KR101442895B1 - Method for measuring external shape of rectangular plate-like object, and method for calibrating relative position of image-capturing means - Google Patents

Abstract

The outer shape of the rectangular rectangular plate-shaped object to be conveyed is measured using a shape measuring device including four imaging means previously arranged corresponding to the four corners of the rectangular plate shaped object and storing means for storing the relative coordinates of each of the four imaging means A step of judging whether or not the rectangular plate-shaped article has reached the measuring section; and a step of judging whether or not the image including corner portions of each of the four corners of the rectangular plate- A step of calculating a corner post coordinate which is a coordinate value from an image origin of each of the four corners of the rectangular plate-shaped object based on the picked-up image; Based on the coordinates, the length dimension of each of the four sides of the rectangular plate-shaped object and the rectangular angle of each of the four corners are calculated The steps to be performed are provided.

Description

TECHNICAL FIELD [0001] The present invention relates to a method of measuring an external shape of a rectangular plate-shaped object and a relative position correcting method of the imaging means. BACKGROUND OF THE INVENTION 1. Field of the Invention [0002]

The present invention relates to a measuring method for measuring an outer shape (dimension and rectangular angle of four corners) of a rectangular plate-shaped article such as a glass plate, and more particularly to a measuring method for measuring the outer shape of a rectangular plate- And the like) can be measured non-stop.

Conventionally, in the field of glass plates such as a glass plate for liquid crystal display, a glass plate for plasma display, a glass plate for field emission display, and a glass plate for flat display panel such as organic EL and the like, the outer shape (dimensions and four- It is necessary to take an image of the glass plate and measure the external shape of the glass plate (dimensions and rectangularity of the four corners) of the glass plate based on the image picked up by the glass plate, (For example, refer to Patent Document 1 below).

FIG. 10 is a front view of the shape measuring apparatus disclosed in Patent Document 1. FIG. Fig. 11 is a side view of the shape measuring apparatus disclosed in Patent Document 1. Fig.

10 and 11, the shape measuring apparatus 100 described in Patent Document 1 includes an X-axis guide 102 extending in the X-axis direction and a Y-axis guide 104 extending in the Y-axis direction, (Not shown) for moving the imaging means 106 and the imaging means 106 along the X-axis and Y-axis guides 102 and 104 in the X and Y directions, and the like.

11, the edge of the glass plate 110 carried in the inclined posture and supported on the inspection table 108 is moved in the XY direction by moving the imaging means 106 in the XY direction And the outer shape of the glass plate 110 (such as the dimension and the squareness of the four corners) is automatically measured based on the captured image and the like.

Japanese Patent Application Laid-Open No. 2007-205724

However, since the shape measuring apparatus 100 is configured to pick up the edge of the glass plate 110 by using the imaging unit 106 moving in the XY directions, the glass plate 110 is placed on the inspection table 108, It is impossible to measure the shape non-stop with respect to each of the plurality of glass plates 110 transported on the line, so that it takes time to measure and the feedback to the manufacturing conditions is slowed down when a defect occurs. As a result, there is a problem that the yield can not be improved.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances and has as its object to provide a measurement method capable of non-stop measurement of the external shape (dimensions, rectangular angle of four corners, etc.) of a rectangular plate- .

In order to achieve the above object, the present invention uses a shape measuring device having four imaging means arranged in advance corresponding to four corners of a rectangular plate-shaped object and storage means for storing relative coordinates of each of the four imaging means And measuring a shape of the rectangular plate-like object conveyed to pass through the shape measuring section, the method comprising the steps of: determining whether the rectangular plate-shaped article has reached the measurement section; The method comprising the steps of: capturing an image including corners of each of four corners of a rectangular plate-shaped article which has reached the measurement section by the four imaging means; and, based on the captured image, Calculating corner post coordinates which are coordinate values from the image origin of each of the four corners of the water; Calculating a length dimension of each of the four sides of the rectangular plate-shaped object based on corner post coordinates of the rectangular plate-like object and relative coordinates stored in the storage means; calculating the relative corner coordinates, the relative coordinates stored in the storage means, And a step of calculating a squareness of each of the four corners of the rectangular plate-like object based on the calculated length dimension.

According to the above arrangement, the four corners of the four corners of the rectangular plate-shaped object can be simultaneously (or substantially simultaneously) formed by the four imaging means arranged in correspondence with the four corners of the rectangular plate- (The length dimension of each of the four sides of the rectangular plate-like object and the rectangular angle of each of the four corners of the rectangular plate-like object) of the rectangular plate-shaped object is calculated based on the captured image or the like. This makes it possible to non-stop the shape measurement on each of the plurality of rectangular plate-shaped articles conveyed on the line, thereby making it possible to improve the yield.

The method further includes a step of comparing the computed length dimension and the squareness with a predetermined standard value, and a step of determining a failure of the outer shape of the rectangular plate-shaped object based on the comparison result .

According to the above-described configuration, it is possible to determine the defective shape of the rectangular plate-shaped object.

The method for measuring an external shape of the present invention is a method for measuring an external shape of a calibration standard rectangular plate having a predetermined length of each of four sides of a standard rectangular plate for calibration and a predetermined rectangular angle of each of the four corners of the standard rectangular plate for calibration, A step of correcting a previously measured rectangularity of each of the four corners of the standard rectangular plate-shaped object; a step of picking up an image including corners of each of the four corners of the standard rectangular plate for calibration by the four imaging means; Calculating corner post coordinates of each of the four corners of the standard rectangular plate for calibration on the basis of the image obtained by the calculation of the corner post coordinates of the calibration standard rectangular plate; Based on the previously measured length dimensions of each of the four sides of the plate-like object, calculates the relative coordinates of each of the four image pickup means W, it may further comprise the step of storing in the storage means.

According to the above arrangement, by using the standard rectangular plate for calibration (preliminarily known) measuring the length dimension of each of the four sides and the rectangular angle of each of the four corners, the rectangular shape of the rectangular plate- It is possible to calculate the relative coordinates of each of the four imaging units as the basis of the calculation of the length dimension of each side and the rectangular angle of each of the four corners of the rectangular plate-shaped object.

In addition, since the step of correcting the previously measured squareness of each of the four corners of the standard rectangular plate for calibration is provided, the length dimension of each of the four sides of the standard rectangular plate for calibration and the squareness of each of the four corners Even if a measurement error is included, the measurement error is canceled. This makes it possible to calculate the relative coordinates of each of the four imaging units with higher accuracy.

The present invention also provides a method of calibrating the relative coordinates of the four imaging units in a shape measuring apparatus including four imaging units arranged in correspondence with the four corners of a rectangular plate in advance, Corrects the previously measured rectangularness of each of the four corners of the standard rectangular plate for calibration on the basis of the pre-measured length dimension of each of the four sides of the water and the pre-measured rectangular angle of each of the four corners of the standard rectangular plate for calibration A step of picking up an image including corners of each of the four corners of the standard rectangular plate for calibration by the four imaging means; and a step of, based on the picked-up image, Calculating corner post coordinates of the standard rectangular plate for calibration, calculating the corner post coordinates of the standard rectangular plate for calibration, And calculating the relative coordinates of each of the four imaging means based on the angle of inclination of the imaging means and the previously measured length dimension of each of the four sides of the orthodontic standard rectangular plate, Provides a calibration method.

According to the above configuration, by using the (standard) orthodontic standard rectangular plate material having the length dimensions of each of the four sides and the squareness of each of the four corners in advance, the outer shape of the rectangular plate- And the relative coordinates of each of the four imaging units as the basis of the arithmetic operation of the dimensions and the rectangular angles of the four corners of the rectangular plate-like object).

In addition, since the step of correcting the previously measured squareness of each of the four corners of the standard rectangular plate for calibration is provided, the length dimension of each of the four sides of the standard rectangular plate for calibration and the rectangular angle of each of the four corners Even if a measurement error is included, the measurement error is canceled. This makes it possible to calculate the relative coordinates of each of the four imaging units with higher accuracy.

INDUSTRIAL APPLICABILITY As described above, according to the present invention, it becomes possible to provide a measurement method capable of non-stop measurement of the outer shape (dimensions, rectangular angle of four corners, etc.) of a rectangular plate-shaped article such as a glass plate conveyed on a line.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a system configuration diagram of a shape measuring apparatus applied to a method of measuring an outer shape of a rectangular plate-shaped article of the present embodiment. Fig.
2 is a diagram for explaining a general manufacturing process of a glass plate.
3 is a plan view in the vicinity of the shape measuring section 32 on the measuring line 30. Fig.
4 is a diagram for explaining the positional relationship between the four sides and corner portions of the standard glass plate 36 for correction and the imaging means 18C0 to 18C3.
5 is an example of images P1 to P4 taken by each of the imaging units 18C0 to 18C3.
Fig. 6 is a flowchart for explaining processing for calculating the relative coordinates of each of the four imaging units 18C0 to 18C3.
7 is a graph showing the relationship between the lengths E1, E2, ER and EL of each of the four sides of the standard glass plate 36 for correction and the angles ∠1 to ∠4 of the four corners of the standard glass plate 36 FIG.
Fig. 8 is a diagram for explaining the relationship between the relative coordinates S0 to S3 and the approximate correction angles R1 * and R2 * of the four imaging units 18C0 to 18C3, respectively.
9 is a flowchart for explaining a method of measuring the contour shape of the work glass plate 34. Fig.
FIG. 10 is a front view of the shape measuring apparatus disclosed in Patent Document 1. FIG.
Fig. 11 is a side view of the shape measuring apparatus disclosed in Patent Document 1. Fig.

Best Mode for Carrying Out the Invention Hereinafter, preferred embodiments of a method of measuring the external shape of a rectangular plate-shaped article according to the present invention will be described in detail with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a system configuration diagram of a shape measuring apparatus applied to a method of measuring an outer shape of a rectangular plate-shaped article of the present embodiment. Fig. 2 is a diagram for explaining a general manufacturing process of a glass plate. 3 is a plan view in the vicinity of the shape measuring section 32 on the measuring line 30. Fig.

[Outline of shape measuring apparatus]

As shown in Fig. 2, the glass plate generally has a cutting process for cutting a plate glass produced to a predetermined thickness into a predetermined size, a chamfering process for chamfering the glass plate after the cutting, · It is manufactured through a cleaning and drying process for drying, and a measuring process (measuring line) for measuring the external shape of the glass plate after cleaning and drying.

The shape measuring apparatus 10 of the present embodiment is an apparatus for measuring the external shape of a glass plate and is provided in the shape measuring section 32 on the measuring line 30 as shown in Fig. A rectangular glass plate having a length L (several m) and a width W (several m) shown in Fig. 3 (hereinafter referred to as a work glass plate) shown in Fig. 3) (Not shown) on the measuring line 30, and passes through the shape measuring section 32. The shape measuring apparatus 10 can automatically and non-stop the outer shape of the work glass plate 34 passing through the shape measuring section 32 (the length dimension of each of the four sides of the work glass plate 34 and the four- .

[Configuration of shape measuring apparatus]

1, the shape measuring apparatus 10 is connected to an image processing apparatus 12, an image processing apparatus 12 via an LED power supply 14, and four lights (not shown) Means 16 and four image pickup means 18C0 to 18C3 connected to the image processing apparatus 12 via a predetermined interface (not shown), and an image processing apparatus 12 via a predetermined interface (not shown) And a sensor 20, etc.

The image processing apparatus 12 includes an arithmetic / control unit 12a such as an MPU or a CPU, a storage unit 12b such as a RAM or a ROM, and the like. The image processing apparatus 12 includes control means 12a for controlling each of the illumination means 16 and each of the image pickup means 18C0 to 18C3 by causing the arithmetic and control means 12a to execute a predetermined program read into the storage means 12b, And an operation means for calculating an outer shape of the work glass plate 34. [

The illumination means 16 is for illuminating the four corners of the work glass plate 34 and is, for example, an illumination device including a plurality of LED light sources (not shown) arranged in a ring shape. As shown in Fig. 1, the illuminating means 16 are disposed at four places corresponding to the four corners of the work glass plate 34, respectively. The illuminating means 16 is turned on in accordance with the control from the image processing apparatus 12 to illuminate the four corners of the work glass plate 34.

The image pickup means 18C0 to 18C3 are for picking up the four corners of the work glass plate 34 and are provided with image pick-up devices including CCD type or CMOS type image pickup devices (for example, resolution: several tens of μm / pic) Device. The imaging units 18C0 to 18C3 are arranged so that the corner portions C1 to C4 of each of the four corners of the work glass plate 34 (see Figs. 1, 3, 4, Four corners of the work glass plate 34 so as to enter the four corners of the work glass plate 34, The imaging units 18C0 to 18C3 pick up images P1 to P4 including the corners C1 to C4 at four corners of the work glass plate 34 under the control of the image processing apparatus 12. [ 5 is an example of images P1 to P4 captured by the respective imaging units 18C0 to 18C3. The captured images P1 to P4 are introduced into the image processing apparatus 12. [

The sensor 20 is for detecting whether or not the work glass plate 34 to be measured reaches the measurement section 32 (predetermined imaging position in), and is, for example, a photo interrupter. The sensor 20 notifies the image processing apparatus 12 of the detection signal of the end edge 34a (edge) of the work glass plate 34 in the carrying direction. The image processing apparatus 12 that has received the notification controls each illumination means 16 so as to illuminate four corners of the work glass plate 34 reaching the measurement section 32. At the same time, each of the image pickup means 18C0 to 18C3 is controlled so as to pick up an image including the corners C1 to C4 at four corners of the work glass plate 34. [

[Relative coordinate calculation processing using a standard glass plate for calibration (calibration method)]

Next, the process of calculating the relative coordinates of each of the four imaging units 18C0 to 18C3 using the standard glass plate for correction will be described with reference to Fig. Fig. 6 is a flowchart for explaining processing for calculating the relative coordinates of each of the four imaging units 18C0 to 18C3. The following processing is realized by the image processing apparatus 12 (calculation / control means) executing a predetermined program read into the storage means 12b or the like.

As shown in Figs. 4 and 7, the length dimensions E1, E2, EF, and ER of each of the four sides of the standard glass plate 36 for correction and the squareness ∠1 of each of the four corners of the standard glass plate for correction 36 4 are measured using a calibration gauge such as a linear gauge in advance, and are stored in the storage means 12b or the like as shown in Table 1 below.

Right Angle Draft, orthogonal standard glass plate to be orthogonal (36) 4 means the size of deviation of the angle of each corner from the right angle. In the present embodiment, when it is assumed that the points on the standard glass plate 36 for calibration, which are separated from the corners C1 to C4 of the four corners of the standard glass plate for correction 36 by 1000 mm, and the inner angles of the four corners, (Mm) of the point on the standard glass plate 36 for calibration, which is spaced 1000 mm from the corners C1 to C4 of the four corners of the standard glass plate for correction 36, was used as the perpendicular angle. The difference between the internal angles of the four corners of the standard glass plate for correction 36 and the internal angle of each of the four corners of the standard glass plate 36 when the internal angles of the four corners are assumed to be right angles, May be employed as the right angle.

However, the measurement error itself (offset error of the calibration gauge) is already included in the measured values themselves (particularly, the rectangular angles ∠1 to ∠4). The measurement angles are canceled and the rectangular angles ∠1 to ∠4 are corrected so that the sum of the inner angles of the four corners of the standard glass plate for correction is four right angles (step S10).

More specifically, as shown in the following Table 2, Numbers 1 and 3, the perpendicular angles ∠1 to ∠4 are corrected.

In Table 2, DWSn ← ∠n / 1000 indicates that ∠1 to ∠4 perpendicular to the variables DWS1 to DWS4 are divided into ∠1 / 1000 to ∠4, which is obtained by dividing the squareness ∠1 to ∠4 by the squareness measuring point and the distance between the corners C1 to C4, ∠4 / 1000 are respectively substituted. Rn # ← ATAN (DWSn) in Table 2 indicates that the internal angles ATAN (DWS1 to DWS4) radially (RAD) of the corners C1 to C4 are substituted in the variables R1 # to R4 #, respectively.

In Table 2, aR ← (R1 # + R2 # + R3 # + R4 #) / 4.0 indicates that the average value of the internal angles ATAN (DWS1 to DWS4) radiated (RAD) to the variable aR is substituted have. In Table 2, Rn? Rn # -aR indicates that the values obtained by subtracting the variable aR from the variables R1 # to R4 # are substituted for the variables R1 to 4, respectively.

Thus, an error is included in the measurement value of the internal angle of the standard glass plate for calibration 36, and the sum of the measured values of the internal angles of the standard glass plate 36 for correction R1 # + R2 # + R3 # + R4 # R1 + R2 + R3 + R4 becomes zero as described below.

(R1 # -aR) + (R2 # -aR) + (R3 # -aR) + (R4 # -aR)

= R1 # + R2 # + R3 # + R4 # -4 x aR

= 0

In the above process, when at least one of | R3 + R4 |> 0.000001 or | AR12 |> 0.000001 is not satisfied, R3 * and R4 * are all set to zero. If at least one of | R1 + R2 |> 0.000001 or | AR12 |> 0.000001 is not satisfied, R1 * and R2 * are all set to zero.

The above processing is performed on the assumption that the standard glass plate 36 for correction is a rough parallelogram, and the difference between the lengths of the feces is a difference between the angles of both ends of the sides to be compared The difference is proportionally distributed to the original value of the angle so that the difference between the lengths between the long sides and the length between the short sides is corrected so that the difference in the lengths of the sides is reflected in the right angle.

By this processing, the approximate correction angles R1 * to R4 * are calculated and stored in the storage means 12b.

Next, the image processing apparatus 12 controls each illumination means 16 so as to illuminate the four corners of the standard glass plate for correction. At the same time, each of the image pickup means 18C0 to 18C3 is controlled so as to pick up an image including the corners C1 to C4 at each of the four corners of the standard glass plate for correction.

Each illuminating means 16 is turned on under the control of the image processing apparatus 12 to illuminate four corners of the standard glass plate for correction 36. [ Each of the imaging units 18C0 to 18C3 captures images P1 to P4 including the corners C1 to C4 of each of the four corners of the standard glass plate for correction 36 under the control of the image processing apparatus 12 (Step S12). 5 is an example of images P1 to P4 captured by the respective imaging units 18C0 to 18C3. The captured images P1 to P4 are introduced into the image processing apparatus 12. [

Subsequently, the image processing apparatus 12 calculates corner post-coordinates (hereinafter, referred to as CP coordinates (hereinafter referred to as " CP coordinates ") as coordinate values converted in mm from the image origin of each of the four corners of the standard glass plate 36 for correction, (Hereinafter referred to as CC dimensions) C1LX to C4LX and C1LY to C4LY (steps S14 and S16).

For example, by performing predetermined image processing on each of the images P1 to P4, each edge (horizontal edge EH, vertical edge EV, and slope edge EB) is detected as shown in Fig. 5 and horizontal and vertical edges EH , An intersection of the EV and the slope edge EB is obtained (step S14). The CP coordinates C1PX to C4PX, C1PY to C4PY, and CC dimensions C1LX to C4LX and C1LY to C4LY are calculated based on these intersections or the like (step S16).

Subsequently, the image processing apparatus 12 calculates the CP coordinates C1PX to C4PX, C1PY to C4PY of the calculated standard glass plate for calibration 36, the coordinates of each of the four sides of the standard glass plate 36 for calibration stored in the storage means 12b Based on the previously measured length dimensions E1, E2, ER and EL and the approximate correction angles R1 *, R2 *, R3 * and R4 * stored in the storage means 12b, the relative positions of the respective four imaging means 18C0 to 18C3 The coordinates S0 to S3 are calculated and stored in the storage means 12b (step S18).

More specifically, the relative coordinates S0 to S3 of each of the four imaging units 18C0 to 18C3 are calculated using the equations shown in Table 4 below.

By the above process, the relative coordinates S0 to S3 of each of the four imaging units 18C0 to 18C3 are calculated and stored in the storage unit 12b. FIG. 8 shows the relative coordinates S0 to S3 and the approximate correction angles R1 * and R2 * of the four imaging units 18C0 to 18C3, respectively.

[Measurement method of outer shape of work glass plate]

Next, a method for measuring the outer shape of the work glass plate 34 that is transported to pass through the shape measuring section 32 using the shape measuring apparatus 10 having the above-described configuration will be described with reference to FIG. 9 is a flowchart for explaining a method of measuring the contour shape of the work glass plate 34. Fig. The following processing is realized by the image processing apparatus 12 (calculation / control means) executing a predetermined program read into the storage means 12b or the like. It is assumed that the relative coordinates S0 to S3 of each of the four imaging units 18C0 to 18C3 are previously stored in the storage unit 12b. The stored relative coordinates S0 to S3 are obtained by reading the previously stored relative coordinates S0 to S3 from the storage means 12b and using the stored relative coordinates S0 to S3 as long as the arrangements of the imaging means 18C0 to 18C3 are the same as before It is possible. That is, as long as the arrangements of the imaging units 18C0 to 18C3 are the same as before, the previously stored relative coordinates S0 to S3 can be reused, and it is not necessary to perform the steps S10 to S18 every time.

First, the image processing apparatus 12 determines whether or not the work glass plate 34 has reached the measurement section 32 (step S20). When the image processing apparatus 12 determines that the work glass plate 34 to be measured reaches the measurement section 32 (the predetermined image pickup position) (step S20: Yes) When receiving the detection signal indicating that the end edge 34a (edge) in the carrying direction of the glass plate 34 is detected, the four corners of the work glass plate 34 reaching the measurement section 32 are illuminated And controls the lighting means 16. At the same time, each of the image pickup means 18C0 to 18C3 is controlled so as to pick up an image including the corners C1 to C4 at four corners of the work glass plate 34. [

Each illuminating means 16 is turned on under the control of the image processing apparatus 12 to illuminate the four corners of the work glass plate 34. Each of the image pickup means 18C0 to 18C3 is controlled by the image processing apparatus 12 so that the images p1 to p4 including the corner portions C1 to C4 at four corners of the work glass plate 34 (The same image as the illustrated images P1 to P4) (step S22). The captured images p1 to p4 are introduced into the image processing apparatus 12. [

Subsequently, the image processing apparatus 12 calculates CP coordinates c1Px to c4Px, c1Py to c4Py, and CC dimensions c1Lx to c4Lx, c1Ly to c4Ly, c1Lx to c4Lx, and c1Lx to c4Lx, respectively, of the four corners of the work glass plate 34 based on the captured images p1 to p4 (Steps S24 and S26).

For example, by performing predetermined image processing on each of the images p1 to p4, each edge (horizontal edge EH, vertical edge EV, slope edge EB) is detected in the same manner as shown in Fig. 5, EH, EV and the slope edge EB (step S24). CP coordinates c1Px to c4Px, c1Py to c4Py, and CC dimensions c1Lx to c4Lx and c1Ly to c4Ly based on these intersections and the like (step S26).

Subsequently, the image processing apparatus 12 calculates the position of the work glass plate 34 based on the CP coordinates c1Px to c4Px, c1Py to c4Py of the calculated work glass plate 34 and the relative coordinates S0 to S3 stored in the storage means 12b. E2, ER, and EL of each of the four sides of the memory unit 12b, and stores them in the storage unit 12b (step S28).

More specifically, the length dimensions E1, E2, ER, and EL of each of the four sides of the work glass plate 34 are calculated using the following equations.

The length dimensions E1, E2, ER and EL of each of the four sides of the work glass plate 34 are calculated by the above process and stored in the storage means 12b.

Subsequently, the image processing apparatus 12 calculates the distance between the calculated CP coordinates c1Px to c4Px, c1Py to c4Py, the relative coordinates S0 to S3 stored in the storage means 12b and the calculated length dimensions E1, E2, ER and EL And calculates the rectangular angles ∠1 to ∠4 of each of the four corners of the work glass plate 34 (step S28).

More specifically, the following equations are used to calculate the internal angles r1 to r4 of the respective corner portions of the work glass plate 34 in the form of radialization (RAD), and the work glass plate 34 is calculated based on the internal angles r1 to r4, The angles? 1 to? 4 of each of the four corners of the rectangle.

By the above process, the rectangular angles ∠1 to ∠4 of each of the four corners of the work glass plate 34 are calculated and stored in the storage means 12b.

Subsequently, the image processing apparatus 12 calculates the lengths E1, E2, ER, EL, and the rectangular angles ∠1 to ∠4 of each of the four sides of the calculated work glass plate 34 and predetermined standard values E2, ER, EL and the rectangular angles? 1 to? 4 are within a standard value (setting range), that is, whether or not the calculated lengths E1, E2, (Step S30). If the calculated length dimensions E1, E2, ER, and EL and the rectangular angles? 1 to? 4 are within the standard value (setting range) (step S30: Yes), the image processing apparatus 12 proceeds to step S20 And the processing of steps S20 to S30 is repeated with respect to the work glass plate 34 which has reached the measuring section 32 next. That is, for each of the plurality of work glass plates 34 (see FIG. 3) carried on the measurement line 30, the shape is measured non-stop. On the other hand, if the calculated length dimensions E1, E2, ER, EL and the rectangular angles ∠1 to ∠4 are not within the setting range (step S30: "NO"), the image processing apparatus 12 displays an alarm or the like on the display 22 So as to notify the effect.

As described above, according to the method of measuring the external shape of the work glass plate of the present embodiment, the image pickup means 18C0 to 18C3 are arranged in correspondence with the four corners of the work glass plate 34 in advance, (Or almost simultaneously) by the four imaging units 18C0 to 18C3 of the four corners of the work glass plate 34. The picked-up images p1 to p4 (The length dimension of each of the four sides of the work glass plate 34 and the squareness of each of the four corners of the rectangular plate-like object) of the work glass plate 34 (steps S20 to S28). This makes it possible to non-stop the shape measurement of each of the plurality of work glass plates 34 (see FIG. 3) carried on the measurement line 30, thereby making it possible to improve the yield.

Further, according to the method of measuring the outer shape of the work glass plate of the present embodiment, by using the (standard) calibration standard glass plate 36 in which the length dimensions of each of the four sides and the rectangular angle of each of the four corners are measured in advance, (The length dimension of each of the four sides of the work glass plate 34 and the rectangular angle of each of the four corners) of the workpiece 34 (the work glass plate 34) .

In addition, according to the method for measuring the contour shape of the work glass plate of the present embodiment, since the step S10 for correcting the pre-measured orthogonality of each of the four corners of the standard glass plate for correction 36 is provided, Even if measurement errors are included in the length dimension of each of the four sides of the glass plate 36 and the rectangular angle of each of the four corners, the measurement error is canceled. This makes it possible to calculate the relative coordinates of each of the four imaging units 18C0 to 18C3 with higher accuracy.

Next, modified examples will be described.

In the above embodiment, the measurement object is the standard glass plate 36 or the work glass plate 34 having four corners cut as shown in Fig. 5, but the present invention is not limited to this. For example, even if a standard glass plate 36 or a work glass plate 34 having no four corners cut off as shown in Fig. 3 or the like is used, CP coordinates C1PX to C4PX, C1PY to C4PY, E0, E2, ER, EL of each of the four sides of the work glass plate 34, and the perpendicular angle ∠1 of each of the four corners of the work glass plate 34 It is possible to calculate? 4.

In the above-described embodiment, an example in which the object to be measured is a glass plate subjected to a cutting process, a chamfering process, and a cleaning / drying process has been described. However, the present invention is not limited to this. For example, the glass plate before the cutting process, the glass plate before the chamfering process after the cutting process, and the glass plate before the cleaning and drying process after the chamfering process can be measured.

In the above embodiment, the relative coordinates S0 to S3 of each of the four imaging units 18C0 to 18C3 are calculated by the processes of steps S10 to S18, but the present invention is not limited to this. For example, if the relative coordinates S0 to S3 of each of the four imaging units 18C0 to 18C3 are measured in advance, the outer shape of the work glass plate 34 may be determined using the previously measured relative coordinates S0 to S3 (Steps S20 to S32).

Further, in the above-described embodiment, an example in which the rectangular plate-shaped object to be measured is a glass plate is described, but the present invention is not limited to this. The present invention can be similarly applied to other rectangular plate shaped articles such as wooden plates, metal plates and resin plates.

The foregoing embodiments are merely illustrative in all respects. The present invention is not limited to these descriptions. The present invention may be embodied in other forms without departing from the spirit or essential characteristics thereof.

While the present application has been described in detail with reference to specific embodiments thereof, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the invention.

The present application is based on Japanese Patent Application (Japanese Patent Application No. 2009-035732) filed on February 18, 2009, the content of which is incorporated herein by reference.

10: Shape measuring device
12: Image processing device
12a: calculation / control means
12b: storage means
14: LED Power
16: Lighting means
20: Sensor
30: Measurement line
32: Measurement section
34a: end edge
36: Standard glass plate for calibration
C1-C4: Corner portion

Claims (4)

A rectangular shape which is conveyed so as to pass through the shape measuring section is formed by using a shape measuring device including four imaging means previously arranged corresponding to the four corners of the rectangular plate shaped article and storing means for storing the relative coordinates of each of the four imaging means A measuring method for measuring an outer shape of a plate-like object,
Determining whether the rectangular plate-shaped article has reached the measurement section,
Capturing an image including corners of each of the four corners of the rectangular plate-like object which has reached the measurement section by the four imaging means when it is determined that the rectangular plate-shaped object has reached the measurement section;
Calculating a corner post coordinate, which is a coordinate value from an image origin of each of the four corners of the rectangular plate-like object, based on the captured image;
Calculating a length dimension of each of the four sides of the rectangular plate-like object on the basis of the calculated post-coordinates of the rectangular plate-shaped object and the relative coordinates stored in the storage means;
Calculating a squareness of each of the four corners of the rectangular plate-shaped object based on the calculated corner post coordinates, the relative coordinates stored in the storage means, and the calculated length dimension;
And a pre-measured squareness of each of the four corners of each of the four corners of the orthodontic standard rectangular plate, and a pre-measured squareness of each of the four corners of the standard rectangular plate for calibration, A step of correcting the squareness,
A step of photographing an image including corner portions of four corners of the standard rectangular plate for calibration by the four imaging means;
Calculating corner post coordinates of each of the four corners of the standard rectangular plate for calibration on the basis of the picked-up image;
Calculating relative coordinates of each of the four imaging units based on the calculated corner post coordinates of the standard rectangular plate for calibration, the corrected rectangular angles, and pre-measured length dimensions of each of the four sides of the standard rectangular plate for calibration And the step of storing in the storage means
And measuring the shape of the rectangular plate-shaped object. A rectangular shape which is conveyed so as to pass through the shape measuring section is formed by using a shape measuring device including four imaging means previously arranged corresponding to the four corners of the rectangular plate shaped article and storing means for storing the relative coordinates of each of the four imaging means A measuring method for measuring an outer shape of a plate-like object,
Determining whether the rectangular plate-shaped article has reached the measurement section,
Capturing an image including corners of each of the four corners of the rectangular plate-like object which has reached the measurement section by the four imaging means when it is determined that the rectangular plate-shaped object has reached the measurement section;
Calculating a corner post coordinate, which is a coordinate value from an image origin of each of the four corners of the rectangular plate-like object, based on the captured image;
Calculating the length dimension of each of the four sides of the rectangular plate-like object on the basis of the calculated corner post coordinates of the rectangular plate-shaped object and the relative coordinates stored in the storage means;
Calculating a squareness of each of the four corners of the rectangular plate-shaped object based on the calculated corner post coordinates, the relative coordinates stored in the storage means, and the calculated length dimension;
A step of comparing the calculated length dimension and the squareness with a predetermined standard value,
A step of judging a defect of the contour of the rectangular plate-shaped object based on the comparison result;
And a pre-measured squareness of each of the four corners of each of the four corners of the orthodontic standard rectangular plate, and a pre-measured squareness of each of the four corners of the standard rectangular plate for calibration, A step of correcting the squareness,
A step of photographing an image including corner portions of four corners of the standard rectangular plate for calibration by the four imaging means;
Calculating corner post coordinates of each of the four corners of the standard rectangular plate for calibration on the basis of the picked-up image;
Calculating relative coordinates of each of the four imaging units based on the calculated corner post coordinates of the standard rectangular plate for calibration, the corrected rectangular angles, and pre-measured length dimensions of each of the four sides of the standard rectangular plate for calibration And the step of storing in the storage means
And measuring the shape of the rectangular plate-shaped object. There is provided a method of calibrating the relative coordinates of the four imaging means in a shape measuring apparatus including four imaging means arranged in advance corresponding to four corners of a rectangular plate-
And a pre-measured squareness of each of the four corners of each of the four corners of the orthodontic standard rectangular plate, and a pre-measured squareness of each of the four corners of the standard rectangular plate for calibration, A step of correcting the squareness,
A step of photographing an image including corner portions of four corners of the standard rectangular plate for calibration by the four imaging means;
Calculating corner post coordinates of each of the four corners of the standard rectangular plate for calibration on the basis of the picked-up image;
Calculating relative coordinates of each of the four imaging units based on the calculated corner post coordinates of the standard rectangular plate for calibration, the corrected rectangular angles, and pre-measured length dimensions of each of the four sides of the standard rectangular plate for calibration Step
And correcting the relative position of the imaging means. delete

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