KR20080060027A - Test apparatus for liquid crystal display - Google Patents

Abstract

A test apparatus for an LCD(Liquid Crystal Display) is provided to prevent light leakage at an inverse pattern by adding a barrel in a front end of an existing VAP(Vision Auto Probe) camera, thereby detecting faults by testing all of nine test patterns necessary for detection force. An auto probe unit is for applying a test signal to an LC panel. A light source irradiates light to the LC panel. Plural cameras(110a~110d) receive the test signal and the light, and obtain information about an image implemented on the LC panel. Light interference removing units(120a~120d) are respectively fastened with the plural cameras and remove light interference between the plural cameras.

Description

Test apparatus for liquid crystal display {Test apparatus for liquid crystal display}

1 is a view showing the appearance of a vision auto probe inspection device having four cameras according to the prior art.

FIG. 2 is a diagram illustrating a screen inspected by the inspection apparatus of FIG. 1. FIG.

3A to 3C are diagrams illustrating the appearance of light leakage light reflection in a test pattern.

4 is a view showing the appearance of a vision auto probe inspection device having four cameras according to an embodiment of the present invention.

5 is a diagram illustrating a vision auto probe inspection device.

FIG. 6 is a diagram illustrating an optical information processor of FIG. 5.

7 is a view for explaining the principle of failure detection of the liquid crystal panel.

8 is a diagram illustrating nine vision auto probe test patterns.

9A to 9C are diagrams illustrating that light leakage light reflection is removed according to an embodiment of the present invention.

<Explanation of symbols on main parts of the drawings>

100: vision auto probe inspection device 110a, 110b, 110d, 110d: CCD camera

120a, 120b, 120c, 120d: Tube 200: Auto probe checker

The present invention relates to an inspection apparatus for a liquid crystal display device.

In general, a liquid crystal display (LCD) is a flat panel display that displays an image by adjusting a transmission amount of a light beam to correspond to an image signal.

The manufacturing process for manufacturing the liquid crystal display device is divided into a substrate cleaning process, a substrate patterning process, an alignment film forming and rubbing process, a substrate bonding and liquid crystal injection process, an inspection process, a repair process and a mounting process.

In the substrate cleaning process, foreign substances contaminated on the substrate surface of the liquid crystal display device are removed with the cleaning liquid.

In the substrate patterning process, the patterning is divided into the patterning of the color filter substrate, which is the upper substrate, and the patterning of the TFT array substrate, which is the lower substrate. On the upper plate, a color filter, a common electrode, a black matrix, and the like are formed. A signal line such as a data line and a gate line is formed on the lower plate, a TFT is formed at an intersection of the data line and the gate line, and a pixel electrode is formed in the pixel region between the data line and the gate line connected to the source electrode of the TFT. do.

In the alignment film forming and rubbing process, an alignment film is applied to each of the upper substrate and the lower substrate, and the alignment film is rubbed with a rubbing cloth or the like.

In the substrate bonding and liquid crystal injection process, the upper substrate and the lower substrate are bonded using a sealant, the liquid crystal is injected through the liquid crystal injection hole, and then the liquid crystal main inlet is sealed.

In addition, the inspection process includes an electrical inspection performed after various signal wires and pixel electrodes are formed on the lower substrate, and electrical inspection and visual inspection performed after the substrate bonding and liquid crystal injection processes.

The repair process repairs a substrate determined to be repairable by the inspection process described above, while discarding defective substrates that cannot be repaired in the inspection process.

In the liquid crystal panel mounting process, a tape carrier package (TCP) in which integrated circuits such as a gate drive integrated circuit and a data drive integrated circuit are mounted is connected to a pad portion on a substrate.

On the other hand, in the conventional liquid crystal panel inspection method using an auto probe tester, since the defective pixel of the liquid crystal panel is visually measured, an error occurs in the inspection result depending on the health state of the operator and the eye state. In particular, the visual inspection method has a high degree of fatigue with respect to direct sunlight, so that the light generated from the backlight during the liquid crystal panel inspection increases the visual fatigue of the operator. Accordingly, there is a problem that the test results are not uniform and the reliability of the test results is lowered.

To address this, Vision Auto Probe (VAP), which combines an auto probe device and a vision system, has been introduced.

1 is a view showing the appearance of a vision auto probe inspection device having four cameras according to the prior art.

In the case of the currently applied vision auto probe inspection, as shown in FIG. 1, when four cameras 11a, 11b, 11c, and 11d are used, there is a problem in that a pattern inspection for inverted bright point detection cannot be performed. That is, in the case of the conventional vision auto probe inspection, when four cameras 11a, 11b, 11c, and 11d are used, the white portion of the pattern is reflected by the camera in the inspection split pattern, or light leakage occurs. There is a problem that not all the pattern checks can be performed.

Specifically, FIG. 2 is a diagram illustrating a screen inspected by the inspection apparatus of FIG. 1, in which a reflection phenomenon occurs on the screen 20 as indicated by reference numeral A, and as shown by reference numeral B. As shown in FIG. Light leakage occurs.

FIG. 3A shows the phase inversion screen for the inversion bright point inspection, FIG. 3B shows the light leakage phenomenon as shown by reference numeral C, and FIG. 3C shows the reflection phenomenon as indicated by reference numeral D. FIG. Therefore, the conventional vision auto probe test has a problem in that all nine pattern tests cannot be performed because light leakage occurs.

SUMMARY OF THE INVENTION An object of the present invention for solving the above-described problems is to provide an inspection apparatus for a liquid crystal display device capable of performing all nine pattern inspections by performing a pattern inspection for inverting bright point detection.

The objects of the present invention are not limited to the above-mentioned objects, and other objects that are not mentioned will be clearly understood by those skilled in the art from the following description.

In order to achieve the above technical problem, an inspection apparatus for a liquid crystal display device according to the present invention, the automatic probe unit for applying a test signal to the liquid crystal panel; A light source for irradiating light onto the liquid crystal panel; A plurality of cameras receiving the inspection signal and the light to obtain information about an image implemented on the liquid crystal panel; And an optical interference canceling unit coupled to each of the plurality of cameras to remove optical interference between the plurality of cameras.

Here, the optical interference canceling unit is fastened to surround the lens unit of the front end of the camera.

The optical interference canceling unit may be a barrel, and the barrel surrounds the lens unit of the front end of the camera and extends by a predetermined length in the imaging direction of the camera.

Here, the camera may be a color charge coupled device (Charge Coupled Device) camera, the plurality of cameras are characterized in that four units are installed, two each up and down.

Here, the barrel is coupled to at least two or more of the four cameras.

Specific details of other embodiments are included in the detailed description and the drawings. Advantages and features of the present invention and methods for achieving them will be apparent with reference to the embodiments described below in detail with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but may be embodied in various forms, and the present embodiments are merely provided to make the disclosure of the present invention complete and the general knowledge in the art to which the present invention belongs. It is provided to fully inform the person having the scope of the invention, the invention is defined only by the scope of the claims.

Hereinafter, an inspection apparatus for a liquid crystal display according to an exemplary embodiment of the present invention will be described in detail with reference to the accompanying drawings.

4 is a view showing the appearance of a vision auto probe inspection device having four cameras according to an embodiment of the present invention.

Referring to FIG. 4, an inspection apparatus for a liquid crystal display according to an exemplary embodiment of the present invention may include an auto probe unit (not shown), a light source (not shown), a plurality of cameras 110a, 110b, 110c, and 110d. And optical interference canceling parts 120a, 120b, 120c, and 120d.

The auto probe unit applies an inspection signal to the liquid crystal panel, and the light source is a backlight unit, and emits light to the liquid crystal panel. In addition, a light sheet stacked between the light source and the liquid crystal panel may diffuse the light generated from the light source and convert the emission angle of the diffused light.

The plurality of cameras 110a, 110b, 110c, and 110d receive information about the image implemented on the liquid crystal panel by receiving the inspection signal and the light. In the embodiment of the present invention, the plurality of cameras 110a, 110b, 110c, and 110d are color charge coupled device cameras, and four of them are installed on the plane of the inspection apparatus. As described above, since four cameras 110a, 110b, 110c, and 110d are installed, optical interference may occur between the cameras 110a, 110b, 110c, and 110d, and thus reflection and light leakage may occur. . Accordingly, the plurality of cameras 110a, 110b, 110c, and 110d are fastened to the optical interference cancellers 120a, 120b, 120c, and 120d.

The optical interference cancellers 120a, 120b, 120c, and 120d are fastened to the plurality of cameras 110a, 110b, 110c, and 110d, respectively, to provide light between the plurality of cameras 110a, 110b, 110c, and 110d. This will eliminate interference. In this case, the optical interference removing unit 120a, 120b, 120c, or 120d may be a barrel that is fastened to surround the lens unit in front of the cameras 110a, 110b, 110c, and 110d. The barrels 120a, 120b, 120c, and 120d surround the lens portion in front of the cameras 110a, 110b, 110c, and 110d and extend by a predetermined length in the imaging direction of the cameras 110a, 110b, 110c, and 110d. Is formed.

Here, the barrels 120a, 120b, 120c, and 120d may be coupled to at least two or more of the four cameras 110a, 110b, 110c, and 110d, and in the embodiment of the present invention, four cameras 110a, 110b, 110c, and 110d).

FIG. 5 is a diagram illustrating a vision auto probe inspection device, and FIG. 6 is a diagram illustrating the optical information processor of FIG. 5.

Referring to FIG. 5, an inspection apparatus for a liquid crystal display device includes an optical information processing unit 100 for acquiring and processing information about an object, and an auto probe inspector for mounting an object and applying a signal to face the optical information processing unit 100. 200).

As shown in FIG. 6, the optical information processing unit 100 includes a CCD (Charge Coupled Device) camera 110 for acquiring information on the liquid crystal panel and a movement control means for moving the CCD camera 110 up, down, left, and right ( 130 and an information processing unit 140 for processing information obtained from the CCD camera 110.

The CCD camera 110 may selectively use a line camera that scans a liquid crystal panel for each line for inspection and an area camera that can scan a liquid crystal panel for a predetermined area.

The CCD camera 110 captures an image of a liquid crystal panel in 1000 frame / sec units.

Shanghaidong of the movement control means 130 adjusts the focus of the object and the CCD camera 110, the left and right movement of the movement control means 130 is a CCD when the CCD camera 110 is operated to scan the object The camera 110 is moved left and right.

The information processing unit 140 displays vision hardware (Vision H / W) 141 for processing the information transmitted from the CCD camera 110 into an image that can be checked by an operator, and displays an image processed through the vision hardware 141. The image display unit 142 and a defect map 143 for displaying a defect on the liquid crystal panel to be inspected may be provided.

On the other hand, Figure 7 is a view for explaining the principle of failure detection of the liquid crystal panel.

Referring to FIG. 7, the defect detection of the liquid crystal panel is to detect spot defects (PD), foreign objects, and line defects of the liquid crystal panel unattended, and detects the local luminance difference between the defective part and the normal part and displays them as candidate points. do. That is, the luminance difference between the bright point having a higher luminance value relative to the surroundings and the dark point having a lower luminance value than the surroundings is detected and displayed as a candidate point based on the reference luminance value (Threadhold).

8 is a diagram illustrating nine vision auto probe test patterns.

Referring to FIG. 8, there are a total of nine patterns of the vision auto probe test pattern used to detect a defect. That is, the pattern includes a black pattern, a first upper inversion pattern 141, a second upper inversion pattern 142, a red pattern, a green pattern, a blue pattern, a front side metering pattern, a first back side metering pattern, and a second back side metering pattern.

In the inspection of the two spot pattern (141, 142) of the inspection pattern, in the conventional case, it was impossible to detect the defect due to the light leakage phenomenon or reflection phenomenon, in the case of the embodiment of the present invention, by adding a barrel to the front end of the existing VAP camera By preventing light leaks in the inversion pattern, defects can be detected by inspecting all nine inspection patterns required for detection power.

9A to 9C are diagrams illustrating that light leakage light reflection is removed according to an embodiment of the present invention.

FIG. 9A illustrates the phase inversion pattern 141 among the nine patterns described above. FIG. 9B illustrates that light leakage is removed, and FIG. 9C illustrates that reflection is removed. That is, in the case of a VAP equipped with four existing area cameras, the white pattern is reflected by the camera and detected as an image, thereby resulting in a split pattern, that is, 70% black and 30% white for inverted bright spot detection. Although the in-pattern inspection is not performed, in the embodiment of the present invention, by adding a barrel to the front end of the camera of the VAP, the inspection can be performed in all nine patterns.

Although embodiments of the present invention have been described above with reference to the accompanying drawings, those skilled in the art to which the present invention pertains may implement the present invention in other specific forms without changing the technical spirit or essential features thereof. I can understand that. Therefore, the embodiments described above are to be understood in all respects as illustrative and not restrictive.

According to the present invention, by removing the light leakage and reflection phenomenon, all nine pattern inspections can be performed by performing the pattern inspection for the inversion bright point detection.

Claims (7)

An auto probe unit for applying a test signal to the liquid crystal panel; A light source for irradiating light onto the liquid crystal panel; A plurality of cameras receiving the inspection signal and the light to obtain information about an image implemented on the liquid crystal panel; And An optical interference canceling unit coupled to the plurality of cameras to remove optical interference between the plurality of cameras Inspection device for a liquid crystal display comprising a. The method of claim 1, And the optical interference canceling unit is coupled to surround the lens unit at the front end of the camera. The method of claim 1, And said optical interference canceling portion is a barrel. The method of claim 3, And the barrel surrounds the lens portion of the front end of the camera and extends by a predetermined length in the imaging direction of the camera. The method of claim 1, And the camera is a color charge coupled device camera. The method of claim 1, And a plurality of cameras, two each of which is provided at an upper side and a lower side of the plurality of cameras. The method of claim 6, And the barrel is coupled to at least two or more of the four cameras.

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