JPH08287719A - Light emitting apparatus - Google Patents

Abstract

PURPOSE: To realize a matrix light emitting apparatus with high contrast. CONSTITUTION: LEDs 1 are arranged in a matrix in a substrate 2 coated with a reflection preventive resin 3 and covered with transparent resin 4 having dome-like projected parts. Respective projected parts are partitioned by light shielding walls 6 with the minimum height necessary to shield light-rays emitted mutually neighboring light sources. Consequently, even in the case where outside light-rays enter the light emitting apparatus, the light-rays are hardly reflected and the light-rays from neighboring light sources hardly enter the neighboring LEDs, so that the contrast between turned-on LEDs and turned-off LEDs can be heightened. Moreover, the light shielding walls 6 do not need to be made higher than the projected resin 4, so that visible angle can be widened. As for the projected parts 4, the more the distance of the tip parts and the LEDs 1 differs from the radius of the projected parts, the more light-rays are converged and on the other hand the more the distance becomes close to the radius, the more light-rays are dispersed. In this way, whether great importance is attached to high brightness or to wire visible angle becomes selective.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light emitting device in which light sources such as LEDs are arranged in a matrix.

[0002]

2. Description of the Related Art Conventionally, in a light emitting device in which light sources such as LEDs are arranged in a matrix, each light source part is constructed as shown in FIG.

In FIG. 5, a light emitting element 101 is a substrate 10.
It is implemented on 2. In order to effectively emit the light emitted from the light source 101, the molded product 103 has an inclined portion 105 opened toward the emission side for each light source, and the substrate 10
Stacked on top of two. Furthermore, a protection filter 104 for protecting the light source unit from stains is superposed on it. With this configuration, the light emitted from the light source 101 is reflected directly or by the inclined portion 105, and the protection filter 10
The light passes through 4 and is emitted to the outside.

[0004]

However, the light emitting device configured as shown in FIG. 5 has the following problems. That is, when a reflective material is used for the inclined part, the incident external light is reflected by the inclined part, so that the light source part is in the state of emitting light even when the light source is off, and the contrast between when the light source is on and when it is off Will be significantly reduced.

If a non-reflective material is used for the inclined portion in order to improve the contrast, only the direct light is emitted from the light source portion, the amount of emitted light is reduced and the visibility is deteriorated, and the direct light is blocked by the inclined portion. Since it is not possible to recognize whether the light is on or off from the position, the visible range is narrowed.

The present invention has been made in view of the above-mentioned conventional example, and an object thereof is to provide a high contrast light emitting device. Further, it is another object of the present invention to provide a light emitting device having high contrast and improved visibility.

[0007]

In order to achieve the above object, the light emitting device of the present invention has the following constitution. That is, a substrate that does not reflect light, a plurality of light sources arranged on the substrate, a convex portion that covers each of the plurality of light sources, and a lowest height that blocks light incident on the convex portion from an adjacent light source. By the way, a light shielding portion surrounding each of the convex portions is provided.

Further, the convex portion is made of a transparent material and is provided at a position where the light from the light source is condensed.

Alternatively, the convex portion is processed to diffuse light, and is provided at a position where the light from the light source is diffused.

[0010]

With the above structure, the light emitted from each of the plurality of light sources is blocked by the light shielding wall, and the external light is suppressed from being reflected by the substrate that does not reflect the light. Therefore, the amount of light emitted from the vicinity of the light source is reduced when the light source is off.

[0011]

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

FIG. 1 is a sectional view of a light emitting device in which LEDs are arranged in a matrix. In the figure, the LED 1 is mounted on a printed circuit board 2. The antireflection resin 3 is a black resin, a resin containing a matting material, or the like, and attenuates incident external light. The antireflection resin 3 is stuck on the substrate 2 so as to surround the LED and cover a portion other than the pattern used when mounting the LED. Thereby, reflection of external light can be prevented and contrast can be enhanced. The same effect as that of the antireflection resin 3 can be obtained by applying a black matte coating to the substrate 2 instead of the antireflection resin 3 or by using a material that does not reflect light as the material of the substrate 2.

The convex resins 4 and 5 are translucent resins formed in a dome shape so as to cover the LEDs, and if the distance from the top to the LEDs is shorter than the radius of the convex shape, L is used.
The light from the ED is diffused and, if long, the light is focused. The convex resins 4 and 5 are also provided for junction coating of the LED and protection from external stress.
As the material of this resin, a transparent resin, a resin containing a diffusing material, or the like is used depending on the application such as whether the light emitting device is a front high brightness type or a high viewing angle type.

The light-shielding wall 6 is made of black or matte resin and is provided so as to separate the respective LEDs. The light-shielding wall 6 blocks light from other LEDs and external light to enhance the contrast between lighting and extinguishing. The height b of the light shielding wall 6 is set to the minimum height that blocks the light a from the adjacent LED so that the light from the LED 1 can be efficiently emitted to the outside. Therefore, if the height b of the resin wall 6 is the same as the height of the convex resin 4 regardless of the shape of the convex resin 4, it is possible to block the light of the adjacent LED, so that the height is maximized and the front high brightness is obtained. It may be adjusted according to the spread of the emitted light depending on whether it is a type or a light viewing angle type. Each section separated by the resin wall 6 will be referred to as a light emitting section.

FIG. 4 is a plan view (FIG. 4A) and a sectional view (FIG. 4B) of a light emitting device having a 4 × 4 light emitting section. The light shielding wall 6 forms a concave portion that concentrically surrounds each light emitting portion. In such a structure, the light emitting device can display a desired pattern by illuminating the light emitting unit at a desired position.

As described above, the light emitting device of this embodiment can efficiently attenuate the light from the other light emitting portions and the external light incident on the light emitting portion, so that high contrast display can be performed. . Further, since the resin wall 6 that separates the light emitting unit from the light emitting unit is at the same height as the convex resin 4 at the highest, the viewing angle is widened and the visibility can be improved.

Further, by appropriately selecting the position of the convex resin and the material thereof, light is collected in a predetermined direction to increase the brightness, or the emitted light is diffused so that the viewing angle can be widened. You can also <Front High Brightness Type> FIG. 2 is a cross-sectional view of a light emitting portion in a front high brightness type light emitting device. The radius R of the curved surface of the convex resin 4 is shorter than the distance h between the top and the LED 1,
The outgoing light from D1 is focused forward (on the right side in the figure). In addition, a transparent resin is used as the material of the convex resin 4 to improve the light transmittance.

By configuring the light emitting unit in this way, the light emitting device has a high contrast, and since the light emitted from the LED is collected in front of the light emitting device, each light emitting unit emits light with high brightness. You can <Wide Viewing Angle Type> FIG. 3 is a sectional view of a light emitting portion in a wide viewing angle type light emitting device. The radius R of the curved surface of the convex resin 4 is longer than the distance h between the top and the LED 1,
The emitted light from is diffused. Light is further diffused by using a resin containing a diffusion material such as white fine particles or metal flakes as the material of the convex resin 4, or by forming the surface of the resin into a ground glass shape.

By configuring the light emitting portion in this way, the light emitting device has a high contrast, and the light emitted from the LED is diffused, so that the brightness is unlikely to change depending on the angle at which the device is viewed, and the light is shielded. Since the height of the wall is at most the height of the light emitting portion, the viewing angle can be widened.

[0020]

As described above, the light emitting device according to the present invention can realize high contrast light emission, and
There is an effect that the visibility can be enhanced by increasing the brightness or widening the viewing angle.

[0021]

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a light emitting device of an example.

FIG. 2 is a sectional view of a light emitting portion in a front high brightness type light emitting device.

FIG. 3 is a cross-sectional view of a light emitting portion in a high viewing angle type light emitting device.

FIG. 4 is a plan view (a) and a sectional view (b) of a light emitting device including a 4 × 4 light emitting unit.

FIG. 5 is a cross-sectional view of a conventional light emitting device.

[Explanation of symbols]

 1 LED, 2 substrate, 3 antireflection resin, 4 and 5 convex resin, and 6 light shielding wall.

Claims (3)

[Claims] 1. A substrate that does not reflect light, a plurality of light sources arranged on the substrate, a convex portion that covers each of the plurality of light sources, and a light source that blocks light incident on the convex portion from an adjacent light source. A light-emitting device comprising: a light-shielding portion that surrounds each of the convex portions at the lowest height. 2. The light emitting device according to claim 1, wherein the convex portion is made of a transparent material and is provided at a position where light from the light source is condensed. 3. The light emitting device according to claim 1, wherein the convex portion is processed to diffuse light and is provided at a position where the light from the light source is diffused.