IP Library Granted Patent US 8,728,835
Granted Patent B2
US 8,728,835 · App. 12/811,832 · Granted May 20, 2014

Light scattering by controlled porosity in optical ceramics for LEDs

Inventors: Jacobus Gerardus Boerkekamp (Eindhoven, NL); Oliver Steigelmann (Eindhoven, NL); Henricus Albertus Maria Van Hal (Vessem, NL); Johannes Francisucs Maria Cillessen (Eindhoven, NL)
Assignee: Koninklijke Philips N.V.
H01L33/502
View Patent ↗
Loading inventors, assignments & file history…
Monitor This Case
Get email alerts when status or documents change.
Order Certified Copies
Most orders are placed with the USPTO same day — all within 24 business hours.
Order via The Patent Place →
Pre-filled with this patent's details
Quick Facts
Patent No.
US 8,728,835
App. No.
12/811,832
Filed
Jul 7, 2010
Granted
May 20, 2014
Kind
B2
Art Unit
2823
USPC
438/29
Abstract

The present invention relates to a light emitting device ( 100 ) comprising at least one light emitting diode ( 101 ) and at least one porous ceramic element ( 102 ), which ceramic element ( 102 ) is arranged to receive light from the light emitting diode(s) ( 101 ). The present invention also relates to methods for the manufacture of the light emitting device ( 100 ) and of the porous ceramic element ( 102 ).

Claims (19)

1. A method for the manufacture of a light emitting device comprising:

providing a slurry comprising ceramic particles of at least one wavelength converting material and polymeric particles having a diameter of from 2 μm to 10 μm;

forming a ceramic body from said slurry;

removing said polymeric particles from said ceramic body to provide a porous ceramic element having an average pore diameter of from 2 μm to 10 μm; and

arranging said porous ceramic element to receive light from at least one light emitting diode.

2. A method according to claim 1 , wherein said ceramic particles have an average particle size of from 5 μm to 10 μm.

3. A method according to claim 1 , wherein said polymeric particles have an average diameter of from 2 μm to 5 μm.

4. A method according to claim 1 , wherein said polymeric particles comprise polystyrene or polyacrylate.

5. A method according to claim 1 , further comprising subjecting said porous ceramic element to a thermal treatment at a temperature above 1000° C.

6. A method according to claim 1 , wherein removing said polymeric particles from said ceramic body comprises applying a thermal treatment such that the polymeric particles are decomposed or oxidized.

7. A method according to claim 1 , wherein forming a ceramic body from said slurry comprises one of pressing, slip casting, tape casting, roller pressing, extruding, and injection molding.

8. A method according to claim 1 , wherein the porous ceramic element is self-supporting.

9. A method according to claim 1 , wherein the at least one light emitting diode is a blue light emitting LED and the porous ceramic element is adapted to absorb blue light, while emitting yellow light.

10. A method according to claim 2 , wherein said polymeric particles are removed by subjecting said ceramic body to a thermal treatment at a temperature up to 1000° C.

11. A method according to claim 10 , wherein during said thermal treatment, the ceramic body is sintered such that the ceramic particles are fused together.

12. A method for the manufacture of a porous ceramic element comprising:

providing a slurry comprising ceramic particles of at least one wavelength converting material and polymeric particles having a diameter of from 2 μm to 10 μm;

forming a ceramic body from said slurry; and

removing said polymeric particles from said ceramic body to provide a porous ceramic element having an average pore diameter of from 2 μm to 10 μm.

Assignments (9)
SECURITY INTEREST Recorded Jan 30, 2026
From: LUMILEDS LLC
To: WILMINGTON SAVINGS FUND SOCIETY, FSB
Reel/Frame 074572/0030 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Jul 10, 2025
From: LUMILEDS LLC
To: LUMILEDS SINGAPORE PTE. LTD.
Reel/Frame 071888/0086 →
RELEASE OF SECURITY INTEREST Recorded Jan 29, 2025
From: SOUND POINT AGENCY LLC
To: LUMILEDS LLC; LUMILEDS HOLDING B.V.
Reel/Frame 070046/0001 →
SECURITY INTEREST Recorded Jan 5, 2023
From: LUMILEDS LLC; LUMILEDS HOLDING B.V.
To: SOUND POINT AGENCY LLC
Reel/Frame 062299/0338 →
CHANGE OF NAME Recorded Oct 31, 2018
From: KONINKLIJKE PHILIPS ELECTRONICS N.V.
To: KONINKLIJKE PHILIPS N.V.
Reel/Frame 047368/0237 →
CORRECTIVE ASSIGNMENT TO CORRECT THE CONVEYING PARTY DATA PREVIOUSLY RECORDED AT REEL: 044931 FRAME: 0651. ASSIGNOR(S) HEREBY CONFIRMS THE ASSIGNMENT. Recorded Aug 13, 2018
From: KONINKLIJKE PHILIPS N.V.
To: LUMILEDS LLC
Reel/Frame 047304/0203 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Dec 21, 2017
From: KONINKLIJKE PHILIPS ELECTRONICS N.V.
To: LUMILEDS LLC
Reel/Frame 044931/0651 →
SECURITY INTEREST Recorded Jul 7, 2017
From: LUMILEDS LLC
To: DEUTSCHE BANK AG NEW YORK BRANCH, AS COLLATERAL AGENT
Reel/Frame 043108/0001 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Jul 7, 2010
From: BOEREKAMP, JACOBUS GERARDUS; STEIGGELMANN, OLIVER; VAN HAL, HENRICUS ALBERTUS MARIA; CILLESSEN, JOHANNES FRANCISCUS MARIA
To: KONINKLIJKE PHILIPS ELECTRONICS N V
Reel/Frame 024642/0253 →
Priority Claims (1)
EP 08150250 · Jan 15, 2008 · regional
Continuity (1)
Related Publication 20100276717A1 · Nov 4, 2010