JP2011082283A - Led light emitting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a high-power LED light emitting device having a constant voltage diode element withstanding electrostatic voltage and preventing occurrence of variations or unevenness in luminescent color and emission luminance. <P>SOLUTION: The LED light emitting device 11 includes a substrate 12, a light emitting element 15 mounted on the substrate 12, a constant voltage diode element 16 mounted close to the light emitting element 15, and a translucent sealer 17 containing a photoexciting agent sealing the light emitting element 15 and the constant voltage diode element 16 and exciting light generated from the light emitting element 15. The constant voltage diode element 16 is formed to have transparency. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a high-power LED light-emitting device having electrostatic withstand voltage characteristics.

  2. Description of the Related Art Conventionally, an LED light-emitting device is configured by mounting a light-emitting element on a substrate on which an electrode pattern is formed by die bonding or wire bonding, and then sealing with a resin body having translucency (Patent Document 1). .

  FIG. 6 shows the structure of the LED light emitting device 1 of the high output type used for illumination among the LED light emitting devices. The LED light emitting device 1 includes a rectangular substrate 2 on which two electrodes 3 and 4 are formed by a cathode and an anode, a light emitting element 5 mounted on the substrate 2, and a proximity to the light emitting element 5. The constant voltage diode element 6 to be mounted and a sealing body 7 made of a translucent resin for sealing the light emitting element 5 and the constant voltage diode element 6 are configured.

  The constant voltage diode element 6 is provided to protect the light emitting element 5 from a surge caused by static electricity, and can stably drive the light emitting element 5 for lighting use in which a high current flows.

JP 2002-111073 A

  In the LED light emitting device 1, as shown in FIG. 7A, since the constant voltage diode element 6 is disposed close to the light emitting element 5, a part of the light emitted from the light emitting element 5 is a constant voltage diode. Variations or unevenness in light emission may occur due to being blocked or reflected by the element 6. FIG. 7 (b) shows the directivity of light emission of the LED light emitting device 1. The luminance of the LED light emitting device 1 as a whole gradually decreases with the center of the light emitting element 5 as a peak, but the anode side on which the electrode 4 is located is closer to the cathode side on which the electrode 3 is located. The reduction rate is increased due to the presence of the constant voltage diode element 6.

  Further, in the case of an LED light emitting device that emits light by converting the light emitted from the light emitting element 5 into white or an intermediate color by dispersing a fluorescent agent in the sealing body 7 that seals the light emitting element 5, Due to the influence of the constant voltage diode element 6 disposed in the stationary body 7, there may be variations or unevenness in the emission color and emission luminance.

  Since the constant voltage diode element 6 is formed of colored silicon resin itself, it absorbs or reflects light emitted from the light emitting element 5, and therefore the portion where the constant voltage diode element 6 is disposed. May become locally dark or shadowed.

  Conventionally, in order to improve such a problem, the constant voltage diode element is mounted on the front surface of the substrate or the back surface side of the substrate separated from the sealing body in which the light emitting element is sealed. However, if the constant voltage diode element is separated from the light emitting element, a sufficient effect of absorbing electrostatic surge cannot be obtained. In addition, since the light emitting element and the constant voltage diode element are separated from each other, there is a problem that the substrate size becomes large and the wiring pattern becomes long, and miniaturization is restricted.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a high-power LED light-emitting device that includes a constant-voltage diode element for electrostatic withstand voltage, and does not cause variation or unevenness in light emission color or light emission luminance. Is to provide.

  In order to solve the above-described problems, an LED light emitting device of the present invention includes a substrate, a light emitting element mounted on the substrate, a constant voltage diode element mounted in proximity to the light emitting element, the light emitting element, and the light emitting element. In the LED light emitting device configured to seal the constant voltage diode element and include a light-transmitting sealing body containing a photoexciter that excites light emitted from the light emitting element, the constant voltage diode element Is formed with transparency.

  According to the LED light emitting device of the present invention, since the constant voltage diode element mounted close to the light emitting element has transparency, the light emitted from the light emitting element is blocked by the constant voltage diode element. , No reflection. For this reason, it has become possible to provide an LED light-emitting device that can be driven with uniform and high output while having sufficient electrostatic withstand voltage.

  Further, in the LED light emitting device having a structure in which the light emission color is converted by dispersing the photoexciter in the sealed body, since the constant voltage diode element has transparency, There is no bias in the photoexcitation action, and it is possible to obtain white light emission or intermediate color light emission with no variation or unevenness.

1 is a perspective view of an LED light emitting device according to the present invention. It is sectional drawing of the said LED light-emitting device. It is sectional drawing which shows the structure of a light emitting element. It is a circuit diagram of the said LED light-emitting device. It is the top view (a) and light emission characteristic figure (b) of the said LED light-emitting device. It is a perspective view of the conventional LED light-emitting device. It is the top view (a) and light emission characteristic figure (b) of the said conventional LED light-emitting device.

  Hereinafter, embodiments of an LED light emitting device according to the present invention will be described in detail with reference to the accompanying drawings. As shown in FIGS. 1 and 2, the LED light emitting device 11 of the present invention is mounted on a rectangular substrate 12 having a pattern of a pair of electrodes (cathode electrode 13 and anode electrode 14) and the substrate 12. A light emitting element 15, a constant voltage diode element 16 mounted close to the light emitting element 15, and a translucent transparent resin or translucent resin that seals the light emitting element 15 and the constant voltage diode element 16. A sealing body 17 is provided.

  The substrate 12 is formed in a rectangular shape with an insulating material such as a general epoxy resin or BT resin, and a mounting area for mounting the light emitting element 15 and the constant voltage diode element 16 is provided at the center. A cathode electrode 13 and an anode electrode 14 are formed in a direction facing each other with the electrode interposed therebetween.

  As the light emitting element 15, a high output type blue light emitting element (blue LED) made of a gallium nitride compound semiconductor is used in order to emit white light emission color for general illumination. As shown in FIG. 3, the blue LED is composed of a substrate 21 made of sapphire glass and a diffusion layer 27 in which an n-type semiconductor 22 and a p-type semiconductor 23 are diffused and grown on the substrate 21. . Each of the n-type semiconductor 22 and the p-type semiconductor 23 includes an n-type electrode 24 and a p-type electrode 25, and is connected to the cathode electrode 13 and the anode electrode 14 provided on the substrate 12 by a bonding wire, and has a constant current. As a result, blue light is emitted from the light emitting layer 26.

  The constant voltage diode element 16 is also called a Zener diode, and is provided to protect the light emitting element 15 from a surge caused by static electricity. As shown in FIG. 4, the light emitting element 15 is in a reverse direction. Connected in parallel. By adding this constant voltage diode element 16, even when a reverse polarity electrostatic voltage is applied to the light emitting element 15, static electricity of 0.6 V or more flows to the constant voltage diode element 16 side and is consumed. Therefore, the light emitting element 15 is protected.

  As shown in FIG. 2, the constant voltage diode element 16 has a structure having a diffusion layer 32 in which an n-type semiconductor and a p-type semiconductor are diffused and grown on a substrate 31 in the same manner as a normal rectifying diode element. It has become. A characteristic point of the present invention is that the substrate 31 or the diffusion layer 32 is made of a transparent member or a transparent oxide so that the constant voltage diode element 16 has transparency.

  The sealing body 17 covers and protects the light emitting element 15 and the constant voltage diode element 16 by filling a mold disposed on the substrate 12 with a transparent or translucent resin material having translucency. ing. The sealing body 17 in this embodiment is made of epoxy resin or silicon resin base material, yttrium aluminum garnet (hereinafter referred to as YAG for short), which is a raw material of fluorescent particles that are one of photoexciters, and pigment particles. An appropriate amount of each dye as a raw material is mixed, and these are uniformly dispersed.

  Therefore, when a current flows between the cathode electrode 13 and the anode electrode 14 of the LED light-emitting device 11, as shown in FIG. 3, the boundary surface (light-emitting layer) 26 between the n-type semiconductor 22 and the p-type semiconductor 23 is formed. Blue light is emitted, and this blue light emission is directed upward, laterally, and downward. In particular, the blue light emitted upward excites the fluorescent particles dispersed in the sealing body 17, so that the wavelength-converted white light having a wide wavelength is transmitted in all directions in the sealing body 17. To spread.

  According to the LED light emitting device 11 of the present invention, as shown in FIG. 5A, the constant voltage diode element 16 is disposed in the same sealing body 17 in the vicinity of the light emitting element 15. Since the diode element 16 has translucency, most of the light emitted from the light emitting element 15 can be transmitted. For this reason, as shown in FIG. 5B, the luminance with the peak at the center of the light emitting element 15 is attenuated between the cathode side where the electrode 13 is located and the anode side where the electrode 14 is located. The amount is substantially uniform. In addition, since the fluorescent agent dispersed in the sealing body 17 is excited substantially uniformly, the entirety including the peripheral portion where the constant voltage diode element 16 is mounted has the same emission color and emission luminance. Further, since the constant voltage diode element 16 has translucency, the shadowed portion of the light emitting element 15 is greatly reduced, and local unevenness in the emission color and emission luminance can be suppressed.

  As described above, according to the LED light emitting device 11 of the present invention, since the constant voltage diode element 16 is mounted close to the light emitting element 15, it is possible to effectively prevent the surge from entering due to static electricity. At the same time, the emission color and emission luminance can be made uniform. Therefore, it is most suitable for lighting devices and lighting units that require high output and high reliability, such as in-vehicle headlamps, as well as indoor general lighting.

  In addition, although the said embodiment demonstrated the chip-type LED light-emitting device directly mounted on the motherboard, it can be applied also to a lead frame type. That is, after fixing a blue light-emitting element chip made of a gallium nitride compound semiconductor on a pedestal on which a light-emitting element or a light-transmitting constant voltage diode element is mounted, a fluorescent light is placed in a shell-shaped sealing body. White light emission can be obtained by dispersing an appropriate amount of a photoexciter such as particles or pigment particles.

DESCRIPTION OF SYMBOLS 1 LED light-emitting device 2 Board | substrate 3, 4 Electrode 5 Light emitting element 6 Constant voltage diode element 7 Sealing body 11 LED light emitting apparatus 12 Board | substrate 13, 14 Electrode 15 Light emitting element 16 Constant voltage diode element 17 Sealing body 21 Substrate 22 N type Semiconductor 23 p-type semiconductor 24 n-type electrode 25 p-type electrode 26 Light emitting layer 27 Diffusion layer 31 Substrate 32 Diffusion layer

Claims (4)

A substrate, a light emitting element mounted on the substrate, a constant voltage diode element mounted in proximity to the light emitting element, the light emitting element and the constant voltage diode element are sealed, and emitted from the light emitting element In the LED light emitting device configured to include a light-transmitting sealing body containing a photoexciter that excites light,
The LED light emitting device, wherein the constant voltage diode element is formed to have transparency.   The constant voltage diode element includes a substrate, and a diffusion layer made of an n-type semiconductor and a p-type semiconductor that is diffused and grown on the substrate, and at least one of the substrate and the diffusion layer is transparent. The LED light-emitting device according to claim 1.   The LED light-emitting device according to claim 1, wherein the light-emitting element is a blue light-emitting element obtained by diffusing and growing an n-type semiconductor and a p-type semiconductor on sapphire glass.   The LED light-emitting device according to claim 1, wherein the sealing body contains a photoexciter that converts light having a wavelength emitted from the blue light-emitting element into white light.

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