LED lighting devices with quantum dot glass containment plates

• US 9,202,996 B2
• Filed: 03/14/2013
• Issued: 12/01/2015
• Est. Priority Date: 11/30/2012
• Status: Expired due to Fees

• Current Assignee: Corning Incorporated
• Original Assignee: Corning Incorporated
• Inventors: Orsley, Timothy James, Trutna, William Richard
• Primary Examiner(s): Wilczewski, Mary
• Assistant Examiner(s): CHIU, TSZ K
• Application Number:
  US13/828,169
• Publication Number:
  US 20140151729A1
• Time in Patent Office: 992 Days
• Field of Search: 257/13, 257/88, 257/89, 257/E33.005, 257/E33.06, 257/E33.067
• US Class Current: 1/1
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2924/00012 Relevant to the scope of the group, the symbol of which is combined with the symbol of this group
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/181 Encapsulation
• CPC Class Codes: H01L 33/504 Elements with two or more wavelength conversion materials
• CPC Class Codes: H01L 33/505 characterised by the shape, e.g. plate or foil

Abstract

A lighting device is provided comprising a chip-on-board (COB) light emitting diode (LED) light source, a light source encapsulant, a quantum dot distributed color conversion medium, and a quantum dot glass containment plate. The COB LED light source comprises at least one LED and defines a light source encapsulant cavity in which the light source encapsulant is distributed over the LED. The quantum dot glass containment plate is positioned over the light source encapsulant cavity and contains a quantum dot distributed color conversion medium. The distributed color conversion medium comprises a quantum dot structure and is distributed in two dimensions over an emission field of the lighting device within the quantum dot glass containment plate.

Claims

1. A lighting device comprising a chip-on-board (COB) light emitting diode (LED) light source, a light source encapsulant, a quantum dot distributed color conversion medium, and a quantum dot glass containment plate, wherein:

the COB LED light source comprises at least one LED and defines a light source encapsulant cavity in which the light source encapsulant is distributed over the LED;

the quantum dot glass containment plate is positioned over the light source encapsulant cavity and contains the distributed color conversion medium; and

the distributed color conversion medium comprises a quantum dot structure and is distributed in two dimensions over an emission field of the lighting device within the quantum dot glass containment plate;

the light source encapsulant comprises a primary distributed color conversion medium;

the color conversion medium of the quantum dot glass containment plate defines a supplemental emission field of the lighting device; and

the emission field defined by the primary distributed color conversion medium is spatially congruent with, but spectrally distinct from, the supplemental emission field defined by the quantum dot glass containment plate.

2. The lighting device of claim 1, wherein:

the quantum dot glass containment plate comprises a glass frame; and

the quantum dot structure is contained within an interior volume of the glass frame.

3. The lighting device of claim 1, wherein:

the quantum dot glass containment plate comprises opposing glass panels that are sealed at complementary edges to define an interior volume; and

the quantum dot structure is contained within the interior volume of the quantum dot glass containment plate.

4. The lighting device of claim 1, wherein the quantum dot glass containment plate comprises a variety of quantum dot sizes that are blended to obtain a particular color.

5. The lighting device of claim 1, wherein:

the light source encapsulant comprises silicone; and

the primary distributed color conversion medium comprises phosphor.

6. The lighting device of claim 1, wherein an emission spectrum of the emission field defined by the quantum dot glass containment plate adds optical warmth to an emission spectrum of the emission field defined by the primary distributed phosphor color conversion medium of the light source encapsulant.

7. A lighting device comprising a chip-on-board (COB) light emitting diode (LED) light source, a light source encapsulant, a quantum dot distributed color conversion medium, and a quantum dot glass containment plate, wherein:

the COB LED light source comprises at least one LED and defines a light source encapsulant cavity in which the light source encapsulant is distributed over the LED;

the quantum dot glass containment plate is positioned over the light source encapsulant cavity and contains the distributed color conversion medium; and

the distributed color conversion medium comprises a quantum dot structure and is distributed in two dimensions over an emission field of the lighting device within the quantum dot glass containment plate;

the lighting device comprises a primary glass containment plate comprising a primary distributed color conversion medium;

the color conversion medium of the quantum dot glass containment plate defines a supplemental emission field of the lighting device; and

the emission field defined by the distributed color conversion medium is spatially congruent with, but spectrally distinct from, the supplemental emission field defined by the quantum dot plate.

8. The lighting device of claim 7, wherein:

the primary glass containment plate comprises a glass matrix; and

the primary distributed color conversion medium comprises a phosphor distributed in the glass matrix.

9. The lighting device of claim 7, wherein:

the glass containment plate comprises a glass frame; and

the primary distributed color conversion medium comprises a quantum dot structure contained within an interior volume of the glass frame.

10. The lighting device of claim 7, wherein:

the primary distributed color conversion medium comprises a quantum dot structure;

the primary glass containment plate comprises opposing glass panels that are sealed at complementary edges to define an interior volume; and

the quantum dot structure is contained within the interior volume of the primary glass containment plate.

11. The lighting device of claim 7, wherein a bonding layer is provided between the primary glass containment plate and the quantum dot glass containment plate to permit separate manufacture and subsequent bonding of the primary glass containment plate and the quantum dot glass containment plate.

12. The lighting device of claim 7, wherein the primary glass containment plate comprises a variety of quantum dot sizes that are blended to obtain a particular color.

13. A lighting device comprising a chip-on-board (COB) light emitting diode (LED) light source, a light source encapsulant, a quantum dot distributed color conversion medium, and a quantum dot glass containment plate, wherein:

the COB LED light source comprises at least one LED and defines a light source encapsulant cavity in which the light source encapsulant is distributed over the LED;

the quantum dot glass containment plate is positioned over the light source encapsulant cavity and contains the distributed color conversion medium; and

the distributed color conversion medium comprises a quantum dot structure and is distributed in two dimensions over an emission field of the lighting device within the quantum dot glass containment plate;

the COB LED light source comprises a thermal heat sink framework;

the light source encapsulant is free of any distributed color conversion medium;

the light source encapsulant comprises silicone;

the quantum dot glass containment plate is positioned over the light source encapsulant cavity;

the light source encapsulant is distributed over the LED at a thickness that is sufficient to encapsulate the LED and define encapsulant thermal conduction paths T_PE extending through the light source encapsulant to the thermal heat sink framework from the distributed color conversion medium of the quantum dot glass containment plate; and

the thickness of the light source encapsulant is such that the thermal conduction paths T_PE extend less than approximately 100 μ

m through the light source encapsulant.

14. The lighting device of claim 13, wherein the thickness of the light source encapsulant is such that the thermal conduction paths T_PE extend less than approximately 50 μ

m through the light source encapsulant.

15. The lighting device of claim 13, wherein the thickness of the light source encapsulant is such that the thermal conduction paths T_PE encounter a thermal resistance of less than approximately 15°

C./W through the light source encapsulant.

16. The lighting device of claim 13, wherein the thickness of the light source encapsulant is such that the thermal conduction paths T_PE encounter a thermal resistance of less than approximately 10°

C./W through the light source encapsulant.