Methods and apparatus for controlling a color temperature of lighting conditions

• US 7,520,634 B2
• Filed: 12/30/2005
• Issued: 04/21/2009
• Est. Priority Date: 12/17/1997
• Status: Expired due to Fees

• Current Assignee: Philips Lighting North America Corporation (Koninklijke Philips N.V.)
• Original Assignee: Philips Solid-State Lighting Solutions (Koninklijke Philips N.V.)
• Inventors: Lys, Ihor A., Mueller, George G., Dowling, Kevin J., Morgan, Frederick M., Ducharme, Alfred D.
• Primary Examiner(s): Lee; Y My Quach
• Application Number:
  US11/322,891
• Publication Number:
  US 20060109649A1
• Time in Patent Office: 1,208 Days
• Field of Search: 362/231, 362/251, 362/260, 362/263, 362/265, 362/276, 362/295, 362/394, 362/800
• US Class Current: 362/276
• CPC Class Codes: F21K 9/20 Light sources comprising attachment means
• CPC Class Codes: F21V 23/045 the sensor receiving a signal from a remote controller
• CPC Class Codes: F21V 23/0457 the sensor sensing the operating status of the lighting device, e.g. to detect failure of a light source or to provide feedback to the device
• CPC Class Codes: F21V 3/04 characterised by materials, surface treatments or coatings
• CPC Class Codes: F21W 2131/406 for theatres, stages or film studios
• CPC Class Codes: F21Y 2103/10 comprising a linear array of point-like light-generating elements
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: H05B 45/00 Circuit arrangements for operating light-emitting diodes [LED]
• CPC Class Codes: H05B 45/20 Controlling the colour of the light
• CPC Class Codes: H05B 45/22 using optical feedback
• CPC Class Codes: Y02B 20/30 Semiconductor lamps, e.g. solid state lamps [SSL] light emitting diodes [LED] or organic LED [OLED]
• CPC Class Codes: Y10S 362/80 Light emitting diode

Abstract

Methods and apparatus in which at least one first LED generates first radiation having a first spectrum, and at least one second LED generates second radiation having a second spectrum different than the first spectrum. One or more controllers control at least one of the first radiation and the second radiation so as to control at least a color temperature of visible radiation. In one example, one or more sensors monitor at least one characteristic of sample radiation and provide one or more sensor signals to the one or more controllers, which in turn control at least the color temperature of the visible radiation based at least in part on the at least one sensor signal. In various implementations, the sample radiation may be ambient illumination (e.g., natural-light and/or light from other light sources), may be the visible radiation itself (e.g., to provide feedback to the one or more controllers), or generally any desired lighting condition to simulate.

Claims

1. An apparatus, comprising:

at least one first LED to generate first radiation having a first spectrum;

at least one second LED to generate second radiation having a second spectrum different than the first spectrum;

at least one controller to control at least one of the first radiation and the second radiation so as to control at least a color temperature of visible radiation emanating from the apparatus; and

at least one sensor to monitor at least one characteristic of sample radiation and provide at least one sensor signal to the at least one controller, wherein;

the at least one controller is configured to control at least the color temperature of the visible radiation based at least in part on the at least one sensor signal;

the sample radiation includes at least one ambient illumination condition; and

the at least one controller is configured to control at least the color temperature of the visible radiation emanating from the apparatus based at least in part on the at least one ambient illumination condition.

2. The apparatus of claim 1, wherein the at least one first LED includes at least one first white LED.

3. The apparatus of claim 2, wherein the at least one second LED includes at least one second white LED.

4. The apparatus of claim 2, further comprising at least one user interface coupled to the at least one controller to permit a user to control the visible radiation.

5. The apparatus of claim 2, further comprising at least one housing to support at least the at least one first LED and the at least one second LED.

6. The apparatus of claim 5, wherein the at least one housing is configured to resemble a conventional light bulb.

7. The apparatus of claim 6, wherein the at least one housing is configured to resemble one of an incandescent light bulb, a fluorescent light bulb, and a halogen light bulb.

8. The apparatus of claim 6, wherein the housing comprises at least one connector that is adapted to engage mechanically and electrically with a conventional light socket arrangement.

9. The apparatus of claim 8, wherein the at least one connector is adapted to engage mechanically and electrically with one of an incandescent light socket arrangement, a fluorescent light socket arrangement, and a halogen light socket arrangement.

10. The apparatus of claim 1, wherein the at least one sensor is configured to wirelessly communicate the at least one sensor signal to the at least one controller.

11. The apparatus of claim 1, wherein the at least one sensor is configured to communicate the at least one sensor signal to the at least one controller and at least one other device that is responsive to the at least one sensor signal.

12. The apparatus of claim 1, wherein the at least one sensor includes at least one of a photodiode, a phototransistor, a photomultiplier, a channel-plate intensifier, a charge-coupled device, and an intensified silicon intensifier target (ISIT).

13. The apparatus of claim 1, wherein the at least one sensor includes at least one of a colorimeter, a photometer and a radiometer.

14. The apparatus of claim 1, wherein the at least one sensor includes a camera.

15. The apparatus of claim 1, wherein the at least one characteristic includes at least an intensity of the sample radiation.

16. The apparatus of claim 1, wherein the at least one characteristic includes at least one spectral property of the sample radiation.

17. The apparatus of claim 1, wherein the at least one characteristic includes at least a color temperature of the sample radiation.

18. The apparatus of claim 17, wherein the at least one characteristic includes the color temperature and an intensity of the sample radiation.

19. The apparatus of claim 1, wherein the at least one ambient illumination condition includes at least one external natural-light ambient illumination condition.

20. The apparatus of claim 1, wherein the at least one ambient illumination condition exists in an environment in which the apparatus is disposed.

21. The apparatus of claim 1, wherein the at least one ambient illumination condition exists in an environment other than that in which the apparatus is disposed.

22. The apparatus of claim 1, wherein:

the at least one ambient illumination condition includes at least two different ambient illumination conditions; and

the at least one controller is configured to control a first intensity of the first radiation and a second intensity of the second radiation so as to provide at least two different color temperatures of the visible radiation emanating from the apparatus based at least in part on the at least two different ambient illumination conditions.

23. The apparatus of claim 22, further comprising at least one third LED to generate third radiation having a third spectrum different than the first spectrum and the second spectrum, wherein the at least one controller is configured to control a first intensity of the first radiation, a second intensity of the second radiation, and a third intensity of the third radiation so as to provide the at least two different color temperatures of the visible radiation emanating from the apparatus based at least in part on the at least two different ambient illumination conditions.

24. The apparatus of claim 1, wherein the at least one controller is configured to control at least the color temperature of the visible radiation emanating from the apparatus to compensate for the at least one ambient illumination condition.

25. The apparatus of claim 24, wherein:

the at least one ambient illumination condition includes at least one external natural-light ambient illumination condition;

the apparatus is configured to be disposed in an interior space that includes at least one opening through which the at least one external natural-light ambient illumination condition enters the interior space; and

the at least one controller is configured to control at least the color temperature of the visible radiation emanating from the apparatus to compensate for changes in the at least one external natural-light ambient illumination condition so as to maintain essentially stable lighting conditions in the interior space.

26. The apparatus of claim 1, wherein the at least one controller is configured to control at least the color temperature of the visible radiation emanating from the apparatus to simulate the at least one ambient illumination condition.

27. The apparatus of claim 1, wherein the at least one controller is configured to control an intensity and the color temperature of the visible radiation emanating from the apparatus based at least in part on the at least one ambient illumination condition.

28. An apparatus, comprising:

at least one first LED to generate first radiation having a first spectrum;

at least one second LED to generate second radiation having a second spectrum different than the first spectrum;

at least one controller to control at least one of the first radiation and the second radiation so as to control at least a color temperature of visible radiation emanating from the apparatus; and

at least one sensor to monitor at least one characteristic of sample radiation and provide at least one sensor signal to the at least one controller, wherein;

the at least one controller is configured to control at least the color temperature of the visible radiation based at least in part on the at least one sensor signal;

the sample radiation includes at least one desired lighting condition; and

the at least one controller is configured to control at least the color temperature of the visible radiation emanating from the apparatus so as to essentially simulate the at least one desired lighting condition.

29. The apparatus of claim 28, wherein the at least one desired lighting condition corresponds essentially to at least one lighting condition provided by an incandescent light source.

30. The apparatus of claim 28, wherein the at least one desired lighting condition corresponds essentially to at least one lighting condition provided by a fluorescent light source.

31. The apparatus of claim 28, wherein the at least one desired lighting condition corresponds essentially to at least one lighting condition provided by a halogen light source.

32. The apparatus of claim 28, wherein:

the at least one controller includes a processor and a memory; and

the at least one controller is configured to store in the memory a representation of the at least one desired lighting condition based on the at least one sensor signal.

33. The apparatus of claim 28, wherein the at least one controller is configured to control a first intensity of the first radiation and a second intensity of the second radiation so as to essentially simulate the at least one desired lighting condition.

34. The apparatus of claim 33, further comprising at least one third LED to generate third radiation having a third spectrum different than the first spectrum and the second spectrum, wherein the at least one controller is configured to control a first intensity of the first radiation, a second intensity of the second radiation, and a third intensity of the third radiation so as to essentially simulate the at least one desired lighting condition.

83. The apparatus of claim 28, wherein the at least one first LED includes at least one first white LED.

84. The apparatus of claim 83, wherein the at least one second LED includes at least one second white LED.

85. The apparatus of claim 83, further comprising at least one user interface coupled to the at least one controller to permit a user to control the visible radiation.

86. The apparatus of claim 28, wherein the at least one sensor is configured to wirelessly communicate the at least one sensor signal to the at least one controller.

87. The apparatus of claim 28, wherein the at least one sensor is configured to communicate the at least one sensor signal to the at least one controller and at least one other device that is responsive to the at least one sensor signal.

88. The apparatus of claim 28, wherein the at least one sensor includes at least one of a photodiode, a phototransistor, a photomultiplier, a channel-plate intensifier, a charge-coupled device, and an intensified silicon intensifier target (ISIT).

89. The apparatus of claim 28, wherein the at least one sensor includes at least one of a colorimeter, a photometer and a radiometer.

90. The apparatus of claim 28, wherein the at least one sensor includes a camera.

91. The apparatus of claim 28, wherein the at least one characteristic includes at least an intensity of the sample radiation.

92. The apparatus of claim 28, wherein the at least one characteristic includes at least one spectral property of the sample radiation.

93. The apparatus of claim 28, wherein the at least one characteristic includes at least a color temperature of the sample radiation.

94. The apparatus of claim 93, wherein the at least one characteristic includes the color temperature and an intensity of the sample radiation.

35. An apparatus, comprising:

at least one first LED to generate first radiation having a first spectrum;

at least one second LED to generate second radiation having a second spectrum different than the first spectrum;

at least one controller to control at least one of the first radiation and the second radiation so as to control at least a color temperature of visible radiation emanating from the apparatus; and

at least one sensor to monitor at least one characteristic of sample radiation and provide at least one sensor signal to the at least one controller, wherein;

the at least one controller is configured to control at least the color temperature of the visible radiation based at least in part on the at least one sensor signal; and

wherein the sample radiation includes at least some of the visible radiation emanating from the apparatus, such that the at least one sensor signal provides at least one feedback signal to the at least one controller;

wherein the at least one controller is configured to control at least the color temperature of the visible radiation emanating from the apparatus based on a comparison of the at least one feedback signal provided by the at least one sensor and at least one desired lighting condition; and

wherein the at least one desired lighting condition corresponds essentially to at least one lighting condition provided by at least one of an incandescent light source, a fluorescent light source and a halogen light source.

36. An apparatus, comprising:

at least one first LED to generate first radiation having a first spectrum;

at least one second LED to generate second radiation having a second spectrum different than the first spectrum;

at least one controller to control at least one of the first radiation and the second radiation so as to control at least a color temperature of visible radiation emanating from the apparatus; and

at least one sensor to monitor at least one characteristic of sample radiation and provide at least one sensor signal to the at least one controller, wherein;

the at least one controller is configured to control at least the color temperature of the visible radiation based at least in part on the at least one sensor signal; and

wherein the sample radiation includes at least some of the visible radiation emanating from the apparatus, such that the at least one sensor signal provides at least one feedback signal to the at least one controller; and

wherein the at least one controller is configured to control at least the color temperature of the visible radiation emanating from the apparatus based on a comparison of the at least one feedback signal provided by the at least one sensor and at least one desired lighting condition,

the apparatus further including at least one user interface coupled to the at least one controller to permit a user to define or select the at least one desired lighting condition.

37. The apparatus of claim 36, wherein the at least one controller is configured to strobe at least the at least one first LED and the at least one second LED through a plurality of lighting conditions so as to generate the at least one feedback signal.

40. The apparatus of claim 36, wherein the at least one controller is configured to strobe at least the at least one first LED and the at least one second LED through a plurality of lighting conditions until the at least one feedback signal indicates that the at least one desired lighting condition has been substantially obtained.

41. The apparatus of claim 36, wherein the at least one desired lighting condition includes at least two different desired lighting conditions, and wherein the at least one controller is configured to control a first intensity of the first radiation and a second intensity of the second radiation so as to provide at least two different color temperatures of the visible radiation emanating from the apparatus based at least in part on the at least two different desired lighting conditions.

42. The apparatus of claim 41, wherein:

a first desired lighting condition of the at least two different desired lighting conditions corresponds essentially to at least one first lighting condition provided by an incandescent light source; and

a second desired lighting condition of the at least two different desired lighting conditions corresponds essentially to at least one second lighting condition provided by a fluorescent light source.

43. The apparatus of claim 41, further comprising at least one third LED to generate third radiation having a third spectrum different than the first spectrum and the second spectrum,

wherein the at least one controller is configured to control a first intensity of the first radiation, a second intensity of the second radiation, and a third intensity of the third radiation so as to provide the at least two different color temperatures of the visible radiation emanating from the apparatus based at least in part on the at least two different desired lighting conditions.

98. The apparatus of claim 36, wherein the at least one sensor is configured to communicate the at least one sensor signal to the at least one controller and at least one other device that is responsive to the at least one sensor signal.

99. The apparatus of claim 36, wherein the at least one sensor includes at least one of a photodiode, a phototransistor, a photomultiplier, a channel-plate intensifier, a charge-coupled device, and an intensified silicon intensifier target (ISIT).

100. The apparatus of claim 36, wherein the at least one sensor includes at least one of a colorimeter, a photometer and a radiometer.

101. The apparatus of claim 36, wherein the at least one sensor includes a camera.

102. The apparatus of claim 36, wherein the at least one characteristic includes at least an intensity of the sample radiation.

103. The apparatus of claim 36, wherein the at least one characteristic includes at least one spectral property of the sample radiation.

104. The apparatus of claim 36, wherein the at least one characteristic includes at least a color temperature of the sample radiation.

105. The apparatus of claim 104, wherein the at least one characteristic includes the color temperature and an intensity of the sample radiation.

38. An apparatus, comprising:

at least one first LED to generate first radiation having a first spectrum;

at least one second LED to generate second radiation having a second spectrum different than the first spectrum;

at least one controller to control at least one of the first radiation and the second radiation so as to control at least a color temperature of visible radiation emanating from the apparatus; and

at least one sensor to monitor at least one characteristic of sample radiation and provide at least one sensor signal to the at least one controller, wherein;

the at least one controller is configured to control at least the color temperature of the visible radiation based at least in part on the at least one sensor signal; and

wherein the sample radiation includes at least some of the visible radiation emanating from the apparatus, such that the at least one sensor signal provides at least one feedback signal to the at least one controller;

wherein the at least one controller is configured to control at least the color temperature of the visible radiation emanating from the apparatus based on a comparison of the at least one feedback signal provided by the at least one sensor and at least one desired lighting condition; and

wherein;

the at least one controller includes a processor and a memory;

a representation of the at least one desired lighting condition is stored in the memory; and

the processor is programmed to compare the at least one feedback signal and the representation of the at least one desired lighting condition so as to control at least the color temperature of the visible radiation emanating from the apparatus.

39. The apparatus of claim 38, further including at least one user interface coupled to the at least one controller to permit a user to define or select the representation of the at least one desired lighting condition.

44. An apparatus, comprising:

at least one first LED to generate first radiation having a first spectrum;

at least one second LED to generate second radiation having a second spectrum different than the first spectrum;

at least one controller to control at least one of the first radiation and the second radiation so as to control at least a color temperature of visible radiation emanating from the apparatus;

at least one sensor to monitor at least one characteristic of sample radiation and provide at least one sensor signal to the at least one controller, wherein the at least one controller is configured to control at least the color temperature of the visible radiation based at least in part on the at least one sensor signal; and

at least one housing to support at least the at least one first LED and the at least one second LED, wherein the at least one housing is configured to resemble a conventional light bulb, and wherein the housing comprises at least one connector that is adapted to engage mechanically and electrically with a conventional light socket arrangement.

45. The apparatus of claim 44, wherein the at least one connector is adapted to engage mechanically and electrically with one of an incandescent light socket arrangement, a fluorescent light socket arrangement, and a halogen light socket arrangement.

46. A method, comprising acts of:

A) energizing at least one first LED to generate first radiation having a first spectrum;

B) energizing at least one second LED to generate second radiation having a second spectrum different than the first spectrum;

C) controlling at least one of the first radiation and the second radiation so as to control at least a color temperature of visible radiation; and

D) monitoring at least one characteristic of sample radiation,

wherein the act C) includes an act of controlling at least one of the first radiation and the second radiation so as to control at least a color temperature of visible radiation based on the act D),

wherein the sample radiation includes at least one ambient illumination condition, and wherein the act C) comprises an act of;

C1) controlling at least the color temperature of the visible radiation based at least in part on the at least one ambient illumination condition.

47. The method of claim 46, wherein the at least one first LED includes at least one first white LED.

48. The method of claim 47, wherein the at least one second LED includes at least one second white LED.

49. The method of claim 46, further comprising an act of controlling the visible radiation at least in part via at least one user interface.

50. The method of claim 46, wherein the at least one characteristic includes at least an intensity of the sample radiation.

51. The method of claim 46, wherein the at least one characteristic includes at least one spectral property of the sample radiation.

52. The method of claim 46, wherein the at least one characteristic includes at least a color temperature of the sample radiation.

53. The method of claim 52, wherein the at least one characteristic includes the color temperature and an intensity of the sample radiation.

54. The method of claim 46, wherein the at least one ambient illumination condition includes at least one external natural-light ambient illumination condition.

55. The method of claim 46, wherein the at least one ambient illumination condition includes at least two different ambient illumination conditions, and wherein the act C1) comprises an act of:

controlling a first intensity of the first radiation and a second intensity of the second radiation so as to provide at least two different color temperatures of the visible radiation based at least in part on the at least two different ambient illumination conditions.

56. The method of claim 55, wherein the method further comprises an act of:

energizing at least one third LED to generate third radiation having a third spectrum different than the first spectrum and the second spectrum,

and wherein the act C1) comprises an act of;

controlling a first intensity of the first radiation, a second intensity of the second radiation, and a third intensity of the third radiation so as to provide the at least two different color temperatures of the visible radiation based at least in part on the at least two different ambient illumination conditions.

57. The method of claim 46, wherein the act C1) comprises an act of:

controlling at least the color temperature of the visible radiation to compensate for the at least one ambient illumination condition.

58. The method of claim 57, wherein the at least one ambient illumination condition includes at least one external natural-light ambient illumination condition, and wherein the act C1) comprises an act of:

controlling at least the color temperature of the visible radiation to compensate for changes in the at least one external natural-light ambient illumination condition so as to maintain essentially stable lighting conditions in an interior space that is exposed to the at least one external natural-light ambient illumination condition.

59. The method of claim 46, wherein the act C1) comprises an act of:

controlling at least the color temperature of the visible radiation so as to simulate the at least one ambient illumination condition.

60. The method of claim 46, wherein the act C1) comprises an act of:

controlling an intensity and the color temperature of the visible radiation based at least in part on the at least one ambient illumination condition.

61. A method, comprising acts of:

A) energizing at least one first LED to generate first radiation having a first spectrum;

B) energizing at least one second LED to generate second radiation having a second spectrum different than the first spectrum;

C) controlling at least one of the first radiation and the second radiation so as to control at least a color temperature of visible radiation; and

D) monitoring at least one characteristic of sample radiation,

wherein the act C) includes an act of controlling at least one of the first radiation and the second radiation so as to control at least a color temperature of visible radiation based on the act D),

wherein the sample radiation includes at least one desired lighting condition, and wherein the act C) comprises an act of;

C1) controlling at least the color temperature of the visible radiation so as to essentially simulate the at least one desired lighting condition.

62. The method of claim 61, wherein the at least one desired lighting condition corresponds essentially to at least one lighting condition provided by an incandescent light source.

63. The method of claim 61, wherein the at least one desired lighting condition corresponds essentially to at least one lighting condition provided by a fluorescent light source.

64. The method of claim 61, wherein the at least one desired lighting condition corresponds essentially to at least one lighting condition provided by a halogen light source.

65. The method of claim 61, further comprising an act of:

storing in memory a representation of the at least one desired lighting condition based on the act D).

66. The method of claim 61, wherein the act C1) comprises an act of:

controlling a first intensity of the first radiation and a second intensity of the second radiation so as to essentially simulate the at least one desired lighting condition.

67. The method of claim 66, further comprising an act of:

energizing at least one third LED to generate third radiation having a third spectrum different than the first spectrum and the second spectrum,

wherein the act C1) comprises an act of;

control a first intensity of the first radiation, a second intensity of the second radiation, and a third intensity of the third radiation so as to essentially simulate the at least one desired lighting condition.

68. A method, comprising acts of:

A) energizing at least one first LED to generate first radiation having a first spectrum;

B) energizing at least one second LED to generate second radiation having a second spectrum different than the first spectrum;

C) controlling at least one of the first radiation and the second radiation so as to control at least a color temperature of visible radiation; and

D) monitoring at least one characteristic of sample radiation,

wherein the act C) includes an act of controlling at least one of the first radiation and the second radiation so as to control at least a color temperature of visible radiation based on the act D),

wherein the sample radiation includes at least some of the visible radiation, and wherein the method further comprises an act of;

generating at least one feedback signal based on the act D),

wherein the act C) comprises an act of;

C1) controlling at least the color temperature of the visible radiation based on a comparison of the at least one feedback signal and at least one desired lighting condition; and

wherein the at least one desired lighting condition corresponds essentially to at least one lighting condition provided by at least one of an incandescent light source, a fluorescent light source, and a halogen light source.

69. A method, comprising acts of:

A) energizing at least one first LED to generate first radiation having a first spectrum;

B) energizing at least one second LED to generate second radiation having a second spectrum different than the first spectrum;

C) controlling at least one of the first radiation and the second radiation so as to control at least a color temperature of visible radiation; and

D) monitoring at least one characteristic of sample radiation,

wherein the act C) includes an act of controlling at least one of the first radiation and the second radiation so as to control at least a color temperature of visible radiation based on the act D),

wherein the sample radiation includes at least some of the visible radiation, and wherein the method further comprises an act of;

generating at least one feedback signal based on the act D),

wherein the act C) comprises an act of;

C1) controlling at least the color temperature of the visible radiation based on a comparison of the at least one feedback signal and at least one desired lighting condition,

the method further comprising an act of defining or selecting the at least one desired lighting condition via at least one user interface.

70. The method of claim 69, further comprising an act of:

strobing at least the at least one first LED and the at least one second LED through a plurality of lighting conditions so as to generate the at least one feedback signal.

73. The method of claim 69, wherein the act C1) comprises an act of:

strobing at least the at least one first LED and the at least one second LED through a plurality of lighting conditions until the at least one feedback signal indicates that the at least one desired lighting condition has been substantially obtained.

74. The method of claim 69, wherein the at least one desired lighting condition includes at least two different desired lighting conditions, and wherein the act D1) comprises an act of:

controlling a first intensity of the first radiation and a second intensity of the second radiation so as to provide at least two different color temperatures of the visible radiation based at least in part on the at least two different desired lighting conditions.

75. The method of claim 74, wherein:

a first desired lighting condition of the at least two different desired lighting conditions corresponds essentially to at least one first lighting condition provided by an incandescent light source; and

a second desired lighting condition of the at least two different desired lighting conditions corresponds essentially to at least one second lighting condition provided by a fluorescent light source.

76. The method of claim 74, further comprising an act of:

energizing at least one third LED to generate third radiation having a third spectrum different than the first spectrum and the second spectrum,

wherein the act C1) comprises an act of;

controlling a first intensity of the first radiation, a second intensity of the second radiation, and a third intensity of the third radiation so as to provide the at least two different color temperatures of the visible radiation based at least in part on the at least two different desired lighting conditions.

71. A method, comprising acts of:

A) energizing at least one first LED to generate first radiation having a first spectrum;

B) energizing at least one second LED to generate second radiation having a second spectrum different than the first spectrum;

C) controlling at least one of the first radiation and the second radiation so as to control at least a color temperature of visible radiation; and

D) monitoring at least one characteristic of sample radiation,

wherein the act C) includes an act of controlling at least one of the first radiation and the second radiation so as to control at least a color temperature of visible radiation based on the act D),

wherein the sample radiation includes at least some of the visible radiation, and wherein the method further comprises an act of;

generating at least one feedback signal based on the act D),

wherein the act C) comprises an act of;

C1) controlling at least the color temperature of the visible radiation based on a comparison of the at least one feedback signal and at least one desired lighting condition,

the method further comprising acts of;

storing a representation of the at least one desired lighting condition in memory; and

comparing the at least one feedback signal and the representation of the at least one desired lighting condition so as to control at least the color temperature of the visible radiation.

72. The method of claim 71, further comprising an act of defining or selecting the representation of the at least one desired lighting condition via at least one user interface.

77. A system, comprising:

a first apparatus comprising;

at least one first LED to generate first radiation having a first spectrum;

at least one second LED to generate second radiation having a second spectrum different than the first spectrum; and

at least one first controller to control at least one of the first radiation and the second radiation so as to control at least a first color temperature of first visible radiation emanating from the first apparatus;

a second apparatus comprising;

at least one third LED to generate third radiation having a third spectrum;

at least one fourth LED to generate fourth radiation having a fourth spectrum different than the third spectrum; and

at least one second controller to control at least one of the third radiation and the fourth radiation so as to control at least a second color temperature of second visible radiation emanating from the second apparatus; and

at least one sensor to monitor at least one characteristic of sample radiation and provide at least one sensor signal to the at least one first controller and the at least one second controller,

wherein the at least one first controller is configured to control at least the first color temperature of the first visible radiation based at least in part on the at least one sensor signal, and wherein the at least one second controller is configured to control at least the second color temperature of the second visible radiation based at least in part on the at least one sensor signal.

78. The system of claim 77, wherein the first spectrum and the third spectrum are essentially identical, and wherein the second spectrum and the fourth spectrum are essentially identical.

79. The system of claim 77, wherein:

the sample radiation includes at least one ambient illumination condition; and

the at least one first controller and the at least one second controller are configured to respectively control at least the first color temperature of the first visible radiation and the second color temperature of the second visible radiation based at least in part on the at least one ambient illumination condition.

80. The system of claim 77, wherein:

the sample radiation includes at least one desired lighting condition; and

the at least one first controller and the at least one second controller are configured to respectively control at least the first color temperature of the first visible radiation and the second color temperature of the second visible radiation so as to essentially simulate the at least one desired lighting condition.

81. The system of claim 77, wherein the sample radiation includes at least one of the first visible radiation emanating from the first apparatus and the second visible radiation emanating from the second apparatus, such that the at least one sensor signal provides at least one feedback signal to at least one of the at least one first controller and the at least one second controller.

82. The system of claim 81, wherein the at least one of the at least one first controller and the at least one second controller is configured to control at least a corresponding one of the first color temperature of the first visible radiation and the second color temperature of the second visible radiation based on a comparison of the at least one feedback signal provided by the at least one sensor and at least one desired lighting condition.

95. An apparatus, comprising:

at least one first LED to generate first radiation having a first spectrum;

at least one second LED to generate second radiation having a second spectrum different than the first spectrum;

at least one controller to control at least one of the first radiation and the second radiation so as to control at least a color temperature of visible radiation emanating from the apparatus; and

at least one sensor to monitor at least one characteristic of sample radiation and provide at least one sensor signal to the at least one controller, wherein;

the at least one controller is configured to control at least the color temperature of the visible radiation based at least in part on the at least one sensor signal;

wherein the sample radiation includes at least some of the visible radiation emanating from the apparatus, such that the at least one sensor signal provides at least one feedback signal to the at least one controller; and

wherein the at least one first LED includes at least one first white LED,

the apparatus further comprising at least one user interface coupled to the at least one controller to permit a user to control the visible radiation.

96. The apparatus of claim 95, wherein the at least one second LED includes at least one second white LED.

97. An apparatus, comprising:

at least one first LED to generate first radiation having a first spectrum;

at least one second LED to generate second radiation having a second spectrum different than the first spectrum;

at least one controller to control at least one of the first radiation and the second radiation so as to control at least a color temperature of visible radiation emanating from the apparatus; and

at least one sensor to monitor at least one characteristic of sample radiation and provide at least one sensor signal to the at least one controller, wherein;

the at least one controller is configured to control at least the color temperature of the visible radiation based at least in part on the at least one sensor signal;

wherein the sample radiation includes at least some of the visible radiation emanating from the apparatus, such that the at least one sensor signal provides at least one feedback signal to the at least one controller; and

wherein the at least one sensor is configured to wirelessly communicate the at least one sensor signal to the at least one controller.