Omnidirectional LED Light Bulb

• US 20100314985A1
• Filed: 01/15/2009
• Published: 12/16/2010
• Est. Priority Date: 01/15/2008
• Status: Active Grant

• Current Assignee: Philip Premysler
• Original Assignee: Philip Premysler
• Inventors: Premysler, Philip
• Granted Patent: US 8,680,754 B2
• Time in Patent Office: Days
• US Class Current: 313/46
• 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 9/64 using wavelength conversion means distinct or spaced from the light-generating element, e.g. a remote phosphor layer
• CPC Class Codes: F21V 29/506 of globes, bowls or cover glasses
• CPC Class Codes: F21V 29/63 using electrically-powered vibrating means; using ionic wind
• CPC Class Codes: F21V 29/677 the fans being used for discharging
• CPC Class Codes: F21V 29/745 the fins or blades being planar and inclined with respect to the joining surface from which the fins or blades extend
• CPC Class Codes: F21V 29/75 with fins or blades having different shapes, thicknesses or spacing
• CPC Class Codes: F21V 29/76 with essentially identical parallel planar fins or blades, e.g. with comb-like cross-section
• CPC Class Codes: F21V 29/763 the planes containing the fins or blades having the direction of the light emitting axis
• CPC Class Codes: F21V 29/77 with essentially identical diverging planar fins or blades, e.g. with fan-like or star-like cross-section
• CPC Class Codes: F21V 29/80 with pins or wires
• CPC Class Codes: F21V 3/02 characterised by the shape
• CPC Class Codes: F21Y 2107/30 on the outer surface of cylindrical surfaces, e.g. rod-shaped supports having a circular or a polygonal cross section
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: G02B 19/0019 having reflective surfaces only (e.g. louvre systems, systems with multiple planar reflectors)
• CPC Class Codes: G02B 19/0061 the light source comprising a LED semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission H01L33/00

Abstract

An LED light bulb has a hollow LED support/heat sink (222, 602, 702, 900, 802, 1002, 1102, 1216, 1404, 1502, 1606, 1906) with fins (234, 406, 604, 706, 804, 904, 906,1008, 1106, 1620) extending internally and openings at two ends (230, 232, 1522). Heat generated by the LEDs (238, 908, 1242, 1624, 2504) is conducted through the heat sink fins and is removed by a convectively driven air flow that flows through the LED support/heat sink. LEDs are mounted on multiple external faces (236, 404, 910, 1524, 1622) of the LED support/heat sink thereby providing illumination in all directions. Lenses (1246, 2102, 2104) are provided for the LEDs to make the illumination highly uniform.

Claims

1. An omnidirectional LED light bulb comprising:

a first LED oriented so as to illuminate a first solid angle of 2π

steradian wherein the first LED produces a first light distribution pattern that has a first average absolute value deviation of less than 0.25 from a normalized mean intensity of 1.0 within said first solid angle;

a second LED oriented so as to illuminate a second solid angle of 2π

steradian wherein the second LED produces a second light distribution pattern that has a second average absolute value deviation of less than 0.25 from a normalized mean intensity of 1.0 within said second solid angle.

2. The omnidirectional LED light bulb according to claim 1 wherein said first LED and said second LED face in opposite directions.

3. The omnidirectional LED light bulb according to claim 2 wherein said first average absolute value deviation is less than 0.15 and said second average absolute value deviation is less than 0.15.

4. The omnidirectional LED light bulb according to claim 1 further comprising:

a base;

a hollow body coupled to said base, said hollow body comprising at least one external surface, a first opening, a second opening, and a plurality of inwardly extending heat sink fins;

wherein said first LED and said second LED are mounted on said at least one external surface between said first opening and said second opening, whereby heat generated by operating said first LED and said second LED is conducted to said plurality of inwardly extending heat sink fins and is removed by convective air flow that enters and exits said hollow body through said first opening and said second opening.

5. The omnidirectional LED light bulb according to claim 4 wherein:

said hollow body is coupled to said base by an assembly that comprises a stem and an “

X”

shaped brace.

6. The omnidirectional LED light bulb according to claim 4 comprising:

a lower assembly comprising said base and a housing, wherein said housing encloses a circuit board including an LED driver circuit.

8. The omnidirectional LED light bulb according to claim 4 wherein said hollow body is an aluminum extrusion.

10. The omnidirectional LED light bulb according to claim 8 wherein said first opening and said second opening are ends of said extrusion.

12. The omnidirectional LED light bulb according to claim 4 wherein said hollow body has a polygonal external cross sectional shape and said at least one external surface comprises a plurality of faces.

13. The omnidirectional LED light bulb according to claim 12 wherein said hollow body has a square external cross sectional shape and said at least one external surface comprises four faces.

14. The omnidirectional LED light bulb according to claim 4 further comprising a bulb shaped cover disposed over said hollow body.

15. The omnidirectional LED light bulb according to claim 14 wherein said bulb shaped cover is made from a diffusive plastic.

16. The omnidirectional LED light bulb according to claim 15 wherein said cover comprises a first cover opening and a second cover opening and wherein said first opening of said cover is proximate said first opening of said hollow body and said second opening of said cover is proximate said second opening of said hollow body.

17. The omnidirectional LED light bulb according to claim 4 wherein said hollow body comprises a plurality of segments that fit together.

18. The omnidirectional LED light bulb according to claim 17 wherein said plurality of segments are aluminum extrusions.

20. The omnidirectional LED light bulb according to claim 4 wherein said first opening is proximal to said base and said second opening is distal from said base.

21. The omnidirectional LED light bulb according to claim 5 wherein said base is an Edison type base.

39. The omnidirectional LED light bulb according to claim 14 wherein said bulb shaped cover is mounted over said hollow body in a manner such that gaps are left between said hollow body and said bulb shaped cover that allow air to flow through said bulb shaped cover proximate said external surface.

40. The omnidirectional LED light bulb according to claim 1 wherein said LED comprises a first lens and said second LED comprises a second lens wherein said first lens and said second lens are described by a differential equation DE1:

41. The omnidirectional LED light bulb according to claim 1 comprising a first lens for said first LED and a second lens for said second LED wherein at least a portion of said first lens and at least a portion of said second lens are described by a set of coupled differential equations DE2, DE3:

42. The omnidirectional LED light bulb according to claim 14 wherein said bulb shaped cover includes a phosphor.

43. The omnidirectional LED light bulb according to claim 6 wherein said hollow body is supported in spaced relation from said housing.

7. (canceled)

9. (canceled)

11. (canceled)

19. (canceled)

22-38. -38. (canceled)

44. An omnidirectional LED light bulb comprising:

an LED support/heat sink comprising a first external surface that faces a first direction that is perpendicular to a longitudinal axis of said omnidirectional LED light bulb and a second external surface that faces a second direction that is perpendicular to said longitudinal axis of the said omnidirectional LED light bulb;

a first LED mounted on said first external surface facing in said first direction;

a second LED mounted on said second external surface facing in said second direction;

a first lens for said first LED and a second lens for said second LED;

a diffuser disposed around said LED support/heat sink so as to intercept light transmitted by said first lens and said second lens;

wherein said first lens and said second lens serve to reduce light intensity along respective optical axes of said first LED and said second LED and to reduce light intensity in a polar angle range below a predetermined polar angle defined with respect to optical axes of said first LED and said second LED and serve to increase light intensity in a polar angle range above said predetermined angle; and

wherein at least said diffuser, said first lens and said second lens serve to create a light distribution that is substantially azimuthally uniform with respect to an azimuth angle defined about said longitudinal axis of said omnidirectional LED light bulb.

45. An omnidirectional LED light bulb comprising:

a lower assembly comprising a base adapted to receive electrical power and a housing, wherein said housing encloses a circuit board including an LED driver circuit;

a hollow body mounted in spaced relation to said housing providing a space between said hollow body and said housing, said hollow body comprising at least one external surface, a first opening, a second opening, and a plurality of inwardly extending heat sink fins;

wherein said first LED and said second LED are mounted on said at least one external surface between said first opening and said second opening, whereby heat generated by operating said first LED and said second LED is conducted to said plurality of inwardly extending heat sink fins and is removed by convective air flow that flows through said space and enters and exits said hollow body through said first opening and said second opening.