JP3177702B2 - Inspection method of liquid crystal display - Google Patents

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. In the active matrix type liquid crystal display device, there are a device in which pixel electrodes for displaying red, green, and blue are arranged in a delta array and a device in which pixel electrodes are arranged in a stripe array.

FIG. 12 is a plan view showing the structure of a liquid crystal display device in which pixel electrodes are arranged in a delta arrangement, and FIG. 13 is a sectional view of the same. In the figure, a pixel electrode 1 comprising a red pixel electrode 1r for displaying red, a green pixel electrode 1g for displaying green, and a blue pixel electrode 1b for displaying blue is provided.
, A green pixel electrode 1g and a blue pixel electrode 1b are arranged in a delta arrangement, and a gate line 2 and a source line 3 are arranged so as to sew between the pixel electrodes 1. A switching element 4 typified by the TFT is disposed at the intersection of the gate line 2 and the source line 3, and a red pixel electrode 1 r, a green pixel electrode 1 g, and a blue pixel electrode 1 b depending on the potential applied to the gate line 2. And the source wiring 3 are electrically connected or disconnected. Pixel electrodes 1 of the same color are arranged in the same column every other wiring of the gate wiring 2, and pixel electrodes 1 of the same color adjacent via the gate wiring 2 are arranged shifted by 1.5 pixels.

In this delta arrangement, one source line 3 is connected via a switching element 4 to pixel electrodes 1 of two different colors per row, for example, a red pixel electrode 1r and a green pixel electrode 1g. I have. The same applies to the green pixel electrode 1g and the blue pixel electrode 1b, and the blue pixel electrode 1b and the red pixel electrode 1r. Reference numeral 5 denotes a gate drive circuit that applies a drive potential to the gate wiring 2, 6 denotes a source drive circuit that applies a drive potential to the source wiring 3, and 7 denotes a counter electrode drive circuit that applies a drive potential to the counter electrode 8. The circuit 5, the source drive circuit 6, and the counter electrode drive circuit 7 are arranged outside the screen. FIG. 13A shows AA ′ shown in FIG.
FIG. 13B is a sectional view taken along the line, and FIG.
It is sectional drawing which follows the B 'line. The pixel electrode 1 faces the counter electrode 8 with the liquid crystal 9 interposed therebetween, and displays characters and information by changing the ratio of transmitted light according to the potential difference between the pixel electrode 1 and the counter electrode 8.

FIG. 14 is a plan view showing a configuration of a liquid crystal display device in which the pixel electrodes 1 are arranged in a stripe arrangement and inspection wiring, and shows a state of inspection before completion.

Conventionally, in order to produce a liquid crystal display device with a high yield, a gate drive circuit 5, a source drive circuit 6, and a counter electrode drive circuit 7 are connected to all the gate lines 2, source lines 3, and counter electrodes 8, respectively. To apply a potential,
A defect detection inspection for displaying black, red, green and blue screens has been performed. 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 impossible to manufacture the probe. It becomes possible.
In the liquid crystal display device in which the pixel electrodes 1 are arranged in a stripe arrangement, in order to solve these disadvantages, as shown in FIG. Source-side inspection lines S1 connected to all of the source lines 3 to be connected, source-side inspection lines S2 connected to all of the source lines 3 corresponding to green, and source-side inspection lines connected to all of the source lines 3 corresponding to blue. Wiring S3 and counter electrode side inspection wiring C connected to counter electrode 8
A total of five inspection wirings are provided, and the inspection wirings are connected to the inspection circuit to perform an inspection, and then the inspection wirings are cut at the cutting portion T, thereby adopting a simple inspection configuration. .

[0007]

In such a conventional method for inspecting a liquid crystal display device, it is necessary to always inspect the switching element 4 in a conductive state. However, there is a problem that it is not possible to detect a defect caused by the characteristic defect described above. 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 decreases.

The present invention has been made to solve the above-mentioned problems, and can perform defect inspection without using a probe, and can display red, green, and blue even when the pixel electrodes 1 are arranged in a delta arrangement. An object of the present invention is to realize a method of inspecting a liquid crystal display device with improved inspection detection power.

Further, even when the pixel electrodes 1 are arranged in a stripe arrangement, a defect caused by the switching element 4, a defect caused by a characteristic defect of the switching element 4, and a defect caused by variation in holding characteristics of the pixel potential. It is an object of the present invention to realize a method of inspecting a liquid crystal display device capable of detecting a liquid crystal display device.

[0010]

According to the present invention, there is provided an inspection method for a liquid crystal display device, wherein two inspection lines are connected to a gate line for each row: a first gate side inspection line and a second gate side inspection line. Gate wirings are alternately connected to the first gate-side inspection wiring and the second gate-side inspection wiring every other row, and the switching element is turned on from the off state for a predetermined period by a potential applied to the first gate-side inspection wiring. Thereafter, the switching element is turned off, and the switching element is turned off by a potential applied to the second gate-side inspection wiring during a predetermined period.
The switching element is turned on from the off state by a potential applied to the second gate-side inspection wiring for a predetermined period and then turned off, and during the predetermined period, the switching element is turned on by the potential applied to the first gate-side inspection wiring. When the operation of turning off the switching element is defined as operation 2 and the operation of turning off each switching element by the potential applied to the first gate-side inspection wiring and the second gate-side inspection wiring is defined as operation 3, Action 1, Action 2, Action 3, Action 2, Action 1, Action 3
,... Are repeatedly performed to display a single-color screen of white, black, red, green, and blue for inspection.

According to the present invention, even when the pixel electrodes are arranged in a delta arrangement, a single color display of red, green, and blue can be performed, and a simple inspection can be performed. In addition, it is possible to detect a defect due to the switching element, a defect due to a characteristic defect of the switching element, and a defect due to a variation in pixel potential holding characteristics.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS According to the first aspect of the present invention, pixels of three colors of red, green, and blue are periodically and repeatedly arranged in a horizontal row, and pixels of the same color are arranged in a vertical column. And an active matrix type liquid crystal display device in which pixel electrodes of each pixel in the column are connected to a source line in each column via a switching element controlled by a gate potential. In the above, the red source-side inspection wiring connected to all the source wirings in the column where the red pixels are arranged, the green source-side inspection wiring connected to all the source wirings in the column where the green pixels are arranged, and the blue pixels are arranged. A blue source-side inspection line connected to all of the source lines in the selected column, a first gate-side inspection line connected to all of the gate lines that apply a potential to the gates of the switching elements in odd-numbered rows, A second gate-side inspection line connected to all of the gate lines that apply a potential to the gate of the switching element; and a counter electrode side connected to a counter electrode provided so that all of the pixel electrodes face each other with a liquid crystal interposed therebetween. An inspection wiring, and the switching element is turned on from the off state by a potential applied to the first gate-side inspection wiring for a predetermined period and then turned off, and during the predetermined period, the switching element is connected to the second gate-side inspection wiring. The operation of turning off the switching element by the applied potential is referred to as an operation 1, and the switching element is turned on from the off state for a predetermined period by the applied potential to the second gate-side inspection wiring, and then turned off, and then is turned off for the predetermined period. During the operation, the operation of turning off the switching element by the potential applied to the first gate side inspection wiring is referred to as operation 2, and the operation of the first gate side inspection wiring is performed. When the operation 3 to operation of the both turned off the switching element by the wiring and the potential applied to the second gate side inspection line, operation
By repeating a series of operations in the order 1, 1, 2, 3, 2, 1, 3, the inspection is performed by displaying the white, black, red, green, and blue color monochrome screens. After the inspection, the connection between each of the source-side inspection wirings and all the source wirings respectively connected thereto, the first gate-side inspection wiring and the second gate-side inspection wiring, and all the gate wirings respectively connected thereto. And a connection between the counter electrode side inspection wiring and the counter electrode is disconnected.

According to the present invention, it is possible to display and inspect a simple and uniform screen in the inspection before the completion of the liquid crystal display devices arranged in the stripe arrangement, and to inspect the driving screen at the time of forming the liquid crystal driving circuit. In comparison, the liquid crystal display device has an effect that the correlation of defective visual recognition is extremely high.

According to a second aspect of the present invention, pixels of three colors of 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 arranged in even rows. It has a pixel array configuration of a delta arrangement provided by being shifted by 5 pixels in the horizontal direction, and has pixel electrodes of pixels in the same column for every odd-numbered row and 0.5 pixels from the column of the odd-numbered row in the same column for every even-numbered row. In an active matrix type liquid crystal display device connected to a source line for each column of the odd-numbered row via a switching element controlled by a gate potential, a pixel electrode of a pixel shifted to A source-side inspection wiring connected to all of the source wirings having the same combination of the pixel color and the pixel color in the even-numbered row is provided for each combination, and the gate of the switching element in the odd-numbered row is electrically connected to the gate. A first gate-side inspection line connected to all of the gate lines that apply a voltage, a second gate-side inspection line connected to all of the gate lines that supply a potential to the gates of the switching elements in an even-numbered row, and all of the pixel electrodes And a counter electrode-side inspection wire connected to a counter electrode provided so as to face the liquid crystal, and the switching element is turned on from the off state for a predetermined period by a potential applied to the first gate-side inspection wire. Thereafter, the switching element is turned off, and the switching element is turned off by a potential applied to the second gate-side inspection wiring during a predetermined period.
The switching element is turned on from the off state by a potential applied to the second gate-side inspection wiring for a predetermined period and then turned off, and during the predetermined period, the switching element is turned on by the potential applied to the first gate-side inspection wiring. When the operation of turning off the switching element is an operation 2, and the operation of turning off both of the switching elements by the potential applied to the first gate-side inspection wiring and the second gate-side inspection wiring is an operation 3, Action 2, Action 3, Action 2, Action 1, Action 3
By repeating a series of operations in the order of
Inspection is performed by displaying a single color screen of black, red, green, and blue, and after the inspection, the connection between the three source-side inspection wirings and all the source wirings connected to the three source-side inspection wirings, A liquid crystal display that disconnects the connection between the first gate-side inspection wiring and the second gate-side inspection wiring and all of the gate wirings respectively connected thereto, and the connection between the counter electrode-side inspection wiring and the counter electrode. This is an inspection method of the apparatus.

In the present invention, it is possible to easily and uniformly display and inspect a uniform screen in the inspection before the completion of the liquid crystal display devices arranged in the delta arrangement. In comparison, the liquid crystal display device has an effect that the correlation of defective visual recognition is extremely high.

According to a third aspect of the present invention, as the predetermined period in which the switching element is turned on by the potential applied to the first gate side inspection wiring or the second gate side inspection wiring,
When the potential for turning off the switching element is Voff and the potential for turning on the switching element is Von, the potential of the gate wiring in the liquid crystal display device is 0.9 × (Von-Voff) + Voff
, A period required to write a data signal from the source wiring to the pixel electrode via the switching element, and a potential Voff from the state where the potential of the gate wiring is Von is 0.9 × (Voff -Von) is equal to or longer than a period obtained by adding a falling period of + Von, and a rising period in which the potential of the gate line in the liquid crystal display device becomes Von by applying the Von potential from the state of Voff; A period required to write data from a source line to a pixel electrode via a pixel electrode, and a period obtained by adding a falling period in which the potential of the gate line in the liquid crystal display device becomes Voff by applying the Voff potential from the state of Von. A method for inspecting a liquid crystal display device according to claim 1 or claim 2.

In the present invention, the inspection before completion of the liquid crystal display device has an effect of improving the correlation and matching of the defective visual recognition of the liquid crystal display device as compared with the driving screen when the liquid crystal driving circuit is formed.

According to a fourth aspect of the present invention, the period of the operation 1 and the period of the operation 2 is set to be at least twice as long as the predetermined period when the switching element is turned on.
An inspection method for a liquid crystal display device according to any one of claims 3 to 3.

In the present invention, in the inspection before 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. This has an operation of appropriately and reliably performing an operation of writing a data signal from a source wiring to the pixel electrode.

According to a fifth aspect of the present invention, 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. 5. A method for testing a liquid crystal display device according to claim 1, wherein a period is set to be equal to a period during which a pixel in the liquid crystal display device can hold a written potential.

In the present invention, the inspection before completion of the liquid crystal display device has an effect of increasing the correlation and consistency of the visual recognition of the defect of the liquid crystal display device as compared with the driving screen when the liquid crystal driving circuit is formed.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the method for inspecting a liquid crystal display device according to the present invention will be described below with reference to the drawings.

FIG. 1 is a plan view showing a liquid crystal display device in which pixel electrodes 1 in this embodiment are arranged in a delta arrangement and inspection wiring. The same components as those in the conventional example shown in FIGS. 12 to 14 are denoted by the same reference numerals, and detailed description is omitted. The configuration of the present embodiment is different from that of the conventional example in that the inspection wiring relating to the gate wiring 2 is two, that is, the first gate inspection wiring G1 and the second gate inspection wiring G2, and a total of six inspection wirings are provided. It is in.

In FIG. 1, the source-side inspection wiring S1, the source-side inspection wiring S2, the source-side inspection wiring S3, the first gate-side inspection wiring G1, the second gate-side inspection wiring G2, and the counter electrode-side inspection wiring C have a total of six. The inspection wiring is drawn out of the display range of the liquid crystal display device and formed on the glass substrate on which the pixel electrode 1 is formed. The first gate-side inspection wiring G1 is arranged in the first row arranged along the gate wiring 2,
The third row, the fifth row,... Are connected to all the gate lines 2 in the odd rows. On the other hand, the second gate-side inspection wiring G2 is connected to all the gate wirings 2 in the even-numbered rows, such as the second row, the fourth row, the sixth row, ... arranged along the gate wiring 2. It is connected.

The source side inspection wiring S 1 is connected to all the source wirings 3 of the source wiring 3 where the red pixel electrode 1 r and the green pixel electrode 1 g 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 of 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.

The operation of the inspection method for displaying white, black, red, green and blue in the above configuration will be described with reference to the drawings. 2 is a waveform diagram showing driving potentials in white display, FIG. 3 is black display, FIG. 4 is red display, FIG. 5 is green display, and FIG. 6 is a drive potential in blue display. In the figure, drive potentials applied to a first gate-side inspection wire G1, a second gate-side inspection wire G2, a source-side inspection wire S1, S2, S3, and a counter electrode-side inspection wire C are denoted by Vg1, Vg2, Vs1, respectively. Vs2, V
s3 and Vc. The driving potential Vg1 and the driving potential Vg2 sufficient to electrically open and close each switching element 4 are defined as Von potential and Voff potential.

The Von potential is applied once after the drive potential Vg1 of the first gate-side inspection wiring G1 is the Voff potential, and then the Voff potential is applied. During that period, the Voff potential is applied to the second gate-side inspection wiring G2. The state in which the potential is applied is referred to as operation 1, and the drive potential Vg2 of the second gate-side inspection wiring G2 is applied to the Voff potential once from the state of the Voff potential, and then the Voff potential is applied. Operate in a state where the Voff potential is applied to the gate side inspection wiring G1.
The state in which the Voff potential is applied to both the first gate-side inspection wiring G1 and the second gate-side inspection wiring G2 is referred to as operation 3. Note that the cycle of the operation 1 and the operation 2 is τa, and the driving potential Vg1 and the driving potential Vg2
The on period is τb.

This 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,
When the potential difference is large, black is displayed, and the liquid crystal 9 maintains the potential difference between the pixel electrode 1 and the counter electrode 8 from the time when the switching element 4 is cut off to the time when the liquid crystal 9 is next conducted.

FIGS. 7 to 11 show the red pixel electrodes 1r and 1r in the odd-numbered rows connected to the first gate-side inspection wiring G1 when the driving potential for the inspection shown in FIGS. 2 to 6 is applied.
The liquid crystal potentials V1r, V1g, V1b of the green pixel electrode 1g and the blue pixel electrode 1b, and the even-numbered green pixel electrode 1g and the blue pixel electrode 1b connected to the second gate-side inspection wiring G2, respectively.
The liquid crystal potentials V1g, V1b, V of the red pixel electrode 1r
FIG. 4 is a waveform diagram showing 1r, and also shows the relationship between the display color of each pixel electrode and the display color of the entire screen. here,
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.

As described above, the inspection lines connected to the gate line 2 are the first gate-side inspection line G1 and the second gate-side inspection line G2, and the first gate-side inspection line G1 and the second gate-side 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. Since the odd-numbered gate wiring 2 and the even-numbered gate wiring 2 are connected separately, the pixel group of the line of the gate wiring 2 connected to the first gate-side inspection wiring G1 and the second gate This can be used to eliminate the luminance difference between the pixel group of the line of the gate line 2 connected to the side inspection line G2, that is, the field-through potential difference between the pixel potential of the odd gate row and the pixel potential of the even gate row. The field-through potential difference is defined as the electric charges charged in the liquid crystal capacitance and the storage capacitance when the gate pulse is turned on, respectively, at the moment when the gate pulse is turned off due to the influence of the parasitic capacitance between the source and the gate of the switching element 4. Is a potential difference generated by being redistributed into the capacitors. 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, becomes 24 Hz or more, enabling screen display without flicker. I have. Note that, in the present embodiment,
As can be seen from FIGS. 2 to 6, there are two types of vertical periods, long and short, but 24 Hz or more refers to the longer vertical period.

Further, the 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, the period of the operation 3, is set to the liquid crystal display device. The 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 period of the Voff potential corresponds to the pixel electrode 1 in driving when the liquid crystal driving circuit is formed in the liquid crystal display device. And a period during which the potential difference between the electrode and the counter electrode 8 is maintained. The reason is that the inspection according to the inspection method of the present embodiment is positioned as an intermediate inspection in the manufacturing process of the liquid crystal display device, and therefore, is 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. The retention characteristics are as follows:
It depends on the off current of the switching element, the leak current through the pixel capacitance and 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 changed from the state of the Voff potential. A Von 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 × (Von−V
off) A rising period when the voltage becomes + 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 state where the potential of the gate line 2 in the liquid crystal display device is the Von potential. From the first gate side inspection line G1 or the second gate side inspection line G2 to Voff
By applying a potential, the potential of the gate wiring 2 becomes 0.9 × (Voff
−Von) The potential of the gate line 2 in the liquid crystal display device is equal to or longer than the period obtained by adding the falling period when the voltage becomes + Von.
From the state of f, the Von potential is applied to the first gate-side inspection wiring G1 and the second gate-side inspection wiring G2, and the rising period when the potential of the gate wiring 2 becomes the Von potential, and the pixel electrode 1 through the switching element 4 The period required for writing the data signal from the source line 3 to the gate line 2 in the liquid crystal display device and the potential of the gate line 2 in the liquid crystal display device are set to Von potential.
The period is set to be less than the sum of the falling period when the potential of the gate wiring 2 becomes Voff by applying the f potential.

The drive potential Vg1 and the drive potential Vg2 applied to the gate line 2 are delayed due to the resistance and capacitance of the first and second gate-side test lines G1 and G2 and the gate line 2. If the time during which the switching element 4 is turned on is too long, the Von potential changes to Voff
When a delay occurs in the waveform to be changed to the 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. As a result, the correlation between the point defect due to the variation in the switching characteristics of the switching element 4, particularly the bright spot, and the actual driving screen at the time of forming the liquid crystal driving circuit, that is, the visibility of the bright spot coincides.

Τa which is the operation period of operation 1 and operation 2
Needs to be at least twice the period τb during which the Von potential is applied. As described above, the drive potential Vg1 and the drive potential Vg2 applied to the gate line 2 are delayed due to the resistance and capacitance of the first gate-side inspection line G1, the second gate-side inspection line G2, and the gate line 2. Therefore, the potential at the time of switching the drive 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 and 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.

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 gate lines 2 connected to the first gate-side inspection line G1 is provided. And the drive potential V applied to the gate lines 2 in the even-numbered rows connected to the second gate-side inspection line G2.
It is necessary to make the amplitude of g2 the same and make the liquid crystal potential of the pixel electrode 1 of each pixel of the same color connected to the gate wiring 2 the same regardless of the odd-numbered row and the even-numbered row. Therefore, each gate line 2 is connected to either the first gate-side inspection line G1 or the second gate-side inspection line G2, and is connected to the other second gate-side inspection line G2 or the first gate-side inspection line G1. The first and second gate-side inspection lines G1 and G2 have a structure of intersecting on the pattern.
Are made to have the same resistance and capacitance.

After the completion of the inspection, 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. The electrical connection between the gate drive circuits 5,
The source drive circuit 6 and the counter electrode drive circuit 7 are formed to finish the product.

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 effective for 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 first gate side inspection lines G1 and the second
A Von potential applied to the gate-side inspection wiring G2 is applied at the timing described in this embodiment, and a data signal for displaying white, black, red, green, and blue on the source-side inspection wirings S1, S2, and S3. Of the switching element 4, a failure due to a characteristic failure of the switching element 4, and a failure due to a variation in the holding characteristic of the pixel potential. it can.

[0038]

As described above, according to the inspection method of the liquid crystal display device of the present invention, the first gate side inspection wiring connected to the gate wiring of the odd-numbered switching elements and the gate wiring of the even-numbered switching elements are connected. The connected second gate side inspection wiring is provided to drive the pixels in the odd-numbered rows and the pixels in the even-numbered rows separately, so that the red pixel electrode, the green pixel electrode, and the blue pixel electrode are arranged in a delta arrangement. Even if two color pixel electrodes are connected to one source line via the switching element, the white and white pixels for inspection are similar to the liquid crystal display device in which the pixel electrodes are arranged in a stripe array.
A single color display of black, red, green, and blue can be performed, and a liquid crystal display device that can perform simple image inspection can be realized.

Further, irrespective of whether the pixel electrodes are arranged in a delta arrangement or a stripe arrangement, a defect caused by the opening and closing of the switching element, a defect caused by a characteristic defect of the switching element, and retention of the pixel potential. A defect due to variation in characteristics can be detected, and an inspection can be performed with improved correlation with an actual driving screen when a liquid crystal driving circuit is formed.

[Brief description of the drawings]

FIG. 1 is a plan view showing a configuration of a liquid crystal display device and a test wiring in one embodiment of a test method of a liquid crystal display device of the present invention.

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

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

FIG. 4 is a waveform chart showing a driving potential in the case of red display in the embodiment.

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

FIG. 6 is a waveform chart showing a driving potential in the case of blue display in the embodiment.

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

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

FIG. 9 is a waveform chart showing the liquid crystal potential of each pixel in the case of red display in the embodiment.

FIG. 10 is a waveform chart showing the liquid crystal potential of each pixel in the case of green display in the embodiment.

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

FIG. 12 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. 13 is a cross-sectional view showing the conventional configuration.

FIG. 14 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]

 DESCRIPTION OF SYMBOLS 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 liquid crystal 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 Switching element ON period τb Operation 1 period

Continuation of the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G02F 1/13 101 G02F 1/136 G02F 1/133 G09G 3/36

Claims (5)

(57) [Claims] 1. A horizontal row has pixels of three colors of red, green and blue periodically and repeatedly arranged, and a vertical column has a pixel array configuration of a vertical stripe in which pixels of the same color are arranged. In an active matrix type liquid crystal display device, a pixel electrode of each pixel of the column is connected to a source line of the column via a switching element controlled by a gate potential, a source line of a column where red pixels are arranged. , A green source-side test wire connected to all of the source wires in the column where the green pixels are arranged, and a blue wire connected to all of the source wires in the column where the blue pixels are arranged. Source-side inspection wiring, a first gate-side inspection wiring connected to all of the gate wirings that apply potentials to the gates of the odd-numbered switching elements, and a gate of the even-numbered switching elements. A second gate-side inspection line connected to all of the gate lines that apply a potential; and a counter electrode-side inspection line connected to a counter electrode provided so that all of the pixel electrodes face each other with a liquid crystal interposed therebetween. The switching element is turned on from the off state by a potential applied to the first gate-side inspection wiring for a predetermined period and then turned off, and during the predetermined period, the switching element is turned on by the potential applied to the second gate-side inspection wiring. The operation of turning off is referred to as operation 1, and the switching element is turned on from the off state for a predetermined period by the potential applied to the second gate-side inspection wiring, and then turned off, and during the predetermined period, the first gate-side inspection is performed. The operation of turning off the switching element in accordance with the potential applied to the wiring is referred to as operation 2, and the first gate-side inspection wiring and the second gate-side inspection wiring are marked. When the operation of turning off all of the switching elements by the applied potential is defined as an operation 3, by repeating a series of operations 1, 2, 3, 2, 1 and 3, Inspection is performed by displaying a single color screen of white, black, red, green and blue, and after the inspection, connection between each of the source side inspection wirings and all the source wirings connected thereto, a first gate Inspection method for a liquid crystal display device in which the connection between the side inspection wiring and the second gate-side inspection wiring and all the gate wirings connected thereto and the connection between the counter electrode-side inspection wiring and the counter electrode are cut off. . 2. Pixels of three colors of red, green, and blue are periodically and repeatedly arranged in odd-numbered rows in the horizontal direction, and the same arrangement as the odd-numbered rows is arranged in even-numbered rows by 1.5 pixels in the horizontal direction. It is provided with a pixel array configuration of a delta arrangement provided in a staggered manner, and a pixel electrode of a pixel arranged in the same column for every odd-numbered row and a pixel electrode of a pixel shifted in the horizontal direction by 0.5 pixel from the column of the odd-numbered row in the same column for every even-numbered row. In an active matrix type liquid crystal display device connected to source lines for each column of the odd-numbered row via a switching element controlled by a gate potential, the color of the pixel of the odd-numbered row in the column and the color of the even-numbered row Source-side inspection lines connected to all of the source lines having the same combination of pixel colors are provided for each of the combinations, and all of the gate lines that apply a potential to the gates of the switching elements in odd rows are provided. A first gate-side inspection line connected to all the gate electrodes, a second gate-side inspection line connected to all of the gate lines that apply a potential to the gates of the even-numbered switching elements, and all of the pixel electrodes sandwiching a liquid crystal. A counter electrode-side inspection wiring connected to a counter electrode provided so as to face the switching element, and the switching element is turned on from the 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 operation of turning off the switching element by the potential applied to the second gate-side inspection wiring is referred to as operation 1, and the switching element is turned off by the potential applied to the second gate-side inspection wiring for a predetermined period of time. The switching element is turned off after being turned on, and during a predetermined period, the switching element is turned off by a potential applied to the first gate-side inspection wiring. The work and operation 2, when the work 3 operations to both turned off the switching element by applying potential to the first gate-side inspection line and the second gate side inspection line, the operation 1, operation 2, the operation
By repeating a series of operations in the order of 3, operation 2, operation 1, and operation 3, a white, black, red, green, and blue color single-color screen is displayed for inspection, and after the inspection,
Connection between the three source-side inspection lines and all the source lines connected thereto, and all of the gate lines respectively connected to the first gate-side inspection line and the second gate-side inspection line And a connection between the counter electrode side inspection wiring and the counter electrode is disconnected. 3. As a predetermined period in which the switching element is turned on by a potential applied to the first gate-side inspection wiring or the second gate-side inspection wiring, the potential for turning off the switching element is set to Voff, and the switching element is turned on. Is set to Von, the potential of the gate line in the liquid crystal display device is set to Voff potential from the state of Voff potential, and the potential of Von is set to 0.
A rising period of 9 × (Von−Voff) + Voff,
A period required to write a data signal from a source wiring to a pixel electrode via the switching element, and a Voff potential from a state where the potential of the gate wiring is Von to 0.
It is equal to or longer than a period obtained by adding a falling period of 9 × (Voff−Von) + Von, and when the potential of the gate line in the liquid crystal display device is Voff, the potential Von is applied and Von is applied.
And a period required to write data from the source wiring to the pixel electrode via the switching element, and a potential of the gate wiring in the liquid crystal display device becomes Voff by applying an off potential from the state of Von. 3. The method for inspecting a liquid crystal display device according to claim 1, wherein the period is set to be less than a period obtained by adding the falling period. 4. The liquid crystal display according to claim 1, wherein a 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. Equipment inspection method. 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 inspection method for a liquid crystal display device according to claim 1, wherein the period is set equal to a period during which the pixel can hold the written potential.