JPH10293542A - Image display device - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To provide a thin and high-definition large-screen image display device with no uneven illuminance. SOLUTION: A first micro prism array 12 as a first optical element is arranged on a side opposite to a light source 10 of a liquid crystal display device 11 so as to correspond to each liquid crystal display device 11, and a first micro prism array 12 is provided. An image display device is configured by providing a second micro prism array 13 as a second optical element at a predetermined distance from the prism array 12. The first micro prism array 12 emits light emitted from each liquid crystal display device 11 in a direction perpendicular to the display surface to each liquid crystal display device 1.
The first micro prism arrays 12 are refracted in different directions so that they intersect at an equal distance from 1 or the ends of light emitted from the adjacent liquid crystal display devices 11 coincide. The second micro prism array 13 refracts the light emitted from each of the first micro prism arrays 12 in different directions so as to be all light in the direction perpendicular to the display surface.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image display device for displaying a screen by combining a plurality of display devices, and more particularly to a large screen display device installed in a conference room or a hall, a large computer monitor, and the like. Things.

[0002]

2. Description of the Related Art FIG. 7 is a plan view showing a liquid crystal display device, and FIG.
FIG. 3 is a plan view showing a large-screen display device configured by combining a plurality of liquid crystal display devices. FIG. 8 shows the liquid crystal display device 4.
FIG.

As shown in FIG. 7, a liquid crystal display device 11 comprises:
A PWB 16 is arranged around the liquid crystal display panel 15, and two or three sides of the liquid crystal display panel 15 are connected to the PWB 16 via TCPs 17 respectively, and a predetermined number of driver LSIs 18 are arranged.

When such a liquid crystal display device 11 is combined into a large-screen display device as shown in FIG.
The non-image display unit 20 composed of the PWB 16, the TCP 17, and the driver LSI 18 is preferably as small as possible. However, since the non-image display unit 20 cannot be completely eliminated, only the image display unit 19 of the liquid crystal display panel 15 is enlarged. 2. Description of the Related Art Enlarged projection is performed on a screen using a lens or the like.

[0005] In this way, the non-image display section 20 is not projected, and only the image display section 19 is enlarged and projected, so that a seamless large-screen display can be performed on the screen. . A method for performing such a seamless large-screen display will be described below.

FIG. 9 is an explanatory view showing a conventional projection method for displaying a large screen. As shown in FIG. 9, the projection type liquid crystal display device 24 includes a lamp 21 and a condenser lens 2.
2. An image display unit 1 of the liquid crystal display device 11, which comprises a liquid crystal display device 11, a projection lens 23, and a screen 25.
9 is enlarged, and a seamless large-screen display is performed on the screen 25. FIG. 9 shows a case where two liquid crystal display devices 11 are combined.

More specifically, the light emitted from the lamp 21 is passed through the condenser lens 22 to the liquid crystal display device 1.
The light and the light traveling in the direction 1 are collected. Light emitted from the liquid crystal display device 11 is projected onto the screen 2 by the projection lens 23.
5 is projected. At this time, the adjacent liquid crystal display devices 11
By setting the end of the projection image of the image display unit 19 emitted from the screen 25 to coincide on the screen 25, a seamless large-screen display can be performed.

FIG. 10 shows another method. FIG. 10 is an explanatory diagram showing a method using a light guide band for displaying a large screen. As shown in FIG. 10, another method for eliminating the reflection of the non-image display unit 20 on the end face of the light guide band bundle 26 and performing a seamless large-screen display is provided. After the light is transmitted through the light guide 11, the light path is changed by the light guide band 26 corresponding to each pixel of the image display unit 19, and image matching is performed on the end face of the light guide band 26.

According to the method disclosed in Japanese Patent Application Laid-Open No. 5-188340, as shown in FIG. 11, the projection type liquid crystal display device 24 includes the light source 10, the liquid crystal display device 11,
The liquid crystal display device 11 includes a condensing lens 27, an imaging lens 28, a magnifying lens 29, and a screen 25. A predetermined number of pixels of the liquid crystal display device 11 are used as image blocks. Large screen display without any.

More specifically, light emitted from the light source 10 passes through image blocks of the liquid crystal display device 11, passes through the condenser lens 27 for each image block, and is formed by the image forming lens 28 and the magnifying lens 29. The image is enlarged and projected on the screen 25. At this time, by setting the end of the projected image of the image block emitted from the liquid crystal display device 11 to be coincident on the screen 25, a seamless large-screen display can be performed.

[0011]

However, since the projection type as shown in FIGS. 9 and 11 requires a certain projection distance, the depth of the projection type liquid crystal display device cannot be reduced. There is a problem.

When an image is projected, the central portion of the image is generally bright and the peripheral portion of the image tends to be dark. Dark parts alternate with
There is a problem that image quality is significantly reduced.

In particular, the method shown in FIG. 11 is a method using a plurality of lenses as the light converting means, so that the cost is high and a length for disposing an optical element for enlarging and forming an image is required. It becomes more difficult to reduce the depth.

Further, according to the method shown in FIG. 10, there is a problem that the cost of the light guide band is high.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional problems, and has as its object to provide an image display apparatus which is thin and has a high-definition large-screen display without uneven illuminance.

[0016]

According to another aspect of the present invention, there is provided an image display apparatus comprising: a plurality of image display units arranged in a plane; And a plurality of first optical elements that refract light in a first direction emitted from the image display means to become light in a second direction, and emit light from the first optical element. And a second optical element that refracts the light in the second direction and converts the light in the first direction.

The image display device according to the second aspect is the first aspect.
In the image display device described in the above, the light in the second direction is:
The first image display means may intersect at an equal distance from each of the image display means, or the light emitted from each of the adjacent image display means may have the same end.
The direction is different for each optical element.

The image display device according to the third aspect is the first aspect of the invention.
Or the image display device according to claim 2, wherein
The optical element and the second optical element are characterized in that minute prisms are arranged in an array.

According to the image display device of the present invention, the first direction light emitted from the image display means is refracted into the second direction light which is arranged corresponding to each of the image display means. By providing a plurality of first optical elements and an optical element for refracting light in the second direction emitted from the first optical element to generate light in the first direction, an imaging system is provided. Since it is not used and an expensive light guide band is not used, an inexpensive and thin image display device can be obtained.

Further, the light in the second direction is crossed at an equal distance from each of the image display means, or the first direction is such that the ends of the light emitted from the adjacent image display means coincide with each other. Since the directions are different for each of the optical elements, it is possible to obtain an image display device with no uneven illuminance in the image.

Further, since the first optical element and the second optical element have micro prisms arranged in an array, the thickness of the image display device can be reduced.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a cross-sectional view schematically illustrating an image display device according to the present invention, FIG. 2 is a plan view illustrating a method of combining liquid crystal display devices, FIG. 3 is an explanatory diagram illustrating refraction of light in the image display device, 4 is an explanatory diagram for further explaining refraction of light in the image display device, FIG. 5 is an explanatory diagram for explaining a normal light source, and FIG. 6 is an explanatory diagram for explaining a light source having strong directivity.

As shown in FIG. 1, in the present embodiment, a liquid crystal display device 11 for displaying an image by modulating light from a light source 10 is used as an image display means constituting the image display device. A CRT, a plasma display, or the like may be used as the image display means. Hereinafter, a case where the liquid crystal display device 11 is used as the image display means will be described as an example.

The liquid crystal display panel constituting the liquid crystal display device 11 has three pixels of R, G and B.
Pixel pitch of pixels is 330 μm × 330 μm, number of pixels is 6
For example, as shown in FIG. 2, a liquid crystal display device 11 having a size of 40.times.480 is used to perform a large screen display by combining four liquid crystal display devices 11 in a plane. Each liquid crystal display device 11 has an image display unit 1
9 and a non-image display unit 20 around the image display unit 19.

On the side of the liquid crystal display device 11 opposite to the light source 10, a first micro prism array 12 as a first optical element is arranged so as to correspond to the image display section 19 of each liquid crystal display device 11. The second micro prism array 13 as a second optical element is arranged at a predetermined distance from the first micro prism array 12 to constitute an image display device.

The first micro prism array 12 allows light emitted from each liquid crystal display device 11 in a direction perpendicular to the display surface to intersect at an equal distance from each liquid crystal display device 11 or to be adjacent to each other. The first micro prism array 12 is refracted in different directions so that the ends of the light emitted from the display device 11 coincide with each other.

Each of the second micro prism arrays 13 has a first
The light emitted in different directions from the micro prism array 12 is refracted so as to be all light in the direction perpendicular to the display surface.

The predetermined distance between the first micro prism array 12 and the second micro prism array 13 may be appropriately selected according to the angle at which the first micro prism array 12 refracts light. The light emitted from the micro prism array 12 in different directions may be incident on the second micro prism array 13 without overlapping each other.

With this configuration, the light emitted from the second micro prism array 13 and directed in the direction perpendicular to the display surface does not project on the non-image display section 20, and a seamless large-screen display is performed. Will be able to do it.

Here, as shown in FIG. 3, when the width of the non-image display section 20 is x and the distance between the first micro prism array 12 and the second micro prism array 13 is y, each liquid crystal display Light emitted from the device 11 in the direction perpendicular to the display surface is directed to the first micro prism array 12 in the direction of the angle α that satisfies α = tan ⁻¹ (x / y).
Is refracted by The light traveling in the direction of the angle α is refracted by the second micro prism array 13 in a direction perpendicular to the display surface. In this way, the light emitted from the plurality of liquid crystal display devices 11 can perform a seamless large-screen display.

A more detailed description will be given with reference to FIGS. The non-image display section 20 has a width of 20 mm (the non-image display section of each liquid crystal display 11 has a width of 10 mm), and the distance between the exit surface 14 of the first micro prism array 12 and the entrance surface of the second micro prism array 13. Is 50 mm.

The first micro prism array 12 is provided with micro prisms having an angle θ with respect to the display surface of the liquid crystal display device 11, and the light incident on the first micro prism array 12 Is shifted from the vertical by an angle θ. The light emitted from the emission surface 14 is
The light is refracted by the first micro prism array 12 and is emitted with an angle φ shifted from the perpendicular to the emission surface 14.

When the refractive index of the first micro prism array 12 is n, (sin φ) / (sin θ) = n is established between incident light and outgoing light according to Snell's law.

The light emitted from the first micro prism array 12 is incident on the second micro prism array 13, is refracted by the second micro prism array 13,
, So that all the lights emitted from the micro prism array 13 are in the same direction (the direction perpendicular to the display surface).
The incident angle of light on the second micro prism array 13 is
The emission angle is set to be shifted from the perpendicular to the incident surface of the second micro prism array 13 by an angle θ so as to be shifted from the perpendicular to the incident surface of the second micro prism array 13 by an angle φ.

That is, in the first micro prism array 12 and the second micro prism array 13, the incident angle and the outgoing angle of light may be reversed. In this way, the light incident on the first micro prism array 12 and the light emitted from the second prism array 13 travel in the same direction.

In this embodiment, the first micro prism array 12 and the second micro prism array 13 are formed of polycarbonate having a refractive index n = 1.585, and the first micro prism array 12 and the second micro prism array 12 are formed. Prism array 13
Is set so that the distance between the and is 50 mm. As described above, the width of the non-image display section 20 of each liquid crystal display device 11 is 1
0 mm.

In order to perform a seamless large-screen display,
In each liquid crystal display device 11, the image must be shifted by 10 mm. Therefore, if the above equation (sin φ) / (sin θ) = n is used, then (sin φ) / (sin θ) = 1.585, θ + φ = 90−tan ⁻¹ (10/50), and θ = 4.4 is obtained. Thus, the angle of the teeth of the first micro prism array 12 and the second micro prism array 13 is set to 4.4.
If it is set every time, a seamless large-screen display can be performed.

In the present invention, as the light source 10, FIG.
As shown in the figure, a normal light source 1 that emits light over the entire inside of a hemisphere
When 0 is used, the emission direction and intensity of light are isotropic, but, for example, as shown in FIG. A bright image can be obtained.

When a part of the images of the adjacent liquid crystal display devices 11 is overlapped, when the large screen display is viewed from an oblique direction, the actually viewed image is not the image viewed from the front, but overlaps. You will see the image,
The viewing angle of the image can be widened.

In this embodiment, polycarbonate is used as the material of the first micro prism array 12 and the second micro prism array 13. However, other materials such as transparent resin for optical element such as acrylic resin or glass. It is also possible to form with a material.

Further, if parallelism regulating means represented by a view control plate made by Sumitomo Chemical Co., Ltd. is provided on the emission side of the light source 10 or the emission side of the second micro prism array 13, the liquid crystal display device 11 A brighter large-screen display can be performed without lowering the resolution of the image.

[0042]

As described above, according to the image display device of the present invention, the first direction light emitted from the image display means is refracted by being arranged corresponding to each of the image display means. A plurality of first optical elements that emit light in the second direction, and an optical element that refracts light in the second direction emitted from the first optical element to generate light in the first direction. With this configuration, since an imaging system is not used and an expensive light guide band is not used, a seamless large-screen display can be obtained with an inexpensive and thin image display device.

Further, the light in the second direction intersects at an equal distance from each of the image display means, or the first direction so that the ends of the light emitted from the adjacent image display means coincide with each other. Since the directions are different for each optical element, it is possible to obtain an image display device capable of performing a seamless large-screen display without uneven illuminance in an image.

Further, since the first optical element and the second optical element have micro prisms arranged in an array, the image display device as described above can be easily made thin.

[Brief description of the drawings]

FIG. 1 is a sectional view schematically showing an image display device according to the present invention.

FIG. 2 is a plan view illustrating a method of combining liquid crystal display devices.

FIG. 3 is an explanatory diagram illustrating refraction of light in the image display device.

FIG. 4 is an explanatory diagram for further explaining refraction of light in the image display device.

FIG. 5 is an explanatory diagram illustrating a normal light source.

FIG. 6 is an explanatory diagram illustrating a light source having strong directivity.

FIG. 7 is a plan view showing a liquid crystal display device.

FIG. 8 is a plan view showing a large-screen display device configured by combining a plurality of liquid crystal display devices.

FIG. 9 is an explanatory diagram showing a projection method for performing a conventional large-screen display.

FIG. 10 is an explanatory diagram showing a method using a light guide band for performing a large-screen display.

FIG. 11 is an explanatory diagram showing another method for performing a large-screen display.

[Explanation of symbols]

 Reference Signs List 10 light source 11 liquid crystal display device 12 first minute prism array 13 second minute prism array 14 emission surface 15 liquid crystal display panel 16 PWB 17 TCP 18 driver LSI 19 image display unit 20 non-image display unit 21 lamp 22 condenser lens 23 projection Lens 24 Projection type liquid crystal display device 25 Screen 26 Light guide band bundle 27 Condensing lens 28 Imaging lens 29 Magnifying lens

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI G09F 9/40 G09F 9/40 B (72) Inventor Hiroshi Hamada 22-22 Nagaikecho, Abeno-ku, Osaka-shi, Osaka

Claims (3)

[Claims] 1. A plurality of image display means arranged in a plane, and arranged corresponding to each of the image display means,
A plurality of first optical elements for refracting light in a first direction emitted from the image display means to generate light in a second direction;
An image display device, comprising: a second optical element that refracts the light in the second direction emitted from the first optical element and makes the light in the first direction. 2. The light in the second direction intersects at equal distances from each of the image display means,
2. The image display device according to claim 1, wherein the first optical element has a different direction so that ends of light emitted from the adjacent image display units coincide with each other. 3. 3. The image display device according to claim 1, wherein the first optical element and the second optical element have micro prisms arranged in an array. .