JPH09311353A - Liquid crystal display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid crystal display device for displaying a gold-colored background which has a bright display plane and the high contrast ratio. SOLUTION: In this liquid crystal display device, guest/host type-first liquid crystal panels 2, to which a yellow or orange-colored dichroic coloring matter is added, are laminated in the front of a reflecting plate 1 whose surface constitutes a mirror-finished surface, and light scattering mode type-second liquid crystal panels 3 are laminated in the front thereof. Picture elements of the respective panels are faced each other, and when the electric field to both liquid crystal panels is kept unimpressed, liquid crystal molecules of the first liquid crystal panels 2 become horizontal to the substrate and turn yellow, while liquid crystal molecules of the second liquid crystal panels 3 become perpendicular to the substrate and turn transparent, and the background is displayed so as to look gold-colored with a reflected light from the reflecting plate 1. In the picture elements in which the electric field is impressed, the liquid crystal molecules of the first liquid crystal panels become perpendicular to the substrate and turn transparent, while the liquid crystal molecules of the second liquid crystal panels are displayed slightly opaque and whity by scattering of the light. The bright and white-colored display with the gold-colored background or display in reverse thereof is achieved, and the display plane seemingly high-ranking is obtained.

Description

Detailed Description of the Invention

[0001]

[0001] The present invention relates to a liquid crystal display device.

[0002]

2. Description of the Related Art Conventionally, a background of a display surface of a liquid crystal display device is colored with a specific color to enhance the contrast of a display screen. The first such liquid crystal display device
As an example, there is a liquid crystal display device in which a TN (twisted nematic) type liquid crystal panel is laminated on the front surface of a reflecting plate having a gold mirror surface so that the background color is gold and black is displayed.

[0003]

In the above-mentioned conventional example, it is usually necessary to provide a polarizing plate on the front surface of the TN type liquid crystal panel, and a large amount of light is lost by the polarizing plate, so that the display surface becomes dark. There is. In addition, since a black display is provided on a dark gold background as described above, there is a problem of lacking a sense of luxury.

[0004]

In order to solve the above problems, the liquid crystal display device of the present invention has a yellow or orange guest-host type first liquid crystal panel on the front surface of a reflector having a mirror surface. A light-scattering mode type second liquid crystal panel is further laminated on the front surface thereof. Then, the second liquid crystal panel in a portion of the first liquid crystal panel facing the pixel displaying yellow or orange is made to be in a light transmitting state so that the mirror surface of the reflection plate and the yellow or orange color overlap with each other so that the first liquid crystal panel looks like gold. Displayed on. On the other hand, when the pixel of the second liquid crystal panel facing the pixel of the first liquid crystal panel which is in the light transmitting state is set to the light scattering state (white turbid state), it is bright due to the mirror surface and the white turbidity of the reflecting plate. By controlling to display white, bright and elegant display in gold and white is possible.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION According to the present invention, a guest-host type first liquid crystal panel in which a yellow or orange dichroic dye is added to nematic liquid crystal is laminated in front of a reflector having a mirror surface, and A second liquid crystal panel of a light scattering mode type is laminated in front of the first liquid crystal panel. Second
The liquid crystal panel of No. 2 is in a light transmitting state in the portion facing the pixels of the first liquid crystal panel that is colored yellow or orange, and is in the cloudy state in the portion facing the pixels of the first liquid crystal panel in the light transmitting state. It is controlled so that

[0006]

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

FIG. 1 is an enlarged view showing a cross-sectional state of a specific pixel portion of a liquid crystal display device according to the present invention. As shown in the figure, a first liquid crystal panel 2 is laminated on the front surface of the reflection plate 1, and a second liquid crystal panel 3 is further laminated on the front surface thereof.

The reflector 1 is a silver glossy paper.

The first liquid crystal panel 2 includes transparent electrodes 22 and 2 made of ITO or the like on the inner surface of transparent substrates 21 and 21 made of glass or the like.
2 is formed. Alignment films 23 and 23 are formed on the transparent electrodes 22 and 22 by spin coating of a vertical alignment material. In the liquid crystal cell surrounded by the encapsulants 24, 24 such as an epoxy resin, a nematic liquid crystal having a positive dielectric constant anisotropy, a yellow dichroic dye, and liquid crystal molecules about three rotations between the substrates. A guest-host liquid crystal 25 mixed with a chiral agent is wound so as to be wound in a spiral. In this liquid crystal panel, when no electric field is applied between the transparent electrodes 22 and 22 (see FIG. 2A), the long axis direction of the liquid crystal molecules is parallel to the rubbing direction, and the spiral axis is perpendicular to the substrate. The orientation state becomes

Like the first liquid crystal panel 2, the second liquid crystal panel 3 has ITO on the transparent substrates 31, 31 made of glass or the like.
Etc. transparent electrode layers 32, 32 are formed. Alignment films 33 and 33 are formed on the transparent electrode layers 32 and 32.
A light-scattering liquid crystal 35 is enclosed in a liquid crystal cell surrounded by sealing agents 34, 34 such as epoxy resin. The light-scattering liquid crystal 35 is a nematic liquid crystal having a negative dielectric anisotropy mixed with a small amount of an ionic additive, and the liquid crystal molecules are vertical when no electric field is applied to the transparent electrodes 32. However, when an electric field is applied, the liquid crystal molecules are disturbed and become cloudy.

First liquid crystal panel 2 and second liquid crystal panel 3
And are stacked so that each pixel matches,
The pixel patterns match when viewed from the front.

Next, the operation will be described.

FIG. 2A shows a first liquid crystal panel 2 and a second liquid crystal panel 2.
The liquid crystal panels are laminated so that the pixels of the liquid crystal panel 3 are aligned with each other, and the application of the electric field to the pixels is turned off.

The liquid crystal molecules of the first liquid crystal panel 2 are the substrate 2
Oriented so as to be parallel to 1, 21 and colored yellow by the dye of the guest-host liquid crystal. At this time, the liquid crystal molecules of the second liquid crystal panel 3 are perpendicular to the substrates 31 and 31, and are in a transparent state in which light incident from the front surface can be transmitted. Therefore, the light that has entered this pixel is reflected by the yellow pigment and the silver mirror surface and displayed as if it appears gold.

On the other hand, FIG. 2B shows a portion in which the application of the electric field to the respective pixels of the liquid crystal panels 2 and 3 facing each other is turned on. In this state, the liquid crystal molecules of the first liquid crystal panel 2 are perpendicular to the substrates 21 and 21, and light is transmitted therethrough to be in a transparent state. On the other hand, the liquid crystal molecules of the second liquid crystal panel 3 are in a cloudy state due to light scattering. Therefore, as shown by the arrow, the light incident from the front side is scattered forward by the liquid crystal molecules in the second liquid crystal panel 3 and is reflected by the silver mirror surface of the reflector 1 to be opaque to the back side of the second liquid crystal panel. Displayed in bright white due to backscattering by reflected light from.

As described above, by controlling the application of the electric field to each pixel of the first liquid crystal panel 2 and the second liquid crystal panel 3 which face each other so as to have the same sign, gold and white can be arbitrarily set. Can be displayed. Therefore, a white display with a gold background or the opposite display is possible, and a liquid crystal display device full of high quality is obtained.

As another embodiment, the liquid crystal 25 of the first liquid crystal panel 2 is a nematic liquid crystal having a negative dielectric constant anisotropy, a yellow dichroic dye, and a half rotation (180) between the substrates.
The liquid crystal 35 in the second liquid crystal display panel 3 is a polymer-dispersed liquid crystal in which a chiral material is added to the transparent electrodes 22 and 32, respectively. When it is not applied, it becomes cloudy due to the light scattering of the polymer dispersed liquid crystal, when the electric field is applied, the pixels of the second liquid crystal panel 3 become transparent, and the yellow color of the first liquid crystal panel 2 is reflected by the reflector 1. It is also possible to reflect and display in gold.

[0018]

According to the present invention, since a deflector is not required, the screen becomes brighter and a liquid crystal display device with a high-class feeling can be obtained by displaying in gold and white. Further, since the display is in gold and white, the contrast ratio is high, and the display is easy to see.

[Brief description of drawings]

FIG. 1 is an enlarged view showing a configuration of the present invention.

FIG. 2 is a cross-sectional view for explaining the operation of the present invention.

[Explanation of symbols]

 1 Reflector 2 First Liquid Crystal Panel 3 Second Liquid Crystal Panel

Claims (1)

[Claims] 1. A guest-host type first liquid crystal panel in which a yellow or orange dichroic dye is added to a nematic liquid crystal is laminated in front of a reflecting plate whose surface is a mirror surface,
A second liquid crystal panel, which is a light scattering mode type, is laminated in front of the first liquid crystal panel, and the second liquid crystal panel is a pixel for displaying in yellow or orange color of the first liquid crystal panel. A liquid crystal display device is controlled such that a light-transmissive state is provided in a facing portion and a white turbid state is provided in a portion facing a light-transmitting pixel of the first liquid crystal panel.