Solid state light source light bulb

• US 8,292,468 B2
• Filed: 06/09/2010
• Issued: 10/23/2012
• Est. Priority Date: 06/10/2009
• Status: Active Grant

• Current Assignee: Rensselaer Polytechnic Institute
• Original Assignee: Rensselaer Polytechnic Institute
• Inventors: Narendran, Nadarajah, Freyssinier, Jean Paul, Zhu, Yiting
• Primary Examiner(s): Sawhney, Hargobind S
• Application Number:
  US13/376,887
• Publication Number:
  US 20120081880A1
• Time in Patent Office: 867 Days
• Field of Search: 362/227, 362/230, 362/231, 362/238, 362/240, 362/241, 362243-245, 362/249.01, 362/249.02, 362/249.11, 362/255, 362/294, 362/304, 362/305, 362/310, 362/311.01, 362/326, 362/327, 362/329, 362/373, 362/377, 362/551, 362/555, 362/558, 362/577, 362/600, 362/606, 362/608, 362/613, 362615-617, 362/649, 362/650, 362/800, 313 44- 46, 313/317, 313/318.01, 313/318.04, 313/318.11, 313/318.12, 313485-487, 313498-504, 313/512
• US Class Current: 362/310
• 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 9/61 using light guides
• 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: F21K 9/66 Details of globes or covers forming part of the light source
• CPC Class Codes: F21V 13/14 the elements being filters or photoluminescent elements, reflectors and refractors
• CPC Class Codes: F21V 23/002 Arrangements of cables or conductors inside a lighting device, e.g. means for guiding along parts of the housing or in a pivoting arm
• CPC Class Codes: F21V 29/70 characterised by passive heat-dissipating elements, e.g. heat-sinks
• CPC Class Codes: F21V 29/74 with fins or blades
• 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 7/0008 providing for indirect lighting
• CPC Class Codes: F21V 7/0025 Combination of two or more reflectors for a single light source array of reflectors for a cluster of light sources F21V7/0083
• CPC Class Codes: F21V 9/32 characterised by the arrangement of the photoluminescent material
• CPC Class Codes: F21V 9/45 by adjustment of photoluminescent elements
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]

Abstract

A light emitting apparatus includes a lamp base, a light-transmissive bulb envelope, a light source for emitting light, and a heat sink coupled to the light source. A solid state LED light bulb may further include a down conversion material. The down conversion material is disposed within the bulb envelope, remote from the light source and between the light source and the lamp base. The heat sink may include at least one metal fin and, additionally or alternatively, include a mesh disposed over at least an outer portion of the bulb envelope. A solid state light bulb may include a light guide for directing the light emitted by the light source. The solid state light bulb configurations place the light source and heat sink at the apex of the light bulb envelope, distant from the lamp base, in order to dissipate heat produced by the light source into the environment. In addition, at least part of the heat sink is outside the light bulb envelope to maximize the heat dissipation.

Claims

1. A light emitting apparatus comprising:

a lamp base;

a light-transmissive bulb envelope, a first portion of the bulb envelope coupled to the lamp base;

a light source for emitting light, at least a portion of the light source disposed external to the bulb envelope at an end substantially opposite the lamp base;

a down conversion material for receiving and down converting at least some of the light emitted by the light source and back transferring a portion of the received and down converted light, the down conversion material disposed within the bulb envelope, remote from the light source and between the light source and the lamp base;

a reflector for receiving and reflecting the light emitted by the light source and down converted by the down conversion material, the reflector disposed within the bulb envelope between the down conversion material and the lamp base; and

a heat sink coupled to the light source, at least a portion of the heat sink external to the bulb envelope.

2. The apparatus according to claim 1 further comprising a light guide for directing the light emitted by the light source, a first end of the light guide coupled to the light source and a second end of the light guide coupled to the down conversion material.

3. The apparatus according to claim 2, wherein the light guide is either a cylinder, or a tapered cylinder, the cylinder or tapered cylinder having an upper portion selected from the group consisting of angle cut, flat, pointed, spherical, hemispherical, and conical.

4. The apparatus according to claim 1, wherein the light source is at least one light emitting diode (LED).

5. The apparatus according to claim 1, wherein at least a portion of the heat sink projects into the bulb envelope.

6. The apparatus according to claim 1, further comprising at least a second reflector for directing the light emitted from the light source, the light source disposed within the reflector.

7. The apparatus of claim 6, wherein the second reflector for directing the light emitted from the light source is selected from the group consisting of a reflector cup and an optical lens.

8. The apparatus according to claim 6, wherein the second reflector is an integral component of the heat sink.

9. The apparatus according to claim 1, wherein the light source comprises a plurality of light emitting diodes, the light emitting diodes disposed within at least one reflector.

10. The light emitting apparatus of claim 1, wherein the down conversion material comprises at least one wavelength-converting material adapted to absorb radiation in one spectral region and emit radiation in another spectral region.

11. The light emitting apparatus of claim 10, wherein the at least one wavelength-converting material is at least one phosphor.

12. The apparatus according to claim 1, wherein the reflector is adjacent the down conversion material.

13. The apparatus according to claim 1, wherein the heat sink comprises a mesh disposed over at least an outer portion of the bulb envelope.

14. The apparatus according to claim 1, further comprising an electronic driver disposed within the bulb envelope.

15. The apparatus of claim 14, wherein at least a portion of the electronic driver is disposed within the lamp base.

16. The apparatus according to claim 1, wherein the heat sink comprises a mesh disposed over at least an outer portion of the bulb envelope.

17. A light emitting apparatus comprising:

a lamp base;

a light-transmissive bulb envelope, a first portion of the bulb envelope coupled to the lamp base;

a light source for emitting light, at least a portion of the light source disposed external with the bulb envelope at an end substantially opposite the lamp base;

a down conversion material for receiving and down converting at least a portion of the light emitted by the light source and back transferring a portion of the received and down converted light, the down conversion material disposed within the bulb envelope, remote from the light source and between the light source and the lamp base;

a light guide for directing the light emitted by the light source, a first end of the light guide coupled to the light source and a second end of the light guide coupled to the down conversion material;

a reflector for receiving and reflecting the light emitted by the light source and down converted by the down conversion material, the reflector disposed within the bulb envelope between the down conversion material and the lamp base; and

a heat sink coupled to the light source, at least a portion of the heat sink external to the bulb envelope.

18. The light emitting apparatus of claim 17, wherein the light guide is a cylinder.

19. The light emitting apparatus of claim 17, wherein the light guide is a tapered cylinder.

20. The light emitting apparatus of claim 19, wherein the tapered cylinder light guide has an upper portion selected from the group consisting of angle cut, flat, pointed, spherical, hemispherical, and conical.