JP2008211157A - Semiconductor light-emitting module, and apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain uniform planar light emission which is hardly affected by a reflectance of a mounting surface and in which quality of planar light emission is hardly reduced by a secular change and efficiency in taking out light is improved. <P>SOLUTION: A translucent case 203 is disposed to surround a direction irradiated with light of a semiconductor light-emitting element 111 and comprises eight or more reflection surfaces having different irradiation directions in a direction of an irradiated surface for the purpose of converging light radiated at 180° around a radiation axis of the semiconductor light-emitting element 111 onto a surface diffusion plate 501 and enabling approximately uniform planar light emission display. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a semiconductor light emitting module and device, and more particularly to a semiconductor light emitting module and device that improve light extraction efficiency and enable uniform surface light emission.

In recent years, semiconductor light emitting devices such as light emitting diodes (LEDs) with high energy efficiency in light emission have come to be used in various fields, and various devices using the semiconductor light emitting devices have been developed. In particular, the use of large currents has attracted attention for use as an alternative to conventional fluorescent lamps and incandescent lamps, and a technique has been proposed that enables uniform surface emission by improving the light extraction efficiency. Yes.
As an example, surface emission can be realized by arranging the irradiation axis of a bullet-type light emitting diode on the printed circuit board obliquely downward with respect to the irradiation surface and utilizing reflection on the substrate surface, or the printed circuit board. By placing a translucent resin case that has a light condensing characteristic obliquely downward with respect to the irradiation surface on the surface-mounted chip LED disposed above, and utilizing reflection on the substrate surface There is a technology for realizing surface emission.
In order to obtain uniform surface light emission, it can be easily realized by narrowing the pitch of the light emitting diodes. However, a large number of light emitting diodes are required, leading to an increase in cost and from the viewpoint of power consumption. It is judged that the technology cannot be adopted even if it is considered, and it is added that it was not taken up as a conventional technology for the present invention.

However, in the case of the above-described two examples, the structure that realizes surface light emission using light reflected on the substrate surface causes light loss due to light absorption on the substrate surface, and also to the irradiation surface. Since the distance of the light becomes longer, there is a problem that further light loss occurs.
Furthermore, although there are luminance variations and hue variations in individual light emitting diodes, there is a problem that it is difficult to reduce luminance variations and hue variations between adjacent light emitting diodes.
Furthermore, highly reflective white printing or the like is required on the substrate surface, leading to an increase in cost and a problem that the quality of surface light emission is degraded due to secular change of the reflecting surface.
Furthermore, it is necessary to use a lead wire or the like for power supply to the light emitting diode, but this lead wire or the like hinders reflection of light because it is necessary to use a part of the reflective surface on the substrate. Therefore, there is a problem that uniform surface light emission is difficult to obtain.

The present invention has been made in view of such a problem, and an object of the present invention is to provide a semiconductor light-emitting module and device that improve the light extraction efficiency and enable uniform surface light emission.
It is another object of the present invention to provide a semiconductor light emitting module and device that are not easily affected by the reflectance of the mounting surface and are less susceptible to quality deterioration as surface light emission due to secular change.

  In order to achieve such an object, a semiconductor light emitting module according to claim 1 includes a semiconductor light emitting element, a substrate body including a distribution film electrically connected to each semiconductor light emitting element, and a semiconductor light emitting device. One or a plurality of translucent cases arranged in the light irradiation direction of the element are provided, and the translucent case includes eight or more reflecting surfaces having different irradiation directions in the irradiation surface direction. And

  According to a second aspect of the present invention, in the semiconductor light emitting module according to the first aspect, the translucent case has a surface that reflects a part of the light emitted from the adjacent semiconductor light emitting element in the irradiation surface direction. It is characterized by having.

As described above, according to the present invention, a semiconductor light emitting module includes a semiconductor light emitting element, a substrate body including a distribution film electrically connected to each of the semiconductor light emitting elements, and the light of the semiconductor light emitting element. Since one or more translucent cases are arranged in the direction of irradiation, and the translucent case has eight or more reflecting surfaces having different irradiation directions in the direction of the irradiation surface, the light extraction efficiency Thus, it is possible to provide a semiconductor light emitting module and device capable of improving surface quality and enabling uniform surface light emission.
According to the present invention, in the semiconductor light emitting module, the translucent case is provided with a surface that reflects part of the light emitted from the adjacent semiconductor light emitting element in the direction of the irradiation surface, so that the light extraction efficiency is improved. It is possible to provide a semiconductor light-emitting module and device that can be improved to enable uniform surface light emission.

(Embodiment)
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

(Structure of semiconductor light emitting module)
FIG. 1 is a partial front view and cross-sectional view showing the structure of a semiconductor light emitting module according to an embodiment of the present invention, and FIG. 2 is a front view showing the whole when incorporated in a semiconductor light emitting device. It is a figure and sectional drawing.
The semiconductor light emitting module 101 of the present embodiment is disposed in a direction in which the semiconductor light emitting element 111 is irradiated with light, and a substrate body 105 including a power distribution film 104 electrically connected to each of the semiconductor light emitting elements 111. A translucent case 203 is formed. One or more semiconductor light emitting elements 111 that emit light when actually energized are connected to the power distribution film 104 via conductive wires 112. The power distribution film 104 has a positive electrode and a negative electrode.

  The substrate body 105 including the power distribution film 104 may employ any method known in this technical field as long as it is formed so as to provide electrodes to the semiconductor light emitting element 111. A printed board may be used, or a metal board and a printed board with improved heat dissipation can be used. In addition, it is preferable to perform resist printing in the place which needs the wiring etc. on the power distribution film 104, and it is more preferable that the color is white.

The semiconductor light emitting element 111 and the power distribution film 104 are electrically connected by a conductive wire 112, and power is supplied from a power source via a terminal provided in any part of the power distribution film 104. Note that the conductive wire 112 is not necessarily required when the semiconductor light emitting element 111 is a flip chip type or the like.
In addition, any terminal shape and structure known in this technical field may be adopted, and a lead wire or the like may be soldered. Moreover, you may attach to the power distribution film 104 as another part. In addition, it is preferable to perform the surface plating known in this technical field in the location where the conductive wire 112 of the power distribution film 104 is connected. In some cases, it is preferable to seal the semiconductor light emitting element 111, the conductive wire 112, or the surface plating portion with a resin or the like for protection.
Further, in this embodiment, the structure in which the semiconductor light emitting element 111 is directly bonded has been described. However, for example, substantially the same effect can be obtained even when a surface mount type chip LED is used.

It is also possible to increase the amount of light by mounting a plurality of semiconductor light emitting elements 111 of the same color in one bonding area, and for example, full color display is possible by mounting the semiconductor light emitting elements 111 of red, green and blue. It becomes.
Further, by combining the semiconductor light emitting element 111 and the phosphor, for example, white light can be obtained.

  The light emitted from the semiconductor light emitting element 111 is irradiated in the direction of 180 degrees with a slight difference in intensity around the irradiation axis of the semiconductor light emitting element 111. Further, the distance relationship between the semiconductor light emitting element 111 and the surface diffusion plate 501 is closest to the semiconductor light emitting element 111, and the distance increases as the distance from the center of the semiconductor light emitting element 111 increases. Therefore, when the irradiation light of the semiconductor light emitting element 111 is viewed from directly above the surface diffusion plate 501, the center of the semiconductor light emitting element 111 is the brightest and becomes darker gradually as the distance increases concentrically. This phenomenon is largely caused by total reflection of light on the inner surface side of the surface diffusion plate 501. This is because incident light wider than about 45 degrees out of light irradiated on the inner surface side of the surface diffusion plate 501 increases the ratio of total reflection. Therefore, for example, in the surface emitting display in which the distance between the semiconductor light emitting element 111 and the surface diffusion plate 501 is 20 mm and the pitch between the semiconductor light emitting element 111 and the semiconductor light emitting element 111 is 30 mm in both the vertical and horizontal directions, This results in a surface emitting display with a large unevenness in light emission luminance.

The light emitted from the semiconductor light emitting element 111 is attenuated as the distance to the surface diffusion plate 501 increases.
Therefore, in order to improve the light extraction efficiency and obtain uniform surface light emission, the pitch between the semiconductor light emitting element 111 and the semiconductor light emitting element 111 can be set under the condition that the distance between the semiconductor light emitting element 111 and the surface diffusion plate 501 is short. Ideally, the amount of light between the semiconductor light emitting element 111 and the semiconductor light emitting element 111 is made equal as much as possible.

In order to satisfy this condition, the translucent case 203 is disposed so as to surround the light irradiation direction of the semiconductor light emitting element 111, and is 180 degrees around the irradiation axis of the semiconductor light emitting element 111. For the purpose of condensing the irradiated light on the surface diffusing plate 501 and enabling substantially uniform surface emitting display, there are provided eight or more reflecting surfaces having different irradiation directions in the irradiation surface direction.
As a result of the experiment, it was found that when the number of reflection surfaces having different irradiation directions in the irradiation surface direction is eight or less, uniform surface emission cannot be obtained when it is assumed that the viewing angle of the surface diffusion plate 501 is different. did. Therefore, the light emitted from the semiconductor light emitting element 111 is provided with a translucent case 203 having a cross-sectional shape shown in FIG. A surface emission display could be obtained. This is possible because it has a light collecting function with a plurality of irradiation directions.
If there are eight or more reflecting surfaces with different irradiation directions in the irradiation surface direction, a substantially uniform surface emitting display can be obtained. However, the more reflecting surfaces, the more uniform surface emitting display can be obtained.

  Since the translucent case 203 has a light collecting characteristic in the direction of the irradiated surface and obtains a substantially uniform surface emitting display, a highly reflective white print or the like is provided on the surface opposite to the irradiated surface. Do not need. Therefore, for example, quality deterioration as a surface light emitting display due to secular change of the printed circuit board surface hardly occurs. In addition, it is necessary to use the lead wire 115 or the like for power supply to the semiconductor light emitting device 111. However, even when the lead wire 115 or the like is arranged using a part of the reflection surface on the substrate, the lead wire 115 or the like inhibits light reflection. Therefore, it is possible to obtain substantially uniform surface light emission.

  Further, the semiconductor light emitting element 111 has individual luminance variations and hue variations. In order to solve this problem, the translucent case 203 is provided with a surface that reflects part of the light emitted from the adjacent semiconductor light emitting element 111 in the direction of the irradiation surface. As a result, it becomes possible to take in the light of the adjacent semiconductor light emitting element 111 and irradiate the surface diffusion plate 501 with the light of its own semiconductor light emitting element 111. Therefore, individual luminance variations and hue variations existing in the semiconductor light emitting device 111 can be reduced, and a substantially uniform surface emitting display can be obtained. In FIG. 3, the locus of this light is indicated by a broken line.

  The translucent case 203 is preferably formed of a highly transparent resin such as acrylic or polycarbonate, but glass or other resins can also be used. The shape is preferably set individually depending on the distance between the semiconductor light emitting element 111 and the surface diffusion plate 501, the pitch between the semiconductor light emitting element 111 and the semiconductor light emitting element 111, and the required characteristics. Further, the surface state of the translucent case 203 has options such as a mirror surface and a matte surface, and it is preferable to use them properly depending on required characteristics.

  The translucent case 203 may be fixed to the substrate body 105 provided with the power distribution film 104 using, for example, an adhesive, or a boss is formed on the translucent case 203 and the substrate body provided with the power distribution film 104. Fixing may be performed by heat caulking by providing holes at appropriate positions 105, and any fixing method known in the art may be employed.

  The basic structure of the semiconductor light emitting module 101 of this embodiment has been described above with reference to FIGS. 1 to 3. For example, the translucent case 203 can be made of a material such as acrylic polycarbonate or glass. However, not only this but any member known in this technical field can be used, and it can be set as arbitrary shapes. In addition, when the characteristics can be maintained, a plurality of translucent cases 203 can be connected. Further, instead of the surface diffusion plate 501, for example, a transparent surface plate having a diamond cut surface can be used. In addition, although the limiting resistor of the semiconductor light emitting element 111 may be attached to the power distribution film 104, it is added that it is omitted in this description.

  Moreover, it goes without saying that these semiconductor light emitting modules can be used as various light emitting materials such as signals as well as light sources and illuminations for surface light emitting displays.

(Effect of the semiconductor light emitting module of the present invention)
As described above, the semiconductor light emitting module of the present invention is not easily affected by the reflectance of the mounting surface, hardly deteriorates the quality of surface light emission due to aging, and achieves uniform surface light emission by improving the light extraction efficiency. can do.

It is a front view which shows the structure of the semiconductor light-emitting module concerning one Embodiment of this invention, (a) is the front view which expanded the part, (b) is the side view. BRIEF DESCRIPTION OF THE DRAWINGS It is drawing which shows the structure of the semiconductor light-emitting device concerning one Embodiment of this invention, (a) is a front view of the state which removed the surface diffusion plate, (b) of the state which attached the surface diffusion plate It is a side view. It is a figure for demonstrating the effect of this invention, and is the side view which showed the locus | trajectory of the light of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 101 Semiconductor light emitting module 104 Power distribution film 105 Substrate body 111 Semiconductor light emitting element 112 Conductive wire 115 Lead electric wire 203 Translucent case 501 Surface diffusion plate 502 Housing

Claims (2)

  A semiconductor light-emitting element, a substrate body provided with a power distribution film electrically connected to each of the semiconductor light-emitting elements, and a translucent case disposed in the light irradiation direction of the semiconductor light-emitting element Alternatively, a semiconductor light emitting module comprising a plurality of reflective surfaces having a plurality of reflecting surfaces having different irradiation directions in the irradiation surface direction.   2. The semiconductor light emitting module according to claim 1, wherein the translucent case includes a surface that reflects a part of light emitted from the semiconductor light emitting element adjacent thereto in an irradiation surface direction.

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