LED Fresnel lighting system including active cooling

• US 8,882,283 B2
• Filed: 03/15/2011
• Issued: 11/11/2014
• Est. Priority Date: 03/15/2010
• Status: Active Grant

• Current Assignee: Litepanels Limited (Vitec Group PLC)
• Original Assignee: Litepanels Limited (Vitec Group PLC)
• Inventors: Baxter, Kevin C., Holmes, Fred H., Fisher, Ken
• Primary Examiner(s): Mai, Anh
• Assistant Examiner(s): FEATHERLY, HANA SANEI
• Application Number:
  US13/048,847
• Publication Number:
  US 20120063116A1
• Time in Patent Office: 1,337 Days
• Field of Search: 362/6
• US Class Current: 362/6
• CPC Class Codes: F21V 14/06 by movement of refractors in vehicle head lamps F21S41/635
• CPC Class Codes: F21V 29/51 using condensation or evaporation of a fluid, e.g. heat pipes
• CPC Class Codes: F21V 29/54 using thermoelectric means, e.g. Peltier elements
• CPC Class Codes: F21V 29/56 using liquid coolants F21V29/51 takes precedence
• CPC Class Codes: F21V 29/673 the fans being used for intake
• CPC Class Codes: F21V 29/677 the fans being used for discharging
• CPC Class Codes: F21V 29/70 characterised by passive heat-dissipating elements, e.g. heat-sinks
• CPC Class Codes: F21V 29/71 using a combination of separate elements interconnected by heat-conducting means, e.g. with heat pipes or thermally conductive bars between separate heat-sink elements
• CPC Class Codes: F21V 29/74 with fins or blades
• CPC Class Codes: F21V 29/76 with essentially identical parallel planar fins or blades, e.g. with comb-like cross-section
• CPC Class Codes: F21V 5/045 the lens having discontinuous faces, e.g. Fresnel lenses
• CPC Class Codes: F21W 2131/406 for theatres, stages or film studios
• 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: G03B 15/05 Combinations of cameras with electronic flash apparatus; Electronic flash units
• CPC Class Codes: G03B 21/16 Cooling; Preventing overheating

Abstract

A lighting apparatus for film, television, video capture, motion picture and photography which includes a Fresnel lens fixed in a housing which contains a tight array of high power LEDs. The LED panel or board is mated to a heat dissipating apparatus to provide active cooling and together forming an LED engine. The LED engine is mounted to a slider allowing the LED engine to be adjusted within the housing with respect to the lens. Light shaping diffusion may be included on the housing. A power supply unit may also be included in the housing. When in electrical communication, the LED engine and power supply unit function as an integrated self-contained lighting apparatus. Optionally, the power supply may have an integrated dimmer switch, and may be capable of receiving PFC power or have an integrated battery unit.

Claims

1. A lighting system suitable for image capture, comprising:

a housing;

an LED engine supported in said housing;

said LED engine including a fan for forcing air past said LED engine;

a Fresnel lens supported by the housing wherein at least a portion of light emitted by said LED engine passes through said Fresnel lens to create a beam and wherein said Fresnel lens is movable with respect to said LED engine to effect adjustment of said beam; and

a control input for selectively controlling an illumination level of said emitted light.

2. The lighting system of claim 1 wherein said LED engine includes at least one high power LED.

3. The lighting system of claim 1 wherein said Fresnel lens is affixed to said housing and said LED engine is capable of movement with respect to said housing.

4. The lighting system of claim 1 wherein said Fresnel lens is plastic.

5. The lighting system of claim 1 wherein said LED engine includes an array of high power LEDs.

6. The lighting system of claim 5 wherein said LED engine includes a first array of LEDs emitting light at a first color temperature and a second array of LEDs emitting light at a second color temperature.

7. The lighting system of claim 5 wherein said LED engine includes an array of phosphor based LEDs.

8. The lighting system of claim 7 wherein said phosphor based LEDs are high power LEDs.

9. The lighting system of claim 1 wherein said fan produces a laminar flow of air past said LED engine.

10. The lighting system of claim 1 wherein said LED engine includes a heat sink such that said fan forces air across said heat sink.

11. The lighting system of claim 10 wherein said heat sink includes a plurality of fins such that said fan forces air across said plurality of fins.

12. The lighting system of claim 10 wherein said LED engine includes at least one heat pipe for active cooling.

13. The lighting system of claim 12 wherein said at least one heat pipe contains a liquid therein.

14. The lighting system of claim 13 wherein said LED engine includes at least one pump for pumping said liquid through said at least one heat pipe.

15. The lighting system of claim 13 wherein said at least one heat pipe is sealed.

16. The lighting system of claim 15 wherein said at least one heat pipe includes at least one upward extending arm.

17. The lighting system of claim 16 wherein said at least one upward extending arm includes a plurality of fins thereon.

18. The lighting system of claim 17 wherein said LED engine includes a plurality of heat pipes.

19. The lighting system of claim 1 further including a control input for selectively controlling the movement of either said Fresnel lens with respect to said LED engine or said LED engine with respect to said Fresnel lens.

20. The lighting system of claim 1 wherein said fan operates at a speed, a tachometer for measuring said speed and further including a control input for selectively controlling the speed of said fan.

21. The lighting system of claim 20 wherein said control inputs may be controlled remotely.

22. The lighting system of claim 21 wherein said remote control operation is performed via the Internet.

23. The lighting system of claim 21 wherein said remote control operation is performed via WiFi.

24. The lighting system of claim 21 wherein said remote control operation is performed via TCP/IP.

25. The lighting system of claim 21 wherein said remote control operation is performed via a DMX.

26. The lighting system of claim 1 further including a lens for providing light shaping diffusion to said light emitted from said LED engine.