JP6410208B2 - Shape measuring device - Google Patents

Description

  The present invention relates to a shape measuring apparatus that measures a surface shape of a plate-like body using a fluid floating portion that discharges fluid to float the plate-like body as a constituent element.

  In recent years, in flat panel displays (hereinafter referred to as FPD) such as liquid crystal displays, plasma displays, and organic EL displays, lighting panels, and solar cell panels, the use of lightweight and flexible thin glass substrates has become increasingly popular. Has been promoted. Light and flexible plate-like bodies typified by this type of glass substrate are required to have high flatness, but because of deformation such as warpage and swell due to temperature changes during production, the quality From the viewpoint of management and the like, the necessity of measuring the original surface shape of the plate-like body has been emphasized.

  An apparatus for measuring the surface shape of this type of plate-like body is a surface shape from the surface side of the plate-like body using a measuring instrument or the like while the plate-like body is placed on a surface plate and is stationary. It was common to be configured to measure. However, in such a general apparatus, since the plate-like body is pressed onto the surface plate by its own weight, it is difficult to accurately measure the original surface shape of the plate-like body.

  As an apparatus mainly intended to solve such a problem, according to Patent Document 1, air is discharged from a plurality of air ejection nozzles formed over the entire surface of a single fixed plate, and the plate-like body is fixed to the fixed plate. After levitation, the air discharge is released and the plate-like body is dropped freely. During the free fall, the surface shape of the plate-like body is measured by means of measuring means (spatial coordinate detecting means in Patent Document 1). A configuration for measuring is disclosed.

Japanese Patent Laid-Open No. 10-068620

  However, even with the apparatus disclosed in Patent Document 1, when the plate-like body has a characteristic of easily deforming like a thin plate glass or glass film, various problems as shown below are caused. Had.

  That is, since this apparatus is configured to measure the surface shape of the plate-like body in the middle of free fall, the plate-like body is deformed by the air resistance at the time of dropping, and the original surface shape is measured. It was difficult or impossible. Also, since the measuring means must measure the surface in a short time during the fall of the plate-like body, it becomes necessary to provide a plurality of measuring means. There was a problem of inviting.

  Furthermore, since this apparatus is a structure which measures a surface shape in the state which discharged the air from the several air ejection nozzle arrange | positioned over the whole surface area of the single fixed plate, and floated the plate-shaped body, The distribution of the pressure of the air acting on the surface of the plate-like body is not a preferable mode, and has been a great hindrance in measuring an accurate surface shape. More specifically, the air jetted near the center of the plate-like body is prevented from flowing out from the lower space of the plate-like body to the outside by the air jetted near the edge of the plate-like body. In such a state, when air is blown one after another into the lower space of the plate-like body, the pressure of the air acting on the central portion of the plate-like body becomes the pressure of the air acting on the vicinity of the edge of the plate-like body. Therefore, the central portion of the plate-like body is curved and deformed so as to be convex upward. Therefore, even if the plate-shaped body is freely dropped from such a state, the plate-shaped body before dropping is unduly curved and deformed, and at the time of dropping, it is adversely affected by air resistance as described above. The difficulty of measuring the original surface shape of the plate-like body has been extremely great.

  The present invention has been made in view of the above circumstances, and makes it possible to properly lift and support a plate-like body without applying an undue fluid pressure to the plate-like body. It is a technical subject to accurately measure the original surface shape.

  The present invention devised to solve the above technical problem is a shape measuring device for measuring the surface shape of a plate-like body, which discharges fluid to the plate-like body and places the plate-like body in a flat position. And a measuring means for measuring surface shape data indicating the surface shape of the plate-like body in the floated state, and having a plurality of the fluid floating portions, and It is characterized in that a plurality of fluid floating parts are arranged apart from each other.

  According to such a configuration, the plate-like body is floated in a flat posture by the pressure of the fluid discharged from the plurality of fluid floating portions, and the surface shape data indicating the surface shape is measured in the floating state. Measured by means. For this reason, as in the case where the measurement is performed while the plate-like body is freely dropped, it is not adversely affected by air resistance or the like. In addition, since the plurality of fluid floating portions are separated from each other, a gap region where no fluid is discharged is formed between the discharge regions from which the fluid is discharged from each fluid floating portion. Therefore, under the state where the plate-like body is lifted and supported, excess fluid discharged into the lower space of the plate-like body flows into the gap region. Accordingly, there is no excess fluid in the lower space of the plate-like body, and non-uniform fluid pressure acting on the plate-like body is suppressed. As a result, the inconvenience of bending deformation so that the central portion of the plate-like body is convex upward is suppressed, and the original surface shape of the plate-like body can be accurately measured.

  In such a configuration, it is preferable that an outflow path for allowing the fluid to flow out from the lower space of the plate-like body in the floated state to the outside is formed between the plurality of fluid floating portions. .

  In this way, even if fluid is successively discharged from a plurality of fluid floating parts toward the plate-like body, excess fluid existing in the lower space of the plate-like body does not stay in the lower space but passes through the outflow path. Outflow from the lower space. Thereby, the malfunction that excess fluid remains in the lower space of a plate-shaped object is suppressed reliably.

  In the above configuration, each of the plurality of fluid floating portions is provided with a discharge portion that discharges the fluid on the upper surface of a casing portion that is elongated in one direction. It is preferable that they are arranged in parallel or substantially in parallel.

  In this way, since a plurality of linear gap regions are formed in a substantially parallel state between the plurality of housing parts, the plate is discharged from the discharge part on the upper surface of each housing part. Excess fluid existing in the lower space of the shape body flows along the linear gap region. Thereby, since the flow resistance of the fluid in the gap region is reduced, the situation where the flow of the fluid stagnates in the gap region is suppressed. In addition, since each of the plurality of housing portions has a height, the gap region is widened compared to the case where each fluid floating portion and the space between them are flush with each other. The effect of removing excess fluid from the lower space of the body is increased.

  In the above configuration, the plurality of fluid floating portions may be configured to support the plate-like body in an inclined manner.

  In this way, the excess fluid discharged from the plurality of fluid floating parts toward the plate-like body is allowed to flow out from the lower space of the plate-like body to the outside along the inclined surface of the plate-like body. In addition, the situation in which the plate-like body floats freely in all directions can be avoided.

  In the above configuration, it is preferable that a regulation member that regulates movement of the plate-like body in the main surface direction is provided.

  In this way, even if the plate-like body supported in the levitated state tries to move in the main surface direction, the movement of the plate-like body is regulated by the regulating member, so the surface shape data of the surface of the plate-like body During the measurement, the problem that the plate-like body moves is avoided.

  In the above configuration, the plate-like body has a substantially rectangular shape, and the plurality of fluid floating portions support the plate-like body by tilting downward from one opposing corner to the other corner. It is preferable that it is comprised.

  In this way, when the plate-like body is kept in a fixed position in a floating state, it is only necessary to regulate the movement of one corner portion, so the configuration for that regulation is simplified. Can do. In this case, the inclination angle of the plate-like body with respect to the horizontal plane is preferably 1 degree or less.

  In the above configuration, the separation dimension between the plurality of fluid floating portions is preferably 10 mm or more and 200 mm or less.

  That is, when the above-mentioned separation dimension is less than 10 mm, the fluid discharged from each fluid floating portion only circulates slightly in the gap region between each fluid discharge region, and most of the fluid is plate-shaped. There is a risk of staying in the lower space of the body. On the other hand, when the separation dimension exceeds 200 mm, a large amount of discharged fluid may flow out from a gap region between the fluid discharge regions. Therefore, if the separation dimension is set to 10 mm or more and 200 mm or less, these problems are unlikely to occur. In consideration of the above matters, the separation dimension is more preferably 40 mm or more, and more preferably 120 mm or less.

  In the above configuration, the measurement unit includes a displacement meter that measures non-contact distance information from a previously known position (for example, the position of the displacement meter itself) to the surface of the plate-like body, and the displacement meter A drive scanning unit that drives the plate-like body to scan the surface of the plate-like body, and obtains the distance information at a plurality of locations of the plate-like body by scanning the displacement meter, and the plurality of obtained pieces And a processing unit that generates the surface shape data based on the distance information.

  In this way, if the drive scanning unit is driven and the displacement meter scans the surface of the plate-like body, distance information from the displacement meter to the surface of the plate-like body is acquired at a plurality of locations on the surface of the plate-like body. In addition, the processing unit can promptly generate surface shape data indicating the surface shape of the plate-like body based on the acquired plurality of distance information. Thereby, the surface shape data of the plate-like body in the region where the displacement gauge is moved by the drive scanning unit can be measured quickly and accurately.

  In the above configuration, the calculation for obtaining the correction surface shape data based on the surface shape data measured by the measurement unit and the reference surface shape data indicating the shape of the reference surface passing through the upper surfaces of the plurality of fluid floating portions. It is preferable to further include a part.

  In this way, the corrected surface shape data can be obtained by correcting the surface shape data measured by the measuring unit with the reference surface shape data, so that the surface shape of the plate-like body is changed. It becomes possible to grasp more accurately. The “reference plane” is a single plane composed of each upper surface of the fluid floating surface and a virtual connecting surface that smoothly connects the upper surfaces when no plate-like body is placed on the fluid floating surface. Alternatively, the surface of the plate-like body in a state where the plate-like body is placed on the fluid floating portion where no fluid is discharged may be used.

  In the above configuration, it is preferable to further include an arithmetic unit that obtains the surface shape data for each of the front surface side and the back surface side of the plate-like body and obtains correction surface shape data based on both data.

  In this way, the calculation unit corrects the surface shape data obtained by measuring the surface on one side of the front side or the back side of the plate-like body with the surface shape data obtained by measuring the surface on the other side, thereby correcting the correction surface. Since the shape data is obtained, the surface shape of the plate-like body can be grasped more accurately.

  In the above configuration, the surface shape data is measured for each before and after moving the plate-like body by a half of the separation dimension in the direction in which the plurality of fluid floating parts are separated from each other. It is preferable to further include a calculation unit that obtains correction surface shape data based on both data.

  In this way, the calculation unit corrects the surface shape data measured before moving by ½ of the separation dimension with the surface shape data measured after moving by ½ of the separation dimension. Since the corrected surface shape data is obtained, the surface shape of the plate-like body can be grasped more accurately.

  As described above, according to the present invention, the plate-like body can be properly lifted and supported without improper fluid pressure acting on the plate-like body, so that the original surface shape of the plate-like body can be accurately determined. It becomes possible to measure.

It is a perspective view showing the outline principal part composition of the shape measuring device concerning a 1st embodiment of the present invention. It is a shape measuring apparatus which concerns on 1st Embodiment of this invention, Comprising: The state with which the plate-shaped object was supported by levitation | floating is shown. It is the shape measuring apparatus which concerns on 1st Embodiment of this invention, Comprising: The state which is measuring the distance information from a displacement meter to a plate-shaped object is shown. FIG. 2 is a vertical sectional view taken along line AA in FIG. 1. It is the BB line longitudinal cross-sectional view of FIG. It is a block diagram until the correction | amendment surface shape data of the plate-shaped body in the 1st example which concerns on 1st Embodiment of this invention is calculated | required. It is a block diagram until the correction | amendment surface shape data of the plate-shaped body in the 2nd example which concerns on 1st Embodiment of this invention is calculated | required. It is a block diagram until the correction | amendment surface shape data of the plate-shaped body in the 3rd example which concerns on 1st Embodiment of this invention is calculated | required. FIG. 9 (a) is a shape measuring apparatus according to a third example according to the first embodiment of the present invention, and is a perspective view showing a schematic configuration of a main part that measures distance information to a plate-like body at a first position. FIG. FIG. 9B is a perspective view showing a schematic configuration of the main part for measuring the distance information to the plate-like body after moving from the first position to the second position. It is a perspective view which shows the outline principal part structure of the shape measuring apparatus which concerns on 2nd Embodiment of this invention. It is a perspective view which shows the outline principal part structure of the shape measuring apparatus which concerns on 3rd Embodiment of this invention. It is CC longitudinal cross-sectional view of FIG. It is a perspective view which shows the schematic principal part structure of the shape measuring apparatus which concerns on 4th Embodiment of this invention.

  Hereinafter, a shape measuring apparatus according to an embodiment of the present invention will be described with reference to the drawings.

  1 and 2 illustrate a schematic configuration of the shape measuring apparatus 1 according to the first embodiment of the present invention. As shown in each of these drawings, the shape measuring apparatus 1 floats as a main component, a plurality of fluid floating parts (housing parts) 2 that support the plate-like body G in a state of being floated in a flat position. And a measurement unit 3 that measures surface shape data indicating the surface shape of the plate-like body G maintained in a non-contact state. In this case, the plate-like body G is constituted by a substantially rectangular glass substrate in the present embodiment, and the size of the glass substrate G is 600 to 3500 mm (in this embodiment, 2500 mm) on one side, and the other adjacent to this. The dimension of the side is 500 to 3200 mm (2200 mm in this embodiment), and the thickness is 0.2 to 1.1 mm (0.5 mm in this embodiment).

  Each of the plurality of fluid floating portions 2 has a discharge portion 2ax (portion with cross-hatching in the figure) on the upper surface 2a of the elongated rectangular parallelepiped housing portion 2 elongated in one direction. It is configured. The plurality of casings 2 are arranged in parallel or substantially in parallel, and are spaced apart from each other via a gap 4. In other words, a gap portion 4 having a distance D and a height h is provided between the plurality of housing portions 2, and accordingly, the discharge portions 2 ax on the upper surface 2 a are mutually connected. Are arranged with an interval of D.

  In this case, the distance D is 10 mm or more and 200 mm or less (100 mm in this embodiment), and the height h is 10 mm or more and 200 mm or less (100 mm in this embodiment). Furthermore, the number of the housing parts 2 is two or more (six in this embodiment). In addition, each casing unit 2 has a longitudinal dimension of 500 mm or more and 4000 mm or less (2800 mm in this embodiment), and a dimension perpendicular to the longitudinal direction (width direction) is 50 mm or more. And it is 200 mm or less (in this embodiment, 100 mm). Although not shown in detail, the upper surface 2a of each housing portion 2 is formed with a large number of discharge holes for discharging fluid, thereby forming the discharge portion 2ax.

  The measuring unit 3 includes a laser displacement meter 3a as a displacement meter, and the laser displacement meter 3a is a distance from a previously known position (for example, the position of the laser displacement meter 3a itself) to the surface of the glass substrate G. It is configured to measure information without contact. Further, the measurement unit 3 includes a drive scanning unit (not shown) including a gantry device that scans the surface of the glass substrate G by driving the laser displacement meter 3a above the glass substrate G, and a plurality of glass substrates G by scanning. And a processing unit 3b that measures distance information at the location and generates surface shape data indicating the surface shape of the glass substrate G based on the distance information.

  Here, the laser displacement meter 3a is arranged at a constant height in a direction orthogonal to the surface of the glass substrate G, and irradiates the laser to the glass substrate G to reduce the distance to the surface of the glass substrate G. It is measured by contact. The laser displacement meter 3a includes a diffusion method, a regular reflection method, and the like. However, considering that the glass substrate G is a transparent body, it is preferable to use a regular reflection method laser displacement meter 3a. Further, as the laser displacement meter 3a, it is preferable to use a laser displacement meter 3a capable of performing measurement by a laser trigonometry or a confocal method in consideration of distance resolution and the like. Instead of the laser displacement meter 3a, a non-contact displacement meter using air micro, light, ultrasonic wave or the like as a medium can be used, and photographing means such as a camera for photographing the surface shape of the glass substrate G Can also be used.

  FIG. 3 illustrates a state in which the laser displacement meter 3a is scanning the upper surface of the glass substrate G that is levitated and supported. As shown in the figure, the laser displacement meter 3a can freely scan the upper surface of the glass substrate G in the vertical and horizontal directions (X direction and Y direction) by driving a gantry device or the like. The laser displacement meter 3a can be scanned so as to meander on the upper surface of the glass substrate G. Further, the laser displacement meter 3a can be moved in the vertical direction (Z direction) by a gantry device or the like, whereby the height of the laser displacement meter 3a can be adjusted. As the drive scanning unit, a robot arm or the like may be used instead of the gantry device or the like.

  4 is a longitudinal sectional view taken along line AA in FIG. As shown in the figure, the plurality of housing parts 2 are inclined by an angle α so that the glass substrate G is levitated and supported from one opposing corner to the other corner. It is arranged. More specifically, the inclined plane h2 including all the bottom surfaces 2b of the plurality of housing parts 2 shown in FIG. 4 is supported so that the glass substrate G shown in FIG. The angle α is inclined with respect to the horizontal plane H1. Accordingly, the inclined plane H3 including all the upper surfaces 2a (discharge portions 2ax) of the plurality of casings 2 is similarly inclined by the angle α with respect to the horizontal plane H1. This angle α is set to 1 degree or less, preferably 0.5 degrees or less, more preferably 0.1 degrees or less, and 0.05 degrees in this embodiment.

  Further, as shown in FIGS. 1 to 3, a plurality of regulating members 6 made of resin, rubber, metal, or the like that regulate the movement of the glass substrate G are provided in the direction of the corner portion G1 where the glass substrate G is inclined downward. It is erected. These regulating members 6 have a columnar shape or a cylindrical shape, and their side surfaces are in contact with two sides Ga and Gb forming a corner portion G1 in a direction in which the glass substrate G is inclined downward. In the present embodiment, these regulating members 6 have a plurality of (two in the illustrated example) abut on one side Ga along the longitudinal direction of the housing portion 2 among the four sides of the glass substrate G. About the other side Gb along the direction orthogonal to it, it arrange | positions so that one may contact | abut. Therefore, although the glass substrate G is inclined, the movement in the principal surface direction is restricted by the contact with the restricting member 6 and is stably held at the fixed position.

  FIG. 5 is a longitudinal front view cut along the line BB in FIG. 2, and exaggerates the state in which the glass substrate G is lifted and supported. As shown in the figure, the glass substrate G is levitated and supported by the fluid discharged from the discharge portions 2ax on the upper surface 2a of the plurality of spaced apart housing portions 2, but the lower portion of the levitated glass substrate G In the space, a plurality of fluid discharge regions 7 and a gap region 8 (a region composed of the gap portion 4 and the upper portion thereof) where fluid is not discharged are formed. The gap region 8 is a part into which excess fluid existing in the lower space of the glass substrate G flows, and also serves as an outflow path through which the excess fluid flows out from the lower space of the glass substrate G. Therefore, the glass substrate G is levitated and supported in a state where the original surface shape is likely to appear.

  In particular, in the gap region 8, the glass substrate G is levitated and supported in a state where the fluid discharge force does not act directly. Therefore, in the gap region 8 and its peripheral portion, the width direction center of the fluid discharge region 7 Furthermore, it is considered that the original surface shape of the glass substrate G is likely to appear. Therefore, ideally, it is considered preferable to measure the surface shape data of the glass substrate G mainly in the gap region 8 and its peripheral portion. However, in any case, when the fluid discharge mode is as described above, the original surface shape (surface shape having warpage or undulation) or a surface shape close thereto appears across the entire area of the glass substrate G. Yes. Then, when the laser displacement meter 3a scans the upper surface of the glass substrate G in such a state, appropriate surface shape data of the glass substrate G is measured by the measuring unit 3.

  FIG. 6 is a block diagram according to the first example of the present embodiment, in which the surface shape data of the glass substrate G in the floating support state measured by the measurement unit 3 and the reference surface shape measured by the measurement unit 3 The schematic structure until correction surface shape data is calculated | required based on data is illustrated. Here, in the present embodiment, the reference surface shape data is a state in which the glass substrate G is placed on the upper surfaces 2a of the plurality of casing portions 2 from which no fluid is discharged (a state in which the weight of the glass substrate directly acts). The surface shape data measured by the measuring unit 3. The reference surface shape data is composed of the surface shape data obtained by measuring the upper surfaces 2a of the plurality of casings 2 where no fluid is discharged by the measuring unit 3, and the virtual connecting surfaces that smoothly connect the upper surfaces 2a. However, in this case, the influence of the weight of the glass substrate G should be considered for the virtual connection surface.

  As shown in the figure, a signal indicating distance information is sent from the laser displacement meter 3a of the measurement unit 3 to the processing unit 3b. The processing unit 3b includes a reference surface shape data processing unit 3b1 and a surface shape data processing unit. 3b2. Therefore, after the signal from the laser displacement meter 3a is sent to the reference surface shape data processing unit 3b1 and the surface shape data processing unit 3b2, the signals from both the processing units 3b1, 3b2 are sent to the calculation unit 5. Sent out. According to such a configuration, the reference surface shape data processing unit 3b1 generates the reference surface shape data as described above, and the surface shape data processing unit 3b2 generates the surface of the glass substrate G that is in the floating support state. Shape data is generated. Then, the correction surface shape data corresponding to the difference between the surface shape data of the glass substrate G in the floating support state and the reference surface shape data is obtained by the calculation unit 5.

  FIG. 7 is a block diagram according to a second example of the present embodiment, and a correction surface based on both-side shape data on the front side and the back side of the glass substrate G in the floating support state measured by the measurement unit 3. The schematic structure until shape data is calculated | required is illustrated. As shown in the figure, the processing unit 3b of the measurement unit 3 includes a front surface shape data processing unit 3b3 and a back surface shape data processing unit 3b4. Therefore, the signal from the laser displacement meter 3a is sent to the front surface shape data processing unit 3b3 and the back surface shape data processing unit 3b4, and then the signals from both the processing units 3b3 and 3b4 are sent to the calculation unit 5. The According to such a configuration, the surface shape data processing unit 3b3 generates surface shape data of the surface of the glass substrate G in the floating support state, and the back surface shape data processing unit 3b4 generates the glass in the floating support state. Surface shape data of the back surface of the substrate G is generated. Then, the calculation unit 5 obtains correction surface shape data corresponding to the difference between the surface shape data of the front surface and the surface shape data of the back surface.

  FIG. 8 is a block diagram according to the third example of the present embodiment, which is corrected based on both-side shape data before and after the movement in the glass substrate G in the floating support state measured by the measurement unit 3. The schematic structure until surface shape data is calculated | required is illustrated. As shown in the figure, the processing unit 3b of the measurement unit 3 includes a first surface shape data processing unit 3b5 and a second surface shape data processing unit 3b6. Therefore, after the signal from the laser displacement meter 3a is sent to the first surface shape data processing unit 3b5 and the second surface shape data processing unit 3b6, the signals from both the processing units 3b5 and 3b6 are calculated by the calculation unit. 5 is sent out. Here, the first surface shape data processing unit 3b5 generates surface shape data when the glass substrate G in the floating support state is present at the first position, and the second surface shape data processing unit. 3b6 is for generating surface shape data when the glass substrate G in the floating support state is present at the second position moved by ½ of the distance D from the first position. According to such a configuration, the surface shape data at the first position generated by the first surface shape data processing unit 3b5 and the surface at the second position generated by the second surface shape data processing unit 3b6. The shape data is synthesized by the calculation unit 5 to obtain correction surface shape data. Specifically, as described above, the original surface shape is likely to appear on the glass substrate G that is levitated and supported in the gap region 8 and its peripheral portion, rather than the central portion in the width direction of the fluid discharge region 7. It is thought that there is. Therefore, if two types of surface shape data are generated before and after moving the glass substrate G in the floating support state by a half of the interval D, the surface shape data in the gap region 8 and its peripheral portion is widened. Can be generated. Then, the calculation unit 5 can obtain highly accurate corrected surface shape data by combining the two types of surface shape data so that priority is given to a data portion where the original surface shape is more likely to appear.

  FIG. 9A illustrates a mode when the glass substrate G is in the first position, and FIG. 9B illustrates a mode when the glass substrate G is in the second position. doing. As shown in each of these drawings, a swivel arm body is provided on the upper part of two regulating members 6 erected so as to be able to come into contact with one side of the side of the glass substrate G along the longitudinal direction of the housing portion 2. Each of the two regulating members 6 is rotatably held while 6a is fixed. Then, as shown in FIG. 9A, if the two regulating members 6 are rotated 90 degrees from the state in which the tip end surface of the swing arm body 6a is in contact with one side of the glass substrate G, the swing arm body 6a tries to be separated from one side of the glass substrate G. However, since the glass substrate G is inclined downward in the direction of the corner portion G1 where the regulating member 6 exists, as shown in FIG. Moving leftward, one side of the glass substrate G comes into contact with the side surface of the swing arm body 6a (in the direction of the arrow in the figure). Thereby, the glass substrate G moves to the 2nd position from the above-mentioned 1st position. Therefore, if such a mechanism is employed, the glass substrate G can be moved accurately and easily. In addition, let the aspect shown in FIG.9 (b) be an aspect when the glass substrate G exists in the above-mentioned 1st position, and rotate two control members 6 90 degree | times to the opposite direction from the above from this state. It is good also as a mode corresponding when the glass substrate G exists in the above-mentioned 2nd position shown to Fig.9 (a).

  As described above, according to the shape measuring apparatus 1 according to the first embodiment, the casings 2 as the plurality of fluid floating portions are arranged apart from each other, thereby discharging the casings 2. Since a gap region 8 where no fluid is discharged is formed between the discharge regions 7 where the fluid is discharged from the portion 2ax, the portion 2ax is discharged into the lower space of the glass substrate G in a floating support state. Excess fluid flows into the gap region 8 and then flows out through the outflow passage 4. Accordingly, there is no excess fluid in the lower space of the glass substrate G, and non-uniform fluid pressure acting on the glass substrate G is suppressed. As a result, the problem that the glass substrate G is curved and deformed so that the central portion of the glass substrate G is convex upward is suppressed, and the original surface shape of the glass substrate G can be accurately measured.

  In addition, as a fluid source of the fluid discharged to the glass substrate G, the thing which passed the HEPA filter (High Efficiency Particulate Air Filter) or the CDA (Clean Dry Air) to the blower is preferable, and the inert gas is used as the discharged fluid. preferable. Moreover, the discharge part 2ax can also be formed with a porous metal sintered body (sintered metal), a resin, or the like.

  And by using air or nitrogen as an inert gas discharged to the glass substrate G, the total cost required for the inspection of the glass substrate G can be suppressed. Here, when the fluid discharged from the discharge part 2ax of the housing part 2 is air, it is preferable to use compressed air compressed by a compressor, and the dew point is reduced to −50 ° C. with a dryer or the like. The lowered one is more preferable. And even if the temperature of the air discharged from the plurality of fluid floating parts 2 is lowered by adiabatic expansion by using the compressed air whose dew point is lowered to at least −20 ° C., glass is discharged by the discharged air. It is possible to prevent the substrate G from being cooled and causing condensation. As a result, it is possible to prevent moisture in the air from adhering to the glass substrate G and affecting the measurement of the surface shape of the glass substrate G. In addition to compressed air, nitrogen gas obtained by volatilizing liquid nitrogen can also be used. In this case, it is preferable to use nitrogen gas that has been sufficiently heated by a heat exchanger or the like. As a result, when nitrogen gas is discharged onto the glass substrate G, the glass substrate G is cooled, thereby preventing water in the air from aggregating on the surface of the glass substrate G.

  FIG. 10 illustrates the shape measuring apparatus 1 according to the second embodiment of the present invention. The shape measuring apparatus 1 according to the second embodiment is different from that according to the first embodiment described above in that a plurality of housing portions 2 are arranged apart from each other not only in the width direction but also in the longitudinal direction. Is where you are. Therefore, the gaps 4 and the outflow passages are arranged vertically and horizontally with a distance D. According to such a configuration, since the conditions for levitating the glass substrate G are uniformed in the vertical and horizontal directions, it can be inferred that the surface shape data measured by the measuring unit 3 is free from deviations in directionality. About the point other than this, the same effect as the above-mentioned 1st Embodiment is acquired. Since the other constituent elements are the same as those in the first embodiment described above, the constituent elements common to both are denoted by the same reference numerals and the description thereof is omitted.

  FIG. 11 illustrates the shape measuring apparatus 1 according to the third embodiment of the present invention. The shape measuring apparatus 1 according to the third embodiment is different from that according to the first embodiment described above in that the fluid floating portion 2 and the gap portion 4 exist on the same plane or substantially the same plane. Is where you are. In this case, as shown in FIG. 12, since there is no recess between the fluid floating portions 2, the fluid pressure in the lower space of the glass substrate G in the floating support state is considered to be stable. It is necessary to increase the discharge amount of the fluid discharged from the floating part 2. In this case, a gap region 8 and thus an outflow path 4 are formed between the discharge regions 7 of the plurality of fluid floating portions 2. About the point other than this, the same effect as the above-mentioned 1st Embodiment is acquired. Since the other constituent elements are the same as those in the first embodiment described above, the constituent elements common to both are denoted by the same reference numerals and description thereof is omitted.

  FIG. 13 illustrates the shape measuring apparatus 1 according to the fourth embodiment of the present invention. The shape measuring device 1 according to the fourth embodiment is different from that according to the third embodiment described above in that a plurality of fluid floating portions 2 are arranged apart from each other not only in the width direction but also in the longitudinal direction. It is in place. Therefore, the gaps 4 and the outflow passages are arranged vertically and horizontally with a distance D. According to such a configuration, since the conditions for levitating the glass substrate G are uniformed in the vertical and horizontal directions, it can be inferred that the surface shape data measured by the measuring unit 3 is free from deviations in directionality. About the point other than this, the same effect as the above-mentioned 3rd Embodiment is acquired. Since the other components are the same as those in the third embodiment described above, the components common to both are given the same reference numerals and the description thereof is omitted.

DESCRIPTION OF SYMBOLS 1 Shape measuring apparatus 2 Fluid floating part 2a Upper surface 2ax of fluid floating part Discharge part 3 Measuring part 3a Laser displacement meter 3b Processing part 4 Outflow path, gap | interval part 5 Calculation part 6 Control member G Glass substrate (plate-shaped body)
G1 Corner

Claims (11)

A shape measuring device for measuring the surface shape of a plate-shaped body,
A fluid floating portion that discharges fluid to the plate-like body and supports the plate-like body in a state of being floated in a flat position, and surface shape data indicating a surface shape of the plate-like body in the floated state. A measuring unit for measuring,
A plurality of the fluid floating portions, and the plurality of fluid floating portions are arranged apart from each other ,
The plurality of fluid floating portions support the plate-like body having a substantially rectangular shape by tilting downward from one opposing corner portion to the other corner portion, and forming the other corner portion. In addition, the measurement unit measures surface shape data indicating the surface shape of the plate-like body when the restriction member for restricting movement of the plate-like body in the principal surface direction is in contact with the plate-like body. A shape measuring device.   2. The outflow passage through which the fluid flows out from the lower space of the plate-like body in the floated state to the outside is formed between the plurality of fluid floating portions. Shape measuring device.   Each of the plurality of fluid floating portions is provided with a discharge portion that discharges the fluid on an upper surface of a casing portion that is elongated in one direction, and the plurality of casing portions are parallel or substantially parallel to each other. The shape measuring apparatus according to claim 1, wherein the shape measuring apparatus is arranged in parallel. The shape measuring apparatus according to any one of claims 1 to 3 , wherein a spacing dimension between the plurality of fluid floating parts is 10 mm or more and 200 mm or less. The measurement unit includes a displacement meter that measures distance information from a previously known position to the surface of the plate-like body in a non-contact manner, and the displacement meter is driven above the plate-like body to move the plate-like body. A driving scanning unit that scans the surface of the plate, and the distance information at a plurality of locations of the plate-like body is acquired by scanning the displacement meter, and the surface shape data is generated based on the acquired plurality of distance information. shape measuring device according to any one of claims 1-4, characterized in that it comprises a processing unit. A calculation unit for obtaining correction surface shape data based on the surface shape data measured by the measurement unit and the reference surface shape data indicating the shape of the reference surface passing through the upper surfaces of the plurality of fluid floating portions; shape measuring apparatus according to any one of claims 1 to 5, wherein. It obtains the surface shape data for each of the first surface and the second surface of the plate-like body, on the basis of these two data, claim, characterized by further comprising a calculation unit for obtaining the correction surface shape data 1-5 The shape measuring device according to any one of the above. The surface shape data is measured before and after the plate-like body is moved by a half of the separation dimension in the direction in which the plurality of fluid floating parts are separated from each other, and based on both data the shape measuring apparatus according to any one of claims 1 to 5, further comprising a calculation unit for obtaining the correction surface shape data.   A shape measuring device for measuring the surface shape of a plate-shaped body,
  A fluid floating portion that discharges fluid to the plate-like body and supports the plate-like body in a state of being floated in a flat position, and surface shape data indicating a surface shape of the plate-like body in the floated state. A measuring unit for measuring,
  A plurality of the fluid floating portions, and the plurality of fluid floating portions are arranged apart from each other,
The surface shape data is measured before and after the plate-like body is moved by a half of the separation dimension in the direction in which the plurality of fluid floating parts are separated from each other, and based on both data A shape measuring device further comprising a calculation unit for obtaining correction surface shape data. The outflow path for allowing the fluid to flow out from the lower space of the plate-like body in the floated state to the outside is formed between the plurality of fluid floating portions. Shape measuring device. Each of the plurality of fluid floating portions is provided with a discharge portion that discharges the fluid on an upper surface of a casing portion that is elongated in one direction, and the plurality of casing portions are parallel or substantially parallel to each other. The shape measuring device according to claim 9 or 10, wherein the shape measuring device is arranged in parallel.

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