White light emitting diode with yellow, green and red light emitting phosphors

• US 8,378,568 B2
• Filed: 07/14/2011
• Issued: 02/19/2013
• Est. Priority Date: 10/17/2006
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Sohn, Jong Rak, Yoon, Chul Soo, Kwak, Chang Hoon, Park, Il Woo
• Primary Examiner(s): Green, Tracie Y
• Application Number:
  US13/183,176
• Publication Number:
  US 20110266584A1
• Time in Patent Office: 586 Days
• Field of Search: 313498-512, 427/66, 427532-535, 427/539, 438 26- 29, 438/34, 438/82, 428690-691, 428/917
• US Class Current: 313/503
• CPC Class Codes: C09K 11/0883 Arsenides; Nitrides; Phosphides
• CPC Class Codes: C09K 11/7786 with alkaline earth metals
• CPC Class Codes: C09K 11/77922 Silicates
• CPC Class Codes: C09K 11/77928 Silicon Aluminium Nitrides or Silicon Aluminium Oxynitrides
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48247 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H05B 33/14 characterised by the chemical or physical composition or the arrangement of the electroluminescent material , or by the simultaneous addition of the electroluminescent material in or onto the light source
• CPC Class Codes: Y02B 20/00 Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps

Abstract

Provided is a white light emitting diode (LED) including a blue LED chip; and yellow, green, and red light emitting phosphors that are coated on the blue LED chip at a predetermined mixing ratio and converts light, emitted from the blue LED chip, into white light.

Claims

1. A white light emitting diode (LED) comprising:

a blue LED chip; and

yellow, green, and red light emitting phosphors that are coated on the blue LED chip at a predetermined mixing ratio and converts light, emitted from the blue LED chip, into white light;

wherein the yellow light emitting phosphor is a silicate-based phosphor,

wherein the green light emitting phosphor is a silicate-based phosphor composed of (Ba, Sr, Ca, Mg)2SiO4;

Eu, Re or a sulfide-based phosphor composed of (Sr, Ca)Ga2S4;

Eu, Re,

wherein the red light emitting phosphor is a nitride-based phosphor composed of (Sr, Ca, Ba)AlSiN;

Eu, Re,

wherein the Eu represents a basic doping, Re represents rare earth co-doping and the mixing ratio of the yellow, green, and red light emitting phosphors is set in the range of;

0.5≦

yellow light emitting phosphors<

1, 0.01≦

green light emitting phosphors<

0.4, and 0.01<

red light emitting phosphors<

0.1 (here, yellow light emitting phosphors+green light emitting phosphors+red light emitting phosphors=1).

2. The white LED according to claim 1, wherein the yellow, green, and red light emitting phosphors are mixed and scattered.

3. The white LED according to claim 1, wherein the yellow, green, and red light emitting phosphors are sequentially laminated in the form of layer.

4. The white LED according to claim 1, wherein the yellow, green, and red light emitting phosphors are mixed with a molding material and are then coated.

5. The white LED according to claim 4, wherein the molding material is formed of any one selected from the group consisting of silicon, hybrid, epoxy, and polyvinyl-based resin.