JP2001083522A - Liquid crystal display device and thin film transistor substrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the response characteristics of a liquid crystal display device and to increase the production yield. SOLUTION: The device is a vertical alignment type one in winch the alignment of the liquid crystal while voltage is applied is controlled by forming a linear structure consisting of a plurality of structural units or linear slits in at least one of a pair of substrates 1, 12 having electrodes. In this method, an alignment controlling means (connecting part 30e) to form the characteristic point of alignment satisfying s=-1 of the liquid crystal molecules is disposed in the part where the structure on the pixel electrode 30 or the slit 30a in the aforementioned electrode crosses with the edge of the pixel electrode 30 on one substrate 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a liquid crystal display (L).
More specifically, the present invention relates to a VA type liquid crystal display device and a thin film transistor substrate.

[0002]

2. Description of the Related Art In recent years, the technology of manufacturing a TN type TFT-LCD has progressed in each step, and the contrast and the front face have been improved.
The color reproducibility has surpassed that of the CRT. However, a TN (twisted nematic) -LCD has a major drawback of a narrow viewing angle, and thus has a problem that its use is limited.

FIGS. 1 (a) to 1 (c) are diagrams for explaining this problem. FIG. 1A shows a state in which white is displayed without applying a voltage between the two electrodes 101 and 102, and FIG.
FIG. 1C shows a state in which an intermediate potential V ₁ is applied between the two electrodes 101 and 102 to display a halftone. FIG. 1C shows a state where a predetermined voltage V ₂ is applied between the two electrodes 101 and 102. In a state where black is displayed.

FIGS. 1A to 1C show two electrodes 10.
Alignment films 103 and 104 are formed on the opposing surfaces of the substrates 1 and 102 so that the alignment directions are different from each other by 90 degrees. Also,
Although not shown, a polarizing plate is disposed outside each of the two electrodes 101 and 102 in a state where the linear polarization directions are twisted by 90 degrees with respect to each other. 1 (a) to 1
The liquid crystal molecules L shown in (c) are twisted according to the alignment direction of the alignment films 103 and 104, but are shown here without considering twist for convenience.

By the way, when no voltage is applied as shown in FIG. 1A, the liquid crystal molecules L are oriented in the same direction with a slight inclination angle (about 1 ° to 5 °). In this state, it looks almost white in any direction. FIG.
In the state where the voltage V ₂ is applied as shown in (c), the intermediate liquid crystal molecules L excluding the vicinity of the surfaces of the alignment films 103 and 104 are removed.
Are oriented in the vertical direction, and the incident linearly polarized light is blocked by the polarizing plate, so that it looks black from the outside. At this time, the light obliquely incident on one of the electrodes 101 passes obliquely to the direction of the liquid crystal molecules aligned in the vertical direction, so that the deflection direction is twisted to some extent. It looks half-tone (gray).

Further, as shown in FIG. 1B, FIG.
In a state where the application of a low intermediate voltages V ₁ from the state, the liquid crystal molecules in the vicinity of the alignment films 103 and 104 is also oriented in the horizontal direction, the liquid crystal molecules L rises obliquely in the middle of the cell. Therefore, the birefringence of the liquid crystal is somewhat lost, the transmittance is reduced, and a halftone (gray) display is obtained. However, this can only be applied to light that is perpendicularly incident on the liquid crystal panel, and is different when light is obliquely incident on the surface of one electrode 101, that is, when viewed from the left and right directions in the figure.

That is, in FIG. 1B, the direction of the liquid crystal molecules L is parallel to the light from the lower right to the upper left. Therefore, the liquid crystal hardly exhibits a birefringence effect, and therefore looks black when viewed from the left side. On the other hand, since the direction of the liquid crystal molecules L is perpendicular to the light traveling from the lower left to the upper right, the liquid crystal molecules L exert a large birefringence effect on the incident light, and the incident light is twisted. So it will be seen in a color close to white. That is, in FIG. 1B, the display intensity changes depending on the viewing angle.
Is the biggest drawback.

Accordingly, as a method of improving the viewing angle characteristics without lowering the response speed, a VA (Ve
(rtically aligned) schemes have been proposed. Fig. 2 (a)-
FIG. 2C is a diagram for explaining the VA method. The VA method is a method in which a negative liquid crystal material and a vertical alignment film are combined. First, as shown in FIG. 2 (a), when no voltage is applied, the liquid crystal molecules are oriented in the vertical direction to display black. Note that V
In the A method, the alignment films 103 and 104 are subjected to a vertical alignment process.

When a predetermined voltage is applied between the two electrodes 101 and 102 as shown in FIG.
Are oriented in the horizontal direction and become white display. VA method is TN
Compared with the system, the display contrast is high, the response speed is fast, and the visual characteristics in white display and black display are good. Further, as shown in FIG. 2B, when a smaller voltage is applied between the two electrodes 101 and 102 than in the case of white display, the liquid crystal molecules L are oriented in an oblique direction. In this case, light in the direction perpendicular to the surface of the electrode 101 is displayed as halftone on the display panel. However, in FIG.
The liquid crystal molecules L are parallel to light traveling from the lower right to the upper left. Therefore, since the liquid crystal molecules L hardly exhibit the birefringence effect, they appear black when viewed from the left side. On the other hand, since the liquid crystal molecules L are perpendicular to the light traveling from the lower left to the upper right, the liquid crystal molecules L exhibit a large birefringence effect with respect to the incident light, and the incident light is twisted. The display becomes similar to.

As described above, in the VA mode, even when no voltage is applied, the liquid crystal molecules in the vicinity of the alignment film are almost vertical. Therefore, the contrast is higher in each step than in the TN mode, and the viewing angle characteristics are excellent. However, when halftone display is performed in the VA system, there is a problem similar to that in the TN system in which the display intensity changes when the viewing angle is changed, and the viewing angle characteristics are still insufficient.

The present applicant uses a conventional vertical alignment, encloses a so-called negative type liquid crystal having a negative dielectric anisotropy as a liquid crystal material between electrodes, so that the tilt direction of liquid crystal molecules when voltage is applied is one. Japanese Patent Application No. 10-185836 discloses a configuration in which a domain regulating means for regulating differently in a plurality of regions in a pixel is provided. FIGS. 3 (a) to 3 (c) show that a slit S is formed on the electrode 111 of one pixel on the first substrate side as a domain regulating means.
FIG. 9 is a diagram illustrating the principle of improving visual characteristics by orientation division in a case where a structure in which a projection P is provided within one pixel on the electrode 112 on the second substrate side is adopted.

As shown in FIG. 3A, when no voltage is applied, the liquid crystal molecules L are oriented perpendicular to the substrate surface. In addition, as shown in FIG.
When a predetermined voltage is applied between 1,112, the liquid crystal molecules L
Is substantially horizontal with respect to the substrate surface to obtain a white display.
Further, as shown in FIG.
When the voltage is applied between 1 and 112, an electric field oblique to the substrate surface is generated at the slit S (electrode edge portion) S. Further, the liquid crystal molecules L near the surface of the projection P slightly tilt from the state where no voltage is applied. The inclination direction of the liquid crystal molecules L is determined by the inclined surface of the projection P and the influence of the oblique electric field, and the orientation direction of the liquid crystal molecules 113 is divided in the middle of the projection P and the middle of the slit 111s.

At this time, for example, light transmitted from directly below the substrate to immediately above the substrate is slightly affected by the birefringence because the liquid crystal molecules L are slightly inclined, so that transmission is suppressed, and gray halftone display is performed. can get. Light transmitted from the lower right to the upper left is hardly transmitted in a region where the liquid crystal molecules L are tilted to the left, but is very easily transmitted in a region where the liquid crystal molecules L are tilted to the right. A tone display is obtained. Light transmitted from the lower left to the upper right is also displayed in gray according to the same principle. Thereby, a uniform halftone display can be obtained in all directions of one pixel.

Therefore, in FIG. 3B, in all of the display states of black, halftone, and white, good display with little viewing angle dependence can be obtained. 3 (a) to 3 (c), a slit is provided in one pixel of the electrode 111 on the first substrate side as a domain regulating means, and one pixel is formed on the electrode 112 on the second substrate side. Although the projection 20 is provided, it can be realized by other means. The new VA method is described below as MVA (multi-domai
n vertical alignment) method.

FIGS. 4 (a) to 4 (c) are diagrams showing an example of realizing the domain restriction means. FIG. 4 (a) shows an example of realizing only the electrode shape, FIG. 4 (b) shows an example of devising the substrate surface shape, and FIG. 4 (c) devises the electrode shape and the substrate surface shape. Here is an example. Each of these examples is shown in FIG.
Although the orientation shown in FIG. 3 (c) is obtained, each structure is slightly different.

Next, the opposition of the two substrates shown in FIG.
An example in which a projection is provided on a surface will be described. Fig. 4 (b)
, Electrodes 111 and 112 on the opposing surfaces of the two substrates
On the top, there are projections P for alternately dividing the orientation direction.
₁, P_TwoAre formed and hang on their inner surfaces
Direct alignment films 113 and 114 are provided. Vertical alignment film
Has been subjected to a vertical alignment treatment. Injection between two substrates
The liquid crystal is a negative type. When no voltage is applied,
On the alignment film, the liquid crystal molecules L are aligned perpendicular to the substrate surface.
You. Protrusion P₁, P_TwoLiquid crystal molecules L are perpendicular to the slope
The projection P₁, P_TwoLiquid crystal molecule L on
Tilts. However, when no voltage is applied, the protrusion P ₁, P
_TwoIn most parts of the region except for, the liquid crystal molecules L
As shown in FIG.
And a good black display is obtained.

When a voltage is applied, the liquid crystal molecules L are projected P ₁ ,
Although the portion without P ₂ is parallel to the substrate (electric field perpendicular to the substrate), inclined in the vicinity of the projection P _1, P _2. That is, when a voltage is applied, the liquid crystal molecules L incline according to the strength of the electric field. However, when the electric field is in a direction perpendicular to the substrate and the inclination direction is not defined by rubbing, the azimuth inclining with respect to the electric field Can have all directions of 360 °. Protrusion P
₁ and P ₂ , the electric field is inclined in a direction parallel to the slopes of the projections P ₁ and P _{2. When} a voltage is applied, the liquid crystal molecules L are inclined in a direction perpendicular to the electric field. _1, P ₂
Thus, the orientation is originally coincident with the inclined direction, and the orientation becomes more stable. Thus, the projections P ₁ ,
P ₂ has obtained a stable orientation by the effects of both the inclination and the electric field of the slope. Further, when a strong voltage is applied, the liquid crystal molecules L become substantially parallel to the substrate.

As described above, the projections P ₁ and P ₂ serve as triggers for determining the orientation of the liquid crystal molecules L when voltage is applied. In FIG. 4A, slits S ₁ and S ₂ are provided in both or one of the electrodes 111 and 112. The alignment films 113 and 114 are subjected to a vertical alignment process,
A negative liquid crystal is sealed between the substrates. When no voltage is applied, the liquid crystal molecules are oriented perpendicular to the substrate surface.
When a voltage is applied, slits (electrode edge portions) S ₁ , S ₂
As a result, an electric field is generated in a direction oblique to the substrate surface. The tilt direction of the liquid crystal molecules L is determined by the effect of this oblique electric field,
As shown in the figure, the alignment direction of the liquid crystal is divided into the left and right directions.

FIG. 4C shows an example in which the methods shown in FIGS. 4A and 4B are combined. One electrode 111 has a slit S formed thereon, and the other electrode 112 has a slit S formed thereon. A projection P is provided. The example in which the three domain restriction means are realized has been described above, but various modifications are possible.

FIG. 5 is a plan view showing an arrangement relationship among bus lines, projections, pixels, and electrodes in a liquid crystal display panel which is divided into four directions. FIG. 6 is a sectional view taken along line II of FIG. is there. 5 and 6, a plurality of gate bus lines 122 extending in the X direction (horizontal direction in the drawing) are formed on the TFT substrate 121 at intervals in the Y direction (vertical direction in the drawing). . Further, between each gate bus line 122, a capacitance bus line 123 extending in the X direction is formed. From the capacitance bus line 123, the auxiliary capacitance branch line 12 is opposed to a part of a drain bus line described later.
3a is formed in the Y direction with such a length as not to contact the gate bus line 122.

The gate bus line 122 and the capacitance bus line 123 are covered with a first insulating film 124. Further, a plurality of drain bus lines 125 extending in the Y direction are formed on the first insulating film 124 at intervals in the X direction. A TFT (thin film transistor) 126 is formed at an intersection of the gate bus line 122 and the drain bus line 125. TFT12
6 denotes a gate bus line 12 via the first insulating film 124.
5, a semiconductor layer 126a formed on
and a source electrode 126s formed on the semiconductor layer 126a. The drain electrode 126d is connected to a nearby drain bus line 125. Drain bus line 125
And the TFT 126 are covered with the second insulating film 127.

A pixel electrode 128 made of ITO is formed on the second insulating film 127 in a region surrounded by the two drain bus lines 125 and the two gate bus lines 122. The pixel electrode 128 is the second
Source electrode 1 through a hole (not shown) of insulating film 127;
26s. The potential of the capacitance bus line 123 is fixed to an arbitrary magnitude. When the potential of the drain bus line 125 fluctuates, the potential of the pixel electrode 128 fluctuates due to capacitive coupling caused by stray capacitance. In the configuration of FIG. 6, the pixel electrode 128 is connected to the capacitance electrode 12 via the auxiliary capacitance.
3, the potential fluctuation of the pixel electrode 128 can be reduced.

In FIG. 6, a color filter 132, a black matrix 133, a common electrode 134, and an alignment film 135 are sequentially formed on a counter substrate 131 facing the TFT substrate 121. Also, protrusions 130 and 13 having a zigzag bending pattern extending in the Y direction are provided on opposing surfaces of the opposing substrate 131 and the TFT substrate 121, respectively.
6 are formed. The bending angle of the bending pattern is approximately 90 degrees.

The protrusions 130 on the TFT substrate 121 side are arranged at equal intervals in the X direction, and the bending point is disposed substantially at the center of the gate bus line 122. Counter substrate 1
The protrusions 136 on the 31st side have a pattern of substantially the same shape as the protrusions 130 on the TFT substrate 121 side, and
It is formed on the common electrode 134 so as to be located substantially at the center between the plurality of protrusions 130 of the T substrate 121.

The projections 130 and the pixel electrodes 128 on the TFT substrate 121 side are covered with an alignment film 129, and the projections 136 on the counter substrate 131 side are also covered with another alignment film 135. The protrusion 130 on the TFT substrate 121 side and the counter substrate 13
The protrusions 136 on one side each intersect the edge of the pixel electrode 128 at an angle of 45 degrees. Further, a polarizing plate (not shown) is disposed on each of the surfaces of the TFT substrate 121 and the counter substrate 131 that do not sandwich the liquid crystal material 139. The polarizers are arranged such that their deflection axes intersect at 45 degrees at the angle linear portion of the projection 130.136 and cross Nicol. That is, the deflection axis of one polarizing plate is parallel to the X direction in the figure, and the other deflection axis is parallel to the Y direction in the figure.

The TFT substrate 121 and the counter substrate 131 are arranged in parallel at a certain interval from each other, and the gap therebetween is filled with a liquid crystal material 139. Liquid crystal material 139
As described above, those having a negative dielectric anisotropy are employed. The projections 130 and 136 are made of the liquid crystal material 13.
9 is formed from a material having a dielectric constant equal to or lower than the dielectric constant of No. 9.

Next, the orientation of the liquid crystal molecules L when an intermediate voltage is applied to the pixel electrode will be described with reference to an example in which a slit is provided in the pixel electrode. FIG. 7 is a cross-sectional view of a TFT having a slit S in a pixel electrode instead of the protrusion 130 shown in FIG.
A gate bus line, a drain bus line on the FT substrate,
FIG. 3 is a plan view showing an arrangement relationship between a capacitance bus line and a pixel electrode 128.

In FIG. 7, the pixel electrode 128a is divided into a plurality of regions by a plurality of slits S passing between upper protrusions 136a. These regions are connected to each other by a connecting portion 128b crossing each slit S. The two slits S near the center of the pixel electrode 128a cross each other at the edge of the pixel electrode 128a.

Then, assume that an intermediate voltage is applied to the pixel electrode 128a. The liquid crystal molecules L on the pixel electrode 128a are inclined with respect to the surface of the pixel electrode 128a. In FIG. 7, the liquid crystal molecules L are indicated by cones, and the sharp portions indicate the position of one end of the liquid crystal molecules on the TFT substrate side, and the circular surface of the cone indicates the position of the other end on the counter substrate side. The tilt directions of the liquid crystal molecules L are four types according to the principle shown in FIG.

As described above, the MVA method is a method in which a liquid crystal having a negative dielectric anisotropy is oriented almost perpendicularly to the substrate surface, has a high contrast and does not lower the switching speed. Since the visual characteristics can be improved, the display quality is good. In addition, the use of the domain control means can further improve the viewing angle characteristics.

[0031]

The MVA type liquid crystal display device can realize high image quality, high reliability and high productivity. However, since the VA method is originally weakly anchored as compared with the horizontal alignment type such as the TN method, it has a property of being easily affected by an electric field, and the MVA method inherits such a property.

Therefore, as shown in FIGS. 8A and 8B, the alignment state of the liquid crystal molecules L around the pixel electrode 128 is caused by the fluctuation of the potential Egc of the gate bus line and the potential (data voltage) Egs of the drain bus line. May change. Such a phenomenon similarly occurs in the case of the TN method,
It is considered that the VA method is more likely to occur than the N method.
Further, as a phenomenon peculiar to the MVA method, a projection may be charged by driving or other various conditions. At this time, the liquid crystal alignment at a portion that intersects the drain bus line and the gate bus line also changes due to the influence of the charging of the protrusion.

When the orientation around the pixel changes, the stray capacitance, for example, the capacitance Cgc between the gate and the common electrode, the capacitance Cgs between the gate and the source, and the capacitance Cdc between the drain and the common electrode.
Etc. also change. As a result, the potential of the pixel electrode 126s also fluctuates due to capacitive coupling. Normally, the potential fluctuation of the pixel electrode is reduced by the auxiliary capacitance, but it may not be completely compensated. In particular, this is likely to occur when the auxiliary capacitance is reduced to increase the aperture ratio. When the pixel electrode potential fluctuates, flicker called flicker occurs on the screen.

Although there is a means for increasing the auxiliary capacitance to such an extent that the fluctuation of the pixel electrode potential is completely eliminated, the aperture ratio is reduced accordingly. Next, generation of an afterimage in the MVA liquid crystal display device will be described. The occurrence of an afterimage in the liquid crystal display device is caused by an abnormal response speed. This occurs because the domain control direction is not determined on the above-mentioned protrusion or slit on the electrode.

The instability in the domain control direction is caused by a variation in cell thickness and the like, and a liquid crystal display device that causes an afterimage is not shipped as a defective product. As a result of investigating the cause of the occurrence of an afterimage that remains for a long time, the following became clear. That is, in a liquid crystal display device employing a structure in which a plurality of protrusions or slits are formed in an electrode, FIG.
As shown in (a) and (b), when there is a difference between the domain state when the display is changed from black to white and the domain state when the display is changed from halftone to white, It has been found that an afterimage that remains for a long time occurs.

In FIG. 9A, the number of domains on the slit S after the display is changed from black to white is determined by the pixel electrode 12.
8a, and there are six pieces divided by the middle of all the connecting portions 128b and the connecting portion 128b. This allows
The liquid crystal molecules L near the slit S are aligned in a direction perpendicular to the linear portion of the slit S. On the other hand, in FIG. 9B, the slit S after changing the display in the order of black, halftone, and white.
The upper number of domains is two or four divided by a part of the connecting portion 128b. As a result, there is a region where the domain does not change from the connecting portion 128b to the middle of the connecting portion 128b. In this region, the liquid crystal molecules L near the slit S are obliquely aligned with respect to the linear portion of the slit S.

One of the causes is that in the halftone display, a voltage is not sufficiently applied to the liquid crystal molecules L on the protrusions 130 or the slits S, and the liquid crystal molecules L are moved with respect to the substrate surface as shown in FIG. It is in a substantially vertical state, and the influence of the electric field at the edge of the pixel electrode 128a and the orientation of the display domain affected by the electric field extends to the portion where the alignment control means is divided by the joint portion, and the alignment control means is divided. It is considered that the effect of controlling the orientation due to the above does not function sufficiently. That is, at the time of the intermediate display, the slit S or the protrusion 130
When the liquid crystal molecules L in the vertical direction are in a vertical state, the liquid crystal molecules L in the vicinity thereof are tilted with respect to the linear portion of the slit S or the projection 130 under the influence of the electric field at the edge of the pixel electrode 128a.

Thus, when the display shifts from the halftone display to the white display, the domain shown in FIG. 9A disappears and the domain is connected, and then the domain disappears and the domain is connected. As a result, as shown in FIG. 9 (b), the domains facing the upper right are connected to each other and the domain facing the lower left disappears, and the domains on the slit S after the white display are reduced to two. Become.

As another cause of the occurrence of an afterimage, it is conceivable that the projection 130 of the alignment control means or the bent portion of the pattern of the slit S is arranged at the edge of the pixel electrode 128a. The alignment state of the liquid crystal molecules L at the bent portion is any one of the three types shown in FIGS. 11 (a) to 11 (c).
However, due to the influence of the orientation due to the edge of the pixel electrode 128a, the orientation at the bent portion is in the state shown in FIG. 11 (c). As a result, as shown by the dashed line in FIG. The alignment control direction by the edge of 128a spreads in the pixel. It is considered that this influences the orientation of the domain on the slit S particularly in the case of the halftone display, so that the orientation control effect by dividing the orientation control means does not function sufficiently.

In the TFT substrate, a region where a plurality of electrodes are stacked, in particular, a pixel electrode 128a and a capacitor electrode (capacitor bus line) 123 are arranged as shown in FIGS. 13 (a) and 13 (b). A short circuit may occur through the insulating film between them. At this time, the slit S
In a liquid crystal display device having a structure in which a pixel electrode 128a is divided into a plurality of regions by using a liquid crystal display and the regions are electrically connected by connecting portions 128b, X in FIGS. 13A and 13B is used.
As shown by, by cutting the connecting portion 128b near the TFT 126 in the region of the pixel electrode 128a that is short-circuited with the capacitor bus line 218, the short-circuited region is separated from other regions, and the liquid crystal molecules in the pixel are separated. It can be partially driven.

However, since the region of the pixel electrode 128a that is short-circuited to the capacitance bus line 123 exists at the center of the pixel, as shown by the dashed line in FIG. Only the following area can be driven, and this pixel region becomes a point defect and lowers the yield of the device. An object of the present invention is to provide a liquid crystal display device capable of reducing a fluctuation in potential of a pixel electrode and reducing flicker without changing the size of an auxiliary capacitor.

Another object of the present invention is to provide a liquid crystal display device and a thin film transistor substrate which can improve the response characteristics and the production yield.

[0043]

Means for Solving the Problems (1) The above-mentioned problems are:
As illustrated in FIG. 24, at least one of a pair of substrates having electrodes is provided with a linear structure or a linear slit composed of a plurality of constituent units to control a liquid crystal alignment at the time of voltage application. In the liquid crystal display device, the liquid crystal molecules are aligned at a portion where the slit in the structure or the electrode and the edge of the pixel electrode on one of the substrates intersect to form an alignment singular point of s = -1. The problem is solved by a liquid crystal display device provided with control means.

Further, the above-mentioned problem is caused by at least one of a pair of substrates having electrodes as shown in FIG.
In a vertical alignment type liquid crystal display device in which a linear structure composed of a plurality of constituent units or a linear slit is provided to control liquid crystal alignment when voltage is applied, the structure or the structure formed on one of the substrates A liquid crystal display characterized in that an alignment control means for forming an alignment singular point where liquid crystal molecules are s = + 1 is arranged at a portion where a slit and an edge of a pixel electrode formed on the other side of the substrate intersect. Solved by the device.

Further, the above-described problem is caused by at least one of a pair of substrates having electrodes as illustrated in FIG.
In a vertical alignment type liquid crystal display device in which a linear structure or a linear slit including a plurality of constituent units having a bent portion is provided to control liquid crystal alignment when voltage is applied, one of the substrates having a pixel electrode The liquid crystal display device is characterized in that the bent portion of the upper structure or the slit is off the edge of the pixel electrode.

Further, the above-mentioned problem is caused by at least one of a pair of substrates having electrodes as shown in FIG.
In a vertical alignment type liquid crystal display device in which a linear structure or a linear slit including a plurality of constituent units having a bent portion is provided to control liquid crystal alignment when voltage is applied, the pixel on one of the substrates The liquid crystal display device is characterized in that the bent portion of the structure or the slit disposed on the other substrate facing the electrode is not disposed on the edge of the pixel electrode.

Further, as illustrated in FIG. 30, the above-described problems are caused by a storage capacitor forming electrode formed on a first substrate, an active element formed on the first substrate, and an active element formed on the first substrate. A pixel electrode connected to the element and formed on the first substrate and divided into at least three regions by a slit, wherein one region of the three regions of the pixel electrode is different from another region The electrical connection to the thin-film transistor substrate has a plurality of different routes in the region through which the thin film transistor substrate passes.

The above-mentioned problem is solved by a liquid crystal display device having the thin film transistor substrate. The above-mentioned problem is solved by any one of the liquid crystal display devices having the thin film transistor substrate. Next, the operation of the present invention will be described.

According to the present invention, in a liquid crystal display device having at least one of a structure on an electrode used as a domain regulating means and a slit in the electrode, an extension of the structure or the slit intersects the edge of the pixel electrode. In the vicinity of the portion, a liquid crystal layer forms an orientation singularity such that s = -1 or s = + 1. The change of the domain on the slit when the liquid crystal molecules are applied to the present invention is shown in FIG.
As shown in (a), when the display is changed from black display to white display, the number of domains on the slit divided by the connecting portion is eight. According to FIG. 31 (a),
The number of domains increases as compared with FIG. 9A showing the prior art. This is because a singular point of the orientation vector of s = -1 is formed at the edge of the pixel electrode. When the display changes from black display to white display through halftone display, FIG.
As shown in (b), the domain connected to the domain disappears. That is, the domain change on the slit is suppressed to a very small level near the edge of the pixel electrode as compared with FIG. 9A.

As a result, the difference in the domain state between white when responding from black display to white display and white when responding to white from halftone display can be reduced to an inconspicuous level. The change can be reduced to a level that cannot be recognized as an afterimage. According to the present invention, a high effect can be obtained only when the orientation control means is applied in combination with a panel formed from a plurality of constituent units. Simply providing a domain control means on a structure or a slit only at the edge of the pixel electrode cannot control the domain near the center of the pixel electrode, resulting in an afterimage. Further, in the white response from the halftone display, since the control means of the edge of the pixel electrode becomes ineffective,
In the pixel electrode, the structure or the domain on the slit cannot be controlled at all, and an afterimage occurs.

Further, in the present invention, the influence of the electric field due to the edge of the pixel electrode on the bent portion is eliminated. Therefore, in the vicinity of the pixel electrode edge, an alignment state different from the original alignment control of the structure or the slit is generated. Can be reduced, the afterimage can be eliminated. Further, in the present invention, two systems are provided as an electrical connection path of the pixel electrode, a path through a region where a storage capacitor forming electrode and a capacitor are formed, and a path not through. As a result, when an electrical short circuit occurs between the storage capacitor forming electrode and the pixel electrode, the liquid crystal molecules can be driven in the other region by electrically disconnecting the region forming the capacitor from the other region. Area. This pixel has slightly different display characteristics than the normal case where the short circuit does not occur.
Clearing the display defect standard is a certain difference in the characteristics depending on the number and locations, so that the yield of the TFT substrate can be improved. (2) As described above, as shown in FIGS. 14 to 22, a liquid crystal having a negative dielectric anisotropy between a first substrate and a second substrate having a vertical alignment treatment applied to the substrate surface. In the liquid crystal display device, the orientation of the liquid crystal is substantially vertical when no voltage is applied, becomes almost horizontal when a predetermined voltage is applied, and becomes oblique when a voltage smaller than the predetermined voltage is applied. A first domain regulating means provided on the first substrate for regulating an alignment direction in which the liquid crystal is inclined when a voltage smaller than the predetermined voltage is applied, and a first domain regulating means provided on the second substrate, A second domain regulating unit that regulates an alignment direction in which the liquid crystal becomes oblique when a voltage smaller than the voltage is applied, and the first domain regulating unit is provided at least on an electrode of the first substrate. , The first The projection of the dielectric protruding towards the liquid crystal layer to a part of the contact surface between the liquid crystal plate on the slope,
A plurality of first bus lines formed at intervals on a surface of the first substrate or the second substrate that sandwiches the liquid crystal, intersecting the first bus line; A plurality of second bus lines formed at intervals above the first bus line; and pixels formed in a region defined by the first bus line and the second bus line. An electrode, a portion corresponding to at least a part of a region between the pixel electrode and the first bus line,
The problem is solved by a liquid crystal display device having a dielectric structure different from the protrusion formed on at least one of the first substrate and the second substrate.

Next, the operation of the present invention will be described. According to the present invention, the gate bus lines (the first
The dielectric structure was disposed in a region between the pixel electrode and the region between the drain bus line (second bus line) and the pixel electrode. This allows the dielectric constant between the pixel electrode and the bus line to be fixed by the dielectric structure, so that the variation in stray capacitance between them is suppressed.

Further, since the dielectric structure is also formed on the bus line, the liquid crystal layer on the dielectric structure is thinned, and the liquid crystal molecules of the liquid crystal layer are less likely to move from the vertical orientation. Even if the applied voltage changes, the liquid crystal molecules hardly tilt, and the fluctuation of the stray capacitance becomes very small. In addition, the stray capacitance above the bus line has a large component fixed by the dielectric structure, so that the fluctuation of the stray capacitance is reduced.

As described above, when the fluctuation of the stray capacitance is suppressed, the pixel potential becomes constant and the occurrence of flicker is prevented. In addition, it is possible to increase the aperture ratio by reducing the width of the capacitance bus line for suppressing the fluctuation of the capacitance.

[0055]

Embodiments of the present invention will be described below with reference to the drawings. (First Embodiment) FIG. 14 shows a planar state of a TFT substrate excluding an insulating film and a dielectric protrusion of one pixel of an MVA type liquid crystal display device according to a first embodiment of the present invention.
FIG. 15 is a plan view showing a state where dielectric protrusions are formed on the TFT substrate shown in FIG. FIG.
FIG. 17 is a sectional view taken along the line III-III in FIG.
FIG. 18 is a sectional view taken along line IV-IV of FIG.

In FIG. 14, a first TFT on which a TFT is formed is shown.
A plurality of gate bus lines 2 extending in the X direction (horizontal direction in the figure) are formed on the glass substrate (TFT substrate) 1 at an interval in the Y direction (vertical direction in the figure). Also,
Between each gate bus line 2, a capacitor bus line (storage capacitor forming electrode) 3 extending in the X direction is formed.
From the capacitance bus line 3, an auxiliary capacitance branch line 3 a facing a part of a drain bus line described later extends in the Y direction with a length that does not contact the gate bus line 2.

The gate bus line 2, the capacitance bus line 3, and the auxiliary capacitance branch line 3a are formed simultaneously. That is, an aluminum film having a thickness of 100 nm and a titanium film having a thickness of 50 nm are formed on the first glass substrate 1 by sputtering, and then these films are patterned by photolithography to form the gate bus line 2 and the capacitor. The bus line 3 and the auxiliary capacitance branch line 3a are formed. For the patterning, a reactive ion etching (RIE) method using a mixed gas of BCl ₃ and Cl ₂ is used.

Gate bus line 2 and capacitance bus line 3
Is, as shown in FIG. 16, a 400 nm-thick film formed by plasma-enhanced chemical vapor deposition (PE-CVD).
A plurality of drain bus lines 5 extending in the Y direction are formed on the gate insulating film 4 at intervals in the X direction.

In the vicinity of the intersection between the gate bus line 2 and the drain bus line 5, a TFT (thin film transistor) 6 is formed as an active element. The TFT 6 is
As shown in FIG. 17, an active layer 6a formed via a gate insulating film 4 in a region straddling a part of the gate bus line 5
And a drain electrode 6d formed on the active layer 6a on one side of the gate bus line 5, and a source electrode 6s formed on the active layer 6a on the other side of the gate bus line 5. The drain electrode 6d is connected to the nearby drain bus line 5.

The drain electrode 6d and the source electrode 6s are separated on a channel protective film 6b formed on the channel region of the active layer 6a. The channel protective film 6b
Is formed by the following method. That is, a silicon nitride film is formed on the active layer 6a and the gate insulating film 4 by PE-
After a silicon nitride film is formed to a thickness of 140 nm by a CVD method, a photoresist (photosensitive resin) is applied on the silicon nitride film. Then, the photoresist is exposed and developed to form a resist pattern. The exposure process includes a first exposure step of irradiating the photoresist with exposure light from the lower surface of the glass substrate 1 using the gate bus line 2 as an exposure mask, and a photolithography process from the upper surface of the glass substrate 1 using a normal exposure mask. A second exposure step of irradiating the resist with exposure light. Thus, the edge of the resist pattern is defined by the edge of the gate bus line 5. When the silicon nitride film in a region not covered with such a resist pattern is etched by a wet method using buffered hydrofluoric acid or an RIE method using a hydrofluoric acid-based gas, a channel protective film 6b made of a silicon nitride film is formed. Will be done.

The active layer 6a is formed by patterning a 30-nm-thick non-doped amorphous silicon film formed on the gate insulating film 4 by the PE-CVD method. The source electrode 6s, the drain electrode 6d, and the drain bus line 5 are each formed of a 30 nm-thick n ⁺ -type amorphous silicon film, a 20-nm-thick titanium film, a 75-nm-thick aluminum film, and a 80-nm-thick titanium film. After the layers are sequentially formed on the insulating film 4 and the channel protection film 6b, these films are patterned by using one mask. The etching is performed by an RIE method using a mixed gas of BCl ₃ and Cl ₂ . At the time of the etching, the channel protective film 6b
Functions as an etching stop film.

The TFT 6 and the drain bus line 5 are covered with a protective insulating film 7 made of silicon oxide or silicon nitride. In a region on the protective insulating film 7 and surrounded by the two drain bus lines 5 and the two gate bus lines 2, a transparent pixel electrode 8 made of ITO having a thickness of 70 nm is formed. . Patterning of the ITO film is performed by a wet etching method using an oxalic acid-based etchant.

The pixel electrode 8 is connected to the source electrode 6s through the hole 7a of the protective insulating film 7. On the protective insulating film 7 and the pixel electrode 8, insulating protrusions 10 having a zigzag bending pattern extending in the Y direction are arranged at regular intervals in the X direction at positions indicated by two-dot chain lines in FIG. Is formed. The bending angle of the bending pattern is approximately 90
The bending point is located at substantially the center of the gate bus line 2. The side surface of the projection 10 is inclined with respect to the substrate surface.

As shown in FIGS. 15 to 18, the dielectric structure 11 interposed between the gate bus line 2, the drain bus line 5, and the pixel electrode 8 is formed on the protective insulating film 7. Are formed. Such a dielectric structure 11 and the projection 10 are formed, for example, by the following method.

That is, on the protective insulating film 7 and the pixel electrode 8,
A high-sensitivity negative resist and a low-sensitivity negative resist are sequentially applied. Then, a latent image having a bent pattern is formed on the high-sensitivity negative resist by the first exposure. In the first exposure, the exposure amount is set so as not to expose the low-sensitivity negative resist. Subsequently, the gate bus line 2, the drain bus line 5, and the peripheral area of the low-sensitivity negative resist are irradiated with exposure light to form a latent image. For example, in one pixel region, at least a region extending from above the gate bus line 2 to the edge of the pixel electrode 8 and a region reaching the edge of the drain bus line 5 and the pixel electrode 8 are irradiated with exposure light. By exposing the low-sensitivity negative resist, the high-sensitivity negative resist is simultaneously exposed in the same pattern. It should be noted that resists having different sensitivities can be said to be substantially the same dielectric material.

Thereafter, when the low-sensitivity negative resist and the high-sensitivity negative resist are simultaneously developed to form a pattern, the L-shaped dielectric structure 11 and the bent-pattern projection 10 as shown in FIG. It is formed as In this case, the projections 10 are composed of a high-sensitivity negative resist, and the dielectric structure is composed of both a low-sensitivity resist and a high-sensitivity negative resist. Thicker than

In the above-described example, the height of the dielectric structure 11 and the height of the projection 10 are different. However, if the height is the same, the photosensitive resist described above has only one layer. The above structure can be realized with the same man-hour.
For example, the film thickness of the dielectric structure 11 and the protrusion 10 is 1 μm.
m or more. Such protrusions 10 and dielectric structure 1
1 is covered with an alignment film 9 made of resin together with the pixel electrode 8 and the protective insulating film 7. The alignment film 9 has a vertical alignment.

Next, an opposing substrate opposing the first glass substrate 1 will be described. The opposing substrate is composed of a second glass substrate 12 as shown in FIG. 16, on which red (R),
Green (G) and blue (B) color filter films 13 are formed. On the color filter film 13, a black matrix 14 having a pattern facing the gate bus line 2, the drain bus line 5, and the capacitance bus line 3 is provided.
Are formed. Further, a transparent common electrode 15 made of ITO is formed on the color filter film 13 to cover the black matrix 14.

A projection 16 having a zigzag bending pattern is formed on the common electrode 15. The protrusions 16 are arranged at positions passing through substantially the centers of the plurality of protrusions 10 on the first glass substrate 1 as shown by a two-dot chain line in FIG. The projections 10 on the first glass substrate 1 side and the projections 16 on the second glass substrate 12 side
Intersect with the edge of the pixel electrode 8 at an angle of 45 degrees.

Further, the projection 1 is provided on the counter electrode 15.
6 is formed. The alignment film 17
Have a vertical orientation. The first glass substrate 1 and the second glass substrate 12 as described above are adhered at a predetermined distance from each other with the alignment films 9 and 17 inside, and a negative gap is provided between the alignment films 9 and 17. The liquid crystal material 18 having the dielectric anisotropy of? The liquid crystal molecules in the liquid crystal material 18 are oriented perpendicular to the substrate surface when no voltage is applied between the common electrode 15 and the pixel electrode 8. When an intermediate voltage is applied between the pixel electrode 8 and the common electrode 15, the liquid crystal molecules are inclined in a direction substantially perpendicular to the linear portions of the pattern of the protrusions 10 and 16.

The projections 10 and 16 correspond to the liquid crystal material 18.
It is desirable to be formed from a material having a dielectric constant equal to or less than the relative dielectric constant of. A first polarizing plate 21 is disposed on an outer surface of the first glass substrate 1, and
A second polarizing plate 22 is provided on the outer surface of the second glass substrate 12.
Are disposed, and the first polarizing plate 21 and the second polarizing plate 2
The arrangement of 2 is crossed Nicols, and the deflection axes of the first and second polarizing plates 21 and 22 intersect with the linear portions of the patterns of the projections 10 and 16 at an angle of 45 degrees when the substrate is viewed from the vertical. ing.

In the above-described embodiment, the structure is such that the dielectric structure 11 covers the area between the pixel electrode 8 and the gate bus line 2 and the drain bus line 5, respectively. As a result, the gap between the alignment film 9 on the gate bus line 2 and the alignment film 17 on the common electrode 15 is reduced, and the regulating force of the alignment film on the liquid crystal molecules is increased. In addition, a voltage drop occurs between the gate bus line 2 and the common electrode 15 due to the dielectric structure 11, and the voltage applied to the liquid crystal layer also decreases.

As a result, as shown in FIGS. 19A and 19B, the vertical alignment of the liquid crystal molecules L by the alignment films 9 and 17 is increased above the gate bus line 2, and the liquid crystal molecules L are hardly inclined. . This makes it difficult for the orientation direction of the liquid crystal molecules L to be fluctuated by the surrounding electric field, and reduces the fluctuation of the stray capacitance.
Further, the relative permittivity of the dielectric structure 11 is constant at about 2 to 5 and does not fluctuate, and is often smaller than the relative permittivity of the liquid crystal. For example, a dielectric constant of 3.2 is used. The liquid crystal for MVA has ε = 3.6 and ε // = 8.4.

As a result, as shown in FIGS. 19A and 19B, the capacitance Cgs between the pixel electrode 8 and the gate bus line 2 and the capacitance Cds between the pixel electrode 8 and the drain bus line 5 are almost changed. do not do. Further, since a voltage drop occurs in the dielectric structure 11, the voltage applied to the liquid crystal layer on the gate bus line 2 also decreases. As a result, the stray capacitance between the bus lines and between the bus line and the pixel electrode is reduced.

From the above, the fluctuation of the stray capacitance becomes very small, and a constant pixel potential is always obtained. Therefore, the width of the capacitance bus line 3 can be narrowed to increase the aperture ratio. Moreover, when the pixel potential becomes constant, the occurrence of flicker is prevented. For example, the common voltage fluctuation of the panel manufactured by adopting the above-mentioned structure is 10 mV or less, the flicker rate is improved to 3% or less, and the conventional flicker rate (5 to 7) is improved.
%). Thereby, the yield of the liquid crystal display panel can be improved.

In the above embodiment, the dielectric structure 11
And the projections 10 are formed in the same step, so that the above-described liquid crystal display device can be formed with almost no increase in the number of processes as compared with the related art. Note that the above-described dielectric structure 11 may protrude to such an extent that it slightly overlaps the pixel electrode 8. (Second Embodiment) In the first embodiment, in one pixel region, only a portion between the gate bus line 2, the drain bus line 5, and the pixel electrode 8 for driving the pixel electrode has a dielectric structure. It is structured to be covered with the object 11.

The arrangement region of the dielectric structure is not limited to this. For example, as shown in FIG. 20, a dielectric structure 11a may be provided between adjacent pixel electrodes 8. The structure is such that the periphery of the pixel electrode 8 and the gate bus line 2 and the drain bus line 5 are covered with the dielectric structure 11a. By adopting such a structure, the flicker rate is further improved than that of the first embodiment.

Further, only the portion between the gate bus line 2 and the pixel electrode 8 may be covered with the dielectric structure, or only the portion between the drain bus line 5 and the pixel electrode 8 may be covered with the dielectric structure. According to these, the effects were not as good as those of the dielectric structures 11 and 11a shown in FIG. 15 or FIG. 20, but both the common voltage fluctuation and the flicker rate were good. Further, in FIG. 14, the gate bus line 2 and the protrusion 1
The dielectric structure may be formed only in the region where 1 intersects and the region in the vicinity thereof, or the dielectric structure may be formed only in the region where the drain bus line 5 intersects with the protrusion 11 and the region in the vicinity thereof. You may. According to these, it is confirmed that the influence of the electrification of the protrusion 10 is reduced as compared with the first embodiment, and that the change in the orientation between the gate bus line 2 and the pixel electrode 8 near the protrusion 10 can be suppressed. Was done. In this case, the flicker rate was not as effective as the dielectric structure shown in FIG. 15 or FIG. 20, but both the common voltage fluctuation and the flicker rate were good.

In the above description, the dielectric structure is formed on the first glass substrate 1 side, but it may be formed on the second glass substrate (counter substrate) 12 side. For example, as shown in FIG. 21, the common electrode 15 at a position where the dielectric structures 11 and 11a shown in FIG. 15 or FIG.
A dielectric structure 11b is formed thereon, and an alignment film 17 is formed thereon.
May be adopted. In this case, there is no effect of completely fixing the stray capacitance Cgs between the gate and the pixel electrode and the stray capacitance Cds between the drain and the pixel electrode. However, an effect of minimizing the change in orientation due to the effect of narrowing the cell gap can be expected. . The effect of such a narrow cell gap becomes remarkable as in the first embodiment when the thickness of the dielectric structure 11b is 1 μm or more.

Further, in the above-described example, the dielectric structure is formed of, for example, only a resist. However, as shown in FIG. 22, the red, green, and blue color filters 13R, 13R may be used.
By superimposing G and 13B at the boundary between pixels, the superposed portion may be applied as a part of the dielectric structure on the counter substrate side. Thereby, the liquid crystal can be removed from a portion other than the pixel electrode 8 where the alignment change is suppressed, and a capacitance change due to the alignment change does not occur, so that the same effect as in the first embodiment can be obtained.

The different color filters 13R, 1R
The portion where 3G and 13B are overlapped may be only between the gate bus line 2 and the pixel electrode 8, or only between the drain bus line 5 and the pixel electrode 8. In this case, a dielectric structure may be formed on the first glass substrate 1 so as to face the portion where the color filters 13R, 13G, and 13B of different colors overlap.

The red, green and blue color filters 13R, 1
As shown in FIG. 22, the dielectric structure 11c may be formed on the 3G and 13B overlapping portions, or may be omitted. However, if the configuration as shown in FIG. 22 is adopted, the color filters 13R, 13G, 13B
If the overlapped portion and the dielectric structure 11c thereon are used as columns for maintaining the cell gap, the spacer interposed between the substrates becomes unnecessary.

The above-described dielectric structure may be formed on both the second glass substrate 12 side and the first glass substrate 1 side. The cell gap may be maintained. Then, by adopting an optimal structure, the common voltage fluctuation can be reduced to 10 mV or less and the flicker rate can be reduced to 2% or less.

The above-mentioned projection 1 on the first glass substrate 1 side
0, a structure in which at least one of the projections 16 on the first glass substrate 1 side is not provided around a region intersecting the gate bus line 2 or a structure not provided around a region intersecting the drain bus line 5 Alternatively, a structure that is not provided other than on the pixel electrode 8 may be adopted. In the first and second embodiments described above, the projection is used as a means for regulating the alignment direction of the liquid crystal, but a slit may be formed in at least one of the pixel electrode and the common electrode instead of the projection.

The dielectric structure shown in the first embodiment and the second embodiment is not limited to the MVA type liquid crystal display device, but may be applied to other liquid crystal display devices. In that case, a slit formed in the pixel electrode 8 or the common electrode 15 may be used instead of the protrusions 10 and 16 on either the first glass substrate 1 side or the second glass substrate 12 side.

The first and second embodiments are based on the following invention. (1) A liquid crystal having a negative dielectric anisotropy is sandwiched between the first and second substrates on which vertical alignment treatment is performed on the substrate surface, and the alignment of the liquid crystal is almost vertical when no voltage is applied. A liquid crystal display device which is substantially horizontal when a predetermined voltage is applied and which is inclined when a voltage smaller than the predetermined voltage is applied, the voltage being provided on the first substrate and being smaller than the predetermined voltage. A first domain regulating means for regulating an orientation direction in which the liquid crystal becomes oblique when a voltage is applied, and an orientation in which the liquid crystal is oblique when a voltage smaller than the predetermined voltage is applied, provided on the second substrate. The second domain regulating means for regulating a direction and the first domain regulating means are provided at least on an electrode of the first substrate, and are part of a contact surface of the first substrate with the liquid crystal. The slope of the liquid crystal And the projection of the dielectric projecting towards,
A plurality of first bus lines formed at intervals on a surface of the first substrate or the second substrate that sandwiches the liquid crystal, intersecting the first bus line; A plurality of second bus lines formed at intervals above the first bus line; and pixels formed in a region defined by the first bus line and the second bus line. An electrode, a portion corresponding to at least a part of a region between the pixel electrode and the first bus line,
A liquid crystal display device having a dielectric structure different from the protrusion formed on at least one of the first substrate and the second substrate.

(2) The projection and the dielectric structure are formed from the same material in the same step.
The liquid crystal display device according to (1). (3) The dielectric structure includes the first bus line and the second bus line.
The liquid crystal display device according to (1), wherein the liquid crystal display device is also formed on at least one of the bus lines. (4) The second domain regulating means is a protrusion protruding into the liquid crystal layer, or a slit obtained by partially extracting an electrode on the second substrate side. The liquid crystal display device as described in the above.

(5) A red, green, or blue color filter is formed facing the pixel electrode, and the dielectric structure is constituted by the color filters overlapped in a region not facing the pixel electrode. The liquid crystal display device according to (1), which is characterized in that: (6) The region not facing the pixel electrode is at least one of between the first bus line and the pixel electrode or between the second bus line and the pixel electrode. 3. The liquid crystal display device according to 1.).

(7) The liquid crystal display device according to (5), wherein another dielectric structure is further superimposed on the area where the color filters are superimposed. (8) Another dielectric structure is formed facing the region where the color filters are overlapped, (5)
3. The liquid crystal display device according to 1. (9) The liquid crystal display device according to (1), wherein the dielectric structure is formed up to a region protruding from a part of the pixel electrode. (10) At least one of the first domain regulating unit and the second domain regulating unit is not provided outside the pixel electrode, or at least one of the first bus line and the second bus line. The liquid crystal display device according to (1), wherein the liquid crystal display device is not provided around an area intersecting with. (11) The liquid crystal display device according to (1), wherein the thickness of the dielectric structure is 1 μm or more. (Third Embodiment) FIG. 23 is a sectional view showing a third embodiment of the present invention. The structure is the same as that of the first embodiment except for a pixel electrode, a protrusion, and a dielectric structure. I have. FIG.
3, the same reference numerals as in FIG. 10 indicate the same elements.

In FIG. 23, a first glass substrate (TF
A gate bus line 2 and a capacitance bus line 3 are formed on a (T substrate) 1. In addition, those bus lines 2,
A drain bus line 5 and a thin film transistor (TFT) 6 are formed on the gate insulating film 4 covering the gate insulating film 3 as in the first embodiment.
Are formed. The drain bus line 5 and the thin film transistor (TFT) 6 are covered with a protective insulating film 7, and a pixel electrode 30 is formed on the protective insulating film 7. The pixel electrode 30 is, as shown in FIG.
And a drain bus line 5.

The pixel electrode 30 has a capacitance bus line 3
The slits 30a and 30b are extended from the edge area of the pixel electrode 30 existing above in a V-shape, and slits 30c and 30d are formed in the pixel electrode 30 in parallel with the slits 30a and 30b. I have. The slit width is, for example, 10 μm. These slits (domain regulating means) 30a to 30d are
Is divided into five regions. Those areas are slit 3
0a to 30d are electrically connected to each other through a connecting portion 30n that divides the connecting portions 30a to 30d into a plurality.

Further, the slit 3 is set within a predetermined width w ₁ from the edge of the pixel electrode 30 to the inside, for example, 4 μm.
A connection portion 30e for electrically connecting the five regions divided by Oa to 30d is secured, and the connection portion 3e is provided.
The ends of the slits 30a to 30d are divided by 0e. The connection portion 30e serves as an alignment control unit that forms an alignment singular point of s = -1. According to the orientation control means having an orientation singular point of s = -1, FIG.
As shown in (2), in two directions orthogonal to each other with the point O as the center, the liquid crystal molecules L in one direction are oriented to the point O, and the liquid layer molecules L in the other direction are oriented to be opposite to the point O. In addition, the liquid crystal molecules L that are inclined 45 degrees with respect to those directions face different directions.

Note that s as described in the following embodiment will be described.
According to the orientation control means for forming the orientation singular point of = + 1,
As shown in FIG. 25B, all the liquid crystal molecules L around the point O are oriented toward the point O. Pixel electrode 30 as described above
Are connected to the TFT 26 as shown in FIG. 23 and are further covered with the alignment film 9.

On the surface of the second glass substrate (opposite substrate) arranged to face such a pixel electrode 30, FIG.
As shown in FIG. 3, similarly to the first embodiment, a color filter 13, a black matrix 14, a common electrode 15, a dielectric protrusion (domain regulating means) 31, and an alignment film 17 are formed in this order. The first and second glass substrates 1 and 2
For example, JALS-684 (trade name, manufactured by JSR Corporation) is used as the alignment films 9 and 17 on the top 12.

As shown by the two-dot line in FIG. 24, the dielectric projection 31 is formed on the pixel electrode 3 in the same manner as in the first embodiment.
It is formed in a zigzag manner facing a position passing between the 0 slits 30a to 30d. The projection 31 is made of, for example, photosensitive acrylic resin PC-335 (trade name manufactured by JSR).
Is formed from. The formation of the pattern of the protrusion 31
After spin coating the resin on the substrate,
For 2 minutes, selectively irradiate ultraviolet rays using a photomask, and apply an organic alkali-based developer (TMAHO, 2 wt.
%) And baked at 200 ° C. for 60 minutes. The width of the projection 31 was 10 μm and the height was 1.5 μm.

The first glass substrate 1 and the second glass substrate 12 having the above-described configuration were bonded to each other, and liquid crystal was injected between them to form a liquid crystal panel. The liquid crystal material used was Merck's trade name MJ96213.
In the liquid crystal display device having the above-described configuration, the slits 30a to 30d of the pixel electrode 30 as the domain control unit are provided.
Was not present at the edge of the pixel electrode 30 and its periphery, but a singular point for alignment control was formed there. This allows
The difference between the domain states of white when the pixel display responds from black to white and white when the pixel display responds from halftone to white can be reduced to an inconspicuous level,
The domain change was reduced to a level that could not be recognized as an afterimage.

The means for controlling the domain of liquid crystal molecules is not limited to a linear slit in a pixel electrode. For example, instead of the slit, a structure in which a linear dielectric protrusion is provided on the pixel electrode as in the first embodiment may be adopted. In this case, if a divided portion that does not intersect with the edge of the pixel electrode is formed on the projection, an alignment singular point of s = −1 is formed at the edge of the pixel electrode on an extension of the projection.

Instead of forming the projection 31 on the common electrode 15 formed on the counter substrate 12 side, a slit may be formed in the common electrode 15. (Fourth Embodiment) In the third embodiment, an alignment singular point of s = -1 is formed at a portion where a structure or a slit formed on a pixel electrode intersects an edge of the pixel electrode. In the present embodiment, a structure in which an alignment singular point of s = + 1 is formed at a portion where a structure formed on a substrate facing a substrate having a pixel electrode or a slit intersects an edge of the pixel electrode will be described.

FIG. 26 is a plan view showing a pixel electrode of a liquid crystal display device according to a fourth embodiment of the present invention, and FIG.
It is the VII-VII sectional view. In FIG. 26, slits 33a and 33b are extended from the edge region of the pixel electrode 33 existing on the capacitance bus line 3 so as to extend in a V-shape, and the region of the pixel electrode 30 near the gate bus line 2 is provided with these slits. Another slit 33c, 33d parallel to the slits 33a, 33b is further formed. The slit width is, for example, 10 μm. The slit 33a ~
33 d is also formed on the edge of the pixel electrode 33.
The slits 33a to 33d are separated by a connecting portion 33e.

As shown in FIGS. 26 and 27, in the dielectric protrusion (structure) 34 formed on the counter substrate 12 side, the portion 34a facing the edge of the pixel electrode 33 is set to be different from other regions. In addition, the alignment singular point near the edge of the pixel electrode 33 was formed at s = + 1 by increasing the height. The height of the portion of the protrusion 34 facing the edge of the pixel electrode 33 is set to 2.
5 μm, and the height of other portions was 1.5 μm.

The protrusions 34 are formed using the same constituent material as the protrusions 31 of the third embodiment. First, a pattern of the protrusions 34 is formed on the common electrode 15 at a height of 1.5 μm. Further, a protrusion 34 a having a height of 1.0 μm is selectively stacked on a region facing the edge of the pixel electrode 33. As described above, the portion of the protrusion 34 on the counter substrate 12 side that faces the edge of the pixel electrode 33 is made higher than the other portions, so that the edge of the pixel electrode 33 has an s as shown in FIGS. = + 1 orientation singularities will be formed.
As a result, the influence of the alignment of the liquid crystal molecules L at the edge of the pixel electrode 33 on the liquid crystal molecules inside the pixel electrode 33 is prevented by the alignment singularity, and the halftone display is changed to the white display. The occurrence of an afterimage at the time of occurrence is prevented.

When a slit is formed in the common electrode 15 of the counter substrate 12 in place of the projection 34, the same effect can be obtained even if the slit is divided at a portion facing the pixel electrode 33. Incidentally, the combination of the TFT substrate of the third embodiment and the counter substrate of the fourth embodiment has the best structure. That is, the linear slits or protrusions formed on the TFT substrate side are divided so as not to intersect the edges of the pixel electrode, and the linear slits in the common electrode on the counter electrode side are not intersected with the pixel electrode. It is preferable that the portion of the linear protrusion on the counter electrode side facing the edge of the pixel electrode be made thicker than the others. (Fifth Embodiment) In the third embodiment, the bent portion of the slit formed on the pixel electrode, that is, the intersection of the extension of the slit in two directions is aligned with the edge of the pixel electrode.
The intersection may be shifted inward from the edge of the pixel electrode.

FIG. 28 is a plan view showing a pixel electrode and its periphery of a liquid crystal display device according to a fifth embodiment of the present invention. FIG.
In FIG. 8, the bent portion 35b of the slit 35a formed in the pixel electrode 35 is formed so as to recede from the edge of the pixel electrode 35 to the inside. The distance from the bent portion 35b to the edge of the pixel electrode 35 is, for example, 4 μm.
The width of the slit 35a was 10 μm.

Further, on the counter substrate 12 side, a projection 36 is formed at a position passing between the slits 35 as in the first embodiment. According to this, the influence of the electric field due to the edge of the pixel electrode 35 on the bent portion 35b of the slit 35a can be reduced, and the occurrence of an afterimage is suppressed. In FIG. 28, the pixel electrode 35 has a structure in which a slit is provided. However, when a dielectric protrusion is formed on the pixel electrode 35 instead of the slit as in the first embodiment, the protrusion is bent. By retreating the portion inward from the edge of the pixel electrode, the effect of the electric field due to the edge of the pixel electrode 35 on the bent portion of the protrusion can be reduced, and there is an effect of suppressing the occurrence of an afterimage.

As shown in FIG. 29, for example, as shown in FIG. 29, the shape of the dielectric protrusion 37 formed on the counter substrate 12 as an alignment control means is bent in a region facing the pixel electrode, and the bent portion is formed in the pixel. Even if it is displaced inward from the edge of the electrode 38, the influence of the electric field due to the edge of the pixel electrode 38 on the bent portion can be reduced, and an afterimage suppressing effect is achieved. In this case, the width of the projection 37 is, for example, 10 μm, and the distance between the bent portion and the edge of the pixel electrode 38 is, for example, 4 μm.

It is conceivable to form a slit in the common electrode 15 shown in FIG. 23 instead of the dielectric projection 37 as the alignment control means on the counter substrate 12. However, since the color filter 13 is usually formed below the common electrode 15, it is not preferable to form a slit in the common electrode 15 in terms of accuracy and reliability. In FIG. 29, since the bent portions (intersections) of the slits 38a and 38b formed in the pixel electrode 38 and extending in two directions exist outside the pixel electrode 38, the pixel electrode 3
The influence of the electric field due to the edge of No. 8 on the bent portion is eliminated, and the occurrence of an alignment state different from the original alignment control by the protrusions or slits can be reduced, and the display is changed from halftone display to white display. In this case, afterimages can be eliminated. (Sixth Embodiment) FIG. 30A is a plan view showing a pixel electrode and its periphery of a liquid crystal display device according to a sixth embodiment of the present invention.

In FIG. 30A, the first and second slits 4 formed in a V shape near the center of the pixel electrode 40 are shown.
A structure is adopted in which the intersection of 0a and 40b is connected inside the edge by a slit 40e parallel to the edge of the pixel electrode 40. The distance of the gap 40g between the slit 40e and the edge of the pixel electrode 40 is, for example, 4 μm.
It is.

The pixel electrode 40 also has third and fourth slits 40c, 40c near the gate bus line 2.
d is formed. Those first to fourth slits 4
0a to 40d are divided at a plurality of locations by a connecting portion 40f. Accordingly, the pixel electrode 40 is divided into five regions A to E by the first to fourth slits 40a to 40d, and the regions A to E are electrically connected by the connecting portion 40f. The region C divided by the second slits 40a and 40b is electrically and structurally opposed to the storage capacitor forming electrode (capacitor bus line) 3. In addition, at least two electrical connection paths are connected to the storage capacitor forming electrode 3.
And are electrically opposed.

As a result, the connection between the region B and the region D of the pixel electrode 40 is established as shown in FIG.
And the route BD. When the region C of the pixel electrode 40 and the storage capacitor forming electrode 3 are short-circuited, the electrical connection between B-C and between C-D
Since the four regions A, B, D, and E of the pixel electrode 40 are electrically connected to each other through the continuous connecting portion 40f and the gap 40g by being separated by irradiating the laser beam to 0f, a large region other than the region C is provided. Driving of liquid crystal molecules in a partial region becomes possible.

The pixels that can be driven except for the region C are the storage capacitor forming electrode 3 and the region C of the pixel electrode 40.
The display characteristics are slightly different from those in the normal state where the TFT is not short-circuited. However, depending on the number and location of the pixels in such a state, the level of the display defect can be cleared. Improvement is achieved. this is,
Multiple areas of the pixel electrode divided by the slit are
This is achieved by a structure connected by the edge portions of the pixel electrodes, which is different from the conventional structure.

If the pixel electrode 40 is divided into at least three regions by, for example, the first and second slits 40a and 40b, such an effect of improving the yield can be obtained. Next, a change in a domain on a slit when the present invention is applied will be described with reference to FIG.

First, as shown in FIG. 31A, when the display is changed from black display to white display, the number of domains on the slit 40a divided by the connecting portion is eight. According to FIG. 31 (a), FIG.
Compared to (a), the number of domains increases. This is because a singular point of the orientation vector of s = -1 is formed at the edge of the pixel electrode.

When the display changes from black display to white display through halftone display, the domain connected to the domain disappears as shown in FIG. 31 (b). That is, FIG.
Compared with (a), the domain change on the slit is suppressed to a very small level near the edge of the pixel electrode. The above-described third to sixth embodiments are based on the following invention. (1) In a vertical alignment type liquid crystal display device in which at least one of a pair of substrates having electrodes is provided with a linear structure or a linear slit made up of a plurality of constituent units to control liquid crystal alignment when voltage is applied. An alignment control means for causing liquid crystal molecules to form an alignment singularity of s = -1 at a portion where a structure on the electrode or a slit in the electrode intersects an edge of a pixel electrode on one of the substrates. A liquid crystal display device comprising:

(2) The electrode is a pixel electrode or a common electrode. (3) The linear structure is formed on the pixel electrode or the common electrode. Liquid crystal display device. (4) The liquid crystal display device according to (1), wherein the slit is not formed at the edge of the pixel electrode on the extension of the slit.

(5) The structure is divided above or above the edge of the pixel electrode.
The liquid crystal display device according to (1). (6) In a vertical alignment type liquid crystal display device in which at least one of a pair of substrates having electrodes is provided with a linear structure or a linear slit composed of a plurality of constituent units to control liquid crystal alignment when voltage is applied. In a portion where the structure or the slit formed on one side of the substrate and the edge of the pixel electrode formed on the other side of the substrate intersect, liquid crystal molecules s.
A liquid crystal display device comprising an alignment control means for forming an alignment singular point of = + 1.

(7) At least one of a pair of substrates having electrodes is provided with a linear structure or a linear slit comprising a plurality of structural units having a bent portion to control the liquid crystal alignment when a voltage is applied. In a vertical alignment type liquid crystal display device, the structure or the bent portion of the slit on one of the substrates having a pixel electrode is off the edge of the pixel electrode. .

(8) At least one of a pair of substrates having electrodes is provided with a linear structure or a linear slit comprising a plurality of structural units having a bent portion to control the liquid crystal alignment when a voltage is applied. In a vertical alignment type liquid crystal display device, the bent portion of the structure or the slit disposed on the other substrate, facing the pixel electrode on one of the substrates, is positioned above an edge of the pixel electrode. Is not disposed.

(9) An electrode for forming a storage capacitor formed on the first substrate, an active element formed on the first substrate, and an active element connected to the active element on the first substrate. A pixel electrode formed and divided into at least three regions by a slit, wherein an electrical connection from one region of the three regions to another region of the pixel electrode passes through the region. A thin film transistor substrate having a plurality of different paths. (10) The thin film transistor substrate according to (9), wherein at least two of the paths of the electrical connection are electrically opposed to the storage capacitor forming electrode. (11) The thin film transistor substrate according to (10), wherein an area facing the storage capacitor electrode is different for each of the paths facing the storage capacitor forming electrode. (12) The thin film transistor substrate according to (12), wherein the thickness of the dielectric layer in the region facing the storage capacitor forming electrode is different for each path facing the storage capacitor forming electrode. (13) The thin film transistor substrate according to any one of (10) to (12), wherein the magnitude of the storage capacitance is different for each path facing the storage capacitance forming electrode. (14) A liquid crystal display device having the thin film transistor substrate according to any one of (9) to (13). (15) The liquid crystal display device according to any one of (1) to (8), including the thin film transistor substrate according to any one of (9) to (13).

[0119]

As described above, according to the present invention, a region between a gate bus line (first bus line) and a pixel electrode which intersect each other, or a drain bus line (second bus line) and a pixel Since the dielectric structure is arranged in the region between the electrodes, the dielectric constant between the pixel electrode and the bus line is fixed by the dielectric structure, and the variation in stray capacitance between them can be suppressed. In addition, since the dielectric structure is also formed on the bus line, the liquid crystal layer on the dielectric structure is thinned, and the liquid crystal molecules in the liquid crystal layer are hardly moved from the vertical alignment, and floating. Capacitance fluctuation can be made very small. In addition, since the component fixed by the dielectric structure in the stray capacitance above the bus line increases, the fluctuation of the stray capacitance can be reduced.

As described above, when the fluctuation of the stray capacitance is suppressed, the pixel potential becomes constant and the occurrence of flicker can be prevented. In addition, it is possible to increase the aperture ratio by reducing the width of the capacitance bus line for suppressing the fluctuation of the capacitance. According to the present invention, in a display system in which liquid crystal alignment is controlled by a structure or a slit provided on a substrate, a liquid layer molecule is formed at a portion intersecting a pixel electrode on an extension of the structure or the slit. Response characteristics are improved by forming an orientation singular point such that s = + 1 or s = + 1.

Further, according to the present invention, as the electrical connection path of the pixel electrode, two paths are provided: a path through an area for forming the storage capacitor forming electrode and the capacitor, and a path without the storage electrode. When an electrical short circuit occurs between the formation electrode and the pixel electrode, the area where the capacitor is formed is electrically cut off from the other area, and the other area is used as an area where liquid crystal molecules can be driven. And T
The production yield of the FT substrate can be improved.

[Brief description of the drawings]

FIG. 1 is a diagram showing a change in an image according to a viewing angle of a conventional TN type LCD.

FIG. 2 is a diagram showing a driving state of a conventional VA liquid crystal display.

FIG. 3 is a diagram illustrating the effect of orientation division in a conventional VA system.

FIG. 4 is a diagram showing various types of conventional orientation division.

FIG. 5 is a plan view of a conventional MVA pixel unit.

FIG. 6 is a diagram showing a conventional MVA type pixel section,
It is an I line sectional view.

FIG. 7 is a plan view of a conventional MVA pixel unit.

FIG. 8 is a diagram showing an off state and an on state of a conventional MVA liquid crystal panel.

FIG. 9 is a diagram showing a change in the orientation direction of liquid crystal molecules in a conventional MVA liquid crystal panel.

FIG. 10 is a diagram showing the orientation direction of liquid crystal molecules in the conventional MVA mode halftone display.

FIG. 11 is a diagram showing combinations of orientation directions of liquid crystal molecules on a slit on a pixel electrode of a conventional MVA method.

FIG. 12 is a diagram showing an orientation direction of liquid crystal molecules near an edge of a pixel electrode after a conventional VA liquid crystal display changes from halftone display to white display.

FIG. 13 is a plan view showing a cut state of a pixel electrode in a conventional VA system and an equivalent circuit diagram thereof.

FIG. 14 is a plan view of a pixel region showing an arrangement of a domain regulating unit according to the first embodiment of the present invention.

FIG. 15 is a plan view of a pixel region in which a dielectric structure and a protrusion are formed according to the first embodiment of the present invention.

FIG. 16 is a sectional view taken along line II-II of FIG. 15 in a pixel region according to the first embodiment of the present invention.

FIG. 17 is a sectional view taken along line III-III of FIG. 15 in a pixel region according to the first embodiment of the present invention.

FIG. 18 is a sectional view taken along line VI-VI of FIG. 15 in a pixel region according to the first embodiment of the present invention.

FIG. 19 is a cross-sectional view illustrating an operation in the pixel region according to the first embodiment of the present invention.

FIG. 20 is a plan view illustrating a pixel region of a liquid crystal display device according to a second embodiment of the present invention.

FIG. 21 is a sectional view taken along line VV of FIG. 20 showing a pixel region of the liquid crystal display device according to the second embodiment of the present invention.

FIG. 22 is a sectional view taken along the line VI-VI of FIG. 20, showing a TFT according to a second embodiment of the present invention and its periphery.

FIG. 23 is a sectional view illustrating a pixel region of a liquid crystal display device according to a third embodiment of the present invention.

FIG. 24 is a plan view illustrating a pixel region of a liquid crystal display device according to a third embodiment of the present invention.

FIG. 25 is a diagram illustrating the alignment direction of liquid crystal molecules at an alignment singular point according to the embodiment of the present invention.

FIG. 26 is a plan view illustrating a pixel region of a liquid crystal display device according to a fourth embodiment of the present invention.

FIG. 27 is a sectional view taken along line VII-VII of FIG. 26 in a pixel region of a liquid crystal display device according to a fourth embodiment of the present invention.

FIG. 28 is a plan view of a pixel region of a liquid crystal display device according to a fifth embodiment of the present invention.

FIG. 29 is a plan view illustrating an example of another pixel region of the liquid crystal display device according to the fifth embodiment of the present invention.

FIG. 30 is a plan view in a pixel region of a liquid crystal display device according to a sixth embodiment of the present invention.

FIG. 31 is a diagram showing an example of the effect of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... 1st glass substrate (TFT substrate), 2 ... Gate bus line, 3 ... Storage capacity formation electrode (capacitance bus line), 4
... Gate insulating film, 5 ... Drain bus line, 6 ... TF
T, 7: protective insulating film, 8: pixel electrode, 9: alignment film, 10
... Protrusion, 11, 11a, 11b, 11c ... Dielectric structure, 12 ... Second glass substrate (counter substrate), 13, 13
R, 13G, 13B: color filter, 14: black matrix, 15: counter electrode, 16: protrusion, 17: alignment film, 18: liquid crystal, 30, 33, 35, 38: pixel electrode, 31, 34, 36, 37 ... Structure.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Koji Tsukadai, Inventor Koji Tsukadai 650 Otsuka, Yonago, Yonago, Tottori Pref. Yonago Fujitsu Limited (72) Inventor Yoshiro Koike 4-1-1 Kamiodanaka, Nakahara-ku, Kawasaki, Kanagawa Prefecture No. 1 F-term in Fujitsu Limited (Reference) 2H090 HA03 HA05 HA07 HA08 HB13X JA03 JC03 KA18 LA02 LA04 LA15 MA01 MA07 MA15 2H092 JA26 JA36 JA40 JA44 JB04 JB05 JB57 JB64 JB66 KA05 KA07 KB14 KB24 MA08 NA07 NA21 A02A03 PA03 PA03 BA03 BA43 CA19 EA04 ED20 FA04

Claims (8)

[Claims] 1. A vertical alignment type liquid crystal display in which a linear structure or a linear slit comprising a plurality of constituent units is provided on at least one of a pair of substrates having electrodes to control liquid crystal alignment when voltage is applied. In the device, the liquid crystal molecules are aligned at a portion where a structure on the electrode or a slit in the electrode and an edge of the pixel electrode on one of the substrates intersect to form an alignment singularity of s = -1. A liquid crystal display device comprising a control unit. 2. A vertical alignment type liquid crystal display in which a linear structure or a linear slit comprising a plurality of constituent units is provided on at least one of a pair of substrates having electrodes to control liquid crystal alignment when voltage is applied. In the device, liquid crystal molecules form an alignment singular point of s = + 1 at a portion where the structure or the slit formed on one of the substrates and the edge of a pixel electrode formed on the other of the substrates intersect. A liquid crystal display device, comprising: an alignment control unit for performing the operation. 3. A vertical structure for controlling liquid crystal alignment when a voltage is applied by providing a linear structure or a linear slit comprising a plurality of structural units having a bent portion on at least one of a pair of substrates having electrodes. An alignment-type liquid crystal display device, wherein the bent portion of the structure or the slit on one of the substrates having a pixel electrode is off the edge of the pixel electrode. 4. A vertical structure for controlling liquid crystal alignment when a voltage is applied by providing a linear structure or a linear slit comprising a plurality of constituent units having a bent portion on at least one of a pair of substrates having electrodes. In the alignment type liquid crystal display device, the bent portion of the structure or the slit disposed on the other substrate facing the pixel electrode on one of the substrates is provided on an edge of the pixel electrode. A liquid crystal display device which is not arranged. 5. An electrode for forming a storage capacitor formed on a first substrate, an active element formed on the first substrate, and formed on the first substrate connected to the active element. And a pixel electrode divided into at least three regions by slits, and an electrical connection from one region of the three regions to another region of the pixel electrode is different from the region through which the pixel electrode passes. A thin film transistor substrate having a plurality of paths. 6. A liquid crystal display device having the thin film transistor substrate according to claim 5. 7. A liquid crystal display device according to claim 1, comprising the thin film transistor substrate according to claim 5. 8. A liquid crystal having a negative dielectric anisotropy is sandwiched between a first substrate and a second substrate having a vertical alignment treatment applied to the surface of the substrate, and the alignment of the liquid crystal is changed when no voltage is applied. Almost vertically,
In a liquid crystal display device which is oriented substantially horizontally when a predetermined voltage is applied and becomes oblique when a voltage smaller than the predetermined voltage is applied, a voltage which is provided on the first substrate and which is smaller than the predetermined voltage is applied. A first domain regulating means for regulating an orientation direction in which the liquid crystal becomes oblique when the liquid crystal is tilted, and an orientation direction in which the liquid crystal is oblique when a voltage smaller than the predetermined voltage is applied to the second substrate. A second domain regulating unit for regulating, and the first domain regulating unit includes at least the first domain regulating unit.
A dielectric projection provided on an electrode of the first substrate and projecting toward the liquid crystal layer that makes a part of a contact surface of the first substrate with the liquid crystal be inclined, and wherein the first substrate or the first A plurality of first bus lines formed at intervals on a surface of the second substrate that sandwiches the liquid crystal, and a plurality of first bus lines intersecting with the first bus lines, and A plurality of second bus lines formed at intervals above, a pixel electrode formed in a region defined by the first bus line and the second bus line, A portion corresponding to at least a part of a region between the first bus lines, and having a dielectric structure different from the protrusion formed on at least one of the first substrate and the second substrate; A liquid crystal display device characterized by the above-mentioned.