JPH11109393A - Liquid crystal display device, its production and its driving method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To speed up response with a high contrast and to improve a visual angle characteristic without making stages laborious by providing the positions of the apertures disposed in the electrodes on at least one of substrates with second electrodes for controlling the initial alignment of liquid crystals. SOLUTION: A layer consisting of liquid crystal molecules 11 negative in dielectric constant anisotropy is held between two sheets of substrates 23, 33 respectively having the electrodes 22, 32. Perpendicular alignment layers 21, 31 are applied on the respective electrodes 22, 23 and are subjected to rubbing at need. The electrodes 22 of the one substrate 23 are provided with the apertures 24 and are further provided with the electrodes 25 for controlling the initial alignment of the liquid crystals in the same positions as the positions of the apertures. Different voltages are applied on the electrodes 22 and the second electrodes 25. In such a case, the voltage larger than the voltages impressed on, for example, the electrodes 22 and the electrodes 32 is impressed between the second electrodes 25 and the electrodes 32, by which diagonal electric fields are generated within the liquid crystal layer. Then, the liquid crystal molecules 11 fall in the direction along the diagonal electric fields.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device, a method of manufacturing the same, and a method of driving the same, and more particularly to a liquid crystal display device which is easy to manufacture and has excellent viewing angle characteristics, a method of manufacturing the same, and a method of driving the same.

[0002]

2. Description of the Related Art Twisted nematic (TN), which has been widely used in the past, is hereinafter referred to as "TN".
Abbreviated. In the liquid crystal display device of the type), the liquid crystal molecules change the direction of the alignment vector in the direction of the electric field according to the applied voltage from the "white" display state in which the liquid crystal molecules are parallel to the substrate surface when no voltage is applied. By going, "white"
The display state gradually changes to a “black” display state. However, there is a problem that the viewing angle of the TN type liquid crystal display device is narrow due to the specific behavior of the liquid crystal molecules due to the application of the voltage. The problem that the viewing angle is narrow is particularly remarkable in the rising direction of liquid crystal molecules in halftone display.

As a method for improving the viewing angle characteristics of a liquid crystal display device, Japanese Patent Application Laid-Open No. 4-261522 or Japanese Patent Application Laid-Open
A technique as disclosed in Japanese Patent No. 43461 is proposed. In these techniques, a homeotropically aligned liquid crystal cell is manufactured, sandwiched between two polarizing plates installed so that their polarization axes are orthogonal to each other, and a common electrode 32 having an opening 34 is used as shown in FIG. By doing so, a non-uniform electric field is generated in each pixel, whereby each pixel is divided into two or more liquid crystal domains, and the viewing angle characteristics are improved. In Japanese Patent Application Laid-Open No. Hei 4-261522, by controlling the direction in which the liquid crystal tilts particularly when a voltage is applied,
High contrast is realized. Also, Japanese Patent Application Laid-Open No. 6-43
As described in Japanese Patent No. 461, an optical compensator is used as necessary to improve the black viewing angle characteristics. Further, in Japanese Patent Application Laid-Open No. 6-43461, not only a liquid crystal cell with homeotropic alignment but also a cell with TN alignment, each pixel is divided into two or more domains by a non-uniform electric field, and the viewing angle characteristics are improved. Has improved.

[0004]

However, these techniques require a "fine processing step such as a photoresist step for the common electrode 32" which is not required in a normal TN type liquid crystal display device manufacturing process. Along with
There is a problem that an advanced bonding technique of the upper and lower substrates 23 and 33 is required. This problem is particularly serious in an active matrix liquid crystal display device using a switching element such as a TFT. That is, in an ordinary active matrix liquid crystal display device, an active element such as a thin film diode is manufactured on one transparent substrate, so that a fine processing step such as a photoresist step is required on one side for manufacturing the active element. The other substrate, which is usually called a "common electrode", does not need to be subjected to fine processing, and only has an electrode formed on the entire surface. However, in the above-described conventional technology, a fine processing step such as a photoresist step is required for a “common electrode” that does not normally require fine processing. Advanced bonding techniques will be required.

In the prior art, as shown in FIG. 6, since there is no electrode in the portion of the opening 34, even when a voltage is applied to the electrode 32, a sufficient electric field is not applied to this portion. However, there is a disadvantage that the liquid crystal does not sufficiently respond to the applied voltage.

Accordingly, an object of the present invention is to provide a liquid crystal display having a high contrast, a fast response, and excellent viewing angle characteristics without increasing the above-mentioned problems of the prior art, that is, an increase in complicated steps such as a photoresist step. It is to provide a device.

Another object of the present invention is to provide a manufacturing method for easily manufacturing such a liquid crystal display device.

Still another object of the present invention is to provide a driving method capable of sufficiently exhibiting the characteristics of a liquid crystal display device having such a high contrast, a fast response, and an excellent viewing angle characteristic.

[0009]

According to a first aspect of the present invention, a liquid crystal layer having a negative dielectric anisotropy is sandwiched between two substrates each having an electrode, and two or more types of minute regions are formed in the liquid crystal layer. A co-existing liquid crystal display device, comprising: an opening on at least one electrode on a substrate; and a second electrode for controlling initial alignment of the liquid crystal at the position of the opening. It relates to a display device.

A second invention is a liquid crystal display device in which a liquid crystal layer having a negative dielectric anisotropy is sandwiched between two substrates each having an electrode, and two or more types of minute regions coexist in the liquid crystal layer. In addition, the present invention relates to a liquid crystal display device including at least one electrode on one substrate, which is insulated from the electrode and has a second electrode for controlling initial alignment of liquid crystal.

[0011] A third invention is the method of manufacturing a liquid crystal display device according to the first invention, comprising two substrates each having an electrode, and an electrode having an opening on at least one of the substrates. Injecting liquid crystal into an empty panel provided with a second electrode for controlling the initial alignment of liquid crystal at the position of the opening, between the electrode having the opening and the electrode facing the electrode A method of controlling the initial alignment of liquid crystal by applying a voltage higher than the voltage applied to the second electrode between the second electrode and the electrode facing the second electrode.

A fourth aspect of the present invention is the method of manufacturing a liquid crystal display device according to the second aspect of the present invention, comprising two substrates each having an electrode, wherein at least one of the substrates has an electrode and an insulating material. A step of injecting liquid crystal into an empty panel provided with a second electrode for controlling the initial alignment of the liquid crystal, which is applied between the electrode having the second electrode and the electrode facing the electrode. The present invention relates to a method for manufacturing a liquid crystal display device, comprising a step of controlling the initial alignment of liquid crystal by applying a voltage equal to or higher than a voltage between a second electrode and an electrode facing the second electrode.

According to a fifth aspect, in the method for driving a liquid crystal display device according to the first aspect, a voltage equal to or higher than a voltage applied between an electrode having an opening and an electrode opposed to the electrode is applied. The present invention relates to a method for driving a liquid crystal display device, wherein a voltage is applied between two electrodes and an electrode opposed to the two electrodes.

A sixth aspect of the present invention is the method of driving a liquid crystal display device according to the second aspect of the present invention, wherein a voltage equal to or higher than a voltage applied between an electrode having a second electrode and an electrode opposed to the second electrode is applied. ,
The present invention relates to a method for driving a liquid crystal display device, wherein a voltage is applied between a second electrode and an electrode facing the second electrode.

In the liquid crystal display device of the present invention, the liquid crystal layer can be divided into two or more types of fine regions by controlling the initial alignment of the liquid crystal by applying a voltage to the second electrode and the electrode facing the second electrode. it can. As a result, excellent viewing angle characteristics such as high contrast, fast response, and a wide viewing angle can be realized without increasing complicated steps such as a photoresist step in manufacturing.

At this time, "at the position of the opening" means that when the liquid crystal display device is viewed from the front, the opening and the second electrode are substantially at the same position and overlap. That is, when the liquid crystal display device according to the present invention is viewed as a cross section, it does not necessarily mean that there is an electrode at the same position as the opening. That is, the opening and the second electrode may be “the same layer” (FIG. 8), but may be “different layers” via the insulating film (FIG. 1). . Note that the fact that the opening and the second electrode are “in the same layer” means that, for example, as shown in FIG. 8, the opening 24 formed in the pixel electrode 22 is electrically insulated from the pixel electrode 22. The second electrode 25 is present. The term "initial alignment of liquid crystal" broadly refers to the liquid crystal alignment at the start of driving, but also refers to the initial alignment at the time of manufacturing a panel.

In the manufacturing method of the present invention, it is preferable to apply a voltage to the substrate while applying a voltage. The application of pressure is not particularly limited as long as a stress is generated in the liquid crystal layer so that the division is good. Stress may be generated in the liquid crystal layer by mechanical vibration. Accordingly, the movement of the liquid crystal molecules is accelerated, and the liquid crystal molecules move in a direction corresponding to the electric field, and accordingly, the boundary region also moves in a direction corresponding to the electric field. As a result, a good liquid crystal display device in which each pixel is completely divided at desired positions can be obtained.

Here, the pressure applied to the substrate may be a pressure enough to move the boundary of the liquid crystal, and may be applied using a large pressure machine. It may be a minute shape applied with a simple shape.
Also, whether this pressure is continuous or intermittent,
It may be periodic.

The mechanical vibration is not limited as long as it generates a stress in the liquid crystal layer such that a very small amount moves, and various types of vibration can be considered. The vibration is caused by a mechanical structure using a cam or the like. Or an acoustic wave such as an ultrasonic wave or a subsonic wave. Above all, an ultrasonic wave is desirable, but the frequency and intensity can be appropriately selected in various ways.

The liquid crystal display device of the present invention desirably has at least one optical compensator between the polarizing plate and the liquid crystal cell in order to improve the viewing angle characteristics. In this optical compensator, the liquid crystal has a homeotropic alignment when no voltage is applied. Therefore, it is preferable to use an optically negative compensator from the viewpoint of canceling a change in retardation when viewed from an oblique direction. Such a compensating plate may be a single film produced by a method such as biaxial stretching,
The same effect can be obtained even when two or more uniaxially stretched films are stacked and used as a substantially optically negative uniaxial compensator.

Further, a film having a positive optical anisotropy may be attached to the liquid crystal display device of the present invention. Although the initial alignment of the liquid crystal is vertical in principle, it can be further compensated for, for example, when the liquid crystal is deviated in a certain direction due to the characteristics of the device.

In the method of manufacturing a liquid crystal display device according to the present invention, the initial alignment of the liquid crystal is controlled by applying a predetermined voltage to the control electrode (second electrode). The initial alignment of the liquid crystal may be controlled only by applying a voltage to the control electrode at room temperature.However, after the liquid crystal layer is made isotropic by heating, the temperature is decreased while applying a voltage to the control electrode. It is preferable to carry out. Alternatively, it is preferable to control the initial alignment of the liquid crystal by applying a voltage to the control electrode, and then polymerize a small amount of the polymerizable monomer or oligomer in the liquid crystal. Further, both the temperature control and the polymerization may be performed. With these, the initial liquid crystal alignment can be further ensured.

When the initial orientation is controlled by applying a voltage to the control electrode at room temperature (when polymerizing is performed without performing temperature control), it is preferable to cause a polymerizing reaction after applying the voltage. Alternatively, a polymerization reaction may be caused before the voltage is applied. When both temperature control and polymerization are performed, the reaction of the monomer or oligomer may be caused before heating to the isotropic phase, may be caused during heating, or may be caused after cooling. You may.

Further, in the method of manufacturing a liquid crystal display device according to the present invention, the control electrode is subjected to a process of controlling the pretilt angle in accordance with the divided shape using a method such as rubbing or optical alignment on the substrate in advance. The control of the initial orientation can be extremely reliably performed. Further, by polymerizing a polymerizable monomer or oligomer mixed in a small amount in the liquid crystal, such an alignment can be prevented from being disturbed by a driving voltage, and an excellent effect can be obtained.

At this time, in the case of rubbing, divisional orientation using a photoresist is performed. In the case of optical alignment, for example, a substance having a functional group capable of controlling the alignment of liquid crystal by polarized light such as a cinnamic acid group is used for an alignment film so that a pretilt angle is obtained in a direction along a divided shape. Each part is irradiated with polarized light from an oblique direction through a mask. In addition,
Although such a split orientation method is well known, the use of a control electrode as in the present invention is much better with respect to the stability of the split. In addition, by polymerizing a polymerizable monomer or oligomer mixed in a small amount in the liquid crystal, division can be maintained more reliably even during driving.

As the monomers and oligomers used in the present invention, any of photo-curable monomers, thermo-curable monomers and oligomers thereof can be used. May be included. The photocurable monomers and oligomers used in the present invention include not only those which react with visible light but also those which react with ultraviolet rays, and the latter is particularly desirable from the viewpoint of easy operation.

The polymer compound used in the present invention is:
It may have a structure similar to liquid crystal molecules including monomers and oligomers exhibiting liquid crystallinity, but is not necessarily used for the purpose of aligning liquid crystal, and therefore has flexibility such as having an alkylene chain. You may. Further, it may be a monofunctional one, a bifunctional one, or a monomer containing a trifunctional or higher polyfunctional monomer.

The addition or formation of the polymer compound is mainly performed to stabilize the divided orientation state. When the direction in which the liquid crystal falls is defined by the control electric field, and one pixel is divided into a plurality of regions in which the liquid crystal falls in different directions, the divided states may be mixed with each other except for the control electric field.
Polymer is added or formed to prevent this and ensure division. In a broad sense, the liquid crystal is aligned, but the role of aligning the liquid crystal is mainly borne by the alignment film.

The light or ultraviolet curable monomers used in the present invention include, for example, 2-ethylhexyl acrylate, butyl ethyl acrylate, butoxyethyl acrylate, 2-cyanoethyl acrylate, benzyl acrylate, cyclohexyl acrylate, 2-hydroxypropyl acrylate, 2-hydroxypropyl acrylate, Ethoxyethyl acrylate, N, N-ethylaminoethyl acrylate, N,
N-dimethylaminoethyl acrylate, dicyclopentanyl acrylate, dicyclopentenyl acrylate, glycidyl acrylate, tetrahydrofurfuryl acrylate, isobonyl acrylate, isodecyl acrylate, lauryl acrylate, morpholine acrylate, phenoxyethyl acrylate, phenoxydiethylene glycol acrylate, 2, 2,2,3-trifluoroethyl acrylate, 2,2,3,3,3-pentafluoropropyl acrylate, 2,2,3,3
-Tetrafluoropropyl acrylate, 2,2,3
Monofunctional acrylate compounds such as 4,4,4, -hexafluorobutyl acrylate can be used.

Further, 2-ethylhexyl methacrylate, butylethyl methacrylate, butoxyethyl methacrylate, 2-cyanoethyl methacrylate, benzyl methacrylate, cyclohexyl methacrylate,
-Hydroxypropyl methacrylate, 2-ethoxyethyl acrylate, N, N-diethylaminoethyl methacrylate, N, N-dimethylaminoethyl methacrylate, dicyclopentanyl methacrylate, dicyclopentenyl methacrylate, glycidyl methacrylate,
Tetrahydrofurfuryl methacrylate, isobonyl methacrylate, isodecyl methacrylate, lauryl methacrylate, morpholine methacrylate, phenoxyethyl methacrylate, phenoxydiethylene glycol methacrylate, 2,2,2-trifluoroethyl methacrylate, 2,2,3,3-tetrafluoropropyl methacrylate And monofunctional methacrylate compounds such as 2,2,3,4,4,4-hexafluorobutyl methacrylate.

Further, 4,4'-biphenyl diacrylate, diethylstilbestrol diacrylate,
1,4-bisacryloyloxybenzene, 4,4′-
Bisacryloyloxydiphenyl ether, 4,4 '
-Bisacryloyloxydiphenylmethane, 3,9-
Bis [1,1-dimethyl-2-acryloyloxyethyl] -2,4,8,10-tetraspiro [5,5] undecane, α, α′-bis [4-acryloyloxyphenyl] -1,4-diisopropyl Benzene, 1,4-bisacryloyloxytetrafluorobenzene, 4,
4'-bisacryloyloxyoctafluorobiphenyl, diethylene glycol diacrylate, 1,4-butanediol diacrylate, 1,3-butylene glycol diacrylate, dicyclopentanyl diacrylate, glycerol diacrylate, 1,6-hexanediol diacrylate Acrylate, neopentyl glycol diacrylate, tetraethylene glycol diacrylate,
Trimethylolpropane triacrylate, pentaerythritol tetraacrylate, pentaerythritol triacrylate, ditrimethylolpropane tetraacrylate, dipentaerythritol hexaacrylate, dipentaerythritol monohydroxypentaacrylate, 4,4'-diacryloyloxystilbene, 4,4 ' -Diacryloyloxydimethylstilbene, 4,4'-diacryloyloxydiethylstilbene, 4,4'-diacryloyloxydipropylstilbene, 4,4'-diacryloyloxydibutylstilbene, 4,4'-diacryloyloxydipentyl Stilbene, 4,4'-diacryloyloxydihexylstilbene, 4,4'-diacryloyloxydifluorostilbene, 2,2,3,3 , 4-hexafluoro-pentanediol-1,5 diacrylate, 1,1,
2,2,3,3-hexafluoropropyl-1,3-
Polyfunctional acrylate compounds such as diacrylate and urethane acrylate oligomer can be used.

Furthermore, diethylene glycol dimethacrylate, 1,4-butanediol dimethacrylate, 1,3-butylene glycol dimethacrylate, dicyclopentanyl dimethacrylate, glycerol dimethacrylate, 1,6-hexanediol dimethacrylate, neopentyl Glycol dimethacrylate, tetraethylene glycol dimethacrylate, trimethylolpropane trimethacrylate, pentaerythritol tetramethacrylate, pentaerythritol trimethacrylate, ditrimethylolpropane tetramethacrylate, dipentaerythritol hexamethacrylate, dipentaerythritol monohydroxypentamethacrylate, 2,2 3,3,4,4-hexafluoropentanediol-1 5-dimethacrylate, polyfunctional methacrylate compounds such as urethane methacrylate oligomer, other styrene, amino styrene, there are vinyl acetate, but is not limited thereto.

The driving voltage of the device of the present invention is also affected by the interfacial interaction between the polymer material and the liquid crystal material. Therefore, a polymer compound containing elemental fluorine may be used. Examples of such a polymer compound include 2,2,3,3,4,4-hexafluoropentanediol-1,5-diacrylate, 1,1,2,2,3,3-hexafluoropropyl-1, 3-diacrylate, 2,2,2-trifluoroethyl acrylate, 2,2,3,3,3-pentafluoropropyl acrylate, 2,2,3,3-tetrafluoropropyl acrylate, 2,2,3 4,4,4
-Hexafluorobutyl acrylate, 2,2,2-trifluoroethyl methacrylate, 2,2,3,3-tetrafluoropropyl methacrylate, 2,2,3
Examples include, but are not limited to, polymer compounds synthesized from compounds including 4,4,4-hexafluorobutyl methacrylate, urethane acrylate oligomers, and the like.

When a light or ultraviolet curable monomer is used in the polymerization reaction in the present invention, an initiator for light or ultraviolet light can be used. As the initiator, various initiators can be used.
-Diethoxyacetophenone, 2-hydroxy-2-methyl-1-phenyl-1-one, 1- (4-isopropylphenyl) -2-hydroxy-2-methylpropane-
Acetophenones such as 1-one, 1- (4-dodecylphenyl) -2-hydroxy-2-methylpropan-1-one, benzoin-based such as benzoin methyl ether, benzoin ethyl ether, and benzyldimethyl ketal;
Benzophenones such as benzophenone, benzoylbenzoic acid, 4-phenylbenzophenone and 3,3-dimethyl-4-methoxybenzophenone; thioxanthone;
Thioxanthone, such as chlorothioxanthone and 2-methylthioxanthone, diazonium salt, sulfonium salt, iodonium salt, and selenium salt can be used.

[0035]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be specifically described below.

(Embodiment 1) As shown in FIG. 1, a liquid crystal display device of the present invention has a negative dielectric anisotropy between two substrates 23 and 33 having electrodes 22 and 32, respectively. A layer made of certain liquid crystal molecules 11 is sandwiched. Vertical alignment films 21 and 31 are applied to each electrode, and rubbed as necessary. Also, one substrate 23
The electrode 22 has an opening 24, and an electrode 25 for controlling the initial alignment of the liquid crystal is provided at the same position as the opening 24. Different voltages are applied to the electrode 22 and the second electrode 25. You can call it.

When the opening 24 and the second electrode 25 are not provided as in the conventional liquid crystal display device, the direction in which the liquid crystal molecules fall (the direction in which the liquid crystal molecules tilt) when a voltage is applied.
Is random when the alignment film is not rubbed, and coincides with the rubbing direction when rubbed. On the other hand, in the liquid crystal display device of the present invention,
Since there is a second electrode 25 for controlling the initial alignment of the liquid crystal in addition to the electrode 22, for example, the electrode 22 and the electrode 3
By applying a voltage higher than the voltage applied to 2 between the second electrode 25 and the electrode 32, a non-uniform electric field is generated in the liquid crystal layer. Therefore, the liquid crystal molecules 11 fall in a direction along the non-uniform electric field as shown in FIG.

The same behavior of the liquid crystal can be realized by using an electrode provided with an opening as in the conventional example of FIG. However, in the prior art, since there is no electrode at the opening 34 as shown in FIG.
Even when a voltage is applied to No. 2, a sufficient electric field is not applied to this portion, and the liquid crystal does not respond sufficiently to the applied voltage.

Further, it has been found that a desired effect cannot be obtained simply by providing an opening when driving with an active element. That is, in the case of a generally manufactured active element, the electrode on the color filter side (usually referred to as “common electrode”) does not require a photoresist process, and the electrode is formed on the entire surface.
On the active element side substrate, a switching element is formed for each pixel, and pixel electrodes are independently provided. In such a device, it is necessary to open an opening in the common electrode in order to generate a non-uniform electric field due to the difference in size between the upper and lower electrodes, and to divide and tilt the liquid crystal by the effect. FIG. 7A shows a cross section when an opening is formed in the common electrode, and FIG. 7B shows a cross section when an opening is formed in the electrode on the active element side. As is clear from FIG. 7B, when the electrode 22 on the active element side is small,
Unless an opening is provided on the common electrode side, there is a portion that tilts in the opposite direction and a portion in which a non-uniform electric field does not occur, and in this portion, disclination occurs and the tilt direction of the liquid crystal molecules is changed. A desired orientation cannot be obtained, for example, cannot be defined, and as a result, a uniform display cannot be obtained. However, providing an opening in the common electrode requires a photoresist process on the common electrode side. For this reason, the number of photoresist steps that are not required in a normal liquid crystal display device increases, leading to a decrease in yield and an increase in price.

When an opening is provided in a pixel electrode on the active element side as in the present invention, only the mask is changed, and the number of photoresist steps is not increased. Also, with this alone,
Since there is a disadvantage that a non-uniform electric field does not occur due to the difference in size between the upper and lower electrodes, a second electrode for controlling liquid crystal alignment is provided in the opening, and a voltage is applied to the second electrode to generate a non-uniform electric field. . This situation is shown by a broken line in FIG.

The second electrode for controlling the liquid crystal alignment can be formed as a separate layer from an electrode layer such as a signal device and a drain line in manufacturing an active element. It is desirable to make. Thus, a desired non-uniform electric field can be formed only by changing the mask without increasing the number of photoresist steps. For example, the use of an electrode layer constituting a gate electrode layer as a second electrode layer can be given. Note that the effect remains the same whether the second electrode is in the opening or at the same position as the opening through the insulating layer.

The shape of the control electrode (second electrode) in the present invention is basically an X type as shown in FIG. 4A, but is parallel to one side of the pixel as shown in FIG. 4B. It is desirable from the viewpoint of division that a shape in which two Y-shaped portions having different portions are connected, or a shape in which two T-shaped portions are connected as shown in FIG. These shapes need not be straight,
As shown in FIGS. 4D and 4E, it may be constituted by a curve. Furthermore, the smaller the division unit is, the more effectively the control electric field works. Therefore, as shown in FIGS.
A shape having a plurality of molds is more preferable. The linear electrode between the X-type electrodes may be connected to another control electrode portion as a control electrode or may be floating. In the figure, for convenience, the control electrodes of each pixel are depicted as being independent, but they are actually connected so that a voltage can be applied collectively from an extraction terminal at the end of the panel.

Further, in the active element, an electric field which is to be split in the horizontal direction of a vertically long pixel works due to the influence of the horizontal electric field from the signal line, and therefore, FIG.
As shown in (a), when the control electrode is inserted vertically, the electric field from the control electrode and the horizontal electric field work cooperatively, so that the division is properly performed. In addition, since the shape of the pixel is not completely symmetric due to the presence of the active element, FIG.
The division may be asymmetric as shown in FIG.

Further, in the liquid crystal display device of the present invention, a portion (opening) where the pixel transparent electrode 22 does not exist above the control electrode 25 so that an electric field is generated obliquely between the control electrode 25 and the common electrode 32. 24),
The width of this portion is preferably smaller than the width of the control electrode from the viewpoint of preventing light leakage. Also, the portion (opening) where the pixel transparent electrode does not exist does not necessarily have to coincide with the entire control electrode, and may be partially cut out as shown in FIG. As shown in e), there may be a portion where the pixel transparent electrode does not exist in a portion other than the control electrode.

In a further preferred embodiment of the present invention, a liquid crystal cell having a structure as shown in FIG.
This is realized by heating the cell above the liquid crystal isotropic phase-liquid crystal phase transition temperature and cooling it to a temperature below the isotropic phase-liquid crystal layer transition temperature while applying a voltage to the control electrode 25 and the counter electrode 32. . By this operation, the control of the initial alignment of the liquid crystal is performed more uniformly.

In still another embodiment of the present invention, a liquid crystal cell having a structure as shown in FIG. 1 is manufactured, a liquid crystal containing a small amount of monomer or oligomer is injected, and a voltage is applied to the control electrode 25 and the counter electrode 32. While the monomer or oligomer is polymerized by light or heat. This allows
The initial alignment of the liquid crystal becomes stronger, and the liquid crystal becomes more resistant to physical shocks during use.

In this polymerizing step, the cell is heated to a temperature equal to or higher than the isotropic phase-liquid crystal phase transition temperature of the liquid crystal while applying a voltage to the control electrode 25 and the counter electrode 32, as necessary, as described above. Cooled to a temperature below the isotropic phase-liquid crystal layer transition temperature,
It may be performed after the alignment of the liquid crystal is sufficiently uniform.

Further, a liquid crystal cell using a substrate which has been subjected to a normal division alignment treatment such as changing the rubbing direction or irradiating polarized light obliquely is manufactured in a form according to the structure of the control electrode. When a voltage is applied to the counter electrode 32,
The division boundary can be fixed firmly over the entire panel, and the reliability is greatly improved. At this time, the reliability is further improved by using a liquid crystal containing a monomer or an oligomer, forming a divided state, and then polymerizing the liquid crystal. In this case, as the alignment film, a normal vertical alignment film can be used in the case of rubbing, and in the case of irradiating polarized light obliquely, for example, a digest of technical papers of AMLC 96 / ID-W'96 can be used. (AM-LCD'96 / IDW'96 Di
gestof Technical Papers)
P. 337, a polymer in which a photosensitive group is polymerized by irradiation with polarized light can be used.

(Embodiment 2) According to still another embodiment of the present invention, the second electrode for controlling the initial alignment of the liquid crystal has an insulating film on one of the electrodes for driving the liquid crystal. It exists through. FIG. 2 shows this structure.

Also in this case, in the case of a liquid crystal display device which drives liquid crystal using active elements, the initial orientation of liquid crystal is controlled on the electrode of the substrate on the side where the active element is located, based on the shape of the electrodes. Is desirably present. Also in this case, if the form of the active element is selected, the number of photolithography steps is not increased, and at the time of driving, there is no portion to which voltage is not applied in the pixel as compared with the case where the opening is simply provided.
An image excellent in terms of contrast and aperture ratio can be obtained.

Also in this case, after injecting the liquid crystal,
While applying a voltage to the second electrode 25 for controlling the initial alignment of the liquid crystal and the electrode 32 of the counter substrate, the liquid crystal phase of the liquid crystal is reduced.
When the liquid crystal is heated to a temperature higher than the isotropic phase transition temperature and cooled to a temperature lower than the liquid crystal phase-isotropic phase transition temperature, the orientation of the liquid crystal becomes more reliable.

Also, exactly as in the first embodiment,
Mix a small amount of monomer or oligomer in the liquid crystal,
By applying a voltage to the second electrode 25 for controlling the initial alignment of the liquid crystal and the electrode 32 of the counter substrate, and polymerizing the monomer or oligomer by light or heat,
The orientation of the liquid crystal becomes stronger, and the occurrence of disclination and the like can be suppressed more reliably even during driving.

Further, by using a substrate that has been subjected to divisional alignment along the shape of the second electrode by rubbing, optical alignment, or the like, the orientation of the liquid crystal during the division and driving of the liquid crystal becomes stronger, The occurrence of disclination and the like can be further suppressed.

By performing the above-described temperature control, polymerizing, rubbing, or photo-alignment treatment in combination or any of them, it is possible to more reliably regulate the alignment and obtain excellent image quality.

[0055]

Next, the present invention will be described in detail with reference to examples.

(Example 1) Size of one pixel: 100 μm
A substrate having an amorphous silicon thin film transistor array (TFT) having a size of × 300 μm, the number of pixels: 480 × 640 × 3, and the diagonal size of a display screen: 240 mm was formed on a glass substrate by repeating a film formation process and a lithography process.

The TFT according to the first embodiment has an inverted staggered structure. From the substrate side, a gate-chromium layer, a silicon nitride-insulating layer, an amorphous silicon-semiconductor layer, a drain-source-chromium layer, a pixel-ITO (Indium Tin) Oxide) layer. In the ITO layer of each of the prepared pixel electrodes, an “X” -shaped opening having a width of 5 μm is provided in a diagonal direction,
A second electrode of “X” shape was made of chromium so as to coincide with this opening. The second electrode was designed so that a voltage different from that of the pixel portion could be externally applied. Since the second electrode was made of chromium in the same layer as the gate electrode, it was not necessary to add a new process as compared with the conventional manufacturing process. In addition, an RGB color filter substrate was used as a counter substrate for manufacturing a liquid crystal panel in Embodiment 1 (the basic configuration of this embodiment is shown in FIG.
reference).

After washing these substrates, a polyimide vertical alignment agent: SE1211 (trade name, manufactured by Nissan Chemical Industries, Ltd.) was applied and baked at 90 ° C. for 15 minutes and at 200 ° C. for 1 hour. , 31 were formed.

Thereafter, an adhesive is applied to the periphery of the substrate,
Latex balls having a diameter of 6 μm were sprayed as spacers. Subsequently, both substrates were aligned and bonded together under pressure. The bonded plate (empty panel) was placed in a vacuum chamber, and after evacuation, a nematic liquid crystal having a negative dielectric anisotropy (trade name: MJ95955, manufactured by Merck Ltd.) was injected. The liquid crystal had a refractive index anisotropy Δn of 0.0773 and a dielectric anisotropy Δε of −3.3.

Next, two stretched films made of polycarbonate are adhered to the obtained liquid crystal panel so that the stretching axes are orthogonal to each other, and a film having a substantially optically uniaxial negative anisotropy is obtained. Δnd (retardation) is Δ of the liquid crystal cell.
nd and the sign were set to be opposite and equal to each other, and attached to the outer surface of the substrate 33 of the liquid crystal panel. Further, two polarizing films were stuck on both sides of the liquid crystal panel so that the transmission axes were orthogonal to each other, to obtain a liquid crystal display device. Note that Δn
Represents the refractive index anisotropy of the material, is the difference between the refractive index in the direction parallel to the molecular long axis and the refractive index in the direction perpendicular to the molecular long axis, and d is the thickness.

A voltage of 8 V was applied to the "X" shaped electrode of the obtained liquid crystal display device with respect to the counter electrode, and display was performed in the same manner as usual. The pixel display voltage was about 5.5V. As a result, it was found that the liquid crystal display device of this example did not have gradation inversion in any direction and provided excellent images.

Comparative Example 1 For comparison, the liquid crystal display device used in Example 1 was driven in the same manner as in Example 1 except that the liquid crystal display was driven without applying a voltage to the “X” shaped electrode. I let it. In Comparative Example 1, tone inversion occurred and many afterimages were observed. When observed with a microscope, it was observed that disclination was generated in each pixel and changed over time immediately after voltage application.

Example 2 A display panel was manufactured in the same manner as in Example 1 except that a TFT having a staggered structure was manufactured as a TFT substrate. Size of one pixel: 100μ
A substrate having an amorphous silicon thin film transistor array (TFT) of m × 300 μm, the number of pixels: 480 × 640 × 3, and the diagonal size of the display screen: 240 mm was formed on a glass substrate by repeating the film formation process and the lithography process. .

The TFT according to the second embodiment has a forward staggered structure and is composed of a pixel-ITO layer, a source / drain-chromium layer, an amorphous silicon-semiconductor layer, a silicon nitride-insulating layer, and a gate-chromium layer from the substrate side. Have been.
The ITO layer of each of the prepared pixel electrodes has a width of 5 μm in a diagonal direction.
An “X” -shaped opening of m was provided, and an “X” -shaped electrode was made of chromium so as to coincide with the opening. This electrode was designed so that a voltage different from that of the pixel portion could be externally applied. (Because this electrode was made of chromium in the same layer as the gate electrode, there was no need to add a new process as compared with the conventional manufacturing process.) Thereafter, the panel was formed in the same manner as in Example 1. The liquid crystal display was fabricated by assembling and injecting liquid crystal.

A voltage of 8 V was applied to the “X” -shaped electrode of the obtained liquid crystal display device with respect to the counter electrode, and display was performed in the same manner as usual. The pixel display voltage was about 5V. As a result, it was found that the liquid crystal display device of the second embodiment also provided excellent images without gradation inversion in any direction, similarly to the first embodiment.

Comparative Example 2 For the purpose of comparison, the same procedure as in Example 2 was performed except that no voltage was applied to the “X” -shaped electrode when the voltage was applied.
The device was driven in the same manner as described above. The divided state of the four regions was irregular, and roughness was visually observed in the oblique direction.

(Example 3) A TFT substrate was produced in the same manner as in Example 1, and an empty panel was produced by combining this substrate with a color filter substrate. The bonded substrate (empty panel) is placed in a vacuum chamber, and after evacuation, a nematic liquid crystal having a negative dielectric anisotropy (trade name: MJ95, manufactured by Merck Ltd.)
955), an ultraviolet-curing monomer (manufactured by Nippon Kayaku Co., Ltd., trade name: KAYARAD PET-30) (0.2 wt% based on the liquid crystal), and an initiator (benzoin methyl ether manufactured by Tokyo Kasei, 5 wt% based on the monomer). Liquid crystal solution was injected.

The obtained display panel was heated to 110 ° C. and irradiated with ultraviolet rays (0.1 mW / cm ² ) at that temperature for 30 minutes. Then, 10V, 5H is applied to the "X" shaped electrode.
The substrate was cooled at 20 ° C./min while applying a sine wave voltage of z and a sine wave voltage of 5 V and 5 Hz to the pixel.

When the obtained cell was observed with a polarizing microscope,
Each section was divided into four minute regions according to the “X” -shaped electrode. From the change in brightness when the cell is tilted,
It was confirmed that the four minute regions had the orientation shown in FIG.

An optical compensator and a polarizing plate were attached, and the voltage of the “X” -shaped electrode of the obtained liquid crystal display was turned off, and the display was performed in a normal state. Even in the halftone, good display was obtained with a wide viewing angle in which no grayscale inversion occurred. In addition, a liquid crystal evaluation device (manufactured by Otsuka Electronics Co., Ltd., trade name: LCD-500)
When the viewing angle characteristics during gradation display were measured at an azimuth angle of 45 ° at 0), almost the same viewing angle characteristics were obtained in all directions, and no gradation inversion was observed.

Example 4 An empty panel was prepared in the same manner as in Example 3, and a mixture of liquid crystal, an ultraviolet curable monomer and an initiator was injected. At room temperature, a rectangular wave voltage of 40 V and 1 Hz was applied to the "X" -shaped electrode at room temperature, and the pixel electrode, drain line, and gate line of the opposing substrate were kept at 0 V. In this state, ultraviolet rays (0.1 mW / cm ² ) were irradiated from a high-pressure mercury lamp for 1 hour.

When the obtained cell was observed with a polarizing microscope,
Each section followed an “X” shaped electrode, and the liquid crystal layer was divided into four small regions. From the change in brightness when the cell was tilted, it was confirmed that the four minute regions had the orientation shown in FIG.

An optical compensator and a polarizing plate were attached, and the voltage of the “X” -shaped electrode of the obtained liquid crystal display was turned off, and the display was performed in a normal state. As a result, even in halftones,
Good display was obtained at a wide viewing angle where no grayscale inversion occurred. In addition, a liquid crystal evaluation device (LCD-5000: trade name)
When the viewing angle characteristics at the time of gradation display were measured at an azimuth angle of 45 °, almost the same viewing angle characteristics were obtained in all directions, and no gradation inversion was observed.

(Embodiment 5) The shape of the opening is rectangular as shown in FIG. 3, the opening 24 is set at the center of the pixel in the same manner as in Embodiment 4, and the control electrode 25 having a "-" shape is provided. A liquid crystal display device was manufactured. A rectangular wave voltage in the state of 40 V and 1 Hz is applied to the control electrode having a “−” shape in the same manner as in the fourth embodiment, and the pixel electrode, the drain line, and the gate line of the counter substrate are set to 0.
Kept at V. In this state, ultraviolet rays (0.
1 mW / cm ² ) for 1 hour.

When the obtained cell is observed with a polarizing microscope,
Each section was divided into two minute regions according to the “−” shaped electrode. From the change in brightness when the cell is tilted,
It was confirmed that the two minute regions had a liquid crystal orientation as shown in FIG.

An optical compensator and a polarizing plate were attached, and the voltage of the "-" shaped electrode of the obtained liquid crystal display was turned off, and the display was performed in a normal state. Even in the halftone, good display was obtained with a wide viewing angle in which no grayscale inversion occurred. Further, an azimuth angle of 4 degrees was measured using a liquid crystal evaluation device (LCD-5000: trade name).
When the viewing angle characteristics of gradation display were measured at 5 ° intervals, almost the same viewing angle characteristics were obtained in all directions, and no gradation inversion was observed. (Example 6) An empty panel was prepared in the same manner as in Example 2, and a mixture of liquid crystal, an ultraviolet curable monomer and an initiator was injected in the same manner as in Example 4, and the monomer was cured with ultraviolet light.

When the obtained cell was observed with a polarizing microscope,
According to the electrode of each section “X” shape, it was divided into four minute regions. From the change in brightness when the cell is tilted, 4
It was confirmed that the two micro regions had the orientation shown in FIG.

An optical compensator and a polarizing plate were attached, and the voltage of the “X” -shaped electrode of the obtained liquid crystal display was turned off, and the display was performed in a normal state. Even in the halftone, good display was obtained with a wide viewing angle in which no grayscale inversion occurred. Further, an azimuth angle of 4 degrees was measured using a liquid crystal evaluation device (LCD-5000: trade name).
When the viewing angle characteristics at the time of gradation display were measured at intervals of 5 °, almost the same viewing angle characteristics were obtained in all directions, and no gradation inversion was observed.

Example 7 A substrate having a TFT similar to that of Example 1 was used, and a polyimide vertical alignment agent was applied thereto.
After baking, only the substrate on the TFT element side is divided by rubbing so that the direction in which the liquid crystal tilts and the rubbing direction when the voltage is applied to the control electrode is applied to each part in the pixel using the photoresist process. Was given. Thereafter, a spacer agent was sprinkled in the same manner as in Example 1, the two substrates were bonded together, and after injecting liquid crystal, a compensator and a polarizing film were bonded to prepare a liquid crystal display device.

A voltage of 8 V was applied to the “X” -shaped electrode of the obtained liquid crystal display device with respect to the counter electrode, and a display was performed in the same manner as usual. The pixel display voltage was about 5.5V. As a result, it was found that the liquid crystal display device of this example did not have gradation inversion in any direction and provided excellent images. No disclination was observed.

Example 8 An empty panel was prepared in the same manner as in Example 4, and a mixture of liquid crystal, an ultraviolet curable monomer and an initiator was injected into the empty panel. Next, while applying a voltage in the same manner as in Example 4, pressure was applied to the entire surface of the panel using a roller.

In exactly the same manner as in Example 4, the obtained cell was observed with a polarizing microscope, and an optical compensator and a polarizing plate were attached to perform display.

As a result, similarly to the fourth embodiment, each section was divided into four minute areas according to the “X” -shaped electrodes. In addition, in Example 4, there was no bending at the division boundary observed in some pixels. Further, good display was obtained with a wide viewing angle in which no gradation inversion occurred in all directions.

Example 9 An empty panel was prepared in the same manner as in Example 2, and a mixture of liquid crystal, an ultraviolet curable monomer and an initiator was injected into this empty panel in the same manner as in Example 4. Next, while applying a voltage in the same manner as in Example 4, an ultrasonic transmitter was applied to the panel surface, and scanning was performed over the entire surface. Thereafter, ultraviolet irradiation was performed in the same manner as in Example 4.

In exactly the same manner as in Example 4, the obtained cell was observed with a polarizing microscope, and an optical compensator and a polarizing plate were attached to perform display.

As a result, as in the case of the fourth embodiment, each section was divided into four minute areas according to the "X" -shaped electrodes. In addition, in Example 4, there was no bending at the division boundary observed in some pixels. Further, good display was obtained with a wide viewing angle in which no gradation inversion occurred in all directions.

[0087]

As described above, according to the present invention, it is possible to provide a liquid crystal display device having high contrast, quick response, and excellent viewing angle characteristics, and to form an excellent image using this liquid crystal display device. be able to. Further, this liquid crystal display device can be easily manufactured at low cost without increasing complicated steps such as a photoresist step.

[Brief description of the drawings]

FIG. 1 is a sectional view of a liquid crystal display device of the present invention.

FIG. 2 is a sectional view of another embodiment of the liquid crystal display device of the present invention.

FIG. 3 is a schematic plan view of a lower substrate of one pixel of the liquid crystal display device of the present invention.

FIG. 4 is a schematic plan view of a lower substrate of one pixel of the liquid crystal display device of the present invention.

FIG. 5 is a schematic plan view of a lower substrate of one pixel of the liquid crystal display device of the present invention.

FIG. 6 is an explanatory diagram of a conventional liquid crystal display device.

FIG. 7 is a sectional view showing a conventional liquid crystal display device.

FIG. 8 is a sectional view of another embodiment of the liquid crystal display device of the present invention.

[Explanation of symbols]

 Reference Signs List 11 liquid crystal molecule 21, 31 alignment film 22, 32 transparent electrode 23, 33 substrate 24, 34 opening 25 control electrode (second electrode) 26 insulating film

────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] December 18, 1997

[Procedure amendment 1]

[Document name to be amended] Drawing

[Correction target item name] Fig. 1

[Correction method] Change

[Correction contents]

FIG.

[Procedure amendment 2]

[Document name to be amended] Drawing

[Correction target item name] Figure 2

[Correction method] Change

[Correction contents]

FIG. 2

[Procedure amendment 3]

[Document name to be amended] Drawing

[Correction target item name] Fig. 6

[Correction method] Change

[Correction contents]

FIG. 6

[Procedure amendment 4]

[Document name to be amended] Drawing

[Correction target item name] Fig. 7

[Correction method] Change

[Correction contents]

FIG. 7 ────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] October 14, 1998

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0003

[Correction method] Change

[Correction contents]

As a method for improving the viewing angle characteristics of a liquid crystal display device, Japanese Patent Application Laid-Open No. 4-261522 or Japanese Patent Application Laid-Open
A technique as disclosed in Japanese Patent No. 43461 is proposed. In these techniques, a homeotropically aligned liquid crystal cell is manufactured, sandwiched between two polarizing plates arranged so that the polarization axes are orthogonal to each other, and a common electrode 32 having an opening 34 is used as shown in FIG. By doing so, an oblique electric field is generated in each pixel, whereby each pixel is divided into two or more liquid crystal domains, and the viewing angle characteristics are improved.
In Japanese Patent Application Laid-Open No. Hei 4-261522, high contrast is realized by controlling the direction in which the liquid crystal is inclined when a voltage is applied. Also, JP-A-6-4346.
As described in Japanese Patent Application Publication No. 1 (1999) -1995, an optical compensator is used as necessary to improve the viewing angle characteristics of black. further,
In JP-A-6-43461, each pixel is divided into two or more domains by an oblique electric field to improve the viewing angle characteristics not only in a homeotropically aligned liquid crystal cell but also in a TN aligned cell. I have.

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0019

[Correction method] Change

[Correction contents]

The mechanical vibration is not limited as long as a stress such that a minute area moves is generated in the liquid crystal layer. Various types of mechanical vibration can be considered, and the mechanical vibration is caused by a mechanical structure using a cam or the like. Alternatively, a sound wave such as an ultrasonic wave or a subsonic wave may be used. Above all, an ultrasonic wave is desirable, but the frequency and intensity can be appropriately selected in various ways.

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name] 0022

[Correction method] Change

[Correction contents]

In the method of manufacturing a liquid crystal display device according to the present invention, the initial alignment of the liquid crystal is controlled by applying a predetermined voltage to the control electrode (second electrode). The initial alignment of the liquid crystal may be controlled only by applying a voltage to the control electrode at room temperature.However, after the liquid crystal layer is made isotropic by heating, the temperature is decreased while applying a voltage to the control electrode. It is preferable to carry out. Alternatively, it is preferable to control the initial alignment of the liquid crystal by applying a voltage to the control electrode, and then polymerize a small amount of the polymerizable monomer or oligomer in the liquid crystal. Further, both the temperature control and the polymerization may be performed . With these, the initial liquid crystal alignment can be further ensured.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0037

[Correction method] Change

[Correction contents]

When the opening 24 and the second electrode 25 are not provided as in the conventional liquid crystal display device, the direction in which the liquid crystal molecules fall (the direction in which the liquid crystal molecules tilt) when a voltage is applied.
Is random when the alignment film is not rubbed, and coincides with the rubbing direction when rubbed. On the other hand, in the liquid crystal display device of the present invention,
Since there is a second electrode 25 for controlling the initial alignment of the liquid crystal in addition to the electrode 22, for example, the electrode 22 and the electrode 3
By applying a voltage larger than the voltage applied to 2 between the second electrode 25 and the electrode 32, an oblique electric in the liquid crystal layer
A world arises. Therefore, the liquid crystal molecules 11 fall in the direction along the oblique electric field as shown in FIG.

[Procedure amendment 5]

[Document name to be amended] Statement

[Correction target item name] 0039

[Correction method] Change

[Correction contents]

Further, it has been found that a desired effect cannot be obtained simply by providing an opening when driving with an active element. That is, in the case of a generally manufactured active element, the electrode on the color filter side (usually referred to as “common electrode”) does not require a photoresist process, and the electrode is formed on the entire surface.
On the active element side substrate, a switching element is formed for each pixel, and pixel electrodes are independently provided. In the element having such a configuration, an oblique electric field is generated due to the difference in size between the upper and lower electrodes, and in order to divide and tilt the liquid crystal by the effect, it is indispensable to open an opening in the common electrode. FIG. 7A shows a cross section when an opening is formed in the common electrode, and FIG. 7B shows a cross section when an opening is formed in the electrode on the active element side. As is clear from FIG. 7 (b), when the electrode 22 on the active element side is small, unless an opening is provided on the common electrode side, a portion that tilts in reverse and a portion where an oblique electric field does not occur therebetween are formed. In such a portion, a desired orientation cannot be obtained, for example, disclination occurs, a tilt direction of liquid crystal molecules cannot be specified, and as a result, a uniform display cannot be obtained. However, providing an opening in the common electrode requires a photoresist process on the common electrode side. For this reason, the number of photoresist steps that are not required in a normal liquid crystal display device increases, leading to a decrease in yield and an increase in price.

[Procedure amendment 6]

[Document name to be amended] Statement

[Correction target item name] 0040

[Correction method] Change

[Correction contents]

When an opening is provided in a pixel electrode on the active element side as in the present invention, only the mask is changed, and the number of photoresist steps is not increased. Also, with this alone,
Since there is a drawback that a portion where an oblique electric field is not generated is formed, a second electrode for controlling liquid crystal alignment is provided in the opening, and a voltage is applied to the second electrode to generate an oblique electric field . This situation is shown by a broken line in FIG.

[Procedure amendment 7]

[Document name to be amended] Statement

[Correction target item name] 0041

[Correction method] Change

[Correction contents]

The second electrode for controlling the liquid crystal alignment can be formed as a separate layer from the electrode layers such as the signal line and the drain line when manufacturing the active element. It is desirable to manufacture with. Thus, a desired oblique electric field can be formed only by changing the mask without increasing the number of photoresist steps. For example, the use of an electrode layer constituting a gate electrode layer as a second electrode layer can be given. In addition, even if the second electrode is in the opening,
The effect remains the same even if it is located at the same position as the opening via the insulating layer.

[Procedure amendment 8]

[Document name to be amended] Statement

[Correction target item name] 0044

[Correction method] Change

[Correction contents]

Further, in the liquid crystal display device of the present invention, a portion (opening) where the pixel transparent electrode 22 does not exist above the control electrode 25 so that an electric field is generated obliquely between the control electrode 25 and the common electrode 32. 24),
The width of this portion is preferably smaller than the width of the control electrode from the viewpoint of preventing light leakage. Also, the portion (opening) where the pixel transparent electrode does not exist does not necessarily need to coincide with the entire control electrode, and may be partially cut as shown in FIG. As shown in e), there may be a portion where the pixel transparent electrode does not exist in a portion other than the control electrode.

[Procedure amendment 9]

[Document name to be amended] Statement

[Correction target item name] 0081

[Correction method] Change

[Correction contents]

Example 8 An empty panel was prepared in the same manner as in Example 4, and a mixture of liquid crystal, an ultraviolet curable monomer and an initiator was injected into the empty panel. Next, while applying a voltage in the same manner as in Example 4, pressure was applied to the entire surface of the panel using a roller. Thereafter, ultraviolet light was applied.

[Procedure amendment 10]

[Document name to be amended] Drawing

[Correction target item name] Fig. 8

[Correction method] Change

[Correction contents]

FIG. 8

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification symbol FI G09F 9/35 305 G09F 9/35 305 (72) Inventor Yoshihiko Hirai NEC Corporation, 7-5-1 Shiba, Minato-ku, Tokyo NEC Corporation Within the company (72) Kazumi Kobayashi 5-7-1 Shiba, Minato-ku, Tokyo NEC Corporation (72) Hiroaki Matsuyama 5-7-1 Shiba, Minato-ku, Tokyo NEC Corporation (72) Inventor Daisuke Inoue 5-7-1 Shiba, Minato-ku, Tokyo Within NEC Corporation

Claims (19)

[Claims] 1. A liquid crystal display device in which a liquid crystal layer having negative dielectric anisotropy is sandwiched between two substrates each having an electrode, and two or more types of minute regions coexist in the liquid crystal layer. A liquid crystal display device having an opening on an electrode on one substrate, and a second electrode at the position of the opening for controlling initial alignment of liquid crystal. 2. A liquid crystal display device in which a liquid crystal layer having a negative dielectric anisotropy is sandwiched between two substrates each having an electrode, and two or more types of minute regions coexist in the liquid crystal layer. An electrode on one substrate is insulated from this electrode,
A liquid crystal display device comprising a second electrode for controlling initial alignment of liquid crystal. 3. The liquid crystal display device according to claim 1, wherein two or more types of minute regions having different tilt directions of liquid crystal molecules coexist in the liquid crystal layer. 4. The liquid crystal display device according to claim 1, wherein the second electrode is provided on a diagonal line of each pixel. 5. The liquid crystal display device according to claim 1, wherein the second electrode has a portion parallel to the long side of each pixel. 6. The liquid crystal display device according to claim 1, further comprising at least one optical compensator between the polarizing plate and the substrate having the liquid crystal layer interposed therebetween. 7. The method for manufacturing a liquid crystal display device according to claim 1, further comprising: two substrates each having an electrode, wherein at least one of the substrates has an electrode having an opening, Injecting liquid crystal into an empty panel provided with a second electrode for controlling the initial alignment of liquid crystal at the position of the part, a voltage applied between the electrode having an opening and the electrode facing the electrode A method for manufacturing a liquid crystal display device, comprising a step of controlling the initial alignment of liquid crystal by applying the above voltage between a second electrode and an electrode facing the second electrode. 8. A voltage higher than the voltage applied between the electrode having the opening and the electrode facing the electrode is applied between the second electrode and the electrode facing the electrode, and the voltage is applied to the substrate. The method for manufacturing a liquid crystal display device according to claim 7, further comprising a step of applying pressure. 9. The method for manufacturing a liquid crystal display device according to claim 2, comprising: two substrates each having an electrode; and a liquid crystal insulated from the electrode on at least one of the substrates. Injecting liquid crystal into an empty panel provided with a second electrode for controlling the initial alignment of a voltage higher than the voltage applied between the electrode having the second electrode and the electrode facing the electrode. A step of applying between the second electrode and an electrode opposed to the second electrode to control the initial alignment of the liquid crystal. 10. Applying a voltage equal to or higher than the voltage applied between the electrode having the second electrode and the electrode facing the electrode between the second electrode and the electrode facing the electrode, The method for manufacturing a liquid crystal display device according to claim 9, further comprising a step of applying pressure to the substrate. 11. The method according to claim 8, wherein the pressure applied to the substrate is generated by ultrasonic waves. 12. A step of heating the liquid crystal injected into the empty panel until the liquid crystal becomes an isotropic phase, and in a state where a voltage is applied between the second electrode and an electrode opposing the electrode, the liquid crystal isotropically. 12. A step of cooling from a temperature not lower than the phase-liquid crystal phase transition temperature to a temperature not higher than the isotropic phase-liquid crystal phase transition temperature.
The method for manufacturing a liquid crystal display device according to any one of the above. 13. The liquid crystal according to claim 7, wherein the liquid crystal contains a polymer compound.
13. The method for manufacturing a liquid crystal display device according to any one of items 12. 14. The liquid crystal according to claim 7, wherein the liquid crystal contains a monomer or an oligomer, and after the liquid crystal is injected into the empty panel, the step of polymerizing the monomer or the oligomer in the liquid crystal is performed. A method for manufacturing a liquid crystal display device. 15. At least one substrate of an empty panel includes:
The method of manufacturing a liquid crystal display device according to claim 7, further comprising a step of performing a process of dividing a liquid crystal orientation direction. 16. The method for manufacturing a liquid crystal display device according to claim 15, wherein the process of dividing the alignment direction of the liquid crystal is performed by rubbing in different directions. 17. The method for manufacturing a liquid crystal display device according to claim 15, wherein the process of dividing the alignment direction of the liquid crystal is performed by light irradiation. 18. The method for driving a liquid crystal display device according to claim 1, wherein a voltage higher than a voltage applied between an electrode having an opening and an electrode facing the electrode is applied to the second electrode. A method for driving a liquid crystal display device, wherein a voltage is applied between an electrode facing the electrode and the electrode. 19. The method for driving a liquid crystal display device according to claim 2, wherein a voltage equal to or higher than a voltage applied between an electrode having a second electrode and an electrode facing the second electrode is applied to the second electrode. A method for driving a liquid crystal display device, wherein a voltage is applied between an electrode and an electrode facing the electrode.