JPH04133022A - Liquid crystal display device - Google Patents

Abstract

PURPOSE:To execute multicolor display in which display quality is improved by forming a segment electrode in an interdigital shape, arranging a specified color filter on the electrode and providing a light shielding layer on a non- display area on a common electrode. CONSTITUTION:Each segment electrode 2 equivalent to a display area is formed in the interdigital shape by using electrodes 2a and 2b. Then, a color filter layer 5 for performing the multicolor display is formed on the segment electrode 2 formed in the interdigital shape. Meanwhile, a light shielding film 4 is formed on a non-display area on the common electrode 3 formed on a substrate 1b by using metal such as nickel and chrome. Thus, contrast is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION B) Industrial Field of Application The present invention relates to a liquid crystal display device, and more particularly to a liquid crystal display device in which transparent electrodes have an interdigital shape.

(b) Conventional technology Conventionally, liquid crystal display elements for displaying numbers using a segment method, in which switching between two or more display colors (hereinafter referred to as multicolor), have been performed using a dot matrix method or a general segment type liquid crystal display. A so-called interdigital method is known in which a common electrode of a display element is divided into a plurality of interdigital shapes.

The dot matrix type has problems such as complicated connections between drive circuit components and a plurality of lead wires, narrow operating margin, and lower display performance than segment type liquid crystal display elements. On the other hand, the interdigital type does not suffer from the above-mentioned problems and can provide a good multicolor display.

A multi-color liquid crystal display device using an interdigital method is described in, for example, Japanese Patent Laid-Open No. 136718 (GO2F 1/133), and a detailed description thereof will be omitted.

(c) Problems to be Solved by the Invention As mentioned above, the interdigital system is optimal for obtaining a good multicolor display. However, since the multi-color interdigital method described in the above-mentioned Japanese Patent Application Laid-Open No. 59-136718 uses an interdigital shape for the common electrode, the following problems occur.

That is, as described above, since the common electrode has an interdigital shape, its driving method is necessarily a driving method with a duty ratio or higher. As a result, (1) For example, if an interdigital shape is formed by dividing into two parts, the driving method becomes duty driving. It takes,
The driving method is such that a constant voltage is always applied to non-selected electrodes of the interdigital common electrode. Therefore,
When performing color display, as mentioned above, a certain voltage is not applied to the non-selected electrodes, so the color of the color filter on the non-selected electrodes is slightly blurred, resulting in a decrease in the contrast of the color display. be. This problem becomes more serious as the duty drive becomes higher.

■Because the common electrode has an interdigital shape,
An insulator such as an alignment film is placed in the divided regions of the common electrode divided into an interdigital shape, and a relatively large stray capacitance is generated between the divided regions. Due to this stray capacitance,
There is a problem in that the effective value ratio of the voltage applied to the selected electrode and the non-selected electrode of the common electrode changes, resulting in a significant decrease in display contrast.

■Because the common electrode has an interdigital shape,
When the display area is narrow or when multicolor display is to be improved, it is necessary to form the common electrode pattern extremely thin. As a result, the wiring resistance increases significantly, causing display unevenness, resulting in a problem of deterioration of display quality.

(d) Means for Solving the Problems The present invention has been made in view of the above-mentioned problems, and includes a pair of glass substrates disposed facing each other, a plurality of segment electrodes being formed on the inner surface of one of the glass substrates, In a liquid crystal display device in which a common electrode is formed on the inner surface of the other glass substrate and a desired segment display is performed, a plurality of segment electrodes completely formed on the one glass substrate are formed into an interdigital shape, and a common electrode is formed on the inner surface of the interdigital shape. A predetermined color filter is disposed on the common electrode, and a light shielding layer is disposed on the non-display area on the common electrode.

(E) Function As described above, according to the present invention, by forming the segment electrodes into an interdigital shape, it becomes possible to perform multicolor display using a static drive method, improving display contrast and providing multicolor display with a wide viewing angle. It is possible to realize a display device of.

Furthermore, in the present invention, since the segment electrodes have an interdigital shape as described above, even when forming an interdigital shape in each segment electrode, the pattern length of the routing line can be determined more easily than in the conventional interdigital LCD. It can be made significantly shorter.

Furthermore, since the color filters arranged on the interdigital electrodes are formed by electrodeposition, they can also be arranged on lead lines other than the interdigital electrodes, and the cell gap can be kept constant.

Furthermore, by disposing a metal light-shielding film in areas other than the non-display area, display durability can be improved.

(F) Example The liquid crystal display device of the present invention will be described below based on the example shown in FIGS. 1A to 2.

FIG. 1A is a plan view of a segment electrode substrate on which segment electrodes are formed, and FIG. 1B is a plan view of a common electrode substrate on which a common electrode has been formed and which has been disposed facing the segment electrode substrate. The common electrode is formed on the back side of the common electrode substrate.) FIG. 1C is a partially enlarged view of FIG. 1A, and FIG. 2 is a sectional view when the respective substrates are integrated.

1A to 2, (la) and (lb) are transparent substrates, (2) are segment electrodes formed on the substrate (1a), and (3) are common electrodes formed on the substrate (1b). electrode,
(4) is a light shielding film, and (5) is a color filter layer formed on the segment electrode (18).

A glass substrate is used as each of the transparent substrates (la) and (lb), and a transparent electrode of a desired shape for performing segment display is formed on the glass substrate using a transparent electrode material such as indium oxide.

On one transparent substrate (1a), as shown in FIG.
c) has been completely extended. That is, each segment electrode (2) corresponding to the display area is formed in an interdigital shape, forming a figure-eight pattern. This will be explained in further detail using FIG. 1C.

FIG. 1C is an enlarged view of the interdigital shape part of FIG. 1A, and in this example, two electrodes (2a) (2b)
is used to form interdigital. Note that the area indicated by the dotted line is an area where segment display is performed.

On the other hand, a common electrode (3) is formed on the other substrate (1b) as shown in FIG. 1B.The common electrode (3) formed in this example has a single structure for static driving. However, the common electrode (3) is not limited to a single structure, and may be divided into two or more parts.

Also, on the common electrode (3) there is a figure 8 segment, i.e.
A light shielding film (4) is formed using a metal such as nickel or chromium in a non-display area excluding the display area.

Incidentally, a color filter layer (5) for performing multicolor display is formed on segment electrodes (2) formed in an interdigital shape. More specifically, in the present invention, the color filter layer (5) is formed not only on the interdigital shaped portion of the segment electrode (2>) which becomes the display area, but also on the wiring line of the non-display area extending from the interdigital electrode. Actively formed.

That is, the thickness of the color filter layer (5) is approximately 1.5 to 2.
0μ, whereas the transparent electrode of the segment and common electrode has a thickness of 0.1μ, the light shielding film has a thickness of 0.2μ, and the alignment film has a thickness of 0.1μ, making the color filter layer (5) significantly thicker.
In a cell with a cell gap of about 10 μm, there is a large difference in cell gap between the region (display region) where the color filter layer (5) is located and the region (non-display region). As a result, problems such as display unevenness that significantly deteriorate the display quality occur.

However, in the present invention, the color filter layer (5) is arranged not only on the interdigital part of the display area but also on the wiring line of the non-display area, so the above-mentioned problem does not occur, and the color filter layer (5) It is possible to prevent uneven capping due to

Such a color filter layer (5) can be easily formed on the electrode on the substrate (1a) by electrodeposition, for example, forming red (5a) and green (5b) filter layers. .

In addition, an alignment film (not shown) made of polyimide resin or the like is formed on each of the substrates (la) and (Ib), and the segment electrodes (2) and common electrodes (3) are arranged to face each other, and a seal is formed. They are integrated using adhesives such as materials to form cells. Liquid crystal is injected into the cell using a well-known method to produce a predetermined display.

In other words, if voltage is applied to the red segment electrode, the display will be red, if voltage is applied to the green segment electrode, the display will be green, and if voltage is applied to both electrodes, the mixture of red and green will display yellow. Multi-color display is possible.

(G) Effects of the Invention As detailed above, according to the present invention, it is possible to provide a liquid crystal display device that performs multi-color display with significantly improved display quality by forming segment electrodes in an interdigital shape. can.

Furthermore, since the present invention includes a light-shielding film, the film last can be significantly improved compared to conventional products.

Furthermore, in the present invention, the cell gap can be made constant by actively disposing color filter layers in non-display areas other than the display area of the interdigital portion. As a result, display unevenness and the like can be prevented.

[Brief explanation of the drawing]

Figure 1A is a plan view of one board, Figure 1B is a plan view of the other board, Figure 1C is an enlarged view of Figure 1A, and Figure 2 is Figure 1A.
FIG. 3 is a cross-sectional view of FIG. (la) (lb) are transparent substrates, (2) are segment electrodes, <3) are common electrodes, (4) are light shielding films, (5)
is a color fill layer.

Claims (6)

[Claims] (1) In a liquid crystal display device in which a pair of glass substrates are arranged facing each other, a plurality of segment electrodes are formed on the inner surface of one of the glass substrates, a common electrode is formed on the inner surface of the other glass substrate, and a desired segment display is performed. , a plurality of segment electrodes formed on the one glass substrate have an interdigital shape, a predetermined color filter is arranged on the interdigital shape electrode, and a light shielding layer is arranged in a non-display area on the common electrode. A liquid crystal display device characterized by: (2) The liquid crystal display device according to claim 1, wherein the color filter is arranged on the segment electrode and a segment routing line extending from the segment electrode. (3) The liquid crystal display device according to claim 1, wherein the color filter is formed by an electrodeposition method. (4) The liquid crystal display device according to claim 1, wherein the light shielding layer is made of a metal such as nickel or chromium. (5) The liquid crystal display device according to claim 1, wherein the common electrode has a single structure. (6) The liquid crystal display device according to claim 1, wherein the common electrode is divided into at least two parts.