JPH0611709A - Color liquid crystal display device - Google Patents

Abstract

PURPOSE:To eliminate a display defect so as to improve reliability and to obtain a good display grade by providing color filters having an electrical conductivity on a counter substrate. CONSTITUTION:This liquid crystal display device has a display electrode substrate 5 disposed with plural pixel electrodes 2 and the counter substrate 11 disposed with the color filters 7 having the electrical conductivity in the positions opposite to the pixel electrodes 2. A liquid crystal 12 is sealed by a sealing material 13 between the two substrates 5 and 11. The liquid crystal layer is changed to a light transmittable state by impressing a voltage between the pixel electrodes 2 and the color filters 7 opposite thereto to allow the transmission of light from a back light source 16, by which the color display melting the color tones of the color filters 7 is executed. Namely, the base material of the color filters 7 is provided with the electrical conductivity and since a transparent conductive film which is heretofore formed atop the color filters is not used, the display defect based thereon is eliminated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color liquid crystal display device.

[0002]

2. Description of the Related Art As shown in FIG. 3, a color liquid crystal display device includes a display electrode substrate 5 on which a plurality of picture element electrodes 2 are arranged,
A counter substrate 11 having a color filter 7 and a counter electrode 9 disposed at a position facing each pixel electrode 2 is provided, and a liquid crystal 12 is sealed between both substrates 5 and 11 by a seal member 13. .

Further, a backlight light source 16 is arranged on the side of the display electrode substrate 5, and constitutes a color liquid crystal display device as a whole.

The display electrode substrate 5 is based on the transparent insulating substrate 1, and a plurality of transparent pixel electrodes 2 are formed on the surface of the transparent insulating substrate 1. An alignment film 4 is formed over the entire surface of the substrate so as to cover the transparent pixel electrode 2, and a deflection plate 14 is provided on the surface of the transparent insulating substrate 1 opposite to the surface on which the alignment film 4 is formed. Has been formed.

The other counter substrate 11 is a transparent insulating substrate 6 serving as a base, and a color made of acrylic resin at a position facing each transparent pixel electrode 2 on the transparent insulating substrate 1 described above. Each filter 7 is formed.
A light-shielding film 8 also made of acrylic resin is provided in the gap between the adjacent color filters 7, and the color filter 7 and the light-shielding film 8 are covered to form a transparent conductive material such as ITO (Indium Tin Oxide) over the entire substrate. A counter electrode 9 made of a flexible film is formed. This counter electrode 9
The alignment film 10 is formed on the entire surface of the substrate, and the transparent insulating substrate 6 opposite to the surface on which the alignment film 10 is formed.
A deflection plate 15 is provided on the surface of the.

In the above color liquid crystal display device, when a voltage is selectively applied between each picture element electrode 2 and a counter electrode 9 facing the picture element electrode 2, the liquid crystal layer of the portion sandwiched between the two electrodes 2 and 9 is formed. The optical properties of 12 change. That is, the liquid crystal layer 12 in this portion is changed to a light transmissive state, the white light emitted from the backlight light source 16 is transmitted, and color display according to the color tone of the corresponding color filter 7 is performed.

[0007]

In the configuration of FIG. 3,
As a counter electrode 9 facing the transparent pixel electrode 2, ITO (Indium) is formed on the entire surface of the substrate so as to cover each color filter 7.
The transparent counter electrode 9 is formed by forming a transparent conductive film such as Tin Oxide).

Since the transparent conductive film is formed so as to cover each color filter 7, a defect such as step breakage of the transparent conductive film due to an edge defect of the color filter 7 occurs, and the transparent conductive film is also formed. If there is a film formation defect of the transparent film itself, there is a problem that the alignment of the liquid crystal around that part is disturbed and light leakage occurs, or a group bright spot defect occurs and the display quality is impaired.

SUMMARY OF THE INVENTION The present invention has been made to solve the problems of the prior art, and an object thereof is to improve the reliability of the color liquid crystal display device and to provide a color liquid crystal display device having a good display quality.

[0010]

In a color liquid crystal display device of the present invention, a display electrode substrate having a plurality of transparent pixel electrodes provided on an insulating substrate and the display electrode substrate are opposed to each other with a liquid crystal layer interposed therebetween. A counter substrate which has a conductive color filter at a position facing the transparent pixel electrode, and a voltage is applied between the color filter and the transparent pixel electrode facing the transparent pixel electrode. Then, the above object is achieved by changing the optical characteristics of the liquid crystal phase during this period.

[0011]

According to the present invention, a voltage is applied between each transparent pixel electrode and the opposing color filter, and the liquid crystal layer at the corresponding position is changed to a state in which light can pass therethrough. By transmitting the light, color display is performed according to the color tone of the corresponding color filter.

[0012]

EXAMPLE As shown in FIG. 1, an active matrix type color liquid crystal display device taken up in this example has a display electrode substrate 5 on which a plurality of picture element electrodes 2 are arranged and a position facing each picture element electrode 2. Has a counter substrate 11 on which a color filter 7 is arranged, and a liquid crystal 12 is sealed between the substrates 5 and 11 by a seal member 13.

Further, a backlight light source 16 is arranged on the side of the display electrode substrate 5 and constitutes a color liquid crystal display device as a whole.

As shown in FIG. 2, the display electrode substrate 5 includes a gate bus line 18 and a source bus line 17 which are three-dimensionally intersected with each other at right angles on the transparent insulating substrate 1. An insulating film 19 is formed at the intersection of 18. A transparent pixel electrode 2 is formed in each region surrounded by the bus lines 17 and 18 so as to substantially fill this region. Each of the pixel electrodes 2 has a thin film transistor 3 (hereinafter referred to as a TFT) as a switching element. Will be abbreviated). The source electrode 20 of the TFT 3 is connected to the source bus line 17, the gate electrode 21 is connected to the gate bus line 18, and the drain electrode 22 is connected to the transparent pixel electrode 2, and signals are exchanged between them.

An alignment film 4 is formed over the entire surface of the substrate so as to cover the transparent pixel electrode 2 and the TFT 3, and a deflector plate is provided on the surface of the transparent insulating substrate 1 opposite to the surface on which the alignment film 4 is formed. 14 is formed.

As shown in FIG. 1, the other counter substrate 11 is provided on the transparent insulating substrate 6 serving as a base at a position facing each transparent pixel electrode 2 on the transparent insulating substrate 1. A color filter 7 is formed on each. A light-shielding film 8 is formed in a space between adjacent color filters 7 so as to fill the gap.

Color filter 7 and light-shielding film 8 of this embodiment
Are highly transparent and highly conductive, such as polyvinyl alcohol (PVA) and polymethylmethacrylate (PMM).
The polymer alloy of A) is used as a base material, R (red), G (green), and B (blue) pigments are dispersed in the three color filters, and a black resin such as carbon is dispersed in the light-shielding film 8. , Is formed by a photolithography method.

Oxide-based electron conductive glass may be used as the conductive base material for the color filter 7.

The oxide type electron conductive glass includes vanadium pentoxide-barium oxide-diphosphorus pentaoxide and vanadium pentoxide-barium oxide.

The color filter 7 and the light shielding film 8 are directly covered with the alignment film 10.

Although the alignment film 10 is formed over the entire surface of the substrate, a deflecting plate 15 is formed on the surface of the transparent insulating substrate 6 opposite to the surface on which the alignment film 10 is formed.

The substrates 5 and 11 are arranged such that the alignment film 4 of the display electrode substrate 5 and the alignment film 10 of the counter substrate 11 face each other, and a liquid crystal is sealed by a seal member 13 between the substrates 5 and 11. ing.

Further, a backlight light source 16 is arranged on the side of the display electrode substrate 5 where the deflection substrate 14 is provided, and constitutes an active matrix type color liquid crystal display device as a whole.

In the above active matrix type color liquid crystal display device, each TFT 3 is selectively switched, and a voltage is selectively applied between each pixel electrode 2 corresponding thereto and the color filter 7 facing it. Then, the optical characteristics of the liquid crystal layer 12 between the electrodes 2 and 7 change. That is, the liquid crystal layer 12 in this portion is changed to a light transmissive state, the white light emitted from the backlight light source 16 is transmitted, and color display according to the color tone of the corresponding color filter 7 is performed.

[0025]

As described above, according to the present invention, since the conductive polymer or the conductive glass is used as the base material of the color filter and the transparent conductive film which is conventionally formed on the upper surface of the color filter is not formed, this transparent It is possible to provide a color liquid crystal display device in which display defects due to the conductive film are eliminated, the reliability of the substrate is improved, and the display quality is good.

Further, since the number of manufacturing steps is reduced by one, the cost can be reduced.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of an active matrix type liquid crystal display device in this example.

FIG. 2 is a schematic configuration of a display electrode substrate of an active matrix type color liquid crystal display device.

FIG. 3 is a sectional view of an active matrix type liquid crystal display device in a conventional example.

[Explanation of symbols]

 1, 6 transparent insulating substrate 2 transparent pixel electrode 3 thin film transistor (TFT) 4, 10 alignment film 5 display electrode substrate 7 color filter 8 light-shielding film 9 transparent counter electrode 11 counter substrate 12 liquid crystal layer 13 seal member 14, 15 deflection plate 16 backlight light source 17 source bus line 18 gate bus line 19 insulating film 20 source electrode 21 gate electrode 22 drain electrode

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Mikio Katayama 22-22 Nagaike-cho, Abeno-ku, Osaka-shi, Osaka Inside Sharp Corporation

Claims (1)

[Claims] 1. A display electrode substrate having a plurality of transparent picture element electrodes provided on an insulating substrate, and a counter substrate facing the display electrode substrate with a liquid crystal layer interposed therebetween. A color filter having conductivity is provided at a position facing the transparent pixel electrode, and a voltage is applied between the color filter and the facing transparent pixel electrode to change the optical characteristics of the liquid crystal layer therebetween. Characteristic color liquid crystal display device.