JPH11183888A - Liquid crystal display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid crystal display device capable of displaying a bright picture with high contrast and constituting the whole device as a slim type. SOLUTION: A substrate 2 and a transparent substrate 3 are mutually joined through a frame-like seal material 4, scatter type liquid crystal 5 is sealed in a gap between both the substrates 2, 3 on the inside of the seal material 4 to constitute a display panel 1 and a reflection panel 6 is arranged on the outside of one substrate 2 in the panel 1. In this case, light scattering particles 7 are mixed into the seal material 4, an LED 10 to be a light source is formed on a terminal part 2a constituted of a part projected to the outside of the seal material 4 and light from the LED 10 is made to enter into the seal material 4, scattered in the seal material 4 through the particles 7 and made to enter into the panel 1.

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 for displaying images such as characters and figures by controlling the transmission of light with an electro-optical material.

[0002]

2. Description of the Related Art In a liquid crystal display device of this type, a pair of transparent substrates made of glass or the like are joined via a frame-shaped sealing material, and an electric field is applied to a gap between the two substrates inside the sealing material. A display panel is constructed by enclosing an electro-optical material (liquid crystal) whose optical characteristics change, and the surface side of one of the substrates in the display panel is used as a display section of an image.

In general, in a liquid crystal display device used as a display for a portable information device, a small personal computer, a word processor, or the like, a light source for a backlight is provided on the back side of a display unit in a display panel. A bright image with contrast is displayed.

[0004]

However, if a light source for a backlight is arranged outside the display panel, the thickness of the entire device becomes thicker, and the device can be incorporated into devices such as portable information devices, small-sized personal computers and word processors. Disadvantageous.

The present invention has been made in view of such a point, and its object is to display a bright image with high contrast and to make the whole apparatus thin and thin. It is an object of the present invention to provide a liquid crystal display device capable of performing the above.

[0006]

In order to achieve the above object, a liquid crystal display device according to the present invention comprises a pair of substrates joined to each other via a frame-shaped sealing material, and a substrate gap inside the sealing material. A display panel in which an electro-optical material is sealed,
In a liquid crystal display device having a reflection member provided on one of the substrate surfaces of the display panel, a terminal formed on one of the pair of substrates to protrude outside the sealing material. A light source is provided on the part, and light from the light source is incident on the electro-optical material layer from an outer side surface of the sealing material. According to this liquid crystal display device, light can be supplied from the light source disposed on the terminal portion into the electro-optical material layer between the two substrates. Therefore, a thin display device with a light source can be obtained. Further, the electro-optical material is a scattering type liquid crystal whose light scattering state and light transmission state are controlled by a voltage applied between electrodes provided on the inner surfaces of both substrates. Further, light scattering particles are mixed into the sealing material, the light from the light source is scattered by the light scattering particles, and the scattered light is incident on the electro-optical material layer.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A liquid crystal display device according to the present invention has a display panel in which a pair of substrates are joined via a frame-shaped sealing material, and an electro-optical material is sealed in a gap between the substrates inside the sealing material. And a reflective member provided on one of the substrate surfaces of the display panel, wherein the one of the pair of substrates is formed so as to protrude outside the sealing material on one of the substrates. By providing a small light source on the terminal portion facing the outer side surface of the sealing material interposed between one substrate and the other substrate, the light of the light source is transmitted from the outer side surface of the sealing material to The light is incident on the electro-optical material layer.

Therefore, it is possible to obtain a thin liquid crystal display device that can be illuminated without disposing a backlight on the back of the display panel. Further, it is preferable to use a scattering liquid crystal as the electro-optical material. This allows
The light scattering state and the light transmission state can be controlled by the voltage applied between the electrodes provided on the inner surfaces of both substrates. Further, it is preferable that light scattering particles made of glass particles, glass fibers, or the like that scatter light are mixed into the sealing material. Thereby, the light from the light source can be scattered by the light scattering particles, and the scattered light can be made incident on the electro-optical material. Therefore, a bright image with high contrast is displayed even if no light source for the backlight is provided outside the substrate.

Therefore, in the liquid crystal display device of the present invention, a bright image with contrast can be displayed without providing a light source for a backlight on the back side of the display panel, and therefore, the thickness of the entire device is made thin. For example, when it is used for a display of a portable information device, a small personal computer, a word processor, or the like, it is advantageous to incorporate the device into the device.

[0010]

An embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a sectional view of a liquid crystal display device according to a first embodiment of the present invention, and FIG. 2 is a plan view thereof.

In FIG. 1, reference numeral 1 denotes a display panel. This display panel 1 has one transparent substrate 3 made of a transparent material such as glass.
And the other substrate 2 via a frame-shaped sealing material 4,
A scattering type liquid crystal 5 as an electro-optical material whose optical characteristics change by an electric field is sealed in a gap between the two substrates 1 and 2 inside the sealing material 4.

On the outside of the substrate 2, a reflection plate 6 is provided as a reflection member facing the substrate 2. Then, external light entering the display panel 1 from outside the transparent substrate 3 is reflected by the reflection plate 6 and emitted to the outside of the transparent substrate 3.

On the inner surface of the substrate 2, a number of pixel electrodes (not shown) and thin film transistors (not shown) corresponding to the respective pixel electrodes are formed in a matrix and are arranged in a matrix. On the surface, a single film-shaped counter electrode (not shown) facing all of the pixel electrodes
Are formed.

The sealing member 4 is made of, for example, a transparent resin of a photo-curing type. Light scattering particles 7 made of glass particles, glass fibers, or the like that scatter light are mixed in the sealing member 4. On the outer surface of the transparent substrate 3, a light-shielding tape 8 is attached as a light-shielding member to a portion facing the seal material 4.

One side of the substrate 2 projects relatively largely outside the sealing material 4, and the projecting portion constitutes a terminal portion 2a. An LSI or the like for driving the display panel 1 on the terminal portion 2a. Is provided.

Further, on the terminal portion 2a, a plurality of LEDs 10 as light sources are provided so as to face the sealing material 4 interposed between the transparent substrate 3 and the other substrate 2. A light-shielding tape 11 as a light-shielding member is attached to the outer side surface of the sealing material 4 that does not face the LEDs 10.

In the liquid crystal display device having such a configuration, the display panel 1 is driven through the drive circuit chip 9 and the transmission of light is controlled through the liquid crystal 5. The image is displayed on the display unit 3a on the outer surface of the substrate 3. LED1 when using liquid crystal display
0 is always lit, and light by this illuminating enters the sealing material 4.

Light scattering particles 7 are mixed in the sealing material 4, so that the incident light impinges on the light scattering particles 7 and is scattered in all directions. The light scattered in the seal member 4 spreads into the display panel 1 while reflecting on the inner surfaces of the substrates 2 and 3 and reflecting on the reflector 6. Therefore, the substrate 2
A bright image with contrast is displayed on the display unit 3a even if no backlight light source is provided outside of the display unit.

The outer surface of the substrate 3 facing the sealing material 4 and the sealing material 4 excluding the portion facing the LED 10
Light-shielding tapes 8 and 11 are adhered to the outer sides of the side surfaces of the LED, respectively, so that the light that has entered the sealing material 4 does not leak in unnecessary directions and leaks out. It can be effectively guided into the display panel 1.

As described above, without providing a light source for the backlight outside the display panel 1, a bright image having a high contrast can be displayed by using the LED 10 provided in the terminal portion 2a. For example, when used for a display of a portable information device, a small personal computer, a word processor or the like, it can be advantageously incorporated into the device.

In the first embodiment, the scattering type liquid crystal is used as the electro-optical material. However, as shown in FIG.
TN type or ST as electro-optical material in the gap between
An N-type liquid crystal 5 'is sealed, and one substrate 2 of the display panel 1 is sealed.
The polarizing plates 12 and 1 are provided on the outside of the transparent substrate 3 and on the outside of the transparent substrate 3, respectively.
3 may be provided to display an image. In this case, the light emitted from the LED 10 provided on the terminal portion 2 a is transmitted through the light scattering particles 7 in the sealing material 4 to the display panel 1.
And the light illuminates the inside of the display panel 1 brightly. Further, in each of the above embodiments, the reflection member is provided on the outer surface of the substrate 2, but may be provided on the inner surface facing the electro-optical material layer. In that case, the reflection member and the electrode can also be used, and a thinner display device can be obtained. Further, in each of the above-described embodiments, a transparent substrate is used as the substrate 2, but the substrate 2 may be made of an opaque material, for example, a semiconductor substrate such as Si or GaAs. In that case, the LED arranged in the terminal portion 2a
The device 10 can be easily installed, for example, by forming the device 10 on the substrate 2, and the size can be reduced.

[0022]

As described above, according to the present invention,
Obtaining an image of sufficient brightness by supplying light from the outside of the frame-shaped sealing material from a light source arranged at the terminal portion of the display panel without providing a light source for a backlight behind the display panel Can be. Further, when reflected light is used, even if there is no external light from the front of the display panel, light supplied from the outside of the sealing material can be used, so that a bright image with contrast can be displayed. Further, since there is no need to provide a light source for a backlight behind the display panel, a display device having a small thickness can be formed as a whole.

[Brief description of the drawings]

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

FIG. 2 is a plan view showing the liquid crystal display device according to the first embodiment of the present invention.

FIG. 3 is a sectional view showing a liquid crystal display device according to a second embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Display panel 2 ... Substrate 3 ... Transparent substrate 4 ... Sealing material 5 ... Scattering liquid crystal 6 ... Reflecting plate 7 ... Light scattering particle 8 ... Light shielding tape 9 ... Drive circuit chip 10 ... LED 11 ... Light shielding tape 12 ... Polarizing plate 13 …Polarizer

Claims (3)

[Claims] 1. A display panel in which a pair of substrates are joined via a frame-shaped sealing material, and an electro-optical material is sealed in a gap between the substrates inside the sealing material, and one of the display panels. A reflective member provided on a surface of the liquid crystal display device, wherein a light source is provided on a terminal portion of one of the pair of substrates which is formed to protrude outside the sealing material. A liquid crystal display device, wherein said light is made to enter said electro-optical material layer from an outer side surface of said sealing material. 2. An electro-optic material according to claim 1, wherein said electro-optical material is a scattering type liquid crystal whose light scattering state and light transmission state are controlled by a voltage applied between electrodes provided on the inner surfaces of both substrates. 2. The liquid crystal display device according to 1. 3. The sealing material contains light scattering particles mixed therein, and the light scattering particles scatter light from a light source.
3. The liquid crystal display device according to claim 1, wherein the scattered light is incident on the electro-optical material.