KR19990088500A - Liquid Crystal Display Device - Google Patents

Abstract

The present invention relates to a liquid crystal display device. In particular, it is to improve the display quality by eliminating the non-operating region of the liquid crystal generated in the region between the display electrode and the reference electrode.

The liquid crystal display according to the present invention includes a transparent substrate disposed so that liquid crystals are disposed to face each other, and reference electrodes arranged substantially continuously orthogonally to a reference signal line, and the reference electrode 4A supplied with a reference signal through the reference signal line. And a pixel electrode 10 arranged in parallel with the reference electrode, wherein a boundary line of the reference electrode in the vicinity of the reference signal line includes a pixel electrode and a reference electrode in a portion parallel to the pixel electrode. It is characterized by inclined to form an acute angle (90-ψ) with the electrode direction generated between.

Description

Liquid Crystal Display Device

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device, and more particularly to a liquid crystal display device called a transverse electric field system.

Recently, a liquid crystal display device called a lateral electric field method has been known. In this regard, the conventional liquid crystal display device is called a longitudinal electric field method. That is, the term "electric field system" includes electrodes on each of the transparent substrates arranged opposite to each other with the liquid crystal interposed therebetween, and the light transmittance of the liquid crystal is changed by generating an electric field perpendicular to the transparent substrate by these electrodes. It is configured to let.

On the other hand, what is called a transverse electric field system has the effect of allowing an image to be recognized at a so-called wide viewing angle at which a clear image is obtained even when the display surface is observed in a large angular direction with respect to the display surface.

Such a liquid crystal display device is described in detail in, for example, Japanese Patent Application Laid-Open No. 5-505247 and Japanese Patent Application Laid-Open No. 63-21907.

As described in the above document, there are a plurality of display electrodes and reference electrodes for each pixel region, and are arranged to cross each other so that an electric field is generated between adjacent display electrodes and reference electrodes.

In this case, one end of each display electrode is commonly connected so that an image signal (voltage) is applied thereto, and each reference electrode is connected through a reference signal line with one end thereof commonly connected by a reference signal line. A signal (voltage) is applied.

However, it has been confirmed that the liquid crystal display device configured as described above has a non-operational region in which the light transmittance does not change, particularly in a region between the display electrode where the electric field is generated and the reference voltage, particularly near the reference signal line. .

As a result of identifying the cause, most of the area between the display electrode and the reference voltage generates an electric field in a direction orthogonal to the longitudinal direction of each of the electrodes, but in a portion close to the reference signal line, It has been found that this is due to the changing direction of the affected electric field.

SUMMARY OF THE INVENTION The present invention has been made on the basis of the above circumstances, and an object of the present invention is to provide a liquid crystal display device which eliminates the non-operation area generated in the area between the display electrode and the reference electrode and improves the display quality. .

Among the inventions disclosed in the present application, an outline of representative ones will be briefly described as follows.

Sudan 1.

On the surface of the liquid crystal side of one of the transparent substrates disposed to face each other with the liquid crystals interposed therebetween, reference electrodes arranged substantially orthogonally from the reference signal lines and pixel electrodes arranged in parallel with the reference electrodes are formed.

In the liquid crystal display device for controlling the transmittance of light transmitted between the electrodes by generating a rotational twist on the molecules regulated in the initial alignment direction of the liquid crystal by the electric field generated between the pixel electrode and the reference electrode,

The reference electrode, along with the reference signal line in the vicinity of the connection portion with the reference signal line, shifts the direction of the electric force line of the electric field generated between the pixel electrode in the initial alignment direction of the liquid crystal molecules and in a direction perpendicular to the initial alignment direction. It is characterized by being configured to have an angle with respect to.

Sudan 2

In the configuration of the means 1, the liquid crystal has positive dielectric anisotropy, and the connection portion of the reference electrode with respect to the reference signal line becomes wider as the reference signal line is closer to the reference signal line, and the portion of the wide width is for display as seen from the liquid crystal side. It is characterized by the left side with respect to an electrode.

Sudan 3

In the configuration of the means 1, the liquid crystal has negative dielectric anisotropy, and the connection portion of the reference electrode with respect to the reference signal line is formed to be wider as the reference signal line is closer to the reference signal line. It is characterized by the right side with respect to the molten electrode.

In the liquid crystal display device configured as described above, the direction in which the electric force lines generated between the display electrode and the reference electrode are directed to the liquid crystal molecules is not changed in the vicinity of the reference signal line but is uniform.

From this, the non-operational region of the liquid crystal generated in the region between the display electrode and the reference electrode can be eliminated, and the display quality can be improved.

1 is a sectional view of principal parts showing one embodiment of a liquid crystal display according to the present invention.

2 is a schematic configuration diagram showing an embodiment of a liquid crystal display according to the present invention.

3 is a cross-sectional view taken along line III-III of FIG. 1.

4 is an explanatory diagram for explaining the effect of one embodiment of the present invention.

5 is an explanatory diagram for explaining the effect of one embodiment of the present invention.

6 is a plan view of principal parts showing another embodiment of the liquid crystal display according to the present invention.

7 is an explanatory diagram for explaining the effect of another embodiment of the present invention.

8 is an explanatory diagram for explaining the effect of another embodiment of the present invention.

9 is a plan view showing another embodiment of a liquid crystal display according to the present invention.

<Description of reference numerals for the main parts of the drawings>

1 liquid crystal panel 2 scanning signal line

3: video signal line 4: reference signal line

5: vertical chamber 6: video signal driving circuit

7: Display information processing circuit 8: Clock circuit

9 semiconductor layer 10 pixel electrode

12: protective film 14: alignment film

1A: transparent substrate 3S: source electrode

3D: drain electrode 4A: reference electrode

TFT: Thin Film Transistor Cstg: Capacitive Element

Hereinafter, embodiments of the liquid crystal display according to the present invention will be described in detail with reference to the drawings.

Hereinafter, a first embodiment of the present invention will be described.

In this embodiment, the liquid crystal display device in the case where the liquid crystal interposed between the opposing transparent substrates has positive transmittance anisotropy is used.

Hereinafter, a schematic configuration of the liquid crystal display device will be described.

As shown in Fig. 2, there is a liquid crystal panel 1, and of the transparent substrates arranged between the liquid crystal panels 1 facing each other with the liquid crystal interposed therebetween, the surface of the liquid crystal panel 1A on the liquid crystal side of one transparent substrate 1A. Scan signal lines 2 and reference signal lines 4 extending in the y-direction and arranged in the y-direction are alternately arranged.

In this case, for example, " the reference signal line 4 at the top end, and the next step at a slight distance from the reference signal line 4, and the scan signal line 2 at the next stage, and the scan signal line 2 at the next stage. ), The reference signal lines 4 are arranged repeatedly one after another as in "

In addition, the video signal line 3 is insulated from the scan signal line 2 and the reference signal line 4 in the y direction and parallel to the x direction.

The area in which the unit pixel is formed in each of the rectangular areas covered by the reference signal line 4 and the scan signal line 2 arranged to be kept at a distance from the video signal line 3 disposed adjacent to each other (in the drawing) Dotted line frame A), and each unit pixel disposed on these matrices constitutes a display surface.

The detailed structure of each of these unit pixels is mentioned later.

The liquid crystal display panel 1 is provided with a vertical scanning path 5 and an image signal driving circuit 6 as its external circuits, which are sequentially arranged on each of the scanning signal lines 2 by the vertical scanning path 5. The scan signal (voltage) is supplied, and the video signal is supplied to the video signal line 3 by the video signal driver circuit 6 in accordance with the timing.

Further, the vertical scanning furnace 5 and the image signal driving circuit 6 are configured to be driven by the information from the display information processing circuit 7, in particular, the vertical scanning furnace 5 scans the scanning signals. It is driven through the clock circuit 8 which determines the time.

In addition, the voltage (constant voltage) applied to the reference signal 4 is also supplied from the display information processing circuit 7.

Next, the configuration of the pixel region will be described.

1 is a plan view of a pixel region, and a cross-sectional view relating to II-II thereof is shown in FIG. 3.

As shown in Fig. 1, there is a reference signal line 4 extending in the x direction in the figure on the liquid crystal side of the transparent substrate 1A and a scan signal line 2 spaced apart from the reference signal line by a relatively large distance.

These reference signal lines 4 and the scan signal lines 2 are each made of the same metal material and formed in the same process.

In addition, the reference signal line 4 is formed by integrally forming the reference electrodes 4A arranged in the pixel region.

Accordingly, three reference electrodes 4A are formed in the figure, and are arranged continuously in a direction parallel to the traveling direction of the video signal line 3 described later, and two of them are each of the video signal lines 3, respectively. Is positioned in proximity to the other, and the other one is located at the center of the other two reference electrodes 4A.

As described above, each reference electrode 4A is formed in the shape of a comb teeth with respect to the reference signal line 4. However, in this embodiment, the connection portion of the reference electrode 4A to the reference signal line 4 is connected to the reference signal line 4. The closer to, the wider it is.

In this case, since the liquid crystal used has a positive dielectric anisotropy selected, the wide portion of the reference electrode 4A is configured so that only the portion positioned on the left side with respect to the display electrode 10 becomes wide.

For this reason, as shown in the figure, the reference electrode 4A is formed so as to have an angle ψ between the display electrode 10 located on its right side at the connection portion to the reference signal line 4.

In this case, the angle ψ is set so that an angle smaller than 180 degrees is in a range of 0 ° or more and 90 ° or less among the angles formed in the rubbing direction of the alignment film and the perpendicular line with respect to the bisector of each part.

In addition, the effect by such a structure is mentioned later.

The scanning signal line 2 and the reference signal line 4 (reference electrode) are received on the upper surface of the transparent substrate 1A on which the scan signal line 2 and the reference signal line 4 (reference electrode) are formed. The insulating film 6 (refer FIG. 3) which becomes a film is formed.

Here, the insulating film 6 has a function as an interlayer insulating film for the video signal line 3, which will be described later, of the scan signal line 2 and the reference signal line 4, and as a dielectric for the capacitor Cstg described later. .

The semiconductor layer 8 made of amorphous Si is formed on the insulating film of the lower left portion (the region of the thin film transistor TFT) in the pixel region so as to overlap the scan signal line 2.

By forming a drain electrode and a source electrode on the upper surface of the semiconductor layer 9, a thin film transistor having an inverted staggered structure in which part of the scan signal line 2 is a gate electrode and the insulating film 6 on the gate electrode is a gate insulating film ( The TFTs are formed, but the drain electrodes and the source electrodes are formed so as to be formed at the same time as the video signal lines 3 (to be described later), respectively.

In addition, the semiconductor layer 9 is formed to extend to the intersection region of the scan signal line 2 and the reference signal line 4 with the video signal line 3 described later, and together with the insulating film 6, reliability as an interlayer insulation function. It is supposed to improve.

In the figure, a video signal line 3 extending in the y direction is formed, and a portion thereof continues to form the drain electrode 3D of the thin film transistor TFT.

In this case, the source electrode 3S is also formed at the same time, but the source electrode 3S is formed integrally with the display electrode 10.

The display electrode 10 is shaped like a c-shape, and is first placed so as to travel from the position of the source electrode 3S to the center of the pixel region and the center of the two reference electrodes 4A arranged on the left side thereof. Then, it is formed so as to travel along the reference signal line 4, and to travel in the center of the pixel region and the center of the two reference electrodes 4A disposed on the right side thereof.

In this case, the overlapping portion with the reference signal line 4 of the display electrode 10 constitutes the capacitor Cstg, and the dielectric is the insulating film 6. The capacitor Cstg is provided so that the video signal applied to the display electrode 10 is accumulated for a long time when the thin film transistor TFT is turned off.

In the surface region thus processed, for example, a protective film 12 (see Fig. 3) made of a SiN film or the like is formed, so that deterioration of characteristics due to contact of the liquid crystal with the thin film transistor TFT is avoided.

Moreover, the alignment film 14 is formed in the surface of this protective film 12. As this material, the polyimide resin film is used as the material, for example, the groove | channel parallel to a certain direction according to the characteristic of a liquid crystal is rubbed. It is formed by. Hereinafter, the direction will be referred to as a rubbing direction.

In addition, the part enclosed by the thick line in a figure becomes a substantially pixel area, for example, the block matrix layer opened in the said thick line is formed in the surface of the other transparent substrate which was opposingly arranged.

4 shows a case in which the reference electrode 4A is connected to the reference signal line 4 at an angle of 90 ° with the reference signal line 4 (conventional configuration), and has positive dielectric anisotropy as a characteristic of the liquid crystal. It is a figure which shows the distribution chart of electric field lines (it is shown with the dotted arrow in the figure).

In addition, the drawing shows an electric field line directed from the reference electrode 4A to the display electrode 10, and vice versa.

As shown in the same figure, the electric force lines are generated in the direction perpendicular to each of the electrodes 4A and 10 in parallel, respectively, but their distribution appears different in the vicinity of the reference signal line 4, in particular. That is, the electric force line in the vicinity of the reference signal line 4 indicates an angled portion of the connection portion of the reference electrode 4A with respect to the reference signal line 4 A1 and an angled portion of the display electrode 10 with respect to the reference signal line 4. When it is set to B1, the direction becomes closer to the direction orthogonal to the angles of A1, B1, and B'1. Here, B1 and B'1 are bisectors of the angled portion B1 of the display electrode with respect to the reference signal line.

Here, as shown in the figure, one area of a portion in which the electric field lines are generated in parallel to each of the electrodes 4A and 10 is set to B-1, and the electric field lines are distributed in the vicinity of the reference signal line 4. The motion of each liquid crystal in the case where B-2 is set to one region of the portion where the difference is different will be described.

FIG. 5A is a diagram illustrating the motion of the liquid crystal in the region B-1.

In the drawing, first, the major axis of the liquid crystal molecule PLC is directed in a direction inclined by ø clockwise with respect to the directions D1-D'1 parallel to each of the reference electrode 4A and the display electrode 10.

The direction of this liquid crystal molecule PLC is determined by the rubbing direction of the alignment film 14 formed in direct contact with the liquid crystal.

In this state, when an electric field is applied in the direction of the arrows E˝1-E´1 in the drawing, the liquid crystal molecules PLC are placed on the E˝1-E´1 line by a force that rotates clockwise. The effect of changing the light transmittance of the liquid crystal can be obtained.

5B is an explanatory diagram showing the motion of the liquid crystal in the region B-2.

The liquid crystal in the region B-2 is the same as in the case of FIG. 5 (a) before the electric field is applied, but the electric field is applied in a direction different from that in the case of FIG. In this case, the electric line of force is directed in a direction inclined by 占 + 90 ° clockwise with respect to the directions D1-D'1 parallel to the respective electric fields 4A and 10.

When such an electric field is applied, the liquid crystal molecules PLC act to rotate from F1 to F'1 and to rotate from F1 to F'1.

Thus, each of these forces is balanced with each other, and as a result, the rotational force applied to the liquid crystal molecules PLC becomes 0, and the region B-2 becomes an inactive region in which the effect of changing the light transmittance of the liquid crystal cannot be obtained. Such a non-operation area becomes a spot display defect in the part shown with the oblique line of FIG.

From this, the configuration of the pixel area as described above, i.e., at least the periphery of the connection portion of the reference signal line 4A to the reference signal line 4 opposite to the display electrode 10 is close to the reference signal line 4. It is formed to have a wider width, and the wide portion is configured so that only the portion located on the left side with respect to the display electrode 10 becomes wide, so that the direction of the electric force line in the region B-2 and the vicinity thereof is changed from the region B-1. It is made to be substantially the same as that, and the area | region B-2 and the non-operation area | region regarding this vicinity can be eliminated.

More specifically, by setting the pattern of the reference electrode 4A as described above, the non-operating region of the liquid crystal is formed so that the direction of the electric force line does not coincide with the initial alignment direction of the liquid crystal molecules in the vertical direction but has an angle with respect to the direction. It is avoiding occurrence.

Therefore, as a matter of course, the pattern of the reference electrode 4A is not limited to the above-described pattern as long as it falls within the scope of the above effect.

Hereinafter, a second embodiment of the present invention will be described.

In this embodiment, the liquid crystal display device in the case where the liquid crystal interposed between the opposing projection substrates having negative dielectric anisotropy is used.

The schematic configuration of the liquid crystal display device is the same as that shown in the first embodiment, and the configuration of the display area is only different. That is, FIG. 6 is a view symmetrical to FIG. 1, and the configuration different from that of FIG. 1 is that the wide portion of the reference portion 4A connected to the reference signal line 4 is on the left side of the drawing.

For this reason, as shown in the figure, the reference electrode 4A is formed so as to have an angle ψ between the display electrode 10 located on the left side of the connection portion with respect to the reference signal 4.

In this case, the angle ψ is set such that the angle smaller than 180 ° is within a range of 0 ° to 90 ° in the angle formed between the perpendicular line to the bisector of the angled portion and the rubbing direction of the alignment film.

FIG. 7 shows a case where the reference electrode 4A is connected to the reference signal line 4 at an angle of 90 ° with the reference signal line 4 (conventional configuration), and has negative dielectric anisotropy as a characteristic of the liquid crystal. It is a figure which shows the distribution chart of the electric field lines (shown with the dotted arrow in the figure) concerning.

In addition, the drawing shows the electric field lines directed from the display electrode 10 to the reference electrode 4A, and vice versa, which will be omitted for the sake of brevity. As shown in the figure, the electric field lines have B-3 as one region of a portion occurring in the direction perpendicular to each electrode 10 (4A) in parallel, and the distribution of electric field lines is near the reference signal line 4. The motion of each liquid crystal in the case where one area of the portion which has been changed to B-4 is explained.

First, Fig. 8A is an explanatory diagram showing the movement of liquid crystal in the region B-3.

In the drawing, first, the long axis of the liquid crystal molecule NLC is directed in the direction inclined clockwise by ø with respect to the direction D2-D # 2 parallel to each of the reference electrode 4A and the display electrode 10.

The direction of this liquid crystal molecule NLC is determined by the rubbing direction of the alignment film 14 formed in direct contact with the liquid crystal.

In this state, when an electric field is applied in the direction of the arrows E˝2-E´2 in the drawing, the liquid crystal molecules NLC act to rotate in the counterclockwise direction, and the force to rotate in the direction from E2 to D2 To be authorized. This makes it possible to obtain the effect of changing the light transmittance of the liquid crystal.

Next, FIG. 8B is an explanatory diagram showing the motion of the liquid crystal in the region B-4.

The liquid crystal in the region B-4 is the same as in the case of FIG. 8A before the electric field is applied, but the electric field is applied in a direction different from that in the case of FIG. In this case, the electric line of force is directed in the direction inclined clockwise by ø with respect to the directions D2-D # 2 parallel to the respective electric fields 4A and 10.

As described above, when the directing direction of the long axis of the liquid crystal molecules NLC and the directing direction of the electric force lines are parallel, the rotational force applied to the liquid crystal molecules becomes 0, and the area B-4 changes the light transmittance of the liquid crystal. It becomes a non-operation area which cannot be obtained. Such a non-operation area becomes a bleeding display defect to a portion indicated by diagonal lines in FIG. 7.

As described above, the wider the configuration of the pixel area, that is, the peripheral portion of the side of the connection portion of the reference electrode 4A to the reference signal line 4 that faces the display electrode 10 is closer to the reference signal line 4. And the wide portion is formed so that only the portion located on the right side with respect to the display electrode 10 becomes wide, so that the electric field lines of the region B-4 and its vicinity are almost the same as those of the region B-3. The non-operating area in the area B-4 and its vicinity can be eliminated.

More specifically, by making the pattern of the reference electrode 4A as described above, the non-operating region of the liquid crystal is generated by making the angle of the liquid line not aligned with the initial alignment direction of the liquid crystal molecules, but having an angle with respect to the direction. Can be avoided.

Therefore, it goes without saying that the pattern of the electric force line 4A is not limited to the above-described pattern as long as it includes the above effect.

Hereinafter, a third embodiment of the present invention will be described.

Fig. 9 is a plan view showing another embodiment of the liquid crystal display device according to the present invention, and a liquid crystal display device in the case where a liquid crystal described between transparent substrates arranged oppositely has a positive dielectric anisotropy will be described.

In FIG. 9, unlike in the case of the first and second embodiments, one reference signal line 4 has a pixel column at the top (a pixel column arranged in the x direction in the figure) and a pixel column at the bottom (x in the figure). Pixel columns arranged in the direction of the image).

The pixel column at the upper end and the pixel column at the lower end with the reference signal line 4 are driven by the scan signal line 2 disposed between the reference signal line and the respective pixel column.

As a result, the scan signal lines 2 and the reference signal lines 1 are arranged alternately in the y direction in the drawing, and the area surrounded by the adjacent scan signal lines 2 and the reference signal lines 1 and the adjacent video signal lines 3 are shown. Each pixel area (indicated by a dotted dotted line in the drawing) is configured.

Here, in each pixel area, the configuration different from those of the first and second embodiments only differs from the pattern of the pixel electrode 4A and the pattern of the reference electrode 10, and thus the details will be described below. Explain.

In the drawing, three reference electrodes 10 for each pixel region are provided, and are formed in the pixel region along the y direction in the figure from the reference signal line 4, respectively. In this case, each reference electrode 10 which is continued from the reference signal line 4 is formed so that the end thereof is not connected to the scan signal line 2 but continues to the very front thereof.

The bone of the reference electrode 10 is disposed in close proximity to each video signal line 3 partitioning the pixel region, and the other one is located at the center of the two reference electrodes 10.

Each reference electrode 10 configured as described above includes a reference electrode 10 in the center and a reference electrode 10 located on the right side of the drawing in each pixel region of the pixel column positioned on the upper side with respect to the reference signal line 4. The closer to the reference signal line 4 at the point where the reference signal line 4 is connected, the wider the pixel electrode side on the left side of the drawing. Further, in each pixel area of the pixel column located at the lower side with respect to the reference signal line 4, the reference electrode 10 in the center and the reference electrode 10 located on the left side in the drawing are the reference signal line 4 and The closer the reference signal line 4 is to the connection point, the wider the pixel electrode side on the right side of the drawing.

On the other hand, there is a pixel electrode 4A, and this pixel electrode 4A is a pattern, and each pixel electrode 4A is arranged to be parallel between the three reference electrodes. In this case, the upper and lower ends of the respective pixel electrodes are connected in common by the common connection part 40, and at the same time, the pixel electrode 4A is connected by the common connection part 40 (and the reference signal line 4). And each region between the reference electrode 10 and the reference electrode 10 is configured to be a blocked region.

The pixel electrode 4A configured as described above is connected to the common connection portion 40 in the pixel region of the pixel column located at the upper end side with respect to the reference signal line 4, respectively, in the drawing. Is closer to the width of the reference electrode 4A. The reference on the left side of the drawing is closer to the common connection part 40 in the pixel region of the pixel column positioned at the lower end side with respect to the reference signal line 4, respectively, in the place where the common signal is connected to the common connection part 40 at the lower end part of the drawing. It is comprised so that it may become wide toward the electrode 4A side.

As can be seen from the above-described configuration, the reference electrode 10 and the pixel electrode 4A of the pixel formed on the lower side with the reference signal line 4 as the boundary are formed on the reference electrode 10 of the pixel formed on the upper side. And a pattern in which the relationship between the pixel electrodes 4A and the point symmetry is established.

The common connection portion 40 formed on the pixel electrode 4A formed on the lower end side of the reference signal line 4 is connected to the source electrode of the thin film transistor TFT. The common connecting portion 41 of each pixel electrode 4A on the reference signal line 4 is formed such that a capacitor element Cstg having an insulating film described therebetween as a dielectric film is formed.

The feature of the above-described embodiment is not only the reference electrode 10, but the present invention is also applied to the pixel electrode 4A. As described above, since each pixel electrode 4A is provided with a common connection portion 40 for common connection thereof, the direction of the electric field lines changes between the pixel electrode 4A and the common connection portion 40, and the non-operation area of the liquid crystal is changed. Because this occurs.

In each of the above-described embodiments, the reference signal line 4 (or the common connection unit) is connected to the reference signal line 4 (or the common connection unit 40) of the reference electrode 10 (or the pixel electrode 4A) in any of the above embodiments. The closer to 40) is, the wider the width becomes, thereby making it possible to avoid the inoperation region of the liquid crystal.

However, the reason for such a pattern is that the direction of the electric field lines of the electric field in the vicinity of the connection portion of the reference signal line 4 (or the common connection portion 10) of the reference electrode 10 (or the recovery electrode 4A) is the initial stage of the liquid crystal molecules. It is done to have an angle with respect to the orientation direction or the direction perpendicular to this initial orientation direction.

Therefore, as long as this effect is satisfied, the pattern is not limited to the pattern shown in each embodiment, but it is a matter of course that the pattern is transformed otherwise. Moreover, of course, it applies also when using what has negative dielectric anisotropy as a liquid crystal. In each of the above-described embodiments, the improvement of the reference electrode connected to the reference signal line, and the improvement of the plurality of pixel electrodes connected by the common connection unit on the premise of the improvement are described.

However, only the improvement of the plurality of pixel electrodes connected by the common connection part (that is, no improvement of the reference electrode connected to the reference signal line) is achieved sufficiently. to be.

In this case, although the specific structure is shown in FIG. 9, basically, the direction of the electric field lines of the electric field generated between the common connection part and the reference electrode together with the common connection part is the initial orientation direction or the initial direction of the liquid crystal molecules. It may be configured to have an angle with respect to the direction perpendicular to the orientation direction.

Therefore, in the case where the connection of the pixel electrode to the common connection part is made wider as the common connection part becomes closer, the liquid crystal has a positive dielectric anisotropy or negative dielectric anisotropy, so It goes without saying that the side forming the part is determined.

As in the case of the reference electrode, the closer to the common connection part of the pixel electrode, the smaller the angle between the vertical line with respect to the bisector of the angular portion consisting of the reference electrode of the wide part and the rubbing direction of the alignment film, which is smaller than 180 °. It is preferable that the angle is in the range of 0 ° to 90 °.

As apparent from the above description, according to the liquid crystal display device according to the present invention, the display quality can be improved by eliminating the non-operational region of the liquid crystal generated in the region between the display electrode and the reference electrode.

Claims (10)

Each transparent substrate disposed to face each other with the liquid crystal interposed therebetween, A reference electrode almost perpendicular to the reference signal line provided on the liquid crystal side of one transparent substrate, A pixel electrode disposed in parallel with the reference electrode; A liquid crystal display device comprising a driving circuit for controlling the transmittance of light transmitted between the electrodes by rotating molecules regulated in the initial alignment direction of the liquid crystal by an electric field generated between the pixel electrode and the reference electrode. in, The reference electrode near the connection portion with the reference signal line is configured such that the direction of the electric force line of the electric field generated between the pixel electrode has an acute angle with respect to the initial alignment direction of the liquid crystal molecules or a direction perpendicular to the initial alignment direction. A liquid crystal display device, characterized in that. The method of claim 1, wherein the liquid crystal has positive dielectric anisotropy, And the connection portion of the reference electrode with respect to the reference signal line becomes wider as it approaches the reference signal line, and the wide portion is left of the display electrode as viewed from the liquid crystal side. The method of claim 2, wherein the closer to the reference signal line of the reference electrode, the smaller the width of the angle between the vertical line with respect to the bisector of the angular portion of the angular portion of the display electrode on the right side and the direction of the alignment film. The angle of the side of the liquid crystal display device, characterized in that the range of 0 ° to 90 °. The liquid crystal of claim 1, wherein the liquid crystal has negative dielectric anisotropy, And the connection portion of the reference electrode with respect to the reference signal line becomes wider as it approaches the reference signal line, and the wide portion is on the right side with respect to the display electrode as viewed from the liquid crystal side. The method according to claim 4, wherein the closer to the reference signal line of the reference electrode, the smaller the width of 180 degrees between the vertical line with respect to the bisector of the angular portion composed of the display electrode on the left side and the angular portion of the display electrode on the left side. The angle of the liquid crystal display device, characterized in that the range of 0 ° to 90 °. The pixel electrode is provided in plural, and a common connection portion for connecting each pixel electrode in common is provided, and the pixel electrode is provided with the common connection portion in the vicinity of the connection portion with the common connection portion. And the direction of the electric force lines of the electric field generated between the reference electrode and an acute angle with respect to the initial alignment direction of the liquid crystal molecules or a direction perpendicular to the initial alignment direction. A pixel electrode and a reference electrode are formed in each pixel region of one side of the liquid crystal side in each of the transparent substrates arranged to face each other with the liquid crystal interposed therebetween, In a liquid crystal display device for controlling the transmittance of light transmitted between the electrodes by generating a rotational twist on the molecules regulated in the initial alignment direction of the liquid crystal by the electric field generated between the pixel electrode and the reference electrode, A plurality of pixel electrodes are provided, and the pixel electrodes are connected by a common connection unit. The direction of the electric field of the electric field generated between the common connecting portion and the reference electrode in the vicinity of the common connecting portion is configured to have an acute angle with respect to the initial alignment direction of the liquid crystal molecules or the direction perpendicular to the initial alignment direction. There is a liquid crystal display device. A transparent substrate disposed to face each other so as to sandwich the liquid crystal; A reference electrode supplied with a reference signal through the reference signal line, in the reference electrode substantially perpendicular to the reference signal line; In the liquid crystal display device comprising a pixel electrode arranged in parallel to the reference electrode, And the direction of the boundary line of the reference electrode in the vicinity of the reference signal line is inclined to form an acute angle with an electric field direction generated between the pixel electrode and the reference electrode in a portion parallel to the pixel electrode. 9. The pixel electrode according to claim 8, wherein a plurality of the pixel electrodes are provided in one pixel, and common pixel electrodes are formed to interconnect each pixel electrode, and the direction of the boundary line of the pixel electrode in the vicinity of the common pixel electrode is the direction of the electric field. A liquid crystal display device characterized by being inclined at an acute angle. 9. The pixel electrode according to claim 8, wherein a plurality of the pixel electrodes are provided in one pixel, and common pixel electrodes interconnecting respective pixel electrodes are provided, and boundary lines of the pixel electrodes in the vicinity of the common pixel electrode are formed in the vicinity of the reference signal line. A liquid crystal display device, characterized in that parallel to the boundary line of the reference electrode.