JP2001027754A - Liquid crystal display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance display quality of a liquid crystal display device. SOLUTION: The liquid crystal display device 1 is provided with a transistor array substrate 2 comprising display elements each of which is composed of a transistor and a pixel electrode 10 placed in respective regions 8 partitioned with plural source wires and gate wires 6 arranged in a matrix, a filter substrate 3 equipped with a black matrix 13K provided with opening parts corresponding to the partitioned regions 8 and a color filter 13 having color elements 13G (13R, 13B) arranged so as to cover the opening parts and a liquid crystal 4 enclosed between the both substrates. In this case, on the filter substrate 3 the opening parts along the source wire are covered with the color elements with an identical color 13B, and at the same time, a groove 15 is formed which exposes the black matrix 13K along the boundary part of the color elements with an identical color.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device in which liquid crystal is sealed in a space between a transistor array substrate and a color filter substrate.

[0002]

2. Description of the Related Art As an arrangement of color elements (RGB) of a color filter used in a liquid crystal display device, a stripe arrangement, a mosaic arrangement, a delta (triangle) arrangement and the like are known. Products with high definition use a stripe arrangement, and products with low definition use a mosaic or delta arrangement. FIG. 4 is a cross-sectional view along a stripe direction of a conventional TFT type liquid crystal display device having a color filter of a stripe arrangement. As shown in FIG. 4, in the conventional liquid crystal display device, a space having a predetermined gap is formed between the transistor array substrate 100 and the color filter substrate 200, and the liquid crystal is sealed therein. The array substrate 100 has a thin film transistor (not shown) and a pixel electrode 102 connected thereto in a region defined by a gate wiring 101 and a source wiring (not shown) on a transparent substrate such as glass. The pixel electrode 102 is made of ITO
A part of which is located outside the partition area and on the gate wiring 101, a gate insulating film 103
Most of the interlayer insulating films 103 are located in the above-mentioned partitioned region and are arranged in a single layer or a multilayer.
Are stacked on top of each other. The filter substrate 200 has a color filter 201 and a counter electrode 202 covering the color filter 201 disposed on a transparent substrate such as glass. The color filter 201 includes RGB color elements, and these are arranged on the light-shielding black matrix 203 in a stripe shape.

[0003]

In a conventional liquid crystal display device, a stripe-shaped color element has a black matrix 20.
3, the projections 204 are formed on the surface of the color filter 201 so as to face the gate wiring and the source wiring and protrude downward. The presence of the projections 204 makes it difficult to stably hold the cell gap forming spacer on the source wiring and the gate wiring. In addition, the presence of the color elements on the black matrix 203 shortens the distance between the counter electrode 202 and the source wiring or the gate wiring, which causes a parasitic capacitance. In view of the above, an object of the present invention is to improve the display quality of a liquid crystal display device. Another object is to enhance display quality by stabilizing the cell gap. Another object is to reduce parasitic capacitance formed between a counter electrode and a source wiring or a gate wiring to prevent image quality deterioration due to the parasitic capacitance.

[0004]

According to the liquid crystal display device of the present invention, a region defined by a plurality of source wirings and gate wirings is arranged in a matrix, and a transistor is formed in the partitioned region. A transistor array substrate on which a display element composed of pixel electrodes is disposed, a filter substrate including a black matrix having an opening corresponding to the partition region and a color filter having a color element disposed so as to cover the opening, In a liquid crystal display device including a liquid crystal sealed between substrates, the filter substrate covers the opening along predetermined wiring with a color element of the same color, and the black matrix is exposed at a boundary between the color elements of the same color. The groove is formed.

According to a second aspect of the present invention, there is provided a liquid crystal display device in which a liquid crystal is sealed in a space between a transistor array substrate and a color filter substrate.
The transistor array substrate is configured by arranging a transistor and a pixel electrode in a region defined by a plurality of source wirings and gate wirings, and the color filter substrate includes a black matrix having openings corresponding to the defined regions. In a liquid crystal display device comprising a color filter in which color elements are arranged in a stripe shape so as to cover the filter element, the filter substrate has a groove of a predetermined depth formed at a boundary portion between color elements of the same color. Features.

According to a third aspect of the present invention, there is provided a liquid crystal display device in which a liquid crystal is sealed in a space between a transistor array substrate and a color filter substrate.
The transistor array substrate is configured such that transistors and pixel electrodes are directly arranged on a transparent substrate in a region defined by a source wiring and a gate wiring on a transparent substrate, and the color filter substrate is formed in the partitioned region. In a liquid crystal display device including a color filter in which color elements are arranged in a stripe shape so as to cover the openings of a black matrix having corresponding openings, the filter substrate has a groove at a boundary between color elements of the same color. It is characterized by forming.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings, taking a transmissive liquid crystal display device whose back surface is illuminated by a backlight as an example. 1 and 2 are cross-sectional views of the liquid crystal display device, and are cross-sectional views of portions corresponding to II and II-II in FIG. FIG. 3 is a plan view showing a schematic configuration of the transistor array substrate.

In the liquid crystal display device 1, a space having a predetermined gap is formed in a gap portion surrounded by a sealing material (not shown) between the transistor array substrate 2 and the color filter substrate 3, and the liquid crystal 4 is formed therein. Is enclosed.
An alignment film (not shown) of polyimide or the like is formed on opposing surfaces of the substrates 2 and 3. In this display device 1, external light is irradiated from the transistor array substrate 2 side to the filter substrate 3.

The array substrate 2 has a display element comprising a thin film transistor 9 and a pixel electrode 10 connected thereto in each of a plurality of regions 8 defined by a gate wiring 6 and a source wiring 7 on a transparent substrate 5 made of glass or the like. Have been placed. The pixel electrode 10 is formed of a transparent electrode such as ITO (indium tin oxide), and most of the pixel electrode 10 is located in the partition region 8 and is arranged so as to be in contact with the transparent substrate 5. As described above, since the pixel electrode 10 is formed directly on the transparent substrate 5 without the interposition of the interlayer insulating film such as the gate insulating film 11, the region 8 is recessed from its peripheral portion. Since light absorption by the interlayer insulating film is eliminated, light use efficiency can be improved. That is, if the output light of the backlight illumination device is the same, the surface luminance of the liquid crystal display device can be increased as compared with the conventional case. Further, if the surface luminance is kept the same, the power consumption of the lighting device can be reduced.

Since the display device 1 is of a type in which an auxiliary capacitance is formed using the gate wiring 6, the pixel electrode 1
0 is part of the gate line 6 to form an auxiliary capacitance.
The gate insulating film 11 is interposed between them.

The filter substrate 3 has a color filter 13 disposed on a transparent substrate 12 made of glass or the like, and a transparent counter electrode 14 made of ITO or the like disposed to cover the color filter 13.
The counter electrode 14 can be formed on the color filter 13 with a flattening film made of acrylic or the like interposed therebetween. However, if the flattening film is formed, the function of a groove 15 described later may be reduced. In the example, the counter electrode 14 is formed directly on the color filter 13. Color filter 13
Is to cover the opening of the black matrix 13K,
The RGB color elements 13R, 13G, 13B are connected to the source wiring 7
And stripes arranged in the same direction. The black matrix 13 </ b> K is formed of a light-shielding metal or resin, and has a plurality of openings having the same shape as the partition region 8. Each color element 13R, 13G, 13B is arranged in the opening of the black matrix 13K so that the periphery thereof is surrounded by the black matrix 13K. That is, a separation groove 15 is formed at each of the boundary between the color elements 13G, 13G of the same color and the boundary between the color elements 13R, 13G, 13B of different colors. Part is exposed. Therefore, the color elements 13R, 13G, 13G are located on the surface of the filter substrate 3 at positions facing the source wiring 7 and the gate wiring 6.
A groove 15 having a depth corresponding to the thickness of B is formed, and this groove 15 plays a role in regulating the movement of the spacer 16 for maintaining the cell gap.

Since the groove 15 also serves to increase the distance between the counter electrode 14 and the source wiring 7 or the gate wiring 6,
The parasitic capacitance around the transistor 9 can be reduced.

The isolation trenches 15 correspond to the cell gaps G1 of the source line 7 and the gate line 6 corresponding to the cell gaps G1 of the partition region 8 which have become slightly wider due to the removal of the interlayer insulating film 11, respectively. It also has the effect of expanding G3. Here, the depth of the groove 15 depends on the color elements 13R, 13R.
The thickness is set to be approximately the same as the thickness of each of the color elements 13R, 13G, and 13B by controlling the processing (etching processing and the like) for forming the groove 15. You can also. Thus, the groove 15
, The cell gaps G2 and G3 can be set to the same value as the cell gap G1 even if the cell gap G1 increases or decreases due to a change in the configuration of the array substrate 2 or the like.

As described above, the color elements 13G, 1 of the same color
3G is arranged in the same direction as the predetermined wiring (the source wiring 7 in this example) to form a striped arrangement, while the separation groove 15 is formed at the boundary between adjacent color elements of the same color.
Compared with the conventional stripe arrangement in which no groove is formed, the spacer 16 on the wiring (gate wiring 6) can be held more stably, and the cell gap can be kept constant.
Further, the parasitic capacitance along the wiring (the gate wiring 6 and the source wiring) can be reduced.

[0015]

As described above, according to the liquid crystal display of the present invention, the cell gap can be kept constant, and unnecessary parasitic capacitance can be reduced to improve display quality. In addition, the interlayer insulating film in the partition region can be removed, so that light can be effectively used.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view (a portion corresponding to II in FIG. 3) of an embodiment of the present invention.

FIG. 2 is a sectional view of an embodiment of the present invention (II-II in FIG. 3);
(Corresponding part).

FIG. 3 is a plan view of an array substrate according to one embodiment of the present invention.

FIG. 4 is a sectional view (corresponding to FIG. 1) of a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Liquid crystal display device 2 Transistor array substrate 3 Color filter substrate 4 Liquid crystal 5 Transparent substrate 6 Gate wiring 7 Source wiring 8 Partition area 9 Thin film transistor 10 Pixel electrode 11 Gate insulating film 12 Transparent substrate 13 Color filter 14 Counter electrode 15 Groove 16 Spacer

Continuation of the front page (72) Inventor Hidehito Kanazawa 3-201 Minamiyoshikata, Tottori-shi, Tottori Pref. Sanyo Electric Co., Ltd. (72) Inventor Taku Ikemoto 3-201 Minamiyoshikata, Tottori-shi, Tottori Pref. (72) Inventor Masayuki Kameya 3-201 Minamiyoshikata, Tottori City, Tottori Prefecture F-term (reference) 2H091 FA02Y FA35Y FA41Z FD22 GA06 GA07 GA08 GA13 LA16 2H092 HA28 JA24 MA17 NA01 NA23 PA02 PA03 PA08 PA09 PA13

Claims (3)

[Claims] 1. A transistor array substrate in which regions partitioned by a plurality of source wirings and gate wirings are arranged in a matrix, and a display element including a transistor and a pixel electrode is disposed in the partitioned region. A liquid crystal display device comprising: a filter substrate having a black matrix having a formed opening and a color filter having a color element arranged to cover the opening; and a liquid crystal sealed between the two substrates. A liquid crystal display device, wherein the same color element covers the opening along the line, and a groove for exposing the black matrix is formed at a boundary between the color elements of the same color. 2. A liquid crystal display device in which liquid crystal is sealed in a space between a transistor array substrate and a color filter substrate, wherein the transistor array substrate has a transistor and a pixel in an area defined by a plurality of source wirings and gate wirings. A liquid crystal display device comprising an electrode disposed thereon, and the color filter substrate comprising a color filter in which color elements are arranged in a stripe pattern so as to cover the opening of a black matrix having an opening corresponding to the partition region. 3. The liquid crystal display device according to claim 1, wherein the filter substrate has a groove having a predetermined depth at a boundary between color elements of the same color. 3. A liquid crystal display device in which liquid crystal is sealed in a space between a transistor array substrate and a color filter substrate, wherein the transistor array substrate has a transistor in a region defined by a source line and a gate line on a transparent substrate. And each of the pixel electrodes are arranged directly on a transparent substrate, and the color filter substrate is arranged with color elements in a stripe shape so as to cover the openings of a black matrix having openings corresponding to the partition areas. A liquid crystal display device comprising a color filter, wherein the filter substrate has a groove formed at a boundary between color elements of the same color.