JPH05134629A - Active matrix type liquid crystal display panel and driving method therefor - Google Patents

Abstract

PURPOSE:To minimize the degradation in display quality due to flickering by providing TFTs in such a manner that picture element electrodes of odd Columns are selected by th i-the gate bus line and the picture element electrodes of the even columns are selected by the (i+1)-th gate bus line in the i-th now. CONSTITUTION:This panel is constituted of the picture element electrodes 171 to 176, 181 to 186, 191 to 196, the TFTs 201 to 206, 211 to 216, 221 to 226, the gate bus lines 231 to 234, data bus lines 241 to 246, and gate pulses G1 to G4. The delay time of integer-times of one horizontal period is provided between the data to be impressed to the picture element electrodes of the odd columns and the data to be impressed to the even columns. The data is supplied by inverting the gradation thereof at every one horizontal period in such a manner that the potential of the driving common electrode is inverted in every one horizontal period and the gradetion of the data supplied to the respective picture elements on the next one frame or the next frame. As a result, the low-voltage AC driving is executed and the polarity inversion of every one picture element is executed.

Description

Detailed Description of the Invention

[0001]

The present invention relates to a liquid crystal display (Liquid Cry).
The present invention relates to a so-called active matrix liquid crystal display panel in which a switching element is provided for each pixel in a stal display) panel, and a driving method thereof.

[0002]

2. Description of the Related Art Conventionally, as an active matrix type liquid crystal display panel, one having a partial perspective view shown in FIG. 27 is known.

In the figure, 1 and 2 are glass substrates, 3 and 4 are deflection plates, 5 is a liquid crystal, 6 is a pixel electrode, 7 is a thin film transistor (hereinafter referred to as TFT) forming a switching element, and 8 is a gate bus line (scanning). Electrodes), 9 are data bus lines (signal electrodes), 10 is a common electrode, 11 is a color filter, R is a red portion, G is a green portion, and B is a blue portion.

In this active matrix type liquid crystal display panel, the O of the TFT 7 is turned on by a gate pulse applied to the gate bus line 8 via a gate driver (not shown).
It is assumed that N and OFF are controlled to write the video signal from the data bus line 9 to the selected pixel, and control is performed to write one line (one row) in one horizontal period. To be done.

In addition, in such an active matrix type liquid crystal display panel, in order to prevent deterioration of the liquid crystal 5, so-called AC driving is generally performed so that the voltage of the DC component is not applied to the liquid crystal 5 for a long time. Target.

Conventionally, as a method of performing such an AC drive,
A method of applying a positive video signal and a negative video signal to the pixel electrode 6 alternately while keeping the voltage applied to the common electrode 10 constant has been performed. In this case, unlike the case of the DC drive system, it is necessary to configure a data driver capable of outputting a voltage level that is twice the number of gradations.

Such a data driver is usually constructed by arranging a plurality of driver ICs. FIG. 28 is a block diagram showing an example of such a driver IC for AC drive. In the figure, 12 is a shift register, 13 is a data register, 14 is a latch circuit, 15 is a selector, SP is a start pulse, CL is a clock pulse, LE is a latch pulse, and V1 to V16 are DC voltages having different voltage levels. is there.

The driver IC inputs a video signal of RGB three colors which has been digitized, stores it in the data register 13 for each pixel by the shift register 12, and then stores the video signal stored in the data register 13. Is latched by the latch circuit 14, and the DC voltage corresponding to the video signal of each pixel latched by the latch circuit 14 is selected by the selector 15, and the selected DC voltage of each pixel is transferred to the pixel via the data bus line. It is to supply to the electrodes.

By the way, in order to carry out AC driving of the active matrix type liquid crystal display panel, as described above, a voltage level which is twice the number of gradations is required. In order to do so, 16 DC levels of voltage level are required.

Therefore, it is difficult to operate the data driver with low power consumption, and the number of analog switches to be provided in the selector 15 needs to be twice the number of gradations for one output. It was also difficult to reduce the chip size.

Therefore, in recent years, in order to solve such a problem, the number of voltage levels to be supplied to each pixel electrode is changed by changing the potential of the common electrode at the timing of AC driving so as to be the same as in the case of DC driving. There has been proposed a low-voltage AC driving method capable of controlling the voltage level.

For example, as shown in FIG. 29, the voltage level of the video signal supplied to each pixel electrode is 0-5.
In the case of being in the range of [V], the potential of the common electrode is set to −2 [V] during positive drive, and the potential of the common electrode is set to 7 [V] during negative drive. is there.

According to such a low-voltage AC driving method, for example, in the case of displaying 8 gradations, the DC voltage of 8 kinds of voltage levels, which is the same as the number of gradations, should be prepared in spite of the AC driving. Sufficiently, it is not necessary to prepare 16 kinds of DC voltage having twice the number of gradations. Therefore, it is possible to reduce the power consumption of the driver IC forming the data driver and reduce the chip size.

[0014]

By the way, in the AC driving method, the polarity is inverted every frame or field, and one line (one line) in the gate bus line direction.
The polarity can be inverted for each line, the polarity can be inverted for each line (one column) in the data bus line direction, and the polarity can be inverted for each pixel.

However, since the T (transmittance) -V (applied voltage) characteristic of the pixel is asymmetric between the positive polarity driving and the negative polarity driving, flicker occurs and human eyes perceive flicker. There is a problem that the flicker becomes conspicuous especially in the AC driving method in which the polarity is inverted for each frame or field. Therefore, in the AC driving method in which the potential of the common electrode is not changed, the AC driving for each line or the AC driving for each pixel is usually performed.

On the other hand, when low-voltage AC driving for changing the potential of the common electrode is performed, the voltage is 1 in the gate bus line direction.
Although the polarity can be inverted for each line, the polarity cannot be inverted for each line in the data bus line direction, and the polarity cannot be inverted for each pixel. This is because the voltage of the common electrode is changed corresponding to the polarity reversal.

As described above, the low-voltage AC driving method for changing the potential of the common electrode can reduce the power consumption of the driver IC constituting the data driver and the chip size. As long as the conventional active matrix type liquid crystal display panel shown in FIG. 27 is used,
There is a problem in that the polarity inversion cannot be performed for each pixel and the deterioration of display quality due to flicker cannot be minimized.

In view of the above point, the present invention can perform low-voltage AC driving, perform polarity inversion for each pixel, and make adjacent pixels have different drive polarities, thereby reducing display quality due to flicker. It is an object of the present invention to provide an active matrix type liquid crystal display panel which can be minimized and a driving method thereof.

[0019]

In the present invention, an active matrix type liquid crystal display panel according to the first invention comprises a first gate bus line, a first row pixel electrode, a second gate bus line and a second row. Pixel electrode ... An nth (where n = positive integer) gate bus line, an nth row of pixel electrodes and an (n + 1) th gate bus line are sequentially arranged, and an ith row (where 1 ≦ i ≦ In n), the odd-numbered or even-numbered pixel electrodes are selected by the i-th gate bus line, and the pixel electrodes other than the pixel electrodes selected by the i-th gate bus line are the (i + 1) th gate bus line. A switching element is provided so as to be selected by.

In the active matrix type liquid crystal display panel according to the second aspect of the present invention, two gate bus lines per row are provided so as to sandwich the pixel electrodes, and in each row, the pixel electrodes in odd columns or even columns are arranged. Of the two gate bus lines, one of the two gate bus lines is selected by one of the two gate bus lines, and the pixel electrode other than the pixel electrode selected by the one of the two gate bus lines is the other gate bus line. A switching element is provided so as to be selected according to the line.

In the active matrix type liquid crystal display panel according to the third aspect of the present invention, two gate bus lines per row are provided so as to sandwich a pixel electrode, and the two gate bus lines are provided per pixel electrode. It is configured such that two switching elements that can be controlled by one or the other of the gate bus lines are provided and one of the switching elements is made non-conductive.

[0022]

In the active matrix type liquid crystal display panel according to the first aspect of the present invention, for example, an integer multiple of one horizontal period is provided between the data applied to the pixel electrodes in the odd columns and the data applied to the pixel electrodes in the even columns. In addition to having a delay time, the potential of the driving common electrode is inverted every horizontal period, and in the next frame or the next field, the gray scale of the data supplied to each pixel is inverted so that By inverting and supplying the gray scale of the data, the low voltage AC drive can be performed and the polarity can be inverted for each pixel.

In the active matrix type liquid crystal display panel according to the second aspect of the present invention, pixel electrodes of odd columns or even columns are selected in each row in the first half of the horizontal period, and in the latter half of the one horizontal period. Pixel electrodes other than the pixel electrode selected in the first half of the one horizontal period are selected, the potential of the common electrode is inverted at an intermediate point of each horizontal period, and data supplied to each pixel in the next frame or the next field. In order to invert the grayscales of the data in the adjacent rows, the grayscales of the data supplied to the pixel electrodes in the odd-numbered columns and the grayscales of the data supplied to the pixel electrodes in the even-numbered columns are driven to be inverted in the adjacent rows. As a result, the low-voltage AC drive can be performed and the polarity can be inverted for each pixel.

When the active matrix type liquid crystal display panel according to the third aspect of the invention has the same structure as the second aspect of the invention, it is driven in the same manner as in the second aspect of the invention to perform low voltage AC driving, and It is possible to perform polarity inversion for each pixel.

On the other hand, due to the positional relationship of the defective switching element, if the structure cannot be formed in the same manner as in the case of the second aspect of the invention, that is, if the pixel electrodes in the odd and even columns cannot be completely divided and driven, For example, in the case where it is necessary to drive a part of the odd-numbered column and the even-numbered column at the same time, 1
The gate bus lines are sequentially driven every 1/2 horizontal period, and the potential of the common electrode is inverted every 1/2 horizontal period, so that the gradation of the data supplied to each pixel is inverted in the next frame or the next field. As described above, by supplying the data of the same polarity to all the data bus lines by inverting the grayscale every ½ horizontal period, the low voltage AC drive is performed and the polarity inversion is performed for each pixel except a part. It can be performed.

[0026]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The first embodiment of the present invention will now be described with reference to FIGS.
An active matrix type liquid crystal display panel of each of Examples 1 to 3 will be described. In the case of describing the driving method, the case of performing 8-gradation display will be described as an example.

First Embodiment FIG. 1 to FIG. 11 FIG. 1 is a TFT of a TFT substrate (a substrate on which a TFT is formed) which is a main part of an active matrix type liquid crystal display panel of the first embodiment of the present invention. a portion of the forming surface is a plan view schematically showing, in the figure, 17 ₁ to 17 _6, 18 _{1-18 6,} 1
9 _{1 to} 19 ₆ are pixel electrodes, 20 _{1 to} 20 ₆ , 21 _{1 to} 21 ₆ ,
22 _{1 to} 22 ₆ are TFTs, 23 ₁ to 23 ₄ are gate bus lines, 24 _{1 to} 24 ₆ are data bus lines, and G1 to G4 are gate pulses.

That is, in the active matrix type liquid crystal display panel of the first embodiment, the first gate bus line, the pixel electrode in the first row, the second gate bus line, the pixel electrode in the second row ... An n (where n = positive integer) gate bus line, an nth row pixel electrode, and an (n + 1) th gate bus line are arranged in order, and an odd column is provided in the ith row (where 1 ≦ i ≦ n). TFTs are provided so that the pixel electrodes of (1) are selected by the i-th gate bus line, and the pixel electrodes of even columns are selected by the (i + 1) th gate bus line.

FIG. 2 is a diagram showing an example of a driving method of the active matrix type liquid crystal display panel of the first embodiment, in which 25 is a gate driver for driving the gate bus lines 23 ₁ to 23 _j , and 26 is a gate driver. Is a data driver that drives the odd-numbered column data bus lines 24 _{1 to} 24 _2K-1 (hereinafter, referred to as upper data driver), and 27 is a data driver that drives the even-numbered column data bus lines 24 _{2 to} 24 _2k (hereinafter, lower Side data driver)).

Here, each of the upper data driver 26 and the lower data driver 27 has a plurality of driver ICs.
3 are arranged, for example, FIG. 3 is a block diagram showing a configuration of a driver IC that constitutes the upper data driver 26. In the figure, 28 is a shift register, 29 is a data register, 30 is a latch circuit, 31 is a selector, 3
Reference numeral 2 is an inverting / non-inverting circuit.

Further, SP is a start pulse, CL is a clock pulse, IS is an inversion / non-inversion instruction signal, LE is a latch pulse, and V1 to V8 are DC voltages having different voltage levels.

The inversion / non-inversion circuit 32 is controlled by the inversion / non-inversion instruction signal IS and outputs the input digital signals of RGB three colors with or without inversion.

The driver IC inputs the digitized video signals of the RGB three colors in the odd columns, inverts or does not invert the video signals, and after storing the data in the data register 29 pixel by pixel by the shift register 28. , The video signal stored in the data register 29 is latched in the latch circuit 30, the DC voltage corresponding to the video signal of each pixel latched by the latch circuit 30 is selected by the selector 31, and each of the selected pixels is selected. Is to be supplied to the pixel electrode via the data bus line.

FIG. 4 is a block diagram showing the configuration of the driver IC that constitutes the lower data driver 27.
In the figure, 33 is a shift register, 34 is a data register,
Reference numeral 35 is a latch circuit, 36 is a delay register forming a delay circuit having the same configuration as the latch circuit 35, 37 is a selector,
38 is an inverting / non-inverting circuit, LE1 is a latch pulse for the latch circuit 35, and LE2 is a latch pulse for the delay register 36.

The driver IC receives the digitized even-numbered columns of RGB three-color video signals, inverts or does not invert the video signals, and stores them in the data register 34 for each pixel by the shift register 33. , The video signal stored in the data register 34 is latched in the latch circuit 35, the data latched in the latch circuit 35 is transferred to the delay register 36, delayed by one horizontal period, and delayed by one horizontal period. The selector 37 selects a DC voltage corresponding to a video signal of a pixel, and the selected DC voltage for each pixel is applied to a pixel electrode via a data bus line.

FIG. 5 is a time chart showing the driving operation of an example of the driving method of the active matrix type liquid crystal display panel of the first embodiment, and FIGS. 6 to 10 are the active matrix of the first embodiment. FIG. 6 is a diagram for explaining a driving operation of an example of a driving method of the type liquid crystal display panel. Hereinafter, the driving operation will be described within this range.

First, in the first horizontal period, the potential of the common electrode is set to −2 [V], and the gate pulse G1 is applied to the gate bus line 23 ₁ of the first row. As a result, the odd-numbered TFTs 20 ₁ , 20 ₃ , 20 _{5 of} the first row are turned on, and as shown by hatching in FIG. 6, the pixel electrodes 17 ₁ , 17 ₃ of the odd-numbered row of the first row, 17 ₅ is selected.

In this case, the pixel electrodes 17 in the first row and the odd columns
Video signals D ₁₁ , D ₁₃ , and D _{15 in} the first row and odd-numbered columns are supplied to ₁ , 17 ₃ , and 17 ₅ from the upper data driver 26 in a state in which the gradation is not inverted. That is, in this case, positive polarity driving is performed.

Next, in the second horizontal period, the potential of the common electrode is set to 7 [V], and the gate pulse G2 is applied to the gate bus line 23 ₂ . As a result, the even-numbered TFTs 20 ₂ , 20 ₄ , and 20 _{6 in} the first row and the odd-numbered TFTs 21 ₁ , 21 ₃ , and 21 _{5 in} the second row are turned on, as shown by hatching in FIG. , The pixel electrode 1 in the first row and even column
7 ₂ , 17 ₄ , 17 ₆ and the pixel electrode 1 in the second row and the odd column
8 ₁ , 18 ₃ and 18 ₅ are selected.

In this case, the pixel electrodes 17 in the first row and even columns
₂ , 17 ₄ and 17 ₆ are supplied with the video signals D ₁₂ , D ₁₄ and D _{16 in} the even-numbered column of the first row from the lower data driver 27 in a state in which the gray levels are inverted and the second row. The upper data driver 2 is connected to the pixel electrodes 18 ₁ , 18 ₃ and 18 ₅ of the odd columns of
The video signals D ₂₁ , D ₂₃ , and D ₂₅ of the odd-numbered column of the second row from 6 are supplied in the state in which the gradation is inverted. That is, in this case, negative polarity driving is performed.

Next, in the third horizontal period, the potential of the common electrode is set to -2 [V], and the gate pulse G3 is applied to the gate bus line 23 ₃ . As a result, the TFTs 21 ₂ , 21 ₄ , 22 ₆ in the second row and the even columns and the TFTs 22 ₁ , 22 ₃ , 22 _{5 in} the third row and the odd columns are turned on, as shown by hatching in FIG. , The pixel electrode 1 in the second row and even column
8 ₂ , 18 ₄ and 18 ₆ and the pixel electrode 1 in the third row and the odd column
9 ₁ , 19 ₃ and 19 ₅ are selected.

In this case, the pixel electrodes 18 of the second row and even columns
₂ , 18 ₄ and 18 ₆ are supplied with the video signals D ₂₂ , D ₂₄ and D _{26 in} the even-numbered column of the second row from the lower data driver 27 in a state in which the gray scale is not inverted, and the second row Video signals D ₃₁ , D ₃₃ , and D _{35 in} the odd-numbered columns in the third row are supplied from the upper data driver 26 to the pixel electrodes 19 ₁ , 19 ₃ , and 19 ₅ in the odd-numbered columns without inverting the gray scales. That is, in this case, positive drive is performed.

Thereafter, the above operation is repeated to drive one field, and the relationship between the pixel electrode and the drive polarity is as shown by "positive" and "negative" in FIG. Therefore, in the next field, the gradation of the video signal is inverted and supplied to each pixel. As a result, the relationship between the pixel electrode and the driving polarity is as shown in FIG.

As described above, according to the first embodiment, the low voltage AC drive can be performed, and the polarity inversion is performed for each pixel so that the adjacent pixels have different drive polarities and display by flicker. It is possible to minimize the deterioration of quality.

FIG. 11 is a diagram showing another example of the driving method of the active matrix type liquid crystal display panel of the first embodiment of the present invention. In the figure, 39 is the upper data driver 2
6 is a data driver that does not have a delay register, and in this example, video signals of even columns are delayed by one horizontal period via the line memory 40 and supplied to the lower data driver 39. Also in the driving method,
The same effect as described above can be obtained.

Second Embodiment FIG. 12 to FIG. 23 FIG. 12 is a plan view schematically showing a part of the TFT formation surface of the TFT substrate which is the main part of the active matrix type liquid crystal display panel of the second embodiment of the present invention. In the figure, 41 ₁ ~
41 ₆ , 42 _{1 to} 42 ₆ , 43 ₁ to 43 ₆ are pixel electrodes, 44 ₁
To 44 _6, 45 ₁ to 45 _6, 46 ₁ to 46 ₆ TFT, 47 ₁
~ 47 ₃ , 48 ₁ ~ 48 ₃ are gate bus lines, G1A ~
G3A, G1B~G3B the gate pulse, 49 _{1-49 6}
Is a data bus line.

That is, in the active matrix type liquid crystal display panel of the second embodiment, two gate bus lines are provided in each row so as to sandwich the pixel electrode, and in each row, there are two pixel electrodes in odd columns. TFTs are provided so that one of the two gate bus lines can be selected, and the pixel electrode in the even-numbered column can be selected by the other gate bus line of the two gate bus lines. ..

FIG. 13 is a diagram showing an example of the driving method of the active matrix type liquid crystal display panel of the second embodiment, in which 50 is the gate bus lines 47 _{1 to} 47 _j , 4
8 ₁ gate driver for driving a to 48 _j, 51 the upper data driver for driving the data bus lines 49 ₁ to 49 _2K-1 of the odd-52 data bus lines 49 ₂ to the even columns
It is a lower data driver that drives _492k .

Here, each of the upper data driver 51 and the lower data driver 52 has a plurality of driver ICs.
FIG. 14 shows such a driver I
It is a block diagram which shows the structure of C. In the figure, 53 is a shift register, 54 is a data register, 55 is a latch circuit,
Reference numeral 56 is an inverting / non-inverting circuit, and 57 is a selector.

The driver IC inputs the digitized RGB three-color video signals of the odd-numbered columns or the even-numbered columns, stores them in the data register 54 for each pixel by the shift register 53, and then, the data register 54. The video signal stored in 54 is latched by the latch circuit 55, and the video signal of each pixel latched by the latch circuit 55 is inverted or not inverted via the inversion / non-inversion circuit 56 and transferred to the selector 57. The corresponding DC voltage is selected by the selector 57 and the selected DC voltage for each pixel is applied to the pixel electrode via the data bus line.

FIG. 15 is a time chart showing the driving operation of an example of the driving method of the active matrix type liquid crystal display panel of the second embodiment, and FIGS. 16 to 23 are the active matrix of the second embodiment. FIG. 6 is a diagram for explaining a driving operation of an example of a driving method of the type liquid crystal display panel. Hereinafter, the driving operation will be described within this range.

First, in the first half period of the first horizontal period, the potential of the common electrode is set to −2 [V], and the gate pulse G1A is applied to _one gate bus line 47 ₁ of the first row. As a result, the odd-numbered TFTs 44 ₁ in the first row,
44 _3, 44 ₅ is the ON, as shown by hatching in FIG. 16, the pixel electrode 41 ₁ of the odd-numbered column of the first row, 41 _3, 41
₅ is selected.

In this case, the pixel electrodes 41 in the first row and the odd columns
Video signals D ₁₁ , D ₁₃ , and D _{15 in} the first row and odd columns are supplied to ₁ , 41 ₃ , and 41 ₅ from the upper data driver 51 in a state in which the grayscale is not inverted. That is, in this case, positive polarity driving is performed.

Next, in the latter half of the first horizontal period, the potential of the common electrode is set to 7 [V] and the gate pulse G1B is applied to the other gate bus line 48 ₁ of the first row.
Applied to. As a result, the TFTs 44 in the first row and even columns
₂ , 44 ₄ , 44 ₆ are turned on, and as shown by hatching in FIG. 17, the pixel electrodes 41 ₂ , 41 ₄ , in the even-numbered columns of the first row,
41 ₆ is selected.

In this case, the pixel electrodes 41 in the first row and even columns
The video signals D ₁₂ , D ₁₄ and D _{16 in} the even-numbered columns of the first row are supplied from the lower data driver 52 to ₂ , 41 ₄ and 41 ₆ with their grayscales inverted. That is, in this case, negative polarity driving is performed.

Next, in the first half period of the second horizontal period, the gate pulse G2A is applied to the one gate bus line 47 of the second row while the potential of the common electrode is maintained at 7 [V].
Applied to ₂ . As a result, the TFTs 4 in the second row and the odd columns
5 ₁ , 45 ₃ , 45 ₅ are turned on, and as shown by hatching in FIG. 18, the pixel electrodes 42 ₁ , 4 in the odd columns of the second row 4
2 ₃ and 42 ₅ are selected.

In this case, the pixel electrodes 42 in the second row and the odd columns
Video signals D ₂₁ , D ₂₃ , and D _{25 in} the second row and odd columns are supplied to ₁ , 42 ₃ , and 42 ₅ from the upper data driver 51 in a state in which the gradation is inverted. That is, in this case, negative polarity driving is performed.

Next, in the latter half of the second horizontal period, the potential of the common electrode is set to -2 [V] and the gate pulse G2B is applied to the other gate bus line 48 of the second row.
Applied to ₂ . As a result, the TFTs 4 in the second row and even columns
5 _2, 45 _4, 45 ₆ is the ON, as shown by hatching in FIG. 19, the pixel electrode 42 ₂ of the even column of the second row, 4
2 ₄ and 42 ₆ are selected.

In this case, the pixel electrodes 42 in the second row and even columns
Video signals D ₂₂ , D ₂₄ , and D _{26 in} the second row and even columns are supplied from the lower data driver 52 to ₂ , 42 ₄ and 42 ₆ without inverting the gray scales. That is, in this case, positive polarity driving is performed.

Next, in the first half period of the third horizontal period, the potential of the common electrode is kept at -2 [V] and the gate pulse G3A is applied to the gate bus line 47 ₃ of the third row.
Applied to. As a result, the TFTs 46 in the third row and odd columns are
₁ , 46 ₃ and 46 ₅ are turned on, and as shown by hatching in FIG. 20, the pixel electrodes 43 ₁ and 43 ₃ in the odd rows of the third row,
43 ₅ is selected.

In this case, the pixel electrodes 43 of the third row and the odd columns
_1, 43 _3, 43 _5, the video signal D ₃₁ in the odd-numbered columns in the third row from the top data driver 51, D _33, D ₃₅ is supplied in a state which does not reverse the tone. That is, in this case, positive polarity driving is performed.

Next, in the latter half of the third horizontal period, the potential of the common electrode is set to 7 [V] and the gate pulse G3B is applied to the other gate bus line 48 ₃ of the third row.
Applied to. As a result, the TFTs 46 in the third row and even columns are
₂ , 46 ₄ , 46 ₆ are turned on, and as shown by hatching in FIG. 21, the pixel electrodes 43 ₂ , 43 ₄ , in the third row and even columns,
43 ₆ is selected.

In this case, the pixel electrodes 43 in the third row and even columns
Video signals D ₃₂ , D ₃₄ , and D _{36 in} the third row and even columns are supplied to ₂ , ₄ , 43, and 43 ₆ from the lower data driver 52 with their grayscales inverted. That is, in this case, negative polarity driving is performed.

Hereinafter, the above operation is repeated to drive one field, and the relationship between the pixel electrode and the drive polarity is shown by "positive" and "negative" in FIG. Therefore, in the next field, the gradation of the video signal is inverted and supplied to each pixel. As a result, the relationship between the pixel electrode and the driving polarity is as shown in FIG.

Thus, according to the second embodiment as well,
It is possible to perform low-voltage AC driving, perform polarity inversion for each pixel, and make adjacent pixels have different drive polarities, thereby minimizing deterioration in display quality due to flicker.

Third Embodiment FIG. 24 to FIG. 26 FIG. 24 is a plan view schematically showing a part of the TFT formation surface of the TFT substrate which is the main part of the active matrix type liquid crystal display panel of the third embodiment of the present invention. It is a view, in the figure, 58 ₁ ~
58 _6, 59 ₁ to 59 _6, 60 ₁ to 60 ₆ pixel electrode, 61 ₁
To 61 _6, 62 ₁ to 62 _6, 63 ₁ to 63 _6, 64 _1-6
4 ₆ , 65 _{1 to} 65 ₆ , 66 _{1 to} 66 ₆ are TFTs, 67 _{1 to} 6
7 _3, 68 _{1-68 3} gate bus line, 69 ₁ to 69 ₆
Is a data bus line.

The active matrix type liquid crystal display panel of the third embodiment is provided with two gate bus lines per row so as to sandwich the pixel electrode, and one or the other of the two gate bus lines per pixel electrode. Of the two TFTs which can be controlled by the gate bus line, and one of the two TFTs is made non-conductive by a laser or the like.

This is intended for the purpose of relieving a pixel which is not lit due to a defect of the TFT, and in the example of FIG. 24, the TFT 61 ₂ shown by a broken line,
61 ₄ , 61 ₆ , 62 ₁ , 62 ₃ , 62 ₅ , 63 ₄ , 63 ₆ ,
64 ₁ , 64 ₂ , 64 ₃ , 64 ₅ , 65 ₂ , 65 ₄ , 65 ₆ ,
66 ₁ , 66 ₃ and 66 ₅ are made non-conductive.

In the case of this example, for the second row, it is not possible to select the pixel electrodes in the odd-numbered columns and the pixel electrodes in the even-numbered columns separately, so drive them similarly to the case of the second embodiment. I can't.

Therefore, in this case, as in the case shown in FIG. 13, the gate driver 50 and the upper data driver 51 are provided.
And the lower data driver 52 are connected and driven as shown in a time chart in FIG. 25, for example.

That is, the gate pulses G1A, G1B, G2
Gate bus lines 67 ₁ , 68 ₁ , 67 in the order of A ...
₂ and the like, and for example, in the first half period of one horizontal period, the potential of the common electrode is set to −2 [V],
Both the upper data driver 51 and the lower data driver 52 output data that does not invert the gradation, and in the latter half period of one horizontal period, the potential of the common electrode is set to 7 [V], and the upper data driver 51 and the lower data driver 51 Data driver 5
It is possible to turn on all the pixels by outputting the data in which the gradations are inverted from both No. 2 and No. 2.

[0072] Also in this case, in the next field, by inverting the polarity of data supplied to each pixel, except for the portion of the pixel electrode 59 ₂ performs polarity reversal for each pixel, adjacent pixels Then make the drive polarities different,
It is possible to minimize the deterioration of display quality due to flicker.

Incidentally, in FIG. 26, in the third embodiment, T
_{FT61 2, 61 4, 61 6} , 62 1, 62 3, 62 5, 63
₂ , 63 ₄ , 63 ₆ , 64 ₁ , 64 ₃ , 64 ₅ , 65 ₂ , 6
5 ₄ , 65 ₆ , 66 ₁ , 66 ₃ , 66 ₅ are made non-conductive, and the second
It shows a case where the configuration is similar to that of the embodiment.

In this case, by driving in the same manner as in the case of the second embodiment, it is possible to perform low voltage AC driving, and also to perform polarity inversion for each pixel so that adjacent pixels have different drive polarities. Therefore, it is possible to minimize the deterioration of the display quality due to flicker.

[0075]

According to the present invention, low-voltage AC driving can be performed, and polarity inversion is performed for each pixel so that adjacent pixels have different drive polarities, thereby minimizing deterioration in display quality due to flicker. You can keep it to the limit.

However, according to the third invention, low-voltage AC driving can be performed as in the first and second inventions, but the polarity inversion for each pixel is Depending on the case, it can be performed except for a part of the pixel electrode portion, and within this range, it is possible to make the driving polarities different between the adjacent pixels and to suppress the deterioration of the display quality due to flicker to the minimum.

[Brief description of drawings]

FIG. 1 is a plan view schematically showing a part of a TFT formation surface of a TFT substrate which is a main part of an active matrix type liquid crystal display panel according to a first embodiment of the present invention.

FIG. 2 is a diagram showing an example of a driving method of the active matrix type liquid crystal display panel of the first embodiment of the present invention.

FIG. 3 is a block diagram showing a configuration of a driver IC that constitutes an upper data driver.

FIG. 4 is a block diagram showing a configuration of a driver IC that constitutes a lower data driver.

FIG. 5 is a time chart showing a driving operation of an example of a driving method of the active matrix type liquid crystal display panel of the first embodiment of the present invention.

FIG. 6 is a diagram for explaining a driving operation of an example of a driving method of the active matrix type liquid crystal display panel of the first embodiment of the present invention.

FIG. 7 is a diagram for explaining a driving operation of an example of a driving method of the active matrix type liquid crystal display panel of the first embodiment of the present invention.

FIG. 8 is a diagram for explaining a driving operation of an example of a driving method of the active matrix type liquid crystal display panel of the first embodiment of the present invention.

FIG. 9 is a diagram for explaining a driving operation of an example of the driving method of the active matrix type liquid crystal display panel of the first embodiment of the present invention.

FIG. 10 is a diagram for explaining a driving operation of an example of a driving method of the active matrix type liquid crystal display panel of the first embodiment of the present invention.

FIG. 11 is a diagram showing another example of the driving method of the active matrix type liquid crystal display panel of the first embodiment of the present invention.

FIG. 12 is a plan view schematically showing a part of a TFT formation surface of a TFT substrate which is a main part of an active matrix type liquid crystal display panel according to a second embodiment of the present invention.

FIG. 13 is a diagram showing an example of a method for driving an active matrix type liquid crystal display panel according to a second embodiment of the present invention.

FIG. 14 is a block diagram showing a configuration of a driver IC that constitutes an upper data driver and a lower data driver.

FIG. 15 is a time chart showing the driving operation of an example of the driving method of the active matrix type liquid crystal display panel of the second embodiment of the present invention.

FIG. 16 is a diagram for explaining a driving operation of an example of a driving method of the active matrix type liquid crystal display panel of the second embodiment of the present invention.

FIG. 17 is a diagram for explaining a driving operation of an example of the driving method of the active matrix type liquid crystal display panel of the second embodiment of the present invention.

FIG. 18 is a diagram for explaining a driving operation of an example of a driving method of the active matrix type liquid crystal display panel of the second embodiment of the present invention.

FIG. 19 is a diagram for explaining the driving operation of the example of the driving method of the active matrix type liquid crystal display panel of the second embodiment of the present invention.

FIG. 20 is a diagram for explaining a driving operation of an example of the driving method of the active matrix type liquid crystal display panel according to the second embodiment of the present invention.

FIG. 21 is a diagram for explaining the driving operation of the example of the driving method of the active matrix type liquid crystal display panel of the second embodiment of the present invention.

FIG. 22 is a diagram for explaining the driving operation of the example of the driving method of the active matrix type liquid crystal display panel of the second embodiment of the present invention.

FIG. 23 is a diagram for explaining a driving operation of an example of the driving method of the active matrix liquid crystal display panel of the second embodiment of the present invention.

FIG. 24 is a plan view schematically showing a part of a TFT formation surface of a TFT substrate which is a main part of an active matrix type liquid crystal display panel of Example 3 of the present invention.

FIG. 25 is a time chart showing the driving operation of the active matrix type liquid crystal display panel of the third embodiment of the present invention.

FIG. 26 shows the T of the TFT substrate in the third embodiment of the present invention, showing the case where the structure is the same as that of the second embodiment.
It is a top view which shows a part of FT formation surface schematically.

FIG. 27 is a partial perspective view showing a conventional active matrix liquid crystal display panel.

FIG. 28 is a block diagram showing a configuration of an example of a driver IC.

FIG. 29 is a diagram for explaining a low-voltage AC driving method.

[Explanation of symbols]

17 _{1-17 6} 18 _{1-18 6,} 19 ₁ to 19 ₆ pixel electrode _{20 1 ~20 6, 21 1 ~21} 6, 22 1 ~22 6 TFT 23 1 ~23 4 gate bus line 24 _{1-24 6} Data bus line

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location H01L 29/784

Claims (8)

[Claims] 1. A first gate bus line, a pixel electrode in a first row, a second gate bus line, a pixel electrode in a second row ...
Nth (where n = positive integer) gate bus line, nth
Pixel electrodes in rows and n + 1th gate bus lines are arranged in order, and in the i-th row (where 1 ≦ i ≦ n), the pixel electrodes in odd columns or even columns are selected by the i-th gate bus line. The active matrix type liquid crystal characterized in that the pixel electrodes other than the pixel electrode selected by the i-th gate bus line are provided with a switching element so as to be selected by the i + 1-th gate bus line. Display panel. 2. A method of driving an active matrix type liquid crystal display panel according to claim 1, wherein 1 is provided between data applied to pixel electrodes in odd columns and data applied to pixel electrodes in even columns. The delay time is an integral multiple of the horizontal period, the potential of the common electrode is inverted every horizontal period, and the gray scale of the data supplied to each pixel is inverted in the next frame or the next field. A method for driving an active matrix type liquid crystal display panel, characterized in that the gradation of data is inverted and supplied every horizontal period. 3. The method for driving an active matrix type liquid crystal display panel according to claim 2, wherein the delay time is obtained by providing a delay circuit inside a data driver for supplying data to the pixel electrodes. 4. The method of driving an active matrix type liquid crystal display panel according to claim 2, wherein the delay time is obtained by providing a delay circuit outside a data driver for supplying data to the pixel electrodes. 5. Two gate bus lines per row are provided so as to sandwich a pixel electrode, and in each row, the pixel electrodes in odd columns or even columns have one gate bus line of the two gate bus lines. Pixel electrodes other than the pixel electrodes selected by the line and selected by the one gate bus line are provided with a switching element so that the other gate bus line of the two gate bus lines is selected. An active matrix type liquid crystal display panel characterized by being provided. 6. The method for driving an active matrix liquid crystal display panel according to claim 5, wherein in each row, in the first half period of one horizontal period, pixel electrodes in odd columns or even columns are selected and one horizontal period is selected. In the latter half of the period, a pixel electrode other than the pixel electrode selected in the first half of the one horizontal period is selected, the potential of the common electrode is inverted at an intermediate point of each horizontal period, and in the next frame or the next field, In order that the grayscale of the data supplied to each pixel is inverted, the grayscale of the data supplied to the pixel electrodes in the odd columns and the grayscale of the data supplied to the pixel electrodes in the even columns are in an inverted relationship in the adjacent rows. A method for driving an active matrix type liquid crystal display panel, characterized in that the driving is performed as described in 1. 7. Two gate bus lines per row are provided so as to sandwich the pixel electrode, and two pixel bus lines can be controlled by one or the other of the two gate bus lines per pixel electrode. An active-matrix liquid crystal display panel, characterized in that a switching element is provided and one of the switching elements is made non-conductive. 8. A method of driving an active matrix type liquid crystal display panel according to claim 7, wherein the gate bus lines are sequentially driven every 1/2 horizontal period, and the potential of the common electrode is reduced every 1/2 horizontal period. In the next frame or the next field, the data having the same polarity is inverted in every data bus line every half horizontal period so that the gray level of the data supplied to each pixel is inverted. A method for driving an active matrix liquid crystal display panel, which is characterized in that the liquid crystal display panel is supplied as a light source.