Optical semiconductor device

Description: TECHNICAL FIELD [Detailed description of the invention]

【0001】

[Industrial application field]

The present invention relates to an optical semiconductor device formed by arranging a plurality of light-emitting molecules at predetermined intervals, and displays predetermined information by a combination of turning on and off the light-emitting devices. In particular, the present invention relates to an optical semiconductor device capable of clearly displaying information regardless of changes in the amount of incident light of external light or the position of a viewer.

【0002】

[Conventional technology]

An optical semiconductor device as a display unit formed by arranging a plurality of light emitting elements in a matrix in an enclosure can display predetermined information by turning on or off the light emitting elements.

【0003】

At present, this optical semiconductor device is widely used indoors or outdoors as a display device such as a display panel by combining a predetermined number of them.

【0004】

For example, these display devices are installed on the shoulders of highways to provide drivers with highway road information, or in station premises to provide users with information on train departure and arrival times. It has been installed.

【0005】

FIG. 2A is a plan view of the optical semiconductor device 1 as a display unit of the conventional display device. The display unit 1 is composed of nine light emitting elements 2. The light-emitting diodes (LEDs) 2 are regularly arranged in a matrix in the enclosure 3. The space between the light emitting elements 2 in the outer enclosure 3 is filled with a resin 4 for fixing the light emitting element 2 in the outer enclosure 3.

【0006】

FIG. 2B is a cross-sectional view taken along the line AA'of the optical semiconductor device 1 shown in FIG. 2A. By combining a plurality of the optical semiconductor devices 1 and arranging them on a plane, for example, a display device for displaying train information in the station yard described above can be formed.

【0007】

FIG. 3A is a plan view of a display device 7 made by combining a plurality of conventional optical semiconductor devices 1. FIG. 3B is a cross-sectional view of the display device 7 shown in FIG. 3A along the BB'line.

【0008】

When the display device 7 shown in FIG. 3A is installed outdoors, for example, the sun's rays are directly incident on the light emitting element 2, that is, the LED lamp. In this case, it becomes difficult to distinguish whether the LED lamp 2 is on or off, and as a result, there is a problem that the display information cannot be recognized.

【0009】

In order to solve this problem, conventionally, for example, as shown in FIG. 2B, a louver 5 is provided in a part of the enclosure 3 in the optical semiconductor device 1 and the external light is directly incident on the LED lamp 2. I was trying not to.

【0010】

As a result, when the LED lamp 2 is turned off, external light is less likely to be incident on the LED lamp 2 and the resin 4, and the difference between the amount of light when the light emitting element 2 is turned on and the amount of reflected light when the LED lamp 2 is turned off becomes large. That is, the contrast of brightness of the entire optical semiconductor device increases. Therefore, good display is possible.

【0011】

However, when the display device 7 is configured, the optical semiconductor devices 1 are arranged in a matrix. If the length of the louver 5 provided in the outer enclosure 5 is increased in order to suppress the influence of external light, the visibility in the vertical direction, especially in the display device, is impaired. Therefore, it may be necessary to shorten the length of the louver 5 depending on the installation location of the display device, the size of the display portion, and the like. For example, in the case of a display device made by using the optical semiconductor device shown in FIGS. 2A and 2B, the LED lamp 2 may be difficult to see when viewed from the B direction. Therefore, it becomes necessary to shorten the length of the louver 5.

【0012】

In such a case, the louver 5 could not sufficiently block the outside light, and the contrast with respect to the specific direction when the LED lamp 2 was turned on and off was deteriorated.

【0013】

Further, as the resin 4 for fixing the light emitting element 2 to the enclosure, a resin 4 having a low viscosity is generally used. That is, when a highly viscous resin is used, it is for avoiding the formation of cavities around the light emitting element 2 when the resin is poured around the light emitting element 2 and solidified. However, when the resin 4 having a low viscosity is used, its surface becomes a mirror surface. As a result, when the external light is incident on the surface of the resin 4, it is reflected in a specific direction, so that there is a problem that the display information cannot be recognized.

【0014】

As a countermeasure against such a problem, in the reflection of the external light in the LED lamp 2, it is possible to suppress the reflected light to some extent by changing the shape of the LED lamp 2. However, no effective measures have been taken for the resin 4 to be filled.

【0015】

[Problems to be Solved by the Invention]

As described above, in the conventional optical semiconductor device 1 mainly used for an outdoor display device, the length of the light-shielding louver 5 provided in the outer enclosure 3 cannot be increased, and therefore the length cannot be increased. There is a drawback that the reflection of external light on the surface of the resin 4 filled in the outer enclosure is strengthened, and the optical semiconductor device, that is, the display device is difficult to see.

【0016】

Therefore, the present invention has been made to solve the problems of the above-mentioned conventional optical semiconductor device.

【0017】

An object of the present invention is to have a structure in which external light incident from the outside is not reflected in a specific direction, and to improve the contrast which is the difference between the brightness when the display device is lit and the brightness when the display device is turned off. Another object of the present invention is to provide an optical semiconductor device having a display function capable of accurately and clearly recognizing display information by a viewer.

【0018】

[Means for solving problems]

In order to achieve the above object, as a preferred embodiment of the optical semiconductor device of the present invention, a substrate, a plurality of light emitting elements arranged in a predetermined arrangement on the substrate, the substrate and the light emitting element are housed. A first layer, which is filled on the substrate and between the enclosure and the light emitting element, and for fixing the light emitting element between the substrate and the surrounding device, and the above. It is composed of a second layer formed on the first layer, and the second layer is formed in the shape of fine irregularities so as to diffusely reflect the incident external light on the exposed surface. It is an optical semiconductor device characterized by.

【0019】

In particular, the second layer is characterized in that it is formed of a black member so as to be able to further absorb incoming external light.

【0020】

Further, the first layer is formed of a member having a high reflectance capable of reflecting the light emitted by the light emitting element, and the second layer can further absorb the incident external light. It is characterized by being formed of a black member.

【0021】

Further, the boundary line between the first layer and the second layer is formed at a position higher than the position of the light emitting portion in the light emitting element when viewed from the position of the substrate.

【0022】

As another preferred embodiment of the optical semiconductor device of the present invention, a substrate, a plurality of light emitting elements arranged in a predetermined arrangement on the substrate, an enclosure for accommodating the substrate and the light emitting elements, and the like. It is filled on the substrate and between the enclosure and the light emitting element, and is composed of a layer for fixing the light emitting element between the substrate and the enclosure, and the exposed surface of the layer is formed. It is an optical semiconductor device characterized in that it is formed in an uneven shape so as to diffusely reflect incident external light.

【0023】

Further, the layer is characterized in that it is formed of a black member so as to be able to further absorb incident external light.

【0024】

Furthermore, the layer is characterized in that it is formed of a member having a high reflectance capable of reflecting the light emitted by the light emitting element.

【0025】

[Action]

In the configuration of the optical semiconductor device of the present invention described above, the second layer laminated on the first layer filled in the enclosure reflects the external light incident on the surface of the second layer in a specific direction. Diffuse reflection or absorption without being done.

【0026】

[Example]

Hereinafter, examples of the optical semiconductor device of the present invention will be described with reference to the drawings.

【0027】

FIG. 1 is a cross-sectional view of an optical semiconductor device according to a first embodiment of the present invention.

【0028】

In FIG. 1, in the optical semiconductor device 10, a plurality of light emitting elements connected on a printed substrate 11, for example, LED lamps 12 are arranged in a matrix in an enclosure 13 and are housed around a part of the LED lamps 12. It is filled with one layer of resin 14. Further, the light scattering member 15 of the second layer, which is a feature of the first embodiment, is formed by being joined onto the resin 14 of the first layer. That is, a part of the periphery of the LED lamp 12 excluding the illuminated portion of the LED lamp 12 is formed by a two-layer laminated structure of the resin 14 of the first layer and the light scattering member 15 of the second layer.

【0029】

Next, the method of forming the optical semiconductor device of this embodiment will be described with reference to FIGS. 4A, 4B, and 4C.

【0030】

4A is a plan view of the optical semiconductor device in FIG. 1, FIG. 4B is a cross-sectional view of the light scattering member 15 of the second layer shown in FIG. 1, and FIG. 4C is a resin layer 14 of the first layer shown in FIG. It is a plan view. Holes 16H for inserting the protrusions 16 of the light scattering member 15 which is the second layer are provided at the four corners of the resin layer 14 as the first layer.

【0031】

As shown in FIG. 4B, the light scattering member 15 as the second layer of this laminated structure is processed so that the surface 15A opposite to the surface bonded to the resin 14, that is, the surface in contact with the atmosphere becomes fine irregularities. Is formed. Various methods can be mentioned as the processing method. For example, a method in which fine particles are attached to one surface of a mold and a resin as a softened light scattering member 15 is injected into the mold is used to form the mold. is there.

【0032】

The light scattering member 15 thus formed is provided on the back surface of the light scattering member 15 before the resin 14 of the first layer is filled between the light emitting elements 12 in the enclosure 13 and cured. The protruding portion 16 is pressed and inserted into the resin 14 to be temporarily fixed, and then fixed to the resin 14 by curing the resin 14, and is placed and fixed in the enclosure 13.

【0033】

As described above, since the exposed surface 15A of the light scattering member 15 is processed so as to be uneven, the external light incident on the surface of the light scattering member 15 is diffusely reflected and is not reflected in a specific direction. .. Further, by making the light scattering member 15 of the second layer black, it is possible to reduce the amount of reflected light on the surface 15A of the second layer because it absorbs external light. As a result, even if external light is incident on the optical semiconductor device when the LED lamp 12 is turned off, the reflected light of the optical semiconductor device as a whole becomes small, and the amount of light when the LED lamp 12 is turned on and the amount of reflected light of the external light when the LED lamp 12 is turned off. The difference in the amount of light of the entire device will be improved. Therefore, in a display device formed by arranging such optical semiconductor devices 10 in a matrix, clear display can be performed without being difficult to see as in a conventional display device.

【0034】

In the first embodiment, the light scattering member 15 is made of resin, but the present invention is not limited to this, and may be, for example, metal. Further, the filling member 14 of the first layer and the filling member 15 of the second layer may be joined by, for example, an adhesive without providing the protruding portion 16 on the back surface of the filling member 15 of the second layer.

【0035】

FIG. 5 is a diagram showing a cross-sectional structure of the optical semiconductor device 20 according to the second embodiment of the present invention. In addition, in FIG. 5 and FIGS. 6 and 7 shown below, the components having the same reference numerals as those in FIG. 1 are the same components, and the description thereof will be omitted.

【0036】

The feature of the embodiment shown in FIG. 5 is that the resin 17 is filled around a part of the LED lamp 12 excluding the irradiated portion, and the exposed surface 17A of the filled resin 17 is processed so as to be uneven. It is in. As a method of directly satin-finishing the surface 17A of a filling member such as resin 17, for example, when the filled resin 17 is in a softened state, a tape-shaped cloth is pressed against the surface 17A of the resin 17 to cover it. There is a method in which the mesh pattern of the cloth is transferred to the resin surface 17A by removing the cloth after the resin 17 is softened, and the surface is processed and formed into fine irregularities.

【0037】

The optical semiconductor device 20 obtained by the above method can obtain the same effect as the optical semiconductor device 10 of the first embodiment described above.

【0038】

FIG. 6 is a diagram showing a cross-sectional structure of the optical semiconductor device 30 according to the third embodiment of the present invention.

【0039】

The feature of the optical semiconductor device 30 of the third embodiment shown in FIG. 6 is that the optical semiconductor device 20 of the second embodiment described above is formed as a second layer on the surface 18A of the resin 18 to be filled. By spraying the finely granular black resin layer 19 immediately after filling the resin 18, the surface of the black resin layer 19 on the surface of the resin 18 is processed and formed into an uneven shape. Even in such an embodiment, it is possible to obtain the same effect as the optical semiconductor devices 10 and 20 of the above-described embodiment, and the same effect can be obtained even if the granules are removed after spraying.

【0040】

FIG. 7 is a diagram showing a cross-sectional structure of the optical semiconductor device 40 according to the fourth embodiment of the present invention.

【0041】

The feature of the optical semiconductor device 40 of the embodiment shown in FIG. 7 is that the filling member 22 as the second layer is formed of a highly viscous resin with respect to the optical semiconductor device 10 of the first embodiment. The exposed surface 22A was processed into an uneven shape. As the method for processing the unevenness, the above-mentioned method can be applied, and as another method, for example, a resin mixed with fine-grained glass, silica, or the like may be applied to the surface. Also. The second layer may be formed of a glass fibrous metal. In addition, this method may be applied to the said Example.

【0042】

Even in the optical semiconductor device of this embodiment, the same effect as that of the optical semiconductor devices 10, 20, 30 of the above-described embodiment can be obtained.

【0043】

FIG. 8 is a cross-sectional view of the optical semiconductor device 50 according to the fifth embodiment of the present invention. In the figure, the light reflectance may be increased by using, for example, a white resin for the filling member 24 in the stratified region as the first layer. In such a case, the light emitted from the side and bottom of the light emitting element can be taken out to the front surface 12F of the light emitting element, the brightness of the light emitting element becomes stronger, and the displayed information can be easily recognized as a result. can do. In the case of this embodiment, as shown in FIG. 8, the position L1 of the pellet 29 needs to be set to be smaller than the height L2 of the boundary between the first layer and the second layer.

【0044】

In the optical semiconductor device 10 of the first embodiment of the present invention, the shapes of the protrusions 16 and the holes 16H for firmly joining the first resin layer 14 and the second layer 15 were columnar. ..

【0045】

However, the present invention is not limited to this shape, and in order to further strengthen the bonding strength between the first layer and the second layer, for example, as shown in FIG. 9, the second layer 28 The cross-sectional shape of the protrusion 26 of the above may be formed so as to be triangular toward the first resin layer.

【0046】

When the first resin layer 27 of this embodiment is completely solidified, the second layer 28 and the first resin layer 27 are the first resin layer 14 and the first resin layer 14 of the optical semiconductor device of the first embodiment described above. It is even stronger than the bond strength of layer 15 of 2 and is less likely to peel off from each other. Further, when a display device in which the devices of the present invention are arranged in a matrix is configured, a louver may be provided on the enclosure 13 to the extent that the displayed information is not impaired by the viewing angle.

【0047】

As described above, according to the present invention, since the exposed surface of the filling member filled in the enclosure accommodating the light emitting element is formed by a layer capable of scattering or absorbing incident light, it is incident on the exposed surface of the filling member. It is possible to suppress the reflection of external light in a specific direction. This makes it possible to easily recognize the display information of the device as a whole when the light emitting element is turned on and off, and to provide an optical semiconductor device capable of achieving a clear display.

【0048】

[Effect of the invention]

As described above, according to the optical semiconductor device of the present invention, the exposed surface of the filling member filled in the outer enclosure for accommodating the light emitting element is formed so as to efficiently scatter or absorb the incident light. , It is possible to suppress the reflection of external light incident on the exposed surface of the filling member in a specific direction. As a result, it is possible to provide an optical semiconductor device capable of achieving good display without impairing visibility by enhancing the contrast of the brightness of the device as a whole when the light emitting element is turned on and off.

[Simple explanation of drawings]

[Figure 1]

It is sectional drawing of the optical semiconductor device which is 1st Example of this invention.

[Figure 2]

It is a block diagram of the conventional optical semiconductor device.

[Fig. 3]

It is a block diagram of the conventional display device formed by arranging a plurality of optical semiconductor devices shown in FIG.

[Fig. 4]

It is a block diagram of the optical semiconductor device shown in FIG.

[Fig. 5]

It is sectional drawing of the optical semiconductor device which is 2nd Example of this invention.

[Fig. 6]

It is sectional drawing of the optical semiconductor device which is 3rd Example of this invention.

[Fig. 7]

It is sectional drawing of the optical semiconductor device which is 4th Example of this invention.

[Fig. 8]

It is sectional drawing of the optical semiconductor device which is 5th Example of this invention.

[Fig. 9]

This is a modification of the protrusion of the optical semiconductor device according to the first embodiment of the present invention.

[Explanation of symbols]

10 Optical semiconductor device 11 Printed circuit board 12 LED lamp 13 Enclosure 14 First layer resin 15 Light scattering member of the second layer 16 holes (protrusions)