LED signal lamp

• US 20080218993A1
• Filed: 09/28/2007
• Published: 09/11/2008
• Est. Priority Date: 03/05/2007
• Status: Active Grant

• Current Assignee: BX LED LLC (Ni, Wang & Massand, PLLC)
• Original Assignee: Intematix Corporation
• Inventors: Li, Yi-Qun
• Granted Patent: US 7,883,226 B2
• Time in Patent Office: Days
• US Class Current: 362/84
• CPC Class Codes: B61L 2207/02 using light-emitting diodes [LEDs]
• CPC Class Codes: B61L 5/1827 using light sources of different colours and a common optical system
• CPC Class Codes: B61L 5/1854 Mounting and focussing of the light source in a lamp, fixing means
• CPC Class Codes: F21V 13/14 the elements being filters or photoluminescent elements, reflectors and refractors
• CPC Class Codes: F21V 3/049 Patterns or structured surfaces for diffusing light, e.g. frosted surfaces
• CPC Class Codes: F21V 5/008 Combination of two or more successive refractors along an optical axis
• CPC Class Codes: F21V 5/10 comprising photoluminescent material
• CPC Class Codes: F21V 9/08 for producing coloured light, e.g. monochromatic; for reducing intensity of light with provision for controlling the colour F21V9/40
• CPC Class Codes: F21V 9/32 characterised by the arrangement of the photoluminescent material
• CPC Class Codes: F21W 2111/02 for roads, paths or the like
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: G08G 1/095 Traffic lights
• CPC Class Codes: G09F 13/04 Signs, boards or panels, illuminated from behind the insignia
• CPC Class Codes: Y10S 362/80 Light emitting diode

Abstract

An LED signal lamp (100) comprises: a housing (102), at least one LED excitation source (108) operable to emit excitation radiation of a first wavelength range (blue light), at least one phosphor material (114) for converting at least a part of the excitation radiation to radiation of a second wavelength range and a substantially transparent cover (104) provided on the housing opening. In one arrangement the excitation source (LED chip) incorporates the phosphor material. Alternatively, the phosphor can be provided remote to the excitation source such as for example on a transparent substrate which is disposed between the excitation source and transparent cover. In other arrangements, the phosphor is provided on the transparent cover or other optical components as a layer on a surface of the cover or incorporated within the cover/optical component material.

Claims

1. An LED signal lamp comprising:

a housing, at least one LED excitation source operable to emit excitation radiation of a first wavelength range, at least one phosphor material for converting at least a part of the excitation radiation to radiation of a second wavelength range and a substantially transparent cover provided on the housing opening.

2. The signal lamp according to claim 1, wherein the at least one LED excitation source incorporates the at least one phosphor material.

3. The signal lamp according to claim 1, wherein the at least one phosphor material is provided remote to the at least one LED excitation source.

4. The signal lamp according to claim 3, wherein the phosphor is disposed between the at least one LED excitation source and the transparent cover.

5. The signal lamp according to claim 4, wherein the phosphor is provided on a transparent substrate which is disposed between the excitation source and the transparent cover.

6. The signal lamp according to claim 5, wherein the phosphor is provided as a layer on a surface of the transparent substrate.

7. The signal lamp according to claim 5, wherein the phosphor is incorporated in the substrate material.

8. The signal lamp according to claim 3, wherein the phosphor is provided on the transparent cover.

9. The signal lamp according to claim 8, wherein the phosphor is provided as a layer on a surface of the cover.

10. The signal lamp according to claim 9, wherein the phosphor defines a device or symbol.

11. The signal lamp according to claim 8, wherein the phosphor is incorporated in the cover material.

12. The signal lamp according to claim 1, and further comprising an optical condenser for focusing light emitted by the lamp.

13. The signal lamp according to claim 11, wherein the optical condenser comprises a lens structure formed on a surface of the transparent cover.

14. The signal lamp according to claim 12, and further comprising an optical element disposed between the phosphor and cover, the optical element configured in conjunction with the lens structure to direct light in a desired direction or pattern.

15. The signal lamp according to claim 1, wherein the at least one LED excitation source comprises a blue/UV emitting LED.

16. The signal lamp according to claim 15, wherein the lamp is configured to generate light selected from the group consisting of:

red light, orange light, amber light, green light, white light and blue light.

17. The signal lamp according to claim 1, wherein the phosphor is selected from the group consisting of:

a silicate-based phosphors of general composition A₃Si(O,D)₅ and A₂Si(O,D)₄ where A=Sr, Ba, Mg or Ca and D=Cl, Fl, N or S;

an aluminate-based phosphor;

a nitride phosphor;

a sulfate phosphor;

an oxy-nitride phosphor;

an oxy-sulfate phosphor and a garnet material (YAG).

18. The signal lamp according to claim 1 and selected from the group consisting of a vehicle traffic signal, a pedestrian traffic signal, a railway traffic signal, an aeronautical ground light and aviation ground light.