JPH0511239A - Liquid crystal display - Google Patents

Abstract

PURPOSE:To improve the visual recognizing characteristic of display images by decreasing the reflected light to external light. CONSTITUTION:An external light reflection preventive layer 24 is provided between a polarizing plate 4 and protective cover 22 of a liquid crystal panel 2. This external light reflection preventive layer 24 is constituted of an oily material having approximately the same refractive index together of a protective cover layer 22 and the polarizing plate 4 of the liquid crystal panel 2.

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 having a protective cover in front of a liquid crystal panel.

[0002]

2. Description of the Related Art As shown in FIG. 2, a liquid crystal panel 2 based on an active matrix driving system using thin film transistors includes a first polarizing plate 4, a counter substrate 6, a color filter 8 from the incident direction side of external light X. There is one configured by providing the liquid crystal 10, the thin film transistor substrate 12, and the second polarizing plate 14 in this order. 16 is a black matrix,
Reference numeral 18 is a thin film transistor. Since the more detailed structure and operation of the liquid crystal panel 2 having such a structure are well known, the description thereof will be omitted.

In this liquid crystal panel 2, when the thickness of the liquid crystal 10 between the counter substrate 6 and the thin film transistor substrate 12 changes due to the mechanical force from the outside, the thickness change portion occurs. Since the amount of transmitted light of the outside light changes, and as a result, the display image as a liquid crystal display is impaired, in order to prevent this, a protective cover 22 is provided in front of the first polarizing plate 4 with an air layer 20 interposed. The one provided is known.

[0004]

Although light is reflected on the boundary surface of members having different refractive indexes as an optical property, in the case of the above structure, the boundary surface with the air existing on the front surface of the protective cover 22, On the boundary surface with the air layer 20 existing on the rear surface of the protective cover 22 and on the boundary surface with the air layer 20 existing on the front surface of the first polarizing plate 4, air, the protective cover 2
2 and the first polarizing plate 4 have different refractive indices of light, the reflected light X shown in FIG.
1, X2, X3 will occur. Such reflected light X
If 1, X2 and X3 occur, the visibility of the displayed image on the liquid crystal display is significantly impaired, especially in a bright environment.

Therefore, an object of the present invention is to improve the visibility of a display image by reducing the reflected light with respect to the external light.

[0006]

A liquid crystal display of the present invention has a liquid crystal panel, a protective cover, and an external light antireflection layer, and the liquid crystal panel is a polarizing plate into which external light is incident from the front. The protective cover is made of a material having the same or substantially the same optical refractive index as the polarizing plate, and is disposed in front of the polarizing plate, and the external light antireflection layer has a protective cover. Also, it is characterized in that it is made of a liquid having substantially the same optical refractive index as that of the polarizing plate and is disposed between the polarizing plate and the protective cover.

The external light antireflection layer is preferably composed of an oily material.

[0008]

[Function] Since the external light antireflection layer between the polarizing plate of the liquid crystal panel and the protective cover is made of liquid, even if a mechanical force acts on the protective cover, the mechanical force prevents the external light reflection. Since it is absorbed by the layer, there is no influence on the thickness of the liquid crystal on the rear side of the polarizing plate, and the polarizing plate, the protective cover, and the external light antireflection layer are made of materials having substantially the same light refractive index. From
External light that has entered through the protective cover is prevented from being reflected at the boundary surface between the protective cover and the external light antireflection layer and the boundary surface between the external light antireflection layer and the polarizing plate. .

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a sectional view of an embodiment of the present invention,
The parts corresponding to those of the conventional example according to FIG. 2 are denoted by the same reference numerals, and detailed description of the parts having the same reference numerals is omitted.

In this embodiment, the first polarizing plate 4 of the liquid crystal panel 2 and the protective cover 22 are made of a material having the same light refractive index, such as acrylic (light refractive index of about 1.5) or substantially the same light refractive index. Of the refractive index, and instead of the air layer (having a light refractive index of about 1) between the polarizing plate 4 and the protective cover 22, this also has the same light refractive index as the light refractive index. It is characterized in that it is filled with an oil-like material having the above, and this is used as the external light antireflection layer 24.

With this feature, even if a mechanical force is applied to the protective cover 22, the mechanical force is applied to the external light antireflection layer 2.
Since 4 is an oil-like material, it is absorbed here, so that there is no effect on the thickness of the liquid crystal 10 on the rear side of the first polarizing plate 4, and the first polarizing plate 4 and the protective cover 22 are included.
And the external light antireflection layer 24 are made of a material having the same or substantially the same refractive index, and the external light antireflection layer 24 is made of a material having the substantially same refractive index, external light incident through the protective cover 22 is The reflection at the boundary surface between the protective cover 22 and the external light antireflection layer 24 and the boundary surface between the external light antireflection layer 24 and the first polarizing plate 4 is prevented or reduced.

[0012]

As is apparent from the above description,
According to the present invention, since the external light antireflection layer is provided between the polarizing plate of the liquid crystal panel and the protective cover, and the external light antireflection layer is liquid, mechanical force acts on the protective cover. However, the mechanical force is absorbed by the external light antireflection layer, and the influence on the thickness of the liquid crystal on the rear side of the polarizing plate is eliminated.

Since the polarizing plate and the protective cover are made of the same or substantially the same material having the same refractive index, and the external light antireflection layer is made of the material having the substantially same refractive index as these, the protective cover is interposed. The incident external light is prevented or reduced from being reflected on the boundary surface between the protective cover and the external light antireflection layer and the boundary surface between the external light antireflection layer and the polarizing plate. The visibility as a display, especially in an environment with bright surroundings, can be greatly improved.

[Brief description of drawings]

FIG. 1 is a sectional view of an embodiment of the present invention.

FIG. 2 is a sectional view of a conventional example.

[Explanation of symbols]

2 LCD panel 4 First polarizing plate 6 Counter substrate 8 color filters 10 liquid crystal 12 Thin film transistor substrate 14 Second polarizing plate 22 Protective cover 24 External light antireflection layer

Claims (2)

[Claims] 1. A liquid crystal panel (2) and a protective cover (2)
2) and an external light antireflection layer (24), the liquid crystal panel (2) includes a polarizing plate (4) to which external light is incident from the front, and the protective cover (22) is , Which is made of a material having the same or substantially the same optical refractive index as that of the polarizing plate (4) and is arranged in front of the polarizing plate (4), and the external light antireflection layer (24) is a protective layer. A liquid material composed of a material having an optical refractive index substantially the same as that of the cover (22) and the polarizing plate (4), the polarizing plate (4) and the protective cover (22).
A liquid crystal display characterized by being arranged between and. 2. The liquid crystal display according to claim 1, wherein the external light antireflection layer is made of an oil-like material.