Alternating current light emitting device

• US 20040206970A1
• Filed: 04/16/2003
• Published: 10/21/2004
• Est. Priority Date: 04/16/2003
• Status: Abandoned Application

• Current Assignee: Lumileds LLC (Apollo Global Management, Inc.)
• Original Assignee: Lumileds LLC (Apollo Global Management, Inc.)
• Inventors: Martin, Paul S.
• Application Number:
  US10/417,735
• Publication Number:
  US 20040206970A1
• Time in Patent Office: Days
• US Class Current: 257/98
• CPC Class Codes: F21K 9/232 specially adapted for generating an essentially omnidirectional light distribution, e.g. with a glass bulb
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 27/156 two-dimensional arrays
• 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

Abstract

A plurality of semiconductor light emitting diodes formed on a single substrate are connected in series for use with an alternating current source. In one embodiment, the series array of light emitting diodes is directly connected to an alternating current source. In other embodiments, the series array of semiconductor light emitting diodes is mounted on a submount with integrated rectifying and filtering circuitry. The submount may be, for example, a silicon integrated circuit. In some embodiments a wavelength converting material is provided over the semiconductor light emitting diodes such that light emitted by the light emitting diodes and light emitted by the wavelength converting material mix to produce white light.

Claims

1. A device comprising:

a submount; and

a plurality of light emitting diodes formed on a single substrate, the plurality of light emitting diodes being mounted on the submount and connected in series;

wherein the plurality of light emitting diodes are directly connected to an alternating current source.

2. The device of claim 1 wherein the plurality of light emitting diodes are connected in series by interconnects formed on a surface of the plurality of light emitting diodes.

3. The device of claim 1 wherein the plurality of light emitting diodes are connected ill series by interconnects formed on or in the submount.

4. The device of claim 1 wherein the submount comprises a silicon integrated circuit.

5. The device of claim 1 wherein at least one of the light emitting diodes is a III-nitride light emitting diode.

6. The device of claim 5 wherein the III-nitride light emitting diode comprises a portion of the substrate and a plurality of semiconductor device layers, and wherein the III-nitride light emitting diode is mounted on the submount such that the plurality of semiconductor device layers are disposed between the submount and the portion of the substrate.

7. The device of claim 1 further comprising at least one wavelength converting material overlying at least one of the light emitting diodes.

8. The device of claim 7 wherein light emitted from the light emitting diodes mixed with light emitted from the at least one wavelength converting material appears white.

9. The device of claim 1 further comprising:

a plurality of leads electrically connected to the submount; and

a lens overlying the plurality of light emitting devices;

wherein the alternating current source is connected to the plurality of leads.

10. The device of claim 1, wherein alternating current source has a peak voltage of at least 100 volts.

11. The device of claim 1, wherein the alternating current source has an rms voltage of at least 120 volts.

12. The device of claim 1, wherein the submount is connected to a base capable of being connected to a light bulb socket.

13. The device of claim 12, wherein the base is an Edison base.

14. The device of claim 1, wherein the submount is connected to a base capable of being connected to an alternating current outlet socket.

15. The device of claim 14, wherein the base is an MR16 base.

16. A device comprising:

a submount; and

a plurality of light emitting diodes formed on a single substrate, the plurality of light emitting diodes being mounted on the submount and connected in series;

a rectifying and filtering circuit formed in the submount and connected to the plurality of light emitting diodes.

17. The device of claim 16 wherein at least one of the light emitting diodes is a III-nitride light emitting diode.

18. The device of claim 17 wherein the III-nitride light emitting diode comprises a portion of the substrate and a plurality of semiconductor device layers, and wherein the III-nitride light emitting diode is mounted on the submount such that the plurality of semiconductor device layers are disposed between the submount and the portion of the substrate.

19. The device of claim 16 further comprising at least one wavelength converting material overlying at least one of the light emitting diodes.

20. The device of claim 19 wherein light emitted from the light emitting diodes mixed with light emitted from the at least one wavelength converting material appears white.

21. The device of claim 16 wherein the rectifying and filtering circuit comprises a capacitor.

22. The device of claim 16 wherein the rectifying and filtering circuit comprises a full wave bridge rectifier.

23. A method of operating a light emitting device, the method comprising:

providing a plurality of semiconductor light emitting diodes formed on a single substrate and connected in series; and

supplying an alternating current source to the plurality of semiconductor light emitting diodes.

24. The method of claim 23 wherein the plurality of semiconductor light emitting diodes are physically mounted on and electrically connected to a submount, and supplying an alternating current source to the plurality of semiconductor light emitting diodes comprises supplying an alternating current source to the submount.