JP2001168396A - Light emitting display device and light emitting display unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light emitting display device capable of obtaining a clear image by improving a contrast even in the case of a light emitting element having a small light amount. SOLUTION: Three types of LED lamps 3, 4 and 5 for R, G and B are combined to one pixel. A hood 2b surrounding heads 3b, 4b and 5b from four sides of upper, lower, right and left sides is formed by projecting from a front panel 2. A light emitting display unit 2a coated on the inner peripheral surface of the hood 2b with a reflecting material 2d is embedded in a uniform array pattern in the panel 2. Lights irradiated from the LED lamps 3 to 5 are repeatedly reflected on the material 2d of the inner peripheral surface of the hood 2b, and the light is not absorbed by the inner peripheral surface of the hood 2b but taken out, the lights from the lamps 3 to 5 are not attenuated but can be efficiently recovered.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light-emitting display device for displaying a full-color image by arranging a large number of light-emitting elements such as LED lamps and chip LEDs in a matrix. To a light emitting display device and a light emitting display unit.

[0002]

2. Description of the Related Art Light emitting diodes (in the present specification,
A full-color image display using “LEDs” has three LEs of red (R), green (G), and blue (B).
One pixel (dot) by combining the D lamp
The basic structure is to fix a large number of LED displays each having pixels arranged in a matrix in a frame of an image display.

[0003] The LED display has an LED lamp arrayed on the front side and a circuit board connected to a control device on the image display side and connected to the LED lamp on the rear side. In such an LED display, lighting control of each LED lamp is executed based on image data from the display device, and a full-color light emission image is obtained by synthesizing the emission colors of the three primary colors of R, G, and B light.

FIGS. 7A and 7B are schematic views showing a main part of a conventional LED display, in which FIG. 7A is a front view and FIG. 7B is a longitudinal sectional view.

In FIG. 7, a substrate 52 is fixed on the back side of a front panel 51 formed integrally with the peripheral wall of the LED display, and R, G, and B LED lamps 53, 54, and 55 are attached to the front panel 51, respectively. It is fixed through. These LED lamps 53, 54, and 55 are formed by sealing a light emitting element with a resin, as is well known.
a, 54a and 55a. The lead frames 53a to 55a are connected to and fixed to the substrate 52, respectively.

In the case of an outdoor installation type, since sunlight interferes with an image, a hood 51a is usually provided on the front panel 51 so as to protrude. This hood 51a is L
The ED lamps 53 to 55 project from one dot in the vertical direction and are formed over the entire length of the LED display in the width direction. By providing such a hood 51a, it is possible to prevent the sunlight from directly radiating to the LED lamps 53 to 55, and to prevent a change in the hue of the red, green, and blue emission colors. Moreover, interference of light emission between the dots of the LED lamps 53 to 55 arranged vertically is also suppressed.

[0007]

However, FIG.
In, part of the light emitted from the LED lamps 53 to 55 enters the hood 51a, a part of which is reflected, and the other part is absorbed. In particular, the LED lamp 53
When the hood 51a is black so that the LED display looks black when no light is emitted from any of the components 55 to 55, most of the light incident on the hood 51a is absorbed without being reflected.

That is, since tens of percent of the light emission amount of the LED lamps 53 to 55 is absorbed by the hood 51a, the image obtained by the LED display indicates the light emission amount of the LED lamps 53 to 55. It is not fully utilized, and a light-emitting element with a small amount of light has insufficient contrast.

In view of the above, the present invention provides a light emitting display device and a light emitting display unit capable of improving a contrast and obtaining a clear image even with a light emitting element having a small light amount.

[0010]

According to the present invention, a hood surrounding a light emitting portion of a light emitting diode is formed so as to protrude from a display surface, and a reflective material is provided on an inner peripheral surface of the hood, so that light radiated from the light emitting diode is provided. Is reflected on the inner peripheral surface of the hood.

[0011] This makes it possible to efficiently extract the light emitted from the light emitting diode to the outside of the hood, and to improve the contrast and obtain a clear image even with a light emitting element having a small amount of light.

[0012]

According to the first aspect of the present invention, in a light emitting display device in which light emitting portions of light emitting diodes are arranged on a display surface, a hood surrounding the light emitting portion is formed so as to protrude from the display surface. A light-emitting display device characterized in that a reflective material is provided on the inner peripheral surface of the hood, wherein light emitted from the light-emitting diode is reflected by the reflective material on the inner peripheral surface of the hood, Light can be extracted efficiently. Therefore, a clear image can be obtained by improving the contrast even with a light emitting element having a small amount of light.

According to a second aspect of the present invention, there is provided the light emitting display according to the first aspect, wherein a length of the hood protruding from the display surface is set to 50% or more of an opening width of the hood. Direct light radiated from the diode can be radiated up to 45 °, and at a larger angle, radiated as light reflected by the reflector on the inner peripheral surface of the hood.

According to a third aspect of the present invention, there is provided the light emitting device according to the first or second aspect, wherein one pixel for full-color light emission constituted by combining the light emitting diodes is one unit, and the hood surrounds the one unit. This is a display device, and light emitted from a plurality of light emitting diodes constituting one pixel can be reflected by a reflector on the inner peripheral surface of the hood and mixed and extracted in one unit. And the contrast can be further improved.

According to a fourth aspect of the present invention, there is provided a light-emitting display unit for full-color light emission in which one pixel is formed by combining three kinds of light-emitting diodes having red, green, and blue light emission colors, respectively. A light-emitting display unit comprising a hood surrounding all the light-emitting portions, and further including a reflective material on an inner peripheral surface of the hood;
Light emitted from a plurality of light-emitting diodes constituting pixels can be reflected by a reflector on the inner peripheral surface of the hood, mixed in one unit, and efficiently extracted to the outside of the hood.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a front view of a light emitting diode display device according to an embodiment of the present invention, and FIG. 2 is a right side view thereof.

1 and 2, the light-emitting diode display device has a front panel 2 as a display surface attached to a front surface of a housing 1 formed in a square frame shape when viewed from the front (horizontal). In the illustrated example, as shown in FIG. 2, a printed circuit board 1c on which a controller 1a, a connector 1b, and the like are mounted is connected to the back of the housing 1.

The front panel 2 has three R, G, B
A light-emitting display unit 2a having one pixel by combining various kinds of LED lamps 3, 4, and 5 is embedded in a uniform arrangement pattern. FIG. 3 shows the light emitting display unit 2a, L
It is an enlarged front view of the principal part which shows arrangement of ED lamps 3-5. LED lamps 3 to 5 are provided in the light emitting display unit 2a.
The respective centers are arranged so as to be located at the corners of the triangle, and form one pixel for full-color emission.

FIG. 4 shows a structure in which the light emitting display unit 2a is incorporated into the front panel 2. FIGS. 4 (a) and 4 (b) are views taken along lines AA and BB in FIG. 3, respectively. FIG.

The LED lamps 3 to 5 are, as in the prior art,
Lead frames 3a, 4 connected to printed circuit board 1c
a, 5a and these lead frames 3a, 4a, 5a
The resin heads 3b, 4b, which seal a light emitting element (not shown) mounted on the tip of the
5b. Heads 3b to 5b
Has a light-emitting portion as a whole, with a tapered tip, and its outer shape is a perfect circle as viewed from the front as shown in FIG. Such LED lamps 3 to 5 are provided with a waterproof resin 2 on the front panel 2 side of the light emitting display unit 2a.
c.

The light-emitting display unit 2a has an LE
A hood 2b that surrounds the heads 3b, 4b, 5b of the D lamps 3 to 5 from up, down, left, and right sides is formed to protrude from the front panel 2. This hood 2b is a front panel 2
To the front panel 2
The projecting length from is set to be equal to or greater than the opening width of the front opening of the light emitting display unit 2a so as to suppress the emission of sunlight or the like. Further, the hood 2b is formed of black polycarbonate, and together with the waterproof resin 2c described above, an LED is provided.
When no light is emitted from any of the lamps 3 to 5, the light emitting display unit 2a is made to appear black when viewed from the front.

A reflective material 2d is coated on the entire inner surface of the hood 2b except for the surface of the waterproof resin 2c inside the light emitting display unit 2a. The reflector 2d makes the inner peripheral surface of the hood 2b a pseudo mirror surface, improves the reflectance of the inner peripheral surface of the hood 2b, and reflects light emitted from the light emitting diode.

In the above configuration, the LED lamps 3 to 5
The emitted light is repeatedly reflected by the reflector 2d on the inner peripheral surface of the hood 2b, is mixed in one unit, and is extracted outside the front of the hood 2b. That is, since the light is extracted without being absorbed by the inner peripheral surface of the hood 2b, it is possible to efficiently collect the light from the LED lamps 3 to 5 without attenuating the light emission. as a result,
The contrast of each light emitting display unit 2a is improved, and a clear image can be obtained by the entire light emitting diode display device.

As described above, it is useful to coat the reflecting material 2d partially on the inner peripheral surface of the hood 2b as shown in FIG. 5 without coating the entire inner peripheral surface of the hood 2b. In FIG. 5, P is the vertical opening width of the hood 2b, L1 is the protruding length of the hood 2b, and L2 is the hood 2b.
b, coating length of the reflector 2d from the innermost part, L3
Indicates the length of the uncoated portion. For convenience of explanation, the LED lamps 3 to 5 constituting one pixel
Is disposed at the center of the hood 2b as an LED lamp 6. L1 has the same length as P, and L2 has L1.
70% of the length.

As shown in FIG. 5, the hood 2
By partially coating the inner peripheral surface of b with an uncoated portion having a length L3, the inserted sunlight is absorbed by the L3 portion where the black polycarbonate is exposed, and the reflection of the sunlight is prevented. The light emitting display unit 2
When a is looked up from below, the reflector 2d is not directly visible at a look-up angle greater than the angle indicated by φ in the figure, so that the reflector 2d does not appear brightly shining when the LED lamp 6 is not lit, and the contrast is reduced. I will not let you. The angle of φ can be changed by adjusting the length L2.

As described above, the hood 2b is
Although the D lamps 3 to 5 have been described as enclosing them from up, down, left, and right sides, a circular shape may be used so that the LED lamps 3 to 5 are inscribed. In this case, LED
Since the distance between the lamps 3 to 5 and the circular hood is reduced,
It is possible to further prevent the sunlight or the like from directly shining on the LED lamps 3 to 5, thereby reducing interference with an image.

Further, as shown in FIG. 6, the projecting length of the hood 2b is 50% of the opening width of the hood 2b.
The angle of the direct light emitted from the ED lamp 6 can be 45 °. Since the entire surface of the inner peripheral surface of the hood 2b is coated with the reflecting material 2d, LE
The light emitted from the D lamp 6 is reflected by the reflector 2d, and can emit light even at an angle of 45 ° or more. Thus, a light-emitting diode display device having a wide viewing angle can be provided.

[0029]

According to the present invention, the following effects can be obtained. (1) A hood surrounding the light emitting portion is formed so as to protrude from the display surface, and furthermore, a reflective material is provided on the inner peripheral surface of the hood, so that light emitted from the light emitting diode is reflected by the reflective material, and is provided outside the hood. Light can be extracted efficiently. Therefore, a clear image can be obtained by improving the contrast even with a light emitting element having a small amount of light. (2) By making the protruding length of the hood from the display surface 50% or more of the opening width of the hood, the direct light emitted from the light emitting diode can be radiated up to 45 °. A light-emitting diode display device with a wide viewing angle can be provided by radiating the light as reflected light from the inner surface reflecting material. (3) One pixel for full-color light emission composed of a combination of light-emitting diodes is defined as one unit, and the hood surrounds this one unit, so that light emitted from a plurality of light-emitting diodes constituting one pixel can be reflected in the hood. Since the light can be reflected by the reflective material on the peripheral surface and mixed in one unit and taken out, there is no interference of light emission between pixels, and the contrast can be further improved.

[Brief description of the drawings]

FIG. 1 is a front view of a light emitting diode display device according to an embodiment of the present invention.

FIG. 2 is a right side view of the light emitting diode display of FIG. 1;

FIG. 3 is an enlarged front view of a main part showing an arrangement of LED lamps constituting the light emitting display unit.

4 (a) is a sectional view taken along line AA of FIG. 3; FIG. 4 (b) is a sectional view taken along line BB of FIG. 3;

FIG. 5 is a longitudinal sectional view showing another embodiment of the light emitting display unit.

FIG. 6 is a longitudinal sectional view showing still another embodiment of the light emitting display unit.

FIG. 7 is a schematic view showing a main part of a conventional LED display, wherein (a) is a front view and (b) is a longitudinal sectional view.

[Explanation of symbols]

 1 Housing 1a Controller 1b Connector 1c Printed Circuit Board 2 Front Panel 2a Light Emitting Display Unit 2b Hood 2c Waterproof Resin 2d Reflector 3,4,5,6 LED Lamp 3a, 4a, 5a Lead Frame 3b, 4b, 5b Head

Claims (4)

[Claims] 1. A light-emitting display device in which light-emitting portions of light-emitting diodes are arranged on a display surface, wherein a hood surrounding the light-emitting portion is formed to protrude from the display surface, and a reflector is provided on an inner peripheral surface of the hood. A light-emitting display device, characterized in that: 2. A projecting length of the hood from a display surface,
The light-emitting display device according to claim 1, wherein the opening width of the hood is 50% or more. 3. The light-emitting display device according to claim 1, wherein one pixel for full-color light emission configured by combining the light-emitting diodes is one unit, and the hood surrounds the one unit. 4. A light-emitting display unit for full-color light emission comprising one pixel by combining three types of light-emitting diodes having red, green, and blue light-emitting colors, and a hood surrounding all light-emitting portions of the light-emitting diodes. A light emitting display unit comprising: a hood; and a reflective material on an inner peripheral surface of the hood.