Light Emitting Diode Construction

• US 20080297048A1
• Filed: 11/20/2006
• Published: 12/04/2008
• Est. Priority Date: 11/24/2005
• Status: Abandoned Application

• Current Assignee: Koninklijke Philips N.V.
• Original Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Inventors: Vermeulen, Markus Cornelius
• Application Number:
  US12/094,625
• Publication Number:
  US 20080297048A1
• Time in Patent Office: Days
• US Class Current: 313/512
• CPC Class Codes: F21K 9/00 Light sources using semiconductor devices as light-generating elements, e.g. using light-emitting diodes [LED] or lasers
• CPC Class Codes: H01L 25/0753 the devices being arranged next to each other
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H01L 33/50 Wavelength conversion elements
• CPC Class Codes: H05B 45/20 Controlling the colour of the light
• CPC Class Codes: H05B 45/40 Details of LED load circuits

Abstract

A light emitting diode (LED) construction is disclosed, which comprises at least one LED unit (1); at least a first kind of LED die (3) of a first material; at least a second kind of LED die (4) of a second material; and a sealing member (5), comprising a wavelength converting material (6), wherein said at least first kind of LED die (3) is electrically addressable separately from said at least second kind of LED die (4), said at least one LED unit (1) comprises LED dies (3, 4) of both kinds, and at least one continuous portion of said sealing member (5), comprising wavelength converting material (6), is positioned to receive light emitted from both kinds of LED dies (3, 4). The LED construction further comprises means (7) for adjustment of a colour temperature resulting from said LED construction.

Claims

1. A light emitting diode (LED) construction comprising

at least one LED unit (1);

at least a first kind of LED die (3) of a first material;

at least a second kind of LED die (4) of a second material; and

a sealing member (5), comprising a wavelength converting material (6),

wherein said at least first kind of LED die (3) is electrically addressable separately from said at least second kind of LED die (4), said at least one LED unit (1) comprises LED dies (3, 4) of both kinds, and at least one continuous portion of said sealing member (5), comprising wavelength converting material (6), is positioned to receive light emitted from both kinds of LED dies (3, 4),

characterized in that said LED construction further comprises means (7) for adjustment of a colour temperature resulting from said LED construction.

2. A LED construction according to claim 1, wherein said first kind of LED die (3) is a blue LED die.

3. A LED construction according to claim 1, wherein said first material is selected from InGaN (Indium Gallium Nitride) and GaN (Gallium Nitride).

4. A LED construction according to claim 1, wherein said second kind of LED die (4) is an amber LED die.

5. A LED construction according to claim 1, wherein said second material is selected from AlInGaP (Indium Gallium Aluminum Phosphide), GaAsP (Gallium Arsenide Phosphide) and GaP (Gallium Phosphide).

6. A LED construction according to claim 1, wherein said wavelength converting material (6) is yttrium-aluminum-garnet doped with cerium, praseodymium, europium or combinations thereof, for example (YAG:

Ce), (YAG;

Ce,Pr), and (YAG;

Ce,Eu).

7. A LED construction according to claim 1, wherein said means for adjustment of a colour temperature resulting from said LED construction uses Pulse Width Modulation.

8. A LED construction according to claim 7, wherein in said Pulse Width Modulation said first kind of LED die and said second kind of LED die are together switched on for 100% of the time, said first kind of LED die being switched on for n % of the time, and said second kind of LED die being switched on for (100−

n) % of the time.

9. A method for adjustment of the colour temperature output value of a LED construction according to claim 1, comprising

setting a desired output value;

varying the intensities of said first kind of LED die (3) and said second kind of LED die (4) until said desired output value is reached.

10. Means for adjustment of a colour temperature resulting from a LED construction, said LED construction comprising

at least one LED unit (1);

at least a first kind of LED die (3) of a first material;

at least a second kind of LED die (4) of a second material; and

a sealing member (5), comprising a wavelength converting material (6),

wherein said at least first kind of LED die (3) is electrically addressable separately from said at least second kind of LED die (4), said at least one LED unit (1) comprises LED dies (3, 4) of both kinds, and at least one continuous portion of said sealing member (5), comprising wavelength converting material (6), is positioned to receive light emitted from both kinds of LED dies (3, 4).