KR20040107217A - Panel and liquid crystal display including the same - Google Patents

Abstract

PURPOSE: A display panel and a liquid crystal display device provided with the same are provided to prevent the leakage of light due to the misalignment of the liquid crystal alignment by forming the dividing portion and the protrusion on the same plane pattern. CONSTITUTION: A display panel includes an insulation substrate, a gate line(124), a gate insulation layer, a semiconductor layer(151), a pair of data lines(171,173), a drain electrode(175), a pixel electrode and a protrusion. The gate line is formed on the insulation substrate. The gate insulation layer covers the gate line. The semiconductor layer is formed on the gate insulation layer. The pair of data lines is crossing with the gate line and is provided with the source electrode contact to the semiconductor layer. The portion of the drain electrode is contact to the semiconductor layer. The pixel electrode is connected to the drain electrode and is provided with a plurality of the dividing portions. And, the protrusion is formed on the dividing portions.

Description

Display panel and liquid crystal display including same {Panel and liquid crystal display including the same}

The present invention relates to a display panel and a liquid crystal display including the same, and more particularly, to a display panel having a plurality of domain dividing means for obtaining a wide viewing angle and a liquid crystal display including the same.

Generally, a liquid crystal material is injected between a color filter display panel on which a common electrode and a color filter are formed, and a thin film transistor array panel on which a thin film transistor and a pixel electrode are formed. By applying different potentials to the electric field 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. At this time, a polarizing plate is provided above the color filter display panel and below the thin film transistor display panel, so that light transmittance is varied according to the polarization state of light passing through the liquid crystal layer.

As the liquid crystal filled between the color filter display panel and the thin film transistor array panel, a twisted nematic liquid crystal (TN) is generally used. The TN liquid crystal molecules have a long and thin rod shape, have a constant pitch, twist in a spiral shape, and have a twisted structure in which the alignment direction of the long axis of the liquid crystal molecules is continuously changed.

In a liquid crystal display using a twisted nematic liquid crystal, the incident polarized light exhibits different optical viewing angles depending on the arrangement of the long and short axes of the molecules. Since the viewing angle of the liquid crystal display device is formed along the long axis of the liquid crystal molecules of the spiral structure, the long axis of the molecule changes according to the viewing angle. Such a liquid crystal display has a viewing angle symmetrical with respect to the horizontal direction and an asymmetric viewing angle with respect to the vertical direction. In particular, gray level phenomenon occurs in a direction in which the liquid crystal tilt direction and the viewing angle at the center of the cell coincide. Therefore, the light transmittance is distributed relatively symmetrically with respect to the horizontal viewing angle, but the light transmittance is distributed asymmetrically with respect to the up and down directions, so that an image inversion is generated at the viewing angle in the up and down directions, thereby narrowing the viewing angle.

As a method for overcoming this disadvantage, there is a method of vertically aligning the liquid crystal (VA). The vertical alignment mode makes it easy to obtain a wide viewing angle by symmetrically arranging liquid crystals through domain division and has a fast response characteristic. At this time, a cutout (or cutout pattern) or a protrusion is used as the domain dividing means.

The method of forming the cutout is a method of widening the viewing angle by forming cutouts in the pixel electrode and the common electrode, respectively, and adjusting the direction in which the liquid crystal molecules lie down using a fringe field formed by the cutouts. In the method of forming the protrusions, the protrusions are formed on the pixel electrode or the common electrode formed on the upper and lower display panels to adjust the lying direction of the liquid crystal molecules using an electric field distorted by the protrusions.

The greater the width of the incision, the greater the regulating power of the liquid crystal, but increasing the width decreases the aperture ratio and decreases the luminance. In the case of using the projections, there is a problem in that light leakage occurs around the projections due to weak regulation of the liquid crystals by the projections.

SUMMARY OF THE INVENTION The present invention has been made in an effort to provide a display panel capable of securing a regulating power of liquid crystal when a plurality of domains are formed, and a liquid crystal display including the same.

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

FIG. 2 is a cross-sectional view taken along the line II-II ′ of FIG. 1,

3 is a cross-sectional view taken along the line III-III ′ of FIG. 1,

4 is a layout view of a color filter display panel according to a first exemplary embodiment of the present invention;

5 is a layout view of a thin film transistor array panel according to a first exemplary embodiment of the present invention.

6 is a layout view of a liquid crystal display according to a second exemplary embodiment of the present invention.

7 is a cross-sectional view taken along the line VII-VII ′ of FIG. 6,

8 is a cross-sectional view taken along the line II-II ′ of FIG. 1 with the liquid crystal display according to the third exemplary embodiment of the present invention.

※ Explanation of code for main part of drawing ※

110, 210: insulated substrate 121, 124: gate line

140: gate insulating film 151: semiconductor layer

161, 165: ohmic contact layer

171, 173: data line 175: drain electrode

91, 92, 93, 271, 272, 273: incision

220: black matrix 230R, 230G, 230B: color filter

270: common electrode 280a, 280b: projection

In order to achieve the above object, the present invention divides and aligns the liquid crystal molecules into multiple domains by using a protrusion and an incision together.

Specifically, the display panel may include an insulating substrate, a gate line formed on the insulating substrate, a gate insulating film covering the gate line, a semiconductor layer formed on the gate insulating film, a data line intersecting the gate line, and having a source electrode in contact with the semiconductor layer, at least part of the display panel. The drain electrode includes a drain electrode formed in contact with the semiconductor layer and spaced apart from the source electrode by a predetermined distance, connected to the drain electrode, and having a plurality of cutouts in which predetermined regions are removed, and protrusions formed in the cutouts.

It is preferable to further include an ohmic contact layer formed between the data line and the drain electrode and the semiconductor layer.

At this time, the semiconductor layer is preferably formed along the data line.

The data line and the drain electrode are preferably formed in the same planar pattern as the ohmic contact layer, and the ohmic contact layer is preferably formed in the same plane pattern as the semiconductor layer except between the source electrode and the drain electrode.

In addition, it is preferable that the pixel electrode is divided into a plurality of small portions by the incision, and the small portions are electrically connected.

In accordance with another aspect of the present invention, a liquid crystal display device includes a first insulating substrate, a gate line formed on the first insulating substrate, a data line insulated from and intersecting the gate line, and defining a pixel area. A thin film transistor connected to a line, a pixel electrode formed in a pixel region and connected to the thin film transistor, the pixel electrode having a plurality of first cutouts from which a predetermined region is removed, a second insulating substrate facing the first insulating substrate, and facing the pixel electrode It is formed, and includes a common electrode having a plurality of second incision portion, a predetermined portion is removed, and projections formed in at least one of the first and second incision.

The black matrix may be formed on the first or second insulating substrate and may further include red, green, and blue color filters formed on the first or second insulating substrate and corresponding to the pixel region. .

In addition, it is preferable that the pixel electrode and the common electrode are divided into a plurality of small parts by the first and second cutouts, respectively, and the small parts are electrically connected, and the first and second cutouts do not overlap. desirable.

DETAILED DESCRIPTION Embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention.

In the drawings, the thickness of layers, films, panels, regions, etc., are exaggerated for clarity. Like parts are designated by like reference numerals throughout the specification. When a part of a layer, film, area, plate, etc. is over another part, this includes not only the part directly above the other part but also another part in the middle. In contrast, when a part is just above another part, it means that there is no other part in between.

Embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[First Embodiment]

1 is a layout view of a liquid crystal display according to an exemplary embodiment of the present invention, FIG. 2 is a cross-sectional view taken along the line II-II 'of FIG. 1, and FIG. 3 is a cross-sectional view taken along the line III-III' of FIG. 1. .

As shown in FIGS. 1 to 3, the liquid crystal display device has a structure in which a liquid crystal 3 is filled between the color filter display panel 200 and the thin film transistor array panel 100. The liquid crystal 3 has a predetermined pretilt according to the pattern of the pixel electrode 190 and the common electrode 270, and forms a plurality of domains according to the direction of the pretilt.

The color filter display panel 200 will be described in more detail with reference to FIGS. 2 to 4. 4 is a layout view of a color filter display panel according to an exemplary embodiment of the present invention.

As illustrated, the color filter display panel 200 has a black matrix 220 defining a pixel area in a matrix form on the transparent insulating substrate 210. Red, blue, and green color filters 230R, 230G, and 230B are formed on the pixel area. The red, green, and blue color filters 230R, 230G, and 230B have the same color in the column direction of the matrix, and red, green, and blue are alternately formed in the row.

An overcoat film 250 and a common electrode 270 are stacked on the entire substrate including the color filters 230R, 230G, and 230B. The overcoat film 250 is not essential to planarize the substrate and prevent the pigments of the color filters 230R, 230G, and 230B from diffusing to the common electrode 270.

The common electrode 270 has cutouts 271, 272, and 273, and the cutouts 271, 272, and 273 respectively have diagonal cutouts 91 and 93 of the pixel electrode 190 to be described later. Formed. In this case, the cutouts 271, 272, and 273 of the common electrode 270 include diagonal portions parallel to the diagonal cutouts 91 and 93 of the pixel electrode 190, and a refraction portion overlapping the sides of the pixel electrode. The refraction portion has a longitudinal refraction portion and a horizontal refraction portion.

The projections 280b are formed in the cutouts 271, 272, and 273, and the alignment layer 21 is formed on the entire substrate including the projections 280b.

Next, the thin film transistor array panel will be described with reference to FIGS. 2, 3, and 5. 5 is a layout view of a thin film transistor array panel according to an exemplary embodiment of the present invention.

In the thin film transistor array panel 100, a gate line 121 extending in one direction is formed on the transparent lower insulating substrate 110. Here, one portion or branched portion of the gate line 121 is used as the gate electrode 124 of the thin film transistor. One end of the gate line 121 may be wider than the gate line 121 to receive a signal transmitted from a gate driving circuit (not shown).

The gate insulating layer 140 is formed on the gate line 121 to cover them. A semiconductor layer 151 made of amorphous silicon without doping impurities is formed in a predetermined region of the gate insulating layer 140. The semiconductor layer 151 is formed under a data line, which will be described later, and extends under the drain electrode 175.

In addition, ohmic contact layers 161 and 165 are formed on the semiconductor layer 151. The ohmic contacts 161 and 165 may include a linear portion 161 and an island portion 165. The island portion 165 is formed at a predetermined distance away from the linear portion 161, and they have the same planar pattern as the semiconductor layer 151 except for a predetermined region of the semiconductor layer 151. The predetermined region of the semiconductor layer 151 is a channel portion that forms a channel of the thin film transistor.

Data lines 171 are formed on the ohmic contacts 161 and 165 to cross the gate lines 121 and define pixel regions. The data line 171 is branched and has a source electrode 173 overlapping the gate electrode 124. In addition, a drain electrode 175 is formed on the ohmic contact layer 165 to face the source electrode at a predetermined distance and overlap the gate electrode 124. The data line 171 corresponds to the linear portion 161 of the ohmic contacts 161 and 165, and the drain electrode 175 corresponds to the island portion 165.

One end of the data line 171 may be wider than the width of the data line 171 to receive a signal transmitted from a data driving circuit (not shown).

The passivation layer 180 covering the semiconductor layer 151 is formed on the entire surface of the substrate including the data lines 171 and 173 and the drain electrode 175. The passivation layer 180 is provided with a contact hole 183 exposing the drain electrode 175. The pixel electrode 190 connected to the drain electrode 175 through the contact hole 183 is formed on the passivation layer 180.

In addition, the passivation layer 180 may have contact holes (not shown) that expose one end portion of the data line 171 and the gate line 121, respectively. In addition, the passivation layer 180 may include a contact auxiliary member (not shown) connected to one end of the data line 171 and the gate line 121 through a contact hole.

The pixel electrode 190 includes cutouts 91, 92, and 93 for forming a plurality of domains. In this case, the cutouts 91, 92, and 93 are diagonally disposed in the horizontal cutout 92 formed in the horizontal direction at the position that half-divides the pixel electrode 190 and the upper and lower portions of the half-divided pixel electrode 190, respectively. It has diagonal incisions 91 and 93 formed in this. At this time, the upper and lower diagonal cutouts 91 and 93 are perpendicular to each other. This is to evenly distribute the direction of the fringe field in four directions. The projections 280a are formed in the cutouts 91, 92, and 93, and the alignment film 11 is formed on the entire substrate including the projections 280a.

The cutouts 91, 92, 93, 271, 272, and 273 of the pixel electrode 190 and the common electrode 270 are formed to form a plurality of domains and may be modified in various forms.

As described above, when the cutouts 91, 92, 93, 271, 272, and 273 and the protrusions 280a and 280b for forming a plurality of domains are formed together, the fringe field is strongly formed to increase the regulating force of the liquid crystal. . Therefore, since the liquid crystal has a pretilt in a predetermined direction, it may have a fast response speed.

As such, by forming the cutouts 91, 92, 93, 271, 272, and 273 and the projections 280a and 280b together, the regulating force of the liquid crystal is increased. Therefore, even if the width of the cutouts 91, 92, 93, 271, 272, and 273 is narrow, the liquid crystal can be regulated to have a predetermined pretilt. In this way, the width of the cutout portion can be made narrow, so that the aperture ratio of the pixel can be improved, thereby increasing the luminance.

Second Embodiment

6 is a layout view of a liquid crystal display according to an exemplary embodiment of the present invention, and FIG. 7 is a cross-sectional view taken along the line VII-VII ′ of FIG. 6.

As shown, unlike the first embodiment, the data lines 171 and 173 and the drain electrode 175 and the ohmic contact layers 161 and 165 of the thin film transistor array panel have the same planar pattern. The ohmic contacts 161 and 165 have the same planar pattern except for a predetermined region of the semiconductor layer 151. The predetermined region is a channel portion that forms a channel of the semiconductor layer 151.

Third Embodiment

8 is a cross-sectional view of a liquid crystal display according to an exemplary embodiment of the present invention.

As shown, unlike the first and second embodiments, red, green, and blue color filters 230R, 230G, and 230B are formed on the thin film transistor array panel in the third embodiment.

Specifically, the thin film transistor array panel 100 has the gate line 121, the gate insulating layer 140, the semiconductor layer 151, the data line 171, and the drain electrode 175 on the substrate as in the first and second embodiments. ) Is formed. A passivation layer 801 formed of an inorganic material is formed on the semiconductor layer 151, and red, green, and blue color filters 230R, 230G, and 230B are formed on the passivation layer 801. An interlayer insulating film 802 is formed on the red, green, and blue color filters 230R, 230G, and 230B.

The pixel electrode 190 and the auxiliary contact members 81 and 82 are formed on the interlayer insulating layer 802 as in the first and second embodiments.

Next, the color filters 230R, 230G, and 230B and the overcoat layer 250 of the first and second embodiments are not formed on the color filter display panel 200, except that the portions are the same as those of the first and second embodiments. It is formed in a structure.

Although preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements of those skilled in the art using the basic concepts of the present invention defined in the following claims are also provided. It belongs to the scope of rights.

As described above, when the cutouts and the projections for forming a plurality of domains are formed together in the same planar pattern, the fringe field is strongly formed, and the regulating force of the liquid crystal increases. Accordingly, light leakage due to disorientation of the liquid crystal does not occur, and the liquid crystal can be aligned to have a predetermined pretilt even when the width of the cutout is narrow, thereby providing a liquid crystal display having high brightness.

Claims (9)

Insulation board, A gate line formed on the insulating substrate, A gate insulating film covering the gate line, A semiconductor layer formed on the gate insulating film, A data line intersecting the gate line and having a source electrode in contact with the semiconductor layer; At least a part of the drain electrode contacting the semiconductor layer and formed to face the source electrode at a predetermined distance, A pixel electrode connected to the drain electrode and having a plurality of cutouts from which a predetermined region is removed; Protrusions formed on the incision Display panel comprising a. In claim 1, The display panel further comprises an ohmic contact layer formed between the data line and the drain electrode and the semiconductor layer. In claim 2, The semiconductor layer is formed along the data line. In claim 3, The data line and the drain electrode are formed in the same planar pattern as the ohmic contact layer. And the ohmic contact layer is formed in the same planar pattern as the semiconductor layer except between the source electrode and the drain electrode. The method of claim 1 or 2, The pixel electrode is divided into a plurality of small portions by the cutout, and the small portions are electrically connected to each other. First insulating substrate, A gate line formed on the first insulating substrate, A data line insulated from and intersecting the gate line to define a pixel area; A thin film transistor connected to the gate line and the data line, A pixel electrode formed in the pixel region and connected to the thin film transistor, the pixel electrode having a plurality of first cutouts from which a predetermined region is removed; A second insulating substrate facing the first insulating substrate, A common electrode formed to face the pixel electrode and having a plurality of second cutouts from which predetermined portions are removed; And a projection formed on at least one of the first and second cutouts. In claim 6, A black matrix formed on the first or second insulating substrate and defining the pixel region; Red, green, and blue color filters formed on the first or second insulating substrate and corresponding to the pixel areas. Liquid crystal display further comprising. In claim 6 or 7, The pixel electrode and the common electrode are divided into a plurality of small portions by the first and second cutouts, respectively, and the small portions are electrically connected to each other. In claim 8, The first cutout and the second cutout do not overlap.