JPH07199205A - Liquid crystal display element - Google Patents

Abstract

PURPOSE:To generate walls and to obtain a light scattering effect by forming an electrode structure in which conductor parts are electrically connected for each of respective pixels into molecular arrangement in which the tilt directions of liquid crystal molecules are capable of taking >=2 directions when an electric field is impressed to a liquid crystal layer by non-conductor parts. CONSTITUTION:The diagonal electric field (e) is applied to the liquid crystal layer 20 when a voltage is impressed thereto with the element structure formed by forming a common electrode 13 on an upper substrate 11 and plural pieces of pixel electrodes 14 on a lower substrate 12, depositing upper and lower oriented films 15, 16 on both electrodes 13, 14 and packing the liquid crystal layer 20 between the upper and lower oriented films 15 and 16. The liquid crystal molecules are oriented in the direction of this electric field (e) and, therefore, the directions of the liquid crystal molecules M are made symmetrical with the center of the electrodes on the striped conductor parts 13a and the nonof the liquid crystal molecules are opposed to each other in the central part of the electrodes, the walls DL1, DL2 are formed in these parts. The light scattering is obtd. by two kinds of these walls DL1, DL2.

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.

[0002]

2. Description of the Related Art When a liquid crystal display element is classified from the viewpoint of light control, a change in brightness is caused by a combination of a polarization effect of liquid crystal molecules and a polarizer, and a phase transition of liquid crystal is used to scatter and transmit light. It can be classified into those which are caused and those which are caused by the change in color shade by controlling the visible light absorption amount of the dye by adding a dye.

A liquid crystal display element combining the former polarization effect and a polarizer is, for example, a twisted nematic (TN) type liquid crystal having a 90 ° twisted molecular arrangement, and in principle, polarization control is performed with a thin liquid crystal layer thickness and a low voltage. Therefore, it has a fast response speed, low power consumption, high contrast ratio, clock, calculator, simple matrix drive, active matrix drive with switching element for each pixel, and in combination with color filter, It is applied to LCD TVs with full-color display.

However, a liquid crystal display device combining such an effect with a polarizer has a remarkably low transmittance since it uses a polarizing plate in principle, and the display color depends on the viewing angle and direction due to the orientation of the molecular arrangement. Has a viewing angle dependence such as a large change in the contrast ratio and the contrast ratio.
The display performance of T) cannot be completely exceeded.

On the other hand, the latter one utilizing the phase transition of liquid crystal and the liquid crystal display element in which the visible light absorption amount of the dye is controlled are, for example, from a cholesteric phase having a helical molecular arrangement to a homeotropic molecular nematic phase. -Type liquid crystal that causes phase transition to liquid crystal by applying an electric field and a white tailor (White)
-Taylor) type GH liquid crystal, without using a polarizer,
Since it does not use the polarization effect in principle, it is bright and has a wide viewing angle, and is applied to automobile equipment and projection type displays.

However, in order to obtain sufficient light scattering, it is necessary to sufficiently thicken the liquid crystal phase and to increase the helical strength that causes the scattering, which requires a high driving voltage and a very slow response speed. Therefore, it has been difficult to apply it to a display element having a large display amount (number of pixels). In addition, it has been considered difficult to provide gradation because the transmittance changes abruptly as the applied voltage increases.
Further, the applied voltage-transmittance characteristic has a hysteresis, and there is a practical problem that it is difficult to perform multiplex driving.

Further, as a scattering mode liquid crystal display element, there is an NCAP type liquid crystal display element in which a liquid crystal 4 is spherically held in an organic polymer 3 sandwiched between substrates 1 and 2 as shown in FIG.
Since this element does not use a polarizing plate, it exhibits a bright and wide viewing angle and is applied to automobile equipment, projection type displays and the like.
However, the voltage applied from the outside is divided between the organic polymer and the liquid crystal, and only a part of the applied voltage is applied to the liquid crystal, so that there is a problem that the operating voltage is increased practically. Moreover, in order to obtain sufficient light scattering, it is necessary to make the liquid crystal thick enough, and the response speed is extremely slow. Therefore, it is applied to a display device with a large amount of display (number of pixels). Was considered difficult. Further, the applied voltage-transmittance characteristic has a hysteresis, and there is a practical problem that it is difficult to perform multiplex driving. The polymer dispersion type liquid crystal display device in which liquid crystal is held in a network organic polymer that operates according to the same operation principle has the same problem.

[0008]

As described above, at present, liquid crystal display elements have problems that they have low transmittance, have different viewing angles, require high driving voltage, and have slow response speed.

Against this background, the inventors of the present invention, in Japanese Patent Application No. 5-184273, filed from a nematic liquid crystal composition between two substrates each having electrodes forming a plurality of pixels facing each other. The liquid crystal layer is sandwiched between the electrodes, and the electrodes of the both substrates are made up of a conductive portion and a non-conductive portion in units of a fine region for each pixel. A liquid crystal display element is proposed in which at least a part of the non-conductor parts of the electrodes are arranged to face each other.

In this liquid crystal display element, in each pixel, a light-transmitting state is formed by an effectively uniform molecular arrangement, and a wall-like molecular arrangement is formed at the boundary between the two or more electric field directions, and A scattering state is obtained, and the above-mentioned problems can be solved.

An example of the molecular arrangement structure of this liquid crystal display element is a so-called splay arrangement and a molecular arrangement in which twisting is added thereto, and the pretilt angles of liquid crystal molecules on the upper and lower substrate surfaces are substantially equal in the vertical direction. In such a molecular arrangement, the tilt directions of the molecules are two directions depending on how the electric field is applied. This is because the liquid crystal molecule arrangement in the state where no voltage is applied is symmetrical between the upper half and the lower half of the liquid crystal layer. This is because the tilt direction of the liquid crystal molecules has two or more degrees of freedom.

Therefore, only when a voltage is applied, a disclination line is formed like a wall in the liquid crystal layer along the non-conductor portion of the electrode at the boundary in the tilt direction of the molecule.
This disclination line is called a "wall". This wall can obtain the function of scattering incident light. In order to allow the liquid crystal molecules to have two or more degrees of freedom in the tilt direction, for example, a nematic liquid crystal composition having a negative dielectric anisotropy is used as the liquid crystal composition, and the liquid crystal molecule alignment is performed on the upper and lower substrates. The same effect can be obtained even with a completely vertical arrangement in which the pretilt angle is 90 °. In this case, the degree of freedom in the tilt-down direction of the liquid crystal molecules is 2 or more.

In any case, the liquid crystal molecules have an effectively uniform molecular arrangement in the state where no voltage is applied, and the liquid crystal molecules are tilted up (the tilt angle is increased) or tilted down (the tilt angle is increased). The above-mentioned problem is encountered in the case of an electrode in which the oblique electric field is applied in two or more directions which are contradictory to each other in a fine region with respect to the liquid crystal molecule array having two or more degrees of freedom in the direction in which the tilt angle is decreased). It is possible to obtain excellent display performance which is solved.

The present invention is the above-mentioned Japanese Patent Application No. 5-184.
In the same way as the electrode structure proposed in No. 273, a new electrode structure for generating a wall to obtain a light scattering effect is proposed,
Further, it is intended to further increase the productivity of this liquid crystal display device.

[0015]

As a means for solving the above problems, the present invention sandwiches a liquid crystal layer made of a nematic liquid crystal composition between two substrates each having electrodes forming a plurality of pixels facing each other. In the liquid crystal display element formed by
The electrode of one of the substrates has an electrode structure in which each pixel is composed of a conductor portion having a non-conductor portion sandwiched therebetween, and at least the conductor portion is electrically connected to one for each pixel. Due to the presence of the body part, molecules in which the tilt directions of the liquid crystal molecules (tilt up direction when the dielectric anisotropy of the liquid crystal is positive, tilt down direction when the dielectric anisotropy of the liquid crystal is negative) can be two or more directions when an electric field is applied to the liquid crystal layer. A liquid crystal display device characterized by being arranged.

Further, a liquid crystal display device is obtained in which the electrode structure of each pixel has a stripe shape of a conductor portion and a non-conductor portion.

Further, fine particles having a dimension in the normal direction of the substrate shorter than the liquid crystal layer thickness are mixed in the gap between the substrates, or a protrusion having a dimension in the normal direction of the substrate lower than the liquid crystal layer thickness is provided. A liquid crystal display device provided on at least one of both substrates is obtained.

[0018]

The present invention achieves the above object, and the principle and method of achieving the same will be described below.

As shown in FIG. 6, a common electrode 13 is formed on an upper substrate 11 and a plurality of pixel electrodes 14 are formed on a lower substrate 12, and vertical alignment films 15 and 16 are formed on both electrodes 13 and 14, respectively. Then, in the device structure in which the liquid crystal layer 20 is filled between the upper and lower alignment films 15 and 16, the common electrode 13 facing the pixel electrode 14 is provided with a plurality of striped conductor portions 13a and the non-conductor portion 13b is provided between them. The shapes are separated. That is, a pattern of a plurality of stripe-shaped conductor portions 13a is formed in a region corresponding to one pixel. The striped conductor portions 13a are commonly connected at their ends, and the regions corresponding to other pixels are integrated to form the common electrode 13.

Further, the alignment treatment direction a of the upper alignment film 15
Then, the alignment processing direction b of the lower alignment film 16 is intersected with the molecules M of the liquid crystal layer so as to form a splay alignment (in the figure, the crossing angle is set to zero).

When the driving power source 21 is turned on and the voltage is applied between the electrodes 13 and 14, the electric field is concentrated on the conductor portion 13a of the common electrode 13 without being uniformly applied in the thickness direction of the liquid crystal layer. Is generated as described above, and an oblique electric field is generated as indicated by the line of electric force e. For this reason, the long axis of the liquid crystal molecules M is arranged to be inclined along the electric field, and a boundary in which the molecular arrangement is disturbed occurs at the portion where the inclination of the oblique electric field is reversed. This boundary is referred to as a disclination line (DL1 and DL2 in the drawing), but in the present invention, the disclination line extends along the stripe of the conductor portion 13a and is formed like a wall. A Lining Wall (abbreviated as Wall) can be formed. . This wall DL1
, DL2 part cannot control the polarized light and causes light scattering. In the present invention, the display is performed by electrically controlling the generation of the wall by utilizing this light scattering phenomenon. In the invention of Japanese Patent Application No. 5-184273 of the above-mentioned prior application, a stripe-shaped conductor portion is provided on both electrodes to generate a wall. Since the conductor portion having the same function is formed, the manufacturing process can be simplified.

Further, the generation of the wall will be described below.

When a voltage is applied, an oblique electric field is applied to the liquid crystal layer 20. Since the liquid crystal molecules are oriented in the direction of the electric field e, the directions of the liquid crystal molecules M are bilaterally symmetrical at the centers of the electrodes on the striped conductor portion 13a and the non-conductor portion 13b which is a space as shown in the figure. Since the rising tilts of the liquid crystal molecules are opposite to each other in the central portion of this electrode, the walls DL1 and D1 are formed in this portion as described above.
L2 is formed. In the case of the electrode structure of the present invention, since one electrode has a flat plate structure, the two walls DL1 and DL2 shown in the figure differ in the principle of appearance. Wall D
L1 is generated by breaking the electric field direction at the center of the non-conductor portion 13b regardless of the width of the non-conductor portion 13b of the electrode. On the other hand, the wall DL2 is generated when the ends of the cracked electric field described above substantially overlap on the left and right. Therefore, it does not appear if the width of the non-conductor part is too wide. It is a feature of the electrode structure of the present invention that light is scattered by these two types of walls. In the case of the electrode structure of the present invention, light scattering is obtained by two kinds of walls, and therefore, the electro-optical characteristics thereof are different from the electrode structure shown in the above-mentioned Japanese Patent Application No. 5-184273. Specifically, the characteristics are gentler than those of the electrode configuration shown in the above-mentioned prior application. Therefore, the driving voltage is slightly higher than that of the prior application, but the driving becomes easier when performing gradation display. Further, since one of the electrodes is substantially a flat plate, the alignment of the upper and lower substrates in the pixel is not required in manufacturing.

The generation of the wall depends on the stripe shape of the conductor portion. FIG. 7A shows an electrode having a fine pattern (upper electrode) having a zigzag stripe shape, and FIG. 8A shows an electrode having a parallel stripe shape. As is apparent from the figure, in the case of the configuration of FIG. 8A, the planar shapes of the walls DL1 and DL2 are straight lines. On the other hand, when the zigzag stripe shape is formed as shown in FIG. 7A, the planar shapes of the walls DL1 and DL2 are not straight lines. Each of these two shapes has advantages. The appearance of the wall is because the tilt directions of the liquid crystal molecules are slightly different by 180 °, but when viewed in plan, the tilt directions of the molecules are the same. That is, when observed from above the element, the molecules are tilted in a uniform azimuth. Therefore, as a result, the light scattering direction is almost only this liquid crystal molecule alignment direction in a plan view. As shown in FIG. 8B, light having a parallel stripe shape causes almost linear light scattering. Therefore, one polarization component of the incident light is strongly scattered, but the other polarization component is weak. On the other hand, in the case of the zigzag stripe shape as shown in FIG. 7A, the light scattering shape has various directions as shown in FIG. 7B, and accordingly strong scattering is obtained.

However, as shown in FIG. 8A, the parallel stripes have a straight wall in plan view, and the wall density can be higher than that of the structure shown in FIG. 7A. This is because the molecular alignment of the liquid crystal is more orderly than the configuration of FIG. Therefore, as a result, high scattering characteristics can be obtained with both the configuration of FIG. 7 and the configuration of FIG. It is preferable to use the respective features properly according to the optical system when these liquid crystal display elements are used as projection display elements.

Now, these various electrode configurations of the present invention,
When the above-mentioned wall is generated in the molecular arrangement, since the oblique electric fields are configured to be reciprocal in each fine region, even if a voltage is continuously applied, the liquid crystal molecule is It is difficult to maintain the molecular arrangement in the generated state. This is because it is difficult to change the arrangement shape of the liquid crystal molecule array so finely. In other words, the force for maintaining such a difficult molecular arrangement form is insufficient only by the external force such as the electric field and the magnetic field. In order to solve such a problem, the inventors have mixed fine particles having a length in the thickness direction of the liquid crystal layer shorter than the thickness d of the liquid crystal layer into the gap between the substrates, or a height in the thickness direction of the liquid crystal layer of the liquid crystal layer. It has been found that providing protrusions with a thickness lower than the thickness d on at least one of both substrates solves the problem.

FIG. 9 shows an outline of this configuration. As shown in the figure, it has a structure in which fine particles smaller than the liquid crystal layer thickness are added. In this way, when fine particles or protrusions are provided in the liquid crystal layer, if the fine particles or protrusions are present at the place where the wall appears,
Due to the presence of these, it is possible to maintain the above-mentioned molecular arrangement state by minutely changing the arrangement shape, that is, the molecular arrangement state in which a large number of walls appear. In the present invention, since such fine particles and projections have a function of maintaining a large number of walls, they are referred to as "wall supports". As means for obtaining such a function, in addition to the method described in FIG. 9, fine particles having a size equal to the thickness of the liquid crystal layer are mixed into the liquid crystal layer more than necessary (that is, a substrate gap agent is mixed). Can also be obtained by

However, in this case, in order to maintain a large number of walls, it is necessary to mix a large number of substrate gap agents, which adversely affects the light transmission state. Specifically, there is an influence of light scattering by the substrate interstitial agent and light scattering by the liquid crystal molecule alignment on the surface of the substrate interstitial agent. In order to reduce these influences, it is desirable to use, as the wall support, fine particles or protrusions having a smaller thickness than the liquid crystal layer thickness d. The inventors have confirmed through experiments that the light scattering caused by these particles and projections can be brought to a problem-free level by using the particles and projections smaller than the liquid crystal layer thickness d.

In addition to the above-mentioned fine particles and projections, the present inventors have found that the function of this wall support is T.
It has been confirmed that the steps (steps caused by the thickness of the wiring electrodes and the semiconductor layer) inevitably provided on the FT and MIM substrates have similar functions in the vicinity of the steps.

[0030]

EXAMPLES Examples of the liquid crystal display device of the present invention will be described in detail below.

(Embodiment 1) FIGS. 1 and 2 show an embodiment in which the present invention is applied to a liquid crystal display device for a projection type display. In FIGS. 1 (a) and 1 (b), a glass upper substrate 11 is used. Has an upper electrode, that is, a common electrode 13 formed by patterning ITO on one surface and an upper alignment film 15 of polyimide deposited thereon. Upper substrate 11
A black matrix (not shown) of chrome is formed in the non-pixel region of the.

A plurality of lower electrodes of ITO, that is, pixel electrodes 14 are arranged in a mosaic pattern on the lower substrate 12 of glass which serves as cells of the display element together with the upper substrate 11. As shown in FIG. 2, each pixel electrode 14 has a TFT switching element 30 and is connected to an address line 31 and a signal line 32 provided on the same substrate.

The common electrode 13 has a non-conductor portion 13b as a space between them so that a plurality of zigzag stripe conductor portions 13a having a width of 8 μm are formed in a region facing each pixel electrode 14. The conductor portions 13a are arranged at predetermined intervals. Zigzag peak-to-peak width is 1
It is 0 μm. The pixel electrode 14 has a square flat plate shape and has an area of 70 μm × 70 μm. The area for one pixel including this pixel electrode is 100 μm × 100 μm,
The window grid portion formed by the corresponding conductor portion 13a and non-conductor portion 13b is 70 μm × 70 μm. A polyimide (trade name SE-7120, manufactured by Nissan Chemical Industries, Ltd.) having a pretilt angle of 6 ° is formed as the upper and lower alignment films 15 and 16, and as shown in FIG. After rubbing both substrates 11 and 12 in the direction), a substrate interstitial agent (fine particles made by Sekisui Fine Chemical: Micropearl SP, particle size 7.) is formed on the lower substrate 12 side so that the liquid crystal layer thickness is 7.5 μm. 5 um) with a dispersion density of 100 /
It was sprayed by a dry spraying method so as to have a size of mm ² . A liquid crystal display device in which a liquid crystal material having a dielectric anisotropy Δn of 0.2030 (positive) (product name ZLI-3926, manufactured by Merck Japan) is sandwiched between these substrates to form a liquid crystal layer 20 and the substrate is sealed as a cell. Got Here, the reason why the liquid crystal layer thickness is increased to 7.5 μm and Δn of the liquid crystal composition is increased is to enhance the light scattering property in the light scattering state.

The liquid crystal display device thus obtained has T
When a voltage is applied from the power source through the FT switching element 30, walls DL1 and DL2 are generated as shown in FIG. 1 (c). This electro-optical characteristic (transmittance-applied voltage curve)
In order to obtain, the He-Ne laser light was made incident on the liquid crystal display device and the transmittance was measured. The spot diameter of light is 2mm,
The transmitted laser light was detected by a photodiode located at a distance of 20 cm from the liquid crystal display device.

In FIG. 5, the applied voltage is gradually changed from 0V to 3.3V.
3 shows a transmittance-applied voltage curve (Example 1) when the voltage was increased to 3.3 V and gradually decreased from 3.3 V to 0 V. The transmittance is about 80 when no voltage is applied (0 V is applied).
%, Showing a bright transmittance characteristic. In addition, the applied voltage 3.
At 3 V, the minimum transmittance was 0.4%, and a good scattering state was obtained. As is clear from the figure, there was no hysteresis in the electro-optical characteristics. Moreover, when the response speed was measured at an applied voltage of 3.3 V and 0 V, it rose to 6 ms.
ec, the fall was 18 msec, which was an extremely fast value.

Next, a voltage was applied and the maintenance state of the wall was examined by observing the molecular arrangement by a polarization microscope and measuring the light scattering state by measuring the transmittance. In this example, when the applied voltage of 3.3 V was continuously applied, it was confirmed that the initial wall arrangement was maintained even after 1 hour.

Further, in this embodiment, since the pixel electrode is a flat plate electrode having no non-conductor portion, alignment with a fine pattern of the common electrode is not required, so that the manufacturing process is simplified and production is performed. It has excellent properties.

Example 2 FIGS. 3 and 4 show the structure of the display device of this example. The first embodiment shown in FIGS.
The parts having the same reference numerals as those are the same parts and the explanations thereof are omitted. In the figure, the common electrode 23 formed on the upper substrate 11 is the pixel electrode 1
A plurality of straight stripe-shaped conductor portions 23a for each pixel in the region A opposed to the non-conductor portion 2 which separates these conductor portions from each other.
And 3b. Conductor portion 23a, non-conductor portion 23b
Both are 8 μm apart, and the area A is 70 μm × 70 μm
Thus, the pixel electrode is also formed to have the same size.

A TFT switching element 3 is provided between these electrodes.
When a voltage is applied from the power source 21 via 0, walls DL1 and DL2 as shown in FIG. 12 are generated.

The electro-optical characteristics (transmittance-applied voltage curve) of the device of this example were measured in the same manner as in Example 1. As shown in FIG. 5, the applied voltage is gradually increased from 3.2V to 3.2V.
Transmittance when gradually decreasing from V to 0V-
The applied voltage curve (Example 2) is shown. When no voltage was applied (0 V was applied), the transmittance was 80%, which was a bright transmittance characteristic. Further, at the applied voltage of 3.2 V, the minimum transmittance was 0.4%, and the favorable scattering state of Example 1 or higher was obtained. As is clear from the figure, there was no hysteresis in the electro-optical characteristics. Moreover, when the response speed characteristics were measured at an applied voltage of 3.2 V and 0 V, the rising time was 6 ms.
A very fast value of ec and a fall of 18 msec was obtained.

Next, the wall-maintaining state during voltage application was examined by observing the molecular arrangement by a polarization microscope and measuring the light-scattering state by transmittance measurement, and in this example, an applied voltage of 3.2 V was continuously applied. In this case, it was confirmed that the initial wall alignment was maintained even after 1 hour.

(Embodiment 3) As shown in FIG.
Using the same substrate as the above, the alignment film 15,
After the alignment treatments F and R are applied to 16, the wall support 33 (trade name: Micropearl, manufactured by Sekisui Fine Chemical Co., Ltd.) made of fine particles having a particle size of 5 μm is provided on the side of the upper substrate 11 so that the dispersion density is 1000 pieces / mm ^2. Then, the element was sprayed by the dry spraying method, and the subsequent steps were performed using the same method and materials as in Example 1 to obtain the device of this example. When various characteristics were measured,
The same characteristics as in Example 1 were obtained, and the applied voltage 3.3.
When V was continuously applied, it was confirmed that the initial wall alignment was maintained even after 10 hours had passed.

[0043]

According to the present invention, it is not necessary to use a polarizing element, and it is possible to obtain a bright element having excellent scattering characteristics, a low driving voltage, and a high contrast ratio. In addition, even in gradation display, an element having a very wide viewing angle that does not cause a display reversal viewing angle can be obtained. Moreover, such an element can be practically obtained by a simple manufacturing process. Further, it is suitable for a display of a large display capacity driven by a TFT, and also suitable for application to a projection display.

[Brief description of drawings]

1A and 1B are views for explaining an embodiment of the present invention, in which FIG. 1A is a partial perspective view, FIG. 1B is a sectional view taken along line XX ′ in FIG. 1A, and FIG. FIG.

2A and 2B are diagrams illustrating an embodiment of the present invention, in which FIG. 2A is a plan view of a common electrode, and FIG. 2B is a plan view of a pixel electrode.

FIG. 3 illustrates another embodiment of the present invention.
Is a partial perspective view, and (b) is a cross-sectional view of (a) taken along line XX ′.

FIG. 4 illustrates another embodiment of the present invention.
Is a plan view of the common electrode, and (b) is a plan view of the pixel electrode.

FIG. 5 is a curve diagram showing a transmittance-applied voltage characteristic of the example of the present invention.

FIG. 6 is a schematic cross-sectional view illustrating the operation of the present invention.

7A and 7B are plan views illustrating the operation of the present invention.

8A and 8B are plan views illustrating the operation of the present invention.

FIG. 9 is a schematic sectional view for explaining the operation of the present invention.

FIG. 10A is a sectional view showing a conventional structure.

[Explanation of symbols]

 11 ... Upper substrate 12 ... Lower substrate 13 ... Common electrode 13a ... Conductor part 13b ... Non-conductive part 14 ... Pixel electrodes DL1, DL2 ... Wall

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Masahito Ishikawa, No. 8 Shinsugita-cho, Isogo-ku, Yokohama-shi, Kanagawa Stock company, Toshiba Yokohama Works (72) Inventor, Hitoshi Hato, No. 8, Shinsugita-cho, Isogo-ku, Yokohama, Kanagawa Company Toshiba Yokohama Office

Claims (3)

[Claims] 1. A liquid crystal display device comprising a liquid crystal layer made of a nematic liquid crystal composition sandwiched between two substrates each having electrodes facing each other to form a plurality of pixels. For each, it is an electrode structure consisting of a conductor part having a non-conductor part sandwiched between them, and at least each pixel has an electrically connected conductor part, and due to the presence of the non-conductor part, A liquid crystal display device characterized in that the tilt direction of liquid crystal molecules when an electric field is applied to the liquid crystal layer is a molecular arrangement in which two or more directions can be taken. 2. The liquid crystal display element according to claim 1, wherein the electrode structure of each pixel is such that the conductor portion and the non-conductor portion have a stripe shape. 3. A fine particle having a dimension in the normal direction of the substrate shorter than the liquid crystal layer thickness is mixed into the gap between both substrates, or a protrusion having a dimension in the normal direction of the substrate lower than the liquid crystal layer thickness is formed. The liquid crystal display device according to claim 1 or 2, wherein the liquid crystal display device is provided on at least one of both substrates.