JPH07230074A - Liquid crystal display device - Google Patents

Abstract

PURPOSE:To provide the liquid crystal display device which has high contrast and excellent visual field characteristics at low cost without transparent electrodes by placing the device in operation while the long-axis direction of liquid crystal molecules of a liquid crystal composition material is held almost in parallel to a substrate surface according to electric field intensity based upon the potential difference between pixel electrodes and signal wirings. CONSTITUTION:Linear electrodes 201 and 2092 are formed inside a couple of transparent substrates 203, orientation control films 203 are formed thereupon by coating and oriented, and the liquid crystal composition is sandwiched between them. Rod type liquid crystal molecules 205 are oriented having slight angles to the length direction of the striped electrodes 201 and 202. Then when an electric field 207 is applied, the liquid crystal molecules 205 change their directions to the electric field direction. The polarized light transmission axis of a polarizing plate 206 is arranged at a specific angle 209, and then the light transmittance can be changed by voltage application. In display mode, the long axes of the liquid crystal molecules 205 are always nearly parallel to the substrates 203 and never rise, and then no visual angle dependency is obtained, thereby improving the visual angle characteristics.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an active matrix type liquid crystal display device having good display characteristics, good mass productivity and low cost.

[0002]

2. Description of the Related Art In a conventional active matrix type liquid crystal display device, transparent electrodes, which are formed on the interface between two substrates and face each other, are used as electrodes for driving a liquid crystal layer. This is because a twisted nematic display method is adopted, which operates by making the direction of the electric field applied to the liquid crystal substantially perpendicular to the substrate interface. On the other hand, a method of making the direction of the electric field applied to the liquid crystal substantially parallel to the substrate interface has been proposed, for example, in Japanese Patent Laid-Open No. 56-91277.

[0003]

However, in the prior art using the twisted nematic display system, I
In order to form a transparent electrode typified by TO, it is necessary to use vacuum-type manufacturing equipment such as sputtering, and the equipment cost is huge. Also, the use of vacuum-based manufacturing equipment causes a reduction in throughput, which significantly increases manufacturing costs. Further, in general, the transparent electrode has irregularities of about several tens of nm on its surface, which makes it difficult to process a fine active element such as a thin film transistor. In addition, the protrusions of the transparent electrode often come off and mix into other parts such as electrodes, causing dot-shaped or line-shaped display defects,
The yield was remarkably reduced. For these reasons, it has been impossible to stably provide a low-cost liquid crystal display device that meets market needs. Moreover, in the conventional technology,
There were many problems in terms of image quality. In particular, the luminance changes significantly when the viewing angle direction is changed, making it difficult to display halftone.

Further, in the method of applying the electric field in the direction substantially parallel to the substrate interface to the liquid crystal, it is not necessary to use ITO,
In the conventional known technology, since a common electrode is required, the probability of short circuit at the wiring intersection is increased and the yield is reduced. Further, the common electrode occupies a part of the pixel portion, thus lowering the aperture ratio. Further, the method of sharing the common electrode with the scanning wiring or the signal wiring has a problem in that the liquid crystal cannot be AC-driven or the driving method is complicated and the circuit scale of the driving circuit increases.

An object of the present invention is, firstly, to provide a low-cost active matrix type liquid crystal display device which has a high contrast without a transparent electrode and which can be mass-produced with a low-cost facility and a high yield. Secondly, it is to provide an active matrix type liquid crystal display device having good viewing angle characteristics and easy multi-gradation display. Third, to provide an active matrix type liquid crystal display device having a high aperture ratio and being bright. Fourthly, the driving method is simple, the signal voltage can be further lowered, the power consumption is low, the withstand voltage is low, and the cost is low.
An object is to provide an active matrix liquid crystal display device that can use SI.

[0006]

In order to achieve the above object, the present invention comprises, as a first device, a pair of substrates and a liquid crystal composition layer sandwiched between the substrates, and one of the substrates is provided on the substrate. A plurality of scanning wirings and signal wirings are arranged in a matrix, and a region on the substrate is divided into a plurality of pixel regions,
In each pixel region, an active element and a capacitive element are arranged in a state of being electrically connected to the liquid crystal composition layer, and the active element and the capacitive element are connected to any of the wirings to form a liquid crystal drive circuit. In the liquid crystal display device in which each scanning wiring is connected to the scanning signal generating means and each signal wiring is connected to the video signal generating means, the liquid crystal molecules of the liquid crystal composition layer are connected to the active element and the pixel electrode connected to the pixel electrode. A liquid crystal display device is constructed which operates in such a manner that the long axis direction of liquid crystal molecules is kept substantially parallel to the substrate surface according to the electric field strength according to the potential difference of the signal wiring.

A second device including the first device is characterized in that the capacitive element is composed of a pixel electrode and a signal wiring.

In a third device including the first device and the second device, the active element is a transistor element.

As a fourth device including the first device and the second device, the active element is a diode element.

A fifth device is composed of a pair of substrates and a liquid crystal composition layer sandwiched between the substrates, and a plurality of scanning wirings and signal wirings are arranged in a matrix on one substrate,
A region on the substrate is divided into a plurality of pixel regions, and in each pixel region, a transistor element and a capacitor element are arranged in a state of being electrically connected to a liquid crystal composition layer, and the transistor element and the capacitor element are disposed. Is connected to one of the above wirings to form a liquid crystal drive circuit, each scanning wiring is connected to scanning signal generating means, and each signal wiring is connected to video signal generating means. The means includes a voltage for turning on the transistor element,
It is characterized in that it has means for generating a voltage for turning off the transistor element and a voltage to be inputted to the pixel electrode. A sixth device including the fifth device is characterized in that the scanning signal generating means has means for generating two or more values of a voltage input to the pixel electrode.

[0011]

Next, the operation of the present invention will be described with reference to FIG.

16 (a) and 16 (b) are side sectional views showing the operation of the liquid crystal in the liquid crystal panel of the present invention.
Represents the front view. In FIG. 16, the active element is omitted. Further, in the present invention, a plurality of pixels are formed by forming a striped electrode, but only one pixel portion is shown here. The cross section of the cell when no voltage is applied is shown in FIG.
A front view at that time is shown in FIG. Linear electrodes 201 and 202 are formed on the inner side of a pair of transparent substrates 203, and an alignment control film 204 is applied and aligned on the linear electrodes 201 and 202. A liquid crystal composition is sandwiched between them. The rod-shaped liquid crystal molecule 205 has a slight angle with respect to the longitudinal direction of the striped electrode when no electric field is applied, that is, an angle formed by the liquid crystal molecule major axis (optical axis) direction near the interface with respect to 45 ° ≦ | | <90 degrees. The alignment direction of liquid crystal molecules on the upper and lower interfaces will be described here by taking parallel as an example. The dielectric anisotropy of the liquid crystal composition is assumed to be positive. Next, when an electric field 207 is applied, as shown in FIG.
As shown in (d), the liquid crystal molecules change their directions in the direction of the electric field. By arranging the polarization transmission axis of the polarizing plate 206 at a predetermined angle 209, the light transmittance can be changed by applying an electric field. As described above, according to the present invention, it is possible to provide a display with contrast even without the transparent electrode.

The specific structure for imparting contrast is as follows.
A mode using a state in which the liquid crystal molecule orientations on the upper and lower substrates are substantially parallel (because the interference color due to the birefringence phase difference is used,
This is called a birefringence mode) and a mode utilizing a state in which the alignment directions of liquid crystal molecules on the upper and lower substrates intersect and the molecular arrangement in the cell is twisted (a rotation plane in which the plane of polarization rotates in the liquid crystal composition layer). Because it utilizes the nature, it is called the optical rotation mode here). In the birefringence mode, the direction of the molecular long axis (optical axis) is changed in the plane while the direction of the molecular long axis (optical axis) is almost parallel to the substrate interface by applying a voltage, and the angle formed by the axis of the polarizing plate set to a predetermined angle is changed. Change the transmittance. Similarly, even in the optical rotation mode, only the orientation of the molecular long axis direction is changed by applying a voltage,
In this case, the change in optical activity due to the unravel of the streak is used. Further, in the display mode of the present invention, the long axis of the liquid crystal molecule is always substantially parallel to the substrate and does not rise, and therefore the change in brightness when the viewing angle direction is changed is small, so there is no viewing angle dependency, The viewing angle characteristics are significantly improved. In this display mode, the dark state is not obtained by making the birefringence phase difference almost zero by applying a voltage as in the conventional case, but the angle formed by the long axis of the liquid crystal molecule and the axis of the polarizing plate (absorption or transmission axis) It changes and is fundamentally different. In the case of raising the liquid crystal molecule long axis perpendicular to the substrate interface as in the conventional TN type, the viewing angle direction in which the birefringence phase difference becomes 0 is only the front direction, that is, the direction perpendicular to the substrate interface, and even if it is slightly inclined. Then, a birefringence phase difference appears. In the normally open type, light leaks, causing a decrease in contrast and inversion of gradation levels.

Further, in the display mode of the present invention, the transmittance is changed by an electric field 207 mainly parallel to the substrate surface, and the electric field 207 is changed.
The intensity E of γ depends on the distance d between the electrodes 201 and 202. Therefore, variations in the distance d between the electrodes 201 and 202 cause variations in brightness, which is a problem. Therefore, high alignment accuracy of the electrodes 201 and 202 is required. Since the alignment accuracy for laminating two substrates is two to three times worse than the alignment accuracy of the photomask, the electrodes 201 and 202 must be formed on the same substrate. However, the electrode 201
Alternatively, when one of the electrodes 202 is used as a common electrode on the same substrate as the substrate on which the thin film transistor element is formed, the number of wirings is increased, short circuits between the scan wirings and the signal wirings are increased, and the yield is lowered. Since the structure of the liquid crystal display device of the present invention does not require the formation of a common electrode, the yield is improved without increasing the number of layers, and in addition to the fact that no transparent electrode is used, a further low cost liquid crystal display device is provided. It will be possible to provide.

Furthermore, the driving means of the present invention, by inputting the two kinds of reference voltage V _R to the pixel from the scanning line, it is possible to lower the driving voltage of the image signal generating means, low power consumption , It becomes possible to provide a low-cost liquid crystal display device.

[0016]

EXAMPLES The present invention will be specifically described with reference to examples.

Example 1 Two glass substrates having a thickness of 1.1 mm and having a polished surface are used as substrates. A nematic liquid crystal composition having a positive dielectric anisotropy Δε of 4.5 and a birefringence Δn of 0.072 (589 nm, 20 ° C.) is sandwiched between these substrates. Although a liquid crystal having a positive dielectric anisotropy Δε is used here, a negative liquid crystal may be used. The polyimide orientation control film applied on the substrate surface is rubbed to obtain a pretilt angle of 3.5 degrees. The rubbing directions on the upper and lower interfaces were substantially parallel to each other, and the angle formed with the direction of the applied electric field was 85 degrees. The gap between the upper and lower substrates was 4.5 μm when the spherical polymer beads were dispersed and sandwiched between the substrates and the liquid crystal was sealed. Therefore, Δn · d is 0.324 μm. The panel is sandwiched by two polarizing plates [G1220DU manufactured by Nitto Denko Corporation], and the polarization transmission axis of one polarizing plate is made substantially parallel (85 °) to the rubbing direction, and the other is orthogonal to it (-5).
°). As a result, normally closed characteristics were obtained.

A pixel as shown in FIG. 1 was formed on one insulating substrate. FIG. 2 shows an equivalent circuit of the pixel, and FIG. 3 shows A of FIG.
A cross section taken along the line, FIG. 4, a cross section taken along the line 1B in FIG.
1 shows a cross section taken along the line C in FIG. 6 shows the system configuration of the liquid crystal display device of the present invention. In this embodiment,
The number of pixels was 640 (× 3) × 480, and the pixel pitch was 110 μm in the horizontal direction and 330 μm in the vertical direction. The scanning wiring 1 was formed using Al in the horizontal direction, was made orthogonal to the scanning wiring 1, and the signal wiring 2 was formed using Cr in the vertical direction. Further, the thin film transistor element 10 using the amorphous silicon 5, a part of the scanning wiring 1 (acting as a gate electrode), the electrode 3, and the electrode 6 was formed in the pixel. Electrode 3
The electrode 4 (which functions as a source electrode of the thin film transistor element 10 but functions as a drain depending on the driving state) functions as one of the pixel electrodes, and the electrode 4 (via the electrode 8 formed in the same layer and the same material as the scanning wiring). The other pixel electrode) is electrically connected. The electrode 6 (which functions as the drain electrode of the thin film transistor element 10 but functions as the source depending on the driving state) is electrically connected to the electrode 7 protruding from the scanning wiring of the next row. 4 and 5
As shown in FIG. 5, through holes were formed in the gate insulating film 14 in order to make contact between the electrodes 3 and 4 and the electrode 8 and between the electrode 6 and the electrode 7. Further, at the intersection of the electrode 8 and the signal wiring 2, the gate insulating film 13 (silicon nitride) of the thin film transistor element 10 was used as a dielectric to form the capacitor element 11. The capacitance element 11 is provided in order to keep the potential difference between the electrodes 3 and 4 and the signal wiring 2 constant, and has the effect of suppressing the voltage fluctuation due to the fluctuation of the potential of the signal wiring 2 in particular. A capacitive element is essential in the display method.

Here, the orientation of the liquid crystal molecules in the liquid crystal layer is controlled mainly by the potential difference (voltage) between the electrodes 3 and 4 and the signal wiring 2. The distance between the electrodes 3 and 4 and the signal wiring 2 was 25 μm. Light is transmitted between the electrodes 3 and 4 and the signal wiring 2 and is incident on the liquid crystal layer to be modulated. Therefore, it is not necessary to provide a pixel electrode having a light-transmitting property (for example, a transparent electrode such as ITO). From the sectional structure of the active matrix type liquid crystal display device, it is possible to eliminate the two transparent electrode layers. In order to shorten the process and suppress the variation of the electric field E applied to the liquid crystal layer due to the alignment accuracy of the mask, the electrodes 3 and 4 and the signal wiring 2 are formed in the same layer, the same material, and the same photomask.

Further, a protective film 14 made of silicon nitride was formed on the thin film transistor element 10 so as to protect the thin film transistor element 10. A substrate 62 (hereinafter, referred to as a counter substrate) opposite to the substrate having the thin film transistor elements is provided with striped R, G, and B color filters 15. A transparent resin 16 for flattening the surface is laminated on the color filter 15. An epoxy resin was used as the material of the transparent resin 16. Further, polyimide-based alignment control films 17 and 18 were applied on the transparent resin 16 and the substrate 62 having the thin film transistor element group. Generally, in the TN type which is the conventional method, the characteristics required for the orientation control film are diverse, and it is necessary to satisfy all of them, so that it is limited to some materials such as polyimide. A particularly important characteristic is the tilt angle. However, the display mode of the present invention does not require a large tilt angle, and therefore,
The choice of materials is significantly improved. Further, in order to eliminate the decrease in contrast due to the influence of the defective alignment region, a non-conductive light-shielding film 19 (organic polymer in this embodiment) was formed on the glass substrate. As a result, no conductive substance is present on the counter substrate 62. In this embodiment, even if a conductive foreign substance is mixed in during the manufacturing process, there is no possibility of inter-electrode contact via the counter substrate 62, and the defective rate due to this is suppressed to zero. Therefore, the margin of cleanliness such as alignment film formation, rubbing, and liquid crystal encapsulation process is widened, and the manufacturing process can be simplified. Further, the light shielding film 19
Since it is made of an organic polymer containing a black pigment, it is possible to prevent glare due to reflection of external light and a decrease in contrast. Further, by laying out the light shielding film 19 in a stripe shape, a printing process can be used.
As a result, the manufacturing process can be further simplified and the cost can be reduced. The thin film transistor substrate 6 formed as described above
The drive LSIs 63 and 64 were connected to 1 and driven.

Next, the drive system will be described. FIG. 7 shows the waveform of the voltage applied to each electrode. Line-sequential driving in which signals are written is performed for each row. When the potential of the scanning line 1 (gate potential) becomes the on level V _G-ON , the potential difference | V _D −V between the potential V _R of the scanning line 9 in the next row and the potential V _D of the signal line 2
_R | = V _SIG is written in the capacitive element 11 through the thin film transistor element 10. When the writing period (on level) of the row ends, the gate potential turns off level VG _-OFF.
Then, the thin film transistor element 10 is turned off and holds the written voltage. Since the liquid crystal is severely deteriorated when it is driven by direct current, it must be driven by alternating current. Therefore, the potential V _R of the scanning line 9 in the next row is set to an intermediate potential between the on level V _G-ON and the off level V _G-OFF (here, V _R = (V _G-ON + V _G-OFF ) / 2). Set to ± V
The voltage of _SIG was applied to the liquid crystal. That is, the potential V _R of the scanning line 9 in the next row plays the role of the common electrode potential of the conventional structure. Also, the gate potential off level V _G-OFF
To V and on level V of the gate potential of the next row
The rising timing until _G-ON is provided with a certain time interval td, and in the present embodiment, td is 3 μs.

As described above, in this embodiment, since there is no transparent electrode, the manufacturing process can be simplified, the yield can be improved, and the cost can be remarkably reduced. In particular, the equipment and process for forming the transparent electrode are not required, and the cost for manufacturing can be reduced because the investment cost for manufacturing equipment is greatly reduced and the number of processes is reduced. Further, since the common electrode is not required, the step of forming the common electrode can be reduced, the contact failure between the common electrode and another electrode can be zero, the yield can be improved, and the cost can be reduced accordingly.

FIG. 8 shows the electro-optical characteristics showing the relationship between the voltage applied to the liquid crystal and the brightness in this embodiment. The contrast ratio is 150 or more when driven by 7V, and the difference in the curves when the viewing angle is changed to the left and right and up and down is extremely small compared to the conventional method (shown in Comparative Example 1), and the display characteristics change almost even when the viewing angle is changed. I didn't. In addition, the liquid crystal alignment was good, and no domain with poor alignment was generated.

In this embodiment, Al and Cr are used as the wiring material, but the material is not particularly limited. In addition, although an amorphous silicon thin film transistor element is used in this embodiment, a polysilicon thin film transistor element or a MOS transistor on a silicon wafer may be used in the case of a reflective display device.

Although the orientation control film is formed in this embodiment, the surface of the flattening film may be directly rubbed as an orientation control film on the flattening film without forming another film. In this case, this epoxy resin has both functions of flattening and controlling the alignment of liquid crystal molecules. This eliminates the step of applying the alignment film, and makes the manufacturing easier and shorter. Similarly, a rubbing treatment can be performed by using an epoxy resin as a protective film for protecting the thin film transistor.

Comparative Example A conventional twisted nematic (TN) type is used as a comparative example. Since the transparent electrode is provided as compared with the first embodiment, the structure is complicated and the manufacturing process is long. As the nematic liquid crystal composition, the one having the same dielectric anisotropy Δε as in Example 1 and a positive value of 4.5 and a refractive index anisotropy Δn of 0.072 (589 nm, 20 ° C.) was used. The gap was 7.3 μm and the twist angle was 90 degrees. Therefore Δn
・ D is 0.526 μm.

An electro-optical characteristic diagram is shown in FIG. The curve changed drastically in the viewing direction. In addition, an alignment defect domain in which the alignment direction of liquid crystal molecules was different from that in the peripheral portion was generated in the vicinity of the gap structure in the adjacent portion of the thin film transistor.

[Embodiment 2] The configuration of this embodiment is the same as that of Embodiment 1 except for the following requirements.

A pixel as shown in FIG. 10 was formed on one insulating substrate. FIG. 11 shows an equivalent circuit of the pixel, FIG. 12 shows a sectional view taken along line D of FIG. 10, and FIG. 13 shows a sectional view taken along line E of FIG.

A thin film diode element 20 (Metal-Insulator-Metal) was formed by the scanning wiring 1, the electrode 23 and the insulating film 21. Ta is used for the scanning wiring 1, and the insulating film 21 is
TaOx in which Ta was anodized was used. The scanning wiring 1 and the signal wiring 2 are insulated by an insulating film 22 (silicon nitride in this embodiment). The orientation of the liquid crystal is controlled by the potential difference between the electrodes 23 and 24 and the signal wiring 2. In addition, the capacitive element 11
Are formed of the signal line 2, the electrode 25 connecting the electrode 23 and the pixel electrode 24 (formed at the same time when the scanning line 1 is formed), and the insulating film 22. As shown in FIGS. 12 and 13, through holes were formed in the gate insulating film 22 to make contact between the electrode 23 and the insulating film 21 and between the electrodes 23 and 24 and the electrode 25. In this embodiment, the through hole is formed in the insulating film 22, but the insulating film 22 may be left only at the intersection of the scanning wiring 1 and the signal wiring 2 and the intersection of the signal wiring 2 and the electrode 25. .

The drive voltage waveform of this embodiment is shown in FIG.
The driving method is as follows: when a scan pulse is applied to the scan line 1, a sufficient voltage is applied between the scan line 1 and the pixel electrode 23, and the thin film diode element 20 becomes conductive.
The voltage between the signal line 2 and the signal line 2 charges the capacitor 11. After the thin-film diode element 20 is turned off, the potential of the signal wiring 2 changes as in the first embodiment, but the potentials of the pixel electrodes 23 and 24 also change in the same manner depending on the capacitance element. No matter how the wiring 2 changes,
The potential difference between the pixel electrodes 23 and 24 and the signal line 2 is constant.

In this embodiment, the same effect as that of the first embodiment can be obtained. Further, by using the thin film diode element, the wiring in the pixel is simplified, and the planar structure of the pixel is simplified. The yield was improved. In addition, the area of the effective portion (opening) that transmits light can be increased by about 30%, and by increasing the transmittance, a brighter liquid crystal display device could be obtained.

[Third Embodiment] The configuration of this embodiment is the same as that of the first embodiment except for the following requirements.

FIG. 15 shows the drive voltage waveform of this embodiment.
When the potential (gate potential) of the scanning wiring 1 becomes the on level V _G-ON , the potential V _R ± V _B of the scanning wiring 7 in the next row and the signal wiring 2
Potential difference V _D − (V _R ± V _B ) | = V _SIG of the potential V _D of V is written in the capacitive element 11 through the thin film transistor element. Therefore, the potential V _D of the signal wiring 2 is V _SIGW +
It _suffices if the potential is in the range of V _R −V _B to −V _SIGW + V _R + V _B. Here, V _SIGW is a liquid crystal applied voltage necessary for displaying white. Therefore, the maximum potential V of the signal wiring 2
The potential difference between _Dmax and the minimum potential V _Dmin is 2 (V _SIG −V _B ), and the signal side drive LSI 64 may output a voltage of 2 (V _SIG −V _B ).

Therefore, V _SIGW = 7V and V _{B is set} to 5
When V is set, 2 (V _SIG −V _B ) = 4 V, and the maximum amplitude of the signal side drive LSI 64 becomes 4 V. Therefore, in this embodiment, the signal side drive LSI 64 is an LSI (5 V withstand voltage LSI) formed by a normal process. ) Can be used. Therefore, the cost of the signal side drive LSI 64 can be significantly reduced. Furthermore, since the power consumption is also proportional to the square of the voltage, the power consumed on the signal side can be reduced to about 33%.

In this embodiment, in addition to the effects of the first embodiment, the cost of the signal side drive LSI 64 can be greatly reduced, and the power consumption can be greatly reduced.

[0037]

According to the present invention, the pixel electrode does not need to be transparent, an opaque metal electrode can be used, and a low-cost active matrix liquid crystal display capable of mass production with low-cost equipment and high yield. The device is obtained. In addition, there is no need to form a common electrode, the number of steps involved in the formation of the common electrode can be reduced, and the reduction in the yield associated with the formation of the common electrode can be solved. The device is obtained. Further, an active matrix type liquid crystal display device having a simple driving circuit and low voltage and low power consumption can be obtained. On the other hand, an active matrix type liquid crystal display device having good viewing angle characteristics and easy multi-gradation display can be obtained at the same time.

[Brief description of drawings]

FIG. 1 is a plan view of a pixel portion according to a first embodiment of the present invention.

FIG. 2 is an equivalent circuit diagram of FIG.

FIG. 3 is a sectional view taken along the line A in FIG.

FIG. 4 is a sectional view taken along line B of FIG.

5 is a sectional view taken along line C of FIG.

FIG. 6 is an explanatory diagram of a liquid crystal display device of the present invention.

FIG. 7 is a voltage waveform diagram applied to each electrode of FIG.

FIG. 8 is a characteristic diagram showing viewing angle dependence of the liquid crystal display device of the present invention.

FIG. 9 is a characteristic diagram showing viewing angle dependence of a conventional liquid crystal display device.

FIG. 10 is a plan view of a pixel portion according to a second embodiment of the present invention.

11 is an equivalent circuit diagram of FIG.

12 is a sectional view taken along the line D in FIG.

13 is a sectional view taken along the line E of FIG.

14 is a voltage waveform diagram applied to each electrode of FIG.

FIG. 15 is a voltage waveform diagram applied to each electrode of Example 3 of the present invention.

FIG. 16 is an explanatory diagram showing a liquid crystal operation in the liquid crystal display device of the present invention.

[Explanation of symbols]

1 ... Scan wiring, 2 ... Signal wiring, 3, 4 ... Pixel electrode, 5 ...
Semiconductor thin film, 6 ... Drain electrode of thin film transistor element, 7 ... Electrode protruding from the scanning wiring of the next row, 8 ... Electrode.

Claims (6)

[Claims] 1. A pair of substrates and a liquid crystal composition layer sandwiched between the substrates, wherein a plurality of scanning wirings and signal wirings are arranged in a matrix on one of the substrates, The region is divided into a plurality of pixel regions, and in each of the pixel regions, an active element and a capacitive element are arranged in a state of being electrically connected to the liquid crystal composition layer, and the active element and the capacitive element are provided. A liquid crystal display device comprising an element connected to any one of the wirings to form a liquid crystal drive circuit, each scanning wiring connected to a scanning signal generating means, and each signal wiring connected to a video signal generating means, The liquid crystal molecules of the liquid crystal composition layer maintain the major axis direction of the liquid crystal molecules substantially parallel to the substrate surface according to the electric field strength according to the potential difference between the pixel electrode connected to the active element and the signal wiring. While A liquid crystal display device which operates. 2. The liquid crystal display device according to claim 1, wherein the capacitive element includes a pixel electrode and a signal line. 3. The liquid crystal display device according to claim 1, wherein the active element is a transistor element. 4. The liquid crystal display device according to claim 1, wherein the active element is a diode element. 5. A pair of substrates and a liquid crystal composition layer sandwiched between the substrates, wherein a plurality of scanning wirings and signal wirings are arranged in a matrix on one of the substrates, and the scanning wirings and the signal wirings are arranged on the substrate. The region is divided into a plurality of pixel regions, and in each of the pixel regions, a transistor element and a capacitor element are arranged in a state of being electrically connected to the liquid crystal composition layer, and the transistor element and the capacitor element are provided. A liquid crystal display device comprising an element connected to any one of the wirings to form a liquid crystal drive circuit, each scanning wiring connected to a scanning signal generating means, and each signal wiring connected to a video signal generating means, The scanning signal generating means has means for generating a voltage for turning on the transistor element, a voltage for turning off the transistor element, and a voltage to be input to the pixel electrode. A liquid crystal display device comprising: 6. The liquid crystal display device according to claim 5, wherein said scanning signal generating means has means for generating a binary value or more of a voltage input to said pixel electrode.