Method for inspecting glass plate, inspection device, and method for manufacturing glass plate

Abstract

To accurately inspect the shape of a glass plate.SOLUTION: The method for inspecting a glass plate is for inspecting the shape of a glass plate G placed on a placing surface 5a formed of a plurality of protrusions 5. The glass plate G includes a reference glass plate G1 and a sample glass plate G2. The method for inspecting the glass plate G includes: a measurement step S63 for measuring the shape of a sample glass plate G2; and an evaluation step S64 for evaluating the shape of the sample glass plate G2 by comparing a reference shape determined by the reference glass plate G1 and a measured value of the shape of the sample glass plate G2.SELECTED DRAWING: Figure 8

Description

[Technical field]

[0001] The present invention relates to a method and apparatus for inspecting a glass sheet, and a method for manufacturing a glass sheet. [Background technology]

[0002] In recent years, lightweight, flexible, thin glass substrates have been used in displays such as liquid crystal displays and organic electroluminescence displays. After various films are uniformly applied to the surface of the glass substrate used in the display, thin film transistors (TFTs) are formed using photoprocessing techniques (exposure process, development process, etc.).

[0003] In order to form thin film transistors with high accuracy, high dimensional accuracy is required for the glass substrate, and therefore, in the process of manufacturing the glass plate, a step of inspecting the shape of the manufactured glass plate is carried out.

[0004] As an example of an apparatus used in such an inspection process, Patent Document 1 discloses an inspection apparatus (glass plate measuring apparatus) that includes a platen on which a glass plate is placed and an optical measuring means that uses light irradiation and reflection for measurement. The platen in this inspection apparatus has a number of grooves extending laterally on its surface (see paragraph 0030 of the same document). [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2021-148446 A Summary of the Invention [Problem to be solved by the invention]

[0006] In conventional inspection devices, the surface of the base plate is made uneven by grooves, so when a thin glass plate is placed on this surface, the glass plate bends at the grooves, making it impossible to perform highly accurate inspection of the shape of the glass plate, such as warping.

[0007] The present invention has been made in view of the above circumstances, and has as its technical object to inspect the shape of a glass sheet with high accuracy. [Means for solving the problem]

[0008] (1) The present invention is intended to solve the above-mentioned problems, and provides a method for inspecting the shape of a glass plate placed on a mounting surface, the mounting surface being formed by a plurality of convex portions, the glass plate including a reference glass plate and a sample glass plate, and comprising a measurement step of measuring the shape of the sample glass plate, and an evaluation step of evaluating the shape of the sample glass plate by comparing a reference shape determined by the reference glass plate with a measured value of the shape of the sample glass plate.

[0009] According to this configuration, by comparing the shape of the sample glass plate measured in the measurement process with a reference shape determined by a reference glass plate in the evaluation process, it is possible to accurately inspect the shape of the sample glass plate even if there are multiple grooves or other recesses on the mounting surface.

[0010] (2) The glass plate inspection method described in (1) above may further include a preparation step of measuring the shapes of a plurality of the reference glass plates, and a calculation step of calculating the reference shapes from measurement values ​​obtained in the preparation step.

[0011] According to this configuration, by calculating the reference shape based on a plurality of reference glass plates in the preparation step, it is possible to improve the accuracy of the reference shape that serves as an evaluation standard for the sample glass plates.

[0012] (3) In the glass plate inspection method described in (2) above, in the calculating step, an average value of shapes of a plurality of the reference glass plates may be calculated as the reference shape.

[0013] According to this configuration, by using the average value of the shapes of a plurality of reference glass plates as the reference shape, it is possible to further improve the accuracy of the reference shape that serves as the evaluation standard for the sample glass plates.

[0014] (4) In the glass plate inspection method described in any one of (1) to (3) above, in the preparation step, the shape of the upper surface of the reference glass plate may be measured while the reference glass plate is placed on the mounting surface, and in the measurement step, the shape of the upper surface of the sample glass plate may be measured while the sample glass plate is placed on the mounting surface.

[0015] (5) In the glass plate inspection method described in any one of (1) to (3) above, the convex portion may be formed by a long member, the support surface may be constructed by arranging the long members in a line at a predetermined interval, the width of the convex portion may be 50 mm or more and 200 mm or less, and the interval between the convex portions may be 50 mm or more and 200 mm or less.

[0016] (6) A method for producing a glass plate according to the present invention is provided to solve the above-mentioned problems, and is characterized in that an inspection step is carried out using the glass plate inspection method according to any one of (1) to (5) above.

[0017] (7) The present invention is intended to solve the above-mentioned problems, and provides a glass plate inspection device comprising a mounting surface for mounting a glass plate, and a measurement unit for measuring a shape of the glass plate mounted on the mounting surface, wherein the mounting surface is composed of a plurality of convex portions, and the glass plate includes a reference glass plate and a sample glass plate, and the device is characterized in comprising a memory unit for storing a reference shape determined by the reference glass plate, and an evaluation unit for evaluating the shape of the sample glass plate by comparing the shape of the sample glass plate with the reference shape.

[0018] According to this configuration, the shape of the sample glass plate measured by the measurement unit is compared with a reference shape by the evaluation unit, making it possible to accurately inspect the shape of the sample glass plate even if there are multiple grooves or other recesses on the mounting surface. Effect of the Invention

[0019] According to the present invention, the shape of a glass plate can be inspected with high precision. [Brief description of the drawings]

[0020] [Figure 1] FIG. [Diagram 2] FIG. [Diagram 3] 3 is a cross-sectional view of the placement portion taken along the line of arrows III-III in FIG. 2. [Figure 4] 11 is a side view showing the operation of a positioning unit of the inspection apparatus. FIG. [Diagram 5] 11 is a front view showing the operation of a positioning unit of the inspection apparatus. FIG. [Figure 6] FIG. 2 is a block diagram showing a control unit of the inspection apparatus. [Figure 7] 1 is a flowchart showing a method for manufacturing a glass plate. [Figure 8] 1 is a flowchart showing an inspection process. [Figure 9] FIG. [Figure 10] FIG. [Figure 11] FIG. [Figure 12] FIG. [Figure 13] FIG. [Figure 14] FIG. [Figure 15] FIG. [Figure 16] FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Figures 1 to 16 show an embodiment of a glass plate inspection device and a glass plate manufacturing method using this inspection device according to the present invention.

[0022] As shown in Figures 1 and 2, the inspection device 1 includes a mounting section 2 for mounting a glass plate G, a measurement section 3 for measuring the shape of the glass plate G mounted on the mounting section 2, and a control section 4 for controlling the mounting section 2 and the measurement section 3.

[0023] The glass plate G to be inspected is, for example, a rectangular original glass plate (mother glass plate) from which one or more product glass plates are taken. The thickness of the original glass plate and the product glass plate is, for example, 0.05 mm to 1.2 mm. The size of the original glass plate is, for example, 1000 mm×1000 mm to 3500 mm×3500 mm, and the size of the product glass plate is, for example, 700 mm×700 mm to 3500 mm×3500 mm. The product glass plate is used, for example, as a substrate or cover glass of a display. Note that the substrate and cover glass of the display are not limited to a flat panel, and may be used for a curved panel or a foldable panel.

[0024] Hereinafter, one surface of the glass plate G will be referred to as a first main surface Ga, and the other surface will be referred to as a second main surface Gb. In addition, the sides of the glass plate G will be referred to as a first side GS1, a second side GS2, a third side GS3, and a fourth side GS4.

[0025] The placement unit 2 includes a plurality of base plates 5, a plurality of support members 6 provided between the base plates 5, positioning units 7a and 7b for positioning the glass sheet G, and a guide member 8 for guiding the glass sheet G to the base plates 5.

[0026] The surface plate 5 is an elongated member, and is arranged such that its longitudinal direction is aligned with the carry-in direction A1 and the carry-out direction A2 of the glass sheet G. The surface plate 5 is made of a metal such as an aluminum alloy. An upper surface 5a of the surface plate 5 functions as a placement surface on which the glass sheet G is placed. The upper surface 5a of the surface plate 5 has a plurality of ejection holes 5b for ejecting gas.

[0027] The multiple base plates 5 are arranged at predetermined intervals in the width direction X perpendicular to the longitudinal direction Y. Due to this arrangement, a groove 9 is formed between two adjacent base plates 5. The mounting part 2 is configured by alternately arranging the base plates 5 and the grooves 9. In other words, the mounting part 2 is configured by alternately providing convex portions formed by the base plates 5 and concave portions formed by the grooves 9.

[0028] The width W (width of the upper surface 5a) of the base plate 5 as a convex portion is preferably 50 mm or more and 200 mm or less. The lower limit of the width W is more preferably 80 mm or more, and even more preferably 100 mm or more. The upper limit of the width W is more preferably 180 mm or less, and even more preferably 150 mm or less. The interval D of the base plate 5 in the width direction X, i.e., the width of the groove portion 9, is preferably 50 mm or more and 200 mm or less. The lower limit of the interval D is more preferably 70 mm or more, and even more preferably 80 mm or more. The upper limit of the interval D is more preferably 180 mm or less, and even more preferably 150 mm or less.

[0029] The upper surfaces 5a of the multiple bases 5 arranged at regular intervals form a rectangular mounting surface for mounting a glass plate G. As shown in Fig. 1 and Fig. 2, the mounting surface has a first corner 10a, a second corner 10b, a third corner 10c, and a fourth corner 10d.

[0030] 3, the mounting surface is configured as an inclined surface that gradually slopes downward in the diagonal direction, i.e., from the third corner 10c to the first corner 10a. The angle θ that the mounting surface makes with the horizontal direction (horizon H) is preferably 0.1° or more and 5° or less.

[0031] The support members 6 are disposed between adjacent base plates 5 in the width direction X. In other words, the support members 6 are provided within the range of the groove portions 9 in the mounting portion 2. The multiple support members 6 are disposed at predetermined intervals in the longitudinal direction Y of the base plates 5.

[0032] The support member 6 is configured to be movable in the up-down direction. Specifically, the support member 6 is configured to be movable between a standby position located below the upper surface 5a of the base plate 5 and a support position above the upper surface 5a of the base plate 5 to support the glass sheet G.

[0033] The positioning portions 7a and 7b include a first positioning portion 7a and a second positioning portion 7b. The first positioning portion 7a contacts a first side GS1 of the glass plate G placed on the placement portion 2 to position the first side GS1, and the second positioning portion 7b contacts a second side GS2 of the glass plate G placed on the placement portion 2 to position the second side GS2.

[0034] Each of the positioning units 7a, 7b is configured to be movable in the vertical and horizontal directions. As shown in Fig. 4, the first positioning unit 7a is configured to be movable vertically between a standby position (position indicated by a solid line) located below the upper surface 5a of the base plate 5 and a retreat position (position indicated by a dashed line) located above the standby position and horizontally separated from the first side GS1 of the glass sheet G. Furthermore, the first positioning unit 7a is configured to be movable horizontally between this retreat position and a positioning position (position indicated by a dashed line) where it comes into contact with the first side GS1 of the glass sheet G.

[0035] 5, the second positioning unit 7b is configured to be movable up and down between a standby position (position indicated by a solid line) located below the upper surface 5a of the base plate 5 and a retracted position (position indicated by a dashed line) above the standby position and horizontally separated from the second side GS2 of the glass sheet G. Furthermore, the second positioning unit 7b is configured to be movable horizontally between this retracted position and a positioning position (position indicated by a dashed line) where it comes into contact with the second side GS2 of the glass sheet G.

[0036] The guide member 8 is provided at a position away from an end of the base plate 5 in the longitudinal direction Y. In this embodiment, the guide member 8 is formed of, for example, a guide roller that contacts the second main surface Gb, which is the lower surface of the glass sheet G. The configuration of the guide member 8 is not limited to this embodiment.

[0037] As shown in FIGS. 1 and 2, the measurement unit 3 includes a sensor unit 11 and drive units 12a and 12b that move the sensor unit 11.

[0038] The sensor unit 11 is configured by, for example, a laser displacement meter, but the configuration of the sensor unit 11 is not limited to this embodiment. The sensor unit 11 is preferably configured by a non-contact type displacement meter such as a laser displacement meter or an ultrasonic displacement meter.

[0039] The driving units 12a, 12b include a first driving unit 12a that supports the sensor unit 11, and a second driving unit 12b that supports the first driving unit 12a. The first driving unit 12a has an elongated first support unit 13 that extends along the width direction X, and a second support unit 14 that supports an end of the first support unit 13. The first support unit 13 is configured to reciprocate the sensor unit 11 along the width direction X. The second support unit 14 is an elongated member (leg) that extends in the up-down direction.

[0040] The second driving unit 12b is configured as a pair of support bases that movably support the second support unit 14 of the first driving unit 12a. The second driving unit 12b is configured as an elongated member extending along the carry-in / carry-out directions A1, A2 of the glass sheet G. The second driving unit 12 is disposed outside the placement unit 2 in the width direction X so as to be parallel to the base plate 5.

[0041] The second driving unit 12b includes a guide rail 15 for guiding the second support unit 14 of the first driving unit 12a. With this configuration, the second driving unit 12b can reciprocate the first driving unit 12a along the longitudinal direction Y of the base 5 or the load-in / load-out directions A1, A2.

[0042] The control unit 4 is composed of a computer that controls the mounting unit 2 and the measurement unit 3 and performs various calculation processes. The control unit 4 controls the gas ejection operation from the ejection holes 5b of the base 5 in the mounting unit 2, the operation of the support member 6 in the mounting unit 2, and the operation of the sensor unit 11 and the drive units 12a and 12b in the measurement unit 3, and performs calculation processes on the data measured by the measurement unit 3, etc.

[0043] As shown in FIG. 6, the control unit 4 mainly includes a calculation processing unit 16, a storage unit 17, and a communication control unit .

[0044] The arithmetic processing unit 16 can obtain, by arithmetic processing, numerical values ​​related to the "reference shape" required for inspecting the glass sheet G. The arithmetic processing unit 16 includes an evaluation unit 19 that judges the quality of the glass sheet G to be inspected based on this reference shape.

[0045] The storage unit 17 can store various information such as various data and programs required for inspecting the glass plate G, measurement values ​​of the glass plate G, and judgment results by the evaluation unit 19 of the arithmetic processing unit 16. The communication control unit 18 can transmit and receive signals to and from the mounting unit 2 and the measurement unit 3.

[0046] Hereinafter, a method for inspecting the glass sheet G using the inspection device 1 having the above configuration and a method for manufacturing the glass sheet G will be described.

[0047] As shown in FIG. 7, the method for producing a glass sheet G includes a forming step S1, an annealing step S2, a cooling step S3, a first cutting step S4, a second cutting step S5, and an inspection step S6.

[0048] In the forming step S1, a glass ribbon is continuously formed from molten glass by a forming device. The forming device includes a forming body capable of performing an overflow downdraw method. The forming body causes molten glass to overflow from an overflow groove formed in the upper portion thereof and flow down along both side wall surfaces of the forming body. Furthermore, the forming body fuses the flowed molten glass at the lower end of each side wall surface. This forms a glass ribbon having a predetermined width. The forming body may also perform other downdraw methods such as a slot downdraw method.

[0049] The annealing step S2 is performed in an annealing furnace arranged below the forming device. In the annealing step S2, the glass ribbon is conveyed downward by a pair of rollers arranged in the annealing furnace. A predetermined temperature gradient is set in the annealing furnace, and the glass ribbon is annealed by passing through the annealing furnace. In the cooling step S3 after the annealing step S2, the glass ribbon is cooled to about room temperature while passing through a cooling zone arranged below the annealing furnace.

[0050] In the first cutting step S4, a first cutting device arranged below the cooling zone cuts the middle portion of the glass ribbon along the width direction to cut out a glass sheet G of a predetermined size. That is, in the first cutting step S4, a scribe line along the width direction is formed by a scribing device in the middle portion of the glass ribbon moving downward (scribing step), and a portion of the glass ribbon is bent and split along the scribe line to form a sheet-like glass sheet G (bending and splitting step).

[0051] The second cutting step S5 is a step of removing an end (unnecessary portion) in the width direction of the glass sheet G cut out in the first cutting step S4. In the second cutting step S5, similar to the first cutting step S4, a scribe line is formed in a part of the glass sheet G (scribing step), and then the end of the glass sheet G is bent and broken by a breaking device (breaking step).

[0052] In the inspection step S6, the shape of the glass sheet G is measured by the inspection device 1, and the quality of the glass sheet G is judged based on the measured value.

[0053] As shown in FIG. 8, the inspection process S6 includes a preparation process S61, a calculation process S62, a measurement process S63, and an evaluation process S64.

[0054] In the preparation step S61, first, a plurality of glass plates (hereinafter referred to as "reference glass plates") G1 that serve as inspection standards are selected from the glass plates G formed through the second cutting step S5. The reference glass plates can be composed of, for example, 3 to 10 non-defective glass plates. Thereafter, the shape of the reference glass plate G1 is measured by the inspection device 1 to obtain data related to the "reference shape" used in the evaluation step S64. A specific embodiment of the preparation step S61 will be described below.

[0055] As shown in FIG. 1 and FIG. 2, in the preparation step S61, the reference glass plate G1 is carried into the placement unit 2. In this carrying step, the first main surface Ga of the reference glass plate G1 is the upper surface, and the second main surface Gb is the lower surface. The reference glass plate G1 is sent to the base plate 5 along the carrying direction A1 with the second main surface Gb in contact with the guide member 8. At this time, the guide member 8 guides the second main surface Gb of the reference glass plate G1 along the carrying direction A1 while rotating. In addition, in the carrying step, gas is ejected from the ejection hole 5b under the control of the control unit 4. This avoids contact between the reference glass plate G1 and the base plate 5, and prevents damage to the reference glass plate G1 in the carrying step. While the reference glass plate G1 is carried into the placement unit 2, the positioning units 7a and 7b are in the standby position and do not come into contact with the reference glass plate G1.

[0056] As shown in FIGS. 4 and 5, when the reference glass plate G1 is carried into the mounting unit 2, the positioning units 7a and 7b move from the standby position to the retracted position, and then move from the retracted position to the contact position.

[0057] Thereafter, the surface plate 5 stops the gas ejection. As a result, the reference glass plate G1 comes into contact with the upper surface 5a of the surface plate 5. At this time, the upper surface 5a of the surface plate 5 guides the reference glass plate G1 along the inclination direction, that is, along the direction from the third corner 10c of the mounting surface toward the first corner 10a. As a result, the first side GS1 of the reference glass plate G1 comes into contact with the first positioning portion 7a at the contact position. Also, the second side GS2 of the reference glass plate G1 comes into contact with the second positioning portion 7b at the contact position. As a result, the reference glass plate G1 is positioned at the reference measurement position where it can be measured by the measurement unit 3.

[0058] Next, under the control of the control unit 4, the measurement unit 3 measures the shape of the reference glass plate G1 placed on the placement unit 2. Specifically, the measurement unit 3 measures the amount of warping (hereinafter referred to as the "first amount of warping") of the reference glass plate G1 when placed on the placement surface (upper surface 5a of the base plate 5) and the amount of warping (hereinafter referred to as the "second amount of warping") of the reference glass plate G1 when it is raised above the placement surface.

[0059] 9, the sensor unit 11 measures the first warpage amount of the reference glass plate G1 while moving along the width direction X. That is, while moving above the groove portion 9 in the width direction X, the sensor unit 11 irradiates the first main surface Ga of the reference glass plate G1 with laser light L and receives the laser light L reflected from the first main surface Ga to measure the distance (first warpage amount) from the sensor unit 11 to the first main surface Ga of the reference glass plate G1.

[0060] In the preparation step S61, the sensor unit 11 measures the first warpage amount for a plurality of reference glass plates G1. As shown in FIG. 10, a plurality of measurement points MP (measurement areas) are set on each reference glass plate G1, and the distance between the sensor unit 11 and the first main surface Ga of the reference glass plate G1 is measured for each measurement point MP. The pitch between each measurement point MP is set to, for example, 10 mm or more and 200 mm or less. The measurement points MP may be set at an equal pitch, or may be set at different pitches depending on the position or direction on the reference glass plate G1. In this embodiment, the measurement points MP are set at an equal pitch in the width direction X and the longitudinal direction Y of the base plate 5, and the measurement points MP include positions corresponding to the convex portion (base plate 5) and positions corresponding to the concave portion (groove portion 9).

[0061] As shown by arrow B1 in Fig. 10, the sensor unit 11 measures the first warpage amount for each measurement point MP while moving along the width direction X with respect to the reference glass plate G1 placed on the placement unit 2. After completing the measurement for one row of measurement points MP along the width direction X, the sensor unit 11 moves along the longitudinal direction Y of the base plate 5 and measures the next row along the width direction X. By repeating the above procedure, the first warpage amount is measured for all measurement points MP of the reference glass plate G1. The sensor unit 11 transmits the acquired measurement data related to the first warpage amount to the communication control unit 18 of the control unit 4.

[0062] When measuring the second amount of warping, the placement unit 2 ejects gas from the ejection holes 5b of the surface plate 5 under the control of the control unit 4. As a result, as shown in FIG. 11, the reference glass plate G1 supported on the upper surface 5a of the surface plate 5 floats up from the upper surface 5a. The sensor unit 11 measures the shape of the first main surface Ga of the reference glass plate G1 while moving along the width direction X in a state in which the reference glass plate G1 floats up from the surface plate 5. That is, the sensor unit 11 irradiates the first main surface Ga of the reference glass plate G1 with laser light L while moving, and receives the laser light L reflected from the first main surface Ga to measure the distance (second amount of warping) from the sensor unit 11 to the first main surface Ga of the reference glass plate G1.

[0063] The second warpage is measured for a plurality of reference glass plates G1 in the same manner as the first warpage. The second warpage is measured for each measurement point MP set for each reference glass plate G1.

[0064] The sensor unit 11 measures the second amount of warping while repeatedly moving back and forth along the width direction X with respect to the reference glass plate G1 placed on the placement unit 2 in the same manner as in the measurement of the first amount of warping (see FIG. 10). The sensor unit 11 transmits measurement data relating to the second amount of warping to the communication control unit 18 of the control unit 4. After the preparation step S61 is completed, the used reference glass plate G1 is discarded.

[0065] The calculation step S62 is a step of calculating a reference shape from the measurement values ​​of the reference glass plate G1 obtained in the preparation step S61.

[0066] The arithmetic processing unit 16 of the control unit 4 calculates an average value of the measurement data transmitted from the measurement unit 3. That is, the arithmetic processing unit 16 calculates an average value for each measurement point of the first warpage amount (the distance between the sensor unit 11 and the first main surface Ga of the reference glass plate G1) of the multiple reference glass plates G1. The arithmetic processing unit 16 also calculates an average value for each measurement point MP of the second warpage amount of the multiple reference glass plates G1. The calculated average value becomes a reference value for determining the acceptability of the sample glass plate G2 in the subsequent evaluation step S64.

[0067] The calculation processing unit 16 creates a "reference shape" based on the calculated average value of the measurement data of each measurement point. Here, the "reference shape" means a set of reference values ​​(average values) calculated at each measurement point of the reference glass plate G1. For example, as shown in FIG. 10, the reference values ​​(average values) calculated in the preparation step S61 are set for a plurality of measurement points MP set on the reference glass plate G1. The control unit 4 causes the memory unit 17 to record data related to the reference shape.

[0068] In the measuring step S63, the shape of a sample glass plate G2 selected from the glass plate G formed through the second cutting step S5 is measured. The sample glass plate G2 may be selected, for example, every predetermined time or every predetermined number of plates. The predetermined time and the predetermined number of plates are appropriately selected depending on the manufacturing conditions and inspection results of the glass plate G. In the measuring step S63, the sample glass plate G2 is placed on the upper surface 5a of the base 5 of the placement unit 2 in the same manner as when the reference glass plate G1 was measured.

[0069] Thereafter, the measurement unit 3 of the inspection device 1 performs measurement on each measurement point MP set on the first main surface Ga of the sample glass plate G2. Note that the measurement points MP set on the sample glass plate G2 are set at the same positions as the measurement points MP set on the reference glass plate G1.

[0070] In the measurement step S63, the shape of the sample glass sheet G2, that is, the first warpage amount and the second warpage amount at each measurement point MP of the sample glass sheet G2, are measured, and the deflection difference and sheet thickness of the sample glass sheet G2 are also measured.

[0071] When measuring the deflection difference of the sample glass plate G2 in the measurement step S63, the sample glass plate G2 is supported by the support member 6. As shown in Fig. 12, the support member 6 moves from the standby position to the support position to lift up a part of the sample glass plate G2. When the support member 6 is in the support position, the upper end of the support member 6 is positioned above the upper surface 5a of the base plate 5. The sample glass plate G2 supported by the support member 6 is separated from the upper surface 5a of the base plate 5.

[0072] As shown in FIG. 12, the sensor unit 11 moves along the width direction X, irradiates laser light L onto a first principal surface Ga, which is the upper surface of the sample glass plate G2, and receives the laser light L reflected from the first principal surface Ga, thereby measuring the distance from the sensor unit 11 to the first principal surface Ga of the sample glass plate G2.

[0073] 13, the sensor unit 11 moves along the path indicated by the arrow B2 so as to pass directly above the support member 6, while repeating reciprocating movement along the width direction X. This allows the distance between the sensor unit 11 and the first main surface Ga of the sample glass plate G2 between two support members 6 adjacent to each other in the width direction X to be measured.

[0074] Thereafter, the sample glass plate G2 is carried out from the mounting unit 2, turned upside down, and carried back into the mounting unit 2. As a result, the sample glass plate G2 is placed on the mounting surface of the mounting unit 2 with the second principal surface Gb as the upper surface and the first principal surface Ga as the lower surface.

[0075] Thereafter, the sample glass plate G2 is supported again by the supporting member 6, and the sensor unit 11 measures the distance between the sensor unit 11 and the second main surface Gb of the sample glass plate G2. The sensor unit 11 transmits the measured data to the communication control unit 18 of the control unit 4.

[0076] 14 and 15 are conceptual diagrams for explaining a method for calculating the deflection difference according to this embodiment. In this method, as shown in FIG. 14, a first deflection d1 is measured when a sample glass plate G2 is supported by a support member 6 with the first main surface Ga facing upward. Then, the sample glass plate G2 is turned upside down, and as shown in FIG. 15, a second deflection d2 is measured when the sample glass plate G2 is supported by a support member 6 with the second main surface Gb facing upward. Then, a difference (|d1-d2|) between the first deflection d1 and the second deflection d2 is calculated, and this is evaluated as a "deflection difference".

[0077] The arithmetic processing unit 16 of the control unit 4 detects the deflection (d1, d2) of the sample glass plate G2 at the intermediate position between two adjacent support members 6 in the width direction X from the measurement data transmitted from the sensor unit 11, and calculates the deflection difference. The control unit 4 causes the memory unit 17 to record the data related to the deflection difference calculated by the arithmetic processing unit 16.

[0078] When measuring the thickness of the sample glass plate G2 in the measurement step S63, the sensor unit 11 of the measurement section 3 irradiates the sample glass plate G2 with laser light L within the range of the groove portion 9 so as not to overlap with the support member 6. That is, as shown in Fig. 16, the sensor unit 11 measures the thickness of the sample glass plate G2 while moving back and forth along the longitudinal direction Y of the base 5 and along the path indicated by the arrow B3.

[0079] The sensor unit 11 of the measurement unit 3 irradiates the first principal surface Ga, which is the upper surface, and the second principal surface Gb, which is the lower surface, of the sample glass plate G2 with laser light L, receives the reflected laser light L, and can measure the plate thickness from the difference in optical path length. In detail, when the plate thickness of the sample glass plate G2 is d [mm], the optical path length difference is L [mm], and the refractive index of the sample glass plate G2 is n, the plate thickness can be measured from d = L / 2n. The sensor unit 11 transmits the measurement data related to the plate thickness to the communication control unit 18 of the control unit 4. After the measurement step S63 is completed, the used sample glass plate G2 is discarded.

[0080] In the evaluation step S64, the evaluation unit 19 of the arithmetic processing unit 16 judges whether the shape of the sample glass plate G2 measured in the measurement step S63 is good or bad.

[0081] Specifically, the evaluation unit 19 compares the measured value of the first warpage amount at each measurement point MP of the sample glass plate G2 in the measurement step S63 with the reference value (reference shape) set for each measurement point MP in the preparation step S61.

[0082] That is, the evaluation unit 19 calculates the difference between the measured value of the first warpage at each measurement point MP of the sample glass plate G2 and the reference value of the first warpage set at each measurement point MP of the reference shape. Next, the evaluation unit 19 determines whether or not this difference is within the range of the threshold value of the first warpage stored in the storage unit 17.

[0083] The evaluation unit 19 judges the sample glass plate G2 as "good" when the difference in the first warpage amount is within a threshold range. The evaluation unit 19 judges the sample glass plate G2 as "no good" when the difference in the first warpage amount is beyond the threshold range.

[0084] In the evaluation process S64, the evaluation unit 19 of the calculation processing unit 16 compares the measured value of the second warpage of the sample glass plate G2 measured in the measurement process S63 with the reference shape to determine whether it is good or bad, in the same manner as in determining the first warpage.

[0085] In the evaluation step S64, the evaluation unit 19 of the calculation processing unit 16 also judges whether the measured values ​​of the deflection difference and plate thickness of the sample glass plate G2 measured in the measurement step S63 are good or bad. Threshold values ​​related to the deflection difference and plate thickness are stored in the memory unit 17 of the control unit 4. The evaluation unit 19 judges whether the measured values ​​of the deflection difference and plate thickness of the sample glass plate G2 are within the range of the threshold. When the measured values ​​of the deflection difference and plate thickness are within the threshold range, the evaluation unit 19 judges the sample glass plate G2 to be "good". When the measured values ​​of the deflection difference and plate thickness exceed the threshold range, the evaluation unit 19 judges the sample glass plate G2 to be "defective".

[0086] If it is found in the evaluation step S64 that the sample glass sheet G2 is defective, that information is transmitted to the forming step S1 or the annealing step S2. In the forming step S1 or the annealing step S2, the forming conditions or the annealing conditions are modified to eliminate the defective shape of the glass ribbon.

[0087] If the sample glass plate G2 is judged to be defective, the glass plates G produced from when the sample glass plate G2 was last judged to be good until when it is judged to be good again are discarded.

[0088] According to the inspection device 1 and the manufacturing method for the glass plate G of this embodiment described above, the shape of the sample glass plate G2 is measured in the measurement step S63 of the inspection process S6 (inspection method), and the measurement result is compared with a reference shape in the evaluation step S64, making it possible to inspect the shape of the sample glass plate G2 with high accuracy even if multiple recesses (groove portions 9) are present on the mounting surface of the mounting portion 2.

[0089] The present invention is not limited to the configuration of the above embodiment, nor is it limited to the above-mentioned effects and advantages. Various modifications of the present invention are possible without departing from the spirit and scope of the present invention.

[0090] In the above embodiment, the mounting surface is inclined at an angle θ with respect to the horizontal direction, but this is not limited thereto. The mounting surface may be configured to be switchable between an inclined state and a state in which the mounting surface coincides with a horizontal plane. Alternatively, the mounting surface may be fixed to coincide with the horizontal plane, and the reference glass plate G1 or the sample glass plate G2 may be positioned by moving the sample glass plate G2 so that the first side GS1 and the second side GS2 of the sample glass plate G2 contact the positioning portions 7a and 7b.

[0091] In the above embodiment, when creating the reference shape, the average value of the multiple measurement data is calculated for each measurement point, but this is not limited to this. It is also possible to calculate the median value of the multiple measurement data, or to calculate the average value after excluding the maximum and minimum values ​​from the multiple measurement data.

[0092] In the above embodiment, the multiple protrusions are formed by the long surface plate 5, but this is not limited thereto. The protrusions may be formed by a lattice-shaped surface plate, and the recesses may be formed by holes between the lattices. Alternatively, the recesses may be formed in a lattice shape, and the surface plate may be disposed between the lattices. [Explanation of symbols]

[0093] 1. Inspection equipment 3 Measuring part 4. Control Unit 5 Surface plate (convex part) 5a Top surface of surface plate (mounting surface) 17 Memory section 19 Evaluation Section G1 Reference Glass Plate G2 Sample glass plate S6 Inspection process S61 Preparation process S62 Calculation process S63 Measurement process S64 Evaluation process W Width of surface plate (width of convex part) D Distance between surfaces (distance between convex parts)

Claims

1. A method for inspecting the shape of a glass plate placed on a placement surface, comprising the steps of: The mounting surface is formed by a plurality of protrusions, The glass plates include a reference glass plate and a sample glass plate; A glass plate inspection method comprising: a measurement step of measuring a shape of the sample glass plate; and an evaluation step of evaluating the shape of the sample glass plate by comparing a reference shape determined by the reference glass plate with a measured value of the shape of the sample glass plate.

2. 2. The glass plate inspection method according to claim 1, further comprising: a preparation step of measuring the shapes of a plurality of the reference glass plates; and a calculation step of calculating the reference shape from measurement values ​​obtained in the preparation step.

3. 3. The glass plate inspection method according to claim 2, wherein in the calculation step, an average value of shapes of a plurality of the reference glass plates is calculated as the reference shape.

4. In the preparation step, a shape of an upper surface of the reference glass plate is measured in a state where the reference glass plate is placed on the placement surface; 4. The glass plate inspection method according to claim 2, wherein in the measuring step, a shape of an upper surface of the sample glass plate is measured in a state in which the sample glass plate is placed on the placement surface.

5. The protrusion is formed of an elongated member, the mounting surface is configured by arranging the elongated members at predetermined intervals, The width of the protrusion is 50 mm or more and 200 mm or less, 4. The glass plate inspection method according to claim 1, wherein the interval between the protrusions is 50 mm or more and 200 mm or less.

6. A method for manufacturing a glass plate, comprising carrying out an inspection step by using the glass plate inspection method according to any one of claims 1 to 3.

7. A glass plate inspection device including a mounting surface on which a glass plate is placed and a measurement unit that measures the shape of the glass plate placed on the mounting surface, The mounting surface is formed of a plurality of protrusions, The glass plates include a reference glass plate and a sample glass plate; A glass plate inspection device comprising: a memory unit that stores a reference shape determined by the reference glass plate; and an evaluation unit that evaluates the shape of the sample glass plate by comparing the shape of the sample glass plate with the reference shape.

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