JPH08160416A - Multi-display device and its display unit - Google Patents

Abstract

PURPOSE: To realize a multi-display device which improves the efficiency of utilizing light sources. CONSTITUTION: Plural pieces of display units which are formed by setting the light emission regions of the light sources of the individual display units sufficiently longer than the display regions of transmission type display panels and projecting electrode parts to the outside of casings and are so formed that the electrode projecting electrode parts overlap on each other when plural pieces of these display units are arranged in a matrix form. The respective display units 26, 26', 26" are provided thereon with erecting unmagnified imaging means 27 and enlarged imaging means 30.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multi-display device and its display unit.

In recent years, direct-viewing type such as CRT is currently in use for public use such as public facilities such as public offices, museums, museums, hotels, event halls, amusement parks, etc. to provide images to a large number of viewers indoors and outdoors. There is an increasing demand for large-screen image devices that cannot be manufactured.

As a main large-screen image device that meets such a demand, a projection-type display device for enlarging and projecting and displaying an image on a screen, and a multi-screen for arranging a plurality of small display units in a matrix to increase a screen size are provided. Examples include display devices. Since the multi-display device has a matrix arrangement of small display units, it is possible to reduce the depth with respect to the screen size and make it thinner compared with the magnifying projection type device, but on the other hand, the frame around the screen of each display unit has a multi-display. It has the drawback of becoming a grid-like joint on a large screen.

Therefore, as a method of taking advantage of the thinness and minimizing the seam, as shown in FIG. 7, an erecting image forming lens array and a Fresnel lens array using a microlens array or the like in a transmissive display unit such as an LCD. A multi-display method has been proposed in which a plurality of short-path optical projection optical systems made up of lenses are combined and a plurality of display screens are arrayed on the same screen by slightly enlarging them so as to sufficiently include a frame.

[0005]

2. Description of the Related Art FIG. 7 shows a conventional multi-display device. In FIG. 7, 1 is a backlight unit, 2 is a transmissive display panel (LCD or the like), and 3 and 4 are microlens arrays, which are a combination of two. An erecting equal-magnification image is formed, and 5 is a concave Fresnel lens that magnifies the erecting equal-magnification image and projects it seamlessly on one screen 6 to display one large screen. is there.

In the above multi-display device, L
Although a transmissive display panel such as a CD requires a light source,
A thin tubular light source such as a cathode tube is generally used as a light source so as not to impair the feature of being thin. Further, since a large amount of light is required to obtain the display screen brightness, a large number of these light sources are arranged side by side in a raft.

As shown in FIG. 8, such a cathode tube 7 has electrode portions 8 at both ends of the light emitting portion. Since the electrode portion 8 is a non-light emitting area, the display area of the LCD panel is uniform. In order to illuminate with a sufficient brightness, a cathode tube whose light emitting area 10 of the light source 7 is sufficiently long with respect to the display area 9 of the LCD panel 2 as shown in FIG. 9 is used, or as shown in FIG. It is necessary to use the light source 7 having a short light emitting area and the means 11 for expanding the light emitting area in accordance with the display area in combination.

In FIG. 10, a curve A shown by a solid line is a display luminance distribution when there is no means 11 for expanding the light emitting area, and a curve B shown by a chain line is a luminance distribution when there is a means 11 for expanding the light emitting area. .

In a multi-display device in which a transmissive display panel is combined with a short optical path optical system, theoretically, the light emitting area of the light source is made sufficiently longer than the display area, and
The magnifying power of the optical system should be set so that the projected image can be magnified to a size that includes the electrode part sufficiently. However, if the magnifying power is increased, the resolution of the displayed image decreases, and Display quality problem that the brightness ratio becomes large,
A structural problem arises that the device thickness increases. Therefore, in practice, the light emitting area of the light source is set shorter than the display area and combined with the light emitting area expanding means.

[0010]

As a means for expanding the above-mentioned light emitting region, for example, as shown in FIG. 11, the diffuser plate 12 is made thick by making the central portion of the light source thicker and making it thinner toward the end portion. There is a method for making the amount of emitted light of the light uniform.

In this method, since most of the light rays are reflected back to the light source side by the diffuser plate 12, the light emitting areas of the diffuser plate 12 and the light source 7 are put in the closed reflecting surface 13, and the reflected light is again diffused. It adopts a method of converting into emitted light. Then, in order to reduce the loss, both the diffusion plate 12 and the reflection surface 13 are made of a material having a small light absorption, but the light absorption rate is not completely zero, and the light beam repeats between the diffusion plate 12 and the reflection plate 13. Since the number of reflections is very large, a considerable amount of light rays are eventually absorbed by the diffusion plate 12 and the reflection plate 13, resulting in a reduction in light source utilization efficiency.

In view of the above-mentioned conventional problems, the present invention intends to realize a multi-display device with improved light source utilization efficiency.

[0013]

According to the display unit of the present invention, both ends of the thin tubular light source 23 project outside the display unit housing 20, and the light source 23 is the light source 23.
Light source units 24 arranged at intervals sufficiently wider than the diameter of
And a transmissive display panel 21 in combination, or both ends of a thin tubular light source 23 project outside the display unit housing 20 and the light source 23 is
The light source units 24 are arranged in rows, and the upper and lower rows are arranged in a zigzag pattern, and the transmissive display panel 21 is combined, or both ends of the thin tubular light sources 23 are arranged in the display unit casing. It is characterized in that a light source unit 24 projecting to the outside of the body 20 and having its light source 23 arranged obliquely or in parallel to the light emitting surface of the unit and a transmissive display panel 21 are combined.

Further, the multi-display device of the present invention is characterized in that a plurality of the display units are arranged in a matrix. Further, an erecting equal-magnification image forming means 27 and a magnifying image forming means 30 are mounted on the display unit,
It is characterized in that a plurality of units are arranged in a matrix and an image is formed on a single screen 31 for large-screen display. By adopting this configuration, it is possible to obtain a multi-display device with improved light source utilization efficiency.

[0015]

According to the present invention, the light emitting region of the light source of each display unit is set sufficiently longer than the display region, the electrode portion is projected to the outside of the unit casing, and when a plurality of the display units are arranged, each protruding electrode is arranged. By making the parts fit together well, the light emitting area is expanded as compared with the conventional one, and therefore, the light emitting area expanding means is not required, so that the light source use efficiency is not deteriorated and the multi-display device is configured. Since the frame width is practically small, it is not necessary to increase the magnification of the short optical path magnifying optical system.

[0016]

1 is a view showing a first embodiment of a display unit of the present invention, (a) is a partial sectional plan view, (b) is a partial sectional front view, and (c) is a side view. is there. In the figure, 20
Is a casing of the display unit, and the casing 20 is provided with an LCD panel 21 on the upper part and a reflecting surface 22 on the lower part. A plurality of thin-tube light sources (cold-cathode tubes) 23 are provided between the LCD panel 21 and the reflecting surface 22 to form a light source unit 24. And light source 2
The light emitting regions 3 are arranged so that their light emitting regions are sufficiently longer than the display region of the LCD panel and are arranged at sufficiently wide intervals (combinable intervals as shown in FIG. 2 described later) in comparison with the tube diameter.
3 a projects from the housing 20 and is covered with a case 25.

In this embodiment having such a configuration, a plurality of units can be arranged in a matrix to form a multi-display device. At that time, as shown in FIG. 2, the case 25 covering the electrode portions of the adjacent first display unit 26 and second display unit 26 'can be combined with each other. The second display unit 26 'is obtained by horizontally rotating the first display unit 26 by 180 °. In this way, the display units 26, 26 '
By combining the above, the arrangement density of the display units can be increased. Further, since the light emitting area of the light source of each unit is sufficiently longer than the display area of the LCD panel, the light emitting area expanding means is not required, and the light source utilization efficiency can be improved.

FIG. 3 is a view showing a second embodiment of the display unit of the present invention, (a) is a plan view, (b) is a partial sectional front view, and (c) is a side view. In the figure, 20 is a housing of the display unit, and the housing 20 has an LCD on top.
A panel 21 is provided, and a reflecting surface 22 is provided on the bottom. A plurality of thin tubular light sources (cold-cathode tubes) 23 are provided between the LCD panel 21 and the reflecting surface to form a light source unit 24.

The light emitting area of the light source 23 is L
A CD panel having a length sufficiently longer than the display area is used, and the upper and lower rows are arranged in a staggered manner in two rows above and below. The electrode portion 23 a is projected from the housing 20 and is covered with the case 25.

In this embodiment having such a configuration, a plurality of units can be arranged in a matrix to form a multi-display device. At that time, the case 25 arranged in a zigzag pattern covering the electrode portions can be combined with the adjacent units, so that the arrangement density of the display units can be increased as in the previous embodiment. Further, since the light emitting area of the light source of each unit is sufficiently longer than the display area of the LCD panel, the light emitting area expanding means is not required, and the light source utilization efficiency can be improved. Further, in this embodiment, the light sources can be arranged at a higher density than in the first embodiment in the same housing as the first embodiment.

4A and 4B are views showing a third embodiment of the display unit of the present invention. FIG. 4A is a plan view and FIG. 4B is a view b in FIG.
A cross-sectional view taken along line -b, and (c) is a side view. In the figure, reference numeral 20 denotes a housing of the display unit.
The LCD panel 21 is provided on the upper part of the and the reflective surface 22 is provided on the lower part. In the middle of the LCD panel 21 and the reflecting surface 22, a plurality of thin-tube light sources (cold-cathode tubes) 23 having a light-emitting area sufficiently longer than the display area of the LCD panel are provided.
Are all inclined in the same direction, and the electrode portion 23
a projects from the housing 20 and is covered by the case 25.

In this embodiment having such a configuration, a plurality of units can be arranged in a matrix to form a multi-display device. At that time, the case 25 covering the electrode part
However, since the one end of the housing 20 is provided on the upper side and the other end is provided on the lower side, they can be stacked vertically as shown in FIG. 4B, and the display unit arrangement density is increased. be able to. Further, since the light emitting area of the light source of each unit is sufficiently longer than the display area of the LCD panel, the light emitting area expanding means is not required, and the light source utilization efficiency can be improved. Further, in this embodiment, the light sources can be arranged in the housing with high density as in the second embodiment.

5A and 5B are views showing a fourth embodiment of the display unit of the present invention. FIG. 5A is a plan view and FIG. 5B is a view b in FIG.
A cross-sectional view taken along line -b, and (c) is a side view. In the figure, reference numeral 20 denotes a housing of the display unit.
The LCD panel 21 is provided on the upper part of the and the reflective surface 22 is provided on the lower part. Further, in the middle of the LCD panel 21 and the reflecting surface 22, as shown in FIG. 2B, a plurality of thin tubular light sources (cold-cathode tubes) 23 having a light emitting area sufficiently longer than the display area of the LCD panel are provided. The electrodes 23 a are arranged side by side in the upper part or the lower part between the LCD panel 21 and the reflecting surface 22, and the electrode parts 23 a project from the housing 20 and are covered with the case 25.

In this embodiment having the above-mentioned structure, a plurality of light sources are arranged in a matrix so that a light source arranged on the upper side and a light source arranged on the lower side are adjacent to each other to form a multi-display device. can do. By arranging in this way, the arrangement density of the display units can be increased. The light emitting area of the light source of each unit is L
Since it is sufficiently longer than the display area of the CD panel, the light emitting area expanding means is unnecessary and the light source utilization efficiency is improved. Further, in this embodiment, the light sources can be arranged in the housing with high density as in the previous embodiment.

In this embodiment, the light quantity illuminating the LCD panel is different between the unit in which the light source is arranged on the upper side and the unit in which the light source is arranged on the lower side. Can be provided, or the arrangement density of the light sources can be roughened.

FIG. 6 is a diagram showing an embodiment of the multi-display device of the present invention. In the figure, 26, 26 ',
26 "is a display unit, and any of the display units of the above-described first to fourth embodiments can be used as the display unit.
Two microlens arrays 2 are provided above 6'and 26 ".
An erecting equal-magnification image forming unit 27 including 8 and 29 and a magnifying image forming unit 30 including a Fresnel lens are provided.

In this embodiment having such a configuration, the display of each display unit 26, 26 ', 26 "is enlarged and projected seamlessly on the screen 31 arranged at the image forming position of the enlarged image forming means 30. It is possible to display a large screen, and in this embodiment, since the electrode portions of the respective display units are overlapped with each other to have a substantially small frame width, it is not necessary to increase the enlargement ratio of the short optical path enlargement optical system. The brightness of the screen can be improved.

[0028]

According to the present invention, the display brightness can be improved by eliminating the loss due to the expansion means of the light emitting area and lengthening the light emitting area itself of the light source. Regarding the loss due to the light emitting area expanding means, when the necessary light emitting area is 226 mm, the light emitting area of the light source is 210 mm, and when the light emitting area expanding means using the diffusion plate is used and not used, the emitted light amount is It improved by about 40%.

Regarding the length of the light emitting area of the light source,
Considering that the light emitting area of the cathode tube can be changed from 210 mm to 226 mm, an improvement of about 8% can be obtained from the ratio of the light emitting area. The total of the above two effects is 30-50
% Improvement in display brightness can be expected.

[Brief description of drawings]

FIG. 1 is a view showing a first embodiment of a display unit of the present invention, (a) is a partially sectional plan view, (b) is a partially sectional front view, and (c) is a side view.

FIG. 2 is a diagram showing an arrangement state of the first embodiment of the display unit of the present invention.

3A and 3B are views showing a second embodiment of the display unit of the present invention, FIG. 3A is a plan view, FIG. 3B is a partially sectional front view, and FIG.
Is a side view.

4A and 4B are views showing a third embodiment of the display unit of the present invention, FIG. 4A is a plan view, FIG. 4B is a sectional view taken along line bb in FIG. 4A, and FIG. Is.

5A and 5B are views showing a fourth embodiment of the display unit of the present invention, FIG. 5A is a plan view, FIG. 5B is a sectional view taken along line bb in FIG. 5A, and FIG. Is.

FIG. 6 is a diagram showing a multi-display device of the present invention.

FIG. 7 is a diagram showing a conventional multi-display device.

FIG. 8 is a diagram showing a cathode tube as a light source.

FIG. 9 is a diagram showing a conventional transmissive display unit.

FIG. 10 is a view showing a display unit having a conventional light emitting area expanding unit.

FIG. 11 is a view showing a display unit having a conventional light emitting area expanding unit.

[Explanation of symbols]

 20 ... Housing 21 ... LCD panel 22 ... Reflecting surface 23 ... Light source 23a ... Electrode part 24 ... Light source unit 25 ... Case 26, 26 ', 26 "... Display unit 27 ... Erecting equal-magnification image forming means 28, 29 ... Micro Lens array 30 ... Enlarging image forming means 31 ... Screen

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yukio Iigahama 1015 Kamiodanaka, Nakahara-ku, Kawasaki-shi, Kanagawa Within Fujitsu Limited (72) Inventor Hisa Yamaguchi 1015 Kamedotaka, Nakahara-ku, Kawasaki-shi, Kanagawa Fuji Stock In the company

Claims (7)

[Claims] 1. Both ends of a thin tubular light source (23) project to the outside of a display unit housing (20), and the light source (2)
3) A display unit characterized by comprising a light source unit (24) arranged at an interval wider than the diameter of the light source (23) and a transmissive display panel (21). 2. Both ends of the thin tubular light source (23) project to the outside of the display unit housing (20), and the light source (2)
3) are arranged in two stages, and a light source unit (24) in which the upper and lower stages thereof are arranged in a staggered manner, and a transmissive display panel (2).
A display unit characterized by being combined with 1). 3. A thin tubular light source (23) has both ends projecting to the outside of the display unit housing (20) and the light source (2).
A display unit characterized in that 3) is formed by combining a light source unit (24) arranged obliquely or in parallel with a light emitting surface of the unit and a transmissive display panel (21). 4. A multi-display device comprising a plurality of the display units according to claim 1 arranged in a matrix. 5. A multi-display device comprising a plurality of display units according to claim 2 arranged in a matrix. 6. A multi-display device comprising a plurality of display units according to claim 3 arranged in a matrix. 7. The multi-display device according to claim 4, 5 or 6, wherein an erecting equal-magnification image forming means (27) and a magnifying image forming means (30) are mounted on each display unit, and a plurality of them are arranged in a matrix. A multi-display device characterized in that a large screen is displayed by arranging the units and forming an image on one screen (31).