LED light bulb with controlled color distribution using quantum dots

• US 8,591,069 B2
• Filed: 09/21/2011
• Issued: 11/26/2013
• Est. Priority Date: 09/21/2011
• Status: Expired due to Fees

• Current Assignee: Switch Bulb Company, Inc.
• Original Assignee: Switch Bulb Company, Inc.
• Inventors: Horn, David
• Primary Examiner(s): Hanley, Britt D
• Application Number:
  US13/239,288
• Publication Number:
  US 20130070450A1
• Time in Patent Office: 797 Days
• Field of Search: None
• US Class Current: 362/294
• CPC Class Codes: B82Y 20/00 Nanooptics, e.g. quantum optics or photonic crystals
• 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 29/503 of light sources cooling arrangements structurally associated with gas-discharge or vapour-discharge lamps H01J61/52; cooling arrangements structurally associated with electric incandescent lamps H01K1/58; cooling arrangements structurally associated with light-emitting diodes H01L33/64
• CPC Class Codes: F21V 29/506 of globes, bowls or cover glasses
• CPC Class Codes: F21V 29/58 characterised by the coolants
• CPC Class Codes: F21V 29/83 the elements having apertures, ducts or channels, e.g. heat radiation holes
• CPC Class Codes: F21V 3/02 characterised by the shape
• CPC Class Codes: Y10S 977/774 Exhibiting three-dimensional carrier confinement, e.g. quantum dots

Abstract

A liquid-cooled LED bulb including a base and a shell connected to the base forming an enclosed volume. The liquid-cooled LED bulb also includes a plurality of LEDs attached to the base and disposed within the shell. The LED bulb also includes a thermally-conductive liquid held within the enclosed volume and a quantum dot material for adjusting the wavelength of light emitted from LED bulb.

Claims

1. A liquid-cooled light-emitting diode (LED) bulb comprising:

a base;

a shell connected to the base forming an enclosed volume;

a plurality of LEDs attached to the base and disposed within the shell;

a thermally-conductive liquid held within the enclosed volume; and

a ring structure including a quantum dot material for adjusting the wavelength of light emitted from LED bulb, wherein the ring structure is configured to facilitate a flow of the thermally conductive liquid from the LED mount to an inner surface of the shell, wherein an inside radius of the ring structure is spaced apart from a light-emitting face of at least one of the plurality of LEDs, and wherein an outside radius of the ring structure is spaced apart from the inner surface of the shell.

2. The liquid-cooled LED bulb of claim 1, wherein the flow of thermally conductive liquid is caused, at least in part, by natural convection.

3. The liquid-cooled LED bulb of claim 1, wherein the quantum dot material comprises quantum dot crystals having sizes ranging between from 2 to 10 nanometers in diameter.

4. The liquid-cooled LED bulb of claim 1, wherein the ring structure including the quantum dot material is configured to absorb light emitted from the LEDs having a first correlated color temperature (CCT) value to produce an emitted light having an emitted CCT value that is at least 1000°

K. lower than the first CCT value.

5. The liquid-cooled LED bulb of claim 1, wherein the ring structure including the quantum dot material is configured to absorb light emitted from the LEDs having a first correlated color temperature (CCT) value to produce an emitted light having an emitted CCT value that is at least 5000°

K. lower than the first CCT value.

6. The liquid-cooled LED bulb of claim 1, wherein the ring structure is a hollow toroid surrounding the plurality of LEDs and the quantum dot material is disposed on an interior surface of the ring structure.

7. The liquid-cooled LED bulb of claim 1, wherein the ring structure is a solid toroid surrounding the plurality of LEDs and the quantum dot material is dispersed in the solid volume of the ring structure.

8. The liquid-cooled LED bulb of claim 1, wherein the ring structure is a solid toroid surrounding the plurality of LEDs and the quantum dot material is disposed on an exterior surface of the ring structure.

9. A liquid-cooled light-emitting diode (LED) bulb comprising:

a base;

a shell connected to the base forming an enclosed volume;

a plurality of LEDs attached to the base and disposed within the shell;

a thermally-conductive liquid held within the enclosed volume; and

a ring structure including a quantum dot material and one or more phosphor materials for adjusting the wavelength of light emitted from LED bulb, wherein the ring structure is configured to facilitate a flow of the thermally conductive liquid from the LED mount to an inner surface of the shell, wherein an inside radius of the ring structure is spaced apart from a light-emitting face of at least one of the plurality of LEDs, and wherein an outside radius of the ring structure is spaced apart from the inner surface of the shell.

10. The liquid-cooled LED bulb of claim 9, wherein the quantum dot material and one or more phosphor materials produce light having a correlated color temperature (CCT) value lower than 3000°

K. and color rendering index (CRI) value greater than 90.

11. The liquid-cooled LED bulb of claim 9, wherein the thermally conductive liquid is able to facilitate natural convective cooling for the LEDs.

12. The liquid-cooled LED bulb of claim 9, wherein the quantum dot material comprises quantum dot crystals having sizes ranging between from 2 to 10 nanometers in diameter.

13. The liquid-cooled LED bulb of claim 9, wherein the quantum dot material is configured to absorb light emitted from the LEDs at substantially near 450 nm and emit light from the quantum dot material at a wavelength substantially longer than 450 nm.

14. The liquid-cooled LED bulb of claim 9, wherein the quantum dot material is configured to absorb light emitted from the LEDs having a first correlated color temperature (CCT) value to produce an emitted light having an emitted CCT value that is at least 1000°

K. lower than the first CCT value.

15. The liquid-cooled LED bulb of claim 9, wherein the quantum dot material is configured to absorb light emitted from the LEDs having a first correlated color temperature (CCT) value to produce an emitted light having an emitted CCT value that is at least 5000°

K. lower than the first CCT value.