Light emitting diode light spreader

• US 7,172,323 B1
• Filed: 04/08/2004
• Issued: 02/06/2007
• Est. Priority Date: 04/08/2004
• Status: Active Grant

• Current Assignee: Signify North America Corporation (Signify N.V.)
• Original Assignee: Genlyte Thomas Group LLC (Signify N.V.)
• Inventors: Knoble, David W., Sales, Kenneth B.
• Primary Examiner(s): O'Shea; Sandra
• Assistant Examiner(s): Truong; Bao Q.
• Application Number:
  US10/820,950
• Time in Patent Office: 1,034 Days
• Field of Search: 362/551, 362553-556, 362/582, 362/317, 362615-629, 362/511, 362/26, 362/27, 362558-561, 362576-579, 362/610, 405/46, 405/47, 385/146, 385/901, 385/129, 385/34, 385/31, 385/36, 359708-710
• US Class Current: 362/555
• CPC Class Codes: G02B 6/001 the light being emitted along at least a portion of the lateral surface of the fibre
• CPC Class Codes: G02B 6/0048 with stepwise taper

Abstract

In order to spread the light being emitted from an LED, an LED light spreader has a light conductive end, an optical path conversion side, and a light transmitting side. The present invention enables a single LED to simulate the effect of having several discrete LEDs on a circuit board or may be configured to give the effect of having a single elongated light source.

Claims

1. A light emitting diode light spreader comprising a series of partial cylindrical lengths interposed with partial frustoconical lengths forming an elongated member having a rounded surface and a light emitting surface, said light emitting surface being substantially smooth.

2. The light emitting diode light spreader of claim 1 wherein said elongated member is comprised of a transparent material.

3. The light emitting diode light spreader of claim 1 wherein said rounded surface is coated with a reflective material.

4. The light emitting diode light spreader of claim 1 wherein said elongated member further comprises a semicircular light gathering end.

5. The light emitting diode light spreader of claim 1 wherein said light emitting surface is planar.

6. The light emitting diode light spreader of claim 1 wherein said light emitting surface is curved inward.

7. An elongated light emitting diode light spreader formed of a light-transmissible material comprising a light conductive end, an optical path conversion side, and a planar light transmitting side;

wherein said optical path conversion side is substantially rounded about a longitudinal axis of said elongated light emitting diode light spreader and has a plurality of light transmissible lengths being interposed with prismatic lengths.

8. The light emitting diode light spreader of claim 7 wherein said light spreader is comprised of a plastic translucent material.

9. The light emitting diode light spreader of claim 7 wherein said optical path conversion side is coated with a reflective material.

10. The light emitting diode light spreader of claim 7 wherein said light conductive end is planar.

11. The light emitting diode light spreader of claim 7 wherein said light conductive end is curved inward.

12. An elongated transparent member comprised of a flat side and a rounded side, wherein said rounded side has a series of sections, said sections having a first length of a constant arc radius and a second length of linearly decreasing arc radius about said flat side.

13. The transparent member in claim 12 wherein said series of sections has a final section, wherein said length of constant arc radius of said final section ends with a planar surface.

14. The transparent member in claim 12 wherein said series of sections has a final section, wherein said length of constant arc radius of said final section ends with a point.

15. The transparent member in claim 12 wherein said series of sections has in the range of approximately 3 to 300 of said sections.

16. The transparent member of claim 12 wherein said rounded side is coated with a reflective material.

17. An elongated LED light emitting diode light spreader comprised of a light-transmissible material having a light conductive end, a light emitting flat surface, and an optical path conversion means;

said optical path conversion means is a plurality of partial cylindrical lengths interposed with partial frustoconical lengths forming said flat surface.

18. The light emitting diode light spreader of claim 17 wherein said light conductive end is planar.

19. The light emitting diode light spreader of claim 17 wherein said light conductive end is curved inward.

20. The light emitting diode light spreader of claim 17 wherein said transparent substrate is plastic.

21. The light emitting diode light spreader of claim 17 wherein said optical path conversion means is coated with a reflective material.