TWM601821U - Split position inspection device for liquid crystal glass substrate - Google Patents

Abstract

A device for inspecting the split position of a liquid crystal glass substrate, comprising: a camera with a Sham telecentric lens to shoot from the outer side of the liquid crystal glass substrate obliquely above; an illumination device that illuminates from the inner side of the liquid crystal glass substrate obliquely above; and an image processing device, From the split surface image of the liquid crystal glass substrate illuminated by the lighting device captured by the camera, the shadow part caused by the height difference of the substrate is identified. In the liquid crystal panel manufacturing process, in the step of dividing the end material of the CF glass of the liquid crystal glass substrate, the dividing position inspection device of the liquid crystal glass substrate provided by the present invention can improve the accuracy of the judgment device of the camera in judging the condition of the end material division .

Description

Split position inspection device for liquid crystal glass substrate

This creation is about a device for checking the dividing status of the liquid crystal glass substrate in the cutting step of the liquid crystal glass substrate in the manufacture of liquid crystal panels, and more specifically about the dividing position inspection of the liquid crystal glass substrate to improve the judgment accuracy of the judgment device using a camera Device.

As shown in FIG. 5(A), the liquid crystal glass substrate a is constructed by laminating two substrates of TFT glass b and CF glass c. The glass cut surface produced by the cutting step of the liquid crystal glass substrate a further has the following step: cutting the peripheral end material of the CF glass c to expose the electrode part (not shown) existing on the TFT glass b.

As shown in Figure 5(B), the following method is used for cutting CF glass: In the cutting process, the CF glass c is cut into a crack V by cutting, and then pressure is applied to the CF glass c to make the CF glass The end material X of c is completely divided as shown in Fig. 5(C).

At this time, as shown in the plan view of the liquid crystal glass substrate a shown in FIG. 6(A), there is no problem if the end material X is in a normal divided state. However, when the crack depth of CF glass c is inappropriate, or the starting point of pressure or the amount of pressure is not appropriate, the cross-section of CF glass c will not break as expected, but will produce as shown in Figure 6 (B) The end material is excessively removed (see notch Y), or as shown in Figure 6 (C), a part of the end material defect remains (see protrusion, end material residue Z).

The aforementioned defects are not only product defects, but also sometimes cause damage to devices in subsequent processes. Therefore, the measurement of the cut part of CF glass is an important inspection item.

An inspection device with the device configuration shown in Figure 7 is often used as a device for detecting the aforementioned defects. In other words, the liquid crystal glass substrate a is placed on the platform 13 with the TFT glass b on the lower side and the CF glass c on the upper side, and a camera 15 is provided. The camera 15 uses a telecentric lens 14 for coaxial illumination and Assembled with lighting 16. In addition, the camera 15 images the exposed terminal portion of the TFT glass b with the end material removed in the CF glass c from directly above. Then, the captured image passes through the image processing device 17 to confirm the position of the cut edge of the CF glass c.

The so-called telecentric lens 14 is a lens whose image magnification does not change with the distance of the subject, so it is suitable for measuring the size of the aforementioned end material removal part (the distance from the end of TFT glass b to the end of CF glass c ).

If the camera using this device observes the terminal portion of the liquid crystal glass from directly above, the cross section of the CF glass c is actually almost vertical, so there may be cases where the captured image has almost no width or is completely unrecognizable. As shown in the image taken in Fig. 8, it can be seen that it is sometimes difficult to measure the edge c′ of the CF glass c, and it is difficult to judge whether the division is normal or defective.

As shown in Fig. 9, in the past, in order to solve the above-mentioned problem, the light irradiated from the illuminating 16 obliquely was used to capture the diffuse reflection of the CF glass c section. However, light does not reflect in the direction of the camera, and the glass cross-sections are not necessarily at the same angle. Even if there are internal gaps or protrusions (end material remaining), the dividing line of the CF glass c cannot be taken stably. Therefore, such a method cannot be described as high reliability, and the stability of detection is not sufficient.

In view of this, various proposals or improvements have been made (please refer to Patent Documents 1 to 3) , It uses images to detect defects in the glass cut surface.

[ Prior Art Document ] [Patent Document] Patent Document 1: International Publication WO2012/153718; Patent Document 2: Japanese Patent Application Publication No. 2001-153816; Patent Document 3: Japanese Patent Application Publication No. 2005-156254.

[ Problem to be solved ] Although there have been proposals or improvements shown in the aforementioned Patent Documents 1 to 3, Patent Document 1 captures the light reflected from the inside of the glass at the end of the glass and inspects it accordingly, not for determining CF Whether the end material of the glass is the dividing position of the normal division.

However, Patent Document 2 or Patent Document 3 considers the occurrence of defects on the edge of the glass cutting surface and detects with a specific illuminance. For defects or protrusions that are not assumed, and where the end material remains, the measurement accuracy is considered to be inferior. enough.

Furthermore, in Patent Document 1 or Patent Document 3, the camera is inclined with respect to the glass substrate. As a result, it is not suitable for measuring the correct division position of the end material removal portion.

In order to solve the above-mentioned problems, the purpose of this creation is to provide a device for inspecting the split position of liquid crystal glass substrates, which uses a camera to determine the splitting of the end materials during the CF glass end material splitting process of the liquid crystal glass substrate during the liquid crystal panel manufacturing process. Condition determination device to improve accuracy.

[ Means to Solve the Problem ] In other words, in order to solve the above problems, this creation provides a device for inspecting the split position of a liquid crystal glass substrate, including: a table, which carries the lower surface of the liquid crystal glass substrate, and the upper surface of the liquid crystal glass substrate is divided Manufacturing process; holding the suction means, holding the liquid crystal glass substrate carried on the table; the camera, which has a Scheimpflug telecentric lens, and is arranged on the outside of the edge of the table, and diagonally above the outside of the liquid crystal glass substrate , Shooting the split surface of the liquid crystal glass substrate; the lighting device, which illuminates the split surface of the liquid crystal glass substrate from the inner side of the liquid crystal glass substrate obliquely above; and the image processing device, shooting from the camera to the split surface of the liquid crystal glass substrate illuminated by the lighting device In the surface image, the shadow part caused by the height difference of the substrate is recognized.

This creation is not to set the camera obliquely and make the CF glass section diffuse reflection by counter-illumination, but uses the following method: make the shadow part and detect it with the camera, so that the end of the CF glass can be reliably detected. Width, so that it is possible to reliably take pictures and detect the notch or protrusion (end material remaining) in the removal width (division position) that exceeds the specified value.

As far as the lens of a general camera is concerned, since the distant objects are small and the close objects are large, when the lens is tilted, its focus is only on the center, and the magnification will vary depending on the position. It can be seen from this that general lenses are not suitable for length measurement purposes. Instead, telecentric lenses are often used for distance measurement. However, in this creation, the method described below is used to photograph the inspection part in an oblique direction using a Sham telecentric lens with an offset lens.

In other words, from the end of the CF glass in the field of view to the end of the TFT glass, in all the state of focus, and the magnification in the field of view is fixed, the shadow is generated by the oblique upward illumination, so that the shadow can be reliably recognized , To accurately check the split position of the CF glass in the glass section.

[ Effects of this creation ] As mentioned above, according to the split position inspection device of the liquid crystal glass substrate of this creation, it is possible to accurately determine the split position of the end material removal part of the CF glass by using the image of the camera; the detection is immediately detected Excessively removed gaps in the end material exceeding the specified limit, or a part of the end material protrusions and end material residues; rapid removal of defective products; and prevention of failures or accidents caused by defective products sent to the subsequent process in advance.

Next, the implementation of this creation will be explained based on the first and second figures.

Symbol 1 in Figure 1 is a table on which a liquid crystal glass substrate a is placed. The above-mentioned liquid crystal glass substrate a is held on the table 1 with the TFT glass b as the lower side and the CF glass c as the upper side.

As shown in the figure, the holding method is to use the hollow table 1. The inside of the table 1 is sucked through the hose (not shown) connected to the suction port 8, and the table 1 is sucked through the numerous small holes 3 provided on the top wall 2 of the table 1, thereby on the top wall 2. Keep sucking the carried liquid crystal glass substrate a. But this creation is not limited to this, other methods can also be used.

A camera 22 is arranged on the outer side of one edge of the table 1, and the camera 22 has a Sham telecentric lens 21. The camera 22 is obliquely above the outer side of the liquid crystal glass substrate a, and takes an image of the end material of the CF glass c at the end of the liquid crystal glass substrate a, with the split surface image removed.

The aforementioned Sham telecentric lens 21 is a telecentric lens whose image magnification does not change due to the distance from the subject, and the focal plane is inclined with respect to the lens axis. In this creation, you can first set the focal plane in an oblique direction from the end of the CF glass to the end of the TFT glass.

The lighting device 23 is installed from the camera 22 through the arm 10 so that the mutual positional relationship with the camera 22 remains unchanged. The illuminating device 23 illuminates the removed part of the CF glass c on the edge of the liquid crystal glass substrate a from the inner side of the liquid crystal glass substrate a diagonally upward.

As shown in Figure 2, with the aforementioned camera 22 (Sham telecentric lens 21) and the illuminating device 23, the image of the camera 22 is to capture the shadows formed by the illuminating device 23 on the TFT glass b and CF glass c. S part.

The camera 22 and the lighting device 23 are mounted on the base 4. Furthermore, by the moving means D, one of the table 1 or the camera 22 is moved forward and backward along the edge of the liquid crystal glass substrate a (the edge of the image taken).

Please refer to Figure 1 again for the aforementioned moving means D for forward and backward movement. As shown in the figure, on the underside of the seat plate 5 arranged under the base 4, two fixed guide rails 6 on the left and right are arranged in parallel. The guide rail 6 is slidably engaged with the sliders 7 provided at the four corners under the seat plate 5, and is freely rotated by bearings (not shown) at both ends, so that one end of the male screw 9 of the bearing is driven by a motor (not shown) ) Reversible drive. Next, the female screw 11 supported under the seat plate 5 is screwed into the male screw 9 to move the camera 22 and the illuminating device 23 forward and backward together with the base 4 in the front-rear direction. However, this creation is not limited to this, and the camera 22 and the lighting device 23 may be fixed, and the table 1 may be movable (forward and backward).

Although the forward and retreat movement method is performed by driving the male screw 9 screwed to the female screw 11, the present invention is not limited to this, for example, a linear motor method may be used. Alternatively, the stationary table 1 can be pre-installed on the seat material 12.

With the above configuration, the entire area on one side of the liquid crystal glass substrate a can be imaged by the camera 22 of the end material removal surface image of the CF glass c of the liquid crystal glass substrate a on the table 1.

As shown in Fig. 3, an image shot by the camera 22 (actually an image formed by successively combining the shot images) is disclosed. Among them, the shadow S formed by the lighting device 23 is different due to the low illuminance. If there is an inner notch Y, a protrusion or a residual part Z of the end material, the regular part will not produce a shadow S, so that the shape of the shadow S can be detected.

Next, a method for automatically determining whether the end material of the CF glass c is divided normally by using an image processing device (not shown) to automatically determine whether the end material of the CF glass c is normally divided by the image taken by the camera 22 of the present creation.

As shown in Figure 3, the part where the inner notch Y, protrusion, or end material remains Z is first generated, and the size from the end of TFT glass b to the end of CF glass is larger (see notch Y) or smaller (Please refer to protrusion, end material residual Z) specific size (assumed width of end material X).

Therefore, if the CF division length can be automatically obtained, the generation of the notches Y, protrusions, and end material residues Z can be detected.

Specifically, first, the angle between the incident angle of the light from the illuminating device 23 and the vertical direction is set as θ ₁ , and the angle between the shooting angle of the Sham telecentric lens 21 of the camera 22 and the vertical direction is set as θ ₂ .

And, as shown in Figure 4(A), the size from the end of the CF glass c (the boundary of the shadow S) obtained from the captured image to the end of the TFT glass b (the boundary of the shadow S) is set to l ₀ , and the shadow The width dimension of S itself is set to l ₁ .

[數2]

[數3]

As shown in Figure 4(B), the removal size W of CF glass c is obtained from the above θ ₁ , θ ₂ , l ₀ , and l ₁ , which is calculated by the following mathematical formula (number 1, number 2, number 3) Get: [Number 1]

[Number 2]

[Number 3]

[數5]

In addition, the position of the reference mark M on the TFT glass b shown in Fig. 4(A) is used as a reference, and the division position (wc) of the CF glass c and the division position of the TFT glass b ( wt), as shown in the following mathematical formula (number 4, number 5): [number 4]

[Number 5]

In summary, according to the dividing position inspection device of the liquid crystal glass substrate of the present invention, the dividing position of TFT glass or CF glass can be accurately determined with high accuracy, so that defects such as notches or protrusions can be easily detected.

a: Liquid crystal glass substrate b: TFT glass c: CF glass D: Means of movement S: shadow M: fiducial mark V: Crack X: End material Y: gap Z: Protrusion, end material residue 1: table 2: top wall 3: small holes 4: base 5: Seat plate 6: Rail 7: Slide 8: Suction port 9: male screw 10: arm 11: Female screw 12: Seat material 13: platform 14: Telecentric lens 15: Camera 16: lighting 17: Image processing device 21: Sham telecentric lens 22: Camera 23: lighting device

Figure 1 is a partially omitted side view, which discloses the implementation of the split position inspection device of the liquid crystal glass substrate of the present invention.

Figure 2 is an enlarged side view of an important part of the creation.

Figure 3 is an image taken by the inspection device created.

Figure 4 (A) and (B) are explanatory diagrams that illustrate the method of obtaining the CF division width from the image in Figure 3, where Figure 4 (A) is the captured image, and Figure 4 (B) is the side view of the calculation method Figure.

Figure 5 (A), (B) and (C) are front views, which reveal the process of separating the end material of CF glass from the liquid crystal glass substrate.

Figure 6 (A) is a plan view of a liquid crystal glass substrate with CF glass removed normally, and Figures 6 (B) and (C) are plan views of a liquid crystal glass substrate with defective CF glass removed.

Figure 7 is a front view, revealing a conventional device for inspecting the split position of a liquid crystal glass substrate.

Figure 8 is an image taken by a conventional liquid crystal glass substrate dividing position inspection device.

Fig. 9 is a front view showing a device for inspecting the split position of a liquid crystal glass substrate according to other embodiments of the prior art.

a: Liquid crystal glass substrate

b: TFT glass

c: CF glass

S: shadow

21: Sham telecentric lens

22: Camera

23: lighting device

Claims (1)

A device for inspecting the split position of a liquid crystal glass substrate, comprising: The table is the lower surface of the liquid crystal glass substrate, and the upper surface of the liquid crystal glass substrate has undergone a dividing process; Keep the suction means and keep the liquid crystal glass substrate carried on the table; A camera with a Sham telecentric lens, the camera is arranged on the outside of the edge of the table, and is obliquely above the outside of the liquid crystal glass substrate to photograph the split surface of the liquid crystal glass substrate; An illuminating device, which illuminates the dividing surface of the liquid crystal glass substrate from the inner side of the liquid crystal glass substrate obliquely upward; and The image processing device recognizes the shadow part caused by the height difference of the substrate from the image of the split surface of the liquid crystal glass substrate illuminated by the illumination device captured by the camera.

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