JPH05196929A - Method for removing reflection of display surface - Google Patents

Abstract

PURPOSE:To decrease specular reflection and to improve the visibility of the display surface of a display device by forming the display surface as a recessed surface and adhering a polarizer to the rear surface side of a transparent plate disposed on the front surface of a liquid crystal display element. CONSTITUTION:The liquid crystal display element is constituted by adhering the polarizer 1 to the outer surface, which is the recessed surface having >=40cm and <=200cm radius of curvature of a 1st glass substrate 2 having <=1.5 refractive index, adhering the polarizer 6 to the outer surface of the 2nd glass substrate 5, holding a liquid crystal member 4 consisting of a 1st transparent electrode, a 1st orientation control film, a liquid crystal, a 2nd orientation control film and a 2nd transparent electrode by the 1st glass substrate 2 and the 2nd glass substrate 5 and sealing the substrates by a sealing material 3. Incident external light 8 on the surface of this liquid crystal display element 7 is reflected and guided to the outside of a visual field as the surface is the concave surface. The specular reflection on the display surface is thus eliminated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for removing display surface reflection.

[0002]

2. Description of the Related Art Conventionally, for example, in a CRT display device, its display surface is unavoidably convex due to its operating principle. The display surface shape of the liquid crystal display device is almost flat. Cross-sectional views of a conventional liquid crystal display device are shown in FIGS. The liquid crystal display device comprises a liquid crystal display element 7 including polarizers 1 and 6, glass substrates 2 and 5, a sealing material 3 and a liquid crystal member 4, and a protective plate 9. Conventionally, the surface of the protective plate 9 is almost flat, and rarely, there is only a convex surface for design reasons.

[0003]

By the way, in the various display devices of the related art, since the display surface thereof is a plane, the incident external light is reflected directly in the direction of the line of sight, and the display surface is illuminated to reduce the visibility. In addition, since it is a convex surface, the incident external light is reflected in the direction of the line of sight to a level greater than that of a flat surface, and the visibility is further reduced.

In order to solve such a problem, a method of arranging a protective plate having an antiglare treatment on the display surface of each of the above-mentioned various display devices is generally used. In this method, external light is scattered to some extent. However, there is a problem in that it is not possible to completely prevent external light from being reflected in the line-of-sight direction and shining on the display surface to reduce visibility. Therefore, in order to solve such a conventional problem, the present invention improves the visibility by guiding the external light reflected on the display surface to the outside of the field of view and reducing the light reflected without passing through the polarizing plate. The purpose is to improve.

[0005]

The method for removing reflection on the display surface of the present invention is characterized in that the display surface of the display device has a concave surface shape.

Further, a transparent plate having a flat rear surface and a concave front surface is disposed on the front surface of the display surface of the display device via a transparent medium. The radius of curvature of the concave surface is 40 cm or more and 200 cm or less. If the radius of curvature is less than 40 cm, the display is distorted due to the lens effect, and if it exceeds 200 cm, the effect of removing the reflection on the display surface is lost.

Further, the material constituting the display surface having the concave surface has a refractive index of 1.5 or less.
If the refractive index exceeds 1.5, the display is distorted due to the lens effect.

Further, a polarizer is adhered to the back side of a transparent plate arranged on the front side of the liquid crystal display device.

[0009]

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

(Embodiment 1) FIG. 1 is a view showing a first embodiment of the present invention and is a sectional view of a liquid crystal display device comprising a liquid crystal display element 7. The liquid crystal display element 7 has a refractive index of 1.470.
The polarizer 1 is adhered to the outer surface of the first glass substrate 2 which is a concave surface having a radius of curvature of 70 cm, and the second glass substrate 5
A polarizer 6 is adhered to the outer surface of the first glass substrate 2 and the second glass substrate 5, and a first transparent electrode, a first alignment control film, a liquid crystal, a second alignment control film, and a second alignment control film. A liquid crystal member 4 composed of two transparent electrodes is sandwiched and sealed with a sealing material 3. The external light 8 incident on the surface of the liquid crystal display element 7 is
Since it is a concave surface, it is reflected and guided to the outside of the field of view, and specular reflection on the display surface is eliminated. As a result, the visibility of the liquid crystal display surface is considerably improved.

(Embodiment 2) FIG. 2 is a view showing a second embodiment of the present invention and is a sectional view of a liquid crystal display device comprising a liquid crystal display element 7, a transparent medium 10 and a protective plate 9. The liquid crystal display element 7 includes a polarizer 1, a first glass substrate 2, a sealing material 3,
It is composed of a liquid crystal member 4, a second glass substrate 5 and a polarizer 6. The transparent medium 10 is composed of a cellulose acetate derivative having adhesiveness and a refractive index equal to that of the glass substrate 2. The protective plate 9 is a transparent plate having a flat surface on the back side and a concave surface having a curvature radius of 70 cm on the front side, and is made of an acrylic plate having a refractive index of 1.490. The outer surface of the liquid crystal display element 7 and the protective plate 9
The back surface of is adhered by the transparent medium 10.

External light 8 incident on the surface of the protective plate 9
Since it is a concave surface, it is reflected and guided to the outside of the visual field, and specular reflection on the surface of the protective plate is eliminated, and as a result, the visibility of the liquid crystal display surface is considerably improved.

(Embodiment 3) FIG. 3 is a view showing a third embodiment of the present invention and is a perspective view of a liquid crystal display device comprising a liquid crystal display element 7, a transparent medium 10 and a protective plate 9. The liquid crystal display element 7 includes a polarizer 1, a first glass substrate 2, a sealing material 3,
It is composed of a liquid crystal member, a second glass substrate 5 and a polarizer 6. This is the liquid crystal display element 7 of Example 2 shown in FIG.
The configuration is the same as the above. The transparent medium 10 is composed of a cellulose acetate derivative having adhesiveness and a refractive index equal to that of the glass substrate 2. The protective plate 9 is a transparent plate having a flat surface on the back side and a spherical surface with a curvature radius of 70 cm on the front side, and has a refractive index of 1.
It is composed of 490 acrylic plates. The outer surface of the liquid crystal display element 7 and the back surface of the protective plate 9 are adhered by a transparent medium 10.

External light 8a incident on the surface of the protective plate 9 from the left side of FIG. 3 is reflected and guided to the outside of the visual field because it is a spherical surface. On the other hand, external light 8b incident from the back side of FIG.
Similarly, the light is reflected and guided outside the field of view. As described above, as compared with the second embodiment of the present invention, light from a wider range of directions is reflected and guided to the outside of the field of view, mirror reflection on the surface of the protective plate is eliminated, and the visibility of the liquid crystal display surface is improved. Improve dramatically.

(Embodiment 4) FIG. 4 is a view showing a fourth embodiment of the present invention and is a sectional view of a liquid crystal display device comprising a liquid crystal display element 7 and a protective plate 9. The liquid crystal display element 7 includes a polarizer 1, a first glass substrate 2, a sealing material 3, a liquid crystal member 4, a second glass substrate 5, and a polarizer 6. Protective plate 9
Is a transparent acrylic plate whose surface side is anti-glare treated. Although the polarizer 1 was conventionally adhered to the first glass substrate 2, it was adhered to the protective plate 9 in this embodiment.

External light 8 incident on the surface of the protective plate 9
Is an anti-glare treated surface, so that it scatters and specular reflection on the surface of the protective plate is suppressed. On the other hand, the external light 8 transmitted through the protective plate 9 is weakened by being transmitted through the polarizer 1 adhered to the back surface of the protective plate 9, and then the first glass substrate 2
On the outer surface of the. Since the main component of this reflected light is s-polarized light, if the polarizer 1 is arranged in a direction that absorbs it, a greater effect can be obtained. In this way, the reflected light that has not passed through the polarizer is reduced as compared with the conventional liquid crystal display element in which the polarizer 1 is bonded to the outer surface of the first glass substrate 2. As a result, the visibility of the liquid crystal display surface is dramatically improved.

(Comparative Example 1) In Example 3, a polystyrene plate having a refractive index of 1.600 was used as a protective plate instead of the acrylic plate having a refractive index of 1.490. In this case, the display is significantly distorted due to the lens effect of the protective plate. It is not desirable to use a substance having such a large refractive index as a material for forming the concave surface because the disadvantage due to the distortion of the display becomes larger than the advantage due to the removal of the reflection on the display surface.

(Comparative Example 2) In Example 3, the radius of curvature was 7
35cm radius of curvature instead of 0cm concave transparent plate
A transparent plate having a concave surface was used as a protective plate. in this case,
The display is distorted due to the lens effect of the protective plate. It is not desirable to use a transparent plate having a concave surface with a radius of curvature of less than 40 cm as a protective plate as described above because the disadvantage due to the display distortion is larger than the advantage due to the removal of the display surface reflection.

COMPARATIVE EXAMPLE 3 In Example 3, a radius of curvature of 250 was used instead of the transparent plate which was a concave surface having a radius of curvature of 70 cm.
A transparent plate having a concave surface of cm was used as a protective plate. In this case, the visibility is not improved due to the specular reflection on the display surface. It is not desirable to use a transparent plate having a concave surface with a radius of curvature of more than 200 cm as a protective plate because the effect of removing display surface reflection is lost.

Although the embodiments of the present invention have been described above using the liquid crystal display device, the present invention is not limited to this, and can be similarly applied to any display device.

[0021]

The method for removing display surface reflection of the present invention has the effect of eliminating the specular reflection on the display surface and improving the visibility of the display surface by making the display surface of the display device concave.

Further, by adhering the polarizer to the back side of the transparent plate disposed on the front surface of the liquid crystal display element, specular reflection on the surface of the liquid crystal display element is reduced, and the visibility of the display surface is improved.

[Brief description of drawings]

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

FIG. 2 is a sectional view of a liquid crystal display device according to a second embodiment of the present invention.

FIG. 3 is a perspective view of a liquid crystal display device according to a third embodiment of the present invention.

FIG. 4 is a sectional view of a liquid crystal display device according to a fourth embodiment of the present invention.

FIG. 5 is a sectional view of a conventional liquid crystal display device.

FIG. 6 is a cross-sectional view of a conventional liquid crystal display device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Polarizer 2 ... Glass substrate 3 ... Sealing material 4 ... Liquid crystal member 5 ... Glass substrate 6 ... Polarizer 7 ... Liquid crystal display element 8, 8a, 8b ... External light 9 ... Protective plate 10 ... Transparent medium

Claims (5)

[Claims] 1. A method of removing display surface reflection, wherein the display surface shape of the display device is a concave surface. 2. A method of removing display surface reflection, wherein a transparent plate having a flat rear surface and a concave front surface is disposed on the front surface of the display surface of the display device via a transparent medium. 3. The radius of curvature of the concave surface is 40 cm or more and 200 or more.
The method for removing display surface reflection according to claim 1 or 2, wherein the method is less than or equal to cm. 4. The refractive index of the substance forming the display surface having the concave surface is 1.5 or less.
Alternatively, the method of removing display surface reflection according to claim 2. 5. A method for removing reflection on a display surface, which comprises bonding a polarizer to the back side of a transparent plate arranged on the front surface of a liquid crystal display element.