JPS62102224A - Transmission type liquid crystal display device - Google Patents

Abstract

PURPOSE:To expand the stable state of colors of G-H type liquid crystal to expand the life of the liquid crystal by arranging a color filter also on the light source side upper surface of a glass plate of a liquid crystal display element. CONSTITUTION:The liquid crystal display element 7 is constituted by arranging sealing resin 3 on the periphery of two glass plates 2a, 2b, forming transparent electrodes 4a, 4b and compound films 5a, 5b in its inside and sealing G-H type liquid crystal in its inside. The color filter 12 is also applied to the light source side upper surface of the glass plate 2a. Thereby, almost a half of energy for the wavelength in a visual area which is radiated from the light source 1 is absorbed. Consequently, the stable state of colors in the G-H type liquid crystal unstable for opto-chemical reactions can be expanded and the life of the liquid crystal display element can be expanded.

Description

[Detailed description of the invention] Industrial applications The present invention relates to a transmission type liquid crystal display device.

Conventional technology Since liquid crystal displays can display images using low power, they have been widely used in watches, calculators, etc. Recently, large-sized liquid crystal displays in which a large number of liquid crystal display elements are arranged have been developed. This is to meet the public and social needs of providing information to a large number of people at once.

When a large number of transmissive liquid crystal display devices constituting such a large-sized liquid crystal display are arranged, the seal frames included in each device end up forming a grid-like non-display area. Therefore, as proposed by the present inventors in Japanese Patent Application No. 59-61479, the display section can be expanded using a light guide for the purpose of expanding the area of multiple picture elements included in the display element in the display device, that is, the display area. By providing it so as to cover it, it is now possible to form a continuous large screen even when a plurality of display devices are disposed.

Hereinafter, the transmission type liquid crystal display device previously proposed by the present inventors will be described with reference to the drawings.

FIG. 4 is a block diagram of a transmissive liquid crystal display device used in large-sized liquid crystal displays. In this transmission type liquid crystal display device, first, a sealing resin 3 is arranged around two glass plates (transparent substrates) 2a and 2b through which light from a light source 1 passes, forming a certain gap. The above two glass plates 2&
, 2b are formed with transparent electrodes 4a, 4b as thin films, and alignment films 6a, 5b are provided thereon. A G-H type liquid crystal 6 is interposed between the glass plates 2a and 2b, and the liquid crystal display element 7 has the same structure except for the light source 1. When a plurality of liquid crystal display elements 7 are arranged on the same plane as shown in FIG. 9 is pasted on the front surface of the glass plate 2a. This light guide 9
is made of a cylindrical solid body with a reflective film with high reflectance on its inner surface, and is composed of one or more light guide elements provided for one liquid crystal display element 7, and has a directivity for guiding light rays. There is.

In addition, a color filter 1o is provided on the front surface of the light guide 9, which uses a diffuser plate 11 as a base material. , has the function of color reproduction.

Problems to be Solved by the Invention However, in such a configuration, the luminous flux emitted from the light source 1 constituted by a fluorescent lamp directly hits the liquid crystal display element 7. One way to increase the brightness of the display is to increase the amount of light from the light source 1. In this case, the liquid crystal display element 7 is required to have good light resistance. In particular, when the liquid crystal e is of the GH type, there is a drawback in terms of the photochemical stability of the guest dichroic dye, which has the problem of affecting the life of the liquid crystal display element 7.

The present invention solves these conventional problems, and provides a transmission type liquid crystal display that makes it possible to improve the light resistance conditions of the pigment in a liquid crystal display element using a G-H type liquid crystal. The aim is to provide equipment.

Means for Solving the Problems In order to achieve this object, the transmissive liquid crystal display device of the present invention uses the same liquid crystal display element in which a G-H type liquid crystal is arranged between transparent substrates that transmit light from a light source. A large number of liquid crystal display elements are arranged on a flat surface, a color filter is installed on the side of each of the liquid crystal display elements in the direction of the light source, and a reflective film with high reflectance is provided on the inner surface. A plurality of light guides are provided, each of which is composed of one or more light guide elements provided at the same time, and which guides light rays. is provided, and the light guide covers the display portion of the liquid crystal display element, and also covers the joints between the liquid crystal display elements.

Function: According to this configuration, a color filter required for color reproducibility is interposed between the liquid crystal display element and the light source, thereby absorbing approximately half of the energy emitted from the light source for wavelengths in the visible region. As a result, for the pigment in the G1-H type liquid crystal, which is unstable to photochemical reactions, absorption of the amount of light by the color filter extends the life of the liquid crystal display element.

Embodiment FIG. 1 is a sectional view of a transmission type liquid crystal display device according to an embodiment of the present invention. In FIG. 1, reference numeral 7 designates the above-mentioned liquid crystal display element, which includes two glass plates 2a and 2h having the same structure as the liquid crystal display element described in the conventional example.

It consists of a sealing resin 3, a liquid crystal 6, electrodes +a and 4b, an electrode extraction portion 4c, and alignment films 5a and 5b. Further, the configuration of the light guide e is also the same as that of the conventional example. In the present invention, a color filter 12 is also provided on the surface of the glass plate 2a constituting the liquid crystal display element 7 on the light source 1 side. in this case,
There are two configurations of the color filter 12. First, the first
A method of printing color ink on a transparent or semi-transparent substrate 13 of approximately the same size as the liquid crystal display element as shown in FIGS. As shown in FIG. 3, there is a method of printing color ink on the surface of the glass plate 2a facing the light source 1.

Moreover, the color reproducibility consisting of the transmittance of each color filter 10.12 must be made equal to that of a conventional single filter, otherwise the image quality of the display screen will deteriorate. From the configuration of the present invention, the transmittance of the color filter 12 on the light source 1 side is set to 12, and the transmittance of the color filter 1o in front of the display section is set to T.

On the other hand, let T denote a color filter 1o having a conventional configuration. If it is desired to make the brightness of the display screen according to the configuration of the present invention equal to the brightness of the conventional display screen, the following relationship will hold if other conditions are held constant.

“10xT12 = ” ・−・・・・ (
1) For example, if you use a G-H type liquid crystal e and want to extend the life of the liquid crystal display element 7, reduce the transmittance of the color filter 12 on the light source 1 side as much as possible (1). ) If the transmittance T1° of the color filter 10 is determined from the relationship of the equation (2), the amount of light emitted from the light source 1 will be sufficiently absorbed by the color filter 12, and the amount of light applied to the liquid crystal 6 will be reduced.

The configuration of the large liquid crystal display in the present invention is as follows:
Since it is the same as the conventional FIG. 2 except for the color filter 12, the explanation will be omitted.

Effects of the Invention As described above, according to the present invention, the stable state of the dye in the GH type liquid crystal is prolonged for a longer period of time than in the conventional structure, and the life of the liquid crystal display element can be extended.

[Brief explanation of drawings]

Figure 1 is a cross-sectional view of a transmissive liquid crystal display device previously proposed by the inventors, Figure 2 is a schematic configuration diagram of a large liquid crystal display constructed using the liquid crystal display device of Figure 1, and Figure 3. 1 is a sectional view showing an embodiment of a transmission type liquid crystal display device according to the present invention, and FIGS. 4 and 6 are respectively schematic configuration diagrams of essential parts of the device according to the present invention. DESCRIPTION OF SYMBOLS 1...Light source, 2a, 2b...Transparent substrate (glass plate), 3...Nur resin, 4a, 4
b...electrode, 4C...electrode extraction part, sa
, sb... Alignment film, 6... G-H type liquid crystal, 7... Liquid crystal display element, 8...
Seal frame, 9...Light guide, 10.12.
...Color filter, 11...Diffusion plate,
13...Transparent substrate. Name of agent: Patent attorney Toshio Nakao and 1 other person7-
--9C drift 2 (1:2b-11 force glass 1 to 6---Cr-H type liquid crystal Figure 2 Figure 3 Figure 4/θ

Claims (1)

[Claims] A large number of liquid crystal display elements each having a G-H type liquid crystal arranged between transparent substrates that transmit light from a light source are arranged on the same plane, and a color filter is installed on the side surface of each of the liquid crystal display elements in the direction of the light source, It is made of a cylindrical solid body with a highly reflective film on its inner surface, and one layer per liquid crystal display element.
A plurality of light guides are provided, each of which is composed of one or more light guide elements and which guides light rays, and these light guides are installed in front of the liquid crystal display element, and a color filter is also provided in front of the light guide. ,
A transmissive liquid crystal display device, characterized in that the display portion of the liquid crystal display element is covered with the light guide, and the joint between the liquid crystal display elements is also covered.