Light emitting diode-based signal light

• US 6,796,698 B2
• Filed: 04/01/2002
• Issued: 09/28/2004
• Est. Priority Date: 04/01/2002
• Status: Expired due to Term

• Current Assignee: Current Lighting Solutions, LLC (f/k/a GE Lighting Solutions, LLC) (American Industrial Partners)
• Original Assignee: Gelcore (General Electric Company)
• Inventors: Sommers, Mathew, Martineau, Patrick
• Primary Examiner(s): Sember, Thomas M.
• Assistant Examiner(s): Sawhney, Hargobind S.
• Application Number:
  US10/063,224
• Publication Number:
  US 20030185005A1
• Time in Patent Office: 911 Days
• Field of Search: 362/339, 362/340, 362/303, 362/298, 362/302, 362/305, 362/240, 362/255, 362/256, 362/800, 362/236, 362/293, 362/307, 362/331, 362/226, 362/241, 362/245, 362/247, 362/327, 362/335, 362/338, 340/907, 340/815.45, 340/815.67, 340/641, 340/642, 313/500, 313/511, 313/512, 313/113, 313/114, 116/63.R
• US Class Current: 362/555
• CPC Class Codes: F21K 9/23 Retrofit light sources for lighting devices with a single fitting for each light source, e.g. for substitution of incandescent lamps with bayonet or threaded fittings
• CPC Class Codes: F21V 29/70 characterised by passive heat-dissipating elements, e.g. heat-sinks
• CPC Class Codes: F21V 7/0008 providing for indirect lighting
• CPC Class Codes: F21V 7/041 with conical or pyramidal surface
• CPC Class Codes: F21W 2111/00 Use or application of lighting devices or systems for signalling, marking or indicating, not provided for in codes F21W2102/00 – F21W2107/00
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: G08G 1/095 Traffic lights
• CPC Class Codes: Y10S 362/80 Light emitting diode

Abstract

A light-emitting diode-based light source (40) for retro-fitting into a traffic signal lamp (10) employing an incandescent light bulb (12) includes at least one light emitting diode (LED) (46), a dispersing reflector (62) cooperating with the at least one LED (46) to adapt light (60) produced by the at least one LED (46) for receipt by optics of the traffic signal lamp (10), and a screw-type electrical connector (42) adapted to mate with a threaded socket connector (18) of the traffic signal lamp (10). The screw-type electrical connector (42) is adapted to transmit electrical power to the at least one LED (46). A method (100) is provided for the retro-fitting, including the step (104) of removing the threaded light bulb (12) from the threaded socket (18), and the step (106) of connecting the threaded LED light source (40) into the threaded socket (18).

Claims

1. A traffic signal ball producing a light output, the traffic signal ball comprising:

a lamp including;

a plurality of LEDs, an optical element arranged to disperse forwardly directed light produced by the LEDs, the optical element being partially reflective and partially transmissive, that portion of forwardly directed light passing through the optical element defining a direct light contribution to the light output, and

a threaded electrical connector, and

a collimating reflector defining a reflector focus, the optical element being disposed at about the reflector focus such that the dispersed light is substantially collimated by the collimating reflector to define a reflected light contribution to the light output.

2. The traffic signal ball as set forth in claim 1, wherein the collimating reflector includes:

a parabolic reflector arranged to receive and substantially collimate at least a portion of light dispersed by the optical element.

3. The traffic signal ball as set forth in claim 1, further including:

a lens arranged to receive light collimated by the collimating reflector.

4. The traffic signal ball as set forth in claim 1, further including:

one of a filter and a tinted lens for spectrally filtering the light light output.

5. The traffic signal ball as set forth in claim 1, wherein the collimating reflector is adapted to operate with an incandescent light bulb.

6. The traffic signal ball as set forth in claim 5, wherein a ratio of the light dispersed by the optical element to the direct light contribution is selected to correspond to light output of a filament of said incandescent light bulb.

7. The traffic signal ball as set forth in claim 1, wherein a ratio of the light dispersed by the optical element to the direct light contribution is selected to approximate one of a point light source and a line light source.

8. An LED-based light source comprising:

a threaded electrical connector arranged to receive electrical power;

power converting electronics that receive the electrical power and convert the electrical power to converted power;

a plurality of LEDs arranged to receive the converted power, the LEDs producing a generally forwardly directed first light beam responsive to receipt of the converted power,

a light dispersing element arranged at a focal region of a collimating reflector, the light dispersing element intercepting and transforming the first light beam into dispersed light emanating from the focal region; and

an optical system including the collimated reflector arranged to focus dispersed light emanating from the focal region into an output light beam having selected beam characteristics.

9. The LED-based light source as set forth in claim 8, wherein the collimating reflector is arranged to substantially collimate dispersed light emanating from the focal region, and the optical system further includes a lens arranged to receive the substantially collimated light.

10. The LED-based light source as set forth in claim 9, wherein the threaded electrical connector, the plurality of LEDs, the light dispersing element, the collimating reflector, and the lens comprise a unitary threadedly connectable light source.

11. The LED-based light source as set forth in claim 9, further including:

a heat sinking means for controlling heat generated by the light-emitting diode-based light source.

12. A lamp for use in a light producing apparatus having a socket through which power is supplied to the lamp, said socket holding the lamp, and a collimating reflector that directs light outwardly from the light producing apparatus, said lamp comprising:

a connector by which the lamp is installed in the socket;

a plurality of LEDs electrically connected to the connector; and

a partially light-transmissive and partially light-reflective redirection optical element arranged at about a focal position of the collimating reflector when the lamp connector is installed in the socket, the redirection optical element (i) partially reflecting light emitted from the plurality of LEDs into the collimating reflector and (ii) partially transmitting light emitted from the plurality of LEDs, wherein the partially reflected light and the partially transmitted light together approximate one of a point light source and a line light source.

13. The lamp as set forth in claim 12, wherein the connector is a threaded connector adapted to screw into the socket.

14. The lamp as set forth in claim 12, wherein the connector, the LEDs, and the redirection element are physically integrated into a single mechanically rigid apparatus.