JPH04296825A - Liquid crystal display device - Google Patents

Abstract

PURPOSE:To prevent light leakage from a non-display area as well as an OFF segment of a display area by depositing and arranging a first liquid crystal display panel provided with a shade layer and a second liquid crystal panel through a polarizing plate. CONSTITUTION:A first liquid crystal panel 10 is formed out of a first transparent substrate 11 on which a first display electrode is formed and a second transparent substrate 14 on which a first common electrode 13 is formed, in an integrated manner. A second liquid crystal panel 20 is formed out of a third transparent substrate 12 on which a second display electrode 22 is formed and a fourth transparent substrate 25 on which a second common electrode 24 is formed, in an integrated manner. A polarizing plate 30 is placed between the first and the second liquid crystal panels 10 and 20. A metal shade layer 16 made of metallic material such as nickel is formed on the first as well as the second liquid crystal panels NO, 20. A plurality of fret lines extended from a first segment electrode 12 are arranged on one end of the first transparent substrate 11, and a plurality of first extraction electrodes 15 are formed on the end part of the first transparent substrate 11.

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, and more particularly to improving the light-shielding characteristics of a liquid crystal display device for negative display.

0002

2. Description of the Related Art In general, the display methods of liquid crystal display devices are broadly divided into positive display, which displays black on a white background, and negative display, which displays white on black. Among these, for negative display, a light source such as a lamp is installed on the back of the panel.
By blocking the incident light from the light source in the F segment (non-selected segment) and transmitting it in the ON segment (selected segment), good display was obtained in both bright and dark places. Furthermore, color display can also be performed by providing a color filter on the inside of the two transparent substrates constituting the liquid crystal panel or on the back surface of the liquid crystal panel. However, since light from the back light source leaks slightly from the black part of the background, the contrast between the ON segment and the background is significantly reduced, resulting in a deterioration in display quality. Therefore, a liquid crystal display panel is known in which a light-shielding film made of metal such as nickel or black resin ink is provided in a background portion other than the display area to block leakage light from a light source and improve display quality.

0003

[Problems to be Solved by the Invention] However, although the light-shielding effect of the conventional light-shielding film described above is highly effective in reducing light leakage from the back surface,
Regarding light leakage from segments (non-selected segments), there is no light shielding effect at all, and the contrast between ON and OFF segments becomes low in the display area.
For example, it has not been possible to realize a liquid crystal display panel with excellent display quality for use in audio or OA applications.

0004

[Means for Solving the Problems] The present invention has been made in view of the above-mentioned problems, and includes a first transparent substrate on which a first display electrode is formed, and a first display electrode arranged opposite to the first display electrode. A first liquid crystal display panel in which a first common electrode divided into a plurality of parts and a second transparent substrate on which a light shielding layer provided only in a non-display area is integrally formed; A second transparent substrate in which a second transparent substrate on which electrodes are formed and a second transparent substrate on which a second common electrode is formed, which is arranged opposite to the second display electrode and divided into a plurality of parts, are integrally formed. In a liquid crystal display device that displays a desired shape using a liquid crystal display panel, a first transparent substrate on which the first display electrode is formed and a second transparent substrate on which the second display electrode is formed. The first
Further, each extraction electrode extending from the segment electrode constituting the second display electrode is provided at the ends of the first and second transparent substrates so as to overlap.

[0005]

[Operation] According to the present invention, by arranging the first liquid crystal display panel provided with a light-shielding layer and the second liquid crystal display panel in a stacked manner with a polarizing plate interposed therebetween, light leakage from the non-display area can be prevented from leaking from the first liquid crystal display panel. Light can be blocked by a light shielding layer provided on the liquid crystal display panel, and light leakage from the OFF segment of the display area of the liquid crystal display device can be prevented by the second liquid crystal display panel and the polarizing plate and the interposed between the first and second liquid crystal display panels. Light can be blocked by a polarizing plate provided on the light source side of the second liquid crystal display panel, and further by a polarizing plate provided on the first liquid crystal display panel and the front side of the first liquid crystal display panel. As a result, in one liquid crystal display device, light leakage from the non-display area and the OFF segment area of the display area can be prevented.

Furthermore, according to the present invention, the substrates on the segment side are closely stacked so that the respective extraction electrodes overlap, which is advantageous when driving the same segment electrodes.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The liquid crystal display device of the present invention will be explained below based on the embodiments shown in FIGS. 1 to 4. FIG. 1 is a cross-sectional view showing the liquid crystal display device of the present invention, in which the first display electrode (12
) and a second transparent substrate (14) on which a first common electrode (13) is formed. , a third transparent substrate (2) on which a second display electrode (22) is formed;
1) and a fourth transparent substrate (25) on which a second common electrode (24) is formed. 10
) (20) and a polarizing plate (30) interposed between them.

The first liquid crystal display panel (10) is formed by integrating the first and second transparent substrates (11) and (14) as described above. That is, the first transparent substrate (
11) A plurality of first display electrodes (hereinafter referred to as first segment electrodes) (12) having a desired shape are formed using a transparent conductive material such as indium oxide. The plurality of lead lines extending from the first segment electrode (12) are each arranged at one end of the first transparent substrate (11), and a predetermined line is provided at the end of the first transparent substrate (11). A plurality of first extraction electrodes (15) are formed at a pitch.

On the other hand, on the second transparent substrate (14), a divided first common electrode (hereinafter referred to as , referred to as the first common electrode.)(1
3) is formed. The first common electrode (13)
A metal light-shielding layer (16) made of metal such as nickel is formed on the top to shield the non-display area from light, thereby preventing light leakage from the back surface in the non-display area.

[0010] First and second transparent substrates (11) (14)
On top is an organic alignment film (17) (1) for aligning the liquid crystal.
8) is formed by coating. Thereafter, a predetermined interval is controlled by the sealing material (19), and liquid crystal is injected into the space to form the first liquid crystal display panel (10). Then the second
The liquid crystal display panel (20) will be explained. The second liquid crystal display panel (20) has third and fourth transparent substrates (21
) (25). A second segment electrode (12) similar to the first segment electrode (12) formed on the first transparent substrate (11) is formed on the third transparent substrate (21).
A segment electrode (22) is formed, and a lead-out line extending from the second segment electrode (22) is arranged at the end of the third transparent substrate (21), and a second lead-out electrode (26) is formed. It is formed. This second extraction electrode (26
) is formed so as to correspond to a position facing the first extraction electrode (15) described above. That is, the second extraction electrodes (26) are formed at the same intervals as the first extraction electrodes (15).

By the way, the second liquid crystal display panel (20)
The display pattern displayed on the screen and the first liquid crystal display panel (1
The sizes of the display patterns displayed in 0) are not the same,
The display pattern displayed by the second liquid crystal display panel (20) is formed slightly larger (see FIG. 2). In the present invention, the first and second liquid crystal display panels (10
) (20), this is to prevent the shape of the segment shape from being deformed when the display pattern is viewed obliquely due to the influence of the parallax angle.

The size of the display pattern displayed on the second liquid crystal display pattern is explained using, for example, FIG.

[0013]

[Math 1]

The relationship between a and σ can be determined from the following relationship (in this case, the refractive index of the polarizing plate is not considered). Here, if n = 1.5, d = 1.3 mm (0.55 mm glass substrate x 2 + polarizing plate approximately 0.2 mm), σ = 45
The condition that the segment shape does not change up to

0015
]

[Math 2]

[0016] The first and second liquid crystal display panels (
10) (20) is the extraction electrode (15) as shown in Figure A.
) (26) formed thereon are laminated together by placing them in, for example, double-sided tape or a frame (not shown) with a polarizing plate (30) in between, so that the substrates (11) and (21) on which the substrates (26) are formed are in close contact with each other. With this laminated arrangement, the first and second extraction electrodes (15) and (26) overlap and are arranged on opposing surfaces, so that the same segment of the first and second display panels can be Convenient connection when driving.

FIG. 4 shows the relationship between the rubbing direction and the absorption axis of the polarizing plate in the liquid crystal display device of the present invention, which is set for negative display. That is, when the segment electrodes displaying the same display pattern of the first and second liquid crystal display panels (10) and (20) are driven, the light from the light source is transmitted through only the selected display pattern and displayed. . On the other hand, the non-selected display pattern is blocked by the polarizing plates (32), (30), and the first and second liquid crystal display panels (10) and (20), and the selected display pattern and the non-selected display pattern are blocked. The contrast in the display pattern area with the selected display pattern can be improved.

[0018]

As described in detail above, according to the present invention, the first liquid crystal display panel provided with a light shielding layer and the second liquid crystal display panel are laminated with each other with a polarizing plate interposed therebetween, thereby making it possible to display non-display images. Light leakage from the OFF segment of the display area of the liquid crystal display device can be blocked by a light shielding layer provided on the first liquid crystal display panel, and light leakage from the OFF segment of the display area of the liquid crystal display device can be blocked by the second liquid crystal display panel and the first liquid crystal display panel.
, a polarizing plate interposed between the second liquid crystal display panels, a polarizing plate provided on the light source side of the second liquid crystal display panel, and further a first liquid crystal display panel and a polarizing plate provided on the front side of the first liquid crystal display panel. Light can be blocked by the polarizing plate, and light leakage from the non-display area and the OFF segment area of the display area can be prevented. As a result, a liquid crystal display device with high quality display contrast can be provided, which has a great influence on OA equipment such as audio equipment.

Furthermore, in the liquid crystal display device of the present invention, since the display pattern of the second display panel is formed larger than the display pattern of the first display panel, the shape of the display pattern is deformed depending on the parallax angle. It can be displayed without any Further, in the present invention, since the extraction electrodes of each panel are arranged facing each other and overlapping each other, there is an advantage that connection with an external circuit can be easily performed.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing a liquid crystal display device of the present invention.

FIG. 2 is a plan view for explaining a display pattern of the present invention.

FIG. 3 is a diagram illustrating how to determine the size of a display pattern according to the present invention.

FIG. 4 is a diagram showing the relationship between the rubbing direction of the liquid crystal display device of the present invention and the absorption axis of the polarizing plate.

[Explanation of symbols]

(10) First liquid crystal display panel (20)
Second liquid crystal display panel (30) Polarizing plate (15) First extraction electrode (26) Second extraction electrode

Claims (5)

[Claims] 1. A first transparent substrate on which a first display electrode is formed, and a second common electrode on which a first common electrode is arranged facing the first display electrode and divided into a plurality of parts. A first liquid crystal display panel integrally formed with a transparent substrate, a second transparent substrate formed with a second display electrode, and a second liquid crystal display panel arranged opposite to the second display electrode and divided into a plurality of parts. In a liquid crystal display device that displays a desired shape using a second liquid crystal display panel integrally formed with a second transparent substrate on which a common electrode is formed, the second transparent substrate on which the first display electrode is formed; 1 transparent substrate and a second transparent substrate on which the second display electrode is formed are laminated with a polarizing plate interposed so as to face each other, and the segments constitute the first and second display electrodes. A liquid crystal display device characterized in that respective extraction electrodes extending from the electrodes are provided at the ends of the first and second transparent substrates so as to overlap with each other. 2. The liquid crystal display device according to claim 1, wherein a light shielding layer made of metal is formed on the first and second liquid crystal display panels. 3. The liquid crystal display device according to claim 2, wherein the light shielding layer is formed on a second transparent substrate on which a first common electrode is formed. 4. The liquid crystal display device according to claim 1, further comprising a polarizing plate disposed on the surfaces of the first and second liquid crystal display panels arranged in a stacked manner. 5. The liquid crystal display device according to claim 1, wherein the light source irradiates from the second liquid crystal display panel side through a diffusion plate.