JP3545086B2 - Liquid crystal display - Google Patents

Description

[0001]
[Industrial applications]
The present invention relates to a configuration of a liquid crystal display device that performs passive driving or active driving for displaying characters, symbols, and other images, and particularly to a liquid crystal display device related to a technique for improving the viewing angle characteristics.
[0002]
[Prior art]
In general, a liquid crystal display device is provided with a liquid crystal alignment layer made of polyimide having a uniform thickness on a glass substrate having a pair of display pixel electrodes, and bonding the glass substrates together so as to maintain a constant gap. A liquid crystal layer is provided by enclosing the material.
[0003]
Hereinafter, a structure of a liquid crystal display device that performs general passive driving will be described with reference to FIG. FIG. 5 is a sectional view showing a conventional passively driven liquid crystal display device.
[0004]
A first display pixel electrode 52a and a second display pixel electrode 52b are provided on the first glass substrate 51a and the second glass substrate 51b, respectively.
[0005]
Further, on the first display pixel electrode 52a and the second display pixel electrode 52b, a first liquid crystal alignment layer 53a and a second liquid crystal alignment layer rubbed using a cotton cloth in a predetermined direction, respectively. 53b is provided.
[0006]
Further, the first glass substrate 51a and the second glass substrate 51b are bonded to each other by using the sealing material 54 so as to face each other, and the liquid crystal layer 55 is provided in the gap therebetween.
[0007]
Next, the planar pattern shape of the liquid crystal display device having the above configuration will be described. FIG. 6 is a plan view showing a general passive drive liquid crystal display device.
[0008]
The liquid crystal display device applies a driving voltage to the first display pixel electrode 52a provided on the first glass substrate 51a and the second display pixel electrode 52b provided on the second glass substrate 51b. Thus, an electric field is applied to the liquid crystal layer sealed in the gap to perform liquid crystal display.
[0009]
Therefore, each of the hatched portions, which are areas where the first display pixel electrode 52a and the second display pixel electrode 52b overlap in a planar manner, becomes the display pixel 57 that actually lights up and performs display.
[0010]
Next, a method for manufacturing the liquid crystal display device configured as described above will be briefly described with reference to FIGS.
[0011]
First, a first glass substrate 51a and a second glass substrate 51b, each having a transparent electrode film formed on one entire surface by a sputtering method or a vacuum evaporation method, are subjected to an exposure process using a photomask having a predetermined pattern, a development process, By an etching process, a predetermined electrode pattern, that is, a first display pixel electrode 52a and a second display pixel electrode 52b are formed.
[0012]
Thereafter, a polyimide varnish is formed on the upper surfaces of the first display pixel electrode 52a and the second display pixel electrode 52b with a uniform film thickness by flexographic printing.
[0013]
Thereafter, a baking treatment of the polyimide varnish is performed to form an alignment film. Next, a rubbing treatment of rubbing the surface in a predetermined direction with a cotton cloth in a predetermined direction is performed to form a first liquid crystal alignment layer 53a and a second liquid crystal alignment layer 53b.
[0014]
Thereafter, the first glass substrate 51a and the second glass substrate 51b are bonded to each other with a sealing material 54 so as to maintain a predetermined gap, and a liquid crystal material is injected into the gap by a vacuum injection method to form a liquid crystal layer 55. Thus, a liquid crystal display device is obtained.
[0015]
Next, a liquid crystal display device having a structure different from that described above will be described with reference to FIG. FIG. 7 is a cross-sectional view showing a conventional passively driven liquid crystal display device in which an insulating film layer is provided between a liquid crystal alignment layer and a display pixel electrode.
[0016]
As shown in FIG. 7, an insulating film layer 56 provided between the second display pixel electrode 52b and the second liquid crystal alignment layer 53b is provided to prevent a defect generally called a vertical short circuit. .
[0017]
The vertical short-circuit defect is caused in the liquid crystal display device manufacturing process, especially in the process of bonding glass substrates to each other, by causing conductive fine foreign particles such as dust and dust generated from the atmosphere or from manufacturing equipment to be trapped between the glass substrates. When the conductive minute foreign matter penetrates the liquid crystal alignment layer, the first display pixel electrode 52a and the second display pixel electrode 52b are short-circuit defects generated through the conductive minute foreign matter.
[0018]
Accordingly, an insulating film layer 56 made of a hard inorganic insulating film such as silicon oxide (SiO2) or a hard insulating film obtained by firing organic silicon is provided between the liquid crystal alignment layer and the display pixel electrode.
[0019]
By providing the insulating film layer 56, even if conductive minute foreign matter is interposed between the glass substrates, the insulating film layer 56 is not pierced.
[0020]
As a result, the first display pixel electrode 52a and the second display pixel electrode 52b are not short-circuited, and the occurrence of short-circuiting in the vertical direction can be prevented.
[0021]
As a method of manufacturing the insulating film layer 56, an organic silicon varnish is formed to a uniform thickness on the second display pixel electrode 52b by flexographic printing, and then fired to form the insulating film layer 56.
[0022]
Further, except for the process of forming a polyimide varnish to a uniform film thickness by a flexographic printing method on the insulating film layer 56 and then performing a baking process to form the liquid crystal alignment layer 53, the liquid crystal described with reference to FIG. Since the structure is the same as that of the display device, detailed description is omitted.
[0023]
[Problems to be solved by the invention]
However, in the prior art liquid crystal display device having the configuration shown in FIGS. 5 and 7, the first liquid crystal alignment layer 53a and the first liquid crystal alignment layer 53a on the first display pixel electrode 52a and the second display pixel electrode 52b. The liquid crystal alignment layer 53b and the insulating film layer 56 have a uniform thickness.
[0024]
For this reason, the threshold voltage of the liquid crystal in the display screen becomes the same for each display pixel, and each display pixel 57 shows uniform luminance according to the drive voltage.
[0025]
The definition of the threshold voltage is shown using the graph of FIG. 8 showing the voltage and the transmittance. The threshold voltage means a changing point in a change in transmittance when a voltage is applied to the liquid crystal display device by scanning, and means how many volts the liquid crystal display device turns on.
[0026]
Here, when the amount of transmitted light that changes between light and dark is assumed to be 100%, the voltage at which the amount of transmitted light changes by 10% and reaches 90% is set as the threshold voltage.
[0027]
When display is performed by applying a drive signal to a conventional liquid crystal display device having the same threshold voltage in a screen, uniform display can be obtained.
[0028]
However, in such a conventional liquid crystal display device, the viewing angle dependence of the contrast occurs according to the orientation direction of the liquid crystal layer, and depending on the viewing direction, the display quality is remarkably deteriorated due to gradation inversion or a sharp decrease in contrast. .
[0029]
When the size of a display screen such as a personal computer display is increased, it is particularly desired to improve such a viewing angle dependency.
[0030]
In the above description of the conventional example, a passive drive liquid crystal display device has been described. However, the same drawbacks as described above occur in an active drive liquid crystal display device having an active element in each display pixel portion.
[0031]
An object of the present invention is to solve the above-mentioned problems and to provide a structure of a liquid crystal display device having a wide viewing angle.
[0032]
[Means for Solving the Problems]
In order to achieve the above object, the liquid crystal display device of the present invention employs the following means.
[0033]
The liquid crystal display device according to the present invention is characterized in that the thickness of the liquid crystal alignment layer on the display pixel electrode on both the first glass substrate and the second glass substrate or on at least one of the glass substrates is reduced. A feature is that a plurality of film thickness regions are provided for each pixel, or a film thickness gradient is provided for each display pixel in the film thickness of the liquid crystal alignment layer.
[0034]
The liquid crystal display device of the present invention provides a display on the thickness of the insulating film layer on the display pixel electrode on both the first glass substrate and the second glass substrate, or on at least one of the glass substrates. A feature is that a plurality of film thickness regions are provided for each pixel, or a film thickness gradient is provided for each display pixel in the thickness of the insulating film layer.
[0035]
[Action]
The reason why the threshold voltage can be changed from the above-described structure will be described with reference to FIG. The graph of FIG. 2 shows a change in the threshold voltage of the liquid crystal display device when the thickness of the liquid crystal alignment layer is changed.
[0036]
Since the liquid crystal alignment layer is an insulating material, the voltage applied between the first display pixel electrode and the second display pixel electrode depends on the electric capacity ratio between the dielectric alignment film layer and the liquid crystal layer. It is divided.
[0037]
As the thickness of the liquid crystal alignment layer increases, the voltage applied to the liquid crystal layer decreases. Therefore, as shown in the graph of FIG. 2, the threshold voltage increases as the thickness of the liquid crystal alignment layer increases.
[0038]
The gradient of the curve in the graph of FIG. 2 changes depending on the dielectric constant between the liquid crystal alignment layer and the liquid crystal layer.
[0039]
Further, since the insulating film layer used for countermeasures against upper and lower shorts described with reference to FIG. 7 also serves as a dielectric, the threshold voltage changes with a change in the film thickness similarly to the case of the liquid crystal alignment layer.
[0040]
The present invention utilizes the change in the thickness of the liquid crystal alignment layer on the display pixel obtained from such knowledge, and the change in the threshold voltage due to the change in the thickness of the insulating film layer as a countermeasure against short-circuiting failure.
[0041]
By providing a plurality of film thickness regions or film thickness gradients in the liquid crystal alignment layer in each display pixel according to the present invention, a plurality of threshold voltage regions due to differences in the thickness of the liquid crystal alignment layer in each display pixel, Alternatively, a threshold voltage gradient can be obtained.
[0042]
For this reason, when a signal of a constant voltage is applied, a voltage according to the thickness of each liquid crystal alignment layer is applied to the liquid crystal layer for each display pixel, and the rise of the liquid crystal molecules according to the thickness of the liquid crystal alignment layer. Be better.
[0043]
In addition, since a region in which one display pixel is driven by different voltages is substantially mixed, it is possible to synthesize a display whose contrast is adjusted by a plurality of voltages, that is, to improve a viewing angle characteristic.
[0044]
Further, when an insulating film layer for short-circuiting in the vertical direction is provided below the liquid crystal alignment layer, a plurality of thickness regions or thickness gradients are provided in the insulating film layer in each display pixel.
[0045]
Thus, as in the case of the liquid crystal alignment layer, a plurality of threshold voltage regions or threshold voltage gradients can be obtained, and the viewing angle characteristics can be improved.
[0046]
【Example】
Hereinafter, embodiments of the present invention will be described with reference to the drawings. A sectional structure of the liquid crystal display device according to the embodiment of the present invention is shown in a sectional view of FIG. FIG. 6 is a plan view showing a planar pattern shape of the liquid crystal display device. In the following description, a passively driven liquid crystal display device will be described as an example.
[0047]
As shown in FIG. 1, a first display pixel electrode 52a made of indium tin oxide (ITO) as a transparent electrode film and a second display are provided on a first glass substrate 51a and a second glass substrate 51b. A pixel electrode 52b is provided.
[0048]
Further, a first liquid crystal alignment layer 53a and a second liquid crystal alignment layer 53b made of polyimide are provided on the upper surfaces of the first display pixel electrode 52a and the second display pixel electrode 52b, respectively.
[0049]
In particular, in the second liquid crystal alignment layer 53b, a 30 nm-thickness region and a 130 nm-thickness region are provided for each display pixel 57 at an area ratio of about 50%. The illustration of the liquid crystal alignment layer is omitted in the plan view of FIG.
[0050]
Further, the first glass substrate 51a and the second glass substrate 51b are overlapped with a sealing material 54 made of an epoxy adhesive so as to maintain a uniform gap, and a liquid crystal material is injected into the gap to form a liquid crystal layer 55.
[0051]
A region where the first display pixel electrode 52a and the second display pixel electrode 52b overlap, that is, a film thickness of 30 nm and a film thickness of 130 nm for each display pixel 57 unit shown in FIG. Are provided.
[0052]
A manufacturing method for forming the structure of the liquid crystal display device configured as described above will be described below.
[0053]
A first glass substrate 51a and a second glass substrate 51a on which a first display pixel electrode 52a and a second display pixel electrode 52b of a predetermined pattern obtained by performing a photolithography process and an etching process, respectively, are provided. A polyimide varnish is formed on the entire display area of the glass substrate 51b by flexographic printing.
[0054]
Then, only the second glass substrate 51b is pre-baked, and the polyimide varnish is baked.
[0055]
Thereafter, a photoresist is formed on the entire surface of the polyimide varnish by a spin coating method, and the photoresist is prebaked.
[0056]
Thereafter, using a photomask that shields a half area of each display pixel 57, an exposure process and a development process are performed to pattern the photoresist.
[0057]
Next, the polyimide varnish is etched using the patterned photoresist as an etching mask. The etching of the polyimide varnish is performed using hydrazine as an etchant. Thereafter, the photoresist is stripped.
[0058]
Here, the etching time is adjusted so that 30 nm remains from the etching completion time of the entire film thickness. As a result, a second liquid crystal alignment layer 53b having a difference in film thickness can be formed in each display pixel 57.
[0059]
Thereafter, a baking process is performed at a temperature of 200 ° C. for one hour, so that the half region of each display pixel 57 finally has a thickness of 130 nm, and the second half of the etched region has a thickness of 30 nm in the second half region. Can be obtained.
[0060]
Further, the first glass substrate 51a is formed by forming a polyimide varnish by flexographic printing and then performing a baking treatment at a temperature of 200 ° C. for 1 hour to form a first liquid crystal alignment layer 53a.
[0061]
Thereafter, the surfaces of the first liquid crystal alignment layer 53a and the second liquid crystal alignment layer 53b on the first glass substrate 51a and the second glass substrate 51b are rubbed in a predetermined direction with a roll of cotton cloth, and The first liquid crystal alignment layer 53a and the second liquid crystal alignment layer 53b that have been subjected to the alignment treatment are obtained.
[0062]
Thereafter, the first glass substrate 51a and the second glass substrate 51b are bonded together with a sealing material 54 so as to maintain a gap of 5 μm, and a liquid crystal material is injected into the gap by a vacuum injection method to form a liquid crystal layer 55. To obtain a liquid crystal display device.
[0063]
FIG. 2 is a graph showing the relationship between the thickness of the polyimide varnish constituting the liquid crystal alignment layer used in the present invention and the threshold voltage of the liquid crystal display device due to the change in the thickness of the liquid crystal alignment layer.
[0064]
As shown in the graph of FIG. 2, the voltage applied to the liquid crystal layer is divided and changed based on the ratio of the capacitance of the liquid crystal alignment layer of the dielectric material to the capacitance of the liquid crystal layer. It is rising according to the increase.
[0065]
Therefore, in the liquid crystal display device according to the embodiment of the present invention, the threshold voltage of the liquid crystal alignment layer region having a thickness of 30 nm and the liquid crystal alignment layer region serving as an insulating layer having a thickness of 130 nm differ by 0.12 V. Has occurred.
[0066]
Therefore, when the liquid crystal display device of the present invention is driven, one display pixel is driven by two types of driving voltages, and the viewing angle characteristics obtained by combining the viewing angle characteristics by the respective driving voltages are shown. Thereby, the liquid crystal display device can realize a wide viewing angle display.
[0067]
FIG. 3 is a graph showing the contrast-viewing angle characteristics of the embodiment of the present invention and the conventional example in comparison.
[0068]
An area having a contrast of 1 or less indicates a viewing angle at which the display is grayscale-inverted. As is apparent from FIG. 3, the viewing angle is improved by about 10 degrees with respect to the inversion as compared with the conventional technique.
[0069]
In the liquid crystal display device according to the embodiment of the present invention, the thickness of the liquid crystal alignment layer is changed by photolithography and etching. It is possible to form the layer by changing the thickness of the layer.
[0070]
Further, in the above description of the embodiment, an example in which the film thickness of the second liquid crystal alignment layer 53b on the second glass substrate 51b is changed by two kinds of film thickness is described. The thickness of the first liquid crystal alignment layer 53a may be changed so as to be a plurality of types of thickness.
[0071]
Further, the film thickness of the first liquid crystal alignment layer 53a on the first glass substrate 51a and the film thickness of the second liquid crystal alignment layer 53b on the second glass substrate 51b are changed so as to be a plurality of types. You may.
[0072]
Furthermore, in the description of the embodiments of the present invention, the first glass substrate and the second glass substrate are shown with a passive liquid crystal display device in which display pixel electrodes are provided. The present invention can be applied to an active drive liquid crystal display device provided with an active element such as a TFT (TFT) or a thin film diode (TFD).
[0073]
An active driving liquid crystal display device having TFT or TFD active elements on a glass substrate has the same effect as described above, and can display a wide viewing angle characteristic.
[0074]
Next, the structure of a liquid crystal display device according to a second embodiment of the present invention will be described with reference to FIG. FIG. 4 is a sectional view showing a liquid crystal display device according to a second embodiment of the present invention.
[0075]
As shown in FIG. 4, a first display pixel electrode 52a and a second display pixel electrode 52b made of ITO as transparent electrodes are formed on the upper surfaces of the first glass substrate 51a and the second glass substrate 51b. Is provided.
[0076]
On the first display pixel electrode 52a on the first glass substrate 51a, a first liquid crystal alignment layer 53a made of polyimide is provided.
[0077]
Further, on the second display pixel electrode 52b on the second glass substrate 51b, an insulating film layer 46 having two types of film thickness regions of 70 nm and 170 nm is provided for each display pixel 57. The insulating film layer 46 is made of an organic silicon-based insulating film.
[0078]
Further, a second liquid crystal alignment layer 53b made of a polyimide film is provided on the insulating film layer 46.
[0079]
This insulating film layer 46 causes a short between the first display pixel electrode 52a and the second display pixel electrode 52b due to conductive minute foreign matter such as a metal which may be mixed in a manufacturing process of the liquid crystal display device. That is, it is formed for the purpose of preventing short-circuiting between upper and lower portions.
[0080]
Further, a first display pixel electrode 52a and a first liquid crystal alignment layer 53a are provided on the first glass substrate 51a.
[0081]
Then, the first glass substrate 51a and the second glass substrate 51b are overlapped with each other by a sealing material 54 made of an epoxy adhesive so as to maintain a uniform gap, and a liquid crystal material is sealed in the gap to form a liquid crystal. A layer 55 is provided.
[0082]
A manufacturing method for forming the structure of the liquid crystal display device configured as described above will be described below.
[0083]
By performing photolithography and etching, the first display pixel electrode 52a and the second display pixel electrode 52b having a predetermined pattern are connected to the first glass substrate 51a and the second glass substrate 51b. Each is provided.
[0084]
Thereafter, an organic silicon-based material is formed on the entire surface of the first display pixel electrode 52a on the second glass substrate 51a by flexographic printing, and a temporary drying process is performed.
[0085]
Thereafter, using a printing plate capable of printing only in a half area of each display pixel 57, an organic silicon-based material is further formed on the temporarily dried organic silicon-based material by a printing method.
[0086]
Then, it is baked at a temperature of 250 ° C. for 2 hours. Thus, the insulating film layer 46 having two types of film thicknesses of 70 nm and 170 nm is formed for each display pixel 57.
[0087]
Thereafter, a polyimide varnish is formed as a liquid crystal alignment layer material on the upper surface of the insulating film layer 46 by a printing method, and baked at a temperature of 200 ° C. to form a second liquid crystal alignment layer 53b.
[0088]
Further, a polyimide varnish is formed on the upper surface of the first display pixel electrode 52a of the first glass substrate 51a by a flexographic printing method, and then a baking treatment is performed at a temperature of 200 ° C. As a result, a first liquid crystal alignment layer 53a is formed.
[0089]
Thereafter, the first liquid crystal alignment layer 53a and the second liquid crystal alignment layer 53b on the first glass substrate 51a and the second glass substrate 51b are subjected to rotational rubbing in a predetermined direction by a roll of cotton cloth, and the alignment is performed. The processed first liquid crystal alignment layer 53a and second liquid crystal alignment layer 53b are obtained.
[0090]
Thereafter, the first glass substrate 51a and the second glass substrate 51b are arranged so as to face each other so as to maintain a gap of 5 μm, and are bonded to each other with the sealing material.
[0091]
After that, a liquid crystal material is injected into a gap between the first glass substrate 51a and the second glass substrate 51b by a vacuum injection method to form a liquid crystal layer 55, whereby a liquid crystal display device can be obtained.
[0092]
In the liquid crystal display device according to the embodiment of the present invention, a difference in threshold voltage of 0.12 V occurs between the region of the insulating film layer 46 having a thickness of 70 nm and the region of the insulating film layer 46 having a thickness of 170 nm.
[0093]
Therefore, when the liquid crystal display device of the present invention is driven, one display pixel is driven by two types of driving voltages, and the viewing angle characteristics obtained by combining the viewing angle characteristics by the respective driving voltages are shown. Thereby, a liquid crystal display device having a wide viewing angle display can be realized.
[0094]
Further, in the embodiment described with reference to FIG. 4, the thickness of the insulating film layer 46 provided between the second display pixel electrode 52b of the second glass substrate 51b and the second liquid crystal alignment layer 53b. Was changed with two types of film thickness.
[0095]
However, an insulating film layer is provided between the first display pixel electrode 52a of the first glass substrate 51a and the first liquid crystal alignment layer 53a, and the thickness of the insulating film layer is reduced to a plurality of types. It may be changed so that
[0096]
Further, an insulating film layer is provided between the first display pixel electrode 52a of the first glass substrate 51a and the first liquid crystal alignment layer 53a, and the second display pixel electrode of the second glass substrate 51b is further provided. An insulating film layer may be provided between the electrode 52b and the second liquid crystal alignment layer 53b.
[0097]
As described above, the thicknesses of the insulating film layers of both the first glass substrate 51a and the second glass substrate 51b may be changed so as to have a plurality of types of film thicknesses.
[0098]
Further, in the embodiment described with reference to FIG. 4, the passive type liquid crystal display device is shown, but a thin film transistor (TFT) or a thin film diode (TFT) is provided for each display pixel unit of the first glass substrate 51a or the second glass substrate 51b. The present invention can also be applied to an active drive liquid crystal display device provided with an active element such as TFD).
[0099]
An active driving liquid crystal display device having TFT or TFD active elements on a glass substrate has the same effect as described above, and can display a wide viewing angle characteristic.
[0100]
Further, in the embodiment described with reference to FIG. 4, an example has been described in which the thickness of the insulating film layer 46 for preventing a vertical short is changed in each display pixel.
[0101]
However, a display pixel electrode is provided on a glass substrate, a color filter of dyed gelatin or a color filter in which a pigment is dispersed in a synthetic resin is provided on the display pixel electrode, and a flattening color filter is further provided on the color filter. In a passive or active drive color liquid crystal display device with a substrate provided with a synthetic resin layer having a role, the synthetic resin layer on the color filter is applied as an insulating film layer, and the thickness of the insulating film layer is changed. Also, the effect that the display of the wide viewing angle characteristic similar to the above description can be obtained is obtained.
[0102]
Further, in the embodiment described with reference to FIGS. 1 and 4, the thickness difference between the second liquid crystal alignment layer and the insulating film layer on the second glass substrate is two, but the thickness difference is three. Even with the above, the effect that the display with the wide viewing angle characteristics similar to the above description can be obtained is obtained.
[0103]
Furthermore, when the type of the thickness region having the thickness difference between the liquid crystal alignment layer and the insulating film layer is continuously and infinitely increased, that is, a film thickness gradient is formed in the liquid crystal alignment layer or the insulating film layer for each display pixel. Even in this case, the same effect as described above can be obtained.
[0104]
This film thickness gradient can be formed, for example, by flexographic printing using a flexographic printing plate whose plate thickness is continuously changed for each display pixel.
[0105]
This film thickness gradient can also be formed by patterning the liquid crystal alignment layer or the insulating film layer using a photomask that continuously changes the exposure amount for each display pixel unit in the photolithography method. .
[0106]
【The invention's effect】
As described above, according to the liquid crystal display device of the present invention, by forming a plurality of thickness regions in the liquid crystal alignment layer or the insulating film layer for each display pixel, or alternatively, for each display pixel A film thickness gradient is provided.
[0107]
As a result, each display pixel is driven by a plurality of drive voltages according to a change in the thickness of the liquid crystal alignment layer or the insulating film layer on each display pixel. Therefore, the display is a combination of the viewing angle characteristics of a plurality of driving voltages, the viewing angle characteristics are expanded, and a liquid crystal display device having a wide viewing angle characteristic can be realized.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view illustrating a configuration of a liquid crystal display device according to an embodiment of the present invention.
FIG. 2 is a graph showing a relationship between a film thickness of a liquid crystal alignment layer used in an example of the present invention and a threshold voltage.
FIG. 3 is a graph comparing the viewing angle characteristics of contrast of a liquid crystal display device according to an embodiment of the present invention with those of a conventional example.
FIG. 4 is a cross-sectional view illustrating a configuration of a liquid crystal display device according to an embodiment of the present invention.
FIG. 5 is a cross-sectional view illustrating a configuration of a conventional liquid crystal display device.
FIG. 6 is a plan view showing a configuration of the present invention and a conventional liquid crystal display device.
FIG. 7 is a cross-sectional view illustrating a configuration of a conventional liquid crystal display device.
FIG. 8 is a diagram showing a definition of a threshold voltage in a liquid crystal display device.
FIG. 9 is a graph showing the relationship between the thickness of a liquid crystal alignment layer of a liquid crystal display device and a threshold voltage.
[Explanation of symbols]
46 Insulating film layer 51a First glass substrate 51b Second glass substrate 52a First display pixel electrode 52b Second display pixel electrode 53a First liquid crystal alignment layer 53b Second liquid crystal alignment layer 54 Seal material 55 Liquid crystal layer 57 Display pixel

Claims (6)

A first glass substrate and the second glass substrate and the display pixel electrodes provided on the liquid crystal alignment layer facing the liquid crystal display device and a liquid crystal layer provided between the first glass substrate and the second glass substrate ,
A plurality of regions having different liquid crystal alignment layers are provided on each display pixel of at least one of the first glass substrate and the second glass substrate. A liquid crystal display device characterized by improving the viewing angle characteristics by changing the voltage applied to the liquid crystal display. 2. The liquid crystal display device according to claim 1, wherein a plurality of regions having different liquid crystal alignment layers on the respective display pixels have liquid crystal alignment layers having different thicknesses . 2. The liquid crystal display device according to claim 1, wherein the plurality of regions having different heights of the liquid crystal alignment layer on each of the display pixels have a liquid crystal alignment layer provided with a film thickness gradient in which the film thickness changes continuously. . The plurality of regions having different heights of the liquid crystal alignment layer on each of the display pixels have insulating film layers having different thicknesses between the display pixel electrode and the liquid crystal alignment layer. 2. The liquid crystal display device according to 1. A plurality of regions where the height of the liquid crystal alignment layer is different on each of the display pixels is an insulating film layer having a thickness gradient in which the film thickness changes continuously between the display pixel electrode and the liquid crystal alignment layer. 2. The liquid crystal display device according to claim 1, comprising: The liquid crystal display device according to claim 4, wherein the insulating film layer is a synthetic resin layer provided on a color filter.

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