Anti-reflective coatings for light bulbs

• US 8,471,445 B2
• Filed: 08/14/2009
• Issued: 06/25/2013
• Est. Priority Date: 08/18/2008
• Status: Expired due to Fees

• Current Assignee: Switch Bulb Company, Inc.
• Original Assignee: Switch Bulb Company, Inc.
• Inventors: Lenk, Ronald J.
• Primary Examiner(s): Mai, Anh
• Assistant Examiner(s): FEATHERLY, HANA SANEI
• Application Number:
  US13/059,394
• Publication Number:
  US 20110193465A1
• Time in Patent Office: 1,411 Days
• Field of Search: 313/512, 313110-116
• US Class Current: 313/110
• CPC Class Codes: F21K 9/232 specially adapted for generating an essentially omnidirectional light distribution, e.g. with a glass bulb
• CPC Class Codes: F21K 9/60 Optical arrangements integrated in the light source, e.g. for improving the colour rendering index or the light extraction
• CPC Class Codes: F21V 29/58 characterised by the coolants
• CPC Class Codes: F21V 3/00 Globes; Bowls; Cover glasses with refracting properties F21V5/00; with reflecting properties F21V7/00; characterised by cooling arrangements F21V29/506
• CPC Class Codes: F21V 3/12 the coatings comprising photoluminescent substances
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: H01J 61/35 provided with coatings on the walls thereof; Selection of materials for the coatings using coloured coatings H01J61/40; using luminescent coatings H01J61/42
• CPC Class Codes: H01K 1/325 Reflecting coating

Abstract

A light bulb having anti-reflective coatings on an inner surface and/or an outer surface of the shell of the light bulb. The anti-reflective coatings reduce light loss due to reflections at the interfaces between the interior of the bulb and the shell and between the shell and the exterior of the bulb. The light source may be either incandescent, fluorescent or LED.

Claims

1. An incandescent bulb comprising:

an incandescent filament;

a shell surrounding said filament, wherein the shell has a shell index of refraction;

an anti-reflective coating on an inner surface of the shell, wherein the anti-reflective coating has an inner surface index of refraction; and

wherein the shell index of refraction and the inner surface index of refraction in combination matches an index of refraction of an inner portion of the bulb.

2. The incandescent bulb as set forth in claim 1, wherein the shell is glass.

3. The incandescent bulb as set forth in claim 1, wherein the shell is partially evacuated.

4. The incandescent bulb as set forth in claim 1, wherein the shell is a bulb-shaped shell.

5. An incandescent bulb comprising:

an incandescent filament;

a shell surrounding said filament, wherein the shell has a shell index of refraction;

an anti-reflective coating on an outer surface of the shell, wherein the anti-reflective coating has an outer surface index of refraction; and

wherein the shell index of refraction and the outer surface index of refraction in combination matches an index of refraction of an external atmosphere.

6. The incandescent bulb as set forth in claim 5, wherein the shell is glass.

7. The incandescent bulb as set forth in claim 5, wherein the shell is partially evacuated.

8. The incandescent bulb as set forth in claim 5, wherein the shell is a bulb-shaped shell.

9. An incandescent bulb comprising:

an incandescent filament;

a shell surrounding said filament, wherein the shell has a shell index of refraction;

an anti-reflective coating on an inner surface of the shell, wherein the anti-reflective coating has an inner surface index of refraction;

another anti-reflective coating on an outer surface of the shell, wherein the other anti-reflective coating has an outer surface index of refraction; and

wherein;

the shell index of refraction and the inner surface index of refraction in combination matches an index of refraction of an inner portion of the bulb, and

the shell index of refraction and the outer surface index of refraction in combination matches an index of refraction of an external atmosphere.

10. The incandescent bulb as set forth in claim 9, wherein the shell is glass.

11. The incandescent bulb as set forth in claim 9, wherein the shell is partially evacuated.

12. The incandescent bulb as set forth in claim 9, wherein the shell is a bulb-shaped shell.

13. A fluorescent bulb comprising:

a tube having a tube index of refraction;

one or more substances inside the tube, at least one of which fluoresces when properly excited;

a phosphorescent material lining the inside of the tube that converts the fluorescent radiation into visible radiation;

an anti-reflective coating on an outer surface of the tube, wherein the anti-reflective coating has an outer surface index of refraction; and

wherein the tube index of refraction and the outer surface index of refraction in combination matches an index of refraction of an external atmosphere.

14. The fluorescent bulb as set forth in claim 13, wherein the tube is glass.

15. The fluorescent bulb as set forth in claim 13, wherein the tube is partially evacuated.

16. An LED bulb comprising:

one or more LEDs;

a shell surrounding said one or more LEDs, wherein the shell has a shell index of refraction;

an anti-reflective coating on an inner surface of the shell, wherein the anti-reflective coating has an inner surface index of refraction; and

wherein the shell index of refraction and the inner surface index of refraction in combination matches an index of refraction of an inner portion of the bulb.

17. The LED bulb as set forth in claim 16, wherein the shell is glass.

18. The LED bulb as set forth in claim 16, wherein the shell is plastic.

19. The LED bulb as set forth in claim 16, wherein the shell is at least partially filled with air.

20. The LED bulb as set forth in claim 16, wherein the shell is at least partially filled with a fluid.

21. The LED bulb as set forth in claim 16, wherein the shell is at least partially filled with a gel.

22. The LED bulb as set forth in claim 16, wherein the shell is at least partially filled with a plastic material.

23. The LED bulb as set forth in claim 16, wherein the shell is a bulb-shaped shell.

24. An LED bulb comprising:

one or more LEDs;

a shell surrounding said one or more LEDs, wherein the shell has a shell index of refraction;

an anti-reflective coating on the outer surface of the shell, wherein the anti-reflective coating has an outer surface index of refraction, and

wherein the shell index of refraction and the outer surface index of refraction in combination matches an index of refraction of an external atmosphere.

25. The LED bulb as set forth in claim 24, wherein the shell is glass.

26. The LED bulb as set forth in claim 24, wherein the shell is plastic.

27. The LED bulb as set forth in claim 24, wherein the shell is at least partially filled with air.

28. The LED bulb as set forth in claim 24, wherein the shell is at least partially filled with a fluid.

29. The LED bulb as set forth in claim 24, wherein the shell is at least partially filled with a gel.

30. The LED bulb as set forth in claim 24, wherein the shell is at least partially filled with a plastic material.

31. The LED bulb as set forth in claim 24, wherein the shell is a bulb-shaped shell.

32. An LED bulb comprising:

one or more LEDs;

a shell surrounding said one or more LEDs, wherein the shell has a shell index of refraction;

an anti-reflective coating on an inner surface of the shell, wherein the anti-reflective coating has an inner surface index of refraction;

another anti-reflective coating on an outer surface of the shell, wherein the other anti-reflective coating has an outer surface index of refraction ; and

wherein;

the shell index of refraction and the inner surface index of refraction in combination matches an index of refraction of an inner portion of the bulb, and

the shell index of refraction and the outer surface index of refraction in combination matches an index of refraction of an external atmosphere.

33. The LED bulb as set forth in claim 32, wherein the shell is glass.

34. The LED bulb as set forth in claim 32, wherein the shell is plastic.

35. The LED bulb as set forth in claim 32, wherein the shell is at least partially filled with air.

36. The LED bulb as set forth in claim 32, wherein the shell is at least partially filled with a fluid.

37. The LED bulb as set forth in claim 32, wherein the shell is at least partially filled with a gel.

38. The LED bulb as set forth in claim 32, wherein the shell is at least partially filled with a plastic material.

39. The LED bulb as set forth in claim 32, wherein the shell is a bulb-shaped shell.