KR20120011294A - Liquid Crystal Display device - Google Patents

Abstract

PURPOSE: A liquid crystal display apparatus is provided to improve the reliability of a product by effectively controlling an interval between common electrodes within pixels arranged in an edge unit. CONSTITUTION: An LCD(Liquid Crystal Display) is formed to round shape structure. A gate driving unit operates plural gate lines. A data driving unit operates plural data lines. The boundary of a display area is formed to a round surface by the LCD panel. Pixels are arranged according to a curvature. The pixels include common electrodes(300a, 300c) which include a different interval each other.

Description

Liquid crystal display device

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device, and more particularly, to a liquid crystal display device which can improve product reliability by minimizing step defects occurring at an edge of a display area in a non-square type liquid crystal display device.

Display devices used in a computer monitor or a TV include organic light emitting display (OLED), field emission display (FED), and plasma display device (PDP). Pla includes a liquid crystal display (LCD) which does not emit light by itself and requires a light source.

In general, a liquid crystal display includes two substrates having a field generating electrode and a liquid crystal layer having dielectric anisotropt formed therebetween. A voltage is applied to the field generating electrode to generate an electric field in the liquid crystal layer, and the voltage is changed to adjust the intensity of the electric field to adjust the transmittance of light passing through the liquid crystal layer to display a desired image.

The liquid crystal display includes a data driver which receives image data from an external source and generates and supplies a data signal of a corresponding pixel to a data line of a liquid crystal display panel, and generates a gate signal to drive pixels of the liquid crystal display panel by one line. And a gate driver for supplying light and a backlight unit disposed on a rear surface of the liquid crystal display panel to provide light.

Recently, light emitting diodes having advantages such as light efficiency, thinning, and low power consumption have been widely used as a light source of a backlight unit. In general, a small liquid crystal display has a rectangular display screen. Therefore, the shape of the liquid crystal display panel is also rectangular.

Recently, a liquid crystal display device is used as a display device of various fields such as a watch or an instrument panel of a vehicle, and a circular display screen is required. Accordingly, the liquid crystal display panel has a circular structure.

In the liquid crystal display device having such a circular structure, a display area for displaying a screen and a non-display area for not displaying the screen also have a circular shape. In this case, pixels of the same size having a rectangular shape are arranged in a matrix to form a circular structure in the display area.

Since the number of pixels of the same size arranged in a matrix form per line does not change linearly in a circular LCD, the pixel arrangement is arranged in a step shape irregularly and at the boundary between the display area and the non-display area. A stepped defect will occur.

The step shape defects can be sufficiently visually checked by the user, thereby lowering the reliability of the product.

According to the present invention, liquid crystals can be improved in reliability of products by minimizing step defects by differently adjusting the spacing of common electrodes included in pixels positioned at the boundary between the display area and the non-display area of a circular LCD. It is an object to provide a display device.

According to an exemplary embodiment of the present invention, a liquid crystal display device includes a liquid crystal display panel having a circular structure and divided into a display area for displaying an image and a non-display area for not displaying an image, a gate driver for driving the plurality of gate lines, and And a data driver for driving a plurality of data lines, wherein an edge of the display area is formed of curved surfaces having different curvatures by the circular liquid crystal display panel, and pixels arranged according to the curvatures have a plurality of common intervals. Electrodes.

The liquid crystal display according to the present invention minimizes the step defect generated at the edge part by adjusting the intervals of the common electrodes included in the pixels disposed at the edge part of the display area according to the curvature. The reliability of the product can be improved.

1 is a view showing a liquid crystal display device according to an embodiment of the present invention.
FIG. 2 is a plan view schematically illustrating the liquid crystal display panel of FIG. 1.
FIG. 3A is a diagram illustrating I in detail of FIG. 2, and FIG. 3B is a diagram showing pixels of an edge part of FIG. 3A.

Hereinafter, embodiments according to the present invention will be described with reference to the accompanying drawings.

1 is a view showing a liquid crystal display device according to an embodiment of the present invention.

As shown in FIG. 1, the liquid crystal display according to the exemplary embodiment of the present invention is disposed on the liquid crystal display panel 210 on which an image is displayed and on the rear surface of the liquid crystal display panel 210. And a backlight unit 220 for providing light.

Upper and lower polarizing plates 101 and lower polarizing plates 102 may be attached to upper and lower surfaces of the liquid crystal display panel 210 so that optical axes are perpendicular to each other.

The liquid crystal display panel 210 includes a thin film transistor array substrate, a color filter substrate attached to face the thin film transistor array substrate, and a liquid crystal layer formed between the two substrates.

The thin film transistor array substrate includes a plurality of pixels in a matrix form, and each of the plurality of pixels extends in a first direction and extends in a second direction perpendicular to the first direction to insulate the gate line. And an intersecting data line and a pixel electrode. In addition, a thin film transistor (TFT) is formed in each pixel and is connected to the gate line, the data line, and the pixel electrode.

An RGB pixel as a color filter is formed on the color filter substrate by a thin film process, and a common electrode facing the pixel electrode is formed. Therefore, the liquid crystal layer is arranged by voltages applied to the pixel electrode and the common electrode, thereby adjusting the transmittance of light provided from the backlight unit 220.

The liquid crystal display panel 210 has a circular shape with respect to the display surface and includes a rectangular structure protruding on one side.

The backlight unit 220 positioned below the liquid crystal display panel 210 may include a support main 280 made of a mold having an upper surface, a light source unit 250 disposed on one side of the support main 280, and And a light guide plate 260 disposed in parallel with the light source unit 250, and optical sheets 230 disposed on the light guide plate 260.

The optical sheets 230 diffuse and condense the light incident from the light guide plate 260 and emit the light toward the liquid crystal display panel 210. The optical sheets 230 are formed in a round shape.

The light guide plate 260 converts point light into surface light, and converts point light incident from the light source unit 250 disposed on one side of the support main 280 into surface light to the liquid crystal display panel 210. Guide. In this case, the light guide plate 260 is formed in a circular shape.

The light source unit 250 may include a flexible printed circuit board (FPC) 253 and a plurality of light emitting diodes 251 mounted on a lower surface of the flexible circuit board 253. The flexible circuit board 253 is a circuit board on which a complex circuit is formed on a flexible insulating film, and is a substrate using a heat resistant plastic film such as PET (Polyelster) or PI (Polyimide).

The support main 28 is formed of a mold having an upper surface opened, and all regions except the region corresponding to the light source unit 250 are formed in a circular shape.

The support main 280 has the light guide plate 260, the optical sheets 230, and the light source 250 housed therein, and a plurality of support mains 280 inside the support main 280 corresponding to the light source unit 250. A plurality of receiving grooves 251a in which the light emitting diodes 251 are accommodated are formed.

The light blocking tape 200 is provided on the backlight unit 220 having such a structure.

The light blocking tape 200 corresponds to an area corresponding to the light source unit 250 of the backlight unit 220 and an edge of the support main 280, and the optical sheets 230 and the light source unit 250. It serves to fix to the support main (280).

In addition, the light blocking tape 200 serves to fix the backlight unit 220 and the liquid crystal display panel 210 by applying an adhesive to both surfaces thereof, and the light emitted from the backlight unit 220 is entirely made of black. To prevent leakage.

A lower polarizing plate 102 for transmitting only specific light among light incident from the backlight unit 220 is attached to a lower surface of the liquid crystal display panel 210. In addition, an upper polarizer 101 may be attached to an upper surface of the liquid crystal display panel 210 to transmit only specific light in the light traveling in the upper direction of the liquid crystal display panel 210.

The liquid crystal display panel 210 is divided into a display area for displaying an image and a non-display area in which the display area is positioned at an edge and does not display an image. A gate driver that provides a scan signal to the gate line of the liquid crystal display panel 210 may be located in the non-display area.

FIG. 2 is a plan view schematically illustrating the liquid crystal display panel of FIG. 1.

1 and 2, the liquid crystal display panel 210 includes a display area 201 in which an image is displayed and a non-display area 203 located at an edge of the display area 201 and in which no image is displayed. ).

A plurality of pixels are disposed in the non-display area 203 similarly to the display area 201. In particular, a plurality of pixels are also disposed at an edge portion that is a boundary between the display area 201 and the non-display area 203.

The pixels include a pixel electrode supplied with a data voltage provided to a data line of the liquid crystal display panel 210 of FIG. 1, and a common electrode facing the pixel electrode. For example, when the liquid crystal display panel 210 is in the IPS mode, the pixel electrode and the common electrode are formed on the thin film transistor array substrate of the liquid crystal display panel 210.

Each of the pixels adjusts light transmittance by a data voltage provided to the pixel electrode and a transverse electric field generated by the common voltage provided to the common electrode.

The common electrodes of the pixels in the display area 201 are formed to have the same interval and be spaced apart from each other by a predetermined interval. In contrast, the common electrodes of the pixels disposed in the non-display area 203 have different intervals according to the curvature of the edge portion.

FIG. 3A is a diagram illustrating I in detail of FIG. 2, and FIG. 3B is a diagram showing pixels of an edge part of FIG. 3A.

As shown in FIG. 3A, a plurality of pixels are disposed at an edge portion that is a boundary between the display area 201 of FIG. 2 and the non-display area 203 of FIG. 2. The plurality of pixels disposed in the edge part includes a common electrode and a pixel electrode, respectively. In this case, intervals between the common electrodes provided in the pixels disposed on the edge portion are different from each other.

For example, the pixels disposed on the edge portion may be divided into first to third pixels (pixel1 to pixel3) as illustrated in FIG. 3B.

The first pixel pixel1 includes a pixel electrode 350 and a plurality of first common electrodes 300a facing the pixel electrode 350 at regular intervals. The interval between the first common electrodes 300a is a.

The second pixel pixel2 includes a pixel electrode 350 and a plurality of second common electrodes 300b facing the pixel electrode 350 at regular intervals. The interval between the second common electrodes 300b is b.

The third pixel pixel3 includes a pixel electrode 350 and a plurality of third common electrodes 300c facing the pixel electrode 350 at regular intervals. The interval between the third common electrodes 300c is c. In this case, the a to c have a different length from each other.

The spacing a of the first common electrodes 300a included in the first pixel pixel1 may include the second and third common electrodes 300b included in the second and third pixels pixel2 and pixel3. Narrower than the intervals b and c of 300c). An interval b of second common electrodes 300b included in the second pixel pixel2 is smaller than an interval c of third common electrodes 300c included in the third pixel pixel3. The gap c of the third common electrodes 300c included in the third pixel3 is the widest.

As the distance between the common electrodes included in the pixel increases, the transmittance of light increases. Accordingly, the light transmittance of the third pixel pixel3 having the largest distance c between the common electrodes 300c increases with respect to the first and second pixels pixel1.pixel2.

When the third pixel pixel3 having a high light transmittance is properly disposed in a portion where the step defect is badly generated at the edge portion, the gray scale level of the portion where the third pixel pixel3 is disposed is changed so that the stairs The defect phenomenon can be minimized. That is, when the third pixel pixel3 having the high light transmittance is disposed at an edge corresponding to a region having a small curvature, the gray scale level of the portion where the third pixel pixel3 is disposed is changed so that the step is poor. The phenomenon can be minimized.

The common electrodes provided in the first to third pixels pixel1 to pixel3 may be adjusted such that the distance between the common electrodes and the height (or length) of the common electrode are 8 μm. That is, when the interval between the first common electrodes 300a provided in the first pixel is 2.5 μm, the height of the first common electrode 300a itself may be adjusted to 5.5 μm.

In addition, when the interval between the second common electrodes 300b provided in the second pixel pixel2 is 3.5 μm, the height of the second common electrode 300b itself may be adjusted to 4.5 μm. Similarly, if the interval between the third common electrodes 300c provided in the third pixel pixel3 is 4.5 μm, the height of the common electrode 300c itself may be adjusted to 3.5 μm.

As such, when the spacing of the common electrodes of the pixels disposed in the edge portion is differently adjusted, the transmittance of light of the corresponding pixels is different, thereby adjusting the gray scale level of the edge portion to adjust the edge ( It is possible to minimize the step failure caused at the edge portion.

101: upper polarizer 102: lower polarizer
200: shading tape 201: display area
203: non-display area 210: liquid crystal display panel
215: black matrix 220: backlight unit
230: optical sheet 250: light source unit
251: light emitting diode 251a: receiving groove
253: flexible circuit board 260: light guide plate
280: support main 350: pixel electrode
300a to 300c: first to third common electrodes

Claims (5)

A liquid crystal display panel having a circular structure and divided into a display area for displaying an image and a non-display area for not displaying an image;
A gate driver for driving the plurality of gate lines; And
And a data driver for driving the plurality of data lines.
An edge of the display area is formed by a curved surface having different curvature by the circular liquid crystal display panel, and the pixels arranged according to the curvature include common electrodes having different intervals. The method according to claim 1,
And the common electrode is formed to have a different distance and height according to the curvature of the edge of the display area. The method according to claim 1,
And pixels arranged in the display area include common electrodes at equal intervals. The method of claim 2,
And the common electrode is adjusted differently according to the curvature so that the sum of the lengths and the intervals between the adjacent common electrodes is 8 占 퐉. The method of claim 2,
The pixels disposed on the edge of the display area increase in transmittance of light as the distance between the common electrodes included in the pixels increases.

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