JP2006165096A - Envelope for light-emitting element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enable controlling a radiation angle without adding a complicated manufacturing process for an envelope for a light-emitting element. <P>SOLUTION: A convex portion 23 having a height higher than the depth of a concave portion 21 and provided with a reflection surface on its sidewall is provided at the center of the concave portion 21 in a package 20, and a transparent material 30 having viscosity is implanted to the concave portion 21 from the convex portion 23 so that the light-emitting element 1 and the convex portion 23 may be covered. In this way, since the transparent material 30 is formed into a rising lens shape, the radiation angle can be changed. The angel or height of the reflection surface of the convex portion 23 is adjusted, thereby changing the shape of the lens made of the transparent material 30, and the radiation angle can be easily controlled. Also, the transparent material 30 is implanted while it adheres to the convex portion 23 due to its viscosity in the manufacturing process and reserved inside the concave portion 21 while forming the lens shape, and thus, only one-time implantation of the transparent material 30 into the concave portion 21 can be enough. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an envelope of a light emitting element that emits light emitted by the light emitting element to the outside.

  A light emitting element such as a light emitting diode (LED) needs an envelope (package) in order to efficiently emit light to the outside. One example is a large SMD (Surface Mount Device) envelope.

  As such an envelope, for example, the one described in Patent Document 1 is known. As shown in the perspective view of FIG. 8 and the cross-sectional view of FIG. 9, the conventional envelope includes a recess 21 whose inner wall is inclined in the package 20, and a metal cathode-side lead frame 11 on the bottom surface of the recess 21. The anode side lead frame 12 is disposed separately.

  The lower electrode of the light emitting element 1 is connected to the lead frame 11 with a conductive material such as silver paste, and the upper electrode of the light emitting element 1 is connected to the lead frame 12 through the wire 3. The concave portion 21 includes a reflection surface that reflects light from the light emitting element 1 in a state close to complete diffuse reflection on the inner wall, and the package 20 is formed of white polyphthalamide resin so that such reflection is possible. The

  The transparent material 30 is injected into the recess 21 in a liquid state from the opening on the upper surface, and then heated and cured. As the transparent material 30, for example, a translucent epoxy resin is used. The surface of the transparent material is almost flat because gravity is applied evenly.

  With such a configuration, the envelope shown in the figure radiates the direct light emitted from the light emitting element 1 and the reflected light reflected by the reflecting surface of the recess 21 to the outside through the transparent material 30. FIG. 10 is a diagram showing a radiation pattern in the envelope having the above configuration. As shown in the figure, the radiation angle (full angle at half maximum) θ is relatively wide at 110 °.

Further, in order to realize color mixing including white, a plurality of light emitting elements of different colors may be mounted on the envelope as shown in the perspective view of FIG. In the figure, the electrodes at the lower ends of the light emitting elements 1a, 1b, and 1c of RBG three colors are connected to the separate lead frames 11a, 11b, and 11c on the cathode side by silver paste or eutectic solder. The upper electrodes of the light emitting elements 1a, 1b, and 1c are connected to the common anode-side lead frame 12 through the corresponding wires 3a, 3b, and 3c. Also in this case, the surface of the transparent material 30 injected into the recess 21 is substantially flat.
JP 2003-163378 A

  However, the envelopes having the above-described configurations have a problem that the radiation angle cannot be controlled when it is necessary to widen or narrow the radiation angle. Moreover, when manufacturing an envelope in which the radiation angle can be controlled, it is desirable that the envelope can be manufactured at a low cost without adding a complicated manufacturing process.

  This invention is made | formed in view of the above, The place made into the subject is enabling it to control a radiation angle, without adding a complicated manufacturing process about the envelope of a light emitting element.

  The envelope of the light-emitting element according to the present invention includes a concave portion having a reflective surface on the inner wall, a convex portion disposed at the center of the concave portion and having a reflective surface on the side wall that is higher than the depth of the concave portion, and the concave portion. It has a light emitting element arranged around the convex part, a light emitting element in the concave part, and a transparent material having viscosity injected from the convex part so as to cover the convex part.

  In the present invention, a convex portion that is higher than the depth of the concave portion and provided with a reflective surface on the side wall is disposed at the center of the concave portion, and the light emitting element is disposed in the concave portion. By injecting the material, the transparent material is formed into a raised lens shape, so that the radiation angle can be changed. Then, by adjusting the angle and height of the reflection surface of the convex portion, the shape of the lens made of the transparent material changes, so that the radiation angle can be easily controlled. In addition, since the transparent material is injected while adhering to the convex portion with viscosity in the manufacturing process and stays in the concave portion while forming the lens shape, the step of injecting the transparent material into the concave portion can be performed only once. .

  According to the envelope of the light emitting element of the present invention, the emission angle can be controlled without adding a complicated manufacturing process.

  FIG. 1 is a perspective view showing a configuration of an envelope of a light emitting element in an embodiment, and FIG. 2 is a cross-sectional view thereof. This envelope includes a recess 20 whose inner wall is a reflective surface in a package 20 having a frame structure. The package 20 is formed of white PPA (polyphthalamide) resin so that the light received by the reflecting surface of the recess 21 is reflected in a state close to perfect diffuse reflection. In the center of the concave portion 21, a convex portion 23 that is higher than the depth of the concave portion 21 and has a reflecting surface on the side wall is disposed. The convex part 23 has a truncated cone shape whose upper part is cut flat. The convex portion 23 is formed on the bottom surface of the concave portion 21 in one step by injection molding using a mold.

  On the bottom surface of the recess 21, metal cathode-side lead frames 11a, 11b, 11c... And anode-side lead frames 12a, 12b, 12c. These lead frames 11a, 11b, and 11c have light emitting elements 1a, 1b, 1c (hereinafter collectively referred to as “light emitting element 1”) made of corresponding LEDs (Light Emitting Diodes) or the like with silver paste or a common electrode. Each is connected by crystal solder. The light emitting elements 1 may all be the same color, or may be different colors in order to achieve a mixed color including white. The electrode at the upper end of each light emitting element 1 is connected to the corresponding lead frames 12a, 12b, 12c via the corresponding wires 3a, 3b, 3c.

  A transparent material 30 having viscosity is injected from the convex portion 23 into the concave portion 21 so as to cover the light emitting element 1 and the convex portion 23. For example, an epoxy resin is used as the transparent material 30. When injecting the transparent material 30, the transparent material 30 is injected from the upper part of the convex part 23, and is made to adhere to the convex part 23 with its viscosity. In this embodiment, since the upper part of the convex part 23 is a flat surface, the transparent material 30 is received by this flat surface so that the transparent material 30 gradually flows from the convex part 23 to the concave part 21 due to viscosity. Thus, the transparent material 30 can be formed into a raised lens shape. At this time, the injection amount of the transparent material is set appropriately so that the transparent material 30 does not spill out of the recess 21. Then, while the lens shape is maintained by the viscosity of the transparent material 30, the transparent material 30 is cured by heating or ultraviolet irradiation.

  By passing through such a process, the lens shape which finally rose about the transparent material 30 is obtained. The light emitted from each light emitting element 1 is diffusely reflected by the reflection surface of the inner wall of the concave portion 21 and the reflection surface of the side wall of the convex portion 23.

  FIG. 3 is a diagram showing a radiation pattern by the envelope. Due to the lens effect of the convex portion of the transparent material 30, a narrow radiation angle is obtained compared to the conventional one of FIG. However, since a part of the light diffusely reflected by the convex portion 23 is also emitted from the side portion of the transparent material 30, the emission angle pattern in FIG.

  In this envelope, the radiation angle can be easily controlled by adjusting the angle and height of the reflecting surface of the convex portion 23. For example, when the radiation angle is made narrower, as shown in the cross-sectional view of FIG. 4, the height of the convex portion 23 is increased, or the angle of the reflective surface of the convex portion 23 with respect to the bottom surface of the concave portion 21 is made steep. . On the contrary, when the radiation angle is widened, the height of the convex portion 23 is lowered or the angle of the reflection surface of the convex portion 23 is made gentle. Since the shape of the lens made of the transparent material 30 is changed by changing the shape of the convex portion 23 in this way, the radiation angle can be controlled.

  Next, the envelope of the light emitting element of the comparative example will be described. As shown in the perspective view of FIG. 5, the envelope of the comparative example is different from the conventional envelope shown in FIG. 8 in that the lens-shaped convex portion raised on the flat surface of the transparent resin 30 is different. It is the structure formed in the process. In this process, an inverted saddle-shaped mold is placed in the opening of the recess 21 and a transparent material 30 is injected into the mold to add a lens-shaped convex portion on the flat surface of the transparent material 30. To form. In addition, the same components as those in FIG.

  As shown in the radiation pattern of FIG. 6, the envelope of the comparative example also has a narrow radiation angle. However, the convex portion of the comparative example must be continuously adhered on the flat surface of the transparent material 30 without a sense of incongruity, which increases the number of difficult processes and increases the manufacturing cost.

  Therefore, according to the present embodiment, the convex portion 23 that is higher than the depth of the concave portion 21 and has a reflective surface on the side wall is disposed at the center of the concave portion 21 of the package 20, and the light emitting element 1 and the convex portion are disposed in the concave portion 21. By injecting the transparent material 30 having viscosity from the convex portion 23 so as to cover the surface 23, the transparent material 30 is formed into a raised lens shape, so that the radiation angle can be changed. And by adjusting the angle and height of the reflective surface of this convex part 23, since the shape of the lens by the transparent material 30 changes, a radiation angle can be controlled easily. Further, since the transparent material 30 is injected while adhering to the convex portion 23 in a viscous manner in the manufacturing process and remains in the concave portion 21 while forming a lens shape, the process of injecting the transparent material 30 into the concave portion 21 can be performed only once. It becomes possible. Therefore, the radiation angle can be controlled without adding a complicated manufacturing process.

  According to the present embodiment, since the upper portion of the convex portion 23 is a flat surface, the injected transparent material 30 is received by this flat surface, and the transparent material 30 gradually changes from the convex portion 23 to the concave portion 21 due to viscosity. Since it flows and stays, the transparent material 30 can be reliably formed into a raised lens shape.

  According to the present embodiment, since the convex portion 23 has a simple shape like a truncated cone, the convex portion 23 can be formed on the bottom surface of the concave portion 21 by a single step by injection molding using a mold. The convex portion 23 can be formed without going through a complicated process.

  In the present embodiment, the convex portion 23 has a truncated cone shape, but is not limited thereto. For example, as shown in the perspective view of FIG. 7, the convex portion 24 may be cylindrical. As described above, even when the convex portion 24 is cylindrical, since the upper portion is a flat surface, the injected transparent material 30 can be received, and the transparent material can be reliably formed into a raised lens shape. . In addition, by adopting a simple shape such as a cylindrical shape, the convex portion 24 can be formed on the bottom surface of the concave portion 21 by a single process by injection molding using a mold, and the convex portion can be formed without going through a complicated process. 24 can be formed. In FIG. 7, the same components as those in FIG. 1 are denoted by the same reference numerals, and redundant description is omitted.

It is a perspective view which shows the structure of the envelope of the light emitting element in one Embodiment. It is sectional drawing which shows the structure of the envelope of the said light emitting element. It is a figure which shows the radiation pattern of the envelope of the said light emitting element. It is sectional drawing for demonstrating the control method of the radiation angle in the envelope of the said light emitting element. It is a perspective view which shows the structure of the envelope of the light emitting element of a comparative example. It is a figure which shows the radiation pattern of the envelope of the light emitting element of a comparative example. It is a perspective view which shows the structure of the envelope of the light emitting element in another embodiment. It is a perspective view which shows the structure of the envelope of the conventional light emitting element. It is sectional drawing which shows the structure of the envelope of the conventional light emitting element. It is a figure which shows the radiation pattern of the envelope of the conventional light emitting element. It is a perspective view which shows the structure of the envelope which mounts the conventional several light emitting element.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 1a, 1b, 1c ... Light emitting element 2, 2a, 2b, 2c ... Electrode 3, 3a, 3b, 3c ... Wire 11, 11a, 11b, 11c ... Lead frame 12, 12a, 12b, 12c ... Lead frame 20 ... Package 21 ... concave, 23, 24 ... convex 30 ... transparent material

Claims (3)

A recess with a reflective surface on the inner wall;
A convex portion disposed in the center of the concave portion, higher than the depth of the concave portion, and provided with a reflective surface on the side wall;
A light emitting device disposed around the convex portion in the concave portion;
A transparent material having a viscosity injected from the convex portion so as to cover the light emitting element and the convex portion in the concave portion;
An envelope of a light-emitting element, comprising:   The envelope of the light emitting device according to claim 1, wherein the convex portion has a flat surface at an upper portion. The envelope of the light emitting element according to claim 1, wherein the convex portion has a truncated cone shape or a cylindrical shape.

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