Phosphor distribution in LED lamps using centrifugal force

• US 9,041,285 B2
• Filed: 03/23/2012
• Issued: 05/26/2015
• Est. Priority Date: 12/14/2007
• Status: Active Grant

• Current Assignee: Creeled Incorporated
• Original Assignee: CREE Incorporated (Wolfspeed, Inc.)
• Inventors: Hussell, Christopher P., Emerson, David T.
• Primary Examiner(s): Hanley, Britt D
• Application Number:
  US13/429,053
• Publication Number:
  US 20120206039A1
• Time in Patent Office: 1,159 Days
• Field of Search: None
• US Class Current: 313/512
• CPC Class Codes: F21K 9/90 Methods of manufacture
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: H01L 2224/32257 the layer connector connecting to a bonding area disposed in a recess of the surface of the item
• 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 2224/73265 Layer and wire connectors
• CPC Class Codes: H01L 2924/00012 Relevant to the scope of the group, the symbol of which is combined with the symbol of this group
• 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: H01L 2924/181 Encapsulation
• CPC Class Codes: H01L 2933/0041 relating to wavelength conversion elements

Abstract

A method of manufacturing an LED lamp is disclosed. The method includes admixing an uncured curable liquid resin and a phosphor, dispensing the uncured admixture on an LED chip, centrifuging the chip and the admixture to disperse the phosphor particles in the uncured resin, and curing the resin while the phosphor particles remain distributed.

Claims

1. An apparatus for manufacturing light emitting diode lamps, said apparatus comprising:

a centrifuge comprising at least one arm, said centrifuge capable of rotating said at least one arm about an axis to produce a centrifugal force;

a cup pivotally connected to an outer end of said at least one arm, said cup comprising a mount surface to which light emitting diode (LED) chips are mounted; and

an admixture in said cup of an uncured curable resin and a plurality of phosphor particles;

wherein said cup is capable of pivoting to a position where said centrifugal force is substantially orthogonal to said mount surface and toward said LED chips, said admixture and said centrifuge such that said phosphor particles are deposited in desired positions in said uncured resin.

2. An apparatus according to claim 1, wherein said LED chips emit in the blue, ultraviolet or violet portions of the spectrum.

3. An apparatus according to claim 1, wherein said LED chips comprise a light emitting portion formed from the Group III nitride material system.

4. An apparatus according to claim 1, wherein said arm is rotating in said centrifuge.

5. An apparatus according to claim 1, further comprising at least one tray disposed in said cup, said tray comprising a plurality of structures in which LED chips can be mounted.

6. An apparatus according to claim 1, wherein the outer end of said at least one arm comprises an extension to receive said cup.

7. An apparatus according to claim 6, wherein said extension is L-shaped.