High power light emitting diode

• US 6,903,380 B2
• Filed: 04/11/2003
• Issued: 06/07/2005
• Est. Priority Date: 04/11/2003
• Status: Active Grant

• Current Assignee: Akron Brass Company (Comfidex Corp.)
• Original Assignee: Weldon Technologies, Inc.
• Inventors: Barnett, Thomas J., Tillinghast, Sean P.
• Primary Examiner(s): Prenty, Mark V.
• Application Number:
  US10/411,707
• Publication Number:
  US 20040201025A1
• Time in Patent Office: 788 Days
• Field of Search: 257 98-100
• US Class Current: 257/98
• 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: F21L 4/027 the light sources being a LED
• CPC Class Codes: F21S 43/14 Light emitting diodes [LED]
• CPC Class Codes: F21V 17/14 Bayonet-type fastening
• CPC Class Codes: F21V 19/0015 Fastening arrangements intended to retain light sources
• CPC Class Codes: F21V 3/04 characterised by materials, surface treatments or coatings
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• 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: H01L 2924/01046 Palladium [Pd]
• CPC Class Codes: H01L 2924/01078 Platinum [Pt]
• CPC Class Codes: H01L 2924/01079 Gold [Au]
• CPC Class Codes: H01L 2924/12041 LED
• CPC Class Codes: H01L 2924/19041 being a capacitor
• CPC Class Codes: H01L 2924/3025 Electromagnetic shielding
• CPC Class Codes: H01L 33/58 Optical field-shaping elements
• CPC Class Codes: H01L 33/62 Arrangements for conducting electric current to or from the semiconductor body, e.g. lead-frames, wire-bonds or solder balls
• CPC Class Codes: H01R 12/714 with contacts abutting directly the printed circuit; Button contacts therefore provided on the printed circuit
• CPC Class Codes: H05K 2201/10106 Light emitting diode [LED]
• CPC Class Codes: H05K 2201/10325 : Sockets, i.e. female type connectors comprising metallic connector elements integrated in, or bonded to a common dielectric support
• CPC Class Codes: H05K 3/301 : by means of a mounting structure H05K3/325 takes precedence

Abstract

A method and system are taught for a system comprising an LED package. The LED package may comprise a leadframe having an annular contact and a base contact. An LED die may be coupled to the annular and base contacts such that the P-type material portion is electrically connected to an annular contact and the N-type material portion is electrically connected to a base contact. Alternatively the N-type material portion may be electrically connected to the annular contact and the P-type material portion may be electrically connected to the base contact. A lens may be coupled to the leadframe, and an optical material may be located in a cavity defined by the lens, the base contact, and the annular contact. The optical material may be a gel, a grease, a resilient material, a non-resilient material, a rigid material, a liquid material or a non-liquid material. The method and system may further comprise a mounting device, wherein the LED package is mechanically coupled to the mounting device in a socket, bayonet, or threaded fashion. The method and system may further comprise a strip comprising an array of annular contacts utilized to form an array of the LED packages and a carrier strip comprising receiving devices to receive the array of LED packages. A portion of the lens may either be coated with or comprise light excitable material or the optical material may comprise light excitable material, such that the system emits white light.

Claims

1. A system comprising an LED package, the LED package comprising:

an annular contact;

a base contact coupled to the annular contact to form a leadframe;

an LED die coupled to the base contact and the annular contact;

a lens coupled to the leadframe; and

an optical material located in a cavity defined by the lens, the base contact, and the annular contact.

2. The system of claim 1 wherein the annular contact is an anode.

3. The system of claim 1 wherein the annular contact is a cathode.

4. The system of claim 1 further comprising a mounting device, wherein the LED package is mechanically coupled to the mounting device via the lens.

5. The system of claim 1, further comprising a light fixture.

6. The system of claim 1 further comprising:

an anode strip comprising an array of anodes utilized to form an array of the LED packages; and

a carrier strip comprising receiving devices to receive the array of LED packages.

7. The system of claim 1 wherein the annular contact and the lens comprise complementary coupling devices for matingly engaging the annular contact and lens to one another.

8. The system of claim 7 wherein the complementary coupling devices are annular contact barbs and lens openings.

9. The system of claim 1 wherein the lens is coupled to the leadframe with an adhesive.

10. The system of claim 1 wherein the LED die is comprised of a plurality of LED dice.

11. The system of claim 10 wherein the annular contact is separated into two or more segments to provide isolated electrical contact to each LED die.

12. The system of claim 10 wherein the LED die is electrically insulated from the base contact and the LED die contains both P-type and N-type contacts on the top surface of the die such that the LED die can be electrically connected in series via wire bonding.

13. The system of claim 1 wherein the LED die is coupled to the base contact via a thermally and electrically conductive epoxy or solder and the LED die is coupled to the annular contact via wire bonding.

14. The system of claim 1 wherein the base contact further comprises a heat sink.

15. The system of claim 1 wherein the base contact further comprises a die cup into which the LED die is coupled.

16. The system of claim 1 wherein the annular contact and base contact are coupled together with liquid crystal polymer to form a leadframe.

17. The system of claim 1 wherein a portion of the lens comprises light excitable material such that the system emits white light.

18. The system of claim 1 wherein a portion of the lens comprises dispersants to diffuse output light.

19. The system of claim 1 wherein the optical material is a non-resilient material.

20. The system of claim 1 wherein the optical material is a grease.

21. The system of claim 1 wherein the optical material is a non-liquid material.

22. The system of claim 1 wherein the optical material is a resilient material.

23. The system of claim 1 wherein the optical material is a rigid material.

24. The system of claim 1 wherein the optical material is a liquid material.

25. The system of claim 1 wherein the optical material is a silicone material.

26. The system of claim 1 wherein the optical material is a UV stable material.

27. The system of claim 1 wherein the cavity is filled with the optical material.

28. The system of claim 1 wherein the optical material comprises a light excitable material.

29. The system of claim 28 where a white light is produced by the light excitable material.

30. The system of claim 1 wherein a portion of the lens is coated with light excitable material such that the system emits white light.

31. The system of claim 1 wherein the system is incorporated into an automotive signaling device.

32. The system of claim 1 wherein the system is incorporated into a flashlight device.

33. The system of claim 1 further comprising a socket device that is mounted on a printed circuit board, wherein the lens is mechanically coupled to the socket device via lens protrusions and securely biased in the socket device by flexible extensions extending from the annular contact.

34. The system of claim 1 wherein the base contact comprises a threaded portion, wherein the threaded portion is used to couple the LED package to the system.

35. The system of claim 1 further comprising:

a mounting device; and

protrusions adjacent an attachment end of the base contact,

wherein the LED package is mechanically mounted to the mounting device via the protrusions.

36. The system of claim 1 wherein the lens comprises an optical geometry to diffuse illumination from the LED die.

37. The system of claim 1 wherein the lens comprises an optical pattern to diffuse illumination from the LED die.

38. The system of claim 1 wherein the lens comprises an optical geometry to produce a desired light pattern.

39. The system of claim 1 wherein the lens comprises an optical pattern to produce a desired light pattern.

52. The system of claim 1 wherein the annular contact further comprises flexible extensions.

53. The system of claim 52 wherein the flexible extensions each have a differing diametral pitch.

40. A system comprising:

a mounting device; and

an LED package, the LED package comprising;

a leadfrarne comprising;

an annular contact with a central opening;

a base contact having heat sink, coupled to the annular contact adjacent the central opening;

an LED die coupled to the base contact and via wire bonding to the annular contact;

a lens coupled to the leadframe, the lens comprising protrusions that are utilized to mechanically secure the LED package to the mounting device; and

optical material located in a cavity defined by the lens and the leadframe.

41. The system of claim 40 wherein the optical material is a non-resilient material.

42. The system of claim 40 wherein the optical material is a grease.

43. The system of claim 40 wherein the optical material is a non-liquid material.

44. The system of claim 40 wherein the optical material is a resilient material.

45. The system of claim 40 wherein the optical material is a rigid material.

46. The system of claim 40 wherein the optical material is a liquid material.

47. The system of claim 40 wherein the optical material is a silicone material.

48. The system of claim 40 wherein the optical material is a UV stable material.

49. A system comprising an LED package, the LED package comprising:

an annular contact;

a base contact coupled to the annular contact to form a leadframe;

an LED die coupled to the base contact and the annular contact;

a lens coupled to the leadframe; and

a cavity defined by the lens, the base contact, and the annular contact.

50. The system of claim 49 further comprising a material in the cavity.

51. The system of claim 50, wherein the material is one of a resilient, rigid, non-resilient, grease, liquid and non-liquid material.