Light emitting device

Patent metadata

Field	Value
Publication number	US-10340429-B2
Application number	US-201715460621-A
Country	US
Kind code	B2
Filing date	Mar 16, 2017
Priority date	Aug 9, 2013
Publication date	Jul 2, 2019
Grant date	Jul 2, 2019

Abstract

According to one embodiment of the present invention, the light emitting device includes an LED element, a side wall which surrounds the LED element, a phosphor layer which is fixed to the side wall with an adhesive layer therebetween, and is positioned above the LED element, and a metal pad as a heat dissipating member. The side wall includes an insulating base which surrounds the LED element and a metal layer which is formed on a side surface at the LED element side of the base, and is in contact with the metal pad and the adhesive layer. The adhesive layer includes a resin layer that includes a resin containing particles which have higher thermal conductivity than the resin or a layer that includes solder.

First claim

The invention claimed is:

1. A light-emitting device, comprising:
a light-emitting element for emitting a bluish light;
a plate-shaped phosphor layer for converting the bluish light to a yellowish light by a predetermined ratio, the phosphor layer being placed away from the light-emitting element; and
a heat dissipating member that dissipates heat generated in the phosphor layer,
wherein the phosphor layer emits a light ranging from blue color to yellow color in accordance with the predetermined conversion ratio thereof,
wherein the phosphor layer comprises a single crystal phosphor, a ceramic phosphor or a glass including phosphor particles, and
wherein the heat generated in the phosphor layer is transmitted through a metal film formed of Ag, or a metal alloy comprising Ag, and an adhesive layer adhered to the heat dissipating member, wherein the adhesive layer has a thermal conductivity of not less than 1 W/(m·K).

2. The light-emitting device, according to claim 1 , wherein the adhesive layer is formed of a solder.

3. A light-emitting device, comprising:
a light-emitting element for emitting a bluish light;
a plate-shaped phosphor layer for converting the bluish light to a yellowish light by a predetermined ratio, the phosphor layer being placed away from the light-emitting element;
a heat dissipating member that dissipates heat generated in the phosphor layer;
a reflecting member for reflecting the bluish light from the light-emitting element in a direction of the phosphor layer, and/or the yellowish light from the phosphor layer back to the phosphor layer,
wherein the phosphor layer comprises a single crystal phosphor, a ceramic phosphor or a glass including phosphor particles, and
wherein the heat generated in the phosphor layer is transmitted through a metal film formed of Ag, or a metal alloy comprising Ag, and an adhesive layer adhered to the heat dissipating member, wherein the adhesive layer has a thermal conductivity of not less than 1 W/(m·K).

4. The light-emitting device, according to claim 3 , wherein:
the reflecting member comprises a horizontal portion for reflecting the yellowish light from the phosphor layer back to the phosphor layer.

5. The light-emitting device, according to claim 4 , wherein:
the reflecting member further comprises a slanting portion for reflecting the yellowish light from the phosphor layer back to the phosphor layer.

6. The light-emitting device, according to claim 4 , wherein:
the reflecting member further comprises a vertical portion for reflecting the yellowish light from the phosphor layer back to the phosphor layer.

7. The light-emitting device, according to claim 6 , wherein:
the horizontal portion is provided along an outer edge of the phosphor layer, and the vertical portion is provided along a side surface of the phosphor layer.

8. The light-emitting device, according to claim 6 , wherein:
the reflecting member is of a common metal sheet placed on the heat dissipating member.

9. The light-emitting device, according to claim 7 , wherein:
the phosphor layer is supported by a top opening of the reflecting member.

10. A light-emitting device, comprising:
a light-emitting element for emitting a bluish light;
a plate-shaped phosphor layer for converting the bluish light to a yellowish light by a predetermined ratio, the phosphor layer being placed away from the light-emitting element;
a first heat dissipating member configured to dissipate heat generated in the phosphor layer; and
a second heat dissipating member configured to dissipate heat generated by the light-emitting element,
wherein the heat generated in the phosphor layer is transmitted through a metal film formed of Ag, or a metal alloy comprising Ag, and an adhesive layer adhered to the first heat dissipating member, wherein the adhesive layer has a thermal conductivity of not less than 1 W/(m·K).

11. The light-emitting device according to claim 10 , wherein the adhesive layer is formed of a solder.

12. The light-emitting device according to claim 10 , wherein the phosphor layer comprises a single crystal phosphor, a ceramic phosphor, or a glass including phosphor particles.

13. The light-emitting device according to claim 11 , wherein the phosphor layer comprises a single crystal phosphor, a ceramic phosphor, or a glass including phosphor particles.

14. The light-emitting device according to claim 10 , wherein the light-emitting element is a face-down type LED comprising a substrate and a crystal layer, and wherein the crystal layer is positioned on the second heat dissipating member opposite to the phosphor layer.

Assignees

• Koha Co Ltd
• Tamura Seisakusho Kk
• Nat Inst Materials Science

Inventors

• Inomata Daisuke
• Sano Hiroaki
• Yoshida Seitaro
• Aoki Kazuo
• Shimamura Kiyoshi
• Garcia Villora Encarnacion Antonia

Classifications

• H10W90/756

  between a chip and a stacked lead frame, conducting package substrate or heat sink · CPC title

• H10W90/754

  between a chip and a stacked insulating package substrate, interposer or RDL · CPC title

• H10W90/736

  between a chip and a stacked lead frame, conducting package substrate or heat sink · CPC title

• H10W90/734

  between a chip and a stacked insulating package substrate, interposer or RDL · CPC title

• H10W90/00

  Package configurations · CPC title