LIGHT EMITTING DIODE (LED) BASED LIGHTING SYSTEMS

• US 20110188228A1
• Filed: 04/12/2011
• Published: 08/04/2011
• Est. Priority Date: 03/05/2007
• Status: Active Grant

• Current Assignee: Intematix Corporation
• Original Assignee: Intematix Corporation
• Inventors: Li, Yi-Qun
• Granted Patent: US 8,376,580 B2
• Time in Patent Office: Days
• US Class Current: 362/84
• CPC Class Codes: F21S 8/033 the surface being a wall or like vertical structure, e.g. building facade
• CPC Class Codes: F21S 8/06 by suspension
• CPC Class Codes: F21S 9/037 the solar unit and the lighting unit being located within or on the same housing
• CPC Class Codes: F21V 1/00 Shades for light sources , i.e. lampshades for table, floor, wall or ceiling lamps
• CPC Class Codes: F21V 1/17 the material comprising photoluminescent substances
• CPC Class Codes: F21V 13/08 the elements being filters or photoluminescent elements and reflectors
• CPC Class Codes: F21V 21/0824 Ground spikes
• CPC Class Codes: F21V 3/08 the material comprising photoluminescent substances
• CPC Class Codes: F21V 3/12 the coatings comprising photoluminescent substances
• CPC Class Codes: F21V 9/32 characterised by the arrangement of the photoluminescent material
• CPC Class Codes: F21W 2131/103 of streets or roads
• CPC Class Codes: F21Y 2105/10 comprising a two-dimensional array of point-like light-generating elements
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: Y02B 20/72 in street lighting
• CPC Class Codes: Y10S 362/80 Light emitting diode

Abstract

A lighting system comprises at least one excitation source (5), preferably an LED, operable to generate and radiate excitation radiation of a first wavelength (λ₁); a shade (4) configured to at least in part surround the at least one source (5) and remotely located thereto; and at least one phosphor (16) provided in or on at least a part of the shade (4), wherein the phosphor (16) emits radiation of a different wavelength in response to incident excitation radiation. The phosphor can be provided on a part of an outer or inner surface of the shade. Alternatively, or in addition, the phosphor is incorporated within the shade. The lighting system finds particular application as a hanging, a desk, a floor standing, a wall mountable, a spot, an outdoor or an accent lighting fixture.

Claims

1. A lighting system comprising:

at least one blue emitting LED configured to emit blue excitation light having a wavelength ranging from 420 nm to 470 nm;

a shade located remotely to the at least one LED and configured to at least in part surround the LED to thereby prevent at least in part direct viewing of the at least one LED, wherein the shade is configured such that blue excitation light travels in free-space a distance of at least one centimeter from the at least one LED to the shade; and

a first phosphor provided as a layer on at least a part of an inner and/or outer surface of the shade;

wherein the phosphor emits light of a different wavelength in response to incident excitation light, and wherein the combined light from the LED and the phosphor generate a desired color of light.

2. The lighting system of claim 1, and further comprising a second phosphor selected from the group consisting of:

being provided as a respective layer and being provided as a mixture with the first phosphor.

3. The lighting system of claim 1, wherein the shade is selected from the group consisting of being:

a circular disc, a hollow cylinder, a spherical shell, polygonal, multifaceted and paraboloidal in form.

4. The lighting system of claim 1, wherein the shade further comprises a surface topology to aid coupling of excitation light into the shade.

5. The lighting system of claim 4, wherein the surface topology is selected from the group consisting of:

grooves, ribs and a surface roughening.

6. The lighting system of claim 1, wherein light emitted from an opening in the shade is of a first color and light emitted through the shade is of a second different color.

7. The lighting system of claim 6, wherein the light emitted from the opening in the shade appears white in color.

8. The lighting system of claim 1, and further comprising a reflector configured to direct excitation light towards the shade.

9. The lighting system of claim 1, wherein the shade is selected from the group consisting of being:

translucent, transparent and opaque.

10. A lighting system comprising:

at least one blue emitting LED configured to emit blue excitation light having a wavelength ranging from 420 nm to 470 nm;

a shade located remotely to the at least one LED and configured to at least in part surround the LED to thereby prevent at least in part direct viewing of the at least one LED, wherein the shade is configured such that blue excitation light travels in free-space a distance of at least one centimeter from the at least one LED to the shade; and

a first phosphor incorporated in and dispersed throughout the shade;

wherein the phosphor emits light of a different wavelength in response to incident excitation light, and wherein the combined light from the LED and the phosphor generate a desired color of light that appears white in color to the eye.

11. The lighting system of claim 10, and further comprising a second phosphor wherein the second phosphor is provided as a mixture with the first phosphor and the mixture incorporated in the shade.

12. The lighting system of claim 10, wherein the shade is selected from the group consisting of being:

a circular disc, a hollow cylinder, a spherical shell, polygonal, multifaceted and paraboloidal in form.

13. The lighting system of claim 10, wherein the shade further comprises a surface topology to aid coupling of excitation light into the shade.

14. The lighting system of claim 13, wherein the surface topology is selected from the group consisting of:

grooves, ribs and a surface roughening.

15. The lighting system of claim 10, wherein light emitted from an opening in the shade is of a first color and light emitted through the shade is of a second different color.

16. The lighting system of claim 15, wherein the light emitted from the opening in the shade appears white in color.

17. The lighting system of claim 10, and further comprising a reflector configured to direct excitation light towards the shade.

18. The lighting system of claim 10, wherein the shade is selected from the group consisting of being:

translucent, transparent and opaque.

19. A lighting system comprising:

a housing having an opening;

at least one blue emitting LED housed in the housing and configured to emit blue excitation light having a wavelength ranging from 420 nm to 470 nm;

a shade covering the housing opening such that light emitted by the system is emitted through the shade, the shade being configured such that blue excitation light travels in free-space a distance of at least one centimeter from the at least one LED to the shade; and

a first phosphor that emits light of a different wavelength in response to incident excitation light, wherein the combined light from the LED and the phosphor generate a desired color of light that appears white in color to the eye; and

wherein the first phosphor is selected from the group consisting of being;

provided as a layer on at least a part of an inner surface of the shade;

provided as a layer on an outer surface of the shade; and

incorporated in and dispersed throughout the shade.

20. The lighting system of claim 19, wherein the shade comprises a substantially circular disc.

21. The lighting system of claim 19, and further comprising a second phosphor selected from the group consisting of:

being provided as a respective layer and being provided as a mixture with the first phosphor.

22. The lighting system of claim 19, wherein the shade further comprises a surface topology to aid coupling of excitation light into the shade.

23. The lighting system of claim 22, wherein the surface topology is selected from the group consisting of:

grooves, ribs and a surface roughening.