect D from the defect detection unit 33 and the imaging data from the microscope 35. Based on the defect information, the display unit 63 displays an image of the defect D, the position of the defect D in the glass plate G, the size of the defect D, and the like. Therefore, by referring to the display of the defect information on the display unit 63, the inspector can easily and accurately confirm and identify the position, type, and size of the defect D in the glass plate G.

[0039] As described above, according to the inspection device 100 and inspection method for glass plate G of this embodiment, defects D are detected by irradiating inspection light Lx and Ly from the adjacent first side surface Gsx and second side surface Gsy of the rectangular glass plate G, respectively.Therefore, compared to, for example, a device that detects defects D by irradiating light onto both sides of the glass plate G being transported on a production line, i.e., two side surfaces that are approximately parallel to the transport direction, even defects D such as fine scratches with directional light can be detected with high accuracy.

[0040] Furthermore, since the microscope 35 photographs the location where the scattered light Ls is detected by the defect detection unit 33 with high precision, the size, type, etc. of the defect D in the glass plate G can be determined accurately.

[0041] Furthermore, since the defect detection unit 33 and the microscope 35 are mounted on the same moving mechanism 31 and moved parallel to the glass plate G, the deviation between the detection position of the scattered light Ls by the defect detection unit 33 and the photographing position of the scattered light Ls by the microscope 35 can be suppressed.

[0042] Furthermore, according to the inspection method of this embodiment, when inspecting defects D with the inspection device 100, the glass plate is placed with its bottom surface Gb, which serves as the transport surface in the manufacturing process, facing downward, so that defects D on the bottom surface Gb that occurred during manufacturing, transport, etc. can be detected efficiently and with high accuracy. Furthermore, by inspecting the glass plate G after chemical treatment, defects D such as latent scratches that are difficult to identify before chemical treatment can be detected with high accuracy.

[0043] In the above embodiment, an example was given of the case where the inspection light Lx, Ly is incident from the first side surface Gsx, which is one of the side surfaces of the glass plate G that run along the Y direction, and the second side surface Gsy, which is one of the side surfaces of the glass plate G that run along the X direction, but the inspection light may also be incident from the first side surface Gsx and the opposite surface of the first side surface Gsx, and the second side surface Gsy and the opposite surface of the second side surface Gsy.

[0044] As such, the present invention is not limited to the above-described embodiments, and the present invention also contemplates the mutual combination of the various components of the embodiments, as well as modifications and applications by those skilled in the art based on the description in the specification and well-known techniques, and these modifications and applications are included in the scope of protection sought.

[0045] As described above, the present specification discloses the following: (1) A glass plate inspection device for inspecting defects in a rectangular glass plate, a table on which the glass plate is placed; a first illuminator configured to irradiate inspection light onto the glass plate placed on the table from a first side surface of the glass plate; a second illuminator configured to irradiate inspection light onto the glass plate placed on the table from a second side surface of the glass plate adjacent to the first side surface; a defect detection unit that detects scattered light generated by defects in the glass plate; A glass plate inspection device comprising: This glass plate inspection device detects defects by irradiating inspection light onto adjacent first and second side surfaces of a rectangular glass plate. Therefore, compared to devices that detect defects by irradiating light onto two side surfaces that are approximately parallel to the transport direction of a glass plate being transported on a production line, it can accurately detect defects such as fine scratches that have directional light.

[0046] (2) The glass plate inspection device according to (1), further comprising an imaging unit that captures an image of a location where scattered light is detected by the defect detection unit. According to this glass plate inspection device, the size and type of defects in the glass plate can be accurately determined by using the imaging unit to capture an image of the location where scattered light is detected with high precision.

[0047] (3) The glass plate inspection device according to (2), further comprising a moving mechanism configured to be movable parallel to the main surface of the table, the defect detection unit and the imaging unit being mounted on the moving mechanism. According to this glass plate inspection device, the defect detection unit and the imaging unit are mounted on the same moving mechanism and moved parallel to the glass plate, thereby suppressing the deviation between the detection position of scattered light by the defect detection unit and the photographing position of scattered light by the imaging unit.

[0048] (4) A glass plate inspection device according to any one of (1) to (3), wherein at least one of the first illuminator and the second illuminator is configured to be rotatable within the same plane as the main surface of the glass plate placed on the table. According to this glass plate inspection device, the first illuminator and / or the second illuminator can be rotated in the same plane as the main surface of the glass plate, i.e., in the XY plane, around the Z axis, so that the first illuminator and the second illuminator can be positioned parallel with high precision to the adjacent first and second side surfaces of the glass plate on the table. This allows the inspection light to be effectively incident from the first and second side surfaces, improving inspection precision.

[0049] (5) A glass plate inspection device described in any one of (1) to (4), wherein at least one of the first illuminator and the second illuminator is configured to be tiltable with respect to the corresponding first side or second side of the glass plate placed on the table. According to this glass plate inspection device, the tilt of the first illuminator can be adjusted by tilting the first illuminator about an axis in the Y direction relative to the first side surface, and / or the tilt of the second illuminator can be adjusted by tilting the second illuminator about an axis in the X direction relative to the second side surface, thereby enabling the inspection light incident from the first and second side surfaces to be accurately totally reflected inside the glass plate, thereby improving inspection accuracy.

[0050] (6) A glass plate inspection device described in any one of (1) to (5), wherein at least one of the first illuminator and the second illuminator is configured so that the angle of incidence of the inspection light emitted therefrom onto the corresponding first side surface or second side surface of the glass plate can be adjusted. This glass plate inspection device can adjust the angle of incidence of the inspection light emitted from the first illuminator onto the first side surface and / or the angle of incidence of the inspection light emitted from the second illuminator onto the second side surface, thereby enabling the inspection light incident from the first and second side surfaces to be accurately totally reflected inside the glass plate, improving inspection accuracy.

[0051] (7) A glass plate inspection method for inspecting a glass plate formed in a rectangular shape for defects, comprising: Inspection light is incident on a first side surface of the glass plate and a second side surface adjacent to the first side surface, A glass plate inspection method comprising detecting scattered light generated by defects in the glass plate. According to this glass plate inspection method, defects are detected by irradiating inspection light from adjacent first and second side surfaces of the glass plate. Therefore, defects such as minute scratches with directional light can be detected with high accuracy compared to, for example, a case where defects are detected by irradiating light onto both sides of a glass plate being transported on a production line, i.e., two side surfaces parallel to the transport direction.

[0052] (8) A method for inspecting a glass plate according to (7), wherein the glass plate is placed with the lower surface of the glass plate, which serves as a conveying surface in the manufacturing process, facing vertically downward, and scattered light is detected from the upper surface side of the glass plate. According to this glass plate inspection method, defects on the lower surface, which is the conveying surface of the glass plate, that occur during manufacturing, conveyance, etc. can be detected efficiently and with high accuracy.

[0053] (9) The method for inspecting a glass plate according to (7) or (8), wherein the glass plate is inspected after the chemical treatment. According to this glass plate inspection method, defects such as latent scratches that are difficult to detect before chemical treatment can be detected with high accuracy. [Explanation of symbols]

[0054] 13 First Lighting 15 Second Lighting 23 Tables 31 Moving mechanism 33 Defect detection section 35 Microscope (imaging unit) 100 Inspection equipment Ls scattered light Lx, Ly inspection light D. Defect G Glass plate Gsx 1st side Gsy 2nd side Gb Bottom surface (lower surface) Gt top surface (upper surface)

Claims

1. A glass plate inspection device that inspects defects in a rectangular glass plate, a table on which the glass plate is placed; a first illuminator configured to irradiate inspection light onto the glass plate placed on the table from a first side surface of the glass plate; a second illuminator configured to irradiate inspection light onto the glass plate placed on the table from a second side surface of the glass plate adjacent to the first side surface; a defect detection unit that detects scattered light generated by defects in the glass plate; Equipped with Glass plate inspection equipment.

2. an imaging unit that captures an image of a location where scattered light is detected by the defect detection unit; The glass plate inspection device according to claim 1 .

3. a moving mechanism configured to be movable in parallel with the main surface of the table; the defect detection unit and the imaging unit are mounted on the moving mechanism; The glass plate inspection device according to claim 2 .

4. At least one of the first illuminator and the second illuminator is configured to be rotatable within the same plane as a main surface of the glass plate placed on the table. The glass plate inspection device according to claim 1 .

5. At least one of the first illuminator and the second illuminator is configured to be inclined with respect to a corresponding first side surface or a second side surface of the glass plate placed on the table. The glass plate inspection device according to any one of claims 1 to 4.

6. At least one of the first illuminator and the second illuminator is configured so that an incident angle of the inspection light emitted therefrom onto the corresponding first side surface or the second side surface of the glass plate can be adjusted. The glass plate inspection device according to any one of claims 1 to 4.

7. A glass plate inspection method for inspecting a glass plate formed in a rectangular shape for defects, comprising: Inspection light is incident on a first side surface of the glass plate and a second side surface adjacent to the first side surface, detecting scattered light generated by defects in the glass plate; How to inspect glass plates.

8. the glass plate is placed with its lower surface, which serves as a conveying surface in a manufacturing process, facing vertically downward, and scattered light is detected from the upper surface side of the glass plate. The glass plate inspection method according to claim 7 .

9. Inspecting the glass plate after chemical treatment. The glass plate inspection method according to claim 7 or 8.

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