JP2765555B2 - Liquid crystal display device, its manufacturing method and its driving method - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention
Liquid crystal display device, manufacturing method thereof and driving method thereof
With excellent visual characteristics and high cost
It is used as an untrusted liquid crystal display device. 2. Description of the Related Art A conventional liquid crystal display device uses a liquid crystal when a voltage is applied.
Problem of narrow viewing angle due to the behavior unique to crystalline molecules
have. The reason why the viewing angle of liquid crystal display devices is narrow
Thin film transistor
tor; TFT) driven liquid crystal display devices
Twisted nematic
c; TN) mode will be described as an example. FIG.
FIG. 26 is a sectional view of the liquid crystal display device when no pressure is applied, and FIG.
FIG. 3 is a cross-sectional view of the liquid crystal display device when a pressure is applied. [0003] Liquid crystal molecules are considered to be rod-like molecules.
In the N mode, as shown in FIG.
Between the glass substrates. That is, liquid crystal molecules
11 is almost a glass substrate for both the upper substrate 33 and the lower substrate 23.
They are oriented parallel. (However, the glass substrate interface is small.
It is oriented with a great pretilt angle 13. )actually
Are the azimuthal directions in the upper substrate plane and those in the lower substrate plane
Are arranged so that the orientation directions are substantially 90 °.
25 and in FIG. 26, this 90 °
No twist of liquid crystal molecules is shown. No voltage applied
There is no significant visual dependency in the state. When a voltage is applied to this TN array, FIG.
As shown in the figure, the liquid crystal molecules are aligned so that they are parallel to the electric field.
Change. At this time, the liquid crystal molecules rise from the pretilt angle direction.
Try to go up. The birefringence of liquid crystal molecules is determined by the long axis of the liquid crystal molecules.
And the angle between the rays. The central part of the cell in FIG.
Paying attention to the liquid crystal molecules of the
At a large angle to the molecular long axis, ray 41 is at a small angle
Make a degree. Therefore, the visual change to the left in FIG.
It exhibits different optical properties for visual changes in direction. Normal
In the liquid crystal display device of FIG. 26, the horizontal direction in FIG.
Is set to For this reason, visual changes in the upward direction
In contrast, the image becomes whitish and the contrast decreases
Recognized as "white floating" and responds to visual changes in the downward direction
The image becomes darker and the negative / positive is reversed.
Will be recognized as A technique for solving this problem is disclosed in Japanese Unexamined Patent Publication No.
It is disclosed in JP-A-3-106624 (FIG. 27).
In this prior art, one pixel of a liquid crystal display device is divided into a plurality of pixels.
Divided into regions (region I and region II), and
The direction of rubbing is changing. Rubbed alignment film table
Liquid crystal molecules on the surface cause pretilt, but are adjacent
Since the direction differs in the region, the liquid crystal molecules
The rising direction is reversed. As a result, visual dependence is adjacent
And the device is less dependent on vision.
You. That is, one pixel corresponds to the area where the liquid crystal molecules rise from the left.
Area and the area rising from the right.
The angle between the liquid crystal molecules and the light beam in one area is
And the angle formed by the liquid crystal molecules in the other region is small.
It will be cheap. This allows the entire pixel to respond to the tilt of the ray.
The optical characteristics are symmetrical, and the image
Rolling and whitening are suppressed. Further, the rubbing positions of the upper and lower substrates are shifted.
The technology for dividing one pixel into four areas is
It is disclosed in Japanese Unexamined Patent Publication No. Hei 5-173135 (see FIG. 2).
8). Another technique for solving the above problem is disclosed in
Japanese Patent Application Laid-Open No. Hei 6-194655 (FIG. 2)
9). In this prior art, the substrate surface is rubbed.
Liquid crystal molecules in the liquid crystal are 90 ° between the substrates.
A chiral agent is added to twist. In isotropic phase
When the liquid crystal is injected and cooled to room temperature, the alignment vector of the liquid crystal
The device varies depending on the location, and a continuously changing element is obtained.
You. In this element, each alignment state when the light beam is tilted
Contributions are averaged in all directions
Liquid crystal display device with little visual dependence
You. Another technique for improving visual characteristics is disclosed in
It is disclosed in Japanese Unexamined Patent Publication No. Hei 7-92466 (FIG. 30).
In this technology, a liquid crystal material containing a chiral material is
By using an alignment film with a tilt angle of 0 °,
JP-A-63-1066 without rubbing several times
A liquid crystal display device having a small visual dependency similar to that of JP-A-24
Have been obtained. SUMMARY OF THE INVENTION
Conventional liquid crystal display devices have the following problems.
You. First, JP-A-63-106624
(FIG. 27) and JP-A-5-173135 (FIG.
In the technique disclosed in 8), a different laser
Manufacture of normal TN type liquid crystal display device to perform bing
If a more resist process is required than the process
In addition, a plurality of rubbing steps are required. Also this
In order to accurately overlap the small areas of these upper and lower substrates,
Two substrates must be bonded with high precision. This
As a result, the liquid crystal display devices according to these disclosed technologies
Higher cost and production compared to conventional LCDs
Is reduced. On the other hand, JP-A-6-194655 (see FIG.
In the prior art described in 29), the alignment film is subjected to a rubbing process.
The alignment of liquid crystal molecules by the alignment film
Low power, injects liquid crystal between substrates in liquid crystal phase
And the flow pattern at the time of injection remains, and a good orientation state cannot be obtained.
No. Therefore, in this conventional technique, the entire substrate is heated,
Liquid crystal must be injected in isotropic state
Problem. Also, Japanese Patent Application Laid-Open No. 63-106624
(FIG. 27), JP-A-6-194655 (FIG. 29)
And JP-A-7-92466 (FIG. 30).
One of the common issues in advanced technologies is that
The problem that the light leakage reduces the contrast
There is. In other words, liquid crystal display devices using these technologies
In this case, the orientation direction of the liquid crystal
Crystal twisting direction) and the rise of liquid crystal molecules
Direction (hereinafter referred to as "the rising direction of liquid crystal")
The areas coexist in a state where they touch each other with a “line”.
Means that the boundary is seen as a `` line '' when viewed from the vertical direction of the board.
That is almost perpendicular to the substrate when viewed three-dimensionally.
In contact with each other as a “face”). I'll consider it later
As shown in FIG. 10, the liquid crystal molecules at the boundary between the two regions are
Even when voltage is applied, the arrangement state when no voltage is applied is maintained
It has been done. Therefore, black display is obtained by applying voltage.
(Normally white mode)
Light leaks from the field and the transmittance during black display is sufficiently small.
Obtain a liquid crystal display with high contrast
Can not do. A method for solving this reduction in contrast and
Then, it is conceivable to provide a light shielding mask at the boundary between the two regions.
However, in this method, the aperture of each pixel is
Rate decreases, and as a result, the brightness of the screen of the liquid crystal display device decreases.
The problem of lowering occurs. Further, Japanese Patent Laid-Open No. 7-92466 (FIG. 3)
In the technique disclosed in (0), non-uniformity occurs when a voltage is applied.
The electric field is generated mainly at the edge of the electrode.
There is no non-uniformity of the electric field at the center. For this reason, the electrodes
The rising direction of the liquid crystal at the center is the rising direction at the electrode end
In some cases, the directions do not match. This is especially true for voltage application.
Immediately after. Furthermore, such a rise occurs
In this case, two regions with different rising directions of the liquid crystal pass through.
The visual characteristics in the oblique direction will change over time
Is provided to cover the boundary as well as changes over time
There is a problem that the light shielding mask does not function effectively. The detailed situation of the movement of the boundary area
Are described in Japanese Patent Application No. 7-98336 (FIG. 3).
1). FIG. 31 uses an electrode having an opening 35 in a diagonal direction.
Shows the state of the used liquid crystal display device after voltage application.
is there. In the state H and the state L, the twist direction of the liquid crystal is the same,
2 shows two regions having different rising directions. Immediately after electric field application
After a lapse of a long time, the two regions following the opening 35
Divided, but different from opening immediately after voltage application
A boundary is generated at the position, and two types of areas are located at unintended positions
Occurs. Accordingly, the present invention solves the above-mentioned problems of the prior art.
LCD display with excellent visual characteristics and contrast
To provide an apparatus, a manufacturing method thereof, and a driving method
And [0017] The present invention solves the above-mentioned problems.
1) Regarding small area
Liquid crystal having different rising directions without rubbing
Area, as well as differences in the twisting and rising directions of the liquid crystal.
New technology to generate the following four regions in the liquid crystal layer, 2) liquid
Between two regions with different crystal twisting directions and rise of liquid crystal
The boundary between two regions with different directions shows optically different behavior
(There is no light leakage between two areas with different twist directions.
3) Different twisting directions of liquid crystal
The boundary between the two regions is defined as the boundary between the two regions having different rising directions of the liquid crystal.
New technology to be generated preferentially compared to the world, 4)
Such four micro regions coexist stably and are immobilized
Was made by discovering new technologies
is there. Specifically, the liquid crystal display device according to the present invention
Means that a liquid crystal layer made of nematic liquid crystal is sandwiched between two substrates.
In the held liquid crystal display device, a liquid crystal component is contained in the liquid crystal layer.
Two kinds of irregular micro-areas with different child rising directions coexist
It is characterized by doing. Further, another liquid crystal display device of the present invention has two sheets.
Liquid crystal layer composed of twisted nematic liquid crystal is sandwiched between substrates
Liquid crystal display device, wherein a liquid crystal screw is provided in the liquid crystal layer.
Micro regions with different deflection directions and different rising directions of liquid crystal molecules.
Is characterized by the coexistence of microscopic regions
Small areas with the same kinking direction but different rising directions of liquid crystal molecules
Are connected by a line on an imaginary plane crossing the liquid crystal layer.
Not characterized. Another liquid crystal display device of the present invention has two
Liquid crystal layer composed of nematic liquid crystal was sandwiched between substrates
In a liquid crystal display device, the twist direction and vertical
Four small areas with different upward directions coexist in one pixel
It is characterized by the following. Further, other liquid crystal display devices of the present invention
Liquid crystal display device that stabilizes the micro area of
Small amount of polymer in the liquid crystal layer to obtain
And features. The present invention also provides such a liquid crystal display device.
As a manufacturing method, liquid crystal is injected between two substrates, and
Temperature above the liquid crystal phase-isotropic phase transition temperature
To cool the liquid crystal layer from the temperature to below the phase transition temperature
And so on. Further, the present invention can be manufactured by such a method.
As a technology for stably existing the structure, a small amount of liquid crystal layer
Polymer-containing structure and liquid crystal layer
Sesame (hereinafter referred to as “monomer etc.”)
At a temperature higher than the liquid crystal phase-isotropic phase transition temperature of the liquid crystal.
Provided is a method for manufacturing a liquid crystal display device using a polymer. Further, the present invention relates to such a liquid crystal display device.
Drive method when a low level voltage is applied.
A driving method for applying a voltage equal to or higher than a threshold voltage is provided. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The configuration and operation of the present invention will be described below.
This will be described with reference to FIG. FIG. 1 shows an intermediate voltage of the liquid crystal display device of the present invention.
FIG. 4 is an enlarged perspective view of a liquid crystal layer for one pixel when voltage is applied.
You. In FIG. 1, as in FIG.
The 0 ° twist is omitted. The liquid crystal display device according to the present invention has two
Liquid crystal layer composed of twisted nematic liquid crystal is sandwiched between substrates
Liquid crystal display device, the liquid crystal molecules 11
Are two kinds of irregular minute areas A and B having different rising directions.
It is characterized by coexistence. It should be noted that the present invention is used to specify the configuration of the present invention.
The expression “irregular minute area” refers to resist
Use to intentionally divide one pixel into two or more small areas
Exclude “regular” micro-regions created by conventional techniques
It is a spontaneous and naturally occurring
Micro-regions with regularly generated irregularities
"Area". The liquid crystal layer has such a structure for each pixel.
By having, the visual dependence of the two regions offsets,
Even in halftones, there is little visual dependency in the vertical direction
A liquid crystal display device having a wide viewing angle can be obtained. Liquid in halftone
FIG. 2 shows a sectional view of the crystal layer. In FIG. 2, the light is oblique
The regions A and B have the opposite relationship with respect to the lines 41 and 42,
Visually dependent surnames offset. FIG. 3 shows another example of the liquid crystal display device of the present invention.
Will be described. FIG. 3 shows an intermediate voltage of the liquid crystal display device of the present invention.
Enlarge one pixel at the time of application and view from the vertical direction of the substrate.
FIG. 5 shows the cell thickness of each micro area (A, B, C, D)
The rising state of the liquid crystal molecules in the center is shown. Also, in FIG.
Arrows indicate the twist direction of the liquid crystal molecules. In this invention
In FIG. 1, regions A having different rising directions of the liquid crystal molecules shown in FIG.
In addition to B, the twist direction is different from A and B,
Sum of regions C and D where the rising directions of liquid crystal molecules are different from each other
Four types of minute regions coexist. These four types of micro regions A, B, C, and D
The rising direction of the liquid crystal molecules 11 is as shown in FIG.
They differ by 90 °. As described with reference to FIG.
Field of view in which crystal molecules rise (downward direction of normal TN device)
Although the angle is narrow, in the liquid crystal display device of the present invention, the liquid crystal
Four types of micro regions with different rising and twisting directions coexist
As a result, the rising direction of the resultant liquid crystal molecules is shifted by 90 °.
It consists of four types of micro regions, so in all directions
A liquid crystal display device having a wide viewing angle without gradation inversion can be obtained. Incidentally, four kinds of fine patterns are considered from the viewpoint of improving the visual characteristics.
It is not desirable that the size of the small area is too large.
Four kinds of micro areas coexist in each pixel
Is desirable. However, displaying one color with multiple pixels
In some cases, there are four types of micro regions in one pixel
It is not a mandatory requirement to do so. FIG. 1 is composed of two types of minute regions, and FIG.
It consists of three kinds of micro-areas,
A liquid crystal display device in which regions coexist can also be manufactured. concrete
The method is to add a very small amount of chiral agent,
It depends on cooling. Another Liquid Crystal Having Four Kinds of Small Areas of the Invention
An example of the display device will be described with reference to FIGS. Figure 4 is a book
Liquid crystal table at intermediate voltage application of the liquid crystal optical element of the invention
Enlarged view of one pixel of the display device viewed from the vertical direction of the substrate
It is. FIG. 4 shows the rising of liquid crystal molecules in the center of the liquid crystal layer.
And the arrow indicates the twist direction of the liquid crystal.
It is. FIG. 5 is a sectional view of the present invention taken along the line cc 'in FIG.
FIG. 2 is a cross-sectional view of a liquid crystal display device. In the liquid crystal display device of the present invention, four
Small area exists in one pixel and its shape
More controlled. In the liquid crystal display device of the present invention shown in FIG.
Four different liquid crystal twist directions and rising directions
Not only micro areas A, B, C, and D
The two regions where the rising directions of the liquid crystal are opposite in the element are symmetric.
At the same location and their sizes are almost equal. Follow
The "white float" and "black crush" exactly offset each other,
Excellent visual characteristics are obtained in all directions. In the liquid crystal display device of the present invention, "four fine
Small area means that the liquid crystal twist direction and rising direction are different
It means that it consists of almost four minute areas, strictly "4
It does not need to consist of only one area. for example
For example, if any area is divided into two
Or one pixel divided into two or three, and each of them is divided into four
May be constituted by the minute regions of the above. Also,
As shown in FIG. 4, the four micro regions are exactly divided into four equal parts.
It is not necessary to change the ratio intentionally.
You may. On the other hand, in the liquid crystal display device of the present invention,
The control of the micro-areas is a naturally occurring factor, as described later.
The boundary is not limited to a straight line, but is a curve.
You may. In the liquid crystal display device according to the present invention,
The important point is that the liquid crystal
Regions with the same kinking direction but different rising directions of liquid crystal molecules
(A and B, C and D in FIG. 3 or FIG. 4) are on the virtual plane.
And not touching each other with a line. As a result, the liquid crystal display device of the present invention
-Only the visual characteristics are excellent in the Mari White mode.
Nos. JP-A-63-106624, JP-A-6-106624
Higher cost than the prior art described in Japanese Patent No. 94655.
You can get trust. The liquid crystal display device of the present invention has, for example, the following:
Is realized by using such alignment means and liquid crystal materials.
It is. First, the alignment means of the present invention includes a liquid crystal component.
Orientation method in which two rising directions of a child are generated with almost the same probability
It is necessary to use steps. Rise direction is one direction
Only two or four types of microregions do not occur.
You. Therefore, a rubbing alignment film is used as the alignment means.
In this case, two rising directions are generated with almost the same probability.
Use a membrane. By such a single rubbing, two types of standing are obtained.
For example, the following two alignment films can coexist in the upward direction.
Of the alignment film. One is a pre-generated rubbing.
The alignment film has a small tilt angle. Conventionally known alignment films have rabbi
The rising direction of the liquid crystal molecules was determined by the orientation of the ring.
This is because the rubbing operation flattens the alignment film in the rubbing direction.
This is caused by producing a pretilt angle in the row. others
In conventional alignment films, liquid crystal molecules are
Unable to generate two types of areas with different rising directions
Function, or even if two regions are created
Was unstable and impractical. The present invention solves this problem.
Rubbing, two types of rises by one rubbing
By using an alignment film whose direction can coexist stably,
In the same simple process as the conventional TN type liquid crystal display device fabrication
Obtain a liquid crystal display device with a wider viewing angle and higher contrast
be able to. That is, as in the conventional process, one lath
The two types of areas where the liquid crystal molecules rise in different directions
Region or the region where the twist direction of the liquid crystal is different and the liquid crystal component
Wide viewing angle generated by four types of regions in which the child rises in different directions
Of the present invention can be obtained. Therefore,
Since rubbing is not required for each minute area,
JP-A-3-106624, JP-A-5-173135
Rubbing steps like the technology disclosed in the report
Also, no resist process is required. Also, each substrate
Is rubbed once, so it is aligned with liquid crystal molecules.
The force is strong and the flow orientation during injection does not matter. Follow
Can be implanted at room temperature, and the substrate is heated during the implantation.
You don't have to. An alignment film having such a low pretilt angle
As specific polyimide, polystyrene etc.
be able to. Use an alignment film with a small pretilt angle
As a result, when the rising directions of the liquid crystal molecules are different,
Energy difference is small and the liquid crystal molecules
The present invention in which the state stably exists while rising from
Can be obtained. Specifically, this
Such a low pretilt alignment film has a pretilt angle of
An alignment film having an angle of 0.5 ° or less can be given. Ma
In addition, a certain polymer (for example, polystyrene)
When used as a
And the liquid crystal molecules are aligned perpendicular to the rubbing direction.
Turn around. In such an alignment film, the rubbing direction and
The direction of retilt generation is vertical, and the pretilt angle is almost
An alignment state close to 0 is obtained. The pretilt angle is determined by the crystal rotation.
It can be measured by a measurement method or the like. On the other hand, two types of micro regions having different rising directions
In the liquid crystal device of the present invention having
Without using a small alignment film, adding a chiral agent
The rising direction of the seed can be generated with almost equal probability.
Wear. The arrangement used for the liquid crystal display device of the present invention is also described.
As a means for directing, liquid crystal molecules on the substrate surface are
For microscopic grooves such as those oriented in one direction or groups
More oriented ones are available, but in this case
Also, it is necessary that rising in two directions be generated with almost equal probability.
It is necessary. This is because the alignment surface and micro grooves due to polarized light
Corresponding to what should not be inclined to
It can be easily created by the above method. Orientation treatment by linearly polarized light
For example, Japan Journal
Bu Applied Physics (Jap. J. App
l. Phys. ), Vol. 31 (1992) PP. 2
155-2164 or Nature
e), Vol. 351 (1991) PP. 49-50
There is a method described. In addition, these alignment films are used alone.
In addition to these, these alignment films are coated and aligned with linearly polarized light.
After processing, for example, Liquid Crystals (Li
liquids), Vol. 18, (199
5) Photopolymerization as described in PP319-326
Apply a liquid crystalline monomer having a group
After aligning the liquid crystalline monomer, photopolymerize and align the film
Can be used to obtain a more stable alignment state.
It is. The rising directions of the two types of liquid crystals coexist stably.
Another approach is to use the two irregular regions shown in FIG.
Liquid crystal display device has liquid crystal layer
To include a chiral material with a twisting direction
It depends. The splay arrangement is the orientation state shown in FIG.
(Fig. 6 omits 90 ° twist for easy viewing)
25), which is opposite to the normal tilt arrangement shown in FIG.
Is what you do. When an alignment film having a small pretilt is used
The difference between the spray arrangement and the normal tilt arrangement is small.
However, they are not completely the same,
There is a difference in the stability of the two different regions. Sand
That is, by using a splay arrangement, two rising areas are provided.
Are almost equal, and stable
A small area can be obtained. The relationship between the rubbing direction and the arrangement of the liquid crystal molecules is described.
FIG. 7 shows the relationship. 24 and 34 are above
The rubbing direction of the side substrate and the lower substrate is shown. Figure 7
C is a spray arrangement and D is a normal tilt arrangement.
You. The liquid crystal molecules are aligned perpendicular to the rubbing direction.
When an alignment film is used, in principle, the pretilt angle
It does not occur in a specific direction. But actually Rabin
How to rise in both twisting directions due to delicate conditions during
Two regions with different directions may not be equally stable
is there. For this reason, the direction in which the two regions are stabilized is experimentally determined.
Determined, a chiral agent with the appropriate rotation direction is added
You. Next, from the point of view of the liquid crystal material, its twist characteristics
However, it is important in the liquid crystal display device of the present invention. In the liquid crystal display device of the present invention, the liquid crystal molecules
Direction can be controlled freely by adding chiral agent
be able to. As described above, the addition of chiral material
When controlling to the play arrangement, or with a low pretilt angle
When the torsion direction is controlled in one direction by using a membrane
Means that only two regions with different rising directions of liquid crystal molecules
The liquid crystal display device of the present invention as shown in FIG. 1 is obtained. On the other hand, is the chiral material not added at all?
If the amount of addition is small,
Of the liquid crystal molecules with different rising directions
As shown in FIG. 3 or FIG. 4 in which a total of four types of micro regions coexist.
A liquid crystal display device is obtained. That is, two torsion directions
Are generated with almost equal probability.
Liquid crystal display device of the present invention in which
You. In the liquid crystal display device of the present invention, the liquid crystal layer
No drive voltage increase due to the absence of lumps
There are advantages too. Further, the amount of chiral material is controlled to a very small amount.
There are four types of regions by controlling
Liquid crystal display devices having different ratios can be obtained. This
In this case, as shown in FIG.
The size can be intentionally made uneven. this is,
The viewing angle characteristic of the liquid crystal display device is four-fold symmetric as shown in FIG.
Is not always the best,
Liquid crystal display device with wider view, liquid with wider view in left and right direction
Because it is sometimes required to be a crystal display device.
You. Therefore, in the liquid crystal display device of the present invention, a small amount of
Liquid with a wider viewing angle in the vertical direction by adding a chiral agent
LCD devices and LCD devices with a wider viewing angle depending on the horizontal direction
It is possible to freely make which one. The liquid crystal having the intermediate viewing angle characteristic
Also in the display device, the twist direction of the liquid crystal is the same,
Structures in which regions with different rising directions of molecules do not directly contact
Can get a high contrast
You. As described above, the rising directions of the four liquid crystal molecules
Liquid that does not have the property of twisting in one direction and the alignment means that generates
By using crystalline materials, the twisting direction of liquid crystal molecules
Different regions and regions with different rising directions of liquid crystal molecules coexist
Liquid crystal display device is obtained. However, only under these conditions
“4 small areas” as shown in FIG. 4 and FIG.
Existing liquid crystal display devices cannot be obtained,
It is a liquid crystal display device that generates the data in the system. Eliminating the randomness of the four types of regions,
By controlling the shape of the four micro regions,
A liquid crystal display device having excellent viewing angle characteristics can be obtained. This
The use of a non-uniform electric field, etc.
You. For example, as shown in FIG.
32 larger than the electrode 22 of the lower substrate 23
The method of forming the electrodes on the substrate in different shapes, as shown in FIG.
An opening is formed in the electrode 32 on at least one of the substrates.
35 can be provided. Such an opening
The parts include shapes such as "+", "x", "/", etc.
A straight line, a circle, a polygon, etc. can be used as appropriate. Ma
Further, in a normal substrate with a TFT, the common electrode side and T
Generally, the electrodes on the FT substrate side have different shapes
The non-uniform electric field due to this difference in shape is used as it is.
By using, the liquid crystal display device of the present invention can be obtained.
it can. In this case, what voltage is applied during cooling
Is particularly important. The voltage is applied to generate four minute regions.
The constant voltage or the response of the liquid crystal molecules
Although it is possible to use an AC wave voltage with a high frequency that cannot be
Low frequency triangular wave, sine
It is better to use a wave, square wave, etc.
Good area where areas with different rising directions do not touch
A liquid crystal display device having characteristics is easily obtained. The liquid crystal of the present invention having four types of regions
The important point in the display device is the four small areas that coexist
Liquid crystal twist direction is the same and liquid crystal rise direction is different
Regions (A and B, C and D in FIG. 3 or FIG. 4) are virtual
That is, they do not touch each other on a plane. Here, "on a virtual plane" is defined.
This is for the following reasons. In Figure 4, how to twist the liquid crystal
Two regions having different directions, for example, B and C are connected by a "line".
(This boundary does not cause light leakage). Only
And that the liquid crystal layer has a finite thickness and is three-dimensional.
Strictly speaking, B and C must be in contact
And Similarly, if the twist direction of the liquid crystal is the same and the liquid crystal
Regions having different upward directions, for example, A and B are shown in FIG.
Are tangent at "points", but when considered three-dimensionally, "lines"
In contact. “On the virtual plane” is such a misunderstanding.
Is specified so as not to occur. For example, virtual
As a plane, the center of the upper and lower substrates 23 and 33 is parallel to the substrate
Can be considered, and the boundary on this plane is
For example, it is the same as FIG. Therefore, the content of the present invention is defined.
The “virtual plane” does not include a plane perpendicular to the substrate.
However, there are cases where the LCD device is viewed from an oblique direction.
Is strictly parallel to the substrate,
It is not necessary to use a virtual plane that is inclined with respect to the substrate surface.
No. The twisting direction of the liquid crystal in the four minute regions is
Areas that are the same but have different rising directions of the liquid crystal
By having a structure that does not touch with a line in
The liquid crystal display of the present invention has the following advantages. First, the liquid crystal display device of the present invention has such a structure.
The structure not only provides excellent viewing angle characteristics, but also
-106624, JP-A-7-92466
Normally white mode compared to the disclosed liquid crystal display
The use of high-contrast
A trust liquid crystal display device can be obtained. In particular, the four types of regions shown in FIG.
Many boundaries exist due to the presence of
In a difficult liquid crystal display device, light leaks from the boundary.
The effect which does not change is remarkable. The liquid crystal display of the present invention having such effects
Use Fig. 10 and Fig. 11 to explain the reason why the device has high contrast.
And will be described in more detail. FIG. 10 shows a conventional liquid crystal display device.
Liquid crystal twisting directions are the same and the rising directions are different.
FIG. 11 shows the boundary of the region where the twist direction of the liquid crystal is different.
Respectively indicate the boundaries of the regions. (A)
(B) shows a voltage applied state, and FIG.
You. The liquid crystal rises when the twist direction of the liquid crystal shown in FIG. 10 is the same.
The liquid crystal molecules at the boundary between the two regions with different directions
Even when voltage is applied, it remains horizontal with respect to the substrate,
Hold the initial 90 ° twisted state when no pressure is applied
Continue (FIG. 10B). Therefore, normally white
In the mode, the voltage application state that should be displayed as “black”
Also, the boundary remains "white" when no voltage is applied
And the light leakage at this boundary causes the transmittance of "black" display
And the contrast of the LCD is low.
Down. On the other hand, two regions with different twist directions of liquid crystal
At the boundary of the region (FIG. 11), the liquid crystal molecules at the boundary are
The orientation is changed to the direction of the electric field with the application of voltage,
Under a sufficient voltage application like the liquid crystal molecules in the TN cell,
It is perpendicular to the substrate (FIG. 11A). Therefore, how to twist
Even when the voltage is applied at the boundary between two regions with different directions
Display is “black”, and the liquid crystal display device with high contrast
Is obtained. The liquid crystal has the same twisting direction and different rising directions.
Are not touched by a line on the virtual plane
Other advantages of the liquid crystal display device of the present invention having a structure are as follows.
Is a point. [0073] Japanese Patent Application Laid-Open No. Hei 5-173135 discloses
Rubbing each micro area intentionally
In this case, the rising direction of the liquid crystal is
Because it is determined by the regulating force, the liquid
Regions where the rising directions of the crystals are opposite are unlikely to occur. Only
And a liquid crystal display disclosed in JP-A-4-92466.
When a voltage is not applied like a device, it forms a uniform area,
The rise of the liquid crystal by the action of the non-uniform electric field only when voltage is applied
In a liquid crystal display device in which regions in different directions occur,
The rising direction of the liquid crystal at the center of a pixel with a weak non-uniform electric field
A paired region is likely to occur. In contrast, the liquid of the present invention
In a liquid crystal display device, the liquid crystal
Since there are regions with different twist directions, when no voltage is applied
Each area in becomes a small area,
Regions with different twist directions of the liquid crystal alternate
(This is because the liquid crystal has the same twisting direction and different rising directions.
Areas are not connected by a line).
Adjacent even if the rising direction of the area is reversed
There is no light leakage problem at the boundary with the
Optical characteristics are obtained. In the liquid crystal display device of the present invention, the screw of the liquid crystal
The two directions are the same, and the rising directions are different.
The reason why the structure not in contact with the line appears is explained as follows.
Will be revealed. The rising direction of liquid crystal molecules or twist of liquid crystal
At the boundary between areas with different directions,
The liquid crystal has a distorted orientation compared to the
Due to high energy. But how to get up
The boundary between the regions with different directions and the boundary between the regions with different torsional directions
The distortion of the liquid crystal in the boundary area is different, and
The energy is also different. At the boundary of the areas with different rising directions
The strain energy at the boundary between regions with different torsional directions
If the energy is higher than the strain energy,
The boundary of the area with a different twist direction than the boundary of the area
The part is expected to generate preferentially. The present invention has been developed based on such knowledge.
Two types of crystals with the same twisting direction and different rising directions
To disclose a liquid crystal display device in which the regions do not touch with a line
Both also disclose the manufacturing method. Less than,
A method for manufacturing the liquid crystal display device of the present invention will be described. A liquid crystal display provided with the above-described alignment means and liquid crystal material
Display device, the twisting direction and the rising direction of the liquid crystal
The four different types of areas are made into a micro area with almost the same ratio.
To obtain a liquid crystal layer, first heat the liquid crystal layer to an isotropic phase and then
Cooling method to below the phase transition temperature between crystal phase and isotropic phase is desirable
New In this process, many liquid crystal droplets are generated from the isotropic phase.
Generated, four types of liquid crystal with different twisting and rising directions
A region is generated. It is important that the liquid crystal display of the present invention
This cooling operation, as specified in the
Is performed under voltage application. This allows the liquid crystal screw
The two directions are the same, and the rising directions are different.
The liquid crystal display of the present invention which is not touched by a line on a virtual plane
A device can be obtained. Under such conditions, the liquid crystal display device of the present invention
Is obtained as follows. No voltage mark
In the added state, the twist direction is the same and the rising direction is different.
The areas are substantially the same (FIG. 10 (a)). Therefore,
No strain energy is generated at the boundary of the region. one
On the other hand, the boundary between the areas with different torsional directions
Exists and is in a state of high strain energy.
As a result, when the cooling operation is performed with no voltage applied, the twist direction
Two regions with the same and different rising directions are in contact with a line
High-contrast liquid crystal display with easy-to-generate structure
I can't get it. On the other hand, under voltage application,
10 (b), as expected in FIG. 11 (b),
At the boundary of the area where the twist direction is the same and the rising direction is different
In this case, the liquid crystal at the boundary remains in a state where no voltage is applied.
The strain energy increases rapidly with the applied voltage
Region where the twist direction is different
The liquid crystal molecules in the same direction as the surrounding liquid crystal molecules
Strain energy does not increase much to change direction
No. Therefore, when the cooling operation is performed under voltage application,
Areas where the torsion direction is the same and the rising direction is different touch with a line
LCD with high viewing angle and high contrast
Is obtained. Including the manufacturing process of the liquid crystal display device of the present invention
By thinking, the twisting direction of the liquid crystal is the same and the rising direction
Areas with different directions do not touch each other on the virtual plane
The advantages of the structure of the present invention can be further clarified.
You. In the method of intentionally rubbing each minute area
The rising direction of the liquid crystal is determined by the rubbing direction.
Therefore, the regulating power is generated from the surface,
Thus, a rising region as controlled can be obtained. On the contrary,
Each minute area in the liquid crystal display device of the present invention starts from an isotropic phase.
Is generated from liquid crystal droplets generated when cooling
In an area where a non-uniform electric field is not applied,
State control is likely to be insufficient. But in this case smell
Even in the liquid crystal display element of the present invention, the liquid crystal twist directions are the same.
In this structure, areas with different rising directions are not connected by lines.
Because there is no light leakage from the boundary, high contrast
Can be maintained. The liquid crystal display device of the present invention described above is
Basically, it has excellent characteristics such as wide viewing angle and high contrast.
Yes, but it is not without its challenges. One is that if the microregion is not sufficiently stable,
In particular, in the ON-OFF repetition of the voltage,
The border moves and one of the small areas disappears
There are cases. Another issue is the liquid crystal molecules immediately after voltage application.
Rising direction is stable after a sufficient time has passed
The direction may be different from the direction. As a result, the voltage
Immediately after application, the liquid crystal twist direction is the same and the rising direction
Are different from each other, and light leaks from the boundary.
And this boundary equilibrates at a slow speed on the order of seconds.
Because it moves toward the state, if the response speed becomes slow
In particular, when the characteristics in the oblique direction change with the movement of the boundary,
There is a case. Further, the minute area of the liquid crystal display device of the present invention is
When the liquid crystal layer is heated to the isotropic phase, it disappears.
Yes, if the liquid crystal layer is heated to the isotropic phase,
It is necessary to generate minute regions under non-uniform electric fields, etc.
Problem. To solve these problems, another invention and
And a liquid crystal display device in which a polymer is present in the liquid crystal layer.
And a method for producing the same. As such a liquid crystal display device, FIG.
As shown, a small amount of polymer 12 is
Those dispersed in the form of a work can be mentioned. This
The presence of the macromolecule stabilizes the four micro domains,
Even when the voltage is turned on and off repeatedly, the boundary moves.
Liquid crystal display device in which four small areas do not disappear
Is obtained. In this case, it is necessary to fix the four micro areas.
The effect is sufficient even if the amount of polymer is very small.
Is obtained. In addition, the presence of the polymer 12 causes the
After the rising direction of the liquid crystal molecules after a sufficient time
Is fixed at the same position as the stable rising direction of the
There is no light leakage and the response speed does not slow down.
No. In addition, when the amount of polymer is large, the liquid crystal layer
Liquid that recovers to its initial state when it is heated and then cooled
A crystal display device can also be obtained. Polymer present in a small amount in the liquid crystal layer of the present invention
Are different in the twist direction of liquid crystal and the rising direction of liquid crystal molecules.
Because it is intended to stabilize the area,
It is not particularly limited to a network shape or the like as long as it has a function.
Therefore, a polymer may be present on the substrate in the form of a protrusion,
Method of dispersing fine beads etc. on the alignment film to make it uneven
It may be. Also, fixation of a minute area on the surface of the alignment film.
Is a problem, so a very small amount of polymer is sufficient.
is there. On the other hand, if the amount of the polymer is too large,
The orientation of the liquid crystal molecules is disturbed by the
Or the scattering caused by the polymer causes the contrast to increase.
May cause a decrease. Therefore, the amount of polymer
Depends on the type of liquid crystal molecules and the interaction with the liquid crystal molecules.
Desirably, the content is 0.02 wt% or more and 4 wt% or less.
No. The liquid crystal display device of the present invention shown in FIGS.
In any case, the rising direction of the liquid crystal molecules
It can also be used, but it is optional, but the polymer is dispersed
The rising direction when the voltage is first applied.
To remember the small amount of coexisting macromolecules,
The liquid crystal molecules rise in the rising direction.
Do not move. In other words, a small amount of polymer dispersed in liquid crystal
Due to the coexistence, the position of the boundary of the micro area is fixed,
To reduce the response speed and contrast ratio of
And not. However, it is necessary to limit the rising direction of the liquid crystal molecules.
In order to stabilize the microscopic region,
I need. In the present invention, the polymer 12 dispersed in the liquid crystal layer is
A polymer dispersed in liquid crystal is introduced between the substrates.
It can be introduced between substrates in which monomer etc. are dissolved
After that, it can be converted into a polymer by reacting monomers etc.
Wear. However, ease of implantation and stabilization of initial orientation
It is desirable to react monomers etc. in the liquid crystal phase.
No. In this method, monomers and the like are applied under voltage application.
Reacts with each other to make the initial alignment of liquid crystal molecules
Drive voltage and response speed.
There are advantages too. Therefore, the present invention relates to the manufacture of such a liquid crystal display device.
A fabrication method is also provided. That is, the rise of liquid crystal molecules when voltage is applied
Combine to form irregular areas with different directions
A small amount of monomer or oligomer between the two substrates
Liquid crystal solution, followed by the monomer or oligo.
Provided is a method of manufacturing a liquid crystal display device that reacts a mask. Further, the monomer in the liquid crystal is irradiated by ultraviolet irradiation or the like.
-When reacting, etc., the state where the orientation of the liquid crystal is memorized
Forms a polymer. On the other hand, it includes minute regions having different twist directions.
In the case of a liquid crystal display device, the temperature at which the liquid crystal becomes isotropic is violet.
By irradiating the outside line, high
Make a molecule or create a small area in advance and
It is desired to use a method of irradiating ultraviolet rays etc. in a form that fixes the orientation state of
Good. In this case, the curing of the monomer is divided into two stages
Is also useful. That is, the first stage
After the reaction, a minute area is formed,
The reaction of the second stage proceeds in the
This is to fix the rising direction of the liquid crystal molecules immediately after the addition. In the production of a liquid crystal display device containing a monomer or the like,
However, under voltage application, the liquid crystal phase-isotropic phase transition temperature
The liquid crystal layer can be cooled from above to below the phase transition temperature.
Manufactures liquid crystal display devices with wide viewing angles and high contrast
It is useful for
In the method of making a polymer, under any conditions,
Is influenced by the characteristics of the liquid crystal display device. You
That is, a state in which a liquid crystal material at room temperature or the like forms a liquid crystal phase.
In case of reacting monomer etc., it was formed by reaction
The polymer remembers the orientation of the liquid crystal phase. So, like this
When the monomer is reacted under the conditions,
-Obtaining four minute regions evenly by the cooling process.
It is difficult. Then, as another invention, a small amount of liquid crystal layer is used.
Containing a monomer, reacting the monomer and the like to form a polymer
Liquid crystal phase of a liquid crystal,
React monomers etc. at temperatures above the phase transition temperature of the isotropic phase
A method of manufacturing a liquid crystal display device using a polymer as a polymer is disclosed. This
As a result, the orientation of the generated polymer is random,
Good 4 according to the cooling condition of the liquid crystal layer after the reaction of nomer etc.
Can be obtained. Therefore, under any condition,
The characteristics of the liquid crystal display device change depending on whether or not the above operation is performed. Right
The kinking direction is limited to only one direction, and the rising direction is different
In the case of a liquid crystal display device having two types of minute regions,
Cures monomer at room temperature due to stability of liquid crystal when pressure is not applied
The preferred method is Further, a small region having a different twist direction is included.
As a method of reacting a liquid crystal display device at room temperature,
Applying a voltage to make the liquid crystal molecules stand
There is a method of curing. If the monomer concentration is low,
The reaction force of the polymer is weak, so the voltage after the reaction
Except for, the liquid crystal molecules are oriented in a direction parallel to the substrate surface.
Also, by reacting monomers etc. under voltage application
Pretilt the initial alignment of liquid crystal molecules,
Another advantage is that the response speed can be improved. After reacting monomers and the like, four
Below the isotropic phase-liquid crystal phase transition temperature
It is not desirable to react monomers etc. at the temperature of
Conversely, fix the four micro regions that have already been created
From the viewpoint that the monomer reacts at room temperature,
Can be fixed. Liquid crystal display device of the present invention
The four small areas usually heat the liquid crystal layer to the isotropic phase
Disappears. However, after four small areas are created
Then, the monomer in the liquid crystal layer reacts to form a polymer.
This structure is fixed or memorized, and the temperature above the phase transition
Even if it is heated by cooling to the liquid crystal phase again
A liquid crystal display device in which four minute areas recover can be used.
Wear. Therefore, a method for manufacturing another liquid crystal display device has been developed.
Liquid crystal display that reacts monomers etc. in the liquid crystal layer
In the manufacturing method of the device, the monomer etc.
Reacting the liquid crystal display device,
Disclose. In the present invention, the first-stage weak reaction
Polymer to help stabilize four micro domains
Then, four minute regions are generated by subsequent cooling,
This structure is fixed by a two-step reaction. Obedience
Therefore, in the present invention, the reaction of the first step is mainly performed at the phase transition temperature.
Below the temperature, the second stage reaction is at a temperature above the phase transition temperature.
Do it in degrees. The monomers and oligomers used in the present invention
Photo-curable monomer, thermo-curable monomer, or
Any of these oligomers can be used,
If it contains these, it may contain other components.
No. The "photocurable monomer or oligo" used in the present invention
"Ma" means not only those that respond to visible light but also purple
Including UV-curable monomers that react with external light,
The latter is particularly desirable from the viewpoint of ease. The polymer used in the present invention has a liquid crystal component.
May have a structure similar to that of the
Is not used for the purpose of aligning
It may be flexible with a kylene chain
No. Further, it may be monofunctional or bifunctional.
, Even monomers having trifunctional or higher polyfunctionality, etc.
Good. Light- or UV-curable materials used in the present invention
Examples of the mer include, for example, 2-ethylhexyl acryle
Butylethyl acrylate, butoxyethyl acrylate
Relate, 2-cyanoethyl acrylate, benzyla
Acrylate, cyclohexyl acrylate, 2-hydro
Xypropyl acrylate, 2-ethoxyethyl acryl
Rate, NUN-diethylaminoethyl acrylate,
NUN-dimethylaminoethyl acrylate, dicyclo
Pentanyl acrylate, dicyclopentenyl acryle
Glycidyl acrylate, tetrahydrofurfurfurate
Acrylate, isobonyl acrylate, isodecyl
Acrylate, lauryl acrylate, morpholine acrylate
Relate, phenoxyethyl acrylate, phenoxy
Diethylene glycol acrylate, 2,2,2-tri
Fluoroethyl acrylate, 2,2,3,3,3-pe
N-fluoropropyl acrylate, 2,2,3,3-
Tetrafluoropropyl acrylate, 2,2,3
A simple substance such as 4,4,4-hexafluorobutyl acrylate
Functional acrylate compound, 2-ethylhexyl methacrylate
, Butylethyl methacrylate, butoxyethyl
Methacrylate, 2-cyanoethyl methacrylate,
Benzyl methacrylate, cyclohexyl methacrylate
G, 2-hydroxypropyl methacrylate, 2-eth
Xyethyl acrylate, NUN-diethylaminoethyl
Methacrylate, NUN-dimethylaminoethyl meth
Acrylate, dicyclopentanyl methacrylate, disilicide
Clopentenyl methacrylate, glycidyl methacrylate
, Tetrahydrofurfuryl methacrylate, isobo
Nyl methacrylate, isodecyl methacrylate, lau
Ril methacrylate, morpholine methacrylate,
Nonoxyethyl methacrylate, phenoxydiethylene glycol
Recall methacrylate, 2,2,2-trifluoroe
Tyl methacrylate, 2,2,3,3-tetrafluoro
Propyl methacrylate, 2,2,3,4,4,4-f
Monofunctional methacrylates such as xafluorobutyl methacrylate
Rate compound, 4,4'-biphenyl diacrylate,
Diethylstilbestrol diacrylate, 1,4-
Bisacryloyloxybenzene, 4,4'-bisact
Liloyloxydiphenyl ether, 4,4'-bisur
Acryloyloxydiphenylmethane, 3.9-bis
[1,1-dimethyl-2-acryloyloxyethyl]
-2,4,8,10-tetraspiro [5,5] undeca
, Α, α'-bis [4-acryloyloxyphenyl
Ru] -1,4-diisopropylbenzene, 1,4-bis
Acryloyloxytetrafluorobenzene, 4,4 '
-Bisacryloyloxyoctafluorobiphenyl,
Diethylene glycol diacrylate, 1,4-butane
Diol diacrylate, 1,3-butylene glycol
Diacrylate, dicyclopentanyl diacrylate,
Glycerol diacrylate, 1,6-hexanediol
Rudiacrylate, neopentyl glycol diacryle
Sheet, tetraethylene glycol diacrylate, tri
Methylol propane triacrylate, pentaerythri
Tall tetraacrylate, pentaerythritol tri
Acrylate, ditrimethylolpropane tetraacrylic
Rate, dipentaerythritol hexaacrylate,
Dipentaerythritol monohydroxypentaacryle
, 4,4'-diacryloyloxystilbene,
4,4'-diacryloyloxydimethylstilbene,
4,4'-diacryloyloxydiethylstilbene,
4,4'-diacryloyloxydipropylstilbe
, 4,4'-diacryloyloxydibutylstilbe
, 4,4'-diacryloyloxydipentylstil
Ben, 4,4'-diacryloyloxydihexylsty
Ruben, 4,4'-diacryloyloxydifluoros
Chilben, 2,2,3,3,4,4-hexafluorope
Tandiol, 1,5-diacrylate, 1,1,
2,2,3,3-hexafluoropropyl-1,3-di
Government officials such as acrylate and urethane acrylate oligomer
Acrylate compound, diethylene glycol dimethac
Acrylate, 1,4-butanediol dimethacrylate,
1,3-butylene glycol dimethacrylate, dicycl
Lopentanyl dimethacrylate glycerol dimethacrylate
Rate, 1,6-hexanediol dimethacrylate,
Neopentyl glycol dimethacrylate, tetraethyl
Len glycol dimethacrylate, trimethylol pro
Pantrimethacrylate, pentaerythritol tetra
Methacrylate, pentaerythritol trimethacrylate
, Ditrimethylolpropane tetramethacrylate
G, dipentaerythritol hexamethacrylate, di
Pentaerythritol monohydroxypentamethacrylate
2,2,3,3,4,4-hexafluoropenta
1,5-dimethacrylate, urethane methacrylate
Polyfunctional methacrylate compounds such as
Tylene, aminostyrene, vinyl acetate, etc.
It is not limited. The driving voltage of the device of the present invention is
It is also affected by the interface interaction between the material and the liquid crystal material.
It may be a polymer containing a nitrogen element. Such high
2,2,3,3,4,4-hexafluorope
Tandiol, 1,5-diacrylate, 1,1,
2,2,3,3-hexafluoropropyl-1,3-di
Acrylate, 2,2,2-trifluoroethylacryl
Rate, 2,2,3,3,3-pentafluoropropyl
Acrylate, 2,2,3,3-tetrafluoropropyl
Ruacrylate, 2,2,3,4,4,4-hexaful
Orobutyl acrylate, 2,2,2-trifluoroe
Tyl methacrylate, 2,2,3,3-tetrafluoro
Propyl methacrylate, 2,2,3,4,4,4-f
Xafluorobutyl methacrylate, urethane acryle
Macromolecules synthesized from compounds containing
However, the present invention is not limited to this. The polymer used in the present invention is light or purple.
When using an external curing monomer, the light or
UV initiator is used. The initiator may be a seed
Are available, for example, 2,2-diet
Xyacetophenone, 2-hydroxy-2-methyl-1
-Phenyl-1-one, 1- (4-isopropylphenyi)
-)-2-hydroxy-2-methylpropan-1-o
, 1- (4-dodecylphenyl) -2-hydroxy-
Acetophenones such as 2-methylpropan-1-one,
Benzoin methyl ether, benzoin ethyl ether
Benzoin, benzyldimethyl ketal
Zophenone, benzoylbenzoic acid, 4-phenylbenzo
Phenone, 3,3-dimethyl-4-methoxybenzofe
Benzophenones such as nonone, thioxanthone, 2-chloro
Thio such as luthioxanthone and 2-methylthioxanthone
Xanthone, diazonium salt, sulfonium salt,
Iodonium salts, selenium salts and the like can be used. In addition, how to rise liquid crystal molecules immediately after voltage application
As another method to solve the problem caused by
The present invention relates to a liquid crystal display device that limits the rising direction of liquid crystal molecules.
A driving method is also provided. In the driving method of the liquid crystal display device according to the present invention,
Is a region where the rising direction of liquid crystal molecules is different between two substrates
Low-level voltage applied to liquid crystal display devices
In this state, a voltage higher than the threshold of the liquid crystal molecules is applied.
You. Here, “low-level voltage” refers to
This is the voltage level when the applied voltage is the lowest. FIG. 1 shows a method of driving the liquid crystal display device of the present invention.
The description will be made with reference to FIG. FIG. 13 (a) shows the present invention.
In a method of manufacturing a liquid crystal display device, an electric current applied to a liquid crystal cell is
FIG. 13B shows an example of a pressure waveform.
5 is an example of an applied voltage waveform used for driving a display device.
High level, low level voltage is normally white mode
Corresponds to black display and white display, respectively. Applied voltage and transmission through the liquid crystal cell shown in FIG.
The relationship between the rates will be described with reference to FIG. The applied voltage in the conventional driving waveform is B-shaped.
State and the C state. In state B
This includes the case where the applied voltage is 0 V.
In, the liquid crystal molecules are parallel to the substrate surface. Therefore,
When the applied voltage is changed from B to C, standing of liquid crystal molecules occurs.
The rising direction can be two directions, and the rising direction is different.
Light leakage occurs at the boundary of the
A slow response on the order of seconds and a change in viewing angle characteristics occur. On the other hand, the driving of the liquid crystal display device of the present invention was performed.
In the operation method, when a low level voltage is applied,
Also applies a voltage A higher than the threshold voltage of the liquid crystal molecules.
It is characterized by the following. The applied voltage A is the threshold voltage of the liquid crystal molecules.
Liquid crystal molecules in the A state
It is already a little up in one direction. others
Therefore, even if a high level voltage C is applied, the A state
Liquid crystal molecules while maintaining the rising direction of the liquid crystal molecules at
The liquid crystal rises and the liquid crystal molecules rise when a large voltage is applied.
The upward direction is defined as one direction. This allows the liquid crystal molecules
The rising direction is defined as one direction, and the
No boundary area occurs, and light leakage and boundary movement
Slow response on the order of seconds, and no change in viewing angle characteristics. The device of the present invention is used for a TFT (thin film).
mtransistor (thin film transistor)
In order to drive the liquid crystal, the liquid crystal has a large electric resistance.
It is required that the charge retention rate be high. Therefore,
It is a liquid crystal material with high resistance such as fluorine and chlorine
The charge retention characteristics do not decrease due to visual rays or UV irradiation
Things are desirable. In the liquid crystal optical element of the present invention, the liquid
By using a compensator between the crystal cell and the polarizing film.
In addition, the viewing angle characteristics can be improved. Compensator for this
Is to compensate for the liquid crystal having a positive refractive index anisotropy
Therefore, a compensator having a negative refractive index anisotropy is desired.
Good. In particular, in a liquid crystal display device in which four regions coexist
Offset the problem of coloring in oblique directions due to its symmetry
As a result, good viewing angle characteristics without coloring can be obtained. Also,
Each micro area corresponding to the four micro areas of the liquid crystal layer
Alignment films having different properties are particularly desirable. In addition, the optical axis
It is also desirable to use a compensating plate that is tilted for this purpose. In particular, FIGS.
In a liquid crystal display device in which the four regions shown in FIG.
The problem of coloring in the oblique direction is also suppressed from the
Especially desirable. Also consider the rising direction of liquid crystal molecules
Use a compensator whose optical axis is inclined from the vertical direction.
Can also be. Japanese Patent Application Laid-Open
A row disclosed in Japanese Patent Application Laid-Open No. 6-222213.
Drawn between rolls with different rotating speeds
Lum etc. can be used. By using the present invention as described above,
By the same simple method as the conventional twisted nematic liquid crystal device
Wide viewing angle and high contrast liquid crystal display device that can be manufactured
Can be obtained. EXAMPLES The present invention will be described below in detail with reference to examples.
However, the present invention is not limited to the following examples unless it exceeds the gist.
It is not limited. (Embodiment 1) The size of one pixel is 100 μm
× 300μm, pixel number 480 × 640 × 3, display screen
240mm diagonal amorphous silicon thin film tiger
A substrate having a transistor array was used. After the two substrates 23 and 33 have been cleaned,
Mid orientation agent JALS-428 (Nippon Synthetic Rubber) 21,3
1 by spin coating and baking at 90 ° C and 220 ° C.
Performed. Thereafter, the buffed cloth made of rayon is used for laminating.
Bing treatment was performed. The rubbing direction of each substrate should be
The diagonal direction of the substrate so that it is sometimes 90 °. Board
Apply adhesive to the periphery and use a 6 μm diameter
Tex ball was sprayed. Next, the pixel structure on both substrates is
Adjust the position so that it is aligned, and stick together while applying pressure
Was. The bonded substrates are placed in a vacuum chamber,
After evacuation, nematic liquid crystal (ZLI4792 manufactured by Merck)
11 were injected. Nematic liquid crystals have a natural pitch length
Mix the chiral agent (S811) so that the thickness becomes 70 μm.
Was. After implantation, heat the device to 90 ° C and then cool to room temperature
Rejected. The prepared liquid crystal element was examined with an optical microscope (polarized light).
Observed. In each pixel, the alignment is uniform when no voltage is applied.
Are separated into two types of regions A and B when a voltage is applied.
Was observed. Two types of observations from tilting the stage
Confirmed that the rising direction of liquid crystal molecules was opposite in the region
did it. The two regions were stable with no change over time. The manufactured liquid crystal display device is biased to cross Nicol.
After installing the light plate, install it on the rotating stage, in front of it
Install a color luminance meter (BM-5A, manufactured by Topcon Corporation)
The viewing angle dependence of the crystal display device was examined. 8th floor on LCD screen
Tone display was performed, and the viewing angle dependency at each gradation display was measured. Sight
The level relation of the brightness between the gray levels is inverted within the range of the angle within 40 °.
I never did. Substrate without Thin Film Transistor Array
(30 mm x 40 mm), an alignment film was prepared in the same
m Create a cell using the spacer,
The pretilt angle was 0.05 ° when measured by the pre-tilt method. (Example 2) Compensation having negative refractive index anisotropy
As a compensation plate, the minor axis of the refractive index ellipsoid of the compensator is the film surface
Film that is perpendicular to the surface (VAC manufactured by Sumitomo Chemical Co., Ltd.)
-100) was used to study the effect of the compensator. Example
In a liquid crystal display device manufactured under the same conditions as
A compensator was attached between the filter and the polarizing plate. Use color luminance meter
And the visual angle dependent control was measured.
No reversal of the luminance order between gradations occurred. Also, diagonally
The contrast from the direction was better as compared with the first embodiment.
Was. Comparative Example 1 A general-purpose polyimide alignment film (Japanese
Except that this synthetic rubber AL1051) was used,
An element was produced in the same manner as in Example 1. Observe under a polarizing microscope
In addition, only a uniform region was observed when a voltage was applied. The viewing angle was measured in the same manner as in Example 1.
Then, within a viewing angle of 10 °, the inversion of the luminance order between gradations is
occured. The pretilt angle of this alignment film was 1.0 °.
Was. Example 3 Polystyrene was used as the alignment film.
Other than using a xylene solution and setting the firing temperature to 120 ° C
Produced an element in the same manner as in Example 1. Under a polarizing microscope
Observation shows that two regions with different rising directions when voltage is applied
Was observed and stable. The viewing angle is measured in the same manner as in Example 1.
And the order relationship of luminance between gradations within a viewing angle of 40 ° or less.
It did not flip. The pretilt angle is 0.0
7 °. (Embodiment 4) As a liquid crystal to be injected, ZLI
4792 and 4,4'-diacryloyloxybiphenyl
Acrylate (1 wt% based on liquid crystal)
Mixed solution of chill ether (1 wt% based on monomer)
A device was produced in the same manner as in Example 1, except that was used.
Furthermore, after sealing the injection hole, ultraviolet rays were irradiated at room temperature.
The device remained transparent even after the irradiation with ultraviolet rays. Polarized light microscope
Observed below, when voltage is applied to each pixel,
Two types of regions with different upward directions are observed and voltage is applied
Immediately after, no movement of the boundary was observed, and it was stable. The viewing angle is measured in the same manner as in Example 1.
And the order relationship of luminance between gradations within a viewing angle of 40 ° or less.
It did not flip. (Embodiment 5) As a liquid crystal to be injected, ZLI
KAYARAD PET-30 (Nippon Kayaku)
0.2% by weight, Irganox 907 (monomer
Example 1 except that a mixed solution of 1 wt%) was used.
An element was produced in the same manner as in Example 1. The obtained panel is used as a liquid crystal phase.
Heat to 100 ° C above the phase transition temperature of the isotropic phase.
UV light (0.1 mW / cm ^Two ). afterwards,
Cool panel at 10 ° C / min while applying voltage of 5V
did. Multiple regions were observed in each pixel. Obtained
FIGS. 15 and 16 show polarization microscope photographs of one pixel of the device.
Show. FIG. 15 shows a photograph when no voltage is applied. FIG.
6 is a view obtained by obliquely tilting the panel when 3 V is applied.
Thus, different tones indicate different orientation states. In a tilted state
Observation reveals four small areas with different rising directions of liquid crystal molecules
Is confirmed to be present. Immediately after voltage application
There is a part where the areas where the rising direction differs in the torsion direction
However, after a while, the border disappears and the same screw
Structure where the rising direction differs in the direction of contact
Changed to The viewing angle was measured in the same manner as in Example 1.
Then, within the range of the viewing angle of 50 ° or less, the relation of the luminance order between the gradations
The clerk did not reverse. A liquid crystal evaluation device (LCD-5000)
FIG. 14 shows the transmittance-voltage curve in the vertical direction of the substrate measured in
Show. Almost the same characteristics as those of the TN device are obtained, and the applied voltage is 5
The contrast at V was greater than 200: 1. In addition, when viewing at a gray scale display at an azimuth angle of 45 °,
The angular characteristics were measured (FIGS. 17-19). In all directions
Almost the same viewing angle characteristics are obtained, and within 50 °
No halftone reversal was obtained. The contrast of the obtained device (1 V / 5
V) is shown in FIG. 20 as a conoscopic image. Etc. contra
The strike curve is almost circular, and is almost
It can be seen that they have the same viewing angle characteristics. (Example 6) The panel manufactured in Example 5
At different cooling rates (1 ° C / min to 20 ° C / min)
Debated. As the cooling rate increases, the size of the minute area increases
Has become smaller. (Example 7) The panel manufactured in Example 5 was used.
While changing the applied voltage (2V, 3V, 5V, 10V
V) Upon cooling, the higher the voltage, the smaller
The size was small, and the structure of FIG. 3 was likely to occur. (Example 8) If the monomer content is 0.1%
The same method as in Example 5 except that the temperature was changed from 1.0% to 1.0%.
To produce a panel (cooling rate 10 ° C./min). monomer
The higher the content, the smaller the size of the microregion
Was. When the monomer content is 0.5 wt% or more
Means that the rising direction of the liquid crystal molecules is
Boundary of the area that is defined and has the same twist but different rising directions
No part was observed, but at 0.3 wt% or less, the voltage
A boundary portion moving with time immediately after the application was observed. (Example 9) The device obtained in Example 5 was
Level voltage is higher than the threshold voltage of the liquid crystal molecules.
When driven, a high level voltage is applied immediately.
Later, the rising direction of the liquid crystal molecules is defined in one direction,
No decrease in trust, no change in viewing angle characteristics over time
Was. FIG. 21 shows the difference between the response curves with and without voltage application.
You. Those without low level voltage are on the order of seconds.
Low level while transmittance changes slowly
In which a voltage of 1.6 V is applied,
No slow response is observed. (Comparative Example 2) Except that ultraviolet rays were irradiated at room temperature
In the same manner as in Example 5, a panel was produced. UV illumination
Since the orientation of the liquid crystal at the time of shooting is stored,
It was difficult to control the size. (Embodiment 10) Room temperature, voltage application (10 V)
Panels were prepared in the same manner as in Example 5 except that UV irradiation was performed below.
Was prepared. Change the cooling rate and applied voltage during cooling
As a result, panels with different sizes of minute regions can be obtained.
Was. (Example 11) Conditions and modes of ultraviolet irradiation
Example 5 was repeated except that the nomer content was 0.5 wt%.
Similarly, a panel was produced. UV irradiation (0.1mW / cm
^Two ) Was irradiated for 3 minutes as the first step. This allows
The small area has been stably present, but immediately after voltage application
The rising position of the liquid crystal molecules is arbitrary and "white" state
The boundary was generated and it was observed to move. Second stage
UV light was applied for 60 minutes at room temperature. The resulting device is
The rise immediately after voltage application is fixed, and the viewing angle characteristics are all
The directions were almost the same. The TFT substrate on which the above-mentioned alignment film was formed,
-Using a filter substrate,
Created a flannel. After cooling, the same structure as in FIG.
Was confirmed. When viewing angle characteristics are measured, viewing angle is 60 °
The brightness order does not reverse within the range
The last was also 150: 1. In the same manner as in Example 1,
The measured pretilt angle was almost 0 °.
Was. (Example 12) "X" -type width 5 was applied to the entire surface electrode.
The alignment substrate 33 (FIG. 22) on which a number of μm openings are arranged.
(A): A portion of the substrate is enlarged and displayed) and the size of one pixel
Are 100 μm × 100 μm at 10 μm intervals.
A plurality of alignment substrates 23 (FIG. 22B) are used as substrates.
Used. After cleaning these substrates, the polyimide alignment agent
Spin JALS-428 (Japan Synthetic Rubber) 21, 31
Apply with a coat and bake at 90 ° C and 220 ° C
Was. After this, a rubbing treatment was performed using a buff cloth made of rayon.
Was applied. The rubbing direction is the diagonal direction of the substrate.
The rubbing direction between the side substrate and the lower substrate forms an angle of 90 °.
Swelling. Apply adhesive to the periphery of the board and
Latex spheres having a diameter of 6 μm were applied as a sensor. Continued
And the center of the electrode whose electrode opening is 100 μm × 100 μm
The two substrates were bonded together under pressure so as to come to a position. The bonded substrates are placed in a vacuum tank,
After evacuation, nematic liquid crystal (ZLI4792 manufactured by Merck,
Phase transition temperature: 92 ° C) UV curable monomer (KAYAR
ADPET-30 (Nippon Kayaku) 0.2 wt%) started
Agent (Irganox 907, 5 wt.
%) Was injected. 1 panel obtained
Heat to 10 ° C, and at that temperature, UV (0.1 mW / cm
^Two ) Was irradiated for 30 minutes. Then, 8V, 10Hz sine
The substrate was cooled at 20 ° C./min while applying a wave voltage. Profit
A polarizing microscope photograph of the cell obtained is shown in FIG. FIG.
The cell was tilted slightly and photographed with an intermediate voltage applied. 10
Each 0 μm × 100 μm section follows the “x” shaped opening.
It can be seen that it is divided into four small regions. C
From the change in brightness when tilting
It was confirmed that the rising direction was as shown in FIG.
Also, the boundary between a 100 μm × 100 μm section and the next section
An area with a different twisting direction enters the area.
At the boundary between pixels when sufficient voltage is applied.
No light leakage was observed. This is shown in FIG.
A region or B region between C region and D region of the next section
The liquid crystal is twisted in the same direction,
The liquid crystal of the present invention in which regions in different upward directions are not connected by a line
This is because the display device has a characteristic structure.
You. Also, the rising direction of the liquid crystal immediately after voltage application is sufficient.
The rising direction of the liquid crystal after a certain time has elapsed.
Light leakage did not occur. In addition,
Four small areas disappear even if pressure is repeatedly turned on and off
I never did. [0143] A polarizing plate was mounted on the prepared cell in crossed Nicols.
After mounting, set on the rotating stage, color brightness in front of it
(BM-5A manufactured by Topcon) and a liquid crystal display
Was examined for viewing angle dependence. 8 gradations are displayed on the LCD screen
At 45 ° azimuth intervals, the viewing angle dependency at each gradation display is
It was measured. Viewing angle within 60 ° in all directions
There is no inversion of the brightness relationship between gray levels
Was. Also, it was measured with a liquid crystal evaluation device (LCD-5000).
The contrast at a substrate vertical applied voltage of 5 V is 2
00: 1 or more. Embodiment 13 One pixel has a size of 100 μm.
m × 300μm, pixel number 480 × 640 × 3, display screen
Amorphous silicon thin film with a diagonal size of 240 mm
A substrate having a transistor array (TFT) was used. Up
There is an RGB color filter on the side substrate,
It is a pole (counter electrode) and has no opening. On the other hand,
There are TFTs, gate lines, drains in addition to pixel electrodes.
There is a line. After cleaning these substrates, the polyimide alignment agent
Apply JALS-428 (Japanese synthetic rubber) by spin coating
The fabric was baked at 90 ° C and 220 ° C. afterwards,
Rabin on each substrate with buff cloth made of rayon
Treatment. The rubbing direction of each board is
In the diagonal direction of the substrate so as to be 90 ° at the time of alignment. Base
Adhesive is applied to the periphery of the board, and the diameter is 6 μm as a spacer
Latex balls were sprayed. Next, the pixel structure on both substrates
Adjust the position so that the structures match,
I let you. When the concentration of the ultraviolet monomer is
Except for 0.3 wt%, the liquid crystal solution was the same as in Example 1.
Was injected. The panel obtained is heated to 100 ° C.
UV at a temperature of 0.2mW / cm ^Two ) For 60 minutes
Was. After that, a gate line of 33 Hz, 15 V of 32 μs was applied.
Apply 33Hz, 8V rectangular wave to pulse wave and drain line
While heating, the heater was removed and the mixture was allowed to cool to room temperature. Got
Image of one pixel of a liquid crystal display device observed with a polarizing microscope
24. Due to the non-uniform electric field between the counter electrode and the pixel electrode
Each pixel is slightly irregular, but divided into four small areas.
Cracked. From the same observation as in Example 1, four minute
The region is a region where the rising directions of the liquid crystal molecules are different,
Regions with different twist directions exist alternately, with the same twist direction,
The two areas having the opposite rising directions were in contact only at points. Ma
In addition, when the rising direction of the liquid crystal immediately after voltage application is sufficient
It is the same as the rising direction of the liquid crystal after the passage of the
This did not occur. Furthermore, long-time voltage ON-OFF
Does not disappear in the four small areas
Was. The viewing angle characteristics and the front
When measuring the trust, the viewing angle is 60 ° in all directions
There is no gradation inversion within 5% and the contrast at 5 V is 15
0: 1. Comparative Example 3 A voltage was not applied during cooling.
Except for the above, a liquid crystal display device was manufactured in the same manner as in Example 13. cold
Four areas with different rising directions coexisted after rejection
However, the four types of regions are random regardless of the pixel shape.
Shape. When voltage is applied,
There was a part that rises in the expected direction, but inside the pixel
Does not show regularity in the liquid crystal rising direction
Was. Also, after a sufficient time has passed since the voltage was applied,
Also, many boundaries where light leakage occurred were observed. Oblique viewing angle
According to the observation from the direction, this boundary is the twist direction of the liquid crystal.
Are the same, and are boundaries between areas with different rising directions.
Was confirmed. Furthermore, immediately after the voltage is applied,
Moving, moving slowly towards a stable place
It was allowed to go. The front contrast was measured in the same manner as in Example 12.
At the time when a sufficient time has passed after the voltage was applied.
Even 50: 1. (Comparative Example 4) After irradiation with ultraviolet rays at room temperature,
Except for the above, a liquid crystal display device was prepared in the same manner as in Example 12. Electric
Even after heating and cooling under pressure, the twist direction of the liquid crystal is different.
The area shown in FIG.
No microregions were found. How to twist this liquid crystal
The structure in which areas with different directions are scattered
It was expected that the state at room temperature was memorized. Implementation
When the viewing angle characteristics were measured in the same manner as in Example 12, the viewing angle was 10
There was a direction in which gradation inversion occurred at °. (Example 14) Low pretilt polyimide
As alignment films, two types of alignment films (TAL10 manufactured by Hoechst)
07 and Toray K104 treated with ethyl lactate
) And the monomer concentration was 0.5 wt%
A device was prepared in the same manner as in Example 12, except for the above. Example
Similar to Example 12, four micro regions were expressed, and
Similar viewing angle characteristics were obtained. Measure the pretilt angle
Then, TAL1007 and K104 are each 0.35
° and 0.5 °. (Comparative Example 5) General-purpose polyimide alignment film (Japanese
Except that this synthetic rubber AL1051) was used,
An element was produced in the same manner as in No. 12. Observe under a polarizing microscope
Immediately after the voltage application, a plurality of regions occurred, but soon
It disappeared and only a uniform area was observed. The viewing angle is measured in the same manner as in Example 12.
Then, within a viewing angle of 10 °, the inversion of the luminance order between gradations occurs.
There was a twisting direction. The pretilt angle of this alignment film is 1.
0 °. (Embodiment 15)
The liquid crystal panel has an ultraviolet monomer concentration of 1.0 wt%
A liquid crystal solution similar to that in Example 12 was injected except that the above-mentioned conditions were satisfied.
The panel obtained is heated to 100 ° C.,
Line (0.2mW / cm ^Two ) Was irradiated for 5 minutes. Then implemented
Example 1 and 33Hz, 15V 32μs pulse on gate line
Apply a 33Hz, 10V triangular wave to the wave and drain lines
Next, the heater was removed, and the mixture was allowed to cool to room temperature. In this state
The structure shown in FIG. 24 was observed in the pixel. Then room temperature
Under UV light (0.1mW / cm ^Two ) For 120 minutes
Was. The obtained liquid crystal display had the same viewing angle as that of Example 13.
Had properties. Further, this liquid crystal display device is
After heating to ℃ and holding for 10 minutes, no voltage is applied
And cooled. After cooling, when observed with a polarizing microscope,
24, the structure shown in FIG. 24 was observed. (Example 16) Polystyrene as an alignment film
The xylene solution was used and the firing temperature was set to 120 ° C.
Except for this point, an element was produced in the same manner as in Example 12. Polarized light microscope
Observed below, when voltage is applied, four different rising directions
Was observed and stable. The viewing angle is measured in the same manner as in Example 12.
Then, the relationship of the luminance order between gradations within the viewing angle of 60 °
Did not reverse. Further, the pretilt angle is set to 0.1.
07 °. (Embodiment 17) As a liquid crystal to be injected, ZL
I4792 and 4,4'-diacryloyloxybiphenyl
Acrylate (0.3wt% based on liquid crystal), benzo
Mixing of inmethyl ether (1 wt% based on monomer)
A device was fabricated in the same manner as in Example 12 except that the mixed solution was used.
Made. The viewing angle is measured in the same manner as in Example 12.
Then, the relationship of the luminance order between gradations within the viewing angle of 60 °
Did not reverse. (Example 18) The concentration of the ultraviolet monomer was
0 wt%, 0.01 wt%, 0.02 wt%, respectively
Example 1 except that 0.05 wt% and 0.1 wt% were used.
A liquid crystal cell was prepared in the same manner as in No. 2. In any cell
Also, a structure similar to that of FIG. 23 was generated. But the voltage
When ON-OFF is repeated, the UV monomer concentration becomes 0 w
t%, 0.01 wt% liquid crystal cell
A part where the region disappeared was observed. (Example 19) The concentration of the ultraviolet monomer was
2 wt%, 4 wt% and 10 wt%, respectively,
Except that the irradiation time was set to 5 minutes,
A cell was prepared. When the monomer concentration is 2 wt% and 4 wt%,
23, a structure similar to that of FIG. 23 was generated.
In a cell with a monomer concentration of 10 wt%, the alignment of the liquid crystal
Was distorted and many areas were not twisted by 90 °.
Thus, no white state was obtained even when no voltage was applied. (Example 20) In the same manner as in Example 12,
Aldrich polyvinyl cinnamate only for alignment film
Chlorobenzene / methylene chloride 1/1 mixed solution
Liquid (2 wt%), sintering temperature to 90 ° C, Rabin
Irradiation with linear polarized light of ultraviolet light was performed instead of irradiation. Linearly polarized
The direction was the same as the rubbing direction. As in the first embodiment
A liquid crystal panel was manufactured. Structure similar to FIG.
The order is not reversed within the viewing angle range of 60 °.
And the contrast was 200: 1. The linearly-polarized light
Measurement of the pretilt angle in the direction perpendicular to the polarization direction
The angle was almost 0 °. (Example 21) In the same manner as in Example 20,
Polyvinyl cinnamate applied and exposed to linearly polarized light
Then, 1 wt% of a photopolymerization initiator (Irgacure 65)
1,4-di- (4- (6-acrylyl) mixed with 1)
oyloxyhexyloxy) benzoloxy)
apply benzene and heat to 50 ° C,
Irradiated with light and returned to room temperature. This enables nematic liquid crystal
In the phase, the orientation remained fixed on the substrate surface. This
This is exactly the same process using a glass substrate for testing.
It could be confirmed by polarization microscope observation. As described above, the present invention relates to the conventional
As simple as a twisted nematic liquid crystal display
Liquid crystal display with wide viewing angle and high contrast that can be manufactured using
Provide equipment.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an enlarged perspective view of a liquid crystal layer of a liquid crystal display device of the present invention. FIG. 2 is a sectional view showing a liquid crystal display device of the present invention. FIG. 3 is an enlarged view of a liquid crystal layer of the liquid crystal display device of the present invention when viewed from a direction perpendicular to a substrate. FIG. 4 is an enlarged top view of a liquid crystal layer of the liquid crystal display device of the present invention. FIG. 5 is a sectional view showing a liquid crystal display device of the present invention. FIG. 6 is a sectional view of the liquid crystal display device showing a splay arrangement. FIG. 7 is a diagram showing a relationship between a rubbing direction and a spray arrangement. FIG. 8 is an enlarged top view of a liquid crystal layer of the liquid crystal display device of the present invention. FIG. 9 is a sectional view showing a liquid crystal display device of the present invention. FIG. 10 is a diagram showing the behavior of liquid crystal molecules at the boundary between regions where the liquid crystal twist direction is the same and the rising directions of the liquid crystal molecules are different. (A) When no voltage is applied (b) When voltage is applied FIG. 11 is a diagram showing behavior of liquid crystal molecules at a boundary portion of a region where liquid crystal molecules have different twist directions and different rising directions of the liquid crystal molecules. (A) When no voltage is applied (b) When voltage is applied FIG. 12 is a cross-sectional view showing a liquid crystal display device of the present invention containing a polymer. FIG. 13 is a diagram of waveforms used in a method for driving a liquid crystal display device of the present invention. FIG. 14 is a transmittance-voltage curve of the liquid crystal display device of the present invention. FIG. 15 is a polarization microscope photograph of one pixel of the liquid crystal display device of the present invention. FIG. 16 is a polarization microscope photograph of one pixel of the liquid crystal display device of the present invention (tilted). FIG. 17 is a diagram showing viewing angle characteristics of the liquid crystal display device of the present invention. FIG. 18 is a diagram showing viewing angle characteristics of the liquid crystal display device of the present invention. FIG. 19 is a diagram showing viewing angle characteristics of the liquid crystal display device of the present invention. FIG. 20 is a diagram showing the contrast of the liquid crystal display device of the present invention. FIG. 21 is a diagram of a response curve when a voltage higher than a threshold voltage is applied at a low level. FIG. 22 is a diagram showing an electrode shape of a substrate used in Example 1. FIG. 23 is a polarization microscope photograph of the liquid crystal display device of the present invention. FIG. 24 is an enlarged view of one pixel of the liquid crystal display device of the present invention obtained in Example 2. FIG. 25 is a sectional view of a conventional liquid crystal display device (with no voltage applied). FIG. 26 is a cross-sectional view for explaining a problem of a conventional liquid crystal display device (voltage application). FIG. 27 is a perspective view of a conventional liquid crystal display device. FIG. 28 is a top view of a conventional liquid crystal display device. FIG. 29 is a cross-sectional view of a conventional liquid crystal display device. FIG. 30 is a diagram showing a conventional liquid crystal display device. FIG. 31 is a view showing a problem of a conventional liquid crystal display device. [Description of Signs] 11 Liquid crystal molecule 12 Polymer 13 Pretilt angle 21, 31 Alignment film 22, 32 Transparent electrode 23, 3 Glass substrate 34 Rubbing direction 35 Electrode opening 41, 42 Light rays A, B, C, D Different alignment Rubbing direction of micro area aa ', bb' substrate

Continuation of front page (58) Field surveyed (Int.Cl. ⁶ , DB name) G02F 1/1337

Claims (1)

(57) Claims 1. In a liquid crystal display device in which a liquid crystal layer made of a nematic liquid crystal is sandwiched between two substrates, two kinds of liquid crystal molecules having different rising directions in the liquid crystal layer. A liquid crystal display device characterized by having irregular minute regions coexist. 2. A liquid crystal display device in which a liquid crystal layer is interposed consisting nematic liquid crystal between two substrates, one of Rabin
Orientation that two kinds of rising directions can coexist stably
A liquid crystal display device having a film, wherein a minute region having a different twist direction of a liquid crystal alignment vector and a minute region having a different rising direction of liquid crystal molecules coexist in the liquid crystal layer. 3. The liquid crystal layer has a total of four types of micro regions, that is, micro regions having different twisting directions of liquid crystal alignment vectors and micro regions having different rising directions of liquid crystal molecules. Liquid crystal display device. 4. A micro-region having a different orientation vector twisting direction of a liquid crystal and a micro-region having different rising directions of liquid crystal molecules.
4. The liquid crystal display device according to claim 2, wherein the two minute regions coexist in one pixel of the liquid crystal layer. 5. The liquid crystal display device according to claim 2, wherein said minute area has an irregular shape. 6. The liquid crystal display device according to claim 1, wherein the surfaces of the two substrates are each subjected to an alignment treatment in one direction. 7. The liquid crystal device according to claim 1, wherein the liquid crystal molecules have the same torsion direction of the alignment vector, and each of the regions having different rising directions of the liquid crystal molecules is not in contact with a line on a virtual plane crossing the liquid crystal layer. The liquid crystal display device according to claim 1. 8. An alignment film for aligning liquid crystal molecules on at least one of the two substrates, wherein a pretilt angle of the alignment film is 0.5 ° or less. The liquid crystal display device according to claim 1. 9. An alignment film for aligning liquid crystal molecules on at least one of the two substrates, wherein the alignment film has a property of aligning the liquid crystal molecules in a direction perpendicular to the rubbing direction. The liquid crystal display device according to any one of claims 1 to 8, wherein: 10. The liquid crystal display device according to claim 1, wherein the liquid crystal layer contains a chiral agent having a twist direction in which the liquid crystal has a splay arrangement. 11. A region in which the electrodes on the two substrates have different shapes or at least one of the electrodes on the substrate has an opening and an uneven electric field is generated between the two substrates. 2. The method according to claim 1, wherein:
0. The liquid crystal display device according to any one of 0. 12. The liquid crystal display device according to claim 1, wherein a small amount of a polymer is present in the liquid crystal layer. 13. The liquid crystal display device according to claim 12, wherein the amount of the polymer present in the liquid crystal layer is 0.02% by weight or more and 4% by weight or less. 14. A liquid crystal according to claim 1, wherein a compensator having a negative refractive index anisotropy is disposed on one or both sides of said two substrates. Display device. 15. A combination in which two kinds of minute regions having different rising directions of liquid crystal molecules or a minute region having different twisting directions of liquid crystal orientation vectors and four kinds of minute regions having different rising directions of liquid crystal molecules are formed. A liquid crystal or a liquid crystal solution containing a small amount of a monomer or an oligomer is injected between the two substrates, and then, under a voltage application, a temperature from a temperature equal to or higher than the liquid crystal phase-isotropic phase transition temperature to a temperature lower than the phase transition temperature. Liquid crystal characterized by cooling the liquid crystal layer to generate two types of micro regions having different rising directions of liquid crystal molecules or four types of regions having different twist directions of liquid crystal alignment vectors and different rising directions of liquid crystal molecules. A method for manufacturing a display device. 16. A combination of two types of minute regions having different rising directions of liquid crystal molecules, or a plurality of minute regions having different twisting directions of liquid crystal orientation vectors and four types of minute regions in the rising direction of liquid crystal molecules. A method of injecting a liquid crystal solution containing a small amount of a monomer or an oligomer between the two substrates, and thereafter reacting the monomer or the oligomer to form a polymer. 17. The liquid crystal display device according to claim 15, wherein said monomer or oligomer is reacted at a temperature not lower than the liquid crystal phase-isotropic phase transition temperature of liquid crystal to produce a polymer. Production method. 18. The method according to claim 15, wherein said monomer or oligomer is reacted under voltage application to form a polymer.
A method for manufacturing a liquid crystal display device according to any one of claims 1 to 17. 19. The method for manufacturing a liquid crystal display device according to claim 15, wherein said monomer or oligomer is reacted at least twice. 20. A method of driving a liquid crystal display device in which minute regions having different rising directions of liquid crystal molecules coexist when a voltage is applied, wherein a voltage equal to or higher than a threshold voltage of the liquid crystal molecules is applied even when a low level voltage is applied. A method for driving a liquid crystal display device, comprising: 21. A liquid crystal or a small amount of an object between two substrates.
Inject a liquid crystal solution containing
Temperature above the phase transition temperature of the isotropic phase to below the phase transition temperature
Cooling the liquid crystal layer down to the point where the liquid crystal molecules rise
Regions with different orientations or how the orientation vector of liquid crystal is twisted
Liquid crystal display characterized by generating regions with different directions
Device manufacturing method. 22. A liquid crystal or a small amount of an object is provided between two substrates.
Inject a liquid crystal solution containing
Under pressure application, regions where the rising directions of liquid crystal molecules are different,
Is the torsion direction of the liquid crystal orientation vector and the
A liquid characterized by generating regions having different upward directions
Manufacturing method of crystal display device.