KR101232158B1 - The test process for Liquid Crystal Display Device - Google Patents

Abstract

An object of the present invention is to provide an inspection process of a liquid crystal display device that can accurately and quickly determine whether the LCD panel is defective.

To this end, the present invention is to cut a large glass substrate to produce a sheet of LCD panel; Loading the LCD panel into an LCD inspection apparatus having an imaging device such as a camera to inspect whether the LCD panel is defective; Removing the shorting bar formed on the LCD panel using a polishing machine; Cleaning the LCD panel from which the shorting bar is removed; In addition, an inspection process of the liquid crystal display device including the step of directly inspecting the cleaned LCD panel by an operator to determine whether or not the final failure.

According to the present invention as described above by taking an image of each pattern displayed on the LCD panel using an imaging device, such as a CCD camera, and by analyzing the captured image in the control unit to determine whether the LCD panel is defective or not Completion of inspection limitations can greatly improve work efficiency and accuracy.

LCD Inspection Equipment, Imaging Equipment, Laser Trimmer, Grinder, Inspection Process

Description

The test process for Liquid Crystal Display Device

1 is a flowchart illustrating an inspection process of a liquid crystal display according to a first embodiment of the present invention.

Figure 2 is a side cross-sectional view showing a schematic structure of the LCD inspection equipment according to the present invention.

3 is a plan view of a gate pad portion of an LCD panel according to the present invention.

4 is a plan view of a data pad portion of an LCD panel according to the present invention.

5 is a flowchart illustrating an inspection process of a liquid crystal display according to a second exemplary embodiment of the present invention.

Description of the Related Art [0002]

110: work table 120: probe unit

130: backlight unit 140: polarizing plate

150: moving stage 160: video equipment

200: gate shorting bar 300: data shorting bar

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a manufacturing process of a liquid crystal display device (LCD), and more particularly to an inspection process of a liquid crystal display device for inspecting whether an LCD panel is defective.

As the information society develops, the demand for display devices is increasing in various forms, and in recent years, liquid crystal display devices (LCDs), plasma display panels (PDPs), electro luminescent displays (ELDs), and vacuum fluorescent (VFD) Various flat panel display devices such as displays have been studied, and some of them are already used as display devices in various devices.

Among them, the liquid crystal display device is the most widely used as a substitute for the CRT (Cathode Ray Tube) for the mobile image display device due to the advantages of excellent image quality, light weight, thinness and low power consumption. In addition to the mobile use, such as a variety of TV and computer monitors that receive and display broadcast signals have been developed.

Such a liquid crystal display generally includes a thin film transistor array substrate having thin film transistors and pixel electrodes formed in each pixel region defined by gate wirings and data wirings, a color filter array substrate having color filter layers and a common electrode formed thereon, and the two substrates. It is composed of a liquid crystal layer interposed therebetween, by applying a voltage to the electrode to rearrange the liquid crystal molecules of the liquid crystal layer to adjust the amount of light transmitted to display an image.

In this case, the color filter array substrate and the thin film transistor array substrate are bonded by a sealant such as an epoxy resin, and a driving circuit on a printed circuit board (PCB) is connected to the thin film transistor array substrate.

Meanwhile, the LCD panel manufactured by combining the color filter array substrate and the thin film transistor array substrate as described above undergoes an inspection process for checking for defects.

Hereinafter, the inspection process of the liquid crystal display according to the prior art will be briefly described.

First, since the LCD panel manufactured by bonding the array substrate and the color filter substrate together is made of a large-area glass substrate, the LCD panel is cut into a single LCD panel.

That is, since a plurality of panel regions are formed on a large glass substrate, and thin film transistors and color filters are formed in each of the panel regions, a large glass substrate is cut by cutting a large glass substrate to individually inspect an LCD panel to be used in a real product. It must go through a cutting process to make a substrate.

Then, when a large glass substrate is cut and a single LCD panel is manufactured, each LCD panel is sent to the LCD inspection equipment to be inspected for various defects. In general, the LCD inspection apparatus inspects color filter protrusions, slanted spots, rubbing stripes, pinholes, gate lines, and data lines on the LCD panel.

However, the inspection process of the liquid crystal display device according to the prior art had the following problems.

First, the inspection of the LCD panel through the LCD inspection equipment whether the defect is made through the eyes of the operator has a problem that takes a long time to inspect a large amount of LCD panel.

In particular, in recent years, LCD panels have been gradually enlarged, so that there is a limit for the operator to perform all of the inspection of the LCD panels with the naked eye.

In addition, since defects are detected by visual inspection of the operator, defects such as point defects (PD), line defects (LD), and minute stains are not found, thereby increasing the reliability of the inspection results. There was a problem falling.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to provide an inspection process of a liquid crystal display device that can accurately and quickly determine whether the LCD panel is defective.

In order to achieve the above object, the present invention comprises the steps of manufacturing a single LCD panel by cutting a large glass substrate; Loading the LCD panel into an LCD inspection apparatus having an imaging device such as a camera to inspect whether the LCD panel is defective; Removing the shorting bar formed on the LCD panel using a polishing machine; Cleaning the LCD panel from which the shorting bar is removed; In addition, an inspection process of the liquid crystal display device including the step of directly inspecting the cleaned LCD panel by an operator to determine whether or not the final failure.

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

1 is a flowchart illustrating an inspection process of a liquid crystal display according to a first embodiment of the present invention.

First, a large glass substrate formed by joining an array substrate and a color filter substrate is cut to manufacture a single LCD panel.

Thereafter, the LCD panel is loaded into the LCD inspection apparatus to check whether the LCD panel is defective.

Here, the LCD inspection equipment comprises an imaging device such as a camera, unlike the LCD inspection equipment according to the prior art.

Figure 2 is a side cross-sectional view showing a schematic structure of the LCD inspection equipment according to the present invention.

As shown in FIG. 2, the LCD inspection apparatus includes a work table 110, a probe unit 120, a backlight unit 130, a polarizing plate 140, a moving stage 150, and imaging equipment. And made up of 160.

The work table 110 may have a rectangular box shape having an inner side thereof opened, and an LCD panel 10 may be seated on a front surface thereof.

The probe unit 120 is installed around the front opening side of the work table 110 and electrically connected to the shorting bar of the LCD panel 10 seated on the work table 110.

The shorting bar is formed for the inspection of the LCD panel 10. The shorting bar 200 (see FIG. 3) for applying an electrical signal to a plurality of gate lines and an electrical signal to a plurality of data lines. Data shorting bar 300 (see FIG. 4).

Therefore, various pattern-specific image signals for inspecting the LCD panel 10 provided to the probe unit 120 are provided to the LCD panel 10 through the shorting bar.

The backlight unit 130 may be provided at an inner rear side of the work table 110 to provide a light source to the LCD panel 10 seated on the front surface of the work table 110.

In addition, the polarizing plate 140 is installed at the inner front side of the work table 110 so that the light source emitted from the backlight unit 130 is irradiated to the LCD panel 10 in a polarized state.

In addition, the moving stage 150 is provided at the rear side of the work table 110, and serves to align and connect the work table 110 to the probe unit 120.

The imaging device 160 captures an image of each pattern displayed on the LCD panel 10 seated on the front of the work table 110. In this case, the image for each pattern photographed by the imaging device 160 is transmitted to a controller (not shown) made of a microcomputer, etc., and the controller extracts the defective information from the transmitted image.

Here, the defect information includes a point defect that is a defect for a pixel and a line defect that is a defect for a line as information on a substantial defect of the LCD panel 10.

The imaging device 160 is preferably composed of a CCD camera, the resolution is configured to have a resolution approximately equal to or higher than the resolution of the LCD panel 10.

As such, the LCD inspection apparatus photographs an image for each pattern displayed on the LCD panel 10 by using an imaging device 160 such as a CCD camera, and analyzes the photographed image in the controller to determine the LCD panel 10. Determination of defects can greatly improve the work efficiency and accuracy by supplementing the limitations of the inspection by the human eye.

On the other hand, when the above-described LCD panel 10 inspection step using the LCD inspection equipment is completed, a laser trimming step of removing the shorting bar formed on the LCD panel 10 by using a laser trimmer (S103). )

The shorting bar is formed for the inspection of the LCD panel 10 as described above and is removed by the laser trimmer after the inspection of the LCD panel 10 is completed.

When the laser trimming step is completed, a grinding step of precisely removing the remaining shorting bars that are not removed by the laser trimmer again using a polishing machine is performed (S104).

At this time, in the grinding step, as well as removing the shorting bar using the polishing machine, the operation of precisely trimming the cut surface of the LCD panel 10 cut and sharpened by the laser trimmer is performed at the same time.

As such, the shorting bar of the LCD panel 10 is completely removed through the laser trimmer and the polishing machine. In particular, the polishing machine also serves to precisely trim the cut surface by the laser trimmer.

However, since the laser trimming step requires expensive equipment, such as a separate laser trimmer, the additional cost is consumed, and there is a problem of lowering productivity because it is an additional process.

Therefore, the present invention proposes an LCD panel structure which can omit the laser trimming step.

3 is a plan view of a gate pad portion of an LCD panel according to the present invention, and FIG. 4 is a plan view of a data pad portion of an LCD panel according to the present invention.

First, as shown in FIG. 3, the LCD panel according to the present invention includes a gate pad 171 formed at an end of a gate wiring (not shown) and a gate terminal line 181 formed outside the gate pad 171. ).

In this case, the gate terminal line 181 and the gate pad are electrically connected through the connection pattern 190.

In detail, the connection pattern 190 is connected to the gate pad 171 through the second contact hole 192 and is connected to the gate terminal line 181 through the first contact hole 191 to the gate terminal line. 181 and the gate pad 171 are electrically connected to each other.

Meanwhile, a gate shorting bar 200 is formed at an outer portion of the gate terminal line 181 to be connected to the connection pattern 190 through a third contact hole 193 and electrically connected to the gate pad 171. .

The gate shorting bar 200 generally includes a first gate shorting bar 201 connected to an odd-numbered gate pad 171 and a second gate shorting bar 202 connected to an even-numbered gate pad 171. The presence or absence of a short circuit of the wiring is detected by the voltage difference flowing through the first and second gate shorting bars 201 and 202 through the gate wiring.

In this case, the gate terminal line 181 and the gate shorting bar 200 may be formed on the same layer as the gate pad 171. In this case, the first, second, and third contact holes 191, 192, 193 is formed by removing an insulating layer interposed between the gate wiring layer and the connection pattern 190.

Here, when the gate wiring layer is formed of AlNd having a low specific resistance, an area occupied by the gate terminal line 181 may be minimized.

In addition, as shown in FIG. 4, the LCD panel according to the present invention includes a data pad 172 formed at an end of a data line (not shown) and a data terminal line 182 formed outside the data pad 172. ).

In this case, the data terminal line 182 and the data pad 172 are electrically connected through the connection pattern 190.

In detail, the connection pattern 190 is connected to the data pad 172 through the second contact hole 192 and to the data terminal line 182 through the first contact hole 191 to the data terminal line. 182 and the data pad 172 are electrically connected to each other.

Meanwhile, a data shorting bar 300 is formed at an outer portion of the data terminal line 182 to be connected to the connection pattern 190 through a third contact hole 193 and electrically connected to the data pad 172.

The data shorting bar 300 generally includes a first data shorting bar 301 connected to an odd data pad 172 and a second data shorting bar 302 connected to an even data pad 172. The presence or absence of a short circuit of the wiring is detected by the voltage difference flowing through the data wiring through the first and second data shorting bars 301 and 302.

Here, the data terminal line 182 and the data shorting bar 300 may be formed on the same layer as the data pad 172. In general, since the data wiring layer uses molybdenum (Mo) of 0.15 Ω / μm, its width is increased. This can only grow.

However, when the data terminal line 182 and the data shorting bar 300 are simultaneously formed with the gate wiring layer, an area occupied by the data terminal line 182 may be minimized. At this time, the gate wiring layer is formed of AlNd of 0.05? / Μm.

As such, when the data terminal line 182 and the data shorting bar 300 are simultaneously formed with the gate wiring layer, the data shorting bar 300 may be formed to have a width of 50 to 60 μm, and the six data terminal lines 182 may be formed. May be formed to a width of 170 μm.

As a result, when the widths of the gate terminal line 181 and the data terminal line 182 are minimized as described above, the gate terminal line 181 and the data terminal line 182 are electrically connected to each other through the connection pattern 190. The width of the gate shorting bar 200 and the data shorting bar 300 is also minimized.

As such, when the width of the shorting bar is minimized, the shorting bar can be completely removed only by the grinding step without having to go through the laser trimming step.

That is, in the related art, the shorting bar is formed in a large width, and the removal of the shorting bar completely using only a polishing machine takes too much work time and is almost impossible due to static electricity. It is possible to remove the shorting bar completely using a grinder without going through the cutting process.

On the other hand, when the grinding step is completed, the LCD panel 10 is sent to the cleaning step (S105), the cleaning step is performed to remove the various foreign matter attached to the LCD panel 10 through the grinding step.

In addition, the cleaned LCD panel 10 is sent to the visual inspection step in which the operator directly inspects whether the LCD panel 10 is defective.

The visual inspection targets only the LCD panel 10 which is determined to be defective in the inspection using the above-described LCD inspection equipment, and the operator directly inspects the LCD panel which is determined to be defective by eyes to determine whether the final defect is present.

5 is a flowchart illustrating an inspection process of a liquid crystal display according to a second exemplary embodiment of the present invention.

On the other hand, as shown in Figure 5, the inspection process of the liquid crystal display according to the second embodiment of the present invention cleaning step for removing the surface foreign matter before loading the LCD panel 10 cut into a sheet to the LCD inspection equipment (S202) may be further included.

It is very likely that various foreign matters are on the sheet of LCD panels formed by cutting the large glass substrate. Therefore, if the foreign matter on the LCD panel is removed in advance through the cleaning process, the inspection of the LCD panel can be made more accurately.

In addition, the inspection process of the liquid crystal display according to the second embodiment of the present invention may further comprise the step of putting the LCD panel in the stocker before the cleaning step (S202) or the LCD panel inspection step (S102). )

The stocker is kept in a very clean state as a place where the LCD panel to be conveyed or transported through each process is temporarily stored. Therefore, it is desirable to keep the LCD panel as clean as possible by putting the LCD panel into the stocker when the LCD panel which has been cut after cutting is not immediately loaded into the LCD inspection equipment or sent to the cleaning step to remove foreign substances. .

Of course, the step of storing the above-described LCD panel in the stocker may be performed before the above-described visual inspection step (S203).

That is, even when the visual inspection step of checking for final defects is not performed immediately after the cleaning of the LCD panel from which the shorting bar is removed, it is desirable to keep the LCD panel as clean as possible by wearing the LCD panel in a stocker.

As such, if the LCD panel is stored in the stocker and kept as clean as possible, accurate inspection results can be obtained in the inspection step and the visual inspection step using the LCD inspection equipment.

As described above, the inspection process of the liquid crystal display according to the present invention has the following effects.

First, the image of each pattern displayed on the LCD panel is photographed using an imaging device such as a CCD camera, and the control unit analyzes the captured image to determine whether the LCD panel is defective. Complementary work can greatly improve work efficiency and accuracy.

Secondly, laser trimmers are not needed to remove the shorting bar, thus preventing additional expenses for purchasing expensive equipment and improving productivity by shortening the process.

Third, it is possible to accurately determine whether the LCD panel is defective by adding a pre-cleaning step before the LCD panel is loaded into the LCD inspection equipment or by putting the LCD panel in a stocker so as to prevent contamination.

Claims (6)

Cutting a large glass substrate to produce a single LCD panel; The LCD panel is loaded into an LCD inspection apparatus equipped with an imaging device such as a camera, and various image signals are provided to the LCD panel, and images of each pattern displayed on the LCD panel are taken. Analyzing the image for each pattern to check whether the LCD panel is defective; Removing the shorting bar formed on the LCD panel using a polishing machine; Cleaning the LCD panel from which the shorting bar is removed; And, An operator inspects the cleaned LCD panel directly with eyes to determine whether there is a final failure; And the shorting bar includes a gate shorting bar and a data shorting bar, wherein the gate shorting bar and the data shorting bar are simultaneously formed with the gate wiring layer. delete The method of claim 1, The step of checking whether or not the final failure of the LCD panel, the inspection process of the liquid crystal display device, characterized in that only for the LCD panel is determined to be defective in the inspection using the LCD inspection equipment. The method of claim 1, And inspecting the LCD panel in a stocker before storing the LCD panel for final defects. The method of claim 1, And cleaning the sheet of LCD panel to remove foreign substances from the surface of the LCD panel. The method of claim 1, And storing and storing the LCD panel in a stocker before loading the LCD panel into the LCD inspection apparatus.

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