JP4443779B2 - Liquid crystal display panel lighting display inspection method and inspection system - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a liquid crystal display panel lighting display inspection method and an inspection system using a liquid crystal display panel lighting display inspection device.
[0002]
[Prior art]
A thin film transistor (TFT) substrate that constitutes a liquid crystal display (LCD) is present in a TFT substrate defect inspection process using a TFT substrate defect inspection apparatus performed after the TFT substrate manufacturing process is completed. Has been inspected. In the TFT substrate defect inspection step, all the defects in the TFT substrate are detected by accumulating charges in the TFT / LCD cell capacitor and reading the charges accumulated by the integrator after holding for a certain time. Thereafter, the TFT substrate is judged good or bad by the number and position of defects.
[0003]
After the TFT substrate and the color filter (CF) substrate are bonded together and liquid crystal is injected, a liquid crystal display panel lighting display inspection is performed. FIG. 11 is a schematic configuration diagram showing a conventional liquid crystal display panel lighting display inspection process. First, the probe pins 106 of the probe 104 are brought into contact with all terminals of the liquid crystal display panel 102 to be inspected. Next, the processing system B 116 supplies a predetermined display signal to the terminal of the liquid crystal display panel 102 via the signal generator 114, the control board 112, the probe 104, and the probe pin 106. With this display signal, all inspection display patterns necessary for detecting all defects of the liquid crystal display panel 102 are displayed on the liquid crystal display panel 102. Further, the liquid crystal display panel 102 is illuminated by a backlight 108 from the back surface. Next, an image of the inspection display pattern of the liquid crystal display panel 102 obtained by the charge coupled device (CCD) camera 110 is analyzed by the processing system B116 to detect all display defects of the liquid crystal display panel 102. The quality of the liquid crystal display panel 102 is determined. Further, in the liquid crystal display panel lighting display inspection step, the presence or absence of unevenness and foreign matter is also inspected.
[0004]
The inspection result of the liquid crystal display panel 102 including the detected defect information is sent from the processing system B116 to the processing system A118. The processing system A 118 writes the inspection result of the liquid crystal display panel 102 in the liquid crystal display panel lighting display inspection apparatus database (DB) 120. TFT substrate defect inspection and liquid crystal display panel lighting display inspection are handled independently, and the inspection results in the liquid crystal display panel lighting display inspection process are stored in a separate database from the inspection results in the TFT substrate defect inspection process. The
[0005]
FIG. 12 is a schematic configuration diagram showing another conventional liquid crystal display panel lighting display inspection process. In the liquid crystal display panel lighting display inspection process shown in FIG. 12, the operator 122 looks at the inspection display pattern displayed on the liquid crystal display panel 102 without using the CCD camera 110 as shown in FIG. A defect is detected and the quality of the liquid crystal display panel 102 is determined. The inspection result of the liquid crystal display panel 102 is input to the processing system A 118 by the operator 122. The processing system A 118 writes the inspection result of the liquid crystal display panel 102 in the DB 120 for liquid crystal display panel lighting display inspection device.
[0006]
[Problems to be solved by the invention]
In the conventional liquid crystal display panel lighting display inspection process, all inspection display patterns necessary for detecting all display defects of the liquid crystal display panel 102 are displayed on the liquid crystal display panel 102. Therefore, there is a problem that a long time is required for the liquid crystal display panel lighting display inspection.
[0007]
The objective of this invention is providing the liquid crystal display panel lighting display test | inspection method and test | inspection system which shortened the test | inspection time of the liquid crystal display panel lighting display test | inspection.
[0008]
[Means for Solving the Problems]
The above object is a liquid crystal display panel lighting display inspection method for displaying a predetermined inspection display pattern on a liquid crystal display panel to be inspected and detecting a display defect of the liquid crystal display panel. The defect information of the detected defect type is obtained from the TFT substrate defect information database and the inspection for detecting the defect type is omitted.
[0009]
Another object of the present invention is to provide a liquid crystal display panel lighting display inspection system for displaying a predetermined inspection display pattern on a liquid crystal display panel to be inspected and detecting a display defect of the liquid crystal display panel. This is achieved by a liquid crystal display panel lighting display inspection system characterized in that the defect information of the defect type detected in the inspection process is acquired from the TFT substrate defect information database and the inspection for detecting the defect type is omitted.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
A liquid crystal display panel lighting display inspection method and inspection system according to an embodiment of the present invention will be described with reference to FIGS. First, a schematic configuration of a liquid crystal display panel lighting display inspection method and inspection system according to the present embodiment will be described with reference to FIG. FIG. 1 is a schematic configuration diagram showing a liquid crystal display panel lighting display inspection method and inspection system according to the present embodiment. The liquid crystal display panel 2 to be inspected is positioned on the backlight 8 so that the probe pins 6 of the probe 4 can come into contact with all terminals of the liquid crystal display panel 2. . Above the liquid crystal display panel 2, a CCD camera 10 for photographing the display state of the liquid crystal display panel 2 is disposed, and the CCD camera 10 sends the photographed image information to the processing system B16. The processing system B16 supplies a predetermined display signal to each terminal of the liquid crystal display panel 2 through the signal generator 14, the control board 12, the probe 4, and the probe pin 6, and analyzes image information sent from the CCD camera 10. It is supposed to be.
[0011]
The processing system B16 is connected to the processing system A18. The processing system A18 is connected via a local area network (LAN) 28 to a DB 20 for liquid crystal display panel lighting display inspection apparatus that stores the inspection results of the liquid crystal display panel lighting display inspection. On the LAN 28, a TFT substrate defect inspection apparatus 26 used for the TFT substrate defect inspection process in the previous process and a TFT substrate defect information DB 24 storing inspection results of the TFT substrate defect inspection are further connected.
[0012]
Next, a liquid crystal display panel lighting display inspection method according to the present embodiment will be described. First, the TFT substrate and the CF substrate that have passed the TFT substrate defect inspection are bonded together, and a liquid crystal display panel 2 formed by injecting liquid crystal between the two substrates is placed on the backlight 8 using a transport device (not shown). Then, the probe pins 6 are brought into contact with all terminals of the liquid crystal display panel 2. Next, the processing system B16 supplies a display signal that causes the liquid crystal display panel 2 to display a predetermined inspection display pattern to all the terminals of the liquid crystal display panel 2. The CCD camera 10 disposed above the liquid crystal display panel 2 captures an inspection display pattern displayed on the liquid crystal display panel 2. The CCD camera 10 sends the captured image information to the processing system B16. The processing system B16 analyzes the image information to detect display defects, and sends the display defect detection result of the liquid crystal display panel 2 to the processing system A18 connected to the LAN.
[0013]
Here, the display defects detected in the liquid crystal display panel lighting display inspection step include defect types detected in the TFT substrate defect inspection step, which is a previous step. Next, four defect types that can be detected in the TFT substrate defect inspection process and that can be detected in the liquid crystal display panel lighting display inspection process will be described with reference to FIGS.
[0014]
FIG. 2 is a plan view of the pixel region showing the first defect type. On the insulating glass substrate 32, a pixel region is defined by a gate bus line 36 extending in the left-right direction in the drawing and a drain bus line 38 extending in the vertical direction in the drawing. A pixel electrode 34 is formed in the pixel region. A storage capacitor bus line 40 is formed across the pixel region at substantially the center of the pixel region. An intermediate electrode 51 is formed on the storage capacitor bus line 40, and the intermediate electrode 51 and the pixel electrode 34 are connected through a contact hole 52. In the upper left of the pixel region in the figure, there are a gate bus line 36, a drain electrode 42 extending from the drain bus line 38, and a source electrode 44 formed facing the drain electrode 42 with a predetermined gap. A TFT 45 is formed. A region surrounded by an ellipse below the TFT 45 in the drawing indicates a first defect type. This defect type is formed when the drain bus line 38 and the intermediate electrode 51 are connected, and the drain bus line 38 and the pixel electrode 34 are short-circuited via the intermediate electrode 51 and the contact hole 52. ing.
[0015]
FIG. 3 shows a black-and-white upper and lower divided inspection display pattern which is one of the inspection display patterns displayed in the liquid crystal display panel lighting display inspection process. As shown in FIG. 3, the display area 46 is divided into two upper and lower areas. The upper part is displayed in white (or black), and the lower part is displayed in black (or white). In the lower left part of the display area 46, a halftone bright spot defect 50 is generated in the area displaying black. In this display, black and white are reversed at intervals of about the time required for photographing by the CCD camera 10 (for example, several seconds).
[0016]
In the defect type shown in FIG. 2, since the pixel electrode 34 and the drain bus line 38 are short-circuited, the voltage change of the gradation voltage on the drain bus line 38 becomes the voltage change of the pixel electrode 34 as it is. When the black and white vertically divided inspection display pattern shown in FIG. 3 is displayed, for example, the gradation voltage of the drain bus line 38 in the normally black mode liquid crystal display panel driven by frame inversion is, for example, the first half of the frame for each frame. ± 5V and the latter half becomes ± 1V, for example. If one frame period is 1/60 sec (seconds), the pixel having the defect type shown in FIG. 2 is visually recognized as a halftone point because white display and black display are repeated every 1/120 sec. Therefore, a pixel having the defect type shown in FIG. 2 becomes a dark spot defect if it is in the white display area, and a bright spot defect if it is in the black display area. This is the same in the dot inversion driving and the same in the normally white mode.
[0017]
FIG. 4 is a plan view of the pixel region showing the second defect type. A region surrounded by a circle on the TFT 45 indicates a state where the drain electrode 42 and the source electrode 44 are short-circuited. In the pixel having the defect type shown in FIG. 4, the voltage change of the gradation voltage of the drain bus line 38 becomes the voltage change of the pixel electrode 34 as it is, like the pixel having the defect type shown in FIG. Therefore, by displaying the black and white vertically divided inspection display pattern shown in FIG. 3, a dark spot defect occurs in the white display area and a bright spot defect exists in the black display area.
[0018]
FIG. 5 is a plan view of a pixel region showing a third defect type. A region surrounded by an ellipse on the lower left side of the TFT 45 in the figure is formed with the drain bus line 38 connected to the intermediate electrode 51 on the left side in the figure, and the drain bus line 38 and the pixel electrode 34 on the left side in the figure are connected. A state in which the intermediate electrode 51 and the contact hole 52 are short-circuited is shown. In the pixel having the defect type shown in FIG. 5, the voltage change of the gradation voltage of the drain bus line 38 becomes the voltage change of the pixel electrode 34 on the left side in the drawing. Therefore, by displaying the black and white vertically divided inspection display pattern shown in FIG. 3, a dark spot defect occurs in the white display area and a bright spot defect exists in the black display area.
[0019]
FIG. 6 is a plan view of the pixel region showing the fourth defect type. A region surrounded by a circle on the right side of the TFT 45 in the drawing shows a state in which the pixel electrode 34 is short-circuited with the pixel electrode 34 in the upper pixel region in the drawing.
[0020]
FIG. 7 shows a horizontal stripe pattern inspection display pattern which is one of the inspection display patterns displayed in the liquid crystal display panel lighting display inspection process. As shown in FIG. 7, in the display area 46, lines having a thickness of one pixel in the horizontal direction in the figure are alternately displayed in black and white every other line. In the upper left part of the figure, there is a bright spot defect 48 in which a line displaying black is partially interrupted. FIG. 8 shows an enlarged view of the vicinity of the bright spot defect 48 in the display area 46 shown in FIG. Of the lines displaying black displayed in the display area 46, the second line from the top in the figure is interrupted by one pixel. The pixels having the defect type shown in FIG. 6 display in the display area 46 a horizontal stripe pattern inspection display pattern in which the lines in the direction of the gate bus line 36 are alternately displayed in black and white every other line in the liquid crystal display panel lighting display inspection step. Is detected. This inspection display pattern is inverted and displayed at intervals of about the time required for photographing by the CCD camera 10 (for example, several seconds).
[0021]
In the defect type shown in FIG. 6, the pixel electrode 34 formed in the upper and lower adjacent pixel regions is short-circuited, so that the pixel potential of the upper pixel becomes the same as the pixel potential of the lower pixel. That is, when the lower pixel in the figure is on a line displaying white, the upper pixel in the figure displays white even though it is on a line displaying black. As shown in FIG. Conversely, when the lower pixel in the figure is on the line displaying black, the upper pixel in the figure displays black even though it is on the line displaying white, and this is a dark spot defect. Become. These are the same in both the normally black mode and the normally white mode, and are the same in both the frame inversion driving and the dot inversion driving.
[0022]
The above four defect types have already been detected in the TFT substrate defect inspection process, which is a previous process. In addition, these defect types are detected only when the black and white upper and lower divided inspection display pattern or the horizontal stripe inspection display pattern is displayed in the liquid crystal display panel lighting display inspection process. Therefore, in the liquid crystal display panel lighting display inspection process, defect information of these defect types detected in the TFT substrate defect inspection process is acquired from the TFT substrate defect information DB 24, thereby performing inspection for detecting these defect types. Can be omitted.
[0023]
Returning to FIG. 1, the inspection result of the TFT substrate defect inspection is written in the TFT substrate defect information DB 24. The defect information included in the inspection result includes, for example, data such as an inspection date, a lot number, a serial number, a gate bus line number and a drain bus line number for specifying a defective pixel, and a defect type. . The processing system A18 retrieves and acquires defect information on the above-described first to fourth defect types from the TFT substrate defect information DB 24 via the LAN 28, and sends the defect information to the processing system B16. The processing system B16 judges these defect types as defects detected in the liquid crystal display panel lighting display inspection, omits the inspection by not displaying the inspection display pattern for detecting those defect types, and sends the sent defect information. And the liquid crystal display panel lighting display inspection result are combined to determine whether the liquid crystal display panel 2 is good or bad. Next, the processing system B16 sends the final liquid crystal display panel lighting display inspection result including the TFT substrate defect information to the processing system A. The processing system A writes the final liquid crystal display panel lighting display inspection result in the liquid crystal display panel lighting display inspection apparatus DB 20.
[0024]
According to the liquid crystal display panel lighting display inspection method and inspection system according to the present embodiment, the inspection for detecting the defect type detected in the TFT substrate defect inspection process is omitted in the liquid crystal display panel lighting display inspection process. Can do. Therefore, the inspection time of the liquid crystal display panel lighting display inspection can be shortened by reducing the displayed inspection display patterns. When the liquid crystal display panel lighting display inspection method and inspection system according to the present embodiment is applied to a certain liquid crystal display panel lighting display inspection process, the lighting display inspection time per liquid crystal display panel conventionally takes 150 seconds. It was 90 seconds, which was 40% shorter. Also, the outflow of defective panels to the subsequent process could be reduced more than ever.
[0025]
FIG. 9 is a schematic configuration diagram showing a modification of the liquid crystal display panel lighting display inspection method and inspection system according to the above embodiment. This modification is characterized in that the defect information acquired by the processing system A18 by searching from the TFT substrate defect information DB 24 is not sent to the processing system B16. For this reason, the processing system B16 does not make a pass / fail determination based on the final liquid crystal display panel lighting display inspection result, and sends only the inspection result in the liquid crystal display panel lighting display inspection process to the processing system A18. The processing system A18 determines the quality of the liquid crystal display panel 2 by combining the liquid crystal display panel lighting display inspection result and defect information sent from the processing system B16. The effect similar to the said embodiment is acquired also by this modification.
[0026]
FIG. 10 is a schematic configuration diagram showing another modification of the liquid crystal display panel lighting display inspection method and inspection system according to the above embodiment. In this modified example, the image obtained by the CCD camera 10 is not analyzed by the processing system B16, but the operator 22 visually observes the inspection display pattern displayed on the liquid crystal display panel 2 to detect defects in the liquid crystal display panel 2. It is characterized by detecting. The inspection result of the liquid crystal display panel 2 is input by the operator 22 to the processing system A18. The processing system A18 determines the quality of the liquid crystal display panel 2 by combining the input inspection result of the liquid crystal display panel 2 and the defect information retrieved from the TFT substrate defect information DB 24. The effect similar to the said Example is acquired also by this modification.
[0027]
The present invention is not limited to the above embodiment, and various modifications can be made.
For example, in the liquid crystal display panel lighting display inspection method and inspection system according to the above embodiment shown in FIG. 1, the image information sent from the CCD camera 10 is analyzed by the processing system B16. Not limited to. If the load on the processing system B16 is large, a processing system for image processing analysis may be provided separately from the processing system B16. In this case, the processing speed is reduced because it is via the dedicated interface, but the image processing analysis with a very large load is performed in another processing system, so that the load on the processing system B16 can be reduced.
[0028]
The liquid crystal display panel lighting display method and display system according to the embodiment described above can be summarized as follows.
(Appendix 1)
A liquid crystal display panel lighting display inspection method for displaying a predetermined inspection display pattern on a liquid crystal display panel to be inspected and detecting a display defect of the liquid crystal display panel,
Obtain defect information of defect types detected in the TFT substrate defect inspection process of the previous process from the TFT substrate defect information database,
A liquid crystal display panel lighting display inspection method, wherein the inspection for detecting the defect type is omitted.
[0029]
(Appendix 2)
In the liquid crystal display panel lighting display inspection method according to attachment 1,
The liquid crystal display panel lighting display inspection method characterized in that the omitted inspection includes displaying an inspection display pattern on the liquid crystal display panel and detecting a display defect.
[0030]
(Appendix 3)
In the liquid crystal display panel lighting display inspection method according to appendix 1 or 2,
The defect type indicates that a pixel electrode formed on the TFT substrate and a drain bus line for applying a gradation voltage to the pixel electrode are short-circuited. Inspection method.
[0031]
(Appendix 4)
In the liquid crystal display panel lighting display inspection method according to appendix 1 or 2,
The liquid crystal display panel lighting display inspection method, wherein the defect type indicates that a drain electrode and a source electrode of a TFT formed on the TFT substrate are short-circuited.
[0032]
(Appendix 5)
In the liquid crystal display panel lighting display inspection method according to appendix 1 or 2,
The defect type is a short circuit between a pixel electrode formed in a pixel region on the TFT substrate and a drain bus line for applying a gradation voltage to a pixel electrode formed in a pixel region adjacent to the pixel region. A liquid crystal display panel lighting display inspection method characterized by showing.
[0033]
(Appendix 6)
In the liquid crystal display panel lighting display inspection method according to appendix 1 or 2,
The defect type is a short circuit between the pixel electrode formed in the pixel region on the TFT substrate and the pixel electrode formed in the adjacent pixel region in the extending direction of the drain bus line for applying a gradation voltage to the pixel electrode. A liquid crystal display panel lighting display inspection method characterized by showing that
[0034]
(Appendix 7)
A liquid crystal display panel lighting display inspection system for displaying a predetermined inspection display pattern on a liquid crystal display panel to be inspected and detecting a display defect of the liquid crystal display panel,
Obtain defect information of defect types detected in the TFT substrate defect inspection process of the previous process from the TFT substrate defect information database,
A liquid crystal display panel lighting display inspection system, wherein inspection for detecting the defect type is omitted.
[0035]
(Appendix 8)
In the liquid crystal display panel lighting display inspection system according to appendix 7,
The liquid crystal display panel lighting display inspection system is characterized in that the inspection to be omitted includes displaying an inspection display pattern on the liquid crystal display panel to detect a display defect.
[0036]
(Appendix 9)
In the liquid crystal display panel lighting display inspection system according to appendix 7 or 8,
The defect type indicates that a pixel electrode formed on the TFT substrate and a drain bus line for applying a gradation voltage to the pixel electrode are short-circuited. Inspection system.
[0037]
(Appendix 10)
In the liquid crystal display panel lighting display inspection system according to appendix 7 or 8,
The defect type indicates that the drain electrode and the source electrode of the TFT formed on the TFT substrate are short-circuited, wherein the liquid crystal display panel lighting display inspection system is characterized.
[0038]
(Appendix 11)
In the liquid crystal display panel lighting display inspection system according to appendix 7 or 8,
In the defect type, the pixel electrode formed in the pixel region on the TFT substrate and the drain bus line for applying the gradation voltage to the pixel electrode formed in the pixel region adjacent to the pixel region are short-circuited. A liquid crystal display panel lighting display inspection system characterized by showing.
[0039]
(Appendix 12)
In the liquid crystal display panel lighting display inspection system according to appendix 7 or 8,
The defect type is a short circuit between the pixel electrode formed in the pixel region on the TFT substrate and the pixel electrode formed in the adjacent pixel region in the extending direction of the drain bus line for applying a gradation voltage to the pixel electrode. A liquid crystal display panel lighting display inspection system characterized by showing that
[0040]
【The invention's effect】
As described above, according to the present invention, the inspection time of the liquid crystal display panel lighting display inspection can be shortened.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram showing a liquid crystal display panel lighting display inspection method and inspection system according to an embodiment of the present invention.
FIG. 2 is a plan view of a pixel region showing a first defect type to which a liquid crystal display panel lighting display inspection method and inspection system according to an embodiment of the present invention is applied.
FIG. 3 is a diagram showing a black and white upper and lower divided inspection display pattern displayed in a liquid crystal display panel lighting inspection process;
FIG. 4 is a plan view of a pixel region showing a second defect type to which a liquid crystal display panel lighting display inspection method and inspection system according to an embodiment of the present invention is applied.
FIG. 5 is a plan view of a pixel region showing a third defect type to which a liquid crystal display panel lighting display inspection method and inspection system according to an embodiment of the present invention is applied.
FIG. 6 is a plan view of a pixel region showing a fourth defect type to which a liquid crystal display panel lighting display inspection method and inspection system according to an embodiment of the present invention is applied.
FIG. 7 is a diagram showing a horizontal stripe pattern inspection display pattern displayed in a liquid crystal display panel lighting inspection step.
FIG. 8 is an enlarged view showing a horizontal stripe pattern inspection display pattern displayed in a liquid crystal display panel lighting inspection step.
FIG. 9 is a schematic configuration diagram showing a modification of the liquid crystal display panel lighting display inspection method and inspection system according to the embodiment of the present invention.
FIG. 10 is a schematic configuration diagram showing another modification of the liquid crystal display panel lighting display inspection method and inspection system according to the embodiment of the present invention.
FIG. 11 is a configuration diagram showing a conventional liquid crystal display panel lighting display inspection process.
FIG. 12 is a configuration diagram showing another conventional liquid crystal display panel lighting display inspection process.
[Explanation of symbols]
2 Liquid crystal display panel 4 Probe 6 Probe pin 8 Backlight 10 CCD camera 12 Control board 14 Signal generator 16 Processing system B
18 Processing system A
20 Liquid crystal display panel lighting display inspection DB
22 Operator 24 TFT substrate defect information DB
26 TFT substrate defect inspection device 28 LAN
32 glass substrate 34 pixel electrode 36 gate bus line 38 drain bus line 40 storage capacitor bus line 42 drain electrode 44 source electrode 45 TFT
46 Display area 48, 50 Bright spot defect 51 Intermediate electrode 52 Contact hole

Claims (5)

A liquid crystal display panel lighting display inspection method for displaying a predetermined inspection display pattern on a liquid crystal display panel to be inspected and detecting a display defect of the liquid crystal display panel,
Obtain defect information of a predetermined defect type detected in the TFT substrate defect inspection process of the previous process from the TFT substrate defect information database,
Omit the inspection to detect the defect type ,
A liquid crystal display panel lighting display inspection method comprising: determining the quality of the liquid crystal display panel by combining the acquired defect information of the predetermined defect type and the liquid crystal display panel lighting display inspection result . In the liquid crystal display panel lighting display inspection method according to claim 1,
The defect type indicates that a pixel electrode formed on the TFT substrate and a drain bus line for applying a gradation voltage to the pixel electrode are short-circuited. Inspection method. In the liquid crystal display panel lighting display inspection method according to claim 1,
The defect type indicates that the drain electrode and the source electrode of the TFT formed on the TFT substrate are short-circuited. In the liquid crystal display panel lighting display inspection method according to claim 1,
The defect type is a short circuit between a pixel electrode formed in a pixel region on the TFT substrate and a drain bus line for applying a gradation voltage to a pixel electrode formed in a pixel region adjacent to the pixel region. A liquid crystal display panel lighting display inspection method characterized by In the liquid crystal display panel lighting display inspection method according to claim 1,
The defect type is a short circuit between the pixel electrode formed in the pixel region on the TFT substrate and the pixel electrode formed in the adjacent pixel region in the extending direction of the drain bus line for applying a gradation voltage to the pixel electrode. A liquid crystal display panel lighting display inspection method characterized by showing that

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