JPS6377018A - Reflection type color liquid crystal panel - Google Patents

Abstract

PURPOSE:To improve display quality by forming a metallic reflection film which has an area for one picture element and in common use as one electrode corresponding to plural active elements on one substrate, forming an anodically oxidized film thereon and constituting a color filter of such two-layered films. CONSTITUTION:The active element 6-1 and the metallic reflection film 3-1 in common use as the display electrode having the unit area of one picture element are formed on one glass substrate 1-1. The active element 6-1 is constituted of a gate electrode 6-1-1, drain electrode 6-1-2 and source electrode 6-1-3. The source electrode 6-1-3 and the active element 3-1 are connected and the anodically oxidized film 4-1 of the anodized thin transparent film is formed on the metallic reflection film 3-1. The two layers of the anodically oxidized film 4-1 and the metallic reflection film 3-1 are formed by using an anodic oxidation method. The wavelength region of the reflected light to be reflected from the metallic reflection film 3-1 by changing the film thickness of the thin transparent film 4-1 in the process of forming said layers. The colors of the color filter are eventually selected by the film thickness. The high-quality panel which is free from display defects by dust and obviates the change of the color of the color display with lapse of time is obtd.

Description

[Detailed Description of the Invention] [Summary] This invention provides a color filter used in a reflective color liquid crystal panel formed on a glass substrate in order to prevent deterioration of display quality due to dust adhesion or change in color over time. The color filter is composed of a two-layer structure consisting of a metal reflective film that also serves as an electrode and an anodic oxide film.

(Industrial Application Field) The present invention relates to a reflective color liquid crystal panel, and more particularly to a reflective color liquid crystal panel with an improved color filter structure.

A reflective color liquid crystal panel is provided with a color filter corresponding to each pixel. This color filter is produced by coloring pixel-corresponding regions of a glass substrate using pigments or dyes as colorants. Therefore, it is easy for dust to adhere during this coloring process, and the color tone of the colorant changes when used for a long time, and it no longer fulfills its function as a color filter, resulting in a decline in the quality of the reflective color LCD panel. Therefore, there is a need for a reflective color liquid crystal panel that does not have the above-mentioned drawbacks.

[Conventional technology]

A conventional reflective color liquid crystal panel is constructed as shown in FIG. That is, in the reflective color liquid crystal panel, a plurality of metal reflective films 3-1 to 3-n, which also serve as display electrodes each having a unit area of a pixel, are formed on the surface of one glass substrate 1-1. On the other glass substrate 1-2, a color filter 7 having the same dimensions as the metal reflective film is formed at a position opposite to the metal reflective film, and a common electrode 2 made of a transparent thin film layer is formed on the filter 7.

The liquid crystal 5 is sealed in the space between the common electrode 2 and the metal reflective films 3-1 to 3-n.

The incident light that has passed through the glass substrate 1-2 passes through the color filter 7, the common electrode 2, and the liquid crystal 5, and then reaches the metal reflective film 3-1.
The reflected light travels a course opposite to the above-mentioned course and is emitted to the outside of the glass substrate 1-2.

In this conventional color filter 7, gelatin is coated on the glass substrate 1-2, and organic dyes are printed on the gelatin at positions facing each metal reflective film using an electrodeposition method. A color filter is formed by attaching a dye.

Three organic dyes are used: red, blue, and yellow.

Therefore, for example, the light that has passed through the red pixel unit is colored red and is emitted from the glass substrate 1-2.

[Problem that the invention seeks to solve]

In conventional reflective color liquid crystal panels, color filters are fabricated using organic dyes, so the organic dyes discolor over time and dust may adhere to the panels during fabrication. Therefore, a high-quality, high-yield reflective color liquid crystal panel cannot be obtained, and furthermore, since the color filter is manufactured in a separate process, the process is complicated and not easy.

The object of the present invention is to provide a reflective color liquid crystal panel that is easy to manufacture under the above-mentioned conventional circumstances and has high display quality.

[Means for solving problems]

In this invention, for example, a metal reflective film that also serves as an electrode is formed on one glass substrate on which an active element is formed,
Furthermore, a transparent anodic oxide thin film is formed on this metal reflective film, and a color filter is constructed by a two-layer structure with this anodic oxide thin film.

[Effect]

The reflected light that passes through the liquid crystal and is reflected on the surface of the transparent anodic oxide film and the reflected light that is reflected on the metal reflective film cause a light interference phenomenon. In addition, the anodic oxide film changes the reflection wavelength range of light from the metal reflective film depending on the film thickness, and as a result, for example, red,
It emits light in three colors, blue and yellow, and acts as a color filter. Furthermore, this anodic oxidation thin film does not deteriorate over time and does not attract dust during the process, so display quality does not deteriorate. Furthermore, since the metal reflective film constituting the color filter also serves as an electrode, the manufacturing process of the panel is simplified and the yield is improved.

〔Example〕

FIG. 1 is a sectional view of a main part showing an embodiment of the present invention, in which an active element 6-1, for example, is placed on one glass substrate 1-1.
A metal reflective l! which also serves as a display electrode has a unit area of 1 and 1 pixel! It! 3-1 is formed. The active element 6-1 has a gate electrode 6-1-1 and a drain electrode 6.
-1-2 and a source electrode 6-1-3.

This source electrode 6-1-3 and metal reflective film 3-1 are connected. A transparent thin anodic oxide film 4-1 is formed on this metal reflective film 3-1. The two layers, the anodic oxide film 4-1 and the metal reflective film 3-1, are formed using an anodic oxidation method. By changing the thickness of the transparent thin film 4-1 during this formation process, the wavelength range of the reflected light reflected from the metal reflective film 3-1 is changed.

That is, the color of the color filter is selected depending on the film thickness.

In the glass substrate 1-2, the common electrode 2 is formed of a transparent conductive thin film as in the conventional case.

〔effect〕

As is clear from the above description, according to the present invention, there are no display defects due to dust, the color display does not change over time, is high quality, and is easy to manufacture, and exhibits extremely useful effects.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a main part showing an embodiment of the present invention, and FIG. 2 is a sectional view of a main part showing the structure of a conventional reflective color liquid crystal panel. In the figure, 1-1 and 1-2 are glass substrates, 2 is a common electrode, 3-1 to 3-n are metal reflective films, 4-1 to 4-n are transparent anodic oxide films, 5 is a liquid crystal, and 6 -1 to 6-n indicate active elements. Figure 1 m2 kyou

Claims (1)

[Claims] A liquid crystal (5) is sealed between two glass substrates (1-1, 1-2) arranged oppositely, and one glass substrate (1-1)
A plurality of active elements (6-1 to 6-n
), a display electrode, and a common electrode (2) on the liquid crystal sealing surface of the other glass substrate (1-2), wherein one of the substrates (1-1) has a plurality of A metal reflective film (3-1 to 3-n) serving as one electrode having an area of one pixel is formed corresponding to the active element, and an anodic oxide film (4-1 to 4-n) is formed thereon. A reflective color liquid crystal panel characterized in that a color filter is formed by forming a two-layer film.