KR100929667B1 - Liquid crystal display with improved viewing angle and manufacturing method thereof - Google Patents

Abstract

 On the first substrate, the pixel electrode formed on the first substrate, the organic insulating film formed on the predetermined region of the upper surface of the pixel electrode, the second substrate positioned at an upper portion spaced apart from the first substrate by a predetermined distance, and the bottom surface of the second substrate A liquid crystal display comprising the formed black matrix, a color filter and a reference electrode, and a liquid crystal injected between the first substrate and the second substrate, and a manufacturing method thereof.

Liquid crystal display, viewing angle, side visibility, organic insulating film, luminance

Description

Liquid crystal display device with improved viewing angle and manufacturing method therefor {LIQUID CRYSTAL DISPLAY HAVING IMPROVED VIEWING ANGLE AND MANUFACTURING METHOD THEREOF}

1 is a simplified layout view of a liquid crystal display of a first embodiment according to the present invention;

2A and 2B are cross-sectional views of the liquid crystal display device according to the first exemplary embodiment of the present invention, taken along the line II-II ′ of FIG. 1, respectively, with no voltage applied thereto and a voltage applied thereto. Represents the arrangement of liquid crystal molecules,

3 is a relation curve of transmittance with respect to an applied voltage,

4A to 4D are cross-sectional views illustrating a method of manufacturing a color filter substrate of a liquid crystal display according to a first embodiment of the present invention, in order of process;

5 is a simplified layout view of a liquid crystal display of a second embodiment according to the present invention;

6A and 6B are cross-sectional views of a liquid crystal display according to a second exemplary embodiment of the present invention, which is taken along the line VI-VI 'of FIG. 5, in which no voltage is applied and no voltage is applied thereto. Represents the arrangement of liquid crystal molecules,

7A to 7F are cross-sectional views illustrating a method of manufacturing a color filter substrate of a liquid crystal display according to a second exemplary embodiment of the present invention in a process sequence;

8 is a simplified layout view of a liquid crystal display of a third embodiment according to the present invention;                 

9A and 9B are cross-sectional views of a liquid crystal display device according to a third exemplary embodiment of the present invention, taken along the line VII-VII 'of FIG. 8, in a state where no voltage is applied and a voltage is applied, respectively. Represents an arrangement of liquid crystal molecules,

10 is a view showing the transmittance by thickness of the organic insulating film,

11A shows a first organic insulating film pattern of a third embodiment according to the present invention,

12 shows a second organic insulating film pattern of a third embodiment according to the present invention,

13 shows a third organic insulating film pattern of a third embodiment according to the present invention,

14 shows the fourth organic insulating film pattern of the third embodiment according to the present invention,

15 shows the fifth organic insulating film pattern of the third embodiment according to the present invention,

16 shows the sixth organic insulating film pattern of the third embodiment according to the present invention,

17 shows a seventh organic insulating film pattern of the third embodiment according to the present invention,

18 shows the eighth organic insulating film pattern of the third embodiment according to the present invention.

<Description of the symbols for the main parts of the drawings>

3; Liquid crystal 50; Organic insulating film

51; R organic insulating film pixel 52; G organic insulating pixel

53; B organic insulating film pixel 54; Organic Insulation Dots

58; Non-organic insulating film dot 110; First substrate

190; Pixel electrode 191; Pixel incision pattern

210; Second substrate 220a; External black matrix

220b; Internal black matrix 230; Color filter                 

250; Overcoat film 270; Reference electrode

271; Reference incision pattern 291; Groove of reference electrode

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device and a method for manufacturing the same, and more particularly, to a liquid crystal display device and a method for manufacturing the same having improved viewing angle and side visibility.

In general, a liquid crystal display device injects a liquid crystal material between an upper substrate on which a reference electrode and a color filter are formed, and a lower substrate on which a pixel electrode and a thin film transistor and the like are formed, and then the liquid crystal material is injected into the reference electrode and the pixel electrode. By applying different potentials to form an electric field to change the arrangement of the liquid crystal molecules, and through this to control the light transmittance is an apparatus that represents the image.

However, it is an important disadvantage that the liquid crystal display device has a bad viewing angle and side visibility. To overcome these disadvantages, various methods for widening the viewing angle have been developed. Among them, liquid crystal molecules are oriented vertically with respect to the upper and lower substrates, and a method of forming a constant incision pattern or protrusion on the pixel electrode and the reference electrode that is opposite to the upper and lower substrates. This is becoming potent.

In the method of forming the incision pattern, a incision pattern is formed on the pixel electrode and the reference electrode, respectively, and the viewing angle is secured by evenly dispersing the tilting direction of the liquid crystal in four directions by using a fringe field formed by these incision patterns. How to do it.

The protrusions are formed by forming protrusions on the pixel electrode and the reference electrode formed on the upper and lower substrates, respectively, to adjust the lying direction of the liquid crystal molecules using an electric field distorted by the protrusions.

On the other hand, the domain divided by the incision pattern or protrusion is divided into several types depending on the direction in which the liquid crystal lies down. Generally, one domain is divided into four domains, one for each of the four directions. In this case, when the angle formed between the lower substrate and the long axis of the liquid crystal lying obliquely is called a tilt angle, the inclination angles of the liquid crystal molecules in the different domains are the same for the same applied voltage, so that the compensation ratio of the optical properties of the domain is low so that side visibility is achieved. There is a problem.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to provide a liquid crystal display and a method of manufacturing the liquid crystal display having improved viewing angle and side visibility.

In order to achieve the above object, a liquid crystal display of the present invention includes a first substrate, a pixel electrode formed on the first substrate, an organic insulating film formed on a predetermined region of an upper surface of the pixel electrode, and the first substrate and the predetermined substrate. And a second substrate disposed spaced apart from each other, a black matrix formed on a bottom surface of the second substrate, a color filter and a reference electrode, and liquid crystal injected between the first substrate and the second substrate.

Further, the inclination angle of the long axis of the liquid crystal in the region where the organic insulating film is formed is different from the inclination angle of the long axis of the liquid crystal in the region where the organic insulating film is not formed.

When the liquid crystal has negative dielectric anisotropy, the inclination angle of the long axis of the liquid crystal in the region where the organic insulating film is formed is larger than the inclination angle of the long axis of the liquid crystal in the region where the organic insulating film is not formed.

In addition, pixel areas representing respective colors of R, G, and B of the pixel electrodes are referred to as R pixels, G pixels, and B pixels, respectively, and a single area consisting of the R, G, and B pixels is referred to as the pixel area. The organic insulating film dot and the organic insulating film dot are formed on the pixel electrode when the organic insulating film dot is a non-organic insulating film dot and the organic insulating film dot is formed in a predetermined region therein. Non-organic insulating film dots are formed in the same area.

Further, when the R pixel of the organic insulating film dot is an R organic insulating film, the G pixel of the organic insulating film dot is a G organic insulating pixel, and the B pixel of the organic insulating film dot is a B organic insulating film, the respective R and G 50% of the area of the B organic insulating film pixels is covered with the organic insulating film.

In addition, when the four regions in which the liquid crystals lie in different directions in the respective R, G, and B organic insulating layer pixels are referred to as the first, second, third, and fourth directions R, G, and B organic domains, the pixels The area between the first, second, third, and fourth direction R organic domains is the same on the electrode, and the area between the first, second, third, and fourth direction G organic domains is the same. The area | region between the said 1st, 2nd, 3rd, and 4th direction B organic domains is formed equally.

Further, an area between the first direction R organic domain, the first direction G organic domain, and the first direction R organic domain is equally formed on the pixel electrode, and the second direction R organic domain and the second direction G organic The area between the domain and the second direction R organic domain is formed to be the same, and the area between the third direction R organic domain, the third direction G organic domain and the third direction R organic domain is formed to be the same, and the fourth The area between the direction R organic domain, the 4th direction G organic domain, and the 4th direction R organic domain is formed equally.

Further, the organic insulating film dots and the non-organic insulating film dots are alternately formed along the horizontal direction.

Further, the organic insulating film dots and the non-organic insulating film dots are alternately formed along the vertical direction.

The organic insulating film dots are formed in the dots in four directions adjacent to the non-organic insulating film dots.

In addition, the organic insulating film is formed in the organic domain of the R, G, and B organic domains formed in any one of the said organic insulating film dots in the same direction.

In addition, the organic insulating film is formed on organic domains in any two directions of the first to fourth directional organic domains on the R and B organic insulating film pixels, and the organic insulating film is formed on the G organic insulating film pixels in the remaining two organic domains. It is formed in.                     

In addition, the thickness of the organic insulating layer is 3.0 μm or less, and the dielectric constant of the organic insulating layer is 1.5 to 7.5.

Hereinafter, a first embodiment according to the present invention will be described in detail with reference to the accompanying drawings.

1 is a simplified layout view of a liquid crystal display device of a first embodiment according to the present invention, and FIGS. 2A and 2B are cross-sectional views of a liquid crystal display device of a first embodiment according to the present invention, taken along the line II-II ′ of FIG. 1. A cross-sectional view showing the arrangement of liquid crystal molecules in a state where no voltage is applied and a state where voltage is applied, respectively, in a normally black mode.

As shown in FIGS. 2A and 2B, a transparent pixel electrode 190 is formed on a surface of the first substrate 110, and the pixel electrode 190 is indium-tin-oxide (ITO) or induin-zinc (IZO). -oxide), or a transparent conductive film. The pixel electrode 190 has a pixel cutout pattern 191 having a portion thereof removed. The second substrate 210 corresponds to the first substrate 110 to be spaced apart from the first substrate so as to face the first substrate 110.

The outer black matrix 220a and the inner black matrix 220b are formed on the bottom of the second substrate 210. The outer black matrix 220a is formed in a matrix to define the pixel region A, and the inner black matrix 220b is formed in a predetermined pattern in the pixel region A. FIG.

Color filters 230 such as R, G, and B are formed on the outer and inner black matrices 220a and 220b. At this time, the color filter 230 is removed at a portion overlapping with the internal black matrix 220b to expose the internal black matrix 220b. The external black matrix 220b is also exposed without being covered by the color filter 230 at the boundary between the colors. A portion of the color filter 230 overlaps with the outer and inner black matrices 220a and 220b to contact the outer and inner black matrices 220a and 220b, and most of the rest of the color filter 230 is the second substrate 210. Is in direct contact with

Transparent reference electrodes 270 are formed on the exposed external and internal black matrices 220a and 220b and the bottom of the color filter 230. Below the inner black matrix 220b, the reference electrode forms a groove 291. The organic insulating film 50 is formed in a predetermined region of the bottom surface of the reference electrode 270. As shown in FIGS. 1A and 1B, the organic insulating layer 50 is formed in a predetermined region B of one pixel region A, which is bounded by an external black matrix 220a. The organic insulating film 50 is formed to cover the groove 291 of the reference electrode 270 formed on the bottom surface of the internal black matrix 220b.

Liquid crystal molecules 3 having negative dielectric anisotropy are injected between the first substrate 110 and the second substrate 210.

As shown in FIG. 2A, when no voltage is applied between the pixel electrode 190 and the reference electrode 270, the liquid crystal molecules 3 are vertically arranged with respect to the surfaces of the two substrates 110 and 210.

As shown in FIG. 2B, when a voltage is applied to the pixel electrode 190 and the reference electrode 270, an electric field E is formed between the first and second substrates 110 and 210. In this case, due to the groove 291 of the reference electrode 270 formed at a position overlapping with the pixel cut pattern 191 of the pixel electrode 190 and the internal black matrix 220b, the electric field is divided into two substrates 110 and 210. It forms a fringe field in the form of a curve that is not completely perpendicular to) but has a slope. Since the liquid crystal molecules 3 having negative dielectric anisotropy tend to align in a direction perpendicular to the direction of the electric field, the liquid crystal molecules 3 have their long axes inclined with respect to the surfaces of the two substrates 110 and 210. Will be arranged. In this case, regions in which the inclination directions of the liquid crystal molecules 3 are reversed on both sides of the pixel incision pattern 191 and the groove 291 of the reference electrode are compensated for, and the optical characteristics of these regions are compensated for each other to provide a viewing angle. This widens. However, in the region B covered with the organic insulating film 50, the tilt angle formed by the long axis of the liquid crystal 3 lying obliquely with the first substrate 110 is β1 and the region C not covered with the organic insulating film 50. In the case where the tilt angle formed by the long axis of the liquid crystal 3 lying obliquely with the first substrate 110 is β2, the region B covered with the organic insulating film 50 and the organic insulating film are not covered. Between the regions C, the inclination angles β1 and β2 of the long axis of the liquid crystal 3 are different from each other.

It will be described in detail below.

Even if the same voltage is applied between the region B covered with the organic insulating film 50 and the region C not covered with the organic insulating film 50, a difference occurs in the strength of the electric field formed. For example, a stronger electric field is generated in the region C in which the organic insulating film 50 is not covered than in the region B in which the organic insulating film 50 is covered. This is because the voltage applied to the liquid crystal in the region where the organic insulating film 50 is present is lower than the voltage applied to the liquid crystal in the region where the organic insulating film 50 is not present because the voltage is distributed to the organic insulating film 50. Therefore, the liquid crystal in the region where the organic insulating film 50 is covered is slightly laid down by the weak electric field, and the liquid crystal in the region where the organic insulating film 50 is not covered is laid by the stronger electric field. Therefore, the inclination angle β1 of the long axis of the liquid crystal in the region where the organic insulating film 50 is covered is larger than the inclination angle β2 of the liquid crystal in the region where the organic insulating film 50 is not covered.

Since the inclination angles of the liquid crystal molecules are different between the region B covered with the organic insulating film 50 and the region C not covered with the organic insulating film 50, as shown in FIG. 2, an applied voltage (Voltage) The relationship curve of the transmittance with respect to, ie, the VT curve, is different from each other. Therefore, the optical characteristics of the two regions B and C are effectively compensated for each other, thereby widening the viewing angle. In this case, the dielectric constant of the organic insulating film is preferably between 1.5 and 7.5, and the thickness is preferably 3.0 μm or less. This is because a problem occurs in the transmittance when the thickness of the organic insulating film is 3.0 µm or more.

In addition, although the organic insulating film is covered with one of two regions in the drawing, the organic insulating film may be covered with at least one domain among a plurality of domains that divide one pixel region. That is, the organic insulating layer pattern is not limited to the form in the embodiment of the present invention, but may be applied to various pattern forms and arrangements for dividing the pixel into four regions, that is, four domains.

1 is a simplified layout view of a liquid crystal display according to the present invention.

As illustrated in FIG. 1, the pixel cut pattern 191 and the groove 291 of the reference electrode are alternately formed. Here, since the groove 291 and the internal black matrix 220b of the reference electrode overlap, the same reference numerals are used in the layout view of FIG. 1. One pixel region A is divided into a region B in which the organic insulating layer 50 is covered and a region C in which the organic insulating layer 50 is not covered. Region B and region C are divided into a plurality of domains. The optical properties of these domains are compensated for each other, resulting in a wider viewing angle.

Next, a method of manufacturing the liquid crystal display according to the first exemplary embodiment of the present invention will be described in detail with reference to FIGS. 4A to 4D.

4A through 4D are cross-sectional views illustrating a method of manufacturing a color filter display panel of a liquid crystal display according to a first exemplary embodiment of the present invention, according to a process sequence.

The liquid crystal display includes a color filter display panel on which a reference electrode is formed, a thin film transistor array panel on which a pixel electrode is formed, and a liquid crystal injected between the color filter display panel and the thin film transistor array panel.

The manufacturing method of the color filter display panel 200 includes an internal and external black matrix and color filter forming step, a reference electrode forming step, an organic insulating film forming step, and an organic insulating film patterning step.

As shown in FIG. 4A, the inner and outer black matrix and color filter forming steps may be performed by forming an outer black matrix 220a having a mesh shape to cover the edge of the pixel area on the second substrate 210 and an inner black inside the pixel area. The matrix 220b is formed. Next, the process of coating, exposing and developing the photosensitive agent to which the pigment is added on the black matrices 220a and 220b is repeated three times to form red (R), green (G) and blue (B) color filters. At this time, the color filter 230 is also removed from the upper portion of the inner black matrix 220b positioned inside the pixel region so that the inner black matrix 220b is exposed.                     

Subsequently, as shown in FIG. 4B, the reference electrode forming step deposits an ITO or IZO film or the like on the exposed internal and external black matrices 220b and 220a and the color filter 230 to form the reference electrode 270. . In this case, the reference electrode 270 formed on the internal black matrix 220b is formed in the shape of the groove 291.

Subsequently, as shown in FIG. 4C, the organic insulating film forming step forms an organic insulating film 50 covering the reference electrode 270.

Subsequently, as shown in FIG. 4D, in the organic insulating film patterning step, the organic insulating film 50 is patterned to leave the organic insulating film 50 only in a part of a plurality of regions in the pixel region.

According to the manufacturing method of the color filter display panel, since the incision pattern is not formed on the reference electrode 270 formed on the second substrate, a photolithography process for forming the incision pattern, or to protect the color filter on the color filter from the etchant It is not necessary to form an overcoat film which is a buffer layer for the process, and the process is simplified. In addition, it is possible to solve the disadvantage that the resistance of the reference electrode 270 is increased when there is a cut pattern, it is possible to eliminate the defect caused by the over-etched or undercut the cut pattern.

FIG. 5 is a schematic layout view of a liquid crystal display of a second embodiment according to the present invention, and FIGS. 6A and 6B are cross-sectional views of a liquid crystal display of a second embodiment according to the present invention, along the line VI-VI 'of FIG. 5. It is sectional drawing shown, and shows the arrangement of the liquid crystal molecule in the state in which the voltage is not applied and the voltage in the normally black mode, respectively.                     

Here, the same reference numerals as in the above-described drawings indicate the same members having the same function.

6A and 6B, a transparent pixel electrode 190 is formed on the surface of the first substrate 110, and the pixel electrode 190 is indium-tin-oxide (ITO) or induin-zinc (IZO). -oxide), or a transparent conductive film. The pixel electrode 190 has a pixel cutout pattern 191 having a portion thereof removed. The second substrate 210 corresponds to the first substrate 110 to be spaced apart from the first substrate so as to face the first substrate 110.

The outer black matrix 220a and the inner black matrix 220b are formed on the bottom of the second substrate 210. The outer black matrix 220a is formed in a matrix to define the pixel region A, and the inner black matrix 220b is formed in a predetermined pattern in the pixel region A. FIG.

Color filters 230 such as R, G, and B are formed on the outer and inner black matrices 220a and 220b. At this time, the color filter 230 covers the internal black matrix 220b. The external black matrix 220b is exposed without being covered by the color filter 230 at the boundary between the colors. A part of the color filter 230 overlaps the external black matrix 220a and contacts the external black matrix 220a, and most of the color filter 230 directly contacts the second substrate 210.

An overcoat film 250 for protecting the color filter is formed on the bottom of the color filter 230. A transparent reference electrode 270 is formed on the bottom of the overcoat film 250. The reference incision pattern 271 is formed on the reference electrode 270. Here, the second substrate 210 and the first substrate 110 are alternately positioned so that the respective reference cut patterns 271 and the pixel cut patterns 191 do not correspond to each other.

The organic insulating layer 50 is formed in a predetermined region of the bottom surface of the reference electrode 270. As shown in FIGS. 6A and 6B, the organic insulating layer 50 is formed in a predetermined area B ′ of one pixel area A, which is bounded by the external black matrix 220a, thereby forming two pixel areas. Divide into areas The organic insulating layer 50 is formed so as not to cover the reference cut pattern 271 of the reference electrode 270.

Liquid crystal molecules 3 having negative dielectric anisotropy are injected between the first substrate 110 and the second substrate 210.

As shown in FIG. 6A, in the state where no voltage is applied between the pixel electrode 190 and the reference electrode 270, the liquid crystal molecules 3 are vertically arranged with respect to the surfaces of the two substrates 110 and 210.

As shown in FIG. 6B, when a voltage is applied to the pixel electrode 190 and the reference electrode 270, an electric field E is formed between the lower and second substrates 110 and 210. In this case, due to the pixel incision pattern 191 of the pixel electrode 190 and the reference incision pattern 192 of the reference electrode 270, the electric field is not formed completely perpendicular to the two substrates 110 and 210 and has a slope. It forms a fringe field in the form of a curve. Since the liquid crystal molecules 3 having negative dielectric anisotropy tend to align in a direction perpendicular to the direction of the electric field, the liquid crystal molecules 3 have their long axes inclined with respect to the surfaces of the two substrates 110 and 210. Will be arranged. In this case, regions in which the inclination directions of the liquid crystal molecules 3 are reversed are formed on both sides of the pixel incision pattern 191 and the reference incision pattern 192, and the optical characteristics of these regions are compensated to each other to widen the viewing angle. You lose. However, in the region B covered with the organic insulating film 50, the tilt angle formed by the long axis of the liquid crystal 3 lying obliquely with the first substrate 110 is β1 and the region C not covered with the organic insulating film 50. In the case where the tilt angle formed by the long axis of the liquid crystal 3 lying obliquely with the first substrate 110 is β2, the region B covered with the organic insulating film 50 and the organic insulating film are not covered. Between the regions C, the inclination angles β1 and β2 of the long axis of the liquid crystal 3 are different from each other.

It will be described in detail below.

Even if the same voltage is applied between the region B 'covered with the organic insulating film 50 and the region C' not covered with the organic insulating film 50, a difference occurs in the strength of the electric field formed. For example, a stronger electric field is generated in the region C 'which is not covered with the organic insulating film 50 as compared with the region B' which is covered with the organic insulating film 50. This is because the voltage applied to the liquid crystal in the region where the organic insulating film 50 is present is lower than the voltage applied to the liquid crystal in the region where the organic insulating film 50 is not present because the voltage is distributed to the organic insulating film 50. Therefore, the liquid crystal in the region where the organic insulating film 50 is covered is slightly laid down by the weak electric field, and the liquid crystal in the region where the organic insulating film 50 is not covered is laid by the stronger electric field. Therefore, the inclination angle β1 of the long axis of the liquid crystal in the region where the organic insulating film 50 is covered is larger than the inclination angle β2 of the liquid crystal in the region where the organic insulating film 50 is not covered.

Since the inclination angles of the liquid crystal molecules are different between the region B 'covered with the organic insulating film 50 and the region C' not covered with the organic insulating film 50, as shown in FIG. The relation curve of transmittance with respect to Voltage), that is, the VT curve, is different from each other. Therefore, the optical characteristics of the two regions B 'and C' are effectively compensated for each other, thereby widening the viewing angle. In this case, the dielectric constant of the organic insulating film is preferably between 1.5 and 7.5, and the thickness is preferably 3.0 μm or less. This is because a problem occurs in the transmittance when the thickness of the organic insulating film is 3.0 µm or more.

5, the pixel incision pattern 191 and the reference incision pattern 271 of the reference electrode are alternately arranged. Here, since the reference incision pattern 271 of the reference electrode and the internal black matrix 220b overlap, the same reference numerals are used in the layout view of FIG. 5. One pixel area A is divided into a region B 'covered with the organic insulating film 50 and a region C' not covered with the organic insulating film 50. The B 'region and the C' region are divided into a plurality of domains. The optical properties of these domains are compensated for each other to widen the viewing angle.

Next, a method of manufacturing the liquid crystal display of the present invention will be described in detail with reference to FIGS. 7A to 7D.

7A to 7D are cross-sectional views illustrating a method of manufacturing a color filter display panel of a liquid crystal display according to a second exemplary embodiment of the present invention, according to a process sequence.

The liquid crystal display includes a color filter display panel on which a reference electrode is formed, a thin film transistor substrate on which a pixel electrode is formed, and a liquid crystal injected between the color filter display panel and the thin film transistor substrate.                     

The manufacturing method of the color filter display panel 200 includes an internal and external black matrix and color filter forming step, an overcoat film forming step, a reference electrode forming step, an organic insulating film forming step, and an organic insulating film patterning step.

As shown in FIG. 7A, the inner and outer black matrix and color filter forming steps may be performed by forming an outer black matrix 220a having a mesh shape to cover the edges of the pixel area on the second substrate 210 and an inner black inside the pixel area. The matrix 220b is formed. Next, the process of coating, exposing and developing the photosensitive agent to which the pigment is added on the black matrices 220a and 220b is repeated three times to form red (R), green (G) and blue (B) color filters. That is, the color filter 230 covering the inner black matrix 220b is formed.

Subsequently, as shown in FIG. 7B, the overcoat film forming step may form an overcoat film 250 by depositing an ITO or IZO film or the like on the exposed external black matrix 220a and the color filter 230.

As illustrated in FIG. 7C, the reference electrode forming step covers the reference electrode 270 on the overcoat layer 250 and forms the reference cut pattern 271 at a position corresponding to the internal black matrix 220b. .

Subsequently, as shown in FIG. 7D, the organic insulating film forming step forms an organic insulating film 50 covering the reference electrode 270.

Subsequently, as shown in FIG. 7E, the organic insulating film patterning step is formed so as not to cover the reference cut pattern 271 of the reference electrode 270 by patterning the organic insulating film 50. In this case, the organic insulating film 50 is patterned to leave the organic insulating film only in a part of a plurality of areas in the pixel area.

FIG. 8 is a simplified layout view of the liquid crystal display device of the third embodiment according to the present invention, and FIGS. 9A and 9B are cross-sectional views of the liquid crystal display device of the third embodiment according to the present invention. A cross-sectional view of the liquid crystal molecules in a normally black mode and a voltage-free state and a voltage-applied state, respectively, are shown in the normally black mode.

9A and 9B, a transparent pixel electrode 190 is formed on a surface of the first substrate 110, and the pixel electrode 190 is indium-tin-oxide (ITO) or induin-zinc (IZO). -oxide), or a transparent conductive film. The pixel electrode 190 has a pixel cutout pattern 191 having a portion thereof removed. The organic insulating layer 50 is formed in a predetermined region of the upper surface of the pixel electrode 190. As shown in FIGS. 8, 9A, and 9B, the organic insulating layer 50 is formed in a predetermined region B of one pixel region A, which is bounded by the external black matrix 220a. The pixel area A is an area which generally shows one of R, G, and B colors. The organic insulating layer 50 is formed on the upper surface of the pixel electrode 190 without covering the pixel cut pattern 191 of the pixel electrode 190. The second substrate 210 corresponds to the first substrate 110 to be spaced apart from the first substrate 110 to face the first substrate 110.

The outer black matrix 220a and the inner black matrix 220b are formed on the bottom of the second substrate 210. The outer black matrix 220a is formed in a matrix to define the pixel region A, and the inner black matrix 220b is formed in a predetermined pattern in the pixel region A. FIG.

Color filters 230 such as R, G, and B are formed on the outer and inner black matrices 220a and 220b. At this time, the color filter 230 is removed at a portion overlapping with the internal black matrix 220b to expose the internal black matrix 220b. The external black matrix 220b is also exposed without being covered by the color filter 230 at the boundary between the colors. A portion of the color filter 230 overlaps with the outer and inner black matrices 220a and 220b to contact the outer and inner black matrices 220a and 220b, and most of the rest of the color filter 230 is the second substrate 210. Is in direct contact with

Transparent reference electrodes 270 are formed on the exposed external and internal black matrices 220a and 220b and the bottom of the color filter 230. Below the inner black matrix 220b, the reference electrode forms a groove 291.

Liquid crystal molecules 3 having negative dielectric anisotropy are injected between the first substrate 110 and the second substrate 210.

As shown in FIG. 9A, when no voltage is applied between the pixel electrode 190 and the reference electrode 270, the liquid crystal molecules 3 are vertically arranged with respect to the surfaces of the two substrates 110 and 210.

As shown in FIG. 9B, when a voltage is applied to the pixel electrode 190 and the reference electrode 270, an electric field E is formed between the second and second substrates 110 and 210. In this case, due to the groove 291 of the reference electrode 270 formed at a position overlapping with the pixel cut pattern 191 of the pixel electrode 190 and the internal black matrix 220b, the electric field is divided into two substrates 110 and 210. ), It forms a curved fringe field that is not entirely vertical but has a slope. Since the liquid crystal molecules 3 having negative dielectric anisotropy tend to align in a direction perpendicular to the direction of the electric field, the liquid crystal molecules 3 have their long axes inclined with respect to the surfaces of the two substrates 110 and 210. Will be arranged. In this case, regions in which the inclination directions of the liquid crystal molecules 3 are reversed on both sides of the pixel incision pattern 191 and the groove 291 of the reference electrode are compensated for, and the optical characteristics of these regions are compensated for each other to provide a viewing angle. This widens. However, in the region F not covered with the organic insulating film, the tilt angle formed by the long axis of the first substrate 110 and the liquid crystal 3 lying obliquely is β1 and the region D is covered with the organic insulating film 50. When the tilt angle formed by the long axis of the liquid crystal 3 lying obliquely on the first substrate 110 is β2, the region D covered with the organic insulating film 50 and the organic insulating film are not covered. Between the regions F, the inclination angles β1 and β2 of the long axis of the liquid crystal 3 are different from each other.

It will be described in detail below.

Even if the same voltage is applied between the region D covered with the organic insulating film 50 and the region F not covered with the organic insulating film 50, a difference occurs in the strength of the electric field formed. For example, a stronger electric field is generated in the region F in which the organic insulating film 50 is not covered than in the region D in which the organic insulating film 50 is covered. This is because the voltage applied to the liquid crystal in the region where the organic insulating film 50 is present is lower than the voltage applied to the liquid crystal in the region where the organic insulating film 50 is not present because the voltage is distributed to the organic insulating film 50. Therefore, the liquid crystal in the region covered with the organic insulating film 50 is laid down slightly by a weak electric field, and the liquid crystal in the region not covered with the organic insulating film 50 is laid down by a stronger electric field. Therefore, the inclination angle β2 of the long axis of the liquid crystal in the region where the organic insulating film 50 is covered is larger than the inclination angle β1 of the liquid crystal in the region where the organic insulating film 50 is not covered.

Since the inclination angles of the liquid crystal molecules are different between the region D covered with the organic insulating film 50 and the region F not covered with the organic insulating film 50, as shown in FIG. 2, an applied voltage (Voltage) The relationship curve of the transmittance with respect to, ie, the VT curve, is different from each other. Therefore, the optical characteristics of the two regions D and F are effectively compensated for each other, thereby widening the viewing angle. In this case, the dielectric constant of the organic insulating film is preferably between 1.5 and 7.5, and the thickness is preferably 3.0 μm or less. This is because a problem occurs in the transmittance when the thickness of the organic insulating film is 3.0 µm or more.

In addition, although the organic insulating film is covered with one of two regions in the drawing, the organic insulating film may be covered with at least one domain among a plurality of domains that divide one pixel region. That is, the organic insulating layer pattern is not limited to the form in the embodiment of the present invention, but may be applied to various pattern forms and arrangements for dividing the pixel into four regions, that is, four domains.

8 is a simplified layout view of a liquid crystal display according to the present invention.

As illustrated in FIG. 8, the pixel cut pattern 191 and the groove 291 of the reference electrode are alternately formed. Here, since the groove 291 and the internal black matrix 220b of the reference electrode overlap, the same reference numerals are used in the layout view of FIG. 8. One pixel area A is divided into a region D in which the organic insulating layer 50 is covered and a region F in which the organic insulating layer 50 is not covered. The D region and the F region are divided into a plurality of domains. The optical properties of these domains are compensated for each other, resulting in a wider viewing angle.

However, the viewing angle is improved by forming the organic insulating film 50 on the upper surface of the pixel electrode 190, but the luminance is reduced because the transmittance is inhibited. As shown in FIG. 10, the thicker the organic insulating layer 50 is, the lower the transmittance is. It is preferable that the thickness of the organic insulating film 50 is 3.0 micrometers or less.

Hereinafter, various embodiments in which an organic insulating film is formed in a predetermined region of the pixel electrode in order to increase luminance will be described.

11A to 18 show various organic insulating film patterns formed in predetermined regions of the pixel electrode.

Fig. 11A shows the first organic insulating film pattern of the third embodiment according to the present invention, and Fig. 12 shows the second organic insulating film pattern of the third embodiment according to the present invention.

As shown in FIG. 11A, the pixel regions A representing the colors of R, G, and B of the pixel electrodes 190 are respectively R pixels 51, 55, G pixels 52, 56, and B pixels. It is defined as (53, 57). Then, one region in which all of the R, G, and B pixels 51, 52, and 53 on which the organic insulating film is formed is gathered, and the R, G, and B pixels 55, 56, and 57 on which the organic insulating film is not formed. One area formed by gathering all of them is called dots 54 and 58. The organic insulating film 50 is a dot formed in a predetermined region inside the dot, and the organic insulating film dot 54 is a dot in which the organic insulating film 50 is not formed therein. do. R pixels of the organic insulating film dots 54 are R organic insulating film pixels 51, G pixels of the organic insulating film dots 54 are G organic insulating film pixels 52 and B pixels of the organic insulating film dots 54 are B pixels. It is defined as the organic insulating film pixel 53.

11A to 18 illustrate various organic insulation film patterns in which the organic insulation film dot 54 and the non-organic insulation film dot 55 are formed on the same area on the pixel electrode 190. As such, the organic insulating dot 54 and the non-organic insulating dot 55 formed on the pixel electrode 190 have the same area to prevent the organic insulating layer 50 from being formed in only a partial region, thereby preventing the luminance of the partial region from decreasing. To do this.

Then, 50% of the area of each of the R, G, and B organic insulating film pixels 51, 52, 53 is covered with the organic insulating film 50.

FIG. 11B is a simplified enlarged view of each of the R, G, and B organic insulating film pixels 51, 52, and 53 of FIG. 11A, showing the lying direction of the liquid crystal 3.

As shown in FIG. 11B, the directions in which the liquid crystals 3 lie in the R, G, and B organic insulating film pixels 51, 52, and 53 are different from each other.

For example, the R organic insulating layer 51 may be divided into first, second, third, and fourth directions of the R organic domains 51a, 51b, 51c, and 51d, which are four regions in which the liquid crystals 3 are laid down in different directions. have. Two pixel cutting patterns 191 are formed in the R organic insulating film 51. The upper right pixel cut pattern 191a having the upper right end of the pixel cut pattern and the upper left pixel cut pattern 191b having the upper left end of the pixel cut pattern are formed. In the first direction R organic domain 51a, the liquid crystal 3 is laid in the northwest direction based on the upper right pixel incision pattern 191a, and the second direction R organic domain 51b is based on the upper right pixel incision pattern 191a. As a result, the liquid crystal 3 is lying in the southeast direction. The liquid crystals 3 lie in the northeast direction with respect to the upper left pixel cut pattern 191b in the third direction R organic domain 51c, and the upper left pixel cut patterns 191a in the fourth direction R organic domain 51d. On the basis of the reference, the liquid crystal 3 is laid in the southwest direction.

Similarly, the G organic insulating pixel 52 may be divided into the first, second, third and fourth directions of the G organic domains 52a, 52b, 52c, and 52d, which are four regions in which the liquid crystals 3 are laid down in different directions. The B organic insulating layer 53 may also be divided into first, second, third, and fourth direction B organic domains 53a, 53b, 53c, and 53d, which are four regions in which the liquid crystals 3 are laid down in different directions. .

The first direction R organic domain 51a, the second direction R organic domain 51b, the third direction R organic domain 51c, and the fourth direction R organic domain 51d occupy all the pixel electrodes 190. The organic insulating film 50 is formed so that the areas may be the same. The first, second, third and fourth direction G organic domains 52a, 52b, 52c, 52d and the first, second, third and fourth direction B organic domains 53a, 53b, 53c, 53d are also shown. It is the same.

Further, the organic insulating film (ie, the first direction R organic domain 51a, the first direction G organic domain 52a, and the first direction B organic domain 53a occupy the same area on the entire pixel electrode 190). 50) is formed. The same applies to the R, G, and B organic domains in the second, third, and fourth directions.

Hereinafter, various organic insulating film patterns which satisfy such conditions will be described.

11A to 14 illustrate an organic insulating pattern of a line reversal type. The organic insulator pattern of the line inversion type refers to a form in which the organic insulator dot 54 and the non-organic insulator dot 55 are alternately formed in a line along the horizontal direction and the vertical direction.

As shown in FIGS. 11A and 12, the organic insulating film dots 54 and the non-organic insulating film dots 55 are alternately formed along the horizontal direction. In the following description, N is defined as referring to the first odd column or row, N + 1 to the second odd column or row, M to the first even column or row, and M + 1 to refer to the second even column or row. Organic insulating film dots 54 are formed in the Nth column and the N + 1th column, and non-organic insulating film dots 55 are formed in the Mth column and the M + 1th column. In the following, the Nth column and the Mth row are denoted by N-M.

As shown in FIG. 11A, the first organic insulating layer pattern includes N-M and N + 1-N organic insulating layer dots 54 in the first and second directional organic domains of the R, G, and B organic insulating layer pixels. The organic insulating film 50 is formed at (51a, 51b, 52a, 52b, 53a, 53b), and the third and fourth directional organic materials are formed on the organic insulating film dots 54 of the N-N and N + 1-M. The organic insulating film 50 is formed in the domains 51c, 51d, 52c, 52d, 53c, 53d.

12, the third and fourth directional organic domains 51c, 51d, 52c, 52d, 53c, and 53d are formed in the organic insulating film dots 54 of the N-N and N + 1-N. The organic insulating film 50 is formed in the first and second directional organic domains 51a, 51b, 52a, 52b, 53a, 53b in the organic insulating dot 54 of the N-M and N + 1-M. The organic insulating film pattern in which the organic insulating film 50 is formed is also possible.                     

Fig. 13 shows a third organic insulating film pattern of the third embodiment according to the present invention, and Fig. 14 shows a fourth organic insulating film pattern of the third embodiment according to the present invention.

As shown in FIGS. 13 and 14, the organic insulating film dots 54 and the non-organic insulating film dots 55 are alternately formed along the vertical direction.

15 to 18, an organic insulating pattern of dot inversion is formed.

The organic insulator film pattern of a dot inversion type means the form in which the organic insulator film dot 54 is formed in four directions which adjoin the non-organic insulation film dot 55. In other words, the non-organic insulation film dot 55 is formed in four directions adjacent to the organic insulation film dot 54.

Fig. 15 shows a fifth organic insulating film pattern of the third embodiment according to the present invention, and Fig. 16 shows a sixth organic insulating film pattern of the third embodiment according to the present invention.

As shown in Figs. 15 and 16, non-organic insulating film dots 55 are formed in the four directions of dots adjacent to the organic insulating film dots 54. Figs. The R organic domains 51a, 51b, 51c, 51d, G organic domains 52a, 52b, 52c, 52d, and B organic domains 53a, 53b formed in any one of the organic insulating film dots 54 are formed. , 53c and 53d are formed with the organic insulating film 50 in the organic domain in the same direction.

In detail, as shown in FIG. 15, the organic insulating film dots 54 are formed in four directions adjacent to the N + 1 -M non-organic insulating film dots 55. That is, the organic insulating film dot 54 is formed in N + 1-N, N + 1-N + 1, M-M, and M + 1-M. In the N + 1-N organic insulating film dots 54, both the R organic insulating pixel 51, the G organic insulating pixel 52 and the B organic insulating pixel 53 are formed in the first and second directional organic domains 51a. The organic insulating film 50 is formed at, 51b, 52a, 52b, 53a, 53b. In the fifth organic insulating layer pattern illustrated in FIG. 15, the organic insulating layer 50 is formed such that the organic domains formed in four dots having the square shape have the same number of organic domains in the first to fourth directions. That is, in the square shape K consisting of four dots of N-N, M-N, and N-M and M-M, the organic insulating dots of the N-N are arranged in the third and fourth directions. The organic insulating film 50 is formed in the R, G, and B organic domains 51c, 51d, 52c, 52d, 53c, and 53d, and R in the first and second directions is formed in the organic insulating film dots of the M-M. The organic insulating film 50 is formed in the G and B organic domains 51a, 51b, 52a, 52b, 53a, 53b. Therefore, the number of organic domains in the first to fourth directions included in the four dots is equal to each other.

In the case of the sixth organic insulating layer pattern illustrated in FIG. 16, the organic insulating layer 50 is formed such that the number of organic domains in the first to fourth directions included in the eight dots having a rectangular shape is the same. . That is, N-N, M-N, N-M, M-M, N + 1-N, M + 1-N, N + 1-M and In the rectangular form of eight dots of M + 1-M, the organic insulating film dots of the N-N and M-M have R, G, B organic domains 51c, 51d, 52c, 52d in the third and fourth directions. , 53c and 53d are formed with an organic insulating film 50, and the organic insulating film dots N + 1-N and M + 1 -M are R, G, B organic domains 51a in the first and second directions. The organic insulating film 50 is formed at, 51b, 52a, 52b, 53a, 53b. Accordingly, the number of organic domains in the first to fourth directions included in the eight dots is the same.

17 shows the seventh organic insulating film pattern of the third embodiment according to the present invention, and FIG. 16 shows the eighth organic insulating film pattern of the third embodiment according to the present invention.

As shown in Figs. 17 and 18, non-organic insulating film dots 55 are formed in the dots in four directions adjacent to the organic insulating film dots 54. Figs. In the organic insulating film dot 54, organic domains in any two directions of the first to fourth directional organic domains are disposed on the R and B organic insulating pixel pixels 51 and 53, and the remaining two on the G organic insulating film pixel 52. The organic domain of the direction is arrange | positioned.

In detail, the organic insulating layer 50 is formed such that the organic domains formed on the four dots having a square shape in the seventh organic insulating pattern shown in FIG. 17 are formed to have the same number of organic domains in the first to fourth directions. have. That is, in the square shape K consisting of four dots of N-N, M-N, and N-M and M-M, the organic insulating dots of the N-N are arranged in the third and fourth directions. The organic insulating film 50 is formed in the R and B organic domains 51c, 51d, 53c, 53d and the G organic domains 52a, 52b in the first and second directions, and the organic insulating film dots of the M-M The organic insulating film 50 is formed in the R and B organic domains 51a, 51b, 53a, 53b in the first and second directions and the G organic domains 52c, 52d in the third and fourth directions. Therefore, the organic domains formed in the four dots are all formed with the same number of organic domains in the first to fourth directions.

In addition, the organic insulating layer 50 is formed such that the organic domains formed in the eight dots having a rectangular shape in the eighth organic insulating pattern shown in FIG. 18 are formed to have the same number of organic domains in the first to fourth directions. That is, N-N, M-N, N-M, M-M, N + 1-N, M + 1-N, N + 1-M and In the rectangular form of eight dots of M + 1-M, the organic insulating film dots of the N-N and M-M have R, B organic domains 51c, 51d, 53c, 53d in the third and fourth directions, and The organic insulating film 50 is formed in the G organic domains 52a and 52b in the first and second directions, and the organic insulating film dots of the N + 1-N and M + 1 -M first and second directions, respectively. The organic insulating film 50 is formed in the R, B organic domains 51a, 51b, 53a, 53b and the G organic domains 52a, 52b in the third and fourth directions. Therefore, the number of organic domains formed in the eight dots is the same as the number of organic domains in the first to fourth directions.

 Although the present invention has been described with reference to one embodiment shown in the accompanying drawings, this is merely exemplary, and it will be understood by those skilled in the art that various modifications and equivalent other embodiments are possible. Could be. Accordingly, the true scope of protection of the invention should be defined only by the appended claims.

The liquid crystal display and the method of manufacturing the same according to the present invention weaken the intensity of the electric field by forming an organic insulating film in a predetermined portion in the pixel region, thereby forming a plurality of regions having different transmittances for the same voltage in the same pixel region. Since the side visibility of the liquid crystal display device can be improved.

In addition, by forming the organic insulating film in a line inversion form or in a dot inversion form, the organic insulating film can be formed while blocking the pixel electrodes as little as possible, thereby preventing a decrease in luminance caused by the organic insulating film.

Claims (14)

First substrate, A pixel electrode formed on the first substrate, An organic insulating film formed on a predetermined region of the upper surface of the pixel electrode; A second substrate positioned above the first substrate and spaced apart from the first substrate by a predetermined distance; A black matrix, a color filter, and a reference electrode formed on the bottom surface of the second substrate; First domain dividing means positioned on any one of the first and second insulating substrates, Second domain dividing means positioned on one of the first and second insulating substrates and dividing the pixel electrode into a plurality of domains together with the first domain dividing means; A liquid crystal injected between the first substrate and the second substrate, And the plurality of domains include an organic domain in which the organic insulating layer is formed and a non-organic domain in which the organic insulating layer is not formed. In claim 1, The inclination angle of the long axis of the liquid crystal in the region where the organic insulating film is formed is different from the inclination angle of the long axis of the liquid crystal in the region where the organic insulating film is not formed. In claim 2, And the inclination angle of the long axis of the liquid crystal in the region where the organic insulating film is formed is larger than the inclination angle of the long axis of the liquid crystal in the region where the organic insulating film is not formed, when the liquid crystal has negative dielectric anisotropy. In claim 3, Among the pixel electrodes, pixel regions representing respective colors of R, G, and B are called R pixels, G pixels, and B pixels, respectively, and a single region consisting of the R, G, and B pixels is dotted. When the dot formed in the predetermined region therein is an organic insulating film dot and a dot in which the organic insulating film is not formed therein is a non-organic insulating film dot, the organic insulating film dot and the non-organic material are formed on the pixel electrode. A liquid crystal display device in which insulating film dots are formed in the same area. In claim 4, When the R pixel of the organic insulation film dot is an R organic insulation film, the G pixel of the organic insulation film dot is a G organic insulation pixel, and the B pixel of the organic insulation film dot is a B organic insulation film, the respective R, G, B A liquid crystal display device wherein 50% of an area of an organic insulating film pixel is covered with the organic insulating film. In claim 5, In each of the R, G, and B organic insulating pixels, four regions in which the liquid crystals lie in different directions are referred to as the first, second, third, and fourth directions of the R, G, and B organic domains. The area between the first, second, third, and fourth direction R organic domains is the same, and the area between the first, second, third, and fourth direction G organic domains is the same. And an area between the first, second, third, and fourth direction B organic domains is the same. In claim 6, The area between the first direction R organic domain, the first direction G organic domain, and the first direction B organic domain is equally formed on the pixel electrode, and the second direction R organic domain, the second direction G organic domain, The area | region between 2nd direction B organic domains is the same, the area | region between the said 3rd direction R organic domain, the 3rd direction G organic domain, and the 3rd direction B organic domain is formed equally, and the said 4th direction R A liquid crystal display device having the same area between the organic domain, the fourth direction G organic domain, and the fourth direction B organic domain. The method according to any one of claims 5 to 7, A liquid crystal display device in which the organic insulating film dots and the non-organic insulating film dots are alternately formed along a horizontal direction. The method according to any one of claims 5 to 7, A liquid crystal display device in which the organic insulating film dots and the non-organic insulating film dots are alternately formed along a vertical direction. The method according to any one of claims 5 to 7, And the organic insulating film dot are formed in four directions of dots adjacent to the non-organic insulating film dot. In claim 10, The R, G, and B organic domains formed in any one of the organic insulating film dots have an organic insulating film formed in organic domains in the same direction. In claim 10, The organic insulating film is formed on organic domains in any two directions of the first to fourth directional organic domains on the R and B organic insulating film pixels, and the organic insulating film is formed on the organic domains of the remaining two directions on the G organic insulating film pixels. Liquid crystal display device. The method according to any one of claims 1 to 7, The organic insulating film has a thickness of 3.0 μm or less. The word of any of claims 1 to 7, wherein A liquid crystal display device having a dielectric constant of 1.5 to 7.5.

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