JPH06296043A - Light-emitting diode - Google Patents

Abstract

(57) [Summary] [Purpose] To enable mounting of three LED pellets of different colors required for full-color emission, to improve color mixing and prevent bubbles during molding. [Structure] A concave portion of the inner container 2 is molded with a resin having a high dispersant concentration, and the entire inner container 2 is molded with a resin having a low dispersant concentration to form a double mold structure in which color mixing is improved. Further, in the case of the single mold, the notch 8 is provided in the inner container 2 to improve the escape of air bubbles. [Effect] At least three LED pellets can be mounted in the concave portion of the inner container, and the color mixing property is improved by the double mold structure.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a multicolor light emitting diode.

[0002]

2. Description of the Related Art A light emitting diode uses GaP as an emission color.
Red and green using Ga-based compound semiconductors such as GaAlAs and blue, and blue using compound semiconductors such as SiC, GaN, and ZnZe. These three in recent years
There has been an increasing demand from the market for a light emitting diode capable of emitting multi-colored light by arranging LED pellets of different colors in the same surrounding encapsulant, a so-called mold.

As shown in the plan view of FIG. 6 (a) and the sectional view of FIG. 6 (b), the conventional multi-color light emitting diode has a flat portion 11a as an LED pellet mounting portion formed by pressing the tip of a metal lead frame 11. Forming the flat part 1
After forming the reflection part 11b around 1a, the mold part 12 was formed around the reflection part 11b with the sealing resin containing the light dispersant.

[0004]

In the metal lead frame 11 formed by such press working, a large area of the flat portion 11a for mounting the LED pellets cannot be secured, so that the two LED pellets 13 and 13 'are mounted. It was the limit.

Red emitting LED pellets and green emitting LEDs
In order to produce a multi-color light emitting diode that is formed by combining the three emission colors of the pellet and the blue light emitting LED pellet, it is necessary to install a flat portion on which three or more LED pellets can be mounted on the lead frame. There is also a need for a lead frame that can easily form a lighting circuit for these three or more LED pellets.

Further, when three or more LED pellets having different emission colors are mounted in the same mold, it is better to use a transparent resin for the resin forming the mold part in terms of light emission efficiency. In this case, each LED
The emission color from the pellet is directly visible.

[0007] For example, to explain using an example of emitting orange light, orange is obtained by simultaneously emitting light from LED pellets emitting red and green to mix the colors, but in the case of a transparent resin, red and green are separately obtained. Since it is emitted to the outside, the red and green are directly visible from outside.

In order to improve the color mixing performance of the luminescent color, it has been practiced to form the mold part with a semitransparent resin containing a light dispersant. However, in this case, the light emission luminance decreases in inverse proportion to the amount of the light dispersant added to the mold part.

[0009] Further, it is required in commercial products that the hue and the brightness do not change even if the mixed color light from simultaneous lighting of two or more different color light emitting LED pellets is observed from any direction.

In a light emitting diode single-molded with an encapsulating resin to which an arbitrary concentration of a light dispersant is added, as a means for improving the luminous efficiency, a method of installing a reflecting portion around the LED pellet mounting portion of the lead frame is used. The LED pellet mounting part is shown in FIG.
As shown in FIG. 4A, a so-called concave inner container 2 having a high circumference and a low LED pellet mounting portion is used, and when forming the mold portion 14 of the light emitting diode, as shown in FIG. The inner container is inserted upside down into the mold 9 filled with the stock solution 14 of the stopping resin. At this time, as shown in FIG. 4 (c), the surrounding air is entrained and the air bubbles 1
When 0 remains, and the mold sealing resin is heated and hardened, air bubbles 10 remain in the mold 14 of the light emitting diode, which is a cause of lighting failure, characteristic failure, and the like.

As described above, a lead frame is required to prevent air bubbles 10 from being generated in the mold portion 14 of the light emitting diode when the mold portion 14 is formed.

[0012]

SUMMARY OF THE INVENTION According to the present invention, an LED pellet mounting portion capable of mounting red, green and blue LED pellets is provided on a lead frame provided in an internal container formed of a thermoplastic resin. And L to this lead frame
After mounting the ED pellets, a structure is adopted in which the molding is performed so as to cover the entire inner container.

Further, as a means for taking out the emission color when two or more color LED pellets are simultaneously turned on as one mixed color, a semi-transparent resin having a first concentration with a large amount of the light dispersant added is recessed in the inner container. A double mold structure is adopted in which the upper surface is filled up and the surrounding area is molded with a second concentration semi-transparent resin containing less light dispersant.

As a structure for preventing air bubbles from staying in the inner container, an arbitrary number of cuts are provided at a depth from the upper surface of the recess to the bottom surface of the recess and from the inner surface of the recess to the outer surface. .

[0015]

The red light emitting LED pellet and the green light emitting diode which enable multi-color light emission are provided by providing an inner container having a concave portion formed of a thermoplastic resin on the lead frame instead of directly providing the concave portion on the lead frame. Luminous LE
Three different color light emitting LED pellets, a D pellet and a blue light emitting LED pellet, can be mounted in the same light emitting diode.

Further, the semi-transparent resin of the first concentration having a large amount of the light dispersant added is filled up to the upper surface of the inner container in which the LED pellets are mounted, and the periphery thereof is filled with the second concentration of the light dispersant having a small concentration. By adopting a double mold structure molded with a semi-transparent resin, it is possible to suppress a change in hue between the emission color when viewed from the front and the emission color when viewed from the oblique lateral direction.

The air inside the recess of the light emitting diode is provided by providing an arbitrary number of cuts that reach from the upper surface of the recess to the bottom surface of the recess of the inner container in which the LED pellets are mounted and reach from the inner surface to the outer surface of the recess. The bubbles are easily discharged to the outside by passing through the cut portion.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A light emitting diode of the present invention will be described with reference to the drawings.

As shown in the side sectional view of FIG. 1A, the plan view of FIG. 1B, and the perspective view of FIG. The sealing resin 6 having a high concentration of the light dispersant is filled up to the upper surface of the concave portion of the mounting portion and cured, and the periphery thereof is sealed at the second concentration with a low amount of the light dispersant added. By adopting the double mold structure in which the lens is formed of the resin 7, the contradictory performances of the emission brightness and the emission color mixing property can be compatible.

In order to realize this structure, as shown in FIG. 2 (a), a flat portion 1a for mounting an LED pellet manufactured by etching or pressing on a metal flat plate having a plate thickness of 0.1 to 0.275 mm. As shown in FIG. 2B, an inner container 2 formed of a white thermoplastic resin for the purpose of improving the light emission output in the forward direction of the LED pellet is attached to a lead frame 1 having a lead output portion 1b. Form. In addition,
The inner container 2 also plays a role of holding the lead frames 1 arranged to face each other.

The lead frame 1 manufactured as described above
In the recess of the inner container 2 of the above, it is possible to mount one red light emitting LED pellet 3, one green light emitting LED pellet 4 and one blue light emitting LED pellet 5 required for multi-color light emission, and a total of three or more LED pellets. It will be possible.

Further, as shown in the perspective view of FIG. 3, by providing a notch 8 extending from the upper surface of the recess to the bottom surface of the recess and from the inner surface of the recess to the outer surface of the recess, as compared with FIG. As shown in FIGS. 4 (a) to 4 (d), the air bubbles 10 wound inside the mold can be easily discharged to the outside through the cuts 8, and the air bubbles in the light emitting diode mold portion can be removed.

Of course, here, the width and the number of the cuts 8 should be considered in consideration of the shape and size of the inner container 2, and the viscosity of the molding sealing resin should be carefully examined. If the width of the cut is increased or the number of cuts is increased, the air bubbles will be more likely to escape, but the internal area of the recess that reflects the light of the LED pellet forward will decrease, so it will be decided appropriately so as to suppress the decrease in brightness. There is a need to.

[0024]

According to the first aspect of the present invention, a large amount of the light dispersant is added to the upper surface of the recess of the inner container of the LED pellet mounting portion of the lead frame.
Two or more different color light emitting LED pellets by filling and hardening the sealing resin 6 having a concentration of 2 and forming a lens around the sealing resin 7 having a second concentration with a small amount of the light dispersant added. When simultaneously lit, the color mixture can be improved to the extent that the color of light emitted from the light emitting diode looks the same from any direction,
Further, it is possible to suppress a decrease in light emission luminance which is contradictory to color mixing. Also, in a light-emitting diode that is single-molded with a sealing resin with an arbitrary concentration of a light dispersant, it is molded with a thermoplastic resin that has a structure that enables improved light output and mounting of three or more different color LED pellets. By providing an arbitrary number of notches 8 that reach the bottom surface of the recess from the top surface of the recess of the inner container 2 and reach from the inner surface of the recess to the outer surface, the recess of the inner container 2 is formed of the molding resin for molding. When inserting into the mold 9 filled with the stock solution, the air bubbles generated by entraining the surrounding air can be easily discharged to the outside.

[Brief description of drawings]

FIG. 1A is a sectional view of a light emitting diode according to an embodiment of the present invention, FIG. 1B is a plan view thereof, and FIG.

FIG. 2A is a plan view of a lead frame circuit unit and a lead output unit used in the light emitting diode of the embodiment of the present invention. FIG. 2B is a plan view of the lead frame in which a thermoplastic resin inner container is attached.

FIG. 3 is a perspective view of a light emitting diode according to an embodiment of the present invention.

FIG. 4 (a) is a view of forming a mold portion in the process of manufacturing an embodiment of the present invention (before insertion into a mold) (b) Similarly is a sectional view of a mold filled with a stock solution of a sealing resin for molding. ) A state diagram in which a lead frame with an envelope is also inserted into a mold (d) A sectional view showing the completion of a single mold light emitting diode

FIG. 5 (a) is a view showing a mold portion showing a manufacturing process of a conventional device (before being inserted into a mold) (b) A sectional view of a mold filled with a stock solution of a sealing resin for molding (c) Also outside Figure showing the lead frame with enclosure inserted in the mold (d) Completion drawing of the same single-mold LED

FIG. 6A is a plan view of a conventional multi-color light emitting diode, and FIG. 6B is a side view of the same.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Lead frame 1a LED pellet mounting part 1b Lead output part 2 Inner container 3 Red light emitting LED pellet 4 Green light emitting LED pellet 5,5 'Blue light emitting LED pellet 6 1st sealing resin 7 2nd sealing resin 8-8 ″ ”Notch 9 Mold filled with undiluted liquid for molding resin 10 Air bubbles 11 Metal lead frame 11a Flat portion 11b Reflecting portion 12 Mold portion 13, 13 ′ LED pellet 14 Mold portion

Claims (3)

[Claims] 1. An LED is mounted on a plurality of inner leads disposed on the bottom surface of the recess of a non-translucent inner container having the recess.
A light emitting diode, characterized in that the pellets are individually mounted, and the non-translucent inner container and the LED pellets are integrally molded by a translucent resin so as to integrally cover the LED pellets. 2. The non-translucent inner container according to claim 1 is covered with a resin to which a light dispersant has been added at a first concentration up to the upper surface of the concave portion, and the outer periphery of which is less than the first concentration. A light emitting diode characterized by being molded with a resin to which a light dispersant having a concentration of is added. 3. A light-emitting diode, wherein the inner container according to claim 1 is provided with a notch extending from the upper surface to the bottom surface of the recess and reaching from the inner side surface to the outer surface of the recess.