KR20110059508A - Liquid crystal display and manufacturing method of the same - Google Patents

Abstract

PURPOSE: A liquid crystal display device and manufacturing method thereof are provided to remove the afterimage problem of a video and to improve response speed, brightness, and viewing angle. CONSTITUTION: A second substrate(200) is opposite to a first substrate. A first electrode and a second electrode are formed in the first substrate. A liquid crystal layer(3) is pinched between the first substrate and the second substrate. A first alignment layer(1) contacts the liquid crystal layer on the first substrate. The first alignment layer includes a first orientation base film(12) and a first orientation controlling agent(13).

Description

Liquid crystal display and its manufacturing method {LIQUID CRYSTAL DISPLAY AND MANUFACTURING METHOD OF THE SAME}

The present invention relates to a liquid crystal display device and a manufacturing method thereof.

Currently, various kinds of flat panel display devices have been developed and used. Among them, the liquid crystal display is a flat panel display which is widely used for various purposes.

The liquid crystal display includes a twisted nematic (TN) mode liquid crystal display, a vertically aligned (VA) mode liquid crystal display, an in plane switching mode (IPS) mode liquid crystal display, and an optically compensated bend (OCB) depending on the arrangement and driving method of the liquid crystal. And mode liquid crystal display devices. In these liquid crystal display devices, the liquid crystals initially form a predetermined array due to the influence of the alignment layer or the properties of the liquid crystal itself, but when the electric field is applied, the arrangement of the liquid crystals is changed. Due to the optical anisotropy of the liquid crystals, polarization of light passing through the liquid crystals The image is displayed by changing the state depending on the arrangement state of the liquid crystal and making it appear as a difference in the amount of transmitted light using the polarizing plate.

In particular, in the IPS mode liquid crystal display, since both the common electrode and the pixel electrode are formed on one substrate, there is a problem that the aperture ratio becomes small and the luminance decreases. In addition, the IPS mode liquid crystal display device has a disadvantage in that the response speed is low because the liquid crystals near the common electrode to which the voltage is applied and the other substrate located opposite to the substrate where the pixel electrode is located do not respond quickly to the application of the electric field. .

SUMMARY OF THE INVENTION An object of the present invention is to provide an IPS mode liquid crystal display device having improved response speed, brightness, and viewing angle, and a method of manufacturing the same.

Problems to be solved by the present invention are not limited to the above-mentioned problems, and other problems not mentioned will be clearly understood by those skilled in the art from the following description.

According to an exemplary embodiment, a liquid crystal display device includes a first substrate, a second substrate facing the first substrate, a first electrode and a second electrode formed on the first substrate, the first substrate, and the A liquid crystal layer interposed between the second substrate and a first alignment layer formed on the first substrate and in contact with the liquid crystal layer, wherein the first alignment layer includes a first alignment base layer and a first alignment regulator, The first alignment base layer is a material for vertically aligning the liquid crystal of the liquid crystal layer, and the first alignment regulator extends from the inside of the first alignment base layer and preferably provides alignment force to the liquid crystal.

It is preferable that the said 1st electrode and the said 2nd electrode are a plurality of strip | belt-shaped, and they are arrange | positioned alternately with each other.

The region between the first electrode and the second electrode is preferably separated into a plurality of domains.

Preferably, the first electrode and the second electrode are parallel to each other and the center thereof is refracted.

The plurality of domains are divided into a first region and a second region, and the polar angle of the first alignment regulator positioned in the first region and the polar angle of the first alignment regulator positioned in the second region are different from each other.

It is preferable that the said 1st orientation regulator superposed | polymerized the photopolymerizable monomer or oligomer.

A second alignment layer formed on the second substrate and in contact with the liquid crystal layer, wherein the second alignment layer includes a second alignment base layer and a second alignment regulator, and the second alignment base layer is the liquid crystal layer. It is a substance which vertically orients the liquid crystal of, and it is preferable that the said 2nd orientation regulator extends out from the inside of the said 2nd orientation base film, and provides an orientation force to the said liquid crystal.

It is preferable that the said 2nd orientation regulator superposed | polymerized the photopolymerizable monomer or oligomer.

It is preferable that the polar angle of the second alignment regulator positioned in the first region and the polar angle of the second alignment regulator positioned in the second region are different from each other.

It is preferable that the said 1st alignment film and the 2nd alignment film are a photo-alignment film.

Preferably, the first electrode has a plurality of bands, the second electrode is formed of a continuous surface in the pixel region, and the second electrode is preferably formed of a transparent conductor.

Here, the region between the first electrode and the second electrode is preferably divided into a plurality of domains, and the center of the first electrode is preferably refracted.

Here, the plurality of domains are divided into a first region and a second region, and the polar angle of the first alignment regulator positioned in the first region and the polar angle of the first alignment regulator positioned in the second region are different from each other. Do.

It is preferable that the said 1st orientation regulator superposed | polymerized the photopolymerizable monomer or oligomer.

A second alignment layer formed on the second substrate and in contact with the liquid crystal layer, wherein the second alignment layer includes a second alignment base layer and a second alignment regulator, and the second alignment base layer is the liquid crystal layer. It is a substance which vertically orients the liquid crystal of, and it is preferable that the said 2nd orientation regulator extends out from the inside of the said 2nd orientation base film, and provides an orientation force to the said liquid crystal.

It is preferable that the said 2nd orientation regulator superposed | polymerized the photopolymerizable monomer or oligomer.

It is preferable that the polar angle of the second alignment regulator positioned in the first region and the polar angle of the second alignment regulator positioned in the second region are different from each other.

It is preferable that the said 1st alignment film and the 2nd alignment film are a photo-alignment film.

In addition, the method of manufacturing a liquid crystal display according to an exemplary embodiment of the present invention includes forming a first electrode and a second electrode on a first substrate, a first alignment base material for vertically aligning a liquid crystal on the first substrate, and Forming a first alignment layer comprising a monomer or oligomer made of a material different from the first alignment base material, forming a second substrate, introducing the liquid crystal between the first substrate and the second substrate, It is preferable to include a first polymerization step of applying a first voltage between the first electrode and the second electrode, and irradiates light to polymerize the monomer or oligomer included in the first alignment layer.

It is preferable that the first electrode and the second electrode have a plurality of strips and are alternately arranged.

Preferably, the region between the first electrode and the second electrode is separated into a plurality of domains.

The first electrode and the second electrode are parallel to each other, the center is preferably refracted.

The plurality of domains are separated into a first region and a second region, and the first polymerization step polymerizes the monomer or oligomer contained in the first alignment layer positioned in the first region by irradiation. Covering the second region, applying a second voltage between the first electrode and the second electrode, irradiating light to the monomer or oligomer included in the first alignment layer positioned in the second region; The method may further include a step of polymerizing, wherein the first voltage and the second voltage are different from each other.

A second alignment base material which vertically aligns the liquid crystal on the second substrate and a monomer or oligomer made of a material different from the second alignment base material before the step of bonding the first substrate and the second substrate; It is preferable to further include forming an alignment film.

Preferably, the monomer or oligomer contained in the first alignment layer is polymerized to form a first alignment regulator, and the monomer or oligomer included in the second alignment layer is polymerized to form a second alignment regulator.

Preferably, the first electrode has a plurality of bands and the second electrode has a continuous surface in the pixel area.

In addition, the manufacturing method of the liquid crystal display according to another embodiment of the present invention comprises the steps of forming a first electrode and a second electrode on the first substrate, the first alignment base material for vertically aligning the liquid crystal on the first substrate and the Forming a first alignment layer comprising a photopolymerizable monomer or oligomer made of a material different from the first alignment base material, wherein a region between the first electrode and the second electrode is divided into a plurality of domains, and the plurality of domains Is separated into a first region and a second region, and irradiates the first region with the first light to photoalign the alignment base material to form an alignment base layer, and polymerizes a photopolymerizable monomer and an oligomer to form an alignment regulator. In the step, the second region is irradiated with a second light to photoalign the alignment base material to form an alignment base layer, and to polymerize the photopolymerizable monomer and the oligomer. Comprising the step of forming a alignment control agent, the first dose of light and the second light irradiation amount is preferably different.

It is preferable that the polar angle of the orientation regulator located in the first region is different from the polar angle of the orientation regulator located in the second region.

In addition, a liquid crystal display according to another exemplary embodiment of the present invention may include a first substrate, a second substrate facing the first substrate, a control electrode formed on the first substrate, and a pixel formed on the control electrode. A pixel electrode having domain dividing means for dividing a region into a plurality of domains, a common electrode formed on the second substrate and having a continuous surface without a cutout, sandwiched between the first substrate and the second substrate. And a first alignment layer formed on the first substrate and in contact with the liquid crystal layer, wherein the first alignment layer includes a first alignment base layer and a first alignment regulator, and the first alignment base layer includes: A material for vertically aligning the liquid crystal of the liquid crystal layer, wherein the first alignment regulator extends from the inside of the first alignment base film and is disposed in the liquid crystal Providing a force, and the control electrode is preferably applied to the same voltage as the voltage applied to the pixel electrodes.

In addition, it is preferable to further include an interlayer insulating film formed between the control electrode and the pixel electrode.

The domain dividing means is preferably an incision.

The liquid crystal molecules of the liquid crystal layer positioned in the cutout may be aligned by an electric field formed between the control electrode and the common electrode.

The control electrode is preferably formed of ITO or IZO.

The first alignment regulator may be a polymerized photopolymerizable monomer or oligomer.

A second alignment layer formed on the second substrate and in contact with the liquid crystal layer, wherein the second alignment layer includes a second alignment base layer and a second alignment regulator, and the second alignment base layer is the liquid crystal layer. It is a substance which vertically orients the liquid crystal of, and it is preferable that the said 2nd orientation regulator extends out from the inside of the said 2nd orientation base film, and provides an orientation force to the said liquid crystal.

The second alignment regulator may be a polymerized photopolymerizable monomer or oligomer.

According to the exemplary embodiment of the present invention, when the liquid crystal has a pretilt in the IPS mode liquid crystal display, since the liquid crystal adjacent to the opposite substrate on which the linear common electrode and the linear pixel electrode are not positioned is immediately inclined along the pretilt, the response speed is very high. fast. Therefore, the problem of the afterimage of a moving image can be eliminated.

In addition, the linear common electrode and the linear pixel electrode are made of a transparent conductive film such as ITO or IZO, and the liquid crystals on the linear common electrode and the linear pixel electrode also have a pretilt and are immediately inclined in the direction parallel to the electric field when the driving voltage is applied. It has the effect that the liquid crystal which contributes to image display increases. Therefore, the aperture ratio is improved and the luminance is increased.

In addition, since the liquid crystal has positive dielectric anisotropy, when the electric field is applied, the liquid crystal is arranged in the same direction as the electric field formed in the direction perpendicular to the sides of the common electrode portion and the pixel electrode portion. Therefore, the liquid crystal may be arranged in different directions for each of the first to fourth domains to implement multiple alignments. That is, the liquid crystals may be arranged to have different pretilts for each of the first to fourth domains to implement multiple alignments. At this time, since the liquid crystal has a pretilt of a predetermined polar angle, when the electric field is applied, the liquid crystals of all the regions are inclined along the pretilt, so that the alignment directions of the liquid crystals located in the vicinity of the boundary line between domains are clearly different for each domain. It can be fully implemented to improve the viewing angle.

1 is a flowchart of a method of orienting liquid crystals according to an embodiment of the present invention.
2 is a layout view of a liquid crystal display according to an exemplary embodiment of the present invention.
3 is a cross-sectional view taken along line III-III of FIG. 2.
4 is a cross-sectional view illustrating a step of primary alignment of liquid crystals according to an exemplary embodiment of the present invention.
5 is a cross-sectional view illustrating a step of secondary alignment of liquid crystals according to an exemplary embodiment of the present invention.
6 is a layout view of a liquid crystal display according to another exemplary embodiment of the present invention.
FIG. 7 is a cross-sectional view taken along line VII-VII of FIG. 6.
8 and 9 illustrate a method of manufacturing a liquid crystal display according to another exemplary embodiment of the present invention.
10 and 11 illustrate a method of varying polar angles of the alignment regulators of the first region U1 and the second region U2 in the photoalignment layer.
12 is a layout view of a liquid crystal display according to another exemplary embodiment of the present invention.
FIG. 13 is a cross-sectional view taken along line XIII-XIII of FIG. 12.
14 is a layout view of a liquid crystal display according to another exemplary embodiment of the present invention.
FIG. 15 is a cross-sectional view of the liquid crystal display of FIG. 14.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but only the embodiments to complete the disclosure of the present invention, the scope of the invention to those skilled in the art to which the present invention pertains. The invention is provided by way of example, and the invention is defined by the scope of the claims. Like reference numerals refer to like elements throughout.

1 is a flowchart of a method of orienting liquid crystals according to an embodiment of the present invention.

As shown in FIG. 1, first, an IPS mode thin film transistor (TFT) substrate is manufactured (S1). The IPS mode thin film transistor substrate includes a gate line, a data line crossing the gate line, a thin film transistor having a control electrode and an input electrode connected to the gate line, and a data line on an insulating substrate, and a linear pixel electrode connected to an output terminal of the thin film transistor. And a common electrode line for applying a common voltage to the linear common electrode facing the linear pixel electrode, and the linear common electrode.

Next, a first alignment layer including a monomer or an oligomer is formed on the IPS mode thin film transistor substrate (S2). The first alignment layer may be formed by mixing and applying a photopolymerizable monomer or oligomer to the alignment base material, and curing the alignment base material. The alignment base material of the first alignment layer may be formed of a material having vertical alignment characteristics.

Therefore, the alignment layer including the photopolymerizable monomer or oligomer may serve as an alignment layer of the liquid crystal, and since the alignment base material has a vertical alignment characteristic, the director of the liquid crystal is primarily aligned perpendicular to the substrate surface.

Here, a polymerization initiator can be added together with the orientation base material and the photopolymerizable monomer or oligomer. Although it is not necessary to necessarily add a polymerization initiator, superposition | polymerization can be performed quickly by adding a polymerization initiator. As the polymerization initiator, in addition to methyl ethyl ketone peroxide, for example, benzoyl peroxide, cumene hydroperoxide, t-butyl peroctoate, dicumyl peroxide, benzoyl alkyl ether series, acetophenone series, benzophenone series, xanthone series A benzoin ether type, a benzyl ketal type polymerization initiator, etc. can be used, It can use it as it is, or can mix and use suitably. In addition, the addition amount of a polymerization initiator may be 10 weight% or less with respect to a polymeric compound. This is because adding more than 10% by weight may cause the polymerization initiator to act as an impurity and lower the display quality of the display element.

Meanwhile, an opposing substrate to be assembled to face the IPS mode thin film transistor substrate is manufactured (S3). A color filter, a light blocking member, and the like may be formed on the opposing substrate.

Next, a second alignment layer including a monomer or an oligomer is formed on the counter substrate (S4). The second alignment layer may be formed by mixing and applying a photopolymerizable monomer or oligomer to the alignment base material, and curing the alignment base material. The alignment base material of the second alignment layer may be formed of a material having vertical alignment characteristics. Therefore, the alignment layer including the photopolymerizable monomer or oligomer may serve as an alignment layer of the liquid crystal, and since the alignment base material has a vertical alignment characteristic, the director of the liquid crystal is primarily aligned perpendicular to the substrate surface.

Here, a polymerization initiator can be added together with the orientation base material and the photopolymerizable monomer or oligomer. Although it is not necessary to necessarily add a polymerization initiator, superposition | polymerization can be performed quickly by adding a polymerization initiator.

The IPS mode thin film transistor substrate and the opposing substrate thus prepared are assembled and a liquid crystal is introduced between the two substrates (S5).

Here, the introduction of the liquid crystal proceeds by a method such as injecting the liquid crystal between two substrates having an alignment layer containing a photopolymerizable monomer or oligomer. At this time, a photopolymerizable monomer or oligomer can be added and injected into a liquid crystal.

Next, an electric field is applied to the liquid crystal to change the alignment of the liquid crystal (S6). The application of the electric field to the liquid crystal may be performed using a method such as applying a voltage between the linear pixel electrode and the linear common electrode or applying a voltage between the externally installed electrodes. The change of orientation of the liquid crystal due to the application of the electric field is made according to the dielectric anisotropy of the liquid crystal, and the liquid crystal having positive dielectric anisotropy is inclined in parallel with the electric field, and the liquid crystal having negative dielectric anisotropy is perpendicular to the electric field. Inclined to In addition, the degree of change in the alignment of the liquid crystal may vary according to the intensity of the electric field.

As described above, the liquid crystal is secondarily oriented by polymerizing monomers or oligomers included in the alignment layer in a state where the alignment of the liquid crystal is changed by applying an electric field to form an alignment regulator (S7). Polymerization of the monomer or oligomer is carried out by irradiating light that induces polymerization of the photopolymerizable monomer or oligomer such as ultraviolet rays when the monomer or oligomer is a photopolymerizable material. The alignment regulators are arranged along the alignment of the liquid crystal, and maintain the alignment even after removing the applied electric field to affect the alignment of adjacent liquid crystals. Therefore, the liquid crystal may be arranged to have a pre-tilt different from the primary alignment by the secondary alignment.

In the description of the present invention, the pretilt may have an angle and a direction, and hereinafter, it will be defined as a polar angle (0-180) and an azimuthal angle (0-360), respectively. That is, the pretilt may be interpreted to include both azimuthal angle (0-360) and polar angle (0-180). Here, the azimuth angle means an angle at which the projection of the alignment film or the liquid crystal onto the substrate plane is inclined with respect to the gate line or the data line. The polar angle refers to the angle of inclination of the alignment regulator or the liquid crystal relative to a line perpendicular to the horizontal plane of the substrate (normal to the substrate plane).

This secondary orientation may be used to make the liquid crystal have a pretilt in order to determine the operation direction of the liquid crystal in advance when the electric field is applied. In particular, the pretilt in the polar direction is important in the IPS mode, which will be mainly described.

Next, an IPS mode liquid crystal display manufactured by applying the liquid crystal alignment method according to the exemplary embodiment of the present invention will be described.

2 is a layout view of a liquid crystal display according to an exemplary embodiment of the present invention, and FIG. 3 is a cross-sectional view taken along line III-III of FIG. 2.

The liquid crystal display according to the exemplary embodiment of the present invention includes a thin film transistor substrate 100, a counter substrate 200, a liquid crystal layer 3, a lower polarizer 11, and an upper polarizer 21.

The thin film transistor substrate 100 includes an insulating substrate 110 and thin film layers formed thereon, and the common electrode substrate 200 includes an insulating substrate 210 and thin film layers formed thereon.

First, the thin film transistor substrate 100 will be described.

The gate line 121 including the gate electrode 124 and the common electrode line 131 extend in the horizontal direction on the insulating substrate 110 made of transparent glass or the like. The linear common electrodes 133 and 134 are connected to the common electrode line 131. The scan signal is transmitted to the gate line 121, and the common voltage is transmitted to the common electrode line 131. The linear common electrodes 133 and 134 include a common electrode part 133 directly connected to the common electrode line 131, and a common connection part 134 connecting the other end of the common electrode part 133. The common electrode part 133 is refracted in the center. The linear common electrodes 133 and 134 may be formed of a transparent conductive film such as indium tin oxide (ITO) or indium zinc oxide (IZO).

A gate insulating layer 140 is formed on the gate line 121 and the common electrode line 131, and intrinsic semiconductors 151, 154, and 157 made of amorphous silicon are formed on the gate insulating layer 140. Resistive contact members 161, 163, 165, and 167 made of a material such as n + hydrogenated amorphous silicon doped with high concentration of silicide or n-type impurities are formed on the 151, 154, and 157. The intrinsic semiconductors 151, 154, and 157 and the ohmic contacts 161, 163, 165, and 167 may be collectively referred to as semiconductors. For semiconductors, in addition to the intrinsic semiconductor and the ohmic contact layer, a polysilicon semiconductor or an oxide semiconductor may be used. Or the like.

The linear pixel electrodes 177 and 178 are connected to the data line 171, the drain electrode 175, and the drain electrode 175 having the plurality of source electrodes 173 on the ohmic contact members 161, 163, 165, and 167. , 179 is formed. An image signal voltage is applied to the data line 171. The drain electrode 175 faces the source electrode 173 on the gate electrode 124. The channel portion of the intrinsic semiconductor 154 between the source electrode 173 and the drain electrode 175 is exposed. The linear pixel electrodes 177, 178, and 179 are directly connected to the pixel electrode portion 177 and the drain electrode 175 that extend in parallel with the common electrode portion 133 and connect one end of the pixel electrode portions 177. The second pixel connector 178 connects the first pixel connector 179 and the other end of the pixel electrode units 177. The center of the pixel electrode portion 177 is refracted similarly to the common electrode portion 133. The data line 171 is also bent to match the shapes of the pixel electrode portion 177 and the common electrode portion 133. The linear pixel electrodes 177, 178, and 179 connected to the data line 171, the drain electrode 175, and the drain electrode 175 are transparent conductive films such as indium tin oxide (ITO) or indium zinc oxide (IZO). Can be made.

The data line 171, the drain electrode 175, and the linear pixel electrodes 177, 178, and 179 may have substantially the same planar shape as the resistive contact members 161, 163, 165, and 167 below them, and may be intrinsic. The semiconductors 151, 154, and 157 may have substantially the same planar shape as the ohmic contacts 161, 163, 165, and 167 except for portions exposed between the source electrode 173 and the drain electrode 175. . Alternatively, the ohmic contact and the intrinsic semiconductor may be formed in an island shape and disposed only around the gate electrode 124.

The gate electrode 124, the source electrode 173, and the drain electrode 175 form a thin film transistor (TFT) together with the intrinsic semiconductor 154, and a channel of the thin film transistor is a source electrode 173. And a channel portion of the intrinsic semiconductor 154 between the drain electrode and the drain electrode 175.

The common electrode portion 133 and the pixel electrode portion 177 serve as domain dividing means. The common electrode portion 133 and the pixel electrode portion 177 are formed at a predetermined angle with respect to the gate line 121 in a plurality of band shapes, and are alternately arranged. The area between the common electrode part 133 and the pixel electrode part 177 is the first domain D1, the second domain D2, and the third domain around the first boundary line P1 and the second boundary line P2. (D3) and the fourth domain (D4). The first boundary line P1 is positioned between the common electrode unit 133 and the pixel electrode unit 177 and is parallel to the common electrode unit 133 and the pixel electrode unit 177, and the second boundary line P2 is It is located in the middle between adjacent gate lines 121 and is parallel to the gate line 121.

The lower alignment layer 1 is formed on the data line 171, the drain electrode 175, and the linear pixel electrodes 177, 178, and 179. The lower alignment layer 1 includes an alignment base layer 12 and an alignment regulator 13. The alignment base layer 12 is a liquid crystal vertical alignment layer such as poly-amic acid, polyimide, or lecithin, and the liquid crystal is perpendicular to the substrate by the alignment base layer 12. It is oriented based on. The orientation regulator 13 extends from the inside of the orientation base film 12 with a pretilt, especially a polar angle, and is formed by photopolymerizing a photopolymerizable monomer or oligomer.

Photopolymerizable monomers or oligomers include Reactive Mesogen (RM) and NOA series from Norland. Reactive mesogen (RM) means a polymerizable mesogenic compound. A "mesogenic compound" or "mesogenic material" includes a substance or compound comprising one or more rod-shaped, plate- or disc-shaped mesogenic groups, ie groups having the ability to induce liquid crystalline behavior. Liquid crystal compounds having rod-shaped or plate-shaped groups are known in the art as calamitic liquid crystals, and liquid crystal compounds having disc-shaped groups are known in the art as discotic liquid crystals. Compounds or materials containing mesogenic groups do not necessarily have to exhibit a liquid crystalline phase by themselves. It is also possible to exhibit liquid crystalline behavior only in mixtures with other compounds or upon polymerization of mesogenic compounds or substances, or mixtures thereof.

Reactive mesogen is a substance which is polymerized by light such as ultraviolet rays and is oriented according to the alignment state of adjacent materials. Examples of reactive mesogens include compounds represented by the following formula:

P1-A1- (Z1-A2) n-P2,

Here, P1 and P2 are independently selected from acrylate, methacrylate, vinyl, vinyloxy, and epoxy groups, and A1 and A2 are 1,4- Independently selected from phenylen and naphthalene-2,6-diyl groups, Z1 is one of COO-, OCO- and a single bond, and n is one of 0, 1 and 2 .

More specifically, there may be mentioned a compound represented by one of the following formulas:

Here, P1 and P2 are independently selected from acrylate, methacrylate, vinyl, vinyloxy and epoxy groups.

Since the base film 12 of the lower alignment layer 1 is formed of a material having vertical alignment characteristics, the liquid crystal is initially vertically aligned, but the alignment regulator 13 of the lower alignment layer 1 is formed on the surface of the insulating substrate 110. Since the pretilt has a predetermined polar angle with respect to the direction perpendicular to the direction of the liquid crystal, the alignment of the liquid crystal is changed by the alignment force of the alignment regulator 13 so that the liquid crystal is predetermined based on the direction perpendicular to the surfaces of the insulating substrates 110 and 210. It is polar and inclined.

Although not shown, an insulating film for protecting the channel portion of the intrinsic semiconductor 154 is further formed between the data line 171, the drain electrode 175, and the linear pixel electrodes 177, 178, and 179 and the lower alignment layer 1. Can be.

Next, the opposing substrate 200 will be described.

The light blocking member 220 is formed on the insulating substrate 210 made of transparent glass, and the color filter 230 is formed in each area partitioned by the light blocking member 220.

The color filter 230 and the light blocking member 220 may be formed on the thin film transistor substrate 100.

An upper alignment layer 2 is formed on the color filter 230. The upper alignment layer 2 also includes an alignment base layer 22 and an alignment regulator 23. The alignment base layer 22 is a liquid crystal vertical alignment layer such as poly-amic acid, polyimide, or lecithin, and the liquid crystal is perpendicular to the substrate by the alignment base layer 12. It is oriented based on. The orientation regulator 23 extends from the inside of the orientation base film 22 with a pretilt, especially a polar angle, and is formed by photopolymerizing a photopolymerizable monomer or oligomer.

Examples of the photopolymerizable monomer or oligomer include reactive mesogen (RM) and NOA series of Norland.

Alignment of the upper alignment layer 2 Since the base layer 22 is formed of a material having vertical alignment characteristics, the liquid crystal is initially vertically aligned, but since the alignment regulator 23 of the upper alignment layer 2 is inclined in a predetermined direction, the alignment is performed. The alignment of the liquid crystal is changed by the alignment force of the regulator 23 so that the director of the liquid crystal is inclined with a predetermined polar angle with respect to the surfaces of the substrates 110 and 210.

The liquid crystal layer 3 includes a liquid crystal having positive dielectric anisotropy, and the alignment regulators 13 and 23 are inclined with a predetermined polar angle with respect to the surfaces of the substrates 110 and 210, and the lower alignment layer 1 and the upper portion are inclined. The liquid crystal adjacent to the alignment layer 2 is inclined at a predetermined polar angle with respect to the surfaces of the substrates 110 and 210 under the influence of the alignment regulators 13 and 23 of the lower alignment layer 1 and the upper alignment layer 2.

As such, when the liquid crystals adjacent to the lower alignment layer 1 and the upper alignment layer 2 have a pretilt of a predetermined polar angle, the response speed is high because the liquid crystals of all the regions are immediately inclined along the pretilt when the electric field is applied. In particular, since the liquid crystal adjacent to the opposite substrate on which the linear common electrode and the linear pixel electrode are not positioned is immediately inclined along the pretilt, the response speed is high. Therefore, the problem of the afterimage of a moving image can be eliminated.

Further, the linear common electrodes 133 and 134 and the linear pixel electrodes 177, 178 and 179 are made of a transparent conductive film such as ITO or IZO, and the linear common electrodes 133 and 134 and the linear pixel electrodes 177 and 178. 179) The liquid crystal above has a pretilt, and when the driving voltage is applied, the liquid crystal is immediately inclined in the direction parallel to the electric field, thereby increasing the liquid crystal contributing to the image display. Therefore, the aperture ratio is improved and the luminance is increased.

In addition, since the liquid crystal has positive dielectric anisotropy, when the electric field is applied, the liquid crystal is arranged in the same direction as the electric field formed in the direction perpendicular to the sides of the common electrode 133 and the pixel electrode 177. Therefore, the liquid crystal may be arranged in different directions for each of the first to fourth domains to implement multiple alignments. That is, the liquid crystals may be arranged to have different pretilts for each of the first to fourth domains to implement multiple alignments. At this time, since the liquid crystal has a pretilt of a predetermined polar angle, when the electric field is applied, the liquid crystals of all the regions are inclined along the pretilt, so that the alignment directions of the liquid crystals located in the vicinity of the boundary line between domains are clearly different for each domain. It can be fully implemented to improve the viewing angle.

In the above, the embodiment in which the lower alignment layer 1 and the upper alignment layer 2 both have the alignment base layers 12 and 22 and the alignment polymers 13 and 23 has been described, but among the lower alignment layer 1 and the upper alignment layer 2, It is also possible that only one has an orientation base film and an orientation polymer, and the other consists only of an orientation base film.

In addition, when the photopolymerizable monomer or oligomer is added and injected into the liquid crystal, an alignment regulator which is separated from the lower alignment layer 1 and the upper alignment layer 2 may exist in the liquid crystal layer 3, and the photopolymerization is not photopolymerized. Monomers or oligomers may remain.

 The lower polarizer 11 and the upper polarizer 21 may be disposed such that transmission axes are perpendicular to each other.

A method of manufacturing a liquid crystal display according to an exemplary embodiment of the present invention will be described with reference to FIGS. 4 and 5.

4 is a cross-sectional view illustrating a step of primary alignment of liquid crystals according to an embodiment of the present invention, and FIG. 5 is a cross-sectional view illustrating a step of secondary alignment of liquid crystals according to an embodiment of the present invention.

First, as illustrated in FIG. 4, a thin film layer including various wirings, thin film transistors, linear common electrodes 133 and 134, and linear pixel electrodes 177, 178, and 179 is deposited on the insulating substrate 110. It is formed using a method such as photolithography and photo-etching. In addition, a thin film layer including the light blocking member 220 and the color filter 230 is formed on the insulating substrate 210 by using a method such as thin film deposition, photolithography, photo-etching, or the like.

Next, the alignment base material and the photopolymerizable monomer or oligomer are mixed and coated on the thin film layer of the thin film transistor substrate 100, and the heat treatment is performed by curing the alignment base material at a temperature between 100 ° C. and 180 ° C. for 0.5 to 1 hour. As a result, the lower alignment layer 1a containing the photopolymerizable monomer or oligomer is formed. In addition, by mixing and applying the orientation base material and the photopolymerizable monomer or oligomer on the thin film layer of the opposing substrate 200, and curing the orientation base material by heat treatment (Curing) 0.5 to 1 hour at a temperature between 100 ~ 180 degrees Celsius An upper alignment film 2a containing a synthetic monomer or oligomer is formed.

Here, the alignment base material is a liquid crystal vertical alignment film such as poly-amic acid, polyimide, or lecithin, and the liquid crystal is aligned in a direction perpendicular to the substrate by the alignment base material. Is oriented differently. Accordingly, the lower alignment layer 1a and the upper alignment layer 2a including the photopolymerizable monomer or the oligomer may primarily align the liquid crystal in the direction perpendicular to the substrates 100 and 200 by the alignment base material. As the photopolymerizable monomer or oligomer, the reactive mesogen (RM) described above, NOA series of Norland, etc. may be used.

Subsequently, the thin film transistor substrate 100 and the opposing substrate 200 are coupled to each other. The combination of these substrates 100 and 200 can proceed in two ways.

First, a sealant is applied to one of the thin film transistor substrate 100 and the counter substrate 200 to define a region to fill the liquid crystal, and then the liquid crystal is dropped and filled in the defined region, and the thin film transistor substrate 100 is filled. ) And a counter substrate 200 are aligned and combined. In this case, a spacer for maintaining the gap between the two substrates 100 and 200 may be dispersed before and after the liquid crystal dropping. The spacer may be formed in advance on the thin film transistor substrate 100 and the opposing substrate 200 through a thin film formation process. At this time, a photopolymerizable monomer or oligomer can be added and added dropwise to the liquid crystal.

Alternatively, a sealant may be applied to one of the thin film transistor substrate 100 and the opposite substrate 200 to define a region to fill the liquid crystal, but may have a liquid crystal injection hole, and the two substrates 100 and 200 may be aligned and coupled to each other. do. Thereafter, the liquid crystal injection hole is immersed in the liquid crystal reservoir in a vacuum state, and the liquid crystal is injected by releasing the vacuum, and then the liquid crystal injection hole may be sealed. Moreover, a photopolymerizable monomer or oligomer can also be added and inject | poured to a liquid crystal.

Next, as shown in FIG. 5, a voltage is applied between the linear pixel electrodes 177, 178, and 179 and the linear common electrodes 133 and 134 to thereby between the common electrode part 133 and the pixel electrode part 177. To form a horizontal electric field (E). The application of the electric field to the liquid crystal may be performed using a method such as applying a voltage between two electrodes previously formed on the substrate, or applying a voltage between electrodes provided outside. Since the liquid crystal has positive dielectric anisotropy, the liquid crystal is inclined in a direction parallel to the electric field. Since the electric field is formed in a direction parallel to the surface of the substrate, the liquid crystal, which was initially primarily aligned in a direction perpendicular to the substrate surface, has a predetermined polar angle by performing secondary alignment in a direction parallel to the horizontal electric field E. FIG.

Subsequently, the lower and upper alignment films 1 and 2 are irradiated with light such as ultraviolet rays to photopolymerize the photopolymerizable monomer or oligomer, thereby forming the alignment regulators 13 and 23 extending from the inside of the alignment base films 12 and 22. The alignment regulators 13 and 23 have a pretilt of a predetermined polar angle according to the secondary alignment state of the liquid crystal.

Here, the pretilt of the alignment regulators 13 and 23 may be adjusted by varying the magnitude of the voltage applied between the linear pixel electrodes 177, 178, and 179 and the linear common electrodes 133 and 134. That is, when a strong voltage is applied between the linear pixel electrodes 177, 178, and 179 and the linear common electrodes 133 and 134, the liquid crystals are arranged in a direction parallel to the horizontal electric field E. In this state, the ultraviolet rays are aligned. The regulators 13 and 23 have a large pretilt. On the contrary, when a weak voltage is applied between the linear pixel electrodes 177, 178, and 179 and the linear common electrodes 133 and 134, the liquid crystal has a small polar angle based on a direction perpendicular to the surfaces of the substrates 110 and 210. When the ultraviolet rays are irradiated in this state, the alignment regulators 13 and 23 have a small pretilt.

As such, when the photopolymerizable monomer or oligomer is mixed with the orientation base material to form the alignment film and then photopolymerized to form the alignment regulator, the pretilt control of the alignment regulator is easy, and the photopolymerizable monomer or oligomer is the liquid crystal layer 3. It can also prevent problems that may occur due to residuals.

In the above, the method of forming the alignment regulators 13 and 23 by applying a voltage and irradiating ultraviolet rays after filling the liquid crystal between the thin film transistor substrate 100 and the counter substrate 200 has been described. An alignment layer including a photopolymerizable monomer or oligomer by applying a voltage between the linear pixel electrodes 177, 178, and 179 and the linear common electrodes 133 and 134 without filling the liquid crystal between the substrate 100 and the counter substrate 200. Ultraviolet rays may be irradiated to (1, 2) to form the alignment regulators 13 and 23. The liquid crystal is injected after the alignment regulators 13 and 23 are formed.

After that, the module works.

On the other hand, by varying the polar angle of the liquid crystal located in different areas to improve the compensation rate of the optical characteristics between different areas to improve the side visibility, which will be described in other embodiments below.

FIG. 6 is a layout view of a liquid crystal display according to another exemplary embodiment. FIG. 7 is a cross-sectional view taken along line VII-VII of FIG. 6.

This embodiment is located in the first area U1 and the second area by different pretilts of the polar angles of the alignment regulators of the first area U1 and the second area compared with the embodiments shown in FIGS. 2 and 3. Except for the structure in which the polar angles of the liquid crystals are different from each other, the repeated description is omitted.

6 and 7, the area between the common electrode part 133 and the pixel electrode part 177 in the liquid crystal display according to another exemplary embodiment of the present invention is the first boundary line P1 and the second boundary line. It is divided into a first domain D1, a second domain D2, a third domain D3, and a fourth domain D4 around (P2). The first boundary line P1 is positioned between the common electrode unit 133 and the pixel electrode unit 177 and is parallel to the common electrode unit 133 and the pixel electrode unit 177, and the second boundary line P2 is It is located in the middle between adjacent gate lines 121 and is parallel to the gate line 121.

When the thin film transistor substrate 100 and the opposing substrate 200 are aligned, the linear common electrodes 133 and 134 and the linear pixel electrodes 177, 178, and 179 may form portions of the liquid crystal layer 300 in a plurality of subregions. ). These small regions are classified into eight types according to the directors of the liquid crystals located therein when the electric field is applied, and are called domains.

As such, when the thin film transistor substrate 100 and the opposing substrate 200 are aligned, the linear common electrodes 133 and 134 and the linear pixel electrodes 177, 178, and 179 divide the pixel region into a plurality of domains, and The electric field formed when the voltage is applied between the common electrodes 133 and 134 and the linear pixel electrodes 177, 178 and 179 has a horizontal component with respect to the substrates 110 and 210 to control the inclination direction of the liquid crystal. Play a role.

These domains are classified into four types according to the directors of the liquid crystals located therein, and each domain is elongated to have a width and a length. Within these domains, the arrangement of liquid crystals is regular, so that the viewing angle of the liquid crystal display device is extended. In FIG. 6, four first domains D1, four second domains D2, four third domains D3, and four fourth domains D4 are illustrated, and the first region U1 is illustrated in FIG. 6. One of the first to fourth domains is included, and the second region U2 includes the other of the first to fourth domains.

The lower alignment layer 1 includes an alignment base layer 12 and an alignment regulator 13. The alignment base layer 12 is a liquid crystal vertical alignment layer such as poly-amic acid, polyimide, or lecithin, and the liquid crystal is perpendicular to the substrate by the alignment base layer 12. It is oriented based on. The orientation regulator 13 extends from the inside of the orientation base film 12 with a pretilt, especially a polar angle, and is formed by photopolymerizing a photopolymerizable monomer or oligomer. At this time, the polar angle β1 of the alignment regulator 13 positioned in the first region U1 is different from the polar angle β2 of the alignment regulator 13 positioned in the second region U2.

The upper alignment layer 2 also includes an alignment base layer 22 and an alignment regulator 23. The alignment base layer 22 is a liquid crystal vertical alignment layer such as poly-amic acid, polyimide, or lecithin, and the liquid crystal is perpendicular to the substrate by the alignment base layer 12. It is oriented based on. The orientation regulator 23 extends from the inside of the orientation base film 22 with a pretilt, especially a polar angle, and is formed by photopolymerizing a photopolymerizable monomer or oligomer. At this time, the polar angle β1 of the alignment regulator 13 positioned in the first region U1 is different from the polar angle β2 of the alignment regulator 13 positioned in the second region U2.

The liquid crystal layer 3 includes a liquid crystal having positive dielectric anisotropy, and the alignment regulators 13 and 23 are inclined with a predetermined polar angle with respect to the surfaces of the substrates 110 and 210, and the lower alignment layer 1 and the upper portion are inclined. The liquid crystal adjacent to the alignment layer 2 is inclined at a predetermined polar angle with respect to the surfaces of the substrates 110 and 210 under the influence of the alignment regulators 13 and 23 of the lower alignment layer 1 and the upper alignment layer 2.

As such, when the liquid crystals adjacent to the lower alignment layer 1 and the upper alignment layer 2 have a pretilt of a predetermined polar angle, the response speed is high because the liquid crystals of all the regions are immediately inclined along the pretilt when the electric field is applied. In particular, since the liquid crystal adjacent to the opposite substrate on which the linear common electrode and the linear pixel electrode are not positioned is immediately inclined along the pretilt, the response speed is high. Therefore, the problem of the afterimage of a moving image can be eliminated.

The alignment regulators 13 and 23 affect the alignment of adjacent liquid crystals, and the alignment regulators 13 and 23 of the alignment regulators 13 and 23 positioned in the first domain D1 and the second domain D2 of the first region U1. The polar angle β1 is greater than the pretilt angle β2 of the alignment polymers 13 and 23 positioned in the first domain D1 and the second domain D2 of the second region U2, and thus, the first region U1. The polar angle α2 of the liquid crystal adjacent to the lower and upper alignment layers 1 and 2 positioned in the first domain D1 and the second domain D2 of the first and second domains D1 and D2 It is larger than the polar angle α2 of the liquid crystal adjacent to the lower and upper alignment layers 1 and 2 positioned in the second domain D2.

Accordingly, when the voltage is applied according to the polar angles of the liquid crystal adjacent to the lower and upper alignment layers 1 and 2, all liquid crystals of the liquid crystal layer 3 immediately incline in the pretilt direction, at which time the first domain of the first region U1 is The polar angle of the liquid crystal positioned in the D1 and the second domain D2 is greater than the polar angle of the liquid crystal positioned in the first domain D1 and the second domain D2 of the second region U2. Therefore, since the gamma curves between the first region U1 and the second region U2 are different from each other, optical characteristics between the first region U1 and the second region U2 are effectively compensated for each other, thereby improving side visibility.

In the above, the embodiment in which the lower alignment layer 1 and the upper alignment layer 2 both have the alignment base layers 12 and 22 and the alignment polymers 13 and 23 has been described, but among the lower alignment layer 1 and the upper alignment layer 2, It is also possible that only one has an orientation base film and an orientation polymer, and the other consists only of an orientation base film.

8 and 9 illustrate a method of manufacturing a liquid crystal display according to another exemplary embodiment of the present invention.

First, as illustrated in FIG. 4, a thin film layer including various wirings, thin film transistors, linear common electrodes 133 and 134, and linear pixel electrodes 177, 178, and 179 is deposited on the insulating substrate 110. It is formed using a method such as photolithography and photo-etching. In addition, a thin film layer including the light blocking member 220 and the color filter 230 is formed on the insulating substrate 210 by using a method such as thin film deposition, photolithography, photo-etching, or the like.

Next, the alignment base material and the photopolymerizable monomer or oligomer are mixed and coated on the thin film layer of the thin film transistor substrate 100, and the heat treatment is performed by curing the alignment base material at a temperature between 100 ° C. and 180 ° C. for 0.5 to 1 hour. As a result, the lower alignment layer 1a containing the photopolymerizable monomer or oligomer is formed. In addition, by mixing and applying the orientation base material and the photopolymerizable monomer or oligomer on the thin film layer of the opposing substrate 200, and curing the orientation base material by heat treatment (Curing) 0.5 to 1 hour at a temperature between 100 ~ 180 degrees Celsius An upper alignment film 2a containing a synthetic monomer or oligomer is formed.

Here, the alignment base material is a liquid crystal vertical alignment film such as poly-amic acid, polyimide, or lecithin, and the liquid crystal is aligned in a direction perpendicular to the substrate by the alignment base material. Is oriented differently. Accordingly, the lower alignment layer 1a and the upper alignment layer 2a including the photopolymerizable monomer or the oligomer may primarily align the liquid crystal in the direction perpendicular to the substrates 100 and 200 by the alignment base material. As the photopolymerizable monomer or oligomer, the reactive mesogen (RM) described above, NOA series of Norland, etc. may be used.

Subsequently, the thin film transistor substrate 100 and the opposing substrate 200 are coupled to each other.

Next, as shown in FIGS. 8 and 9, the liquid crystal is rearranged by applying a first electric field between the common electrode unit 133 and the pixel electrode unit 177. At this time, the inclination angle α1 of the liquid crystal is also increased by increasing the intensity of the first electric field. Subsequently, the photomask 4 having the same shape as the second region U2 in the pixel region is positioned on the second region U2 and irradiated with light such as ultraviolet rays. Therefore, light is irradiated only to the 1st area | region U1 which is not covered by the photomask 4. As shown in FIG. At this time, since the monomers or oligomers included in the lower and upper alignment layers 1 and 2 are photopolymerizable materials, the monomers or oligomers are photopolymerized by light such as ultraviolet rays, and the alignment regulators 13, 23) stretches out. These alignment regulators 13 and 23 are formed only in the first region U1. The alignment regulators 13 and 23 formed in the first region U1 have polar angles according to the arrangement state of the liquid crystals. Therefore, since the liquid crystal had a large polar angle due to the first electric field of high intensity, the alignment regulators 13 and 23 located in the first region U1 have a large polar angle β1.

Next, as shown in FIG. 7, the liquid crystal is rearranged by applying a second electric field between the common electrode 133 and the pixel electrode 177. The intensity of the second electric field is smaller than that of the first electric field so that the polar angle α2 of the liquid crystal is also smaller than when the first electric field is applied. Subsequently, light is irradiated to both the first region U1 and the second region U2 by irradiating light such as ultraviolet rays without a separate photo mask. At this time, the monomers or oligomers included in the lower and upper alignment layers 1 and 2 are photopolymerized to extend the alignment regulators 13 and 23 from inside the alignment base layers 12 and 22. The alignment regulators 13 and 23 are formed only in the second region U2, and the alignment regulator having a pretilt fixed therein is formed in the first region U1. The alignment regulators 13 and 23 formed in the second region U2 have a pretilt of polar angle depending on the arrangement state of the liquid crystal. Therefore, since the liquid crystal has a small inclination angle α2 due to the second electric field of small intensity, the polar angle β2 of the alignment regulators 13 and 23 positioned in the second region U2 is in the first region U1. It becomes smaller than the pretilt angle (beta) 1 of the orientation regulators 13 and 23 located.

In this case, the liquid crystal adjacent to the lower alignment layer 1 and the upper alignment layer 2 has a polar angle under the influence of the alignment regulators 13 and 23 of the lower alignment layer 1 and the upper alignment layer 2, and the second region U2 is formed. The polar angle α2 of the liquid crystal adjacent to the lower and upper alignment layers 1 and 2 positioned at is smaller than the polar angle α1 of the liquid crystal adjacent to the lower and upper alignment layers 1 and 2 positioned at the first region U1. .

Therefore, according to the pretilt of the liquid crystal adjacent to the lower and upper alignment layers 1 and 2, all liquid crystals of the liquid crystal layer are immediately inclined in the pretilt direction when voltage is applied, and all liquid crystals positioned in the first region U1 are The polar angle α1 of the is larger than the polar angle α2 of all liquid crystals positioned in the second region U2. Therefore, since the gamma curves between the first region U1 and the second region U2 are different from each other, optical characteristics between different regions are effectively compensated for each other, thereby improving side visibility.

Thereafter, the polarizing plates 11 and 21 are attached and the module work is performed.

In the above, the side visibility is improved by changing the polar angles of the alignment regulators in different regions by using photo masks, thereby increasing the compensation rate of the optical characteristics between the different regions. By varying the polar angles of the alignment regulators in different regions, the polar angles of the liquid crystals positioned in the different regions may be changed to increase the compensation ratio of the optical characteristics between the different regions, thereby improving side visibility.

10 and 11 illustrate methods of varying polar angles of the alignment regulators of the first region U1 and the second region U2 in the photoalignment layer.

As shown in FIG. 10, a thin film layer including various wirings, thin film transistors, linear common electrodes 133 and 134, and linear pixel electrodes 177, 178, and 179 is deposited on a insulating substrate 110, and a photolithography process ( Form using photolithography, photo-etching, and the like. The alignment base material and the photopolymerizable monomer or oligomer are mixed and coated on the thin film layer of the thin film transistor substrate 100 to form the alignment material 400. Then, the first region U1 is irradiated with UV to photoalign the alignment base material to form the alignment base layer 13, and the photopolymerizable monomer and the oligomer are polymerized to form the alignment regulator 12. Here, when UV is irradiated to the first region U1, the second region U2 blocks the UV by using the photo mask 600. At this time, the polar angle β1 of the alignment regulator 13 positioned in the first region U1 is largely formed by adjusting the amount of UV.

Next, as shown in FIG. 11, the second base area U2 is irradiated with UV to photoalign the alignment base material to photoalign the alignment base layer 13, and to polymerize the photopolymerizable monomer and the oligomer to form the alignment regulator 12. ) Is formed to complete the lower alignment layer 1. Here, when UV is irradiated to the second region U2, the first region U2 blocks the UV by using the photo mask 600. At this time, the polar angle β2 of the alignment regulator 13 positioned in the second region U2 is smaller than the polar angle β1 of the alignment regulator 13 positioned in the first region U1 by adjusting the amount of UV. do.

Next, the counter substrate 200 also forms the upper alignment layer 2 in the same manner as the thin film transistor substrate 100, and combines the thin film transistor substrate 100 and the counter substrate 200.

In this case, the liquid crystal adjacent to the lower alignment layer 1 and the upper alignment layer 2 has a polar angle under the influence of the alignment regulators 13 and 23 of the lower alignment layer 1 and the upper alignment layer 2, and the second region U2 is formed. The polar angle α2 of the liquid crystal adjacent to the lower and upper alignment layers 1 and 2 positioned at is smaller than the polar angle α1 of the liquid crystal adjacent to the lower and upper alignment layers 1 and 2 positioned at the first region U1. .

Therefore, according to the pretilt of the liquid crystal adjacent to the lower and upper alignment layers 1 and 2, all liquid crystals of the liquid crystal layer are immediately inclined in the pretilt direction when voltage is applied, and all liquid crystals positioned in the first region U1 are The polar angle α1 of the is larger than the polar angle α2 of all liquid crystals positioned in the second region U2. Therefore, since the gamma curves between the first region U1 and the second region U2 are different from each other, optical characteristics between different regions are effectively compensated for each other, thereby improving side visibility.

Although the present invention is applied to an IPS mode liquid crystal display device, the present invention is also applicable to a FFS (Fringe Field Switching) mode liquid crystal display device.

FIG. 12 is a layout view of a liquid crystal display according to yet another exemplary embodiment. FIG. 13 is a cross-sectional view taken along line XIII-XIII of FIG. 12.

12 and 13, most of the structures are the same as those of FIGS. 2 and 3, and only the structure of the common electrode is distinguished from each other. This difference is mainly explained.

The common electrode 130 is formed on the insulating substrate 110, and the common electrode 130 is formed of a continuous surface without a separated portion in the pixel area. The common electrode 130 overlaps the pixel electrode 190 and has an opening 132 in a portion overlapping the data line 171. The common electrode 130 may be made of a transparent conductive material such as indium tin oxide (ITO) or indium zinc oxide (IZO).

A passivation layer 180 is formed on the data line 171, the drain electrode 175, and the drain electrode 175 having the plurality of source electrodes 173, and a portion of the drain electrode 175 is exposed on the passivation layer 180. The contact hole 185 is formed. The pixel electrode 190 is connected to a part of the drain electrode 175 through the contact hole 185. The pixel electrode 190 is formed long in the vertical direction in the form of a plurality of bands. The common electrode 130 and the pixel electrode 190 serve as domain dividing means, and a region between the common electrode 130 and the pixel electrode 190 is first around the first and second boundary lines P1 and P2. Domain D1 to the fourth domain D4. The lower alignment layer 1 is formed on the pixel electrode 190. The lower alignment layer 1 includes an alignment base layer 12 and an alignment regulator 13. The alignment base layer 12 is a liquid crystal vertical alignment layer such as poly-amic acid, polyimide, or lecithin, and the liquid crystal is perpendicular to the substrate by the alignment base layer 12. It is oriented based on. The orientation regulator 13 extends from the inside of the orientation base film 12 with a pretilt, especially a polar angle, and is formed by photopolymerizing a photopolymerizable monomer or oligomer.

Since the base film 12 of the lower alignment layer 1 is formed of a material having vertical alignment characteristics, the liquid crystal is initially vertically aligned, but the alignment regulator 13 of the lower alignment layer 1 is formed on the surface of the insulating substrate 110. Since the pretilt has a predetermined polar angle with respect to the direction perpendicular to the direction of the liquid crystal, the alignment of the liquid crystal is changed by the alignment force of the alignment regulator 13 so that the liquid crystal is predetermined based on the direction perpendicular to the surfaces of the insulating substrates 110 and 210. It is polar and inclined.

In addition, the light blocking member 220 is formed on the insulating substrate 210, and the color filter 230 is formed in each region partitioned by the light blocking member 220.

The color filter 230 and the light blocking member 220 may be formed on the thin film transistor substrate 100.

An upper alignment layer 2 is formed on the color filter 230. The upper alignment layer 2 also includes an alignment base layer 22 and an alignment regulator 23. The alignment base layer 22 is a liquid crystal vertical alignment layer such as poly-amic acid, polyimide, or lecithin, and the liquid crystal is perpendicular to the substrate by the alignment base layer 12. It is oriented based on. The orientation regulator 23 extends from the inside of the orientation base film 22 with a pretilt, especially a polar angle, and is formed by photopolymerizing a photopolymerizable monomer or oligomer.

Alignment of the upper alignment layer 2 Since the base layer 22 is formed of a material having vertical alignment characteristics, the liquid crystal is initially vertically aligned, but since the alignment regulator 23 of the upper alignment layer 2 is inclined in a predetermined direction, the alignment is performed. The alignment of the liquid crystal is changed by the alignment force of the regulator 23 so that the director of the liquid crystal is inclined with a predetermined polar angle with respect to the surfaces of the substrates 110 and 210.

The liquid crystal layer 3 includes a liquid crystal having positive dielectric anisotropy, and the alignment regulators 13 and 23 are inclined with a predetermined polar angle with respect to the surfaces of the substrates 110 and 210, and the lower alignment layer 1 and the upper portion are inclined. The liquid crystal adjacent to the alignment layer 2 is inclined at a predetermined polar angle with respect to the surfaces of the substrates 110 and 210 under the influence of the alignment regulators 13 and 23 of the lower alignment layer 1 and the upper alignment layer 2.

As such, when the liquid crystals adjacent to the lower alignment layer 1 and the upper alignment layer 2 have a pretilt of a predetermined polar angle, the response speed is high because the liquid crystals of all the regions are immediately inclined along the pretilt when the electric field is applied.

In the case of the IPS mode liquid crystal display, since the electric field located in the region between the common electrode and the pixel electrode decreases away from the common electrode and the pixel electrode, the threshold voltage is high and power consumption is high, and both the common electrode and the pixel electrode There is a problem that the aperture ratio is reduced because it is formed on one substrate. In order to solve this problem, the FFS mode liquid crystal display improves the electric field intensity by forming the common electrode in a continuous plane in the pixel region, and improves the aperture ratio by forming the common electrode as a transparent conductor.

Meanwhile, an embodiment in which the liquid crystal alignment method according to the exemplary embodiment of the present invention is applied to the liquid crystal display device in the vertical alignment mode will be described.

14 is a layout view of a liquid crystal display according to another exemplary embodiment. FIG. 15 is a cross-sectional view of the liquid crystal display of FIG. 14.

In another exemplary embodiment, a liquid crystal display device includes a thin film transistor substrate 100, a common electrode substrate 200, a liquid crystal layer 3, a lower polarizer 11, an upper polarizer 21, and a compensation film 24. It includes.

The thin film transistor substrate 100 includes an insulating substrate 110 and thin film layers formed thereon, and the common electrode substrate 200 includes an insulating substrate 210 and thin film layers formed thereon.

First, the thin film transistor substrate 100 will be described.

The gate electrode 124 is formed on the insulating substrate 110 made of transparent glass or the like. The gate electrode 124 receives a scan signal through the gate line 121.

A gate insulating layer 140 is formed on the gate electrode 124, and an intrinsic semiconductor 154 made of amorphous silicon is formed on the gate insulating layer 140, and silicide or n-type is formed on the intrinsic semiconductor 154. Resistive contact members 163 and 165 made of a material such as n + hydrogenated amorphous silicon doped with a high concentration of impurities are formed. The intrinsic semiconductor 154 and the ohmic contacts 163 and 165 may be collectively referred to as semiconductors, and the semiconductor may mean a polycrystalline silicon semiconductor or an oxide semiconductor in addition to the intrinsic semiconductor and the ohmic contact layer.

A plurality of source electrodes 173 and drain electrodes 175 are formed on the ohmic contacts 163 and 165. The source electrode 173 receives an image signal voltage from the data line 171. The drain electrode 175 faces the source electrode 173 on the gate electrode 124. The channel portion of the intrinsic semiconductor 154 between the source electrode 173 and the drain electrode 175 is exposed.

The gate electrode 124, the source electrode 173, and the drain electrode 175 form a thin film transistor (TFT) together with the intrinsic semiconductor 154, and a channel of the thin film transistor is a source electrode 173. And a channel portion of the intrinsic semiconductor 154 between the drain electrode and the drain electrode 175.

A passivation layer 180 having a contact hole 185 is formed on the channel portion of the gate insulating layer 140, the source electrode 173, the drain electrode 174, and the intrinsic semiconductor 154. The passivation layer 180 may be made of an inorganic insulating material such as silicon nitride or silicon oxide or an organic insulating material such as resin.

The control electrode 19 is formed on the passivation layer 180. The control electrode 19 is made of a transparent conductive film such as indium tin oxide (ITO) or indium zinc oxide (IZO), and the same voltage as that applied to the pixel electrode 190 is applied. The interlayer insulating film 183 is formed on the control electrode 19. The interlayer insulating layer 183 is formed between the pixel electrode 190 and the control electrode 19 to prevent the pixel electrode 190 and the control electrode 19 from being short-circuited, and the interlayer insulating layer 183 is formed of silicon nitride or oxide. It may be made of an inorganic insulating material such as silicon or an organic insulating material such as resin.

The pixel electrode 190 is formed on the interlayer insulating layer 183. The pixel electrode 190 is connected to the drain electrode 175 through the contact hole 185 and may be formed of a transparent conductive film such as indium tin oxide (ITO) or indium zinc oxide (IZO). The pixel electrode 190 has a cutout 191 serving as a domain dividing means. The cutout 191 controls the inclination direction of the liquid crystal so that an electric field formed when a voltage is applied between the pixel electrode 190 and the common electrode 270 has a horizontal component with respect to the substrate 210. . As a result, the liquid crystal layer 3 is divided into various regions, and the viewing angle of the liquid crystal display is expanded by having the arrangement of the liquid crystals in the divided regions. The pixel electrode 190 receives a data voltage from the drain electrode 175.

The lower alignment layer 1 is formed on the pixel electrode 190. The lower alignment layer 1 includes an alignment base layer 12 and an alignment polymer 13. The alignment base layer 12 is a material generally used as a liquid crystal alignment layer such as poly-amic acid, polyimide, lecithin, nylon, nylon, or polyvinylalcohol (PVA). It may comprise at least one of. Therefore, the liquid crystal is based on the orientation of the alignment base film 12. The alignment polymer 13 extends from the inside of the alignment base film 12, and may be formed by photopolymerizing a photopolymerizable monomer or oligomer.

The alignment polymer 13 of the lower alignment layer 1 may have a pre-tilt inclined away from the cutout 191 of the pixel electrode 190.

Next, the common electrode substrate 200 will be described.

The light blocking member 220 is formed on the insulating substrate 210 made of transparent glass, and the color filter 230 is formed in each area partitioned by the light blocking member 220. An overcoat 250 is formed on the color filter 230, and a common electrode 270 is formed on the overcoat 250.

The common electrode 270 does not have an incision and forms a continuous surface.

The overcoat 250 may be omitted, and the color filter 230 and the light blocking member 220 may be formed on the thin film transistor substrate 100.

An upper alignment layer 2 is formed on the common electrode 270. The upper alignment film 2 also includes an alignment base film 22 and an alignment polymer 23. The alignment base layer 22 is a material generally used as a liquid crystal alignment layer such as polyamic acid, polyimide, lecithin, nylon, polyvinylalcohol, or PVA. It may comprise at least one of. Therefore, the liquid crystal is based on the orientation of the alignment base film 22. The alignment polymer 23 extends from the inside of the alignment base film 22, and may be formed by photopolymerizing a photopolymerizable monomer or oligomer.

Examples of the photopolymerizable monomer or oligomer include reactive mesogen (RM) and NOA series of Norland.

The alignment polymer 23 of the upper alignment layer 2 has a pre-tilt inclined in the same direction as the alignment polymer 13 of the lower alignment layer 1 at the corresponding position.

The liquid crystal layer 3 includes a liquid crystal having negative dielectric anisotropy, and is vertically arranged with respect to the substrates 110 and 210 by the alignment force of the alignment base films 12 and 22, and the lower alignment film 1 and the upper alignment film. The liquid crystal adjacent to (2) has a pre-tilt due to the influence of the alignment polymer of the lower alignment film 1 and the upper alignment film 2.

As such, when the liquid crystal has a pretilt, the response speed is very fast since the liquid crystals of all the regions are immediately inclined in the pretilt direction when the electric field is applied. Therefore, the problem of the afterimage of a moving image can be eliminated.

On the other hand, since the electric field does not work well on the liquid crystal molecules 31 located in the cutout 191, the liquid crystal molecules 31 located in the cutout 191 are not aligned in the direction of the electric field, resulting in texture. This leads to a decrease in the overall transmittance. However, as in the present exemplary embodiment, the liquid crystal molecules 31 positioned in the cutout 191 are formed under the pixel electrode 190 by forming the control electrode 19 to which the same voltage as the voltage applied to the pixel electrode 190 is applied. Let the electric field work. Therefore, the transmittance may be improved by controlling the liquid crystal molecules 31 positioned in the cutout 191.

In the above, the embodiment in which the lower alignment layer 1 and the upper alignment layer 2 both have the alignment base layers 12 and 22 and the alignment polymers 13 and 23 has been described, but among the lower alignment layer 1 and the upper alignment layer 2, It is also possible that only one has an orientation base film and an orientation polymer, and the other consists only of an orientation base film.

 The lower polarizer 11 and the upper polarizer 21 may be disposed such that transmission axes are perpendicular to each other.

The compensation film 24 may be a phase retardation film such as a quarter-wave retardation film or a half-wave retardation film. Two or more compensation films 24 may be included or omitted.

Although the embodiments of the present invention have been described above with reference to the accompanying drawings, those skilled in the art to which the present invention pertains may implement the present invention in other specific forms without changing the technical spirit or essential features thereof. I can understand that. Therefore, it should be understood that the embodiments described above are exemplary in all respects and not restrictive.

1: lower alignment layer 2: upper alignment layer
12, 22: orientation base film 13, 23: orientation regulator
133: common electrode portion 177: pixel electrode portion

Claims (30)

First substrate,
A second substrate facing the first substrate,
A first electrode and a second electrode formed on the first substrate,
A liquid crystal layer sandwiched between the first substrate and the second substrate,
A first alignment layer formed on the first substrate and in contact with the liquid crystal layer
Including,
The first alignment layer includes a first alignment base layer and a first alignment regulator, wherein the first alignment base layer is a material for vertically aligning the liquid crystal of the liquid crystal layer, and the first alignment regulator is formed from inside the first alignment base layer. A liquid crystal display device that extends and provides an alignment force to the liquid crystal. In claim 1,
The first electrode and the second electrode have a plurality of bands and are alternately arranged. In claim 2,
The region between the first electrode and the second electrode is divided into a plurality of domains. 4. The method of claim 3,
The first electrode and the second electrode are parallel to each other, the center is refracted liquid crystal display device. 4. The method of claim 3,
The plurality of domains are divided into a first region and a second region,
The polar angle of the first alignment regulator positioned in the first region and the polar angle of the first alignment regulator positioned in the second region are different from each other. In claim 5,
The first alignment regulator is a liquid crystal display device obtained by polymerizing a photopolymerizable monomer or oligomer. In claim 5,
A second alignment layer formed on the second substrate and in contact with the liquid crystal layer;
The second alignment layer includes a second alignment base layer and a second alignment adjuster, the second alignment base layer is a material for vertically aligning the liquid crystal of the liquid crystal layer, and the second alignment adjuster is formed from inside the second alignment base layer. A liquid crystal display device which extends and provides an alignment force to the liquid crystal. In claim 7,
And said second alignment regulator is a polymerized photopolymerizable monomer or oligomer. 9. The method of claim 8,
The polar angle of the second alignment regulator positioned in the first region and the polar angle of the second alignment regulator positioned in the second region are different from each other. In claim 9,
The first alignment layer and the second alignment layer are liquid crystal display devices. In claim 1,
The first electrode has a plurality of bands, and the second electrode has a continuous surface in the pixel area. In claim 11,
And the second electrode is formed of a transparent conductor. In claim 12,
The region between the first electrode and the second electrode is divided into a plurality of domains. In claim 13,
The first electrode is a liquid crystal display device is refracted in the center. In claim 13,
The plurality of domains are divided into a first region and a second region,
The polar angle of the first alignment regulator positioned in the first region and the polar angle of the first alignment regulator positioned in the second region are different from each other. The method of claim 15,
The first alignment regulator is a liquid crystal display device obtained by polymerizing a photopolymerizable monomer or oligomer. The method of claim 15,
A second alignment layer formed on the second substrate and in contact with the liquid crystal layer;
The second alignment layer includes a second alignment base layer and a second alignment adjuster, the second alignment base layer is a material for vertically aligning the liquid crystal of the liquid crystal layer, and the second alignment adjuster is formed from inside the second alignment base layer. A liquid crystal display device which extends and provides an alignment force to the liquid crystal. The method of claim 17,
And said second alignment regulator is a polymerized photopolymerizable monomer or oligomer. The method of claim 18,
The polar angle of the second alignment regulator positioned in the first region and the polar angle of the second alignment regulator positioned in the second region are different from each other. The method of claim 19,
The first alignment layer and the second alignment layer are liquid crystal display devices. Forming a first electrode and a second electrode on the first substrate,
Forming a first alignment layer on the first substrate, the first alignment layer including a first alignment base material for vertically aligning a liquid crystal and a monomer or oligomer made of a material different from the first alignment base material;
Forming a second substrate,
Introducing the liquid crystal between the first substrate and the second substrate,
A first polymerization step of applying a first voltage between the first electrode and the second electrode and irradiating light to polymerize the monomer or oligomer included in the first alignment layer
Method of manufacturing a liquid crystal display comprising a. 22. The method of claim 21,
The first electrode and the second electrode is a plurality of bands, the method of manufacturing a liquid crystal display device alternately arranged. The method of claim 22,
The area between the first electrode and the second electrode is divided into a plurality of domains. The method of claim 23,
The first electrode and the second electrode are parallel to each other, the center is refracted manufacturing method of the liquid crystal display device. The method of claim 23,
The plurality of domains are divided into a first region and a second region,
The first polymerization step is carried out to polymerize the monomer or oligomer contained in the first alignment layer positioned in the first region,
Covering the second area with a photo mask,
Applying a second voltage between the first electrode and the second electrode and irradiating light to polymerize the monomer or oligomer included in the first alignment layer positioned in the second region;
Further comprising:
The method of claim 1, wherein the first voltage and the second voltage are different from each other. 26. The method of claim 25,
Before joining the first substrate and the second substrate
And forming a second alignment layer on the second substrate, the second alignment layer including a second alignment base material for vertically aligning the liquid crystal and a monomer or oligomer made of a material different from the second alignment base material. Way. The method of claim 26,
Manufacturing a liquid crystal display device which polymerizes the monomer or oligomer included in the first alignment layer to form a first alignment regulator and simultaneously polymerizes the monomer or oligomer included in the second alignment layer to form a second alignment regulator. Way. 22. The method of claim 21,
The first electrode has a plurality of bands, and the second electrode is formed in a continuous surface in the pixel area. Forming a first electrode and a second electrode on the first substrate,
Forming a first alignment layer on the first substrate, the first alignment layer including a first alignment base material for vertically aligning a liquid crystal and a photopolymerizable monomer or oligomer made of a material different from the first alignment base material;
The region between the first electrode and the second electrode is divided into a plurality of domains, and the plurality of domains are separated into a first region and a second region,
Irradiating a first light to the first region to photoalign the alignment base material to form an alignment base layer, and polymerizing a photopolymerizable monomer and an oligomer to form an alignment regulator;
Irradiating a second light to the second region to photoalign the alignment base material to form an alignment base layer, and polymerizing a photopolymerizable monomer and an oligomer to form an alignment regulator.
Including,
The method of manufacturing a liquid crystal display device, wherein the irradiation amount of the first light and the irradiation amount of the second light are different from each other. The method of claim 29,
The polar angle of the alignment regulator positioned in the first region is different from the polar angle of the alignment regulator positioned in the second region.

Images