Light emitting diode lighting system

• US 8,538,217 B2
• Filed: 03/17/2010
• Issued: 09/17/2013
• Est. Priority Date: 02/12/2007
• Status: Expired due to Fees

• Current Assignee: Intematix Corporation
• Original Assignee: Intematix Corporation
• Inventors: Li, Yi-Qun
• Primary Examiner(s): Sanghavi, Hemang
• Application Number:
  US12/726,201
• Publication Number:
  US 20100188867A1
• Time in Patent Office: 1,280 Days
• Field of Search: None
• US Class Current: 385/120
• CPC Class Codes: A61B 1/0653 with wavelength conversion
• CPC Class Codes: A61B 5/0084 for introduction into the body, e.g. by catheters A61B5/1459 takes precedence
• CPC Class Codes: A61B 5/4547 Evaluating teeth
• CPC Class Codes: F21S 6/002 Table lamps, e.g. for ambient lighting
• CPC Class Codes: F21S 8/02 of recess-mounted type, e.g. downlighters specially adapted for vehicle exteriors F21S41/00-F21S45/00
• CPC Class Codes: F21S 8/033 the surface being a wall or like vertical structure, e.g. building facade
• CPC Class Codes: F21S 8/04 intended only for mounting on a ceiling or the like overhead structures F21S8/02 takes precedence; details of ceiling bases F21V21/03
• CPC Class Codes: F21S 8/06 by suspension
• CPC Class Codes: F21V 14/06 by movement of refractors in vehicle head lamps F21S41/635
• CPC Class Codes: F21Y 2105/00 Planar light sources
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: G02B 6/0008 the light being emitted at the end of the fibre
• CPC Class Codes: G02B 6/0021 for housing at least a part of the light source, e.g. by forming holes or recesses
• CPC Class Codes: G02B 6/005 provided by one optical element, or plurality thereof, placed on the light output side of the light guide

Abstract

A lighting system for generating an illumination product comprises an excitation source, blue/UV LED, operable to generate excitation radiation and a remotely located phosphor, photo luminescent material. Excitation radiation is guided from the excitation source to the phosphor by a waveguiding medium, the waveguiding medium being configured such that the distance the radiation travels from the excitation source to the phosphor layer is at least one centimeter in length. The UV/blue excitation source provides excitation radiation to the phosphor(s), causing the phosphor(s) to photo luminesce, and it may also provide a component of the final illumination product. The configuration of the waveguide allows a greater flexibility in lighting system configurations, such as hanging lighting fixtures, desk lighting fixtures, floor standing lighting fixtures, desk lamps, track lighting, spot lighting, accent lighting, lighting panels, inspection lamps and endoscopes.

Claims

1. A lighting system comprising:

a light emitting flexible sheet that comprises a plurality of flexible elongate light transmissive waveguides, each said flexible waveguide having a light emitting surface;

at least one phosphor provided over at least a part of the light emitting surface of said flexible waveguide and

a plurality of light emitting diodes, each said light emitting diode operable to generate blue excitation light having a peak emission wavelength greater than 450 nm,

the lighting system being configured such that excitation light is coupled into the waveguides such that said excitation light propagates through said flexible waveguide and is then emitted through the light emitting surface and wherein at least a part of the excitation radiation excites the at least one phosphor which emits light of a different color, wherein the illumination product of the system is a combination of the excitation light and photo luminescent light emitted by the at least one phosphor.

2. The lighting system of claim 1, and further comprising a further light transmissive waveguide in optical communication with at least one end of each flexible waveguide and wherein excitation light is coupled into the further waveguide and is then coupled into each of the flexible waveguides.

3. The lighting system of claim 2, wherein the further waveguide is flexible.

4. The lighting system of claim 2 or claim 3, and further comprising a plurality apertures in at least one edge of the further waveguide and wherein each light emitting diode is mounted in a respective one of the apertures.

5. The lighting system of claim 1, wherein the at least one phosphor is provided as a layer on at least a part of the light emitting surface of each flexible waveguide.

6. The lighting system of claim 1, wherein the at least one phosphor is a composition of at least two phosphors.

7. The lighting system of claim 1, wherein the flexible waveguides comprise optical fibers.

8. The lighting system of claim 7, wherein the optical fibers have a cross section selected from the group consisting of:

circular, elliptical and square.

9. The lighting system of claim 7, wherein the optical fibers are woven as a flexible sheet and comprise the warp and/or weft of the sheet.

10. The lighting system of claim 7, wherein the plurality of optical fibers are mounted on a flexible backing material.

11. The lighting system of claim 1, and further comprising a surface topology of the light emitting surface of the flexible waveguides, said topology being configured to enhance emission of light from the light emitting surface.

12. The lighting system of claim 11, wherein the surface topology is selected from the group consisting of:

a surface roughening and a regular patterning.

13. The lighting system of claim 1, wherein the flexible waveguide is a medium selected from the group consisting of:

a polymeric resin, an acrylic, a butyrate and a glass.

14. The lighting system of claim 1, wherein the peak emission wavelength of at least one component of the photo luminescent light emitted by the at least one phosphor is greater than about 500 nm.

15. The lighting system of claim 1, wherein the lighting system produces a white light illumination product.

16. The lighting system of claim 10, wherein the optical fibers are arranged in a pattern on the flexible backing material.