JP4364542B2 - Liquid crystal display device and manufacturing method thereof - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a liquid crystal display device and a method for manufacturing the same, and more particularly to a liquid crystal display device comprising a liquid crystal panel that simultaneously realizes high transmittance, high-speed response, and wide viewing angle by controlling the alignment of liquid crystal molecules by polymerizing monomers. It relates to a manufacturing method.
[0002]
[Prior art]
In a liquid crystal panel, two substrates with an electrode with an alignment film formed on the surface are opposed to the alignment film side, and a liquid crystal having positive or negative dielectric anisotropy is sealed in the gap between the opposing substrates. On one substrate, a plurality of pixels composed of substantially rectangular electrodes are arranged. The liquid crystal display device regulates the alignment of liquid crystal molecules in the liquid crystal by controlling the voltage applied between each pixel electrode and the electrode facing the liquid crystal panel to control the alignment of the liquid crystal molecules in the liquid crystal panel. By doing so, the display is performed.
[0003]
Examples of the orientation include horizontal orientation and vertical orientation. Among liquid crystal panels currently in practical use, typical methods (modes) using horizontal alignment are TN (twisted nematic) mode and IPS (in-plane switching) mode, and typical methods using vertical alignment are used. Is a multi-domain vertical alignment (MVA) mode.
[0004]
The active matrix type liquid crystal display is mainly in the TN mode but has a narrow viewing angle characteristic. Therefore, currently, a technique called an IPS mode and an MVA mode is employed for a liquid crystal panel that exhibits a wide viewing angle characteristic comparable to that of a CRT, and is currently widely used for various applications.
[0005]
FIG. 1 is an explanatory diagram of a first control means for horizontal alignment.
[0006]
Currently, a horizontal alignment control means widely employed is to perform a rubbing process on a horizontal alignment control film (hereinafter simply referred to as a horizontal alignment film). As shown in FIG. 1, rubbing treatment is rubbing the surface of an alignment control film (hereinafter simply referred to as an alignment film) in one direction with a cloth such as nylon or rayon, and liquid crystal molecules are aligned in the rubbing direction. To do. The rubbing treatment has problems such as dust and dust coming out of the cloth adhering to the substrate surface, and rubbing unevenness, and display defects tend to occur. Further, in order to realize multi-domain, a plurality of regions subjected to rubbing processing in different directions must be mixed in a pixel, which requires a very complicated process and is difficult in practical use.
[0007]
FIG. 2 is an explanatory diagram of the second control means for horizontal orientation.
[0008]
As a means for controlling horizontal alignment instead of rubbing, there is light irradiation. As shown in FIG. 2, the alignment is controlled by irradiating the surface of the horizontal alignment film with polarized or non-polarized ultraviolet light from one direction. Since this method is non-contact, it is expected to improve the productivity as compared with the rubbing treatment, but at present, it does not reach a practically sufficient level in terms of uniformity of alignment and stability.
[0009]
In the IPS mode, liquid crystal molecules are switched in a horizontal plane by a comb-shaped electrode. However, the comb-shaped electrode significantly reduces the aperture ratio, so that a strong backlight is required. In the MVA mode, the liquid crystal is aligned approximately perpendicularly to the substrate, and the alignment of liquid crystal molecules is defined by a protrusion or a slit provided in a transparent electrode (ITO).
[0010]
On the other hand, a vertical alignment control film (hereinafter simply referred to as a vertical alignment film) is used for controlling the vertical alignment. Only the vertical alignment film cannot control the direction in which the liquid crystal molecules tilt when a voltage is applied. Like the horizontal alignment, the tilt direction can be controlled by rubbing or light irradiation, but it is not practical for the same reason as the horizontal alignment.
[0011]
3A and 3B are explanatory diagrams of the MVA mode of vertical alignment, where FIG. 3A is a diagram showing a voltage off state between electrodes, and FIG. 3B is a diagram showing a voltage on state between electrodes.
[0012]
In the MVA mode liquid crystal panel using the vertical alignment, as shown in FIG. 3, the direction in which the liquid crystal molecules tilt when a voltage is applied is controlled by protrusions and depressions formed on the substrate surface, or slits provided on the electrodes. Yes. In this case, multi-domain can be realized by devising the pattern of protrusions and slits.
[0013]
In the MVA mode liquid crystal panel, liquid crystal molecules in the vicinity of the protrusions and slits start to tilt when voltage is applied, and the behavior propagates to other liquid crystal molecules. Therefore, in order to increase the response to voltage, it is desirable to form protrusions and slits densely. However, since the transmittance of the protrusions and slits is reduced, the transmittance decreases as the density increases. That is, it is difficult to achieve both high transmittance and high-speed response. Further, in order to form the protrusions and slits, a process using photolithography is necessary, and the process becomes complicated.
[0014]
Although the decrease in the actual aperture ratio due to the projections and slits in the MVA mode is not as high as that in the IPS mode comb electrode, the light transmittance of the liquid crystal panel is lower than that in the TN mode. Therefore, in order to employ it in a notebook computer that requires low power consumption, an improvement in transmittance is desired.
[0015]
The current MVA mode has a low viewing angle because the banks and ITO slits are arranged in a complicated manner so that the liquid crystal molecules tilt in four directions when a voltage is applied to widen the viewing angle. If this is simplified and the bank or ITO slit gap is widened, the light transmittance can be increased. However, if the gap between the bank or the ITO slit is very wide, it takes time to propagate the tilt of the liquid crystal molecules, so that the panel response is very slow when a voltage is applied.
[0016]
Therefore, the structure as shown in FIG. 4 was considered in which the bank was abandoned and the liquid crystal molecules fell in four directions when a voltage was applied. In the structure shown in FIG. 4, the liquid crystal molecules fall in parallel to the ITO slit, but the direction of the fall is determined by the electric field at the ITO end and propagates in the direction of the fall toward the center of the pixel.
[0017]
In consideration of this, a technique was introduced in which liquid crystal containing a polymerizable monomer was injected, the monomer was polymerized in a state where a voltage was applied, and the direction in which the liquid crystal molecules fell was stored (according to the applicant of the present application). (See Patent Application No. 2002-136128).
[0018]
FIG. 4 is a diagram showing a pixel electrode structure having a fine slit.
[0019]
In this technique, a pixel structure having a fine slit as shown in FIG. 4 is applied in order to define the alignment direction of the liquid crystal. When a voltage was applied, the liquid crystal molecules fell down and stabilized in four directions a, b, c, and d shown in FIG. 4 parallel to the fine slits, and alignment division could be realized.
[0020]
[Patent Document 1]
JP-A-9-281472
It does not disclose a technique for regulating the alignment of liquid crystal molecules.
[0021]
[Patent Document 2]
JP 2001-264784 A (refer to the specification and claims 25 to 27).
[0022]
A technique for performing a polymerization process of a liquid crystal composition containing a monomer and / or an oligomer while irradiating with light is disclosed.
[0023]
[Problems to be solved by the invention]
When applying the pixel as shown in FIG. 4 disclosed in the patent application No. 2002-136128 proposed by the applicant of the present application, although a higher transmittance than that of the MVA can be realized, the fine slit width greatly affects the optical characteristics. Variations in the optical characteristics among the liquid crystal panels are increased. In addition, since there is no electrode in the slit portion, the electric field applied to the liquid crystal molecules is weak, and the driving voltage becomes high, so that the power consumption increases.
[0024]
The electrodes are made by photolithography. However, if a mask having the same size as that of the liquid crystal panel is used, the cost increases. Therefore, the exposure is performed a plurality of times while shifting the position of the small mask. Therefore, a subtle difference in each exposure affects the optical characteristics, the pixel electrodes are finished somewhat unevenly, and a tile-like pattern appears faintly on the liquid crystal panel. Further, since the faint film thickness distribution of the resist material used in photolithography affects the finished dimensions of the electrodes, subtle unevenness occurs when halftone display on the entire surface of the liquid crystal panel is performed.
[0025]
As described above, it is difficult for the conventional alignment control means to simultaneously achieve alignment stability, uniformity, high transmittance, high-speed response, and wide viewing angle.
[0026]
Therefore, an object of the present invention is to provide a liquid crystal panel comprising a liquid crystal panel manufactured by a novel alignment control means that is excellent in alignment stability and uniformity, and that can simultaneously achieve high transmittance, high-speed response, and a wide viewing angle. It is to provide a display device.
[0027]
[Means for Solving the Problems]
The method of manufacturing a liquid crystal display device according to the present invention that achieves the above object is to provide a substrate having two electrodes with an alignment film formed on the surface, with the alignment film side facing each other, and providing a gap between the opposing substrates. A liquid crystal panel in which a plurality of pixels made of the electrodes are aligned is provided on one of the substrates, and both the pixel electrodes and the electrodes facing the same are provided. In the method of manufacturing a liquid crystal display device that regulates the orientation of liquid crystal molecules in the liquid crystal by controlling the voltage applied between the electrodes, the liquid crystal panel encapsulates a liquid crystal composition containing a polymerizable monomer; And a step of polymerizing the monomer by irradiating light from a direction inclined with respect to the normal direction of the liquid crystal panel surface.
[0028]
In the liquid crystal display device according to the first aspect of the present invention that achieves the above object, two substrates having electrodes with alignment films formed on the surface are opposed to the alignment film side, and a gap is formed between the opposed substrates. A plurality of pixels comprising a substantially rectangular electrode on one of the substrates, the liquid crystal containing a polymerizable monomer having a negative dielectric anisotropy and being polymerizable in the gap; In a liquid crystal display device that regulates the orientation of liquid crystal molecules in the liquid crystal by controlling a voltage applied between the pixel electrode and an electrode opposite to the pixel electrode. Is characterized in that the monomer is polymerized by irradiating light, and the director of the liquid crystal molecules in the domain is oriented in a direction where the first tilt angle θ1 with respect to the pixel electrode is less than 90 °. To do.
[0029]
In the liquid crystal display device, each of the pixels is divided into domains cut by a plurality of line segments extending radially on the surface from the center point of the surface of the pixel electrode, and the liquid crystal molecules in the domain The director has an azimuth angle φ on the surface that is different between adjacent domains, is substantially oriented in a direction centering on the center point of the surface of the pixel electrode, and a boundary area that occupies the boundary between adjacent domains and the vicinity thereof A director of a certain liquid crystal molecule faces a direction of a second tilt angle θ2 different from the first tilt angle θ1.
[0030]
In the liquid crystal display device according to the second aspect of the present invention that achieves the above object, the two substrates having the electrodes with the alignment film formed on the surface are opposed to the alignment film side, and a gap is formed between the opposing substrates. A liquid crystal panel in which a plurality of pixels composed of substantially rectangular electrodes are aligned on one of the substrates, and a liquid crystal having negative dielectric anisotropy is sealed in the gap. A liquid crystal display device that regulates the orientation of liquid crystal molecules in the liquid crystal by controlling a voltage applied between the pixel electrode and an electrode facing the pixel electrode. An insulating material that is encapsulated in a liquid crystal composition and is irradiated with light in a state in which a voltage is applied between the electrodes to polymerize the monomer, and is aligned in parallel on the surface of the pixel electrode. It is equipped with a plurality of bank-like structures made and the front The liquid crystal is divided into domains cut by a plurality of line segments extending radially from the center point of the surface of the pixel electrode, and the bank-like structure is aligned with the bank-like structure for each domain. The directions are different, and when a voltage is applied between the electrodes, the liquid crystal molecules in the liquid crystal corresponding to the pixels are inclined in a direction substantially parallel to the bank-like structure. .
[0031]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. First, the case where the alignment film is a vertical alignment film will be described.
[0032]
FIG. 5 is a diagram showing a method according to the present invention for regulating the alignment of liquid crystal molecules using an electrode with a vertical alignment film. FIG. 5A shows the state of the liquid crystal molecules when no voltage is applied to the liquid crystal layer. (B) is a figure which shows the state of a liquid crystal molecule when a voltage is applied to a liquid-crystal layer.
[0033]
As shown in FIG. 5A, in a liquid crystal panel in which a liquid crystal composition containing a monomer polymerizable by light and having a negative dielectric anisotropy is sealed between substrates on which a vertical alignment film is formed. The monomer is polymerized by irradiating light from a direction inclined with respect to the normal direction of the liquid crystal panel surface (the inclination angle with respect to the normal is α). The vertical alignment film is not subjected to an alignment control process such as a rubbing process. At this time, it is desirable that no voltage is applied to the liquid crystal layer, that is, the liquid crystal molecules are aligned substantially perpendicular to the substrate surface.
[0034]
When a voltage is applied to the liquid crystal layer in the liquid crystal panel manufactured by the process as described above, the liquid crystal molecules are inclined in the direction of light irradiation as shown in FIG. can get. That is, it is possible to control the tilt direction of the liquid crystal molecules even though the alignment control process is not performed on the vertical alignment film.
[0035]
Next, the case where the alignment film is a horizontal alignment film will be briefly described.
[0036]
FIG. 6 is a diagram showing a method according to the present invention for regulating the alignment of liquid crystal molecules using an electrode with a horizontal alignment film. FIG. 6A shows the state of the liquid crystal molecules when no voltage is applied to the liquid crystal layer. (B) is a figure which shows the state of a liquid crystal molecule when a voltage is applied to a liquid-crystal layer.
[0037]
As shown in FIG. 6A, in a liquid crystal panel in which a liquid crystal composition containing a monomer polymerizable by light and having a positive dielectric anisotropy is sealed between substrates on which a horizontal alignment film is formed. The monomer is polymerized by irradiating light from a direction inclined with respect to the normal direction of the liquid crystal panel surface (the inclination angle with respect to the normal is α). The horizontal alignment film is subjected to an alignment control process such as a rubbing process. At this time, it is desirable that no voltage is applied to the liquid crystal layer, that is, the liquid crystal molecules are aligned substantially horizontally with respect to the substrate surface.
[0038]
In the liquid crystal panel manufactured by the above-described process, when a voltage is applied to the liquid crystal layer, as shown in FIG. 6B, the liquid crystal molecules are tilted in the direction of light irradiation, and uniform monodomain alignment is achieved. can get. That is, it is possible to control the tilt direction of the liquid crystal molecules.
[0039]
Hereinafter, in the embodiment of the present invention, only the case where the alignment film is a vertical alignment film will be described for convenience.
[0040]
FIG. 7 is a diagram showing the relationship between the light irradiation angle with respect to the normal line of the liquid crystal panel surface and the tilt angle of the liquid crystal molecules. The liquid crystal panel was manufactured by changing the light irradiation angle α with respect to the normal line of the liquid crystal panel surface shown in FIGS. 5 and 6, and the tilt angle φ of the liquid crystal molecules in a state where no voltage was applied in the manufactured liquid crystal panel was examined. The results are shown in FIG. The tilt angle φ is an angle of the liquid crystal molecules with respect to the substrate surface. In the case of complete vertical alignment, the tilt angle is 90 °.
[0041]
By irradiating the liquid crystal panel surface with light obliquely, the liquid crystal molecules are slightly tilted in the light irradiation direction, and the tilt angle φ of the liquid crystal molecules becomes smaller than 90 °. This defines the tilt direction of the liquid crystal molecules when a voltage is applied. The greater the tilt angle α, the smaller the tilt angle φ, that is, the liquid crystal molecules are tilted more with respect to the vertical.
[0042]
FIG. 8 is a diagram showing another method according to the present invention for regulating the alignment of liquid crystal molecules. According to this method, the tilt angle can be controlled in a wider range. In this method, as shown in FIG. 8, in the step of polymerizing the monomer by irradiating the liquid crystal panel with light, the voltage α is not applied to the liquid crystal layer, but the angle α with respect to the normal direction of the liquid crystal panel surface. After irradiating light from a tilted direction, it is possible to control the tilt angle over a wider range by irradiating light in a state where a voltage is applied to the liquid crystal layer, for example, from the normal direction of the liquid crystal panel surface. .
[0043]
First, the direction in which the liquid crystal molecules should be tilted is defined by irradiating light from a direction inclined by an angle α with respect to the normal direction of the liquid crystal panel surface in a state where no voltage is applied to the liquid crystal layer. Thereafter, when a voltage is applied, the liquid crystal molecules are tilted in a direction defined by oblique irradiation. By further irradiating light in that state, for example, from the normal direction of the liquid crystal panel surface, the polymerization of the monomer proceeds while the liquid crystal molecules are tilted, so the tilt angle is further reduced, that is, the tilt angle from the vertical is further increased. Can be bigger. The tilt angle can be controlled by changing the monomer concentration, the initial oblique irradiation conditions, the subsequent voltage application conditions, the irradiation conditions at that time, and the like.
[0044]
FIG. 9 is a diagram illustrating a method of manufacturing a multi-domain liquid crystal panel. As shown in FIG. 9, in the display area of the liquid crystal panel, that is, in the area corresponding to the pixel electrode, the liquid crystal panel has at least two domains by mixing a plurality of areas with different directions in which the liquid crystal is irradiated with light. A multi-domain liquid crystal panel can be realized.
[0045]
As a specific example of the method for manufacturing the liquid crystal panel, FIG. 9A shows an example in which light is irradiated through an optical layer having a plurality of inclined surfaces, and FIG. 9C shows an example in which light is irradiated a plurality of times from different directions using a mask provided with a light shielding layer. FIG. 9C shows a mask using a mask partially provided with a light shielding layer. An example is shown in which light is irradiated obliquely through the panel, and then the entire panel surface is irradiated with light from different directions.
[0046]
It was found that once the tilt direction of the liquid crystal molecules was defined by oblique irradiation, the initially defined tilt orientation was maintained even when light was irradiated from a different direction. A specific example of the method for manufacturing the liquid crystal panel shown in FIG. 9C utilizes this property.
[0047]
Further, it is also possible to realize multi-domain by combining domain regulation means such as protrusions, depressions formed on the substrate surface, or slits provided on the electrodes with the present invention.
[0048]
According to the present invention, it is not necessary to perform any alignment control processing on the alignment film formed on the substrate, it is not necessary to provide domain control means such as protrusions and electrode slits, and the process after assembling the liquid crystal panel. The alignment of the liquid crystal can be controlled. Therefore, the present invention has a simple manufacturing process and very excellent orientation controllability.
[0049]
In addition, according to the present invention, since it is easy to control the tilt angle of liquid crystal molecules and to make it multi-domain, it is possible to easily realize a high transmittance, a high-speed response, and a wide viewing angle.
[0050]
Further, according to the present invention, stable and uniform alignment can be realized regardless of the shape and unevenness of the liquid crystal interface. For example, it is possible to easily realize excellent orientation even when unevenness is formed on the surface like a reflective electrode of a reflective panel.
[0051]
FIG. 10 is a plan view showing the structure of one substrate of the liquid crystal panel according to the present invention. FIG. 10 shows a configuration of a liquid crystal panel corresponding to three pixels separated by gate bus lines. The substrate of this liquid crystal panel is formed with gate bus lines and data bus lines arranged in a matrix, and the gate bus lines and data bus lines are connected to pixel electrodes via TFT (Thin Film Transistor) elements. A Cs electrode is formed at the center of the pixel electrode. On the other substrate, a color filter and a common electrode are formed over the entire display area.
[0052]
A vertical alignment film is formed on both substrates. Both substrates are bonded to each other through a spacer, and a liquid crystal composition in which diacrylate is mixed at a concentration of 0.3 wt% in a nematic liquid crystal having negative dielectric anisotropy is sealed to produce a liquid crystal panel.
[0053]
Thereafter, a step of irradiating the liquid crystal panel with ultraviolet rays to polymerize diacrylate is performed, and polarizing plates (polarizing elements) are arranged on both sides of the liquid crystal panel so that the absorption axes are orthogonal to each other.
[0054]
Next, the process of irradiating the liquid crystal panel with ultraviolet rays will be described.
[0055]
As shown in FIG. 8, in the state where no voltage is applied to the liquid crystal layer, ultraviolet rays are emitted from the direction of α = 35 ° with respect to the normal direction of the liquid crystal panel surface at 1 J / cm. ² After irradiation, UV is applied at 3 J / cm from the normal direction (α = 0 °) of the liquid crystal panel surface with a voltage of 20 V applied to the liquid crystal layer. ² Irradiate. Thereby, a monodomain alignment with a tilt angle of 87 ° is obtained.
[0056]
FIG. 11 is an explanatory diagram of a method for realizing a liquid crystal panel having two domains. (I) shows the first step and (II) shows the second step. As shown in FIG. 11, in this method, the liquid crystal is irradiated with ultraviolet rays in the order of steps I and II.
[0057]
Step I: Direction of 35 ° with respect to the normal direction of the liquid crystal panel surface with no voltage applied to the liquid crystal layer through a mask in which an opening is provided only in the region corresponding to the upper half of one pixel UV rays from 2J / cm ² Irradiate.
[0058]
Step II: UV light is applied to the entire surface of the liquid crystal panel at an angle of 35 ° relative to the normal direction of the liquid crystal panel surface with no voltage applied to the liquid crystal layer and from the direction opposite to the irradiation direction in step I at 4 J / cm. ² Irradiate.
[0059]
Thereby, a two-domain alignment with a tilt angle of 89 ° is obtained.
[0060]
FIG. 12 is an explanatory diagram of a method for realizing a liquid crystal panel having four domains, (I) shows the first step, (II) shows the second step, (III) shows the third step, (IV) is a diagram showing a fourth step. As shown in FIG. 12, in this method, the liquid crystal is irradiated with ultraviolet rays in the order of steps I, II, III, and IV.
[0061]
Step I to Step IV: With respect to the normal direction of the liquid crystal panel surface in a state where no voltage is applied to the liquid crystal layer through a mask in which an opening is provided only in a region corresponding to ¼ of one pixel. 1J / cm from 35 ° ² Irradiate.
[0062]
As shown in the drawing, the irradiation directions of the ultraviolet rays are different from each other in the steps I to IV, and the irradiation directions are set to the azimuth angle φ on the liquid crystal panel surface in the order of the steps I, II, III, and IV. The rotation direction is about 45 degrees, 135 degrees, 225 degrees, and 315 degrees counterclockwise with respect to the line.
[0063]
After that, UV is applied to the entire surface of the liquid crystal panel from the normal direction of the liquid crystal panel surface with a voltage of 20V applied to the liquid crystal layer. ² Irradiate. Thereby, a 4-domain alignment with a tilt angle of 87 ° is obtained.
[0064]
As described above, according to the present invention, it is possible to provide a liquid crystal display device composed of a liquid crystal panel that is excellent in alignment controllability of liquid crystal molecules and can simultaneously realize high transmittance, high-speed response, and a wide viewing angle. Become.
[0065]
Next, a liquid crystal panel divided into four domains for each pixel according to the present invention will be described in detail below.
[0066]
FIG. 13 is a diagram illustrating a state of liquid crystal molecules in a portion corresponding to one pixel of the liquid crystal panel divided into four domains. As shown in FIG. 13, the pixel is divided into four domains cut by a plurality of line segments extending radially from the center point O of the surface of the pixel electrode, and a director of liquid crystal molecules in each domain. The azimuth angle φ with respect to the gate bus line on the surface differs by 90 ° between adjacent domains, and is substantially in the direction of centripetal centering on the surface of the pixel electrode.
[0067]
The directors of the liquid crystal molecules in the boundary between adjacent domains and in the boundary occupying the vicinity thereof are oriented in a direction of a second tilt angle (θ2: not shown) different from the first tilt angle (θ1: not shown). .
[0068]
In the rectangular pixel electrode as shown in FIG. 13 in which the fine slit as shown in FIG. 4 is not provided, the present invention has an inclination angle with respect to the substrate of liquid crystal molecules in the vicinity of the substrate within one pixel electrode after normal monomer polymerization. There are multiple, here four.
[0069]
Next, the movement of the liquid crystal molecules shown in FIG. 13 will be described. In a vertically aligned liquid crystal panel using a liquid crystal having a negative dielectric constant, liquid crystal molecules fall from vertical to horizontal when a voltage is applied between the electrodes.
[0070]
FIG. 14 is a diagram showing the orientation of liquid crystal molecules on each side around the pixel electrode. In the case of the pixel as shown in FIG. 14, the azimuth angle direction in which the liquid crystal molecules are tilted is approximately perpendicular to the side of the pixel electrode immediately after voltage application. As a result, the azimuth angle direction in which the liquid crystal molecules inside the pixel electrode fall also falls substantially perpendicular to the pixel electrode.
[0071]
Eventually, the liquid crystal molecules falling from each side collide with each other inside the pixel electrode, and the liquid crystal molecules can be balanced. As a result, it tilts in the 45 ° direction with respect to the pixel electrode side, and finally the orientation is divided into four in the oblique 45 ° direction as shown in FIG. When light, for example, ultraviolet rays is irradiated in this state, the alignment direction of the liquid crystal is fixed by the polymerized polymer, and light is transmitted when a polarizing plate having a polarization axis parallel to the bus line is attached to the liquid crystal panel.
[0072]
However, as shown in FIG. 13, the pixel electrode end and the central portion were not oriented in the 45 ° direction, and the overall transmittance was reduced. For this reason, the orientation control may be performed by introducing a fine slit as shown in FIG. 4 proposed in the patent application No. 2002-136128 (prior invention of the present applicant) by the applicant of the present invention. Therefore, it has been desired to make the pixel electrode structure as simple as possible.
[0073]
Therefore, without providing the fine slits as shown in FIG. 4, a means for giving the liquid crystal molecules the orientation to obtain the maximum transmittance by partially changing the tilt angle of the liquid crystal molecules with respect to the substrate was taken. The present invention.
[0074]
This means will be described in detail in the following examples. In all of the following examples, a vertical alignment film is used, the liquid crystal has a negative dielectric anisotropy, and the polarizing plate is attached to both sides of the liquid crystal panel in a crossed Nicols state. The direction is parallel to the bus line. The panel size is 15 inches and the resolution is XGA.
[0075]
Below, the 1st-6th Example which concerns on the 1st structure of this invention is demonstrated in detail.
[0076]
First, the first embodiment will be described.
[0077]
FIG. 15 is a diagram showing a first embodiment of the liquid crystal panel of the present invention. As shown in FIG. 15, this liquid crystal panel has a data bus line and a gate bus line intersecting substantially vertically on one substrate, and has a substantially rectangular transparent pixel electrode between both bus lines. A region corresponding to a cross that intersects the center point of the surface of the pixel electrode is divided into four domains. Hereinafter, these four domains are referred to as region A, and the boundary region is referred to as region B. As shown in FIG. 15, the angle of the liquid crystal molecules in the vicinity of the substrate in a cross shape is substantially vertical, and the other portions are inclined at 88 °. This was realized as follows.
[0078]
Using a cross mask as shown in FIG. 15, first, ultraviolet rays are irradiated in a state where a voltage is applied to the liquid crystal layer. As a result, the portion through which the ultraviolet rays are transmitted becomes stable with the liquid crystal molecules tilted. Further, when the mask is removed and ultraviolet rays are applied without applying a voltage, the liquid crystal molecules in the periphery of the pixel are stably aligned in a state substantially perpendicular to the substrate. These irradiations are performed from the normal direction of the substrate surface.
[0079]
In the region (domain) A where the ultraviolet rays are first irradiated, the liquid crystal molecules are inclined in the direction of 45 degrees with respect to the bus line. The orientation of the liquid crystal molecules is defined by the first exposure, and the orientation is maintained even by the second exposure. In the region (boundary region) B that is exposed to ultraviolet rays for the first time in the second exposure, the alignment is defined with the liquid crystal molecules approximately vertical. When the liquid crystal is driven after the panel is completed, the liquid crystal molecules in the region A are tilted in the 45 ° direction with respect to the bus line, and the liquid crystal molecules in the region B are affected by this, and the liquid crystal molecules in the region A fall down. As a result, it tilts at 45 ° to the bus line. Compared with the case where a voltage is applied before ultraviolet irradiation (FIG. 13), the region inclined in the 45 ° direction becomes wider, and high transmittance can be realized. In addition, since there are four inclination directions within one pixel, a phenomenon of darkening in a cross shape occurs at the boundary. That is, no light is transmitted near the cross.
[0080]
In addition, when irradiating ultraviolet rays for the second time, only the region B may be irradiated. Alternatively, only the region B may be irradiated with ultraviolet light without applying a voltage between the electrodes in the first irradiation, and only the region A may be irradiated with a voltage applied between the electrodes with the second irradiation. Note that the region B is a region to be exposed without applying a voltage to the liquid crystal layer.
[0081]
Next, a second embodiment will be described.
[0082]
FIG. 16 is a diagram showing a second embodiment of the liquid crystal panel of the present invention. As shown in FIG. 16, the angle of the liquid crystal molecules in the vicinity of the substrate on the cross on the pixel electrode and in the vicinity of the long side (data bus line) of the pixel is substantially perpendicular to the substrate, and the other part is 88 ° with respect to the substrate. Tilted. The manufacturing method is the same as in the first embodiment.
[0083]
The liquid crystal molecules in the vicinity of the long side of the pixel do not tilt in the 45 ° direction with respect to the bus line. Therefore, the orientation of liquid crystal molecules in the vicinity of the long side of the pixel is defined in a direction substantially perpendicular to the substrate. When the liquid crystal is driven after the panel is completed, the liquid crystal molecules in the region A are inclined at 45 ° with respect to the bus line, and the liquid crystal molecules in the region B are affected by this, and the liquid crystal molecules in the region A fall down. As a result, it tilts in the direction of 45 ° to the bus line. Compared to when the voltage is applied in the first embodiment (FIG. 15), the region inclined in the 45 ° direction becomes wider, and the transmittance can be improved. Note that the region B is a region to be exposed without applying a voltage to the liquid crystal layer.
[0084]
Next, a third embodiment will be described.
[0085]
FIG. 17 is a diagram showing a third embodiment of the liquid crystal panel of the present invention. As shown in FIG. 17, the angle of the liquid crystal molecules in the vicinity of the substrate with respect to the substrate in the square-shaped region on the pixel electrode was inclined substantially vertically, and the other portions were inclined at 88 °. The manufacturing method is the same as in the first embodiment.
[0086]
Although the third embodiment is different from the second embodiment in that the vicinity of the pixel electrode is also masked in addition to the cross, the reason for masking the vicinity of the pixel electrode is described below. Liquid crystal molecules in the vicinity of the pixel electrode do not tilt in the 45 ° direction with respect to the bus line. Therefore, the orientation of liquid crystal molecules in the vicinity of the periphery of the pixel electrode is defined in a direction substantially perpendicular to the substrate. Further, the liquid crystal molecules near the corner of the pixel electrode are inclined in the 45 ° direction with respect to the bus line. Therefore, the liquid crystal molecules in the vicinity of the corners of the pixel electrode are exposed in a state where a voltage is applied, and the orientation direction is defined. When the liquid crystal is driven after the panel is completed, the liquid crystal molecules in the region A are inclined at 45 ° with respect to the bus line, and the liquid crystal molecules in the region B are affected by this, and the liquid crystal molecules in the region A fall down. As a result, it tilts in the direction of 45 ° to the bus line.
[0087]
Compared to when a voltage is applied in the second embodiment (FIG. 16), in the second embodiment, the region inclined in the 45 ° direction becomes wider and the transmittance can be further improved. Note that the region B is a region to be exposed without applying a voltage to the liquid crystal layer.
[0088]
Next, a fourth embodiment will be described.
[0089]
FIG. 18 is a diagram showing a fourth embodiment of the liquid crystal panel of the present invention. As shown in FIG. 18, the angle of the liquid crystal molecules in the vicinity of the substrate with respect to the substrate in the shape of a square shape on the pixel electrode except for the four corners was substantially vertical, and the other portions were inclined at 88 °. The manufacturing method is the same as in the first embodiment.
[0090]
Liquid crystal molecules in the vicinity of the corners of the pixel electrode are inclined in a 45 ° direction with respect to the bus line. Therefore, the liquid crystal molecules in the vicinity of the corners of the pixel electrode are exposed with a voltage applied to define the alignment direction. The other orientation directions are the same as those in the third embodiment. In this way, the four corners of the square shape on the pixel electrode are surely tilted to 45 °, so there is no need to mask here. When the liquid crystal is driven after the panel is completed, the liquid crystal molecules in the region A are inclined in the 45 ° direction with respect to the bus line, and the liquid crystal molecules in the region B are also inclined in the 45 ° direction with respect to the bus line. Compared to when a voltage is applied in the third embodiment (FIG. 17), the region inclined in the 45 ° direction becomes wider, and the transmittance can be further improved. Note that the region B is a region to be exposed without applying a voltage to the liquid crystal layer.
[0091]
Next, a fifth embodiment will be described.
[0092]
FIG. 19 is a view showing a fifth embodiment of the liquid crystal panel of the present invention. As shown in FIG. 19, the pixel electrode is provided with a groove in the direction of 45 ° with respect to the bus line in the liquid crystal panel cross-sectional direction. This is realized by patterning the insulating layer between the metal layer and the transparent electrode (pixel electrode). As shown in FIG. 19, the pixel electrode itself has fine irregularities, and the liquid crystal molecules fall along the irregularities.
[0093]
Since the distance between the protrusions is narrow, when the liquid crystal molecules fall in a direction approximately perpendicular to the groove, the liquid crystal molecules collide with the liquid crystal molecules that have fallen due to the influence of the adjacent grooves, and finally the liquid crystal molecules fall in a direction parallel to the protrusions.
[0094]
Next, a sixth embodiment will be described.
[0095]
FIG. 20 is a diagram showing a sixth embodiment of the liquid crystal panel of the present invention. As shown in FIG. 20, a spacer (also called a bead) that keeps the gap between the two substrates was disposed only on the TFT. Compared with a liquid crystal panel having a spacer on the pixel electrode, the alignment disorder can be suppressed. Spacers are placed at the four corners of each pixel electrode or at the four corners of a plurality of pixels. Due to the arrangement of the spacers, no spacers are provided in the display area of the pixels, so that the spacers do not affect the alignment of the liquid crystal molecules, and therefore the spacers do not affect the photochemical characteristics of the liquid crystals.
[0096]
As described above, according to the first configuration of the present invention, the liquid crystal panel in which the monomer is mixed is irradiated with light in a state where the vicinity of the cross of the pixel electrode and the region B near the bus line and the gate line are masked. Thus, the liquid crystal molecules can stand vertically in the vicinity of the electrode surface in the vicinity, and the orientation is defined in a predetermined direction in the non-masked region A of the pixel electrode, so that the liquid crystal is driven after the liquid crystal panel is completed. Then, the liquid crystal molecules in the region A are tilted in a predetermined direction with respect to the bus line, and the liquid crystal molecules in the region B are also tilted in the same direction in response to the tilt of the liquid crystal molecules in the region A. To come.
[0097]
Below, the 2nd structure of this invention is demonstrated.
[0098]
The second configuration of the present invention is a substitute for a fine electrode in place of the liquid crystal alignment control using the slit-shaped electrode as shown in FIG. 4 proposed in the above-mentioned prior application of the present applicant. As a means, the following structure is provided. As shown in FIG. 21 (first embodiment), a fine bank-like structure is provided, or a bank-like unevenness is provided on the transparent electrode itself (not shown) to control the orientation direction. Alternatively, as shown in FIGS. 22 and 23 (second and third embodiments), a transparent electrode is provided on a fine bank-like structure, and the transparent electrode is uneven. Or as shown in FIG. 24 (4th Example), a bank is provided in the opposing side and 4 division | segmentation is implement | achieved.
[0099]
The movement of the liquid crystal molecules in the second configuration of the present invention will be described below.
[0100]
In a vertically aligned liquid crystal panel using a liquid crystal having a negative dielectric constant, liquid crystal molecules are tilted when a voltage is applied between the electrodes. In FIG. 4, the liquid crystal molecules are tilted in a direction parallel to the fine electrodes. However, in the case of the pixel as shown in FIG. 4, the width of the fine electrode changes due to a slight process variation. As a result, the electric field changes and the optical characteristics of the panel change. In order to solve this problem, it is necessary to build in the panel a structure that determines the orientation direction without using fine electrodes.
[0101]
As shown in FIG. 21, when a fine bank is arranged on the electrode, the liquid crystal molecules are inclined in a direction perpendicular to the bank, but the distance between the adjacent banks is small and the liquid crystal molecules collide with each other. Eventually, the liquid crystal molecules tilt in a direction parallel to the bank. Since the bank mainly determines the direction in which the liquid crystal molecules fall, even if the width of the bank changes, the effect on the optical characteristics is small compared to when the width of the electrode in FIG. 4 changes.
[0102]
Similarly, although not shown, when the transparent electrode itself is provided with bank-like irregularities, the liquid crystal molecules fall in a direction parallel to the bank-like irregularities, but the bank mainly determines the direction in which the liquid crystal molecules fall. In addition, since the orientation state is determined by the electric field, even if the width of the bank changes, the influence on the optical characteristics is small compared to when the width of the electrode shown in FIG. In addition, in order to provide bank-like unevenness on the transparent electrode itself, there is a manufacturing method such as arranging a fine bank on a substrate and forming a transparent electrode thereon.
[0103]
Furthermore, as shown in FIGS. 22 and 23, when a fine bank is arranged on a substrate and a transparent electrode is provided thereon, electric lines of force penetrate the surface of the bank vertically, so that a voltage is applied between the substrates. At the moment, the direction in which the liquid crystal molecules fall is undefined. For this reason, liquid crystal molecules that are tilted in the opposite direction are also generated and stabilized, and the assumed alignment may not be obtained. Therefore, by providing an insulating layer on the transparent electrode, if the electric lines of force are not perpendicular to the bank surface and enter the liquid crystal at a certain angle, the direction in which the liquid crystal molecules fall is uniquely determined, and the assumed orientation Can be obtained.
[0104]
Furthermore, as shown in FIG. 24, even when a bank is provided on the opposite side, the direction in which the liquid crystal molecules are tilted by the bank without using fine electrodes, that is, the orientation can be regulated.
[0105]
Hereinafter, first to fourth embodiments according to the second configuration of the present invention will be described in detail. Note that all examples use a vertical alignment film, the liquid crystal has negative dielectric anisotropy, and the polarizing plate is attached to both sides of the liquid crystal panel with loss nicol, so normally black, and the polarizing axis of the polarizing plate is on the bus line. It is parallel to the direction. It is an active matrix type with a panel size of 15 inches and a resolution of XGA.
[0106]
First, a liquid crystal panel in which the alignment of liquid crystal is regulated by the method of the prior invention of the present applicant will be described.
[0107]
A panel in which a transparent electrode having a structure having a fine slit as shown in FIG. 4 was provided on the substrate on the side having the TFT element was produced. As the liquid crystal, a material obtained by mixing 0.3 wt% of a diacrylate monomer with a liquid crystal composition having a negative dielectric anisotropy was used. After injecting the liquid crystal, ultraviolet rays were applied while applying a voltage between the substrates to define the alignment direction of the liquid crystal.
[0108]
This panel had a contrast of 700 and a response speed of 15 ms rise and 10 ms fall.
[0109]
In this panel, since the electro-optical characteristics differ for each exposure at the time of electrode formation, a tile-like pattern was seen when halftone display was performed on the entire surface. In addition, unevenness was observed when halftone display was performed on the entire surface.
[0110]
Next, a first embodiment will be described.
[0111]
FIG. 21 is a view showing the liquid crystal panel of the first embodiment according to the second configuration of the present invention, (A) is a plan view of the transparent electrode on the side where the TFT element is present, and (B) is (A). It is sectional drawing of the liquid crystal panel cut | disconnected by the L1-L2 line in FIG.
[0112]
As shown in FIG. 21, a panel in which a fine bank-like structure was provided on the transparent electrode 1 on the side where the TFT element was provided was produced. As the liquid crystal 2, a material obtained by mixing 0.3 wt% of a diacrylate monomer with a liquid crystal composition having a negative dielectric anisotropy was used.
[0113]
After injecting the liquid crystal, ultraviolet rays were applied while applying a voltage between the transparent electrode 1 of the glass substrate (substrate) 3 and the transparent electrode 1 ′ of the glass substrate (substrate) 4 to define the alignment direction of the liquid crystal 2.
[0114]
In this liquid crystal panel, the alignment can be regulated by tilting the liquid crystal molecules in parallel with the bank near the bank 5 without providing a fine slit. An alignment film 6 is provided on the outermost surface of the substrate (the surface in contact with the liquid crystal) including the bank 5. As a result, when halftone display was performed on the entire surface, a tile-like pattern (pattern) generated in the liquid crystal panel provided with the fine slits shown in FIG. 4 was not seen. Further, when halftone display was performed on the entire surface, no unevenness was observed. An alignment film 6 ′ is also provided on the transparent electrode 1 ′.
[0115]
Similarly, a panel in which a fine bank-like structure as shown in FIG. 21 was provided on the counter substrate instead of on the transparent electrode on the side where the TFT element was provided was produced. The transparent electrode on the TFT substrate side was left in a rectangular shape without slits. The bank-like structure was arranged so as to protrude 4 microns from the transparent electrode on the opposite TFT substrate side. Even in this panel, even when halftone display was performed on the entire surface, a tile-like pattern like a liquid crystal panel was not visible.
[0116]
Further, when halftone display was performed on the entire surface, no unevenness was observed.
[0117]
Next, a second embodiment will be described.
[0118]
FIG. 22 is a view showing a liquid crystal panel of a second embodiment according to the second configuration of the present invention, (A) is a plan view of the transparent electrode on the side where the TFT element is present, and (B) is (A). It is sectional drawing of the liquid crystal panel cut | disconnected by the L1-L2 line in FIG.
[0119]
As shown in FIG. 22, a fine bank-like structure was provided on the substrate on the side where the TFT element is provided, and a panel provided with a transparent electrode thereon was produced. As the liquid crystal, a material obtained by mixing 0.3 wt% of a diacrylate monomer with a liquid crystal composition having a negative dielectric anisotropy was used.
[0120]
When a voltage was applied between the substrates after liquid crystal injection, it took several tens of seconds to several minutes to determine the orientation direction. Thereafter, ultraviolet rays were irradiated to define the alignment direction of the liquid crystal.
[0121]
In this panel, as in the first embodiment, the alignment can be regulated by tilting the liquid crystal molecules in parallel with the bank in the vicinity of the bank without providing a fine slit. As a result, a tile-like pattern as generated in the liquid crystal panel provided with the fine slits shown in FIG. 4 was not seen. Further, when halftone display was performed on the entire surface, no unevenness was observed.
[0122]
Similarly, a fine bank-like structure as shown in FIG. 22 was provided on the counter substrate instead of the substrate on the side where the TFT element was provided, and a panel provided with a transparent electrode thereon was produced. The transparent electrode on the TFT substrate side was left in a rectangular shape without slits. The bank-like structure was arranged so as to protrude 4 microns from the transparent electrode on the opposite TFT substrate side. Also in this panel, halftone display was performed on the entire surface, and a tile-like pattern as generated in the liquid crystal panel provided with the fine slits shown in FIG. 4 was not seen. Further, when halftone display was performed on the entire surface, no unevenness was observed.
[0123]
Next, a third embodiment will be described.
[0124]
FIG. 23 is a diagram showing a liquid crystal panel of a third embodiment according to the second configuration of the present invention, (A) is a plan view of the transparent electrode on the side where the TFT element is present, and (B) is (A). It is sectional drawing of the liquid crystal panel cut | disconnected by the L1-L2 line in FIG.
[0125]
As shown in FIG. 23, a fine bank-like structure is provided on the substrate on the side where the TFT element is provided, a transparent electrode is provided thereon, and a planarization layer is provided by planarizing the transparent electrode with an insulating material. A panel was produced. As the liquid crystal, a material obtained by mixing 0.3 wt% of a diacrylate monomer with a liquid crystal composition having a negative dielectric anisotropy was used. The direction of the electric lines of force entering the liquid crystal layer by this flattening layer enters the liquid crystal layer at an angle where the electric lines of force are not perpendicular to the bank surface as compared with the second embodiment, so that a voltage was applied between the electrodes. Sometimes the direction in which the liquid crystal molecules fall is determined, and the liquid crystal molecules fall with good responsiveness.
[0126]
When a voltage was applied between the substrates after liquid crystal injection, it took several seconds to 10 seconds to determine the alignment direction. Thereafter, ultraviolet rays were irradiated to define the alignment direction of the liquid crystal.
[0127]
In this panel, a tile-like pattern like the liquid crystal panel provided with the fine slits shown in FIG. 4 was not seen. Further, when halftone display was performed on the entire surface, no unevenness was observed.
[0128]
Similarly, as shown in FIG. 23, a fine bank-like structure is provided on the counter substrate instead of the substrate on the side of the TFT element, a transparent electrode is provided thereon, and the transparent electrode is flattened with an insulating material. A panel was made. The transparent electrode on the TFT substrate side was left in a rectangular shape without slits. The bank-like structure was arranged so as to protrude 4 microns from the transparent electrode on the opposite TFT substrate side. As the liquid crystal, a material obtained by mixing 0.3 wt% of a diacrylate monomer with a liquid crystal composition having a negative dielectric anisotropy was used.
[0129]
In this panel, as in the first and second embodiments, the alignment can be regulated by tilting the liquid crystal molecules in parallel with the bank in the vicinity of the bank without providing a fine slit. As a result, when halftone display was performed on the entire surface, a tile-like pattern generated in the liquid crystal panel provided with the fine slits shown in FIG. 4 was not seen. Further, when halftone display was performed on the entire surface, no unevenness was observed.
[0130]
Next, a fourth embodiment will be described.
[0131]
FIG. 24 is a view showing a liquid crystal panel according to a fourth embodiment of the second configuration of the present invention, and FIG. 24A is a plan view of a transparent electrode on the side facing the side with the TFT element, and FIG. FIG. 4 is a cross-sectional view of the liquid crystal panel taken along line L1-L2 in FIG.
[0132]
As shown in FIG. 24, a panel in which a bank-like structure was provided on a counter substrate was manufactured. As the liquid crystal, a material obtained by mixing 0.3 wt% of a diacrylate monomer with a liquid crystal composition having a negative dielectric anisotropy was used.
[0133]
After injecting the liquid crystal, ultraviolet rays were applied while applying a voltage between the substrates to define the alignment direction of the liquid crystal.
[0134]
In this panel, as in the first, second, and third examples, a tile-like pattern generated in the liquid crystal panel provided with the fine slits shown in FIG. 4 could not be seen without providing the fine slits. Further, when halftone display was performed on the entire surface, no unevenness was observed.
[0135]
Further, the liquid crystal panel of the fourth embodiment has an advantage that it is easy to manufacture as compared with the first, second and third embodiments, but the transmittance is low because the shape of the bank is large.
[0136]
(Supplementary note 1) Two substrates having electrodes with alignment films formed on the surface are sealed with the alignment film side facing each other, a gap is provided between the opposed substrates, and liquid crystal is sealed in the gap. A liquid crystal panel in which a plurality of pixels made of the electrodes are arranged on one of the substrates, and the liquid crystal panel is controlled by controlling a voltage applied between the pixel electrodes and the electrodes facing the pixel electrodes. In the manufacturing method of the liquid crystal display device that regulates the orientation of the liquid crystal molecules in the inside,
The liquid crystal panel is
Encapsulating a liquid crystal composition comprising a polymerizable monomer;
Irradiating light from a direction inclined with respect to the normal direction of the liquid crystal panel surface to polymerize the monomer;
A method for manufacturing a liquid crystal display device, comprising:
[0137]
(Supplementary Note 2) The step of polymerizing the monomer includes a first step of polymerizing the monomer by irradiating the light without applying a voltage between the electrodes.
A method for manufacturing a liquid crystal display device according to appendix 1.
[0138]
(Supplementary Note 3) The step of polymerizing the monomer includes a second step of irradiating light with a voltage applied between the electrodes after the first step.
A manufacturing method of the liquid crystal display device according to attachment 2.
[0139]
(Supplementary Note 4) In the display area of the liquid crystal panel, the light is irradiated after selecting an area to be irradiated with light.
The method for manufacturing a liquid crystal display device according to any one of appendices 1 to 3.
[0140]
(Additional remark 5) In the display area of the liquid crystal panel, a plurality of areas having different light irradiation directions are mixed.
The method for manufacturing a liquid crystal display device according to any one of appendices 1 to 4.
[0141]
(Appendix 6) The light is ultraviolet light.
The method for manufacturing a liquid crystal display device according to any one of appendices 1 to 5.
[0142]
(Appendix 7) The alignment film is a vertical alignment film.
The method for manufacturing a liquid crystal display device according to any one of appendices 1 to 6.
[0143]
(Supplementary note 8) The liquid crystal composition sealed in the liquid crystal panel has negative dielectric anisotropy, and the liquid crystal molecules are aligned substantially perpendicular to the substrate surface in the first step,
In the liquid crystal panel, a first polarizing plate is disposed on one side, and a second polarizing plate having a light absorption axis orthogonal to the first polarizing plate is disposed on the other side.
A method for manufacturing a liquid crystal display device according to appendix 7.
[0144]
(Appendix 9) The alignment film is a horizontal alignment film.
The method for manufacturing a liquid crystal display device according to any one of appendices 1 to 6.
[0145]
(Supplementary Note 10) The liquid crystal composition sealed in the liquid crystal panel has positive dielectric anisotropy, and the liquid crystal molecules are aligned substantially horizontally with respect to the substrate surface in the first step,
In the liquid crystal panel, a first polarizing plate is disposed on one side, and a second polarizing plate having a light absorption axis orthogonal to the first polarizing plate is disposed on the other side.
A method for manufacturing a liquid crystal display device according to appendix 9.
[0146]
(Appendix 11) Two substrates having electrodes with alignment films formed thereon are sealed with the alignment film side facing each other, with a gap provided between the opposing substrates, and a negative dielectric constant different from the gap. A liquid crystal panel in which a liquid crystal containing a monomer having a directionality and a polymerizable property is encapsulated, and a plurality of pixels composed of the substantially rectangular electrodes are arranged on one of the substrates; In a liquid crystal display device that regulates the orientation of liquid crystal molecules in the liquid crystal by controlling the voltage applied between both electrodes with the electrode facing this,
The liquid crystal is irradiated with light to polymerize the monomer,
The director of the liquid crystal molecules in the domain is oriented in a direction where the first tilt angle θ1 with respect to the pixel electrode is less than 90 °.
A liquid crystal display device characterized by the above.
[0147]
(Supplementary note 12) Each of the pixels is divided into domains cut by a plurality of line segments extending radially on the surface from a center point of the surface of the pixel electrode,
The director of the liquid crystal molecules in the domain is different in the azimuth angle φ on the surface between adjacent domains, and is oriented in a direction substantially centering on the center point of the surface of the pixel electrode,
The liquid crystal display device according to appendix 11, wherein a director of liquid crystal molecules in a boundary region adjacent to the boundary of the adjacent domains and a boundary region occupying the vicinity thereof is directed to a second tilt angle θ2 different from the first tilt angle θ1.
[0148]
(Supplementary note 13) The liquid crystal display device according to supplementary note 12, wherein the second tilt angle θ2 of the boundary region is approximately 90 °.
[0149]
(Supplementary Note 14) On the one substrate, the data bus lines and the gate bus lines arranged in a matrix form intersect substantially vertically, and have a substantially rectangular transparent pixel electrode between the two bus lines. 14. The liquid crystal display device according to appendix 12 or 13, wherein the boundary region is in a region corresponding to a cross that intersects the center point of the surface of the pixel electrode.
[0150]
(Supplementary Note 15) On the one substrate, the data bus lines and the gate bus lines arranged in a matrix form intersect substantially vertically, and have a substantially rectangular transparent pixel electrode between the two bus lines. 14. The liquid crystal display device according to appendix 12 or 13, wherein a boundary region is in a region corresponding to a cross that intersects a center point on the surface of the pixel electrode and a region in the vicinity of the long side of the pixel electrode.
[0151]
(Supplementary Note 16) On the one substrate, the data bus lines and the gate bus lines arranged in a matrix form intersect substantially vertically, and have a substantially rectangular transparent pixel electrode between both bus lines. 14. The liquid crystal display device according to appendix 12 or 13, wherein the boundary area is in an area corresponding to a square shape on the surface of the pixel electrode.
[0152]
(Supplementary Note 17) On the one substrate, the data bus lines and the gate bus lines arranged in a matrix form intersect substantially vertically, and have a substantially rectangular transparent pixel electrode between both bus lines. 14. The liquid crystal display device according to appendix 12 or 13, wherein a boundary region is a region corresponding to a square shape on the surface of the pixel electrode and is a region excluding the four corners of the pixel electrode.
[0153]
(Supplementary Note 18) On one of the substrates, the data bus lines and the gate bus lines arranged in a matrix form intersect substantially vertically, and have a substantially rectangular transparent pixel electrode between both bus lines. 14. The liquid crystal display device according to appendix 12 or 13, wherein the electrode has a groove running in a direction of a predetermined angle with respect to the bus line.
[0154]
(Supplementary note 19) The liquid crystal display device according to supplementary note 18, wherein the predetermined angle is 45 degrees.
[0155]
(Supplementary note 20) In any one of supplementary notes 11 to 19, wherein a spacer for maintaining a gap between two substrates is only on the TFT connected to the data bus line, the gate bus line, and the transparent electrode. The liquid crystal display device described.
[0156]
(Supplementary Note 21) The monomer is polymerized by irradiating only the domain while applying a voltage between the electrodes, and then exposing the entire liquid crystal panel without applying a voltage between the electrodes. 20. The liquid crystal display device according to any one of appendices 11 to 19, which is polymerized.
[0157]
(Appendix 22) The monomer is polymerized by irradiating only the domain while applying a voltage between the electrodes, and then exposing the boundary region without applying a voltage between the electrodes. 20. The liquid crystal display device according to any one of appendices 11 to 19, which is polymerized.
[0158]
(Supplementary Note 23) The monomer is polymerized by irradiating light only to the boundary region without applying a voltage between the electrodes, and then exposing only the domain by applying a voltage between the electrodes. 20. The liquid crystal display device according to any one of appendices 11 to 19.
[0159]
(Supplementary note 24) The liquid crystal display device according to any one of supplementary notes 11 to 23, wherein the light is ultraviolet light.
[0160]
(Appendix 25) Two substrates having electrodes with alignment films formed thereon are sealed with the alignment film side facing each other, with a gap provided between the opposing substrates, and having a negative dielectric constant in the gap. And a liquid crystal panel in which a plurality of pixels made of substantially rectangular electrodes are arranged on one of the substrates, and both the pixel electrodes and the electrodes opposed thereto are provided on one of the substrates. In a liquid crystal display device that regulates the orientation of liquid crystal molecules in the liquid crystal by controlling the voltage applied between the electrodes,
The liquid crystal panel is
A liquid crystal composition containing a polymerizable monomer is enclosed, and the monomer is polymerized by irradiating light with a voltage applied between the electrodes.
A plurality of bank-like structures made of an insulator aligned substantially in parallel on the surface of the pixel electrode;
The liquid crystal is divided into domains cut by a plurality of line segments extending radially from the center point of the surface of the pixel electrode,
The bank-like structure is different in the alignment direction of the bank-like structure for each domain,
When a voltage is applied between the electrodes, the liquid crystal molecules in the liquid crystal corresponding to the pixels are inclined in a direction substantially parallel to the bank-like structure.
A liquid crystal display device characterized by the above.
[0161]
(Appendix 26) Two substrates having electrodes with alignment films formed thereon are sealed with the alignment film side facing each other, with a gap provided between the opposing substrates, and a negative dielectric constant in the gap. And a liquid crystal panel in which a plurality of pixels made of substantially rectangular electrodes are arranged on one of the substrates, and both the pixel electrodes and the electrodes opposed thereto are provided on one of the substrates. In a liquid crystal display device that regulates the orientation of liquid crystal molecules in the liquid crystal by controlling the voltage applied between the electrodes,
The liquid crystal panel is
A liquid crystal composition containing a polymerizable monomer is enclosed, and the monomer is polymerized by irradiating light with a voltage applied between the electrodes.
Provided with a plurality of bank-like irregularities aligned substantially parallel on the surface of the pixel electrode,
The liquid crystal is divided into domains cut by a plurality of line segments extending radially from the center point of the surface of the pixel electrode,
The bank-like irregularities are different in the alignment direction of the bank-like irregularities for each domain,
When a voltage is applied between the electrodes, the liquid crystal molecules in the liquid crystal corresponding to the pixels are tilted in a direction substantially parallel to the bank-like unevenness,
A liquid crystal display device characterized by the above.
[0162]
(Supplementary Note 27) Two substrates having electrodes with alignment films formed thereon are sealed with the alignment film side facing each other, with a gap provided between the opposing substrates, and a negative dielectric constant different in the gap. And a liquid crystal panel in which a plurality of pixels made of substantially rectangular electrodes are arranged on one of the substrates, and both the pixel electrodes and the electrodes opposed thereto are provided on one of the substrates. In a liquid crystal display device that regulates the orientation of liquid crystal molecules in the liquid crystal by controlling the voltage applied between the electrodes,
The liquid crystal panel is
A liquid crystal composition containing a polymerizable monomer is enclosed, and the monomer is polymerized by irradiating light with a voltage applied between the electrodes.
On the substrate on the pixel electrode side, a plurality of bank-like structures aligned substantially in parallel are formed to form a transparent electrode, and the transparent electrode is provided with bank-like irregularities,
The liquid crystal is divided into domains cut by a plurality of line segments extending radially from the center point of the surface of the pixel electrode,
The bank-like irregularities are different in the alignment direction of the bank-like irregularities for each domain,
When a voltage is applied between the electrodes, the liquid crystal molecules corresponding to the pixels are tilted in a direction substantially parallel to the bank-like irregularities.
A liquid crystal display device characterized by the above.
[0163]
(Supplementary note 28) An insulating layer is provided on the transparent electrode provided with the bank-like irregularities, and when the voltage is applied between the two electrodes, the insulation of the lines of electric force that penetrate the insulating layer and enter the liquid crystal The angle between the layers is acute,
The liquid crystal display device according to appendix 27.
[0164]
(Supplementary Note 29) There are four alignment directions of the bank-like structure or the bank-like unevenness corresponding to the pixel.
29. The liquid crystal display device according to any one of appendices 25 to 28.
[0165]
(Additional remark 30) The alignment direction of the bank-like structure is a 45 degree direction with respect to the data bus line.
29. The liquid crystal display device according to any one of appendices 25 to 28.
[0166]
(Additional remark 31) The bank width of the bank-like structure is 1 to 10 microns, and the gap between adjacent bank-like structures is 1 to 10 microns.
29. The liquid crystal display device according to any one of appendices 25 to 28.
[0167]
(Appendix 32) Two substrates having electrodes with alignment films formed thereon are sealed with the alignment film side facing each other, with a gap provided between the opposing substrates, and having a negative dielectric constant in the gap. And a liquid crystal panel in which a plurality of pixels made of substantially rectangular electrodes are arranged on one of the substrates, and both the pixel electrodes and the electrodes opposed thereto are provided on one of the substrates. In a liquid crystal display device that regulates the orientation of liquid crystal molecules in the liquid crystal by controlling the voltage applied between the electrodes,
The liquid crystal panel is
A liquid crystal composition containing a polymerizable monomer is enclosed, and the monomer is polymerized by irradiating light with a voltage applied between the electrodes.
A bank provided on the substrate side facing the pixel electrode;
A liquid crystal display device characterized by realizing quadrant alignment.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram of first control means for horizontal alignment.
FIG. 2 is an explanatory diagram of a second control means for horizontal alignment.
FIGS. 3A and 3B are explanatory diagrams of a vertically aligned MVA mode, in which FIG. 3A shows a voltage off state between electrodes, and FIG. 3B shows a voltage on state between electrodes;
FIG. 4 is a diagram showing a pixel electrode structure having a fine slit.
FIG. 5 is a diagram showing a method according to the present invention for regulating the alignment of liquid crystal molecules using an electrode with a vertical alignment film, wherein (A) shows the state of the liquid crystal molecules when no voltage is applied to the liquid crystal layer. (B) is a figure which shows the state of a liquid crystal molecule when a voltage is applied to a liquid-crystal layer.
FIG. 6 is a diagram showing a method according to the present invention for regulating the alignment of liquid crystal molecules using an electrode provided with a horizontal alignment film, wherein (A) shows the state of the liquid crystal molecules when no voltage is applied to the liquid crystal layer. (B) is a figure which shows the state of a liquid crystal molecule when a voltage is applied to a liquid-crystal layer.
FIG. 7 is a diagram illustrating a relationship between a light irradiation angle with respect to a normal line of a liquid crystal panel surface and a tilt angle of liquid crystal molecules.
FIG. 8 is a diagram showing another method according to the present invention for regulating the alignment of liquid crystal molecules.
FIG. 9 is a diagram illustrating a method of manufacturing a multi-domain liquid crystal panel.
FIG. 10 is a plan view showing the structure of one substrate of a liquid crystal panel according to the present invention.
FIGS. 11A and 11B are explanatory diagrams of a method for realizing a liquid crystal panel having two domains. FIG. 11I shows a first step, and FIG. 11II shows a second step.
FIG. 12 is an explanatory view of a method for realizing a liquid crystal panel having four domains, (I) shows the first step, (II) shows the second step, and (III) shows the third step. (IV) is a figure which shows a 4th process.
FIG. 13 is a diagram illustrating a state of liquid crystal molecules in a portion corresponding to one pixel of a liquid crystal panel divided into four domains.
FIG. 14 is a diagram showing the orientation of liquid crystal molecules on each side around a pixel electrode.
FIG. 15 is a diagram showing a first embodiment of a liquid crystal panel of the present invention.
FIG. 16 is a diagram showing a second embodiment of the liquid crystal panel of the present invention.
FIG. 17 is a diagram showing a third embodiment of the liquid crystal panel of the present invention.
FIG. 18 is a diagram showing a fourth embodiment of the liquid crystal panel of the present invention.
FIG. 19 is a diagram showing a fifth embodiment of the liquid crystal panel of the present invention.
FIG. 20 is a diagram showing a sixth embodiment of the liquid crystal panel of the present invention.
FIGS. 21A and 21B are views showing a liquid crystal panel according to a first embodiment of the second configuration of the present invention, in which FIG. 21A is a plan view of a transparent electrode on a side where a TFT element is present, and FIG. 2 is a cross-sectional view of the liquid crystal panel taken along line L1-L2.
22A and 22B are diagrams showing a liquid crystal panel according to a second embodiment of the second configuration of the present invention, in which FIG. 22A is a plan view of a transparent electrode on a side where a TFT element is present, and FIG. 2 is a cross-sectional view of the liquid crystal panel taken along line L1-L2.
23A and 23B are diagrams showing a liquid crystal panel according to a third embodiment of the second configuration of the present invention, in which FIG. 23A is a plan view of a transparent electrode on a side where a TFT element is present, and FIG. 2 is a cross-sectional view of the liquid crystal panel taken along line L1-L2.
FIG. 24 is a view showing a liquid crystal panel of a fourth embodiment according to the second configuration of the present invention, and FIG. 24 (A) is a plan view of a transparent electrode on the side facing the side with the TFT element, and FIG. ) Is a cross-sectional view of the liquid crystal panel taken along line L1-L2 in FIG.
[Explanation of symbols]
1, 1 '... Transparent electrode
2 ... Liquid crystal
3, 4 ... Glass substrate
5 ... bank
6, 6 '... Alignment film

Claims (5)

Two substrates having an electrode with an alignment film formed on the surface are sealed with the alignment film side facing each other, a gap is provided between the opposing substrates, and the gap has a negative dielectric anisotropy. A liquid crystal panel in which a plurality of pixels composed of substantially rectangular electrodes are aligned is provided on one of the substrates, and a pixel electrode which is an electrode forming the pixel and an electrode opposed thereto In a liquid crystal display device that regulates the orientation of liquid crystal molecules in the liquid crystal by controlling the voltage applied between both electrodes,
The liquid crystal panel is
A liquid crystal composition containing a polymerizable monomer is enclosed, and the monomer is polymerized by irradiating light with a voltage applied between the electrodes.
A plurality of bank-like structures aligned substantially parallel on the surface of the pixel electrode;
The liquid crystal is divided into domains cut by a plurality of line segments extending radially from the center point of the surface of the pixel electrode,
The bank-like structure is different in the alignment direction of the bank-like structure for each domain,
When a voltage is applied between the electrodes, the liquid crystal molecules in the liquid crystal corresponding to the pixels are inclined in a direction substantially parallel to the bank-like structure,
The bank-like structure is a bank-like structure provided on the transparent electrode itself by forming a transparent electrode on a plurality of bank-like structures arranged in parallel on the substrate on the pixel electrode side. The unevenness of
An angle formed between the insulating layer on the transparent electrode provided with the bank-like irregularities and the line of electric force that penetrates the insulating layer and enters the liquid crystal when a voltage is applied between the electrodes. liquid crystal display device you characterized in that but is an acute angle. Two substrates having an electrode with an alignment film formed on the surface are sealed with the alignment film side facing each other, a gap is provided between the opposing substrates, and the gap has a negative dielectric anisotropy. A liquid crystal panel in which a plurality of pixels composed of substantially rectangular electrodes are aligned is provided on one of the substrates, and a pixel electrode which is an electrode forming the pixel and an electrode opposed thereto In a liquid crystal display device that regulates the orientation of liquid crystal molecules in the liquid crystal by controlling the voltage applied between both electrodes,
The liquid crystal panel is
A liquid crystal composition containing a polymerizable monomer is enclosed, and the monomer is polymerized by irradiating light with a voltage applied between the electrodes.
A plurality of bank-like structures aligned substantially parallel on the surface of the pixel electrode;
The liquid crystal is divided into domains cut by a plurality of line segments extending radially from the center point of the surface of the pixel electrode,
The bank-like structure is different in the alignment direction of the bank-like structure for each domain,
When a voltage is applied between the electrodes, the liquid crystal molecules in the liquid crystal corresponding to the pixels are inclined in a direction substantially parallel to the bank-like structure,
Liquid crystal display device wherein the bank-like structure you characterized by being made of an insulating material. The liquid crystal display device according to claim 1 or 2, characterized in that the alignment direction of the bank-like structure corresponding to the pixel is four directions. 3. The liquid crystal display device according to claim 1, wherein an alignment direction of the bank-like structures is a 45 degree direction with respect to a data bus line provided on the substrate on the pixel electrode side. 3. The liquid crystal according to claim 1, wherein the bank-like structure has a bank width of 1 to 10 microns, and a gap between adjacent bank-like structures is 1 to 10 microns. Display device.

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