JP3148925B2 - 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 liquid crystal display device useful as a display device for video equipment such as a television receiver and information equipment such as a computer.

[0002]

2. Description of the Related Art In recent years, a liquid crystal display device has been widely used as a display device of a video device such as a television receiver and an information device such as a computer. The challenge is to make the picture frame.

Hereinafter, a conventional liquid crystal display device will be described with reference to the drawings. FIG. 4 is a plan view showing a configuration of a conventional liquid crystal display device. In the figure, 1 is a signal wiring group,
2 is a signal electrode drive I for driving a signal electrode (not shown)
C, 3 are scanning electrode driving ICs for driving scanning electrodes (not shown), 4 is a flexible wiring board, and 5 is a liquid crystal panel.

The operation of the above configuration will be described. In the figure, a signal wiring group 1, a signal electrode driving IC 2, a scanning electrode driving IC 3, and a flexible wiring board 4 are installed and connected on a glass at a peripheral portion of a liquid crystal panel 5 (hereinafter, simply referred to as the liquid crystal panel 5). ing. From the flexible wiring board 4, a driving signal such as a video signal and a control signal and a power supply are transmitted to a signal wiring group 1 installed on the liquid crystal panel 5.
To the signal electrode drive IC2 and the scan electrode drive IC3. The signal supplied to the signal electrode drive IC 2 is subjected to signal processing in the signal electrode drive IC 2 to drive the signal electrodes,
The signal supplied to the scanning electrode driving IC 3 is processed in the scanning electrode driving IC 3 to drive the scanning electrodes and display an image on the liquid crystal display device.

FIG. 5 shows the signal electrode driving IC 2 shown in FIG.
FIG. 2 is an enlarged plan view showing the vicinity of the device. Note that the same components as those in FIG. 4 are denoted by the same reference numerals, and detailed description is omitted. In the figure, reference numeral 6 denotes a signal input terminal of the signal electrode drive IC 2, 7 denotes a signal output terminal of the signal electrode drive IC 2, 8
Denotes a signal electrode of the liquid crystal panel 5, 9 denotes a sample and hold circuit group of the signal electrode drive IC 2, 10 denotes an output amplifier circuit group of the signal electrode drive IC 2, and 11 denotes a logic circuit group of the signal electrode drive IC 2.

Conventionally, as shown in FIG. 5, a video signal, a control signal, a power supply, and the like input from a flexible wiring board 4 are transmitted through signal wiring groups 1 provided on a liquid crystal panel 5 to respective signal electrode driving ICs 2. The signal is input to a signal input terminal 6 corresponding to the signal. At this time, the signal wiring group 1 is arranged so that the individual signal wirings do not cross each other on the liquid crystal panel 5.
It is designed to meander on the lower surface side or outside of the signal electrode drive IC 2. If the individual signal lines intersect each other on the liquid crystal panel 5, a problem such as a short circuit occurs at the intersecting portion when static electricity or the like enters the signal line group 1. Therefore, it is solved by this method.

A control signal among the signals input to the signal input terminal 6 via the signal wiring group 1 is a signal electrode driving IC 2
And the signal electrode driving IC 2
And a control signal for controlling the sample-and-hold circuit group 9 and the output amplifier circuit group 10. A video signal among the signals input to the signal input terminal 6 via the signal wiring group 1 is directly sent to the sample and hold circuit group 9 of the signal electrode driving IC 2. This video signal is sampled and held by the sample and hold circuit group 9 by the control signal generated by the logic circuit group 11. The video signal held by the sample and hold circuit group 9 is output to the output amplifier circuit group 1
The signal is amplified by 0, sent to the signal output terminal 7, sent to the signal electrode 8 of the liquid crystal panel 5 connected to the signal output terminal 7, and displayed on the liquid crystal panel 5.

At present, the signal electrode driving IC 2 is further downsized to reduce the cost of the liquid crystal display device, and the frame is being narrowed down to make the liquid crystal panel 5 compact.

[0009]

In such a conventional liquid crystal display device, in order to reduce the cost, the signal electrode driving I / O is required.
Although the frame is becoming narrower in order to further reduce the size of C2 and to make the liquid crystal panel 5 more compact, the current situation is that the wiring resistance of the signal wiring group 1 cannot be significantly reduced. It is necessary to maintain the current wiring structure from the viewpoint of securing the stability of signal transmission, and the space saving of the signal wiring group 1 cannot be expected. Therefore, the miniaturization of the signal electrode driving IC 2 is intended to simultaneously achieve the cost reduction and the narrow frame.

Hereinafter, the configuration of the signal wiring group 1 is maintained as it is,
The problem when the signal electrode driving IC 2 is downsized will be described with reference to the drawings.

FIG. 6 is essentially the same as FIG.
The size of the signal electrode driving IC 2 is reduced in the short side direction, and the crosstalk unit 12 to which the present invention is directed is added.

As described above, the signal wiring group 1 is devised so as to meander on the lower surface side or outside of the signal electrode driving IC 2 so that the individual signal wirings do not cross each other on the liquid crystal panel 5. However, the current wiring structure of the signal wiring group 1 is maintained, and the cost reduction of the liquid crystal display device and the narrow frame for achieving the compact liquid crystal panel 5 are realized by the downsizing of the signal electrode driving IC 2. If this is attempted, the size in the short side direction of the signal electrode drive IC 2 must be smaller than that shown in FIG. 5 as shown in FIG.
In this case, the liquid crystal panel 5 on the lower surface side of the signal electrode driving IC 2
Signal wiring group 1 configured above and having a meandering structure
The crosstalk section 12 is more likely to be generated between the video signal line in the inside and the sample and hold circuit group 9 of the signal electrode drive IC 2, and the image sampled and held by the sample and hold circuit group 9 of the signal electrode drive IC 2 The signal potential is interfered by the crosstalk unit 12. This interference causes a deviation in the video signal sent to the signal electrode 8 of the liquid crystal panel 5, causing a problem that an image to be displayed on the liquid crystal panel 5 cannot be displayed.

FIG. 7 is an enlarged plan view showing the crosstalk section 12 shown in FIG. In the figure, 13 is a video signal line in the signal wiring group 1, 14 is an output amplifier circuit, and 15 is a sample and hold circuit. Note that reference numeral 11 denotes the above-described logic circuit group. The signal electrode drive IC 2 includes an output amplifier circuit 14 and a sample hold circuit 15 corresponding to each of the signal output terminals 7 to which each signal electrode 8 of the liquid crystal panel 5 is connected. The output amplifier circuit 14 and the sample-and-hold circuit 15 are individually independent, sample and hold a video signal individually, amplify the signal, and transmit it to each signal electrode 8 of the liquid crystal panel 5. The logic circuit group 11 controls the output amplifier circuit 14 and the sample and hold circuit 15.

If the size of the signal electrode driving IC 2 in the short side direction is reduced in order to reduce the cost and the frame width of the liquid crystal panel 5, the video signal lines formed on the liquid crystal panel 5 on the lower surface side of the signal electrode driving IC 2 are reduced. Crosstalk occurs between the logic circuit group 13 and the output amplifier circuit 14, the sample-and-hold circuit 15, and the logic circuit group 11 of the signal electrode drive IC 2. The output amplifier circuit 14 amplifies and outputs the sampled and held potential by the voltage follower amplifier circuit of the voltage gain. Therefore, as long as there is no change in the input potential before the amplification, the output signal is generated by the crosstalk of the video signal line 13. Few fluctuations. In the logic circuit group 11, since the signal being handled is a digital control signal for turning on / off, there is no influence of crosstalk of the video signal line 13.

However, the sample hold circuit 15 is affected by the crosstalk of the video signal line 13 for the following reason. Conventionally, the sample-and-hold circuit 15 is composed of a capacitor of about several pf or the like, and holds a sampled video signal by accumulating charges in this capacitor. Since the electric charge held by the capacitor of about several pf is weak, it is very easily affected by the constantly changing fluctuation of the video signal line 13 due to crosstalk with the video signal line 13.

Therefore, the crosstalk between the sample and hold circuit 15 and the video signal line 13 causes a deviation in the video signal sent to the signal electrode 8 of the liquid crystal panel 5, that is, the potential held by the sample and hold circuit 15 As a result, unevenness on the liquid crystal panel 5 occurs on the vertical line, and the image to be displayed cannot be displayed.

The present invention solves the above-mentioned problems, and comprises a video signal line 13 and a signal electrode driving IC in a signal wiring group 1.
2 reduces the crosstalk between the sample and hold circuit 15 and the current wiring structure of the signal wiring group 1, reduces the cost of the liquid crystal display device, and reduces the cost of the liquid crystal panel 5.
It is an object of the present invention to provide a liquid crystal display device which does not affect the display quality even if the signal electrode driving IC 2 is downsized and the frame is narrowed for the purpose of downsizing.

[0018]

According to a first aspect of the present invention, a video signal line is provided at a portion where a video signal line and a sample-and-hold circuit group of video signals in a signal electrode driving IC cross three-dimensionally. This is a liquid crystal display device in which a gap in the arrangement of the sample hold circuits in the sample hold circuit group is passed.

Thus, the crosstalk between the video signal line and the sample-and-hold circuit is reduced, and the signal electrode driving IC is reduced in size and the cost is reduced and the frame is narrowed while maintaining the current wiring structure of the signal wiring group. This can be realized at the same time, and an image to be displayed on the liquid crystal panel can be displayed without any problem.

According to a second aspect of the present invention, in a portion where a video signal line and a sample-and-hold circuit group of a video signal in a signal electrode driving IC three-dimensionally intersect, the video signal line is connected to the sample signal. This is a liquid crystal display device in which only a sample and hold circuit for sampling and holding in a hold circuit group intersects.

As a result, the crosstalk between the video signal line and the sample-and-hold circuit is reduced, and the wiring structure of the signal wiring group is maintained. This can be realized at the same time, and an image to be displayed on the liquid crystal panel can be displayed without any problem.

According to a third aspect of the present invention, in a portion where a video signal line and a sample-and-hold circuit group of video signals in a signal electrode driving IC are three-dimensionally intersected, the video signal line is sampled by the video signal line. This is a liquid crystal display device that intersects only with a sample and hold circuit for sampling and holding in a group of hold circuits and passes through a gap in an array of sample and hold circuits for other video signals.

As a result, the crosstalk between the video signal line and the sample-and-hold circuit is reduced without making the video signal line thin, and the signal electrode driving IC is downsized while maintaining the current wiring structure of the signal wiring group. Low cost and narrow frame can be realized at the same time, and an image to be displayed on the liquid crystal panel can be displayed without any problem.

[0024]

In the present invention according to the first aspect, individual sample and hold circuits of a sample and hold circuit group in a signal electrode driving IC are arranged at an interval from each other, and a sample and hold circuit and an adjacent sample and hold circuit are arranged. A video signal line is passed through a gap between the circuit and the circuit so that the video signal line does not face the sample and hold circuit.

In the present invention according to claim 2, the video signal line intersects only with a sample and hold circuit which samples and holds the video signal of the video signal line.

According to the third aspect of the present invention, the video signal line intersects only with a sample / hold circuit which samples and holds the video signal of the video signal line, and a gap in the arrangement of other video signal sample / hold circuits. To increase the line width of the video signal line.

Hereinafter, embodiments will be described.

[0028]

【Example】

(Embodiment 1) Hereinafter, Embodiment 1 of the liquid crystal display device of the present invention will be described with reference to the drawings. This embodiment relates to claim 1.

FIG. 1 is a plan view showing the structure of this embodiment. The same components as those in the conventional example shown in FIGS. 4 to 7 are given the same reference numerals, and detailed description is omitted. This embodiment is different from the conventional example in that the video signal line 13 is connected to the portion of the sample and hold circuit group 9 where the sample and hold circuit 15 is not provided, that is, the sample and hold circuit 1
5 is arranged so as to pass through the gap.

The operation of the above configuration will be described. The signal electrode drive IC 2 includes an output amplifier circuit 14 and a sample hold circuit 15 corresponding to the terminals of each signal electrode 8 of the liquid crystal panel 5, and the output amplifier circuit 14 and the sample hold circuit 15 are individually independent, The video signal is individually sampled and held, amplified, and transmitted to each signal electrode 8 of the liquid crystal panel 5. Logic circuit group 1
1 controls the output amplifier circuit 14 and the sample hold circuit 15.

In this embodiment, as shown in FIG. 1, in the conventional example, at the portion where the crosstalk portion 12 between the video signal line 13 and the sample-hold circuit group 9 occurs,
A portion where the sample and hold circuit 15 corresponding to each output is not configured, that is, one sample and hold circuit 1
5 and the video signal line 13 is passed through a gap between the sample / hold circuit 15 and the adjacent sample / hold circuit 15, so that the crosstalk section 1 between the sample / hold circuit 15 and the video signal line 13
2 can be eliminated, and in the sample-and-hold circuit 15 composed of a capacitor of about several pf, a weak signal held by this capacitor is hardly affected by crosstalk from the video signal line 13. This solves the problem that an image to be displayed on the liquid crystal panel 5 cannot be displayed due to the crosstalk between the sample hold circuit 15 and the image signal line 13. Even if the signal electrode driving IC 2 is reduced in size, a liquid crystal with good display quality can be solved. A display device can be realized.

(Embodiment 2) Hereinafter, Embodiment 2 of the liquid crystal display device of the present invention will be described with reference to the drawings. This embodiment relates to claims 2 and 3.

FIGS. 2 and 3 are plan views showing the structure of this embodiment. 2 and 3, reference numeral 13R denotes a red video signal line in the video signal line 13, 14R denotes a red output amplifier circuit that outputs a video signal to a red signal electrode, and 14G denotes a green that outputs a video signal to a green signal electrode. Output amplifier circuit, 1
4B is a blue output amplifier circuit for outputting a video signal to a blue signal electrode, 15R is a red sample and hold circuit for sampling and holding a red video signal, 15G is a green sample and hold circuit for sampling and holding a green video signal, 15B Is a blue sample and hold circuit that samples and holds the blue video signal,
Reference numeral 11 denotes a logic circuit group.

The operation of the above configuration will be described. In FIG. 2, the signal electrode driving IC is a red
A red output amplifier circuit 14R, a green output amplifier circuit 14G, and a blue output amplifier circuit 14B corresponding to the terminals of the green and blue signal electrodes, and a red sample-hold circuit 15R and a green sample-hold circuit corresponding to each color output amplifier circuit. 15G, and a blue sample hold circuit 15B. The output amplifier circuit and the sample-and-hold circuit corresponding to each color are individually independent, and different types of video signals, that is, red, green, and blue signals are individually sampled and held, amplified, and amplified on the liquid crystal panel 5.
Is transmitted to the signal electrode of each color. Logic circuit group 1
1 controls each output amplifier circuit and the sample hold circuit.

As described above, the signal electrode driving IC 2
If the size in the short side direction is made smaller, the red video signal line 13R formed on the liquid crystal panel 5 on the lower surface side of the signal electrode driving IC 2, the output amplifier circuit and the sample hold circuit corresponding to each color of the signal electrode driving IC 2 , And a logic circuit group 11, a crosstalk section 12 is generated.

In this embodiment, as shown in FIG. 2, at a portion where the crosstalk section 12 occurs between the red video signal line 13R and the sample and hold circuit group 9, a red sample and hold circuit corresponding to a red output is provided. By using a configuration in which the red video signal line 13R passes only through the portion where the 15R is configured, the green sample-hold circuit 15G and the blue sample-hold circuit 15B, which are sample-hold circuits corresponding to other colors, Since the arrangement is not adjacent to the red video signal line 13R as shown in the first embodiment,
Crosstalk can be further reduced, and the weak signal held by the sample-and-hold circuit of another color has a structure that is hardly affected by crosstalk with the red video signal line 13R. The red sample hold circuit 15R has no effect because it is a video signal corresponding to itself.

Therefore, it is possible to solve the problem that an image to be displayed on the liquid crystal panel 5 cannot be displayed due to crosstalk of different color signals. Even if the size of the signal electrode driving IC is reduced, the display quality is affected. A liquid crystal display device that does not appear can be realized.

Embodiment 3 Hereinafter, a third embodiment of the liquid crystal display device of the present invention will be described with reference to the drawings. This embodiment relates to claim 3.

FIG. 3 is a plan view showing the structure of this embodiment. Note that the same components as those in FIG. 2 are denoted by the same reference numerals, and detailed description is omitted. 2. The configuration of the second embodiment shown in FIG.
That is, in a portion where the crosstalk section 12 occurs between the red video signal line 13R and the sample hold circuit group, the red sample hold circuit 15 corresponding to the red output is provided.
In a configuration in which the red video signal line 13R is passed only through the portion where R is formed, the line width of the red video signal line 13R is reduced, so that the wiring resistance is increased, and the red video signal line 13R is sufficiently transmitted. It may not be possible.

In the present embodiment, as shown in FIG. 3, the gap between the green sample-hold circuit 15G and the blue sample-hold circuit 15B, which are sample-hold circuits corresponding to other colors, also includes the red video signal line 13R. The crosstalk between the red video signal line 13R, the green sample-and-hold circuit 15G, and the blue sample-and-hold circuit 15B is reduced, and the weak signal held by the other color sample-and-hold circuit is replaced with the red video signal. The structure is hardly affected by the line 13R. Also,
The red sample-and-hold circuit 15R has little effect because it is a video signal corresponding to itself.

Therefore, while the line width of the video signal line is not reduced, that is, the resistance of the video signal line is not increased, the video to be displayed on the liquid crystal panel is affected by the crosstalk from the different color signals. It is possible to solve the problem that the liquid crystal display device cannot be used, and to realize a liquid crystal display device that does not affect display quality even if the signal electrode driving IC is reduced in size.

In the above description, the red video signal line has been described. However, this video signal line may be video signal lines of other colors besides blue and green.
Although the case of displaying three colors of green and blue has been described, the display color may be two colors or three or more colors.

The configuration shown in the embodiment of the present invention is an example, and an active matrix type liquid crystal panel, a simple matrix type liquid crystal panel, or a liquid crystal display device using another matrix type display panel may be used. Needless to say.

[0044]

As is apparent from the above description, according to the present invention, the liquid crystal panel is provided by arranging the video signal line and the sample / hold circuit of the video signal in the signal electrode driving IC so that no crosstalk occurs. Signal electrode drive IC on top
Electrode driving IC so that crosstalk does not occur while maintaining the conventional wiring configuration in which the signal wiring group and the signal wiring group are arranged.
Can be reduced in size, the frame of the liquid crystal panel can be narrowed, and the cost of the liquid crystal display device can be reduced at the same time, and an image can be displayed normally.

[Brief description of the drawings]

FIG. 1 is a plan view showing a configuration of a liquid crystal display device according to a first embodiment of the present invention.

FIG. 2 is a plan view illustrating a configuration of a liquid crystal display device according to a second embodiment of the present invention.

FIG. 3 is a plan view illustrating a configuration of a liquid crystal display device according to a third embodiment of the present invention.

FIG. 4 is a plan view showing a configuration of a conventional liquid crystal display device.

FIG. 5 shows a signal electrode drive I in the conventional liquid crystal display device.
Plan view showing C and its vicinity

FIG. 6 shows a signal electrode drive I in the conventional liquid crystal display device.
FIG. 4 is a plan view showing a signal electrode driving IC when the short side of C is reduced and its vicinity.

FIG. 7 shows a signal electrode drive I in the conventional liquid crystal display device.
FIG. 2 is an enlarged plan view showing a crosstalk portion between a sample hold circuit in C and a video signal line;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Signal wiring group 2 Signal electrode drive IC 3 Scan electrode drive IC 4 Flexible wiring board 5 Liquid crystal panel 6 Signal input terminal 7 Signal output terminal 8 Signal electrode 9 Sample hold circuit group 10 Output amplifier circuit group 11 Logic circuit group 12 Crosstalk part 13 Video Signal Line 13R Red Video Signal Line 14 Output Amplifier Circuit 14R Red Output Amplifier Circuit 14G Green Output Amplifier Circuit 14B Blue Output Amplifier Circuit 15 Sample Hold Circuit 15R Red Sample Hold Circuit 15G Green Sample Hold Circuit 15B Blue Sample Hold Circuit

Continuation of the front page (56) References JP-A-6-332000 (JP, A) JP-A-9-325368 (JP, A) JP-A-60-122923 (JP, U) JP-A-3-37494 (JP) , U) (58) Fields investigated (Int. Cl. ⁷ , DB name) G02F 1/1345 G02F 1/136 G02F 1/1343 G02F 1/133 G09G 3/36

Claims (3)

(57) [Claims] A liquid crystal panel on which signal electrodes and scanning electrodes are formed in a matrix; a signal electrode driving IC for driving the signal electrodes; a scanning electrode driving IC for driving the scanning electrodes; And a signal line group including at least one type of video signal line for transmitting a signal to the IC and the scan electrode drive IC.
And the scan electrode driving IC and the signal wiring group are set on the glass at the peripheral portion of the liquid crystal panel, and the video signal sample and hold circuit group and the signal wiring group provided in the signal electrode driving IC are three-dimensional. In the liquid crystal display device having a portion that intersects with the sample and hold circuit group, the video signal line of the signal line group is passed through the gap of the arrangement of the sample and hold circuit in the sample and hold circuit group, so that the video signal line A liquid crystal display device that does not face any of them. 2. A liquid crystal panel in which signal electrodes and scan electrodes are formed in a matrix, a signal electrode drive IC for driving the signal electrodes, a scan electrode drive IC for driving the scan electrodes, and the signal electrode drive. And a signal line group including at least two types of video signal lines for transmitting signals to the IC and the scan electrode drive IC.
And the signal electrode driving IC and the signal wiring group are set on the glass at the peripheral portion of the liquid crystal panel, and the video signal sample and hold circuit group and the signal wiring group provided in the signal electrode driving IC are three-dimensional. In a liquid crystal display device having a portion that intersects with the video signal line, the video signal line passes only through a sample and hold circuit that samples and holds the video signal of the video signal line, so that the video signal line A liquid crystal display device which is opposed only to a sample and hold circuit for a line video signal. 3. A liquid crystal display device in which a signal wiring group includes at least three or more types of video signal lines and a video signal to be sampled and held for each scanning electrode is switched between two or more types. 3. A video signal line intersecting with the video signal line only intersects with a sample-and-hold circuit for sampling and holding the video signal of the video signal line, and passes through a gap in an array of sample-and-hold circuits for other video signals. Liquid crystal display device.