JP2000155302A - Test method and test device for liquid crystal display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable displaying red, green, and blue and to improve test and detection capability for defect caused by patterns of each pixel constitution, wirings, and the like even when pixel electrodes are arranged in delta arrangement in a test method for a liquid crystal display device. SOLUTION: The device is provided with a first gate side test wiring G1 connected to gate wirings 2 to which a gate potential of each switching element 4 of odd rows in arrangement of pixels is respectively applied and a second gate side test wiring G2 connected to gate wirings 2 to which a gate potential of each switching element 4 of even rows is respectively applied, and the device performs display by a drive potential to the first gate side test wiring G1 and a drive potential to source side test wirings S1-S3 and display by a drive potential to the second gate side test wiring G2 and a drive potential to source side test wirings S1-S3. By this method, even if pixel electrodes of red, green, blue are arranged in delta arrangement, display of red, green, blue can be performed, a simple picture test can be realized, and a test having high detecting capability for defect can be performed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for testing an active matrix type liquid crystal display device.

[0002]

2. Description of the Related Art In recent years, a liquid crystal display device has attracted attention as a display device for displaying characters and information because of its size and low power consumption. Among them, an active matrix type liquid crystal display device in which a switching element typified by a TFT (thin film transistor) is connected to each pixel in order to provide a quick response and a clear display of a moving image has attracted attention.

Active matrix liquid crystal display devices include those in which pixel electrodes for displaying red, green, and blue are arranged in a delta arrangement and those in which they are arranged in a stripe arrangement.
FIG. 1 shows a configuration of a liquid crystal display device in which pixel electrodes are arranged in a delta arrangement.
3 and FIG. FIG. 13 is a plan view of a liquid crystal display device having a delta arrangement, and FIG. 14A is an AA ′ shown in FIG.
FIG. 14B is a cross-sectional view taken along the line.
It is sectional drawing which follows the B 'line.

The pixel electrode 1r for displaying red, the pixel electrode 1g for displaying green, and the pixel electrode 1b for displaying blue are arranged in a delta arrangement. That is, pixel electrodes 1 of three colors, red, green and blue, are periodically and repeatedly arranged in odd rows in the horizontal direction, and the same arrangement as the odd rows is shifted in the horizontal direction by 1.5 pixels in even rows. It is arranged.

[0005] A gate line 2 and a source line 3 are arranged between these pixel electrodes 1. As described above, in the delta arrangement, the pixel electrodes 1 of the same color
Are arranged in the same column for each wiring. A switching element 4 typified by the TFT is disposed at the intersection of the gate line 2 and the source line 3, and the red pixel electrode 1 r, the green pixel electrode 1 g, and the blue pixel The electrode 1b and the source wiring 3 are electrically connected or disconnected. In addition, the pixel electrode 1 has a storage capacitor 9 for holding the potentials of the pixel electrode 1 and the counter electrode 8, which is adjacent to the gate line 2 (which is adjacent to the gate line 2 that applies a potential to the gate of the switching element 4). Gate wiring).

In this delta arrangement, two source pixel electrodes 1 of two colors different for each row, that is, a pixel electrode 1 of a pixel in the same column for each odd line and an even number are connected to one source line 3 via a switching element 4. The pixel electrode 1 of a pixel which is shifted in the horizontal direction by 0.5 pixel from the column of the odd-numbered row in the same column for each row is connected. For example, the red pixel electrode 1r and the green pixel electrode 1g are connected. A green pixel electrode 1g and a blue pixel electrode 1b,
The same applies to the blue pixel electrode 1b and the red pixel electrode 1r.

In FIG. 13, reference numeral 5 denotes a gate drive circuit for applying a drive potential to the gate wiring 2, reference numeral 6 denotes a source drive circuit for applying a drive potential to the source wiring 3, and reference numeral 7 denotes a counter electrode for applying a drive potential to the counter electrode 8. A gate drive circuit 5, a source drive circuit 6, and a counter electrode drive circuit 7
Are located outside the screen.

[0008] As shown in FIG.
Characters and information are displayed by opposing the opposing electrode 8 with 0 interposed therebetween and changing the ratio of transmitted light by the potential difference between the pixel electrode 1 and the opposing electrode 8.

FIG. 15 shows a configuration of a liquid crystal display device in which pixel electrodes are arranged in a stripe arrangement and a configuration of inspection wiring. FIG. 15 shows the state of inspection before completion. FIG.
As shown in FIG. 5, in a horizontal row, a pixel electrode 1r for displaying red, a pixel electrode 1g for displaying green, and a pixel electrode 1b for displaying blue are periodically and repeatedly arranged. Have pixel electrodes 1 of the same color.

In the conventional method of inspecting a liquid crystal display device, in order to produce the liquid crystal display device with a high yield, the gate drive circuit 5, the source drive circuit 6, and the counter electrode drive circuit 7
Is connected to all the gate lines 2, the source lines 3, and the counter electrode 8 to apply a potential to perform a defect detection inspection for displaying white, black, red, green, and blue screens.

In this defect detection inspection, a probe is mainly used to connect the inspection circuit to the gate wiring 2 and the source wiring 3. However, if the liquid crystal display device is small and high definition, it is difficult or difficult to manufacture the probe. Impossible.

In a liquid crystal display device in which the pixel electrodes 1 are arranged in a stripe arrangement, in order to eliminate these disadvantages,
As shown in FIG. 15, the gate-side inspection lines G connected to all the gate lines 2, the source-side inspection lines S1 connected to all of the source lines 3 corresponding to red, and all of the source lines 3 corresponding to green. Inspection wiring S2 connected to the source
, And a total of five inspection wirings including a source-side inspection wiring S3 connected to all of the source wirings 3 corresponding to blue and a counter electrode-side inspection wiring C connected to the counter electrode 8 are provided. A simple inspection configuration is adopted in which the inspection wiring is cut at a cutting portion T after the inspection wiring is connected and inspected.

[0013]

However, in such a conventional inspection method for a liquid crystal display device, the switching element 4 is not provided.
Must always be inspected in a conductive state, and a defect caused by the opening and closing of the switching element 4 and the switching element 4
However, there is a problem that a defect caused by the characteristic defect cannot be detected.

Further, in a liquid crystal display device in which the pixel electrodes 1 are arranged in a delta arrangement, two
Since the color pixel electrodes 1 are connected, there is a problem that red, green, and blue cannot be displayed in a single color, and the inspection detection power is reduced.

According to the present invention, in such a method of inspecting a liquid crystal display device, a defect can be inspected without using a probe, and even when pixel electrodes are arranged in a delta arrangement, display of red, green, and blue is performed. It is an object of the present invention to make it possible to improve the inspection detection power of a defect caused by a pattern of each pixel configuration and each wiring.

Further, even when the pixel electrodes are arranged in a stripe arrangement, a defect due to the switching element, a defect due to a characteristic defect of the switching element, a defect due to a variation in retention characteristics of the pixel potential,
Further, it is an object of the present invention to improve the inspection detection power of a defect caused by each pixel configuration and each wiring pattern.

[0017]

In the method of testing a liquid crystal display device according to the present invention, a storage capacitor for holding a pixel potential of a pixel electrode of each pixel applies a potential to a gate of a switching element of the pixel. An inspection method of an active matrix type liquid crystal display device connected to another gate line adjacent to a gate line, wherein a first gate connected to a gate line for applying a potential to a gate of a switching element of each pixel in an odd row Side inspection wiring and a second gate inspection wiring connected to a gate wiring for applying a potential to the gates of the switching elements in the even-numbered rows, and the second inspection wiring is applied to the first gate inspection wiring and the second gate inspection wiring. It is characterized in that odd-numbered rows of pixels and even-numbered rows of pixels are separately driven by a drive potential.

According to the present invention, defect inspection can be performed without using a probe, and even when pixel electrodes are arranged in a delta arrangement, red, green, and blue can be displayed. A method of inspecting a liquid crystal display device that improves the inspection detection power of a defect caused by the pattern of each wiring or the like can be obtained.

[0019]

DETAILED DESCRIPTION OF THE INVENTION According to the first aspect of the present invention, a storage capacitor for holding a pixel potential of a pixel electrode of each pixel includes a gate wiring for applying a potential to a gate of a switching element of the pixel. A method for testing an active matrix type liquid crystal display device connected to another gate line adjacent to a first gate side, the first gate side test being connected to a gate line for applying a potential to the gate of a switching element of each pixel in an odd row. A wiring, and a second gate-side inspection wiring connected to a gate wiring for applying a potential to the gates of the switching elements in the even-numbered rows, and a driving potential applied to the first gate-side inspection wiring and the second gate-side inspection wiring Thus, the pixels of the odd-numbered rows and the pixels of the even-numbered rows are separated and driven, and the additional configuration of the storage capacitor connects the storage capacitor to the adjacent gate line. In a liquid crystal display device, a red pixel electrode, a green pixel electrode, and a blue pixel electrode are arranged in a delta arrangement, and even if two color pixel electrodes are connected to one source line via a switching element, As in the case of the liquid crystal display devices arranged in a stripe arrangement, an effect is obtained that a simple image inspection can be realized.

According to a second aspect of the present invention, the storage capacitor for holding the pixel potential of the pixel electrode of each pixel includes another gate wiring adjacent to the gate wiring for applying a potential to the gate of the switching element of the pixel. A method for testing an active matrix type liquid crystal display device connected to
Three source-side inspection wires of each color connected to the source wires of the column in which pixels of green and blue are arranged, or the combination of the colors of the pixels of the odd-numbered rows and the colors of the pixels of the even-numbered rows in the column are the same A first gate-side inspection line connected to a gate line for applying a potential to a gate of a switching element of each pixel in an odd-numbered row; and the switching elements in an even-numbered row. A second gate-side inspection line connected to a gate line for applying a potential to the gate of the pixel, and a counter electrode-side inspection line connected to a counter electrode provided so that the pixel electrodes of the respective pixels are opposed to each other with a liquid crystal interposed therebetween. The switching element whose gate is connected to the first gate-side inspection wiring is turned on from the off-state for a predetermined period of time by the potential applied to the first gate-side inspection wiring, and then turned off. During a predetermined period, the second gate-side inspection line applies an operation via a storage capacitor to the pixel potential of the pixel electrode via a switching element connected to the first gate-side inspection line via a storage capacitor. The gate is turned on from the off state for a predetermined period of time from the off state by the potential applied to the second gate side inspection wiring, and then turned off,
During the predetermined period, the operation of applying the gate to the pixel potential of the pixel electrode via the switching element connected to the second gate-side inspection wiring via the storage capacitor is performed by the first gate-side inspection wiring. When the operation of turning off the switching elements by the potentials applied to the first gate-side inspection wiring and the second gate-side inspection wiring is set to operation 3, operation 1, operation 2, operation 3, operation 2, A series of operations is repeated in the order of operation 1 and operation 3, and a data signal is applied to each of the source side inspection wirings of red, green and blue according to the selected color, and white, black, red, green and It is characterized by performing inspection by displaying a blue color monochromatic screen, and in a liquid crystal display device in which a storage capacitor that holds the potential of a pixel electrode and a counter electrode is connected to an adjacent gate line, a red pixel Electric , A green pixel electrode and a blue pixel electrode are arranged in a delta arrangement, and even if two color pixel electrodes are connected to one source line via a switching element, a simple image is obtained by inspection before completion of the liquid crystal display device. Inspection is possible, and has the effect that the correlation of the visual recognition of the defect of the liquid crystal display device is higher than that of the driving screen when the liquid crystal driving circuit is formed, and the source and gate wirings are short-circuited with the respective inspection wirings. This has the effect of preventing the destruction of the switching element and defective switching characteristics due to static electricity.

The invention according to claim 3 is the invention according to claim 1 or 2, wherein the switching element is turned on by a potential applied to the first gate-side inspection wiring or the second gate-side inspection wiring. When a potential for turning off the switching element is Voff and a potential for turning on the switching element is Von during a predetermined period of the state, the potential of the gate wiring in the liquid crystal display device is changed from the Voff potential to the Von potential. ｛0.9 × (Von-Vof
f) a rising period of + Voff}, a period required to write a data signal from the source line to the pixel electrode via the switching element, and a Voff potential from the state where the potential of the gate line is Von. 0.9 ×
(Voff-Von) + Von}, which is equal to or longer than the sum of the falling period, and the rising period in which the potential of the gate wiring in the liquid crystal display device is Von from the state of Voff and Von potential is applied; A Voff potential is applied by applying a Voff potential from a period required for writing data from a source wiring to a pixel electrode via a switching element and a potential of a gate wiring in the liquid crystal display device being Von.
In the inspection before the completion of the liquid crystal display device, the defect of the liquid crystal display device is visually recognized as compared with the driving screen at the time of forming the liquid crystal driving circuit. Has the effect of increasing the correlation and consistency.

A fourth aspect of the present invention is the invention according to any one of the first to third aspects, wherein the period of the operation 1 and the period of the operation 2 are the same as the predetermined period when the switching element is turned on. This is characterized in that the period is twice or more, and the possibility that the potential at the time of switching of the drive potential of the source wiring is written to the pixel while the gate potential of the switching element is not completely turned off is avoided. The operation of writing the data signal from the pixel electrode to the pixel electrode is performed appropriately and reliably.

The invention according to claim 5 is the invention according to any one of claims 1 to 4, wherein each switching is performed by applying a potential to the first gate-side inspection wiring and the second gate-side inspection wiring. There are two types of long and short periods in which the element is in the off state, and the longer period is set equal to the period in which the pixel in the liquid crystal display device can hold the written potential. In the inspection before completion, it is possible to recognize a point defect due to the variation in the holding characteristic of the pixel potential, and it is possible to enhance the correlation and the consistency of the visual recognition failure of the liquid crystal display device as compared with the driving screen when the liquid crystal driving circuit is formed. Having.

The invention according to claim 6 is the invention according to any one of claims 1 to 5, wherein the two wirings and the inspection wirings are connected in accordance with the resistance and the capacitance of each of the inspection wirings. The driving potential applied from the gate-side inspection wiring and the three source-side inspection wirings to turn the switching element on and off, and the data signal written to the pixel electrode are temporally delayed or advanced. In the inspection before the completion of the liquid crystal display device,
When writing a data signal from a source line to a pixel electrode through a switching element, a margin is maintained for a gate threshold value of the switching element, and an operation of writing a data signal from a source line to the pixel electrode is appropriately and reliably performed. It has the effect that it can be performed.

According to a seventh aspect of the present invention, in the inspection apparatus for a liquid crystal display device, the storage capacitor for holding the pixel potential of the pixel electrode of each pixel includes a gate wiring for applying a potential to the gate of the switching element of the pixel. An inspection device for an active matrix type liquid crystal display device connected to another gate line adjacent to the device, comprising three lines for each color connected to a source line of a column in which pixels of red, green, and blue are arranged. Of the source-side inspection wiring or the combination of the color of the pixel of the odd-numbered row and the color of the pixel of the even-numbered row in the column connected to the same source wiring.
A source-side inspection line is provided, a first gate-side inspection line connected to a gate line for applying a potential to the gate of a switching element of each pixel in an odd-numbered row, and a potential is applied to a gate of the switching element in an even-numbered row. A second gate-side inspection line connected to the gate line; and a counter-electrode-side inspection line connected to a counter electrode provided so that all of the pixel electrodes of each of the pixels are opposed to each other with the liquid crystal interposed therebetween. A selection means for selecting a color is provided, and a drive potential corresponding to the color selected by the selection means is supplied to the three source-side inspection wirings, the first and second gate-side inspection wirings, and the counter electrode-side inspection wiring. Signal generating means for applying a signal, wherein a red pixel electrode, a green pixel electrode, and a blue pixel electrode are arranged in a delta arrangement, and one source arrangement is provided via the switching element. Even if two-color pixel electrodes are connected, simple image inspection can be realized in the same manner as in a liquid crystal display device in which the pixel electrodes are arranged in a stripe arrangement, and the arrangement of the pixel electrodes is a delta arrangement or a stripe arrangement. Irrespective of the above, there is an effect that the inspection can be performed with an increased correlation with the actual driving screen when the liquid crystal driving circuit is formed.

Hereinafter, a method for testing a liquid crystal display device and an apparatus thereof according to an embodiment of the present invention will be described with reference to the drawings. The same components as those of the conventional example shown in FIGS. 13 to 15 are denoted by the same reference numerals, and detailed description is omitted.

FIG. 1 is a plan view showing a liquid crystal display device and a test wiring using the method for testing a liquid crystal display device according to the present embodiment, and shows a storage capacitor for holding a potential between a pixel electrode 1 and a counter electrode 8. 9 are connected by the immediately preceding gate line 2.

The difference between the liquid crystal display device and the inspection wiring according to the present embodiment and the structure of the conventional example is that the gate wiring 2
In this case, the inspection wirings related to (1) are two of the first gate-side inspection wiring G1 and the second gate-side inspection wiring, and a total of six inspection wirings are provided.

As shown in FIG. 1, a source-side inspection wiring S1 and a source-side inspection wiring S
2. Source side inspection wiring S3, first gate side inspection wiring G
A total of six test wirings, ie, the first, second gate-side test wiring G2 and the counter electrode-side test wiring C, are drawn out of the display range of the liquid crystal display device and formed on the glass substrate on which the pixel electrodes 1 are formed. ing. The first gate-side inspection wiring G1 is connected to all the gate wirings 2 in the odd-numbered rows such as the first row, the third row, the fifth row,... Arranged along the gate wiring 2. The second gate-side inspection lines G2 are arranged in the second row, the fourth row, the sixth row,.
Are connected to all the gate lines 2 in the even-numbered rows as shown in FIG.

The source side inspection wiring S1 is connected to all of the source wirings 3 of the source wiring 3 where the red pixel electrode 1r and the green pixel electrode 1g are connected via the switching element 4. The source-side inspection wiring S2 is connected to all of the source wirings 3 of the source wiring 3 where the green pixel electrode 1g and the blue pixel electrode 1b are connected via the switching element 4. The source-side inspection wiring S3 is connected to all the source wirings 3 of the source wiring 3 where the blue pixel electrode 1b and the red pixel electrode 1r are connected via the switching element 4. The counter electrode side inspection wiring C is connected to the counter electrode 8.

FIG. 12 shows test lines G1, G2, S of a liquid crystal display device in which the test lines are formed on a glass substrate.
1 shows a configuration diagram of an inspection apparatus that applies a driving potential for inspection to 1, S2, S3, and C.

The inspection device 11 of the liquid crystal display device includes signal generation means 12 for outputting a driving potential for inspection to the inspection lines G1, G2, S1, S2, S3, and C, and a color to be displayed on the liquid crystal display device, that is, A selection switch (an example of a selection unit) 13 for selecting white, black, red, green, and blue; a signal generation unit 12; and the inspection wirings G1, G2, S1, S2, S3.
C is electrically connected to each other, and the driving potential corresponding to the color selected by the inspector by the switch 13 is transmitted from the inspection device 11 to the wiring cable 14.
Through the inspection wirings G1, G2, S1, S2, S3
C is applied.

In this inspection device 11, white, black, red,
The operation in the inspection method for displaying green and blue will be described with reference to the drawings. 2 is a white display, FIG. 3 is a black display, FIG. 4 is a red display, FIG. 5 is a green display, and FIG. 6 is a waveform diagram showing a driving potential of a driving signal output from the inspection apparatus 11 in an inspection of a blue display. It is. FIG. 7 to FIG.
FIG. 7 is a waveform diagram of the liquid crystal potential when the driving potential for inspection shown in FIGS. 7 shows the relationship when white display, FIG. 8 shows black display, FIG. 9 shows red display, FIG. 10 shows green display, and FIG. 11 shows the relationship when blue display is performed.

In FIGS. 2 to 6, the driving potentials applied to the first gate-side inspection wiring G1, the second gate-side inspection wiring G2, the source-side inspection wirings S1, S2, S3, and the counter electrode-side inspection wiring C are respectively shown. Vg1, Vg2, Vs1, Vs2,
Vs3 and Vc. Further, a drive potential sufficient to electrically open and close each switching element 4 is Von potential and V
off potential. Further, when the pixel electrode 1 reaches a predetermined potential while the switching element 4 is turned on and the pixel electrode 1 is turned on via the storage capacitor 9 to the immediately preceding gate wiring 2, the gate of the switching element 4 is turned off. The drive potential for driving the liquid crystal by canceling the fluctuation of the pixel potential of the pixel electrode 1 caused by the pixel potential of the pixel electrode 1 due to the parasitic capacitance existing between the drains and simultaneously controlling the level of the pixel potential of the pixel electrode 1 Are set to Ve + potential and Ve- potential. Further, the driving potentials Vs1, Vs
2, the center potential of the square wave at Vs3 is Vsc potential, and the DC wave level value at the driving potential Vc is Vcc potential. Note that the Vsc potential and the Vcc potential are the same potential.

7 to 11, the liquid crystal potentials of the odd-numbered red pixel electrode 1r, green pixel electrode 1g, and blue pixel electrode 1b connected to the first gate-side inspection wiring G1 are represented by V1r, V1g, and V1b. And the second gate side inspection wiring G
2, the green pixel electrode 1g and the blue pixel electrode 1 in the even-numbered rows.
b, the liquid crystal potential of the red pixel electrode 1r is V1g, V
1b and V1r.

[Operation 1] and [Operation 2] in FIGS.
The driving potential V of the gate-side inspection wires G1 and G2 in “operation 3”
The states of g1 and Vg2 will be described. <Operation 1> Drive potential Vg1 of first gate side inspection wiring G1
Is applied from the state of Voff potential or Ve + potential or Ve- potential once, and then Ve potential is applied.
+ Potential or Ve- potential is applied, and the second
It is assumed that Ve + potential or Ve- potential is applied to the gate-side inspection wiring G2.

According to this operation 1, the switching element 4 whose gate is connected to the first gate-side inspection wiring G1 is turned on from the off state for a predetermined period by the potential applied to the first gate-side inspection wiring G1. It turns off.

During the predetermined period, the second gate-side inspection wiring G
When the switching element 4 is turned off by the potential applied to the pixel element 2 and the pixel electrode 1 reaches a predetermined potential after the switching element 4 is turned on and the pixel electrode 1 reaches a predetermined potential, the gate of the switching element 4 The parasitic capacitance existing between the drains cancels the variation in the pixel potential of the pixel electrode caused by the pixel potential of the pixel electrode 1, and simultaneously controls the driving potential for driving the liquid crystal 10 by controlling the level of the pixel potential of the pixel electrode. The potential to be applied is applied via the storage capacitor 9 to the pixel potential of the pixel electrode 1 via the switching element 4 whose gate is connected to the first gate-side inspection wire G1. <Operation 2> Drive potential Vg2 of second gate-side inspection wiring G2
Is applied from the state of Voff potential or Ve + potential or Ve- potential once, and then Ve potential is applied.
+ Potential or Ve- potential is applied.
It is assumed that Ve + or Ve− potential is applied to the gate-side inspection wiring G1.

By the operation 2, the switching element 4 whose gate is connected to the second gate-side inspection line G2 is turned on from the off state for a predetermined period by the potential applied to the second gate-side inspection line G2. It turns off.

During the predetermined period, the first gate side inspection wiring G
When the switching element 4 is turned off by the applied potential to 1 and the pixel electrode reaches a predetermined potential while the switching element 4 is turned on,
The parasitic capacitance existing between the gate and the drain of the switching element 4 cancels the fluctuation of the pixel potential of the pixel electrode caused by the pixel potential of the pixel electrode, and simultaneously drives the liquid crystal 10 by controlling the level of the pixel potential of the pixel electrode. A potential for controlling the driving potential to be applied is applied to the pixel potential of the pixel electrode via the switching element 4 whose gate is connected to the second gate side inspection wiring via the storage capacitor 9. <Operation 3> It is assumed that the Voff potential is applied to both the first gate-side inspection wiring G1 and the second gate-side inspection wiring G2.

Note that the period of the operation 1 and the operation 2 is τa, and the period of Von in the driving potential Vg1 and the driving potential Vg2 is τb. The liquid crystal display device displays red, green, and blue when the potential difference between the pixel electrode 1 and the counter electrode 8 is small, and displays black when the potential difference is large. The potential difference between the pixel electrode 1 and the counter electrode 8 is maintained by the storage capacitor 9 from the time when the current is cut off until the time when the next conduction is performed.

A series of operations is repeated in the order of operation 1, operation 2, operation 3, operation 2, operation 1, and operation 3, and each of red, green, and blue is selected according to the color selected by the selection switch 13. The data signals Vs1, Vs2, Vs3 shown in FIGS. 2 to 6 are applied to the source side inspection wirings S1, S2, S3. Thus, a single color screen of white, black, red, green and blue is displayed.

The inspector inspects the liquid crystal display device on the displayed color monochromatic screen. After the inspection is completed, a part of the wiring pattern is blown by irradiating a laser beam along a cut portion T shown by a dashed line in FIG. 1 and connected to the source side inspection wirings S1, S2, S3 respectively. Connection with all the source lines 3, the first gate side inspection line G1
The connection between all the gate lines 2 connected to the first and second gate-side inspection lines G2 and the connection between the counter-electrode-side inspection line C and the counter electrode 8 are cut off, and the gate drive circuit 5 and the source drive Circuit 6, counter electrode drive circuit 7
To form a finished product. Until the electrical connection between each inspection wiring and the source wiring 3, the gate wiring 2, and the counter electrode 8 is cut off, the charge dispersing effect due to the short circuit prevents the switching element 4 from being damaged by static electricity and the switching characteristics from being defective. The effect can be expected.

As described above, the inspection lines connected to the gate line 2 are the first inspection line G1 and the second inspection line G2, and the first inspection line G1 and the second inspection line G2 are connected to each other.
By switching and applying the Von potential applied to the gate side inspection wiring G2 at a predetermined timing, white, black,
Red, green, and blue can be displayed, and a simple inspection can be realized.

Further, the gate lines 2 in the odd rows and the gate lines 2 in the even rows are separately connected to each other. When the storage capacitor 9 of each pixel electrode 1 is connected to the immediately preceding gate line 2, the source Von potential applied to the first gate-side inspection wiring G1 and the second gate-side inspection wiring G2 in consideration of the potential state between the pixel electrode 1 and the counter electrode 8 when a data signal is written from the wiring 3 to each pixel electrode 1 , The luminance difference between the pixel group of the line of the gate line 2 connected to the first gate-side inspection line G1 and the line pixel group of the gate line 2 connected to the second gate-side inspection line G2, that is, the gate This can be used to eliminate a feedthrough potential difference between the pixel potential of the odd-numbered row and the pixel potential of the even-numbered row. The feedthrough potential difference is defined as the moment when the charge stored in the liquid crystal capacitor and the storage capacitor 9 when the gate pulse is on is turned off due to the influence of the parasitic capacitance between the source and the gate of the switching element 4. The potential difference generated by redistribution to each capacitor. As a result, flicker, that is, flapping of the screen, can be suppressed, and a vertical cycle (field cycle), that is, a period from the time when data is written to a certain pixel to the time when the next data is written to the next pixel can be displayed at a frequency of 24 Hz or more. I have.

In this embodiment, there are two types of vertical periods, long and short, as shown in FIGS. 2 to 6 in terms of operation. However, 24 Hz or more refers to the longer vertical period.

Further, the drive voltage of the liquid crystal 10 existing between the pixel electrode 1 and the counter electrode 8 in the related art is applied to each source side inspection wiring S
1, S2, and S3, the driving potentials Vs1, Vs2, and Vs3 applied from the source wiring 3 are not only applied to the gate wiring 2 through the gate-side inspection wirings G1 and G2, but are not applied to the half amplitude value. The pixel electrode 1 is opposed to the pixel electrode 1 by the Ve + and Ve− potentials that cause a potential difference between the potential of the pixel electrode 1 and the potential of the counter electrode via the storage capacitors 9 of the driven potentials Vg1 and Vg2. Since the drive voltage of the liquid crystal 10 existing between the electrode 8 and the electrode 8 is obtained, the drive voltage of the liquid crystal 10 is increased only by the amplitude value of the source potential or the amplitude value of the source potential and the counter electrode potential. In comparison, when there is a bright point defect in the liquid crystal display device, the effect of making the bright point defect more noticeable in terms of visibility is produced.

To give an example, only the amplitude value of the source potential,
Alternatively, in a black display screen by driving to increase the driving voltage of the liquid crystal by the amplitude value of the source potential and the amplitude value of the counter electrode potential,
Although it can be seen only at a delicate halftone luminescent spot, it can be visually recognized as a perfect luminescent spot on the black display screen driven by the present invention, and a reduction in production loss due to missed inspection can be achieved.

Further, a period in which the Voff potential is applied to both the first gate-side inspection wiring G1 and the second gate-side inspection wiring G2 connected to the gate wiring 2, that is, a period of the operation 3, is set to the liquid crystal display device. This period is set to be equal to the period for maintaining the potential difference between the pixel electrode 1 and the counter electrode 8 in the actual driving when the driving circuit is formed. In this case, in the inspection method of the present invention, since there are two types of vertical periods, which are long and short, as described above, the longer Voff potential period is set to the pixel in actual driving when the liquid crystal driving circuit is formed in the liquid crystal display device. The period is set equal to the period during which the potential difference between the electrode 1 and the counter electrode 8 is maintained.

The reason for this is that the inspection by the inspection method of the present embodiment is positioned as an intermediate inspection in the process of manufacturing the liquid crystal display device, and is therefore to avoid an excessive inspection of defects due to the retention characteristics of the pixel potential. This makes it possible to recognize a point defect due to a variation in the holding characteristic of the pixel potential. Note that the retention characteristics depend on the off current of the switching element, the pixel capacitance, the leak current through the liquid crystal resistance, and the like.

During the period τb during which the switching element 4 is turned on by the potential applied to the first gate-side inspection wiring G1 or the second gate-side inspection wiring G2, the potential of the gate wiring 2 in the liquid crystal display device is at the Voff potential. From V to the second gate-side inspection wiring G1 or the second gate-side inspection wiring G2.
The on potential is applied, and the potential of the gate wiring 2 becomes ｛0.9 ×
(Von−Voff) + Voff｝, a period required for writing a data signal from the source line 3 to the pixel electrode 1 through the switching element 4, and a potential of the gate line 2 in the liquid crystal display device. From the state of the Von potential, the Voff potential is applied to the first gate-side inspection wiring G1 or the second gate-side inspection wiring G2, and the potential of the gate wiring 2 becomes {0.9 × (Voff−Von) + Von}.
Is equal to or longer than the sum of the falling period and the potential of the gate line 2 in the liquid crystal display device.
The Von potential is applied to the first gate-side inspection wiring G1 and the second gate-side inspection wiring G2 from the state of the f potential to form the gate wiring 2
, The period required to write the data signal from the source line 3 to the pixel electrode 1 through the switching element 4, and the potential of the gate line 2 in the liquid crystal display device being Von. The period is set to be less than the sum of the falling period when the potential Voff is applied to the first gate-side inspection wiring G1 or the second gate-side inspection wiring G2 from the potential state and the potential of the gate wiring 2 becomes Voff.

Drive potential Vg1 applied to gate wiring 2
The drive potential Vg2 is delayed due to the resistance and capacitance of the first and second gate-side inspection lines G1 and G2 and the gate line 2. If the time for turning on the switching element 4 is too long, Vo from the Von potential
Due to the delay in the waveform changing to the ff potential,
The switching element 4 cannot be cut off at a predetermined timing, and a failure due to the switching element 4 may not be detected. By setting the period τb, the correlation between the point defect due to the variation of the switching characteristics of the switching element 4, particularly the luminous point, and the driving screen at the time of forming the liquid crystal driving circuit, that is, the visibility of the luminous point coincides.

The period τa corresponding to the operation period of the operations 1 and 2 needs to be at least twice as long as the period τb for applying the Von potential. As described above, the driving potential Vg1 and the driving potential Vg2 applied to the gate wiring 2 are delayed due to the resistance and capacitance of the first gate-side inspection wiring G1, the second gate-side inspection wiring G2, and the gate wiring 2. Therefore, the potential at the time of switching of the driving potentials Vs1 to Vs3 of the source line 3 may be written to the pixel while the gate potential of the switching element 4 is not turned off. Therefore, the operation period τa needs to be at least twice as long as the period τb for applying the Von potential to secure a sufficient time.

The switching element 4 applied from the two gate-side inspection lines G1 and G2 and the three source-side inspection lines S1, S2 and S3 according to the resistance and capacitance of each line and each inspection line. The drive potentials Vg1 and Vg2 to be turned on and off and the data signals (drive potentials Vs1 to Vs3) written to the pixel electrode 1 are temporally delayed or advanced. The reason is that in the inspection before the completion of the liquid crystal display device, when the data signal from the source line 3 is written to the pixel electrode 1 through the switching element 4, a margin is maintained for the gate threshold value of the switching element 4. This is because the operation of writing the data signal from the source line 3 to the pixel electrode 1 is appropriately and reliably performed.

When two lines are provided like the first gate-side inspection line G1 and the second gate-side inspection line G2, the drive potential Vg1 of the odd-numbered row of gate lines 2 connected to the first gate-side inspection line G1 is provided. And the amplitude of the driving potential Vg2 applied to the even-numbered row of gate wirings 2 connected to the second gate-side inspection wiring G2, and the pixel electrode 1 of each pixel of the same color connected to the gate wiring 2 , It is necessary to make the liquid crystal voltage the same regardless of the odd and even rows. for that reason,
Each gate line 2 is connected to the first gate side inspection line G1 or the second gate side inspection line G1.
Connect to either of the gate side inspection wirings G2,
The other second gate-side inspection wiring G2 or the first gate-side inspection wiring G1 has a structure crossing on the wiring pattern.
The first gate-side inspection wiring G1 and the second gate-side inspection wiring G2 have the same resistance and capacitance.

In this embodiment, the liquid crystal display device in which the pixel electrodes 1 are arranged in a delta arrangement has been described as an example. However, the present invention is also applicable to a liquid crystal display device in which the pixel electrodes 1 are arranged in a stripe arrangement. And two inspection lines connected to the gate line 2 and the two gate-side inspection lines G
1 and the Von potential applied to the second gate-side inspection wiring G2 are applied at the timing described in the present embodiment,
White, black, red, green,
By applying a potential of a data signal for displaying blue to perform image inspection, a defect caused by opening / closing of the switching element 4, a defect caused by a characteristic defect of the switching element 4, and a variation in retention characteristics of pixel potentials Defect can be detected, and the visibility of the point defect is improved, thereby reducing the production loss due to missed inspection.

[0057]

As described above, according to the present invention, in a liquid crystal display device in which a storage capacitor is connected to the immediately preceding gate line, a red pixel electrode, a green pixel electrode, and a blue pixel are added. The electrodes are arranged in a delta arrangement, and even if two color pixel electrodes are connected to one source line via the switching element, the pixel electrodes are arranged in a simple manner as in a liquid crystal display device arranged in a stripe arrangement. Image inspection can be realized.

[Brief description of the drawings]

FIG. 1 is a plan view showing a configuration of a liquid crystal display device and a test wiring for realizing a liquid crystal display device test method according to an embodiment of the present invention.

FIG. 2 is a waveform chart showing a driving potential in the case of white display in the liquid crystal display device.

FIG. 3 is a waveform chart showing a driving potential in the case of black display in the liquid crystal display device.

FIG. 4 is a waveform diagram showing a driving potential in the case of red display in the liquid crystal display device.

FIG. 5 is a waveform chart showing a driving potential in the case of green display in the liquid crystal display device.

FIG. 6 is a waveform chart showing driving potentials in the case of blue display in the liquid crystal display device.

FIG. 7 is a waveform chart showing a liquid crystal potential for each pixel in the case of white display in the liquid crystal display device.

FIG. 8 is a waveform chart showing a liquid crystal potential of each pixel in the case of black display in the liquid crystal display device.

FIG. 9 is a waveform diagram showing a liquid crystal potential for each pixel in the case of red display in the liquid crystal display device.

FIG. 10 is a waveform diagram showing a liquid crystal potential for each pixel in the case of green display in the liquid crystal display device.

FIG. 11 is a waveform chart showing a liquid crystal potential for each pixel in the case of blue display in the liquid crystal display device.

FIG. 12 is a configuration diagram of a device for applying a driving charge to the liquid crystal display device.

FIG. 13 is a plan view showing a configuration of a conventional liquid crystal display device in which pixel electrodes are arranged in a delta arrangement.

FIG. 14 is a cross-sectional view showing a configuration of the conventional liquid crystal display device.

FIG. 15 is a plan view showing a configuration of a conventional liquid crystal display device in which pixel electrodes are arranged in a stripe array and a configuration of a test wiring.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 pixel electrode 1r red pixel electrode 1g green pixel electrode 1b blue pixel electrode 2 gate wiring 3 source wiring 4 switching element 5 gate drive circuit 6 source drive circuit 7 counter electrode drive circuit 8 counter electrode 9 storage capacitor 10 liquid crystal 11 inspection device 12 signal Generation means 13 Selection switch 14 Wiring cable C Counter electrode side inspection wiring G Gate side inspection wiring G1 First gate side inspection wiring G2 Second gate side inspection wiring S1, S2, S3 Source side inspection wiring T Cut section Vg1, Vg2, Vs1 , Vs2, Vs3, Vc Drive potential V1r, V1g, V1b Liquid crystal potential τa Period of operation 1 τb Period of turning on switching element

Claims (7)

[Claims] 1. An active matrix system in which a storage capacitor for holding a pixel potential of a pixel electrode of each pixel is connected to another gate line adjacent to a gate line for applying a potential to a gate of a switching element of the pixel. A first gate-side inspection wiring connected to a gate wiring for applying a potential to a gate of a switching element of each pixel in an odd-numbered row;
A second gate-side inspection wiring connected to a gate wiring for applying a potential to the gates of the switching elements in the even-numbered rows; an odd number is determined by a driving potential applied to the first gate-side inspection wiring and the second gate-side inspection wiring; An inspection method for a liquid crystal display device, wherein pixels in a row and pixels in an even row are separately driven. 2. An active matrix system in which a storage capacitor for holding a pixel potential of a pixel electrode of each pixel is connected to another gate line adjacent to a gate line for applying a potential to a gate of a switching element of the pixel. The method for inspecting a liquid crystal display device according to any one of claims 1 to 3, wherein three source-side inspection wires for each color connected to source wires of a column in which pixels for each color of red, green, and blue are arranged, or pixels of an odd-numbered row in a column. Three source-side inspection wirings connected to the same source wiring with the same combination of the color and the color of the pixel in the even-numbered row are provided, and the third inspection wiring is connected to the gate wiring that applies a potential to the gate of the switching element of each pixel in the odd-numbered row. 1 gate side inspection wiring,
A second gate-side inspection wiring connected to a gate wiring for applying a potential to the gates of the switching elements in an even-numbered row; and a pixel electrode of each pixel connected to a counter electrode provided so as to face a liquid crystal therebetween. A counter electrode side inspection wiring is provided, and a switching element whose gate is connected to the first gate side inspection wiring is turned on from a off state for a predetermined period by an applied potential to the first gate side inspection wiring, and then turned off. During the predetermined period, the second gate side inspection wiring
The operation of applying, via a storage capacitor, the pixel potential of the pixel electrode via a switching element in which the gate is connected to the first gate-side inspection line is referred to as operation 1, and the potential applied to the second gate-side inspection line. Accordingly, the switching element whose gate is connected to the second gate-side inspection wiring is turned on from the off state for a predetermined period, and then turned off.
The operation in which the gate applies the pixel potential of the pixel electrode via the storage element via the switching element connected to the second gate-side inspection line via the storage capacitor is referred to as operation 2, and the first gate-side inspection line and the second gate-side inspection When the operation of turning off all of the switching elements by the potential applied to the wiring is operation 3, a series of operations is repeated in the order of operation 1, operation 2, operation 3, operation 2, operation 1, and operation 3. In accordance with the selected color, a data signal is applied to each of the source side inspection wirings of red, green, and blue, and the inspection is performed by displaying a white, black, red, green, and blue color single color screen. Characteristic inspection method of liquid crystal display device. 3. A predetermined period in which a switching element is turned on by a potential applied to a first gate-side inspection wiring or a second gate-side inspection wiring, a potential for turning off the switching element is Voff, and the switching element is turned off. When the potential to be turned on is set to Von, the potential of the gate wiring in the liquid crystal display device is set to the potential Voff, and the potential Von is applied to obtain a voltage of 0.9 × (Von−
(Voff) + Voff}, a period required for writing a data signal from the source line to the pixel electrode via the switching element, and a Voff potential from the state where the potential of the gate line is Von. It is equal to or longer than a period obtained by adding a fall period of 0.9 × (Voff−Von) + Von｝, and a rise in which the potential of the gate wiring in the liquid crystal display device becomes Von by applying the Von potential from the state of Voff. A period required for writing data from the source line to the pixel electrode via the switching element, and a period in which the potential of the gate line in the liquid crystal display device is changed from Von to Voff.
3. The inspection method for a liquid crystal display device according to claim 1, wherein the period is set to be less than a period obtained by adding a falling period that becomes Voff by applying a potential. 4. The operation according to claim 1, wherein the period of the operation 1 and the operation 2 is a period that is at least twice as long as the predetermined period in which the switching element is turned on. Inspection method for liquid crystal display. 5. There are two types of periods in which each switching element is in an off state depending on the potential applied to the first gate-side inspection wiring and the second gate-side inspection wiring, and the longer one of the periods is set in the liquid crystal display device. 5. The method according to claim 1, wherein the period is equal to a period during which the pixel can hold the written potential. 6. An on-state and an off-state of said switching element applied from said two gate-side inspection wirings and said three source-side inspection wirings according to the resistance and capacitance of each said wiring and each said inspection wiring. Driving potential to be in a state,
6. The method according to claim 1, wherein a data signal to be written to the pixel electrode is delayed or advanced in time. 7. An active matrix system in which a storage capacitor for holding a pixel potential of a pixel electrode of each pixel is connected to another gate line adjacent to a gate line for applying a potential to a gate of a switching element of the pixel. In the inspection device for a liquid crystal display device, three source-side inspection wires of each color connected to source wires of a column in which pixels of red, green, and blue are arranged, or pixels of an odd-numbered row in a column. Three source-side inspection wirings connected to the same source wiring with the same combination of the color and the color of the pixel in the even-numbered row are provided, and the third inspection wiring is connected to the gate wiring that applies a potential to the gate of the switching element of each pixel in the odd-numbered row. 1 gate side inspection wiring,
A second gate-side inspection wiring connected to a gate wiring for applying a potential to the gates of the switching elements in the even-numbered rows; and a counter electrode provided so that all of the pixel electrodes of each pixel face each other with a liquid crystal interposed therebetween. Is provided, and a selecting means for selecting a color to be inspected is provided, and a driving potential according to the color selected by the selecting means is provided.
An inspection apparatus for a liquid crystal display device, further comprising signal generation means for applying the three source-side inspection wirings, the first and second gate-side inspection wirings, and the counter electrode-side inspection wirings.