JPH08160892A - Surface light emitting display device - Google Patents

Abstract

PURPOSE: To make it possible to reduce the thickness over the entire part of a display device, to reduce its running cost and to save the labor for maintenance by a lamp life. CONSTITUTION: The surface of a light transmission plate 1 consisting of a translucent plate of an acrylic resin, etc., is provided with dot pattern-shaped light emitting layers 4 of a higher ratio to release light outside the furtherer from LEDs 5 arranged on one side of the light transmission plate 1. The light from the LEDs 5 is once radiated uniformly over the entire surface of the pattern display part A of the light transmission plate 1 and thereafter, the unnecessary light is returned into the light transmission plate 1 according to the patterns of characters and designs plotted on the pattern filter 3 on the light emitting layers 4, by which the necessary characters and designs are made to relief on the surface.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surface emitting type display device used for advertisements, signboards and the like.

[0002]

2. Description of the Related Art Conventional display devices used for advertisements, signboards, etc. are made of acrylic resin, PV, or the like, as shown in FIG.
Plate-shaped cover 1 made of C (polyvinyl chloride), etc.
01 is a frame 102 made of a strong material such as an iron plate
Supported on the surface of the cover 101 by directly printing necessary characters and designs on the surface of the cover 101 or by attaching a film on which the characters are printed.
One or several 03 are arranged so that the entire cover 101 is exposed from the inside so that characters and designs on the surface are highlighted. Incidentally, 104 is a cathode fluorescent lamp 10.
3 is a control board.

[0003]

However, the conventional display device as shown in FIG. 3 has a cathode fluorescent lamp 1 inside.
03, the total thickness is at least 100.
The problem of becoming thicker than mm, and the cathode fluorescent lamp 10
Since the power consumption of No. 3 is about 30 W, there is a problem that the running cost becomes high. In addition, the configuration using the cathode fluorescent lamp 103 has a problem that the lamp life is short, at most, about 5000 hours, and maintenance is troublesome.

In view of the above problems, the present invention is capable of reducing the overall thickness, reducing running costs, and reducing maintenance work due to lamp life.
It is an object of the present invention to provide a display device capable of realizing the above.

[0005]

According to another aspect of the present invention, there is provided a surface light emitting display device comprising a light transmissive plate material, and a light guide plate through which light is propagated in the light transmissive plate material along a surface direction. An LED arranged at an arbitrary position in the light propagation direction of the light guide plate, a light emitting layer provided on at least one of the front surface and the back surface of the light guide plate, and having a light reflecting portion that diffusely reflects light, and the light emitting layer. A pattern layer disposed on the surface opposite to the surface provided with, and having a region that reflects light and a region that transmits light according to an arbitrary pattern such as characters and designs. .

A surface emitting display device according to a second aspect is the device according to the first aspect, in which the light emitting layer has a lower light reflectance near the LED and a higher light reflectance as the light emitting layer is farther from the LED. It is characterized by having.

A surface emitting display device according to a third aspect is the device according to the first aspect, wherein an LED fixing holder having light reflectivity is provided on at least an inner surface side, and the LED is accommodated in the LED fixing holder. Is characterized by.

[0008]

In the surface emitting display device according to the first aspect, the light emission according to the character and the design can be seen as follows. The light output from the LED arranged at an arbitrary position in the light propagation direction of the light guide plate first propagates in the light guide plate along the surface direction. Normally, when light is propagated in the light guide plate along the surface direction of the light guide plate (translucent plate material), the light is propagated while being mirror-reflected on the front and back surfaces of the light guide plate. When the incident angle of the light that hits the front and back surfaces is small, the light that hits the front and back surfaces is emitted to the outside of the light guide plate, and the light with a large incident angle is specularly reflected and propagates along the surface direction of the light guide plate. A light emitting layer is provided on at least one of the front surface and the back surface of the light guide plate, and the light emitting layer has a light reflecting portion that diffusely reflects light.

When the light propagating along the surface direction of the light guide plate hits the light reflecting portion of the light emitting layer as described above, the light is diffusely reflected here, and a part of the light is emitted to the facing surface (for example, the back surface). It enters at a small angle of incidence with respect to the surface (if a layer is provided) and is emitted from the facing surface to the outside. As a result, when viewed from the facing surface of the light emitting layer, light is radiated over the entire surface.

A pattern layer is further provided on the upper surface of the light emitting layer. The pattern layer is provided with a region that reflects light and a region that transmits light according to a pattern such as characters and designs, and the light emitted through the light emitting layer hits the pattern layer. Then, the light that hits the light-transmitting region of the pattern layer is directly emitted to the outside, but the light that hits the light-reflecting region is reflected and returns to the inside of the light guide plate. When the pattern layer is formed, a region, such as a character or a design, which is desired to emit light is configured to transmit light, and a peripheral portion thereof is configured to reflect light. As a result, light emission display is performed according to the characters and design on the pattern layer.

The pattern layer is formed by directly drawing and printing a pattern on the upper surface of a light guide plate or a light emitting layer, or by drawing and printing a pattern on a transparent member made of a transparent plate material or film. It can be configured by fixing it on the light emitting layer by a method such as pasting. By doing so, even when the signboard and the advertisement are single, the light guide plate and the light emitting layer can be used also as those used for other signboards and advertisements, and by changing the pattern layer, arbitrary characters and designs can be obtained. It can display billboards and advertisements.

In the surface emitting display device according to the second aspect, the light emitting layer has a gradation pattern, and the light reflectance is lower near the LED and higher as the distance from the LED increases. As a result, in the vicinity of the LED, light easily enters the light guide plate surface at a large angle and is difficult to be radiated to the outside. On the contrary, if the light is separated from the LED, the light is diffusely reflected and enters the light guide plate surface at a small angle to the outside. It becomes easy to be radiated. On the other hand, in the light guide plate, the amount of light is higher near the LED, and the amount of light decreases as the distance from the LED increases. Due to such a relationship between the variation of the light emissivity on the surface of the light emitting layer and the variation of the amount of light in the light guide plate, the light emission amount is almost constant over the entire light emitting layer, and the unevenness of the brightness on the entire surface of the light guide plate. Can be prevented.

In the surface emitting display device according to the third aspect of the invention, since the inner surface side of the LED fixing holder holding the LED is configured to reflect light, the light output from the LED is efficiently directed to the light guide plate side. Is less likely to be wasted and light is wasted.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. 1A and 1B are views showing the configuration of a surface emitting display device according to an embodiment of the present invention. FIG. 1A is a partial plan view of the device, and FIG. 1B is a partial sectional view of the device. . Also,
FIG. 2 is a diagram showing a light propagation state in the device.

The surface emitting display device includes a light guide plate 1 having a plate shape, an LED fixing holder 2 fitted in an end portion of the light guide plate 1, and a pattern filter (pattern layer) attached on the surface of the light guide plate 1. Have three. In addition, a frame 7 may be provided on the peripheral surface of the light guide plate 1 as needed.

The light guide plate 1 is made of a highly translucent material such as acrylic resin, and in the case of a single-sided display in which a signboard, an advertisement, etc. are highlighted only on one side, only one of the front and back sides is displayed. The light emitting layer 4 is formed, and the pattern filter 3 is provided on the surface opposite to the surface on which the light emitting layer 4 is formed. Further, in the case of double-sided display in which a signboard, an advertisement or the like is displayed on both front and back surfaces, the light emitting layer 4 is formed on both the front surface and the back surface, and the pattern filter 3 is provided on the upper surface of the light emitting layer 4. The configuration examples shown in FIGS. 1 and 2 are for double-sided display, and the light emitting layer 4 (the back surface side light emitting layer 41, the front surface side light emitting layer 42) and the pattern filter 3 (the front surface side pattern filter 31, the back surface side) are provided on both sides. A pattern filter 32) is provided. The light emitting layer 4 is shown in FIG.
As shown in (A), it is composed of a dot pattern provided in the pattern display area A which is set substantially in the center of the light guide plate surface, and each dot portion (light reflecting portion) 4a (41).
a, 42a) is formed by screen-printing a paint that diffusely reflects light. When the paint that diffusely reflects light is printed on the back surface of the light guide plate 1 in this way, the light that hits the dot portions 4a from the inside of the light guide plate 1 is diffusely reflected here and returned to the inside of the light guide plate 1, and a part of the light Enters at a small incident angle with respect to the facing surface (surface) and is emitted to the outside.

As shown in FIG. 1A, the dot pattern of the light emitting layer 4 is configured so that it is smaller near the LED fixing holder 2 (LED5) and larger as it is farther from the LED 5. As a result, it is difficult for light to hit the dot portions 4a of the light emitting layer 4 in the vicinity of the LED 5, and the rate of light emitted to the outside is low (low light transmittance). Therefore, the attenuation rate of the light propagated in the propagation direction becomes low, and a large amount of light is guided to the position away from the LED 5. On the contrary, when the distance from the LED 5 increases, the size of the dot portion 4a increases, so that light is emitted from the dot portion 4a.
It becomes easy to hit a and the amount of diffused reflection increases, so that it is easily radiated to the outside (high light transmittance). As a result, LE
The total amount of light on the surface of the light emitting layer 4 becomes substantially constant regardless of the position near / away from D5. The light emitting layer 4
In order to change the light reflectance of the above, the number of dots may be changed in addition to changing the size of the dot portion 4a as described above. That is, the size of each dot is the same, the number of dots is smaller near the LED 5,
The number of dots increases as the distance from 5 increases. Thereby, LE
The light transmittance is lower near D5, and the light transmittance is higher as the distance from D5 increases, and the total light amount on the surface of the light emitting layer 4 becomes substantially constant.

The LED fixing holder 2 is a cap-shaped member that is fitted into one side of the plate-shaped light guide plate 1 and has an LED substrate 6 for mounting the LED 5 therein. The LED substrate 6 is provided so as to be parallel to the thickness of the light guide plate 1 when the cap-shaped LED fixing holder 2 is fitted into one side of the light guide plate 1.
The LED 5 mounted on the substrate 6 faces the thickness portion of the light guide plate 1. A plurality of LEDs 5 are arranged along the side of the light guide plate 1. The inner surface sides 2a and 6a of the LED fixing holder 2 and the LED substrate 5 may be subjected to light reflection processing such as application of white paint or metal plating, so that light is wastefully absorbed and transmitted inside the LED fixing holder 2. There is no such thing. Since the LED fixing holder 2 is often used outdoors, it is preferable that the LED fixing holder 2 is made of a material having good weather resistance, such as AS (acrylonitrile / styrene copolymer) or ABS (acrylonitrile / butadiene).・
A styrene resin such as a styrene copolymer), PC (polycarbonate) or the like is used for molding. In the case of molding with such a resin, by mixing with a light reflecting material such as a white pigment, the resin itself has light reflectivity, and the time and effort for light reflecting processing on the inner surface sides 2a, 6a can be saved. be able to.

The pattern filter 3 is made of a transparent plate material, a film-shaped member, or the like, and a pattern such as a signboard, letters relating to advertisements, or a design is drawn on the surface. The drawn pattern is configured so that the necessary characters, the design part, that is, the characters that need to emerge, and the design part transmit light, and the unnecessary areas, that is, the necessary characters and the surrounding part of the design part reflect light. Is configured to. As a specific configuration example, for example, the necessary characters and the design part are configured to be transparent or to transmit light by applying a translucent paint, and the peripheral part reflects light such as white paint. Apply or print the desired material. When drawing such a character or design, if the pattern is a single one, it is created by drawing the pattern one by one by coating etc., but creating the same pattern many times When doing so, it is possible to collectively create them by a method such as printing.

On the surface of the light guide plate 1, as shown in FIG.
As shown in (A), the pattern display area A is set in the central portion, the light emitting layer 4 is provided only in the pattern display area A, and the other peripheral portion B is configured to specularly reflect light. However, in order to further increase the light reflectivity in the peripheral portion B, a material having light reflectivity, such as white paint or metal plating, is applied to the region 8 corresponding to the peripheral portion B of the pattern filter 3 or the light emitting layer 4. May be given. Thereby, the light reflectivity in the peripheral portion B becomes more reliable.

The pattern filter 3 can be fixed, for example, by applying an adhesive on the back surface and sticking it on the light emitting layer 4 of the light guide plate 1. In that case, the adhesive may be the pattern filter 3 in advance.
It may be applied to the back surface of. Further, as a method of fixing the pattern filter 3, for example, as shown in FIG. 1, a frame 7 made of weather resistant resin such as AS, ABS, PC or metal is formed, and the surface of the light emitting layers 41, 42 is formed. With the pattern filters 31 and 32 placed thereon (in the case of the single-sided emission configuration shown in FIG. 3, the pattern filter 3 is placed on the surface of the light guide plate 1), the frame 7 is fitted and the pattern filter 3 is sandwiched. Other methods such as the method may be used.
When assembling the surface emitting device, after fixing the pattern filter 3 by the above-described method, the LED fixing holder 2 having the LED 5 mounted therein is fitted to a predetermined side of the light guide plate 1.

The operation of light when the LED 5 is turned on in the surface emitting display device constructed as described above will be described with reference to FIG. The LED 5 emits almost three lights as shown.
The light is output in the direction of 60 degrees, but the light is output from the LED fixing holder 2
The light is reflected inside and propagates toward the light guide plate 1. In the light guide plate 1, the light travels between the front and back wall surfaces while being specularly reflected, but when it hits the dot portion 41a of the light emitting layer 41 provided on the back surface side, it is diffusely reflected and goes out from the pattern filter 31 on the front surface side. Is emitted. Further, when it hits the dot portion 42a of the light emitting layer 42 provided on the front surface side, it is diffusely reflected and radiated to the outside from the pattern filter 32 on the back surface side. In the radiation portion on the front surface side, if the pattern of the pattern filters 31 and 32 is a character or a design portion (light transmitting area), light is emitted to the outside as it is,
If it is the peripheral portion (light reflection area) of the character or design portion, the light is reflected by the peripheral portion and returns. By the operation of such light, the characters of the pattern filters 31 and 32 and the pattern according to the design emerge on the surface of the surface-emitting display device. At that time, the dot patterns of the light-emitting layers 41 and 42 are closer to the LED 5 than the light. Since it is configured to have a high reflectance, the characters and the design that emerges have almost the same brightness, and there is no uneven brightness when used as a signboard, an advertisement, or the like.

The pattern layer may be formed by directly drawing or printing on the surface of the light guide plate 1.
For example, by directly applying white paint to the portion corresponding to the light reflection area, it is possible to obtain light emission according to an arbitrary character and design.

Further, although the above-mentioned embodiment is a dual emission type, as shown in FIG. 3, the single-sided emission device can be constructed by providing the emission layer 4 and the pattern layer (pattern filter 3) on only one side. You can also

[0025]

The surface emitting display device according to claim 1 is
The LED is arranged at an arbitrary position in the light propagating direction of the light guide plate, and since the entire thickness is thin enough to substantially correspond to the thickness of the light guide plate, it is possible to reduce the installation space of the display device. it can. Specifically, the thickness can be about 1/5 to 1/10 of that of the conventional device.
In addition, since LEDs are used as light emitting sources, there are advantages that power consumption can be reduced and life can be extended. Specifically, the power consumption is 1 compared to the case of using a cathode fluorescent lamp.
It could be suppressed to about / 10 and the life could be extended to about 50,000 hours. Further, the light emission of the signboard, the arbitrary characters related to the advertisement, etc. and the pattern according to the design is obtained by the pattern layer provided on the facing surface of the light emitting layer, and the light guide plate, the light emission even when the signboard and the advertisement are single. Since the same layer can be used in common, there is an advantage that the manufacturing cost can be kept low.

According to the surface emitting display device of the second aspect, it is possible to obtain substantially uniform brightness on the entire surface of the light guide plate (light emitting layer), and it is possible to obtain a high quality light emitting signboard and advertisement. According to the surface emitting display device of claim 3, LE
The light output from D can be efficiently guided to the light guide plate side, and the light can be effectively used.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of a surface emitting display device according to an embodiment of the present invention.

FIG. 2 is a diagram showing a light propagation state in the device.

FIG. 3 is a diagram showing another embodiment of the present invention, showing a sectional configuration of a light guide plate, a light emitting layer, and a pattern layer portion.

FIG. 4 is a diagram showing a configuration example of a conventional display device.

[Explanation of symbols]

 1 Light guide plate 2 LED fixing holder 3, 31, 32 Pattern filter 4, 41, 42 Light emitting layer 4a, 41a, 42a Dot part 5 LED 6 LED substrate 7 Frame

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Katsushi Watanabe 1310 Kamihachi, Shirane, Niigata Prefecture Sharp Niigata Electronics Co., Ltd.

Claims (3)

[Claims] 1. A light guide plate made of a light-transmissive plate material, through which light propagates in the light-transmissive plate material along a surface direction, and an LE disposed at an arbitrary position in the light propagation direction of the light guide plate.
D, a light emitting layer provided on at least one of the front and back surfaces of the light guide plate and having a light reflecting portion that diffusely reflects light, and a surface disposed opposite to the surface provided with the light emitting layer.
A surface emitting display device comprising: a pattern layer having a region that reflects light and a region that transmits light according to an arbitrary pattern such as a design. 2. The surface emitting display device according to claim 1, wherein the light emitting layer has a gradation pattern having a lower light reflectance near the LED and a higher light reflectance away from the LED. 3. LE having light reflectivity at least on the inner surface side
The D fixed holder is provided, and the LED is attached to the LED fixed holder.
The surface-emitting display device according to claim 1, further comprising: