WO2023100892A1

WO2023100892A1 - Transparent body measuring method and measuring instrument, and method for producing glass plate

Info

Publication number: WO2023100892A1
Application number: PCT/JP2022/044027
Authority: WO
Inventors: 直樹大庭; 忠高橋; 透前田; 裕二徳丸; 智明小柳
Original assignee: 日本電気硝子株式会社
Priority date: 2021-12-03
Filing date: 2022-11-29
Publication date: 2023-06-08

Abstract

This transparent body measuring method includes: a preparation step for placing a transparent body on a placement platform provided with an opening portion; and a measurement step for measuring a property of the transparent body by shining a laser beam from a measuring device through the opening portion onto a glass substrate, while causing the measuring device to move relative to the placement platform in a prescribed measuring direction without stopping.

Description

Measuring method and measuring instrument for transparent body and method for manufacturing glass plate

The present invention relates to a measuring method and measuring instrument capable of measuring the characteristics of transparent bodies including glass plates, and a method of manufacturing a glass plate.

In recent years, panel displays such as liquid crystal display devices and organic EL display devices are becoming larger. In such a display, color unevenness of images becomes a problem. Since the color unevenness of the image is caused by the distortion of the glass substrate used for the display, it is necessary to measure the distortion when manufacturing the glass substrate.

For example, in Patent Document 1, a pedestal, a mounting table that is held by the pedestal and on which a glass substrate is mounted, and a glass substrate that is horizontally supported by the mounting table are irradiated with a laser beam to measure strain. and a measuring unit (glass substrate strain measuring device) is disclosed (see claim 6 of the same document).

In this measuring machine, the pedestal has a slide mechanism that moves the mounting table in the horizontal direction. The mounting table has a plurality of openings for irradiating the glass substrate with laser light emitted from the strain measuring section. The strain measuring unit includes a laser light irradiation unit movable in a direction orthogonal to the moving direction of the mounting table, and a laser light receiving unit arranged to face the laser light irradiation unit and movable in the same direction as the laser light irradiation unit. (See paragraphs 0033, 0041, and 0053 of the same document and FIGS. 1 to 4).

In the method of measuring the strain of a glass substrate using this measuring device, the strain measuring unit irradiates a horizontal glass substrate supported on a mounting table with a laser beam while changing its position along a predetermined direction. . Specifically, the laser light irradiation unit and the laser light reception unit perform various operations such as moving, stopping, and irradiating and receiving laser light with respect to the measurement points of the glass substrate set within the range of each opening of the mounting table. is repeated (see paragraphs 0054 and 0064 of the same document).

WO2017/221825

In the conventional strain measurement method, the strain measurement unit stops and measures the strain every time it moves to the measurement point of the glass substrate set within the range of each opening of the mounting table. In such a measurement method, there is a risk that the measurement time will be prolonged for a glass substrate that is becoming larger.

The present invention has been made in view of the above circumstances, and its technical problem is to efficiently measure the characteristics of transparent bodies including glass plates.

(1) The present invention is intended to solve the above-mentioned problems, and is a method for measuring the characteristics of a transparent body including a glass plate by using a laser transmission type measuring device, comprising: a preparatory step of placing the transparent body; and a measuring step of measuring the characteristics of the transparent body by irradiating a laser beam from a measuring device.

According to such a configuration, in the measurement process, the characteristics of the transparent body are measured while moving the measuring device relative to the mounting table along the predetermined measurement direction without stopping. Measurement time can be shortened compared to the case of stopping the device for measurement. This makes it possible to efficiently measure the properties of the glass substrate.

(2) In the measurement method of (1) above, the measurement device is a birefringence measurement device, and in the preparation step, the transparent body is horizontally placed, and in the measurement step, the birefringence measurement is performed. The property of the transparent body measured by the device may be distortion of the transparent body.

(3) In the measuring method of (2) above, the transparent body may be a glass substrate for a display.

(4) In the measurement method of (2) or (3) above, the birefringence measuring device includes a plurality of birefringence measuring devices, and the plurality of birefringence measuring devices are perpendicular to the measurement direction. They may be spaced apart in the direction. By using a plurality of birefringence measuring devices, the distortion of the transparent body can be measured more efficiently.

(5) In the measuring method according to any one of (1) to (4) above, the opening of the mounting table may be rectangular. As a result, the opening area of the opening formed in the mounting table can be secured as large as possible. Therefore, by securing a wide range in which the transparent body can be irradiated with the laser light, it is possible to acquire more measurement data.

(6) In addition, in the measuring method according to any one of (1) to (5) above, the opening of the mounting table is configured in a rectangular shape, and the long side of the opening extends along the measuring direction. may be formed along the With such a configuration, it is possible to ensure a wide measurement range set on the glass substrate along the measurement direction.

(7) Further, in the measuring method according to any one of the above (1) to (6), the opening of the mounting table includes a plurality of linearly arranged openings, and the measuring step includes: The measuring device may move linearly along the direction in which the plurality of openings are arranged. According to this configuration, by moving the measuring device linearly along the direction in which the plurality of openings are arranged, the transparent body can be efficiently irradiated with the laser beam through each opening located on the straight line. can be done.

(8) In the measurement method of (7) above, the measurement step includes a data detection step of acquiring detection data related to the laser beam that has passed through the glass substrate, and the detection data detected in the data detection step. an arithmetic processing step of calculating the strain by a control device based on the measurement device, wherein the measurement device includes a laser light irradiation unit that emits the laser light and a laser light reception unit that receives the laser light, The mounting table includes a frame portion that partitions the plurality of openings, and in the measuring step, the measuring device applies strain to the transparent body a plurality of times while moving relative to the mounting table. Measurement is performed, and the width dimension of the frame portion positioned between the two adjacent opening portions is determined by the laser beam accompanying the movement of the measuring device during the execution of the arithmetic processing step related to one strain measurement. , and in the measurement step, the laser beam emitted from the laser beam irradiation unit may pass through the frame portion during execution of the arithmetic processing step.

According to such a configuration, the laser light emitted from the measuring device passes through the frame during execution of the arithmetic processing process, thereby ensuring a greater number of strain measurements on the glass substrate within the range of the opening. can be done. This makes it possible to efficiently acquire more measurement data.

(9) In the measuring method according to any one of (1) to (8) above, the relative movement of the measuring device with respect to the mounting table may be the movement of the measuring device.

(10) In the measuring method according to any one of (1) to (8) above, the relative movement of the measuring device with respect to the mounting table may be movement of the mounting table.

(11) The present invention is intended to solve the above problems, and is a method for manufacturing a glass plate, comprising a forming step of forming a glass ribbon from molten glass, and a slow cooling step of slowly cooling the glass ribbon. , a cutting step of cutting the glass ribbon that has undergone the slow cooling step into glass plates of a predetermined size; and an inspection step.

According to this configuration, by efficiently measuring the properties of the glass substrate in the inspection process, changes in the properties of the glass plate can be quickly fed back to the slow cooling process.

(12) The present invention is intended to solve the above-mentioned problems, and is a measuring instrument for measuring the characteristics of a transparent body including a glass plate, comprising: a mounting table for horizontally supporting the transparent body; a laser transmission type measuring device that moves relative to a mounting table, wherein the mounting table has an opening for irradiating a glass substrate with laser light emitted from the measuring device; The characteristics of the transparent body are measured while relatively moving along a predetermined measurement direction with respect to the mounting table without stopping.

According to this configuration, by measuring the properties of the transparent body while relatively moving along the predetermined measurement direction without stopping the measuring apparatus with respect to the mounting table, the measuring apparatus can be stopped as in the conventional art. Measurement time can be shortened compared to the case of measuring by This makes it possible to efficiently measure the properties of the glass substrate.

(13) In the measuring machine of (12) above, the opening of the mounting table may be configured in a rectangular shape. As a result, the opening area of the opening formed in the mounting table can be secured as large as possible.

According to the present invention, the properties of transparent bodies including glass plates can be efficiently measured.

It is a side view of a measuring machine. It is a side view of a measuring machine. It is a top view of a measuring machine. It is a front view of a measuring machine. It is a top view which shows the measuring method of a transparent body. It is a top view which shows the measuring method of a transparent body. It is a top view which shows the measuring method of a transparent body. It is a top view which shows the measuring method of a transparent body. FIG. 10 is a plan view showing another example of the mounting table in the measuring machine;

Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. FIGS. 1 to 9 show an embodiment of the transparent body measuring method and measuring apparatus according to the present invention. In the XYZ orthogonal coordinate system shown in FIGS. 1 to 9, the X-axis direction and the Y-axis direction indicate the horizontal direction, and the Z-axis direction indicates the vertical direction (vertical direction).

The measuring method and measuring instrument according to the present invention are for measuring the properties of transparent bodies including glass plates. Properties of the transparent body include, for example, thickness, surface roughness, waviness, distortion, and the like. Examples of transparent bodies include a transparent glass plate, a glass plate laminate obtained by laminating a plurality of transparent glass plates via a transparent adhesive, and a transparent adhesive between a transparent glass plate and a transparent resin. Examples thereof include a glass resin laminate formed by laminating via a material.

In this embodiment, a case of measuring distortion of a transparent glass substrate for display will be described as an example. The glass substrate is formed in a square or rectangular shape, for example, and the size of one side thereof is, for example, 2000 to 3400 mm. The thickness of the glass substrate is, for example, 0.1 to 1.2 mm. The shape, dimensions, thickness, and the like of the glass substrate are not particularly limited, and can be appropriately changed according to the application.

As shown in FIGS. 1 to 4, the measuring instrument 1 includes a pedestal 2, a mounting table 3 capable of horizontally supporting a glass substrate G, and a A relatively movable laser transmission type measuring device 4 and a control device 5 for controlling operations of the mounting table 3 and the measuring device 4 are provided.

The mount 2 is a stand for holding the mounting table 3 in an inclined state or a horizontal state, and is installed on the floor surface. Here, the “horizontal state” is not limited to a completely horizontal state (tilt angle=0°), but also includes a substantially horizontal state, for example, a visually horizontal state. Specifically, the “horizontal state” means that the tilt angle with respect to the horizontal direction (Y-axis direction) is −10° or more and less than 0°, or more than 0° and 10° when the mounting table 3 is slightly tilted. It also includes states that are in the following range.

As shown in FIGS. 1 to 3, the gantry 2 is elongated along the Y-axis direction. The gantry 2 includes a slide mechanism 6 that moves the mounting table 3 along its longitudinal direction. The slide mechanisms 6 are arranged at both ends of the mounting table 3 in the width direction (X-axis direction).

Each slide mechanism 6 includes a rotating shaft 7 that rotatably supports the intermediate portion of the mounting table 3 , a horizontal driving device (not shown) that moves the mounting table 3 along the horizontal direction, and a rotating shaft 7 . and a rotation drive device (not shown) for rotating the mounting table 3 around the .

The horizontal drive device is composed of, for example, an LM guide (registered trademark), a ball screw mechanism, a linear motion mechanism equipped with a motor, etc. By operating the horizontal drive device, the mounting table 3 in a horizontal state can be moved along the longitudinal direction (Y-axis direction) of the gantry 2 .

The rotation drive device is composed of an actuator such as an air cylinder or a motor. The rotary drive device can change the mounting table 3 between, for example, an inclined state having an angle of 70 to 80 degrees with respect to the horizontal direction (Y-axis direction) and a horizontal state via the rotary shaft 7. can.

As shown in FIG. 3, the mounting table 3 includes a stage portion 8, a receiving portion 9, and

positioning portions

10a and 10b.

The stage part 8 is configured by a plate-shaped member made of metal (eg, made of aluminum). The stage portion 8 functions as a surface plate for maintaining the flatness of the glass substrate G at a desired accuracy when strain is measured.

The stage part 8 has a mounting surface configured as a flat surface. The mounting surface includes a plurality of openings 11 and

frame portions

12 a and 12 b that separate the openings 11 .

Each opening 11 is configured, for example, in a square shape, but is not limited to this shape. Each opening 11 is for irradiating the glass substrate G with a laser beam emitted upward from below the mounting table 3 when strain measurement is performed by the measuring device 4 . The plurality of openings 11 are linearly arranged at predetermined intervals along the X-axis direction and the Y-axis direction of the stage portion 8 .

As shown in FIG. 3 , the

frame portions

12 a and 12 b support one surface of the glass substrate G when the glass substrate G is placed on the stage portion 8 . Each of the

frame portions

12a and 12b has a predetermined length dimension and width dimension, and is configured linearly.

The

frame portions

12a and 12b include a first frame portion 12a along the X-axis direction and a second frame portion 12b along the Y-axis direction. By forming the first frame portion 12a and the second frame portion 12b to be perpendicular to each other, the opening portion 11 has a rectangular shape. Moreover, the mounting surface of the stage section 8 is configured in a grid pattern by connecting the plurality of first frame portions 12a and the second frame portions 12b so as to be orthogonal to each other.

As shown in FIGS. 1 to 3 , the receiving portion 9 is provided on one end side of the stage portion 8 and is elongated along the width direction of the mounting table 3 . The receiving portion 9 supports one end portion (lower end portion) of the glass substrate G when the mounting table 3 is in an inclined state. Further, the receiving portion 9 functions as a positioning portion that contacts one end portion of the glass substrate G when the mounting table 3 is in a horizontal state. The receiving part 9 is configured so that its position can be changed so that it can be positioned according to the size of the glass substrate G. As shown in FIG.

As shown in FIG. 3, the

positioning portions

10a and 10b include a pair of first positioning portions 10a for positioning each end portion of the glass substrate G in the X-axis direction when the mounting table 3 is in a horizontal state, and a second positioning portion 10b that positions the end portion of the glass substrate G in the direction (the end portion opposite to the end portion that contacts the receiving portion 9). Each

positioning part

10a, 10b is configured so that the position can be changed so that the positioning can be performed according to the size of the glass substrate G. As shown in FIG.

The measuring device 4 is arranged in the middle of the gantry 2 in the longitudinal direction. The measurement device 4 includes a laser beam irradiation unit 13, a laser beam receiving unit 14, a support member 15 for supporting the laser beam receiving unit 14, a driving device (not shown) for driving the laser beam irradiation unit 13, and a laser beam. and a driving device (not shown) that drives the light receiving unit 14 .

The laser beam irradiation unit 13 is provided below the pedestal 2 and configured to emit a laser beam upward from below the mounting table 3 toward the opening 11 . Also, the laser beam irradiation unit 13 is configured to be moved along the X-axis direction by a driving device.

The laser light receiving section 14 is positioned above the laser light irradiation section 13 so as to face the laser light irradiation section 13 in the vertical direction (Z-axis direction). The laser light receiving section 14 is configured to be moved along the X-axis direction by a driving device.

Due to the positional relationship between the laser beam irradiation unit 13 and the laser beam receiving unit 14 as described above, when the mounting table 3 is in a horizontal state, the laser beam irradiation unit 13 and the laser beam receiving unit 13 are positioned vertically (in the Z-axis direction). It will be located between 14.

The support member 15 supports the laser light receiving section 14 so as to be movable in the X-axis direction. Further, the support member 15 supports a driving device that drives the laser light receiving section 14 .

The drive device for the laser light irradiation unit 13 and the drive device for the laser light reception unit 14 are configured by, for example, a linear motion mechanism including an LM guide (registered trademark), a ball screw mechanism, a motor, and the like.

The measurement device 4 may be configured to move the laser light irradiation unit 13 and the laser light reception unit 14 in the X-axis direction and the Y-axis direction by combining a plurality of driving devices without being limited to the above configuration. . Moreover, the measuring device 4 may have a configuration in which the laser beam irradiation unit 13 and the laser beam receiving unit 14 are attached to a robot arm (driving device). Thereby, the measuring device 4 can three-dimensionally move the laser beam irradiation unit 13 and the laser beam receiving unit 14 .

As the measuring device 4, for example, a birefringence measuring device that measures the birefringence amount of the glass substrate G using a common optical path interferometer and a Fourier analysis method by an optical heterodyne method is preferably used. This birefringence measuring apparatus can measure the magnitude of retardation (retardation: phase difference due to birefringence) and the azimuth angle of the retardation in order to evaluate the degree of distortion of the glass substrate G. FIG. In addition, it means that distortion is so large that retardation is large.

The control device 5 controls the operation of the drive device (horizontal drive device, rotation drive device) of the slide mechanism 6 of the pedestal 2, the operation of the drive device of the measurement device 4, and the measurement device 4 (laser beam irradiation unit) related to strain measurement. 13 and laser light receiving unit 14).

The control device 5 is, for example, a personal computer (PC) equipped with a processing device such as a CPU, a storage device such as a memory, and a display device such as a display. The control device 5 can output measurement results and the like of the glass substrate G to the display device. In addition, the control device 5 can store data such as measurement results of the glass substrate G in the storage device.

A method of measuring the strain, which is a characteristic of the glass substrate G, and a method of manufacturing the glass substrate G using the measuring instrument 1 configured as described above will be described below. This measurement method is used, for example, to measure the strain of the glass substrate G in the manufacturing process of the glass substrate G, and to feed back information regarding the quality of the glass substrate G to the manufacturing process based on the measurement results.

The method for manufacturing the glass substrate G includes a forming step of drawing molten glass in a predetermined direction to form a plate-shaped glass ribbon, a slow cooling step of slowly cooling the glass ribbon formed in the forming step, and a slow cooling step. The method includes a cutting step of cutting the slowly cooled glass ribbon into a predetermined size to obtain a glass plate, and an inspection step of applying the present measurement method to the glass plate obtained in the cutting step.

In the slow cooling process, the glass ribbon flows down inside the slow cooling furnace, which prevents unintended thermal strain from occurring in the glass ribbon. The slow cooling furnace is equipped with a plurality of heaters in the drawing direction and width direction of the glass ribbon, and is adjusted to a predetermined temperature gradient. The distortion of the glass sheet can be reduced by controlling the output of the heater in the annealing furnace and adjusting the temperature gradient in the annealing furnace based on the distortion of the glass sheet measured by this measuring method.

This measurement method includes a preparation step of mounting the glass substrate G on the mounting table 3 and a measurement step of measuring the distortion of the glass substrate G mounted on the mounting table 3 .

As shown in FIG. 1, in the preparation process, the glass substrate G is placed on the mounting table 3 that stands by in an inclined state on one end side of the pedestal 2 . Specifically, for example, an operator holds the glass substrate G using a suction holder such as a vacuum lift, and then places the glass substrate G on the mounting table 3 . As a result, the glass substrate G is supported in an inclined manner with its lower end in contact with the receiving portion 9 of the mounting table 3 .

After that, as shown in FIG. 2 , the control device 5 operates the rotation drive device of the slide mechanism 6 to rotate the mounting table 3 around the rotation shaft 7 . As a result, the posture of the mounting table 3 is changed from the inclined state to the horizontal state, and the glass substrate G is horizontally supported by the mounting table 3 .

In the measurement process, the measuring machine 1 measures the glass substrate G by relatively moving the mounting table 3 and the measuring device 4 under the control of the control device 5 . The relative movement modes of the mounting table 3 and the measuring device 4 are a first movement mode in which the laser light irradiation unit 13 and the laser light receiving unit 14 are moved while the mounting table 3 is stopped; and a second movement mode in which the mounting table 3 is moved while the laser light receiving unit 14 is stopped.

The measurement process based on the first movement mode and the second movement mode will be described below with reference to FIGS. 5 to 7. FIG. 5 to 7 are plan views showing the glass substrate G mounted on the stage portion 8 of the mounting table 3 in a horizontal state. 5 and 6 show the measurement process based on the first movement mode, and FIG. 7 shows the measurement process based on the second movement mode.

In the example shown in FIGS. 5 and 6, among the plurality of openings 11 formed in the stage portion 8 of the mounting table 3, the first row M1 arranged along the X-axis direction (measurement directions X1, X2), A case of measuring the glass substrate G with respect to the openings 11 belonging to the second row M2 and the third row M3 will be described.

Under the control of the control device 5, the laser beam irradiation unit 13 and the laser beam receiving unit 14 move in the measurement direction X1 from the position corresponding to the first opening 11S in the first row M1 to the position corresponding to the last opening 11E. move along. In this case, the laser beam irradiation unit 13 and the laser beam receiving unit 14 move (continuously) at a constant speed without stopping until reaching the position corresponding to the last opening 11E of the first row M1. . While the laser beam irradiation unit 13 and the laser beam receiving unit 14 are moving, the mounting table 3 is in a stopped state (hereinafter, the same applies to measurements of the second row M2 and the third row M3).

With the movement of the laser light irradiation unit 13 and the laser light receiving unit 14 as described above, the laser light emitted from the laser light irradiation unit 13 is, in a plan view shown in FIG. It moves so as to pass through the

openings

11S, 11, 11E and the second frame portion 12b associated with the row M1 along the measurement direction X1. As a result, the laser light moves relative to the glass substrate G and linearly. The moving speed of the laser beam, that is, the moving speed of the laser beam irradiation unit 13 and the laser beam receiving unit 14 is, for example, 10 to 1000 mm/s, preferably 50 to 200 mm/s.

The laser beam irradiates the glass substrate G through each opening 11 while moving as described above. The laser light applied to the glass substrate G through the opening 11 reaches the laser light receiving section 14 after passing through the glass substrate G. As shown in FIG. The control device 5 calculates the distortion of the glass substrate G based on the detection data regarding the birefringence amount of the laser light detected by the laser light receiving section 14 .

When the measurement of the glass substrates G corresponding to all the openings 11 belonging to the first row M1 is completed, the measurement of the glass substrates G corresponding to the openings 11 belonging to the second row M2 is performed. When the laser beam reaches the last opening 11E of the first row M1, the control device 5 stops the laser beam irradiation unit 13 and the laser beam receiving unit 14, and moves the mounting table 3 in the direction Y2 perpendicular to the measurement direction X1. move along.

As a result, the laser light is distributed relative to the glass substrate G from the position of the last opening 11E in the first row M1 to the position of the first opening 11S in the second row M2, as indicated by the arrow A2. , and move in a straight line. At this time, the laser light passes through the first frame portion 12a that separates the last opening 11E in the first row M1 and the first opening 11S in the second row M2.

After that, the control device 5 stops the mounting table 3 and moves the laser beam irradiation unit 13 and the laser beam receiving unit 14 along the measurement direction X2. As a result, as indicated by an arrow A3, the laser light travels relatively and linearly with respect to the glass substrate G from the position of the first opening 11S to the position of the last opening 11E in the second row M2. Moving.

Due to this movement, the glass substrate G is irradiated with laser light through each opening 11 , and the laser light that has passed through the glass substrate G is received by the laser light receiving section 14 . The control device 5 calculates the distortion of the glass substrate G based on the detection data regarding the birefringence amount of the laser light detected by the laser light receiving section 14 in the same manner as the measurement at the openings 11 of the first row M1.

When the measurement of the glass substrates G corresponding to all the openings 11 belonging to the second row M2 is completed, the measurement of the glass substrates G corresponding to the openings 11 belonging to the third row M3 is performed. When the laser beam reaches the last opening 11E of the second row M2, the control device 5 stops the laser beam irradiation unit 13 and the laser beam receiving unit 14, and moves the mounting table 3 in the direction Y2 perpendicular to the measurement direction X2. move along.

As a result, the laser light is distributed relative to the glass substrate G from the position of the last opening 11E in the second row M2 to the position of the first opening 11S in the third row M3, as indicated by an arrow A4. , and move in a straight line. At this time, the laser light passes through the first frame portion 12a that separates the last opening 11E in the second row M2 and the first opening 11S in the third row M3.

After that, the control device 5 stops the mounting table 3 and moves the laser beam irradiation unit 13 and the laser beam receiving unit 14 along the measurement direction X1. As a result, as indicated by an arrow A5, the laser light travels from the position of the first opening 11S to the position of the last opening 11E in the third row M3 relatively and linearly with respect to the glass substrate G. Moving. During the movement of the laser light, strain measurement similar to the measurement of the glass substrate G corresponding to the openings 11 of the first row M1 and the second row M2 is performed. After that, the above operation is repeated from the fourth row to the last row to complete the measurement of the entire glass substrate G. FIG.

In the above measurement process, while the laser light passes through one opening 11 along the measurement directions X1 and X2, the glass substrate G is distorted once or multiple times within the range of the opening 11. can be measured.

In a single measurement of strain, the measurement process includes a data detection process of obtaining detection data on the birefringence amount of the laser light by the laser light receiving unit 14, and a control device based on the detection data detected in the data detection process. and an arithmetic processing step of calculating the strain. The time required for one strain measurement is the sum of the data detection time required for the data detection step and the arithmetic processing time required for the arithmetic processing step. In this embodiment, it is desirable that the time required for each strain measurement by the measuring device 4 is 0.1 second or less.

In this embodiment, by alternately repeating the data detection process and the arithmetic processing process in the measurement process, it is possible to measure the distortion of the glass substrate G multiple times within the range of one opening 11 . The case of performing this measurement will be described below with reference to FIG. FIG. 6 shows an enlarged state in which the laser light moves in the direction indicated by the arrow A5 with respect to the openings 11 belonging to the third row M3 illustrated in FIG.

The measuring device 4 is set to perform three measurements in one opening 11 belonging to the third row M3. Three measurement areas, a first measurement area MA1, a second measurement area MA2 and a third measurement area MA3, are set within the range of one opening 11 on the glass substrate G placed on the stage part 8. It is Each of the measurement areas MA1-MA3 is configured linearly along the measurement direction X1.

The laser beam irradiation unit 13 irradiates the first measurement area MA1 with laser beams while moving along the measurement direction X1 together with the laser beam receiving unit 14 . The laser light passes through this first measurement area MA1 and reaches the laser light receiving section 14 .

The time during which the first measurement area MA1 is irradiated with the moving laser light corresponds to the data detection time in the data detection process. The travel time (data detection time) of this laser beam is, for example, 0.05 seconds. While this time elapses, the laser light moves by the length of the first measurement area MA1, that is, the distance (first movement distance) indicated by symbol D1 in FIG.

The control device 5 executes the arithmetic processing process while the laser beam moves from the end of the first measurement area MA1 to the beginning of the second measurement area MA2. That is, the control device 5 calculates the strain in the first measurement area MA1 based on the detection data of the laser light detected through the laser light receiving section 14. FIG. The time taken for the laser light to move from the first measurement area MA1 to the second measurement area MA2 corresponds to the arithmetic processing time in the arithmetic processing step. In this case, the movement time (calculation processing time) of the laser light is, for example, 0.05 seconds. While this time elapses, the laser beam moves by a distance (second movement distance) indicated by symbol D2 in FIG. In this embodiment, the second moving distance D2 is equal to the first moving distance D1, but these distances D1 and D2 may be different.

The measurement of strain in the first measurement area MA1, that is, the time required for the first measurement (measurement time) is, for example, 0.1 seconds, which is the sum of the data detection time and the arithmetic processing time. Further, the moving distance of the laser beam (relative moving distance of the measuring device 4) in the first measurement is the sum of the first moving distance D1 and the second moving distance D2 (D1+D2). That is, in the measurement process of the present embodiment, the data detection process and the arithmetic processing process performed while the laser beam moves this distance (D1+D2) are regarded as one cycle, and laser beams are applied to each measurement area set at an equal pitch (D2). The glass substrate G is measured while being irradiated with light. Note that the moving distance (D1+D2) of the laser light is, for example, 5 to 10 mm, but is not limited to this range.

When the first measurement is completed, the second measurement will be performed. In the second measurement, the second measurement area MA2 is irradiated with the laser beam emitted from the laser beam irradiation unit 13 as the measurement device 4 is continuously moved. During this time, the laser light that has passed through the second measurement area MA2 is received by the laser light receiving unit 14, and detection data related to the laser light is detected (data detection step).

After that, while the laser beam moves from the end of the second measurement area MA2 to the beginning of the third measurement area MA3, the control device 5 calculates the distortion of the second measurement area MA2 (computation processing step ). The data detection time and distortion calculation processing time in the second measurement are the same as in the first measurement. In the second measurement, the distance traveled by the measuring device 4 and the laser light is the same as the travel distance (D1+D2) in the first measurement.

The third measurement will be done in the same way as the first and second measurements. The measurement device 4 irradiates the third measurement area MA3 with laser light while moving along the measurement direction X1. During this time, the laser light that has passed through the third measurement area MA3 is received by the laser light receiving unit 14, and detection data related to the laser light is detected (data detection step). Based on this detection data, the control device 5 calculates the strain associated with the third measurement area MA3 (calculation processing step).

The opening 11 has an opening area that allows multiple measurements by the measuring device 4 as described above. That is, the interval W1 between the pair of second frame portions 12b that separate one opening 11 is greater than the distance (D1+D2) that the laser beam and the measuring device 4 move in one measurement (W1>(D1+D2)).

Of the plurality of measurements performed on the glass substrate G within the range of one opening 11, the final measurement (the third measurement in the above example) is during execution of the arithmetic processing process by the control device 5. In addition, it is desirable that the laser light passes through the second frame portion 12b that separates the opening 11 and the next opening 11 . Thereby, measurement of the glass substrate G can be started immediately after the laser light reaches the next opening 11 . Therefore, it is possible to secure as many strain measurements as possible within the range of one opening 11 .

In this case, as shown in FIG. 6, the width dimension W2 of the second frame portion 12b positioned between the two openings 11 adjacent in the measurement direction X1 is determined by the laser beam and the It is preferably set smaller than the second moving distance D2 that the measuring device 4 moves (W2<D2).

When the arithmetic processing process is completed, the control device 5 outputs the measurement result (distortion calculation result) of the glass substrate G to the display device. Further, the control device 5 saves the data of the measurement result of the glass substrate G in the storage device. In addition, the control device 5 compares the measurement results with standard values (magnitude of retardation and azimuth angle of retardation), which are preset indices for evaluating distortion, and judges whether the distortion in the glass substrate G is good or bad. can be done. The control device 5 causes the display device to display the determination result.

FIG. 7 shows the measurement process according to the second movement mode. In this example, among the plurality of openings 11 formed in the stage portion 8 of the mounting table 3, a first row N1, a second row N2 and a A case of measuring the glass substrate G according to the openings 11 belonging to the third row N3 will be described.

The control device 5 arranges the laser beam irradiation unit 13 and the laser beam receiving unit 14 of the measurement device 4 at positions corresponding to the first opening 11S of the first row N1. After that, the control device 5 causes the laser light irradiation section 13 to emit laser light while the laser light irradiation section 13 and the laser light receiving section 14 are stopped.

After that, the control device 5 moves the mounting table 3 linearly at a constant speed along the measurement direction Y1 with respect to the stopped laser beam irradiation unit 13 and laser beam receiving unit 14 . As a result, as indicated by an arrow B1, the laser light travels relatively and linearly with respect to the glass substrate G from the position of the first opening 11S to the position of the last opening 11E in the first row N1. Moving.

The measurement device 4 and the control device 5 move the mounting table 3 in the Y1 direction to move the laser light relative to the mounting table 3, and move the laser beams relative to the mounting table 3. Similarly, the data detection process and the arithmetic processing process are repeated.

When the measurement of the glass substrate G within the range of the last opening 11E of the first row N1 is completed, the control device 5 stops the mounting table 3 and moves the laser beam irradiation unit 13 and the laser beam receiving unit 14 in the measurement direction. It is moved along the direction X1 orthogonal to Y1. As a result, the laser light travels from the position of the last opening 11E in the first row N1 to the position of the first opening 11S in the second row N2 relative to the glass substrate G, as indicated by an arrow B2. , and move in a straight line.

After that, the control device 5 stops the laser beam irradiation unit 13 and the laser beam receiving unit 14, and moves the mounting table 3 along the measurement direction Y2. As a result, as indicated by an arrow B3, the laser light travels from the position of the first opening 11S to the position of the last opening 11E in the second row N2 relatively and linearly with respect to the glass substrate G. Moving.

When the measurement of the glass substrate G within the range of the last opening 11E in the second row N2 is completed, the control device 5 stops the mounting table 3 and moves the laser beam irradiation unit 13 and the laser beam receiving unit 14 in the measurement direction. It is moved along the direction X1 orthogonal to Y2. As a result, the laser light is distributed relative to the glass substrate G from the position of the last opening 11E in the second row N2 to the position of the first opening 11S in the third row N3, as indicated by an arrow B4. , and move in a straight line.

After that, the control device 5 stops the laser beam irradiation unit 13 and the laser beam receiving unit 14, and moves the mounting table 3 along the measurement direction Y1. As a result, as indicated by an arrow B5, the laser light travels from the position of the first opening 11S to the position of the last opening 11E in the third row N3 relatively and linearly with respect to the glass substrate G. Moving.

Also in the measurement process based on the second movement mode described above, it is possible to measure the strain on the glass substrate G multiple times within the range of one opening 11, as in the example of FIG.

FIG. 8 shows another example of the measurement process. In this example of the measurement process, the measurement of the glass substrate G is performed by repeating the movement of the laser light a plurality of times within the range of the plurality of openings 11 arranged in a row. In this example, measurements based on the first movement mode will be described, but measurements based on the second movement mode can also be performed.

Specifically, in this measurement step, the movement of the measuring device 4 in the first movement mode is repeated three times with respect to the plurality of openings 11 arranged in the third row M3, so that the laser light is moved from arrows C1 to Repeat the linear movement three times, as indicated by C3.

In the first movement, the control device 5 causes the laser beam irradiation unit 13 to emit a laser beam while the mounting table 3 is stopped, and moves the laser beam irradiation unit 13 and the laser beam receiving unit 14 in the measurement direction X1. move along. Thereby, the laser light moves relatively and linearly with respect to the glass substrate G, as indicated by an arrow C1. Thereby, the distortion of the glass substrate G is measured through the plurality of openings 11 belonging to the third row M3.

After the first movement is completed, the control device 5 moves the mounting table 3 along the direction Y2 orthogonal to the measurement direction X1 in order to change the irradiation position of the laser light on the glass substrate G. In this case, the laser light changes its position in the Y-axis direction within the range of the openings 11 belonging to the same third row M3 through which it passed by the first movement.

In the second movement, the control device 5 stops the mounting table 3 and linearly moves the laser beam irradiation unit 13 and the laser beam receiving unit 14 along the measurement direction X2. Thereby, the laser light moves relatively and linearly with respect to the glass substrate G so as to pass through the plurality of openings 11 belonging to the third row M3, as indicated by the arrow C2.

When the second movement is completed, the control device 5 moves the mounting table 3 along the direction Y2 perpendicular to the measurement direction X2. In this case, the laser light changes its position in the Y-axis direction within the range of the openings 11 belonging to the same third row M3 passed by the second movement.

In the third movement, the control device 5 stops the mounting table 3 and moves the laser beam irradiation unit 13 and the laser beam receiving unit 14 along the measurement direction X1. Thereby, the laser light moves relatively and linearly with respect to the glass substrate G so as to pass through the plurality of openings 11 belonging to the third row M3, as indicated by the arrow C3.

As described above, a larger number of measurement data can be acquired by reciprocating the laser light multiple times within the range of the multiple openings 11 located in the same row. For such measurements, it is better to configure the opening 11 in a rectangular shape rather than in a circular shape. By configuring the opening 11 in a rectangular shape, the opening area is increased compared to the case of configuring in a circular shape (indicated by a two-dot chain line in FIG. 8), and the measurement range for the glass substrate G is widened as much as possible. can be secured.

FIG. 9 shows another example of the mounting table 3 (stage section 8) in the measuring machine 1. FIG. In this example, the opening 11 of the stage section 8 is configured in a rectangular shape. A long side 11a of the opening 11 is formed along the measurement directions Y1 and Y2 with respect to the Y-axis direction. In other words, the length dimension in the Y-axis direction of the second frame portion 12b of the stage portion 8 is larger than the length dimension in the X-axis direction of the first frame portion 12a.

With the above configuration, more measurement areas can be set on the glass substrate G within the range of each opening 11 when moving the laser light along the measurement directions Y1 and Y2. This makes it possible to acquire more measurement data.

Not limited to this example, when the laser light is moved along the measurement directions X1 and X2 related to the X-axis direction, the long sides of the opening 11 may be formed along the measurement directions X1 and X2. .

It should be noted that the present invention is not limited to the configuration of the above-described embodiment, nor is it limited to the above-described effects. Various modifications can be made to the present invention without departing from the gist of the present invention.

In the above embodiment, the laser beam irradiation unit 13 is provided at the bottom of the pedestal 2 and the laser beam receiving unit 14 is provided at the top of the pedestal 2, but the present invention is not limited to this configuration. The laser beam irradiation unit 13 may be provided on the upper part of the pedestal 2 and the laser beam receiving part 14 may be provided on the lower part of the pedestal 2 .

In the present embodiment, the glass substrate G is irradiated with laser light even while the arithmetic processing step is being executed, but the present invention is not limited to this configuration. The irradiation of the laser beam to the glass substrate G may be stopped while the arithmetic processing step is being performed.

In the above embodiment, the measuring device 4 having one laser beam irradiation unit 13 and one laser beam receiving unit 14 was exemplified, but the present invention is not limited to this configuration. The measuring device 4 may include a plurality of laser beam irradiation units 13 and laser beam receiving units 14 . In this case, the plurality of laser light emitting units 13 and laser light receiving units 14 can be arranged at intervals in directions Y1 and Y2 perpendicular to the measurement directions X1 and X2 in relation to the X-axis direction, for example. According to this configuration, the measuring device 4 can shorten the measurement time as much as possible compared to the case where the measuring device 4 is provided with one laser beam irradiation unit 13 and one laser beam receiving unit 14 .

In the above embodiment, the birefringence measuring device was exemplified as the measuring device 4 of the measuring instrument 1, but the present invention is not limited to this configuration. A laser transmission type measuring device other than the birefringence measuring device may be applied to the present invention.

Reference Signs List 1 measuring machine 3 mounting table 4 measuring device 11 opening 11a long side 12a of opening first frame 12b second frame 13 laser beam irradiation unit 14 laser beam receiving unit G glass substrate (transparent body)
X1 measurement direction X2 measurement direction Y1 measurement direction Y2 measurement direction

Claims

A method for measuring properties of a transparent body including a glass plate with a laser transmission type measuring device,
a preparation step of mounting the transparent body on a mounting table having an opening;
By irradiating the transparent body with a laser beam from the measuring device through the opening while moving the measuring device relative to the mounting table along a predetermined measurement direction without stopping, and a measuring step of measuring the properties of the transparent body.
The measuring device is a birefringence measuring device,
In the preparation step, the transparent body is placed horizontally,
2. The method of measuring a transparent body according to claim 1, wherein in the measuring step, the characteristic of the transparent body measured by the birefringence measuring device is distortion of the transparent body.
The method for measuring a transparent body according to claim 2, wherein the transparent body is a glass substrate for a display.
The birefringence measurement device includes a plurality of birefringence measurement devices,
4. The method of measuring a transparent body according to claim 2, wherein the plurality of birefringence measuring devices are arranged at intervals in a direction orthogonal to the measuring direction.
The transparent body measuring method according to any one of claims 1 to 3, wherein the opening of the mounting table is configured in a rectangular shape.
The opening of the mounting table is configured in a rectangular shape,
The method of measuring a transparent body according to any one of claims 1 to 3, wherein the long sides of the opening are formed along the measurement direction.
the opening of the mounting table includes a plurality of linearly arranged openings,
4. The transparent body measuring method according to claim 1, wherein in the measuring step, the measuring device moves linearly along the direction in which the plurality of openings are arranged.
The measurement step includes a data detection step of acquiring detection data related to the laser beam that has passed through the transparent body, and an arithmetic processing of calculating the strain by a control device based on the detection data detected in the data detection step. comprising a process and
The measuring device includes a laser light irradiation unit that emits the laser light and a laser light receiving unit that receives the laser light,
The mounting table includes a frame section that separates the plurality of openings,
In the measuring step, the measuring device measures the characteristics of the transparent body a plurality of times while moving relative to the mounting table;
The width dimension of the frame positioned between the two adjacent openings is the moving distance of the laser beam accompanying the movement of the measuring device during execution of the arithmetic processing step relating to one measurement of the characteristics. is set smaller than
8. The method of measuring a transparent body according to claim 7, wherein in the measuring step, the laser beam emitted from the laser beam irradiation unit passes through the frame portion during execution of the arithmetic processing step.
The method for measuring a transparent body according to any one of claims 1 to 3, wherein the relative movement of the measuring device with respect to the mounting table is movement of the measuring device.
The method for measuring a transparent body according to any one of claims 1 to 3, wherein the relative movement of the measuring device with respect to the mounting table is movement of the mounting table.
A forming step of forming a glass ribbon from molten glass, a slow cooling step of slowly cooling the glass ribbon, a cutting step of cutting the glass ribbon that has undergone the slow cooling step into glass plates of a predetermined size, and for the glass plate and an inspection step of performing the method for measuring a transparent body according to any one of claims 1 to 3.
A measuring instrument for measuring properties of a transparent body including a glass plate,
A mounting table that horizontally supports the transparent body, and a laser transmission type measuring device that moves relative to the mounting table,
The mounting table has an opening for irradiating the glass substrate with laser light emitted from the measuring device,
A measuring instrument for measuring a transparent body, wherein the measuring device measures the properties of the transparent body while moving relative to the mounting table along a predetermined measuring direction without stopping the measuring device.
The transparent body measuring machine according to claim 12, wherein the opening of the mounting table is configured in a rectangular shape.