JPH01244426A - Reflection type liquid crystal display device - Google Patents

Abstract

PURPOSE:To prevent the advance of the light from a liquid crystal layer side through an insulating layer to the inside of an array and to eliminate the degradation in the contrast of a screen by forming an insulator having a high light absorption effect to the insulator layer between reflecting picture element electrodes and the reflecting picture element electrode adjacent thereto. CONSTITUTION:A voltage is impressed to the liquid crystal layer 16 when a thin-film transistor (TR) as a switching picture element and an auxiliary capacitor 13 turn on an current flows to the reflecting picture element electrode 15. The incident light from a counter glass substrate 18 side is reflected by the reflecting picture element electrode 15 at this time and is polarized during the passage through the liquid crystal layer 16. A difference in the contrast from the picture element by which the light is not polarized is then generated and an image is obtd. Since the black insulator PrMnO3 19 is provided on the insulating layer between the reflecting picture element electrodes 15, by sputtering the advance of the incident light to the inside of the thin-film TR 13 side is suppressed. The leak current by the photoconduction of the switching element 13 is, therefore, prevented and the degradation in the contrast of the screen is obviated.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a reflective liquid crystal display device having an active element for use in a B-I section display device.

BACKGROUND OF THE INVENTION In recent years, liquid crystal display devices using active elements have come to be used as television or information terminals.

A conventional reflective liquid crystal display device will be explained below.

FIG. 2 is a cross-sectional view of a conventional reflective liquid crystal display device, in which 1 is an insulating substrate, 2 is a wiring electrode, 3 is a switching element, 4 is an insulator layer, 5 is a reflective pixel electrode, 6 is a liquid crystal layer, and 7 is a cross-sectional view of a conventional reflective liquid crystal display device. 8 is a counter common electrode, 8 is a counter transparent substrate, and 9 is a blank bearer I.
It's lithox.

The operation of the reflective liquid crystal display device configured as follows will be described below.

First, when the switching element 3 is turned on, a current flows through the reflective pixel electrode 5. Due to the dirt, a voltage is applied to the liquid crystal layer 6 sandwiched between the reflective pixel electrode 5 and the opposing common electrode 7, and the liquid crystal operates. At this time, light for making the display easier to see is irradiated from the opposite transparent electrode side, and the incident light is reflected by the reflective pixel electrode 5. Here, the light is polarized when passing through the liquid crystal layer 6, and a difference in con I and las I occurs between the light and the pixels that are not polarized, and an image is obtained. Opposing transparent electrode substrate B
The upper black matrix 9 is used to hide color unevenness that occurs in areas other than the reflective pixel electrode 5 portion.

Problems to be Solved by the Invention However, in the conventional configuration described in item 1, since light enters the inside of the TPT from the liquid crystal layer side through the insulating layer between the reflective electrodes, the light acts on the switching element. Reduces the electrical resistance of the semiconductor layer that makes up the switching element (photoconduction). This has the disadvantage that the charge stored in the pixel electrode and the opposing common electrode leaks through the switching element, resulting in a change in the orientation of the liquid crystal, resulting in a decrease in ZI-last.

The present invention solves the problems of the conventional art as described above, and eliminates the decrease in contrast of a display screen, and also enables the formation of a silk matrix at the same time, thereby simplifying the process. The purpose of the present invention is to provide a type of liquid crystal display device.

Means for Solving the Problem In order to achieve this object, the reflective liquid crystal display device of the present invention has a light absorption coefficient that is provided in an insulating layer between a reflective pixel electrode and an adjacent reflective pixel electrode. Constructed from highly insulating material.

Function: This structure prevents incident light and reflected light from entering the array through the insulating layer between the reflective electrodes, and prevents leakage current caused by photoconduction of the switching elements. You can prevent the elements.

EXAMPLE An example of the present invention will be described below with reference to the drawings.

FIG. 1 shows a cross-sectional structure of a reflective liquid crystal display device according to an embodiment of the present invention. In Figure 1, 1
1 is a glass substrate as an insulating substrate, 12 is a wiring electrode, 13
14 is an amorphous silicon nitride film as an insulator layer, 15 is a reflective pixel electrode, 16 is a liquid crystal layer, and 17 is a counter common electrode, which are formed by sputtering. 1B is a glass substrate as a counter transparent substrate, 19 is a black insulator, and PrMn○ is formed by sputtering.
There are 3 membranes.

Further, an auxiliary capacitor is formed on the wiring electrode 12.

The operation of the reflective liquid crystal display device configured as described above is similar to that of a conventional device.

As shown in the following, according to this embodiment, by filling the insulating layer 2 between the reflective pixel electrodes with a black insulator PrMnO3, it is possible to suppress the light from entering the inside of the TFT side. Therefore, leakage current due to photoconduction of the switching element can be prevented.

In addition, by forming a black insulator between the reflective pixel electrodes of the TFT (!!lI substrate), the process of forming furasocmatrinox on the opposing transparent substrate can be reduced, and the array member between the TFT side substrate and the opposing transparent substrate can be reduced. (・ is no longer needed, and production 7
Simplification to the extent of L can be achieved.

Although an oxide called P r M n O3 was used as the black insulator, an organic material with high light absorption and good insulation properties may be used.

Effects of the Invention As described in J-, the present invention provides a reflective liquid crystal display device in which an insulator having a high light absorption effect is formed on an insulating layer between a reflective pixel electrode and an adjacent reflective pixel electrode. This prevents light from the liquid crystal layer side from entering the inside of the array through the insulating layer, and prevents leakage current due to a decrease in resistance of the switching element due to photoconduction. Furthermore, it is possible to eliminate the need for the flank mask formed on the transparent substrate side, greatly contributing to the simplification of the manufacturing process, and reducing production costs. Accordingly, it is possible to realize a reflective liquid crystal display device that can obtain effects.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a reflective liquid crystal display device according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view of a conventional reflective liquid crystal display device. 11...Crow board, 12. Wiring electrode, 13...
... T F T, 14 ... amorphous silicon nitride film layer,
15... Reflective pixel electrode, 16... Liquid crystal layer, 17
. . . Opposing common electrode, 18 . . . Opposing glass substrate, ]
9...P r M n O3 film layer.

Claims (4)

[Claims] (1) A substrate having a group of reflective pixel electrodes arranged in a matrix to display a liquid crystal and a group of switching elements for supplying signals to the reflective pixel electrodes, and a substrate having a set of reflective pixel electrodes arranged in a matrix to display a liquid crystal, and a substrate having a group of switching elements for supplying signals to the reflective pixel electrodes; and a substrate facing the substrate and having a common electrode, and a substrate having a light absorption coefficient provided on an insulating layer between the reflective pixel electrode and an adjacent reflective pixel electrode. A reflective liquid crystal display device characterized by having a high insulating material. (2) The reflective liquid crystal display device according to claim (1), wherein the switching element is formed of a thin film transistor, a diode, or a nonlinear switching element. (3) The reflective liquid crystal display device according to claim (2), wherein a plurality of switching elements are formed in each pixel. (4) The reflective liquid crystal display device according to claim (1), wherein an auxiliary capacitor is formed in each display pixel of the reflective pixel electrode group.