Regulation of wavelength shift and perceived color of solid state lighting with intensity and temperature variation

• US 8,253,666 B2
• Filed: 10/29/2007
• Issued: 08/28/2012
• Est. Priority Date: 09/21/2007
• Status: Active Grant

• Current Assignee: Chemtron Research LLC (Intellectual Ventures LLC)
• Original Assignee: Point Somee LLC (Intellectual Ventures LLC)
• Inventors: Shteynberg, Anatoly, Rodriguez, Harry, Lehman, Bradley M., Zhou, Dongsheng
• Primary Examiner(s): Lao, Lun-Yi
• Assistant Examiner(s): MERKOULOVA, OLGA VLADIMIROVNA
• Application Number:
  US11/927,302
• Publication Number:
  US 20090079362A1
• Time in Patent Office: 1,765 Days
• Field of Search: 345 76- 83, 345/39, 345/63, 345/204, 315/169.3, 315208-210, 313/463, 313/498
• US Class Current: 345/82
• CPC Class Codes: H05B 45/20 Controlling the colour of the light
• CPC Class Codes: H05B 45/24 using electrical feedback from LEDs or from LED modules
• CPC Class Codes: H05B 45/28 using temperature feedback
• CPC Class Codes: H05B 45/46 having LEDs disposed in parallel lines

Abstract

Representative embodiments of the disclosure provide a system, apparatus, and method of controlling an intensity and spectrum of light emitted from a solid state lighting system. The solid state lighting system has a first emitted spectrum at full intensity and at a selected temperature, with a first electrical biasing for the solid state lighting system producing a first wavelength shift, and a second electrical biasing for the solid state lighting system producing a second, opposing wavelength shift. Representative embodiments provide for receiving information designating a selected intensity level or a selected temperature and providing a combined first electrical biasing and second electrical biasing to the solid state lighting system to generate emitted light having the selected intensity level and having a second emitted spectrum within a predetermined variance of the first emitted spectrum over a predetermined range of temperatures.

Claims

1. An illumination control method for a plurality of light emitting diodes, the method comprising:

monitoring an input control signal, wherein the input control signal designates a first intensity level for one or more first light emitting diodes having a first spectrum and a second intensity level for one or more second light emitting diodes having a second spectrum different from the first spectrum;

determining a first temperature associated with the one or more first light emitting diodes;

determining a second temperature associated with the one or more second light emitting diodes;

retrieving a first plurality of parameters stored in a memory, wherein the first plurality of parameters designates a corresponding combination of a first electrical biasing and a second electrical biasing for the first temperature, wherein the first electrical biasing for the one or more first light emitting diodes is configured to produce a first wavelength shift, and wherein the second electrical biasing for the one or more first light emitting diodes is configured to produce a second wavelength shift that is opposed to the first wavelength shift;

retrieving a second plurality of parameters stored in the memory, wherein the second plurality of parameters designates a corresponding combination of a third electrical biasing and a fourth electrical biasing for the second temperature, wherein the third electrical biasing for the one or more second light emitting diodes is configured to produce a third wavelength shift, and wherein the fourth electrical biasing for the one or more second light emitting diodes is configured to produce a fourth wavelength shift that is opposed to the third wavelength shift;

processing the first plurality of parameters into a first input electrical biasing control signal for the one or more first light emitting diodes;

processing the second plurality of parameters into a second input electrical biasing control signal for the one or more second light emitting diodes;

operating the one or more first light emitting diodes with a first time-averaged modulation of forward current conforming to the first input electrical biasing control signal to provide a substantially constant first intensity level over a predetermined temperature range and having an emitted spectrum within a first predetermined variance of the first spectrum; and

operating the one or more second light emitting diodes with a second time-averaged modulation of forward current conforming to the second input electrical biasing control signal to provide a substantially constant second intensity level over the predetermined temperature range having an emitted spectrum within a second predetermined variance of the second spectrum.

2. The method of claim 1, wherein the first predetermined variance and the second predetermined variance are each substantially close to zero.

3. The method of claim 1, wherein the input control signal is provided by at least one of the following:

a lighting controller, a microprocessor, a remote controller, an AC phase modulation controller, or a manual controller.

4. The method of claim 1, wherein the input control signal has an analog or digital form compatible with an input interface of a controller of an LED driver.

5. The method of claim 1, further comprising:

selecting the first electrical biasing for corresponding p-n junctions of the at least one or more first light-emitting diodes to produce the first wavelength shift in response to temperature variation;

selecting the second electrical biasing for the corresponding p-n junctions of the one or more first light emitting diodes to produce the second, opposing wavelength shift in response to temperature variation;

selecting the third electrical biasing for corresponding p-n junctions of the one or more second light emitting diodes to produce the third wavelength shift in response to temperature variation; and

selecting the fourth electrical biasing for the corresponding p-n junctions of the one or more second light emitting diodes to produce the fourth, opposing wavelength shift in response to temperature variation.

6. The method of claim 5, further comprising:

statistically characterizing the one or more first light emitting diodes for the first electrical biasing and the second electrical biasing as a function of temperature variation; and

statistically characterizing the one or more second light emitting diodes for the third electrical biasing and the fourth electrical biasing as a function of temperature variation.

7. The method of claim 6, further comprising:

theoretically predicting the combination of the first electrical biasing and the second electrical biasing to control wavelength shifts of the one or more first light emitting diodes as a function of temperature; and

theoretically predicting the combination of the third electrical biasing and the fourth electrical biasing to control wavelength shifts of the one or more second light emitting diodes as a function of temperature.

8. The method of claim 7, further comprising:

theoretically predicting the combinations to provide any wavelength shifts, as a function of temperature, are substantially close to zero.

9. The method of claim 7, further comprising:

storing the predicted combination of the first electrical biasing and the second electrical biasing as the first plurality of parameters in the memory of a controller for a driver circuit for the one or more first light emitting diodes; and

storing the predicted combination of the third electrical biasing and the fourth electrical biasing as the second plurality of parameters in the memory of a controller for a driver circuit for the one or more second light emitting diodes.

10. The method of claim 7, further comprising:

storing the predicted combinations as the first and second pluralities of parameters in the form of a look-up table.

11. The method of claim 7, further comprising:

storing each predicted combination as a corresponding linear or functional equation for temperature variation.

12. The method of claim 1, wherein the first, second, third and fourth electrical biasings are a forward current or bias voltage of the one or more first or second light emitting diodes.

13. The method of claim 1, wherein at least one of the first, second, third and fourth electrical biasings is an adaptation of an average DC current using any waveform of analog current control.

14. The method of claim 1, wherein at least one of the first, second, third and fourth electrical biasings is a pulse modulated current.

15. The method of claim 1, wherein at least one of the first, second, third and fourth electrical biasings is one of the following:

pulse width modulation, pulse frequency modulation, pulse amplitude modulation, or a time-averaged pulse modulated current.

16. The method of claim 1, further comprising:

independently controlling the first intensity and the second intensity within a predetermined spectral variance to regulate an overall color generated by the plurality of light emitting diodes, wherein said independently controlling is configured to;

provide that an overall color generated by the plurality of light emitting diodes comprises a sequence of a plurality of single colors emitted during corresponding time intervals;

dim the light generated by the plurality of light emitting diodes;

produce a dynamic lighting effect from the plurality of light emitting diodes;

or

regulate a color temperature of the light generated by the plurality of light emitting diodes.

17. The method of claim 1, further comprising:

synchronizing the combination of the first electrical biasing and second electrical biasing with a first switching cycle of a first switch mode LED driver; and

synchronizing the combination of the third electrical biasing and fourth electrical biasing with a second switching cycle of a second switch mode LED driver.

18. The method of claim 17, further comprising:

updating a first frame synchronization register associated with a first controller of the one or more first light emitting diodes to store the first input electrical biasing control signal; and

updating a second frame synchronization register associated with a second controller of the one or more second light emitting diodes to store the second input electrical biasing control signal.

19. The method of claim 18, further comprising:

updating the first frame synchronization register with a new first input electrical biasing control signal beginning at each fixed period of time synchronized to first switching frequency; and

updating the second frame synchronization register with a new second input electrical biasing control signal beginning at each fixed period of time synchronized to second switching frequency.

20. The method of claim 1, further comprising:

reducing flickering by synchronizing the combination of the first electrical biasing and second electrical biasing with a first switching cycle of a first switch mode LED driver and synchronizing the combination of the third electrical biasing and fourth electrical biasing with a second switching cycle of a second switch mode LED driver.

21. An illumination control method to vary intensity of light from a plurality of light emitting diodes, the method comprising:

monitoring an input control signal, wherein the input control signal designates a first intensity level for one or more first light emitting diodes having a first spectrum and a second intensity level for one or more second light emitting diodes having a second spectrum different from the first spectrum;

determining a first temperature associated with the one or more first light emitting diodes;

determining a second temperature associated with the one or more second light emitting diodes;

retrieving a first plurality of parameters stored in a memory, wherein the first plurality of parameters designates a corresponding combination of a first electrical biasing and a second electrical biasing for the first intensity level and the first temperature, wherein the first electrical biasing for the one or more first light emitting diodes is configured to produce a first wavelength shift, and wherein the second electrical biasing for the one or more first light emitting diodes is configured to produce a second wavelength shift that is opposed to the first wavelength shift;

retrieving a second plurality of parameters stored in the memory, wherein the second plurality of parameters designates a corresponding combination of a third electrical biasing and a fourth electrical biasing for the second intensity level and the second temperature, wherein the third electrical biasing for the one or more second light emitting diodes is configured to produce a third wavelength shift, and wherein the fourth electrical biasing for the one or more second light emitting diodes is configured to produce a fourth wavelength shift that is opposed to the third wavelength shift;

processing the first plurality of parameters into a first input electrical biasing control signal for the one or more first light emitting diodes;

processing the second plurality of parameters into a second input electrical biasing control signal for the one or more second light emitting diodes;

operating the one or more first light emitting diodes with a first time-averaged modulation of forward current conforming to the first input electrical biasing control signal to provide the first intensity level having an emitted spectrum within a first predetermined variance of the first spectrum over a predetermined range of temperatures; and

operating the one or more second light emitting diodes with a second time-averaged modulation of forward current conforming to the second input electrical biasing control signal to provide the second intensity level having an emitted spectrum within a second predetermined variance of the second spectrum over the predetermined range of temperatures.

22. The method of claim 21, wherein the first predetermined variance and the second predetermined variance are each substantially close to zero.

23. The method of claim 21, wherein the input control signal is provided by at least one of the following:

a lighting controller, a microprocessor, a remote controller, an AC phase modulation controller, or a manual controller.

24. The method of claim 21, wherein the input control signal has an analog or digital form compatible with an input interface of a controller of an LED driver.

25. The method of claim 21, further comprising:

selecting the first electrical biasing for corresponding p-n junctions of the one or more first light emitting diodes to produce the first wavelength shift in response to variation of both intensity and temperature;

selecting the second electrical biasing for the corresponding p-n junctions of the one or more first light emitting diodes to produce the second, opposing wavelength shift in response to variation of both intensity and temperature;

selecting the third electrical biasing for corresponding p-n junctions of the one or more second light emitting diodes to produce the third wavelength shift in response to variation of both intensity and temperature; and

selecting the fourth electrical biasing for the corresponding p-n junctions of the one or more second light emitting diodes to produce the fourth, opposing wavelength shift in response to variation of both intensity and temperature.

26. The method of claim 25, further comprising:

statistically characterizing the one or more first light emitting diodes for the first electrical biasing and the second electrical biasing as a function of variation of both intensity and temperature; and

statistically characterizing the one or more second light emitting diodes for the third electrical biasing and the fourth electrical biasing as a function of variation of both intensity and temperature.

27. The method of claim 26, further comprising:

theoretically predicting the combination of the first electrical biasing and the second electrical biasing to control wavelength shifts of the one or more first light emitting diodes as a function of variation of both intensity and temperature; and

theoretically predicting the combination of the third electrical biasing and the fourth electrical biasing to control wavelength shifts of the one or more second light emitting diodes as a function of variation of both intensity and temperature.

28. The method of claim 27, further comprising:

theoretically predicting the combinations to provide any wavelength shifts, as a function of temperature and intensity variation, are substantially close to zero.

29. The method of claim 27, further comprising:

storing the predicted combination of the first electrical biasing and the second electrical biasing as the first plurality of parameters in the memory of a controller for a driver circuit for the one or more first light emitting diodes; and

storing the predicted combination of the third electrical biasing and the fourth electrical biasing as the second plurality of parameters in the memory of a controller for a driver circuit for the one or more second light emitting diodes.

30. The method of claim 27, further comprising:

storing the predicted combinations as the first and second pluralities of parameters in the form of a look-up table.

31. The method of claim 27, further comprising:

storing each predicted combination as a corresponding linear or functional equation for variation of both intensity and temperature.

32. The method of claim 21, wherein the first, second, third and fourth electrical biasings are a forward current or bias voltage of the one or more first or second light emitting diodes.

33. The method of claim 21, wherein at least one of the first, second, third and fourth electrical biasings is an adaptation of an average DC current using any waveform of analog current control.

34. The method of claim 21, wherein at least one of the first, second, third and fourth electrical biasings is a pulse modulated current.

35. The method of claim 21, wherein at least one of the first, second, third, and fourth electrical biasings is one of the following:

pulse width modulation, pulse frequency modulation, pulse amplitude modulation, or a time-averaged pulse modulated current.

36. The method of claim 21, wherein the corresponding combinations are a first combination of non-zero first electrical biasing and second electrical biasing to regulate wavelength emission while maintaining an average first intensity substantially constant and a second combination of non-zero third electrical biasing and fourth electrical biasing to regulate wavelength emission while maintaining an average second intensity substantially constant.

37. The method of claim 21, further comprising:

independently controlling the first intensity and the second intensity within a predetermined spectral variance over a predetermined range of temperatures to regulate an overall color generated by the plurality of light emitting diodes, wherein said independently controlling is configured to;

provide that an overall color generated by the plurality of light emitting diodes comprises a sequence of a plurality of single colors emitted during corresponding time intervals;

dim the light generated by the plurality of light emitting diodes;

produce a dynamic lighting effect from the plurality of light emitting diodes;

or

regulate a color temperature of the light generated by the plurality of light emitting diodes.

38. The method of claim 21, further comprising:

synchronizing the combination of the first electrical biasing and second electrical biasing with a first switching cycle of a first switch mode LED driver; and

synchronizing the combination of the third electrical biasing and fourth electrical biasing with a second switching cycle of a second switch mode LED driver.

39. The method of claim 38, further comprising:

updating a first frame synchronization register associated with a first controller of the one or more first light emitting diodes to store the first input electrical biasing control signal; and

updating a second frame synchronization register associated with a second controller of the one or more second light emitting diodes to store the one second input electrical biasing control signal.

40. The method of claim 39, further comprising:

updating the first frame synchronization register with a new first input electrical biasing control signal beginning at each fixed period of time synchronized to first switching frequency; and

updating the second frame synchronization register with a new second input electrical biasing control signal beginning at each fixed period of time synchronized to second switching frequency.

41. The method of claim 21, further comprising:

reducing flickering by synchronizing the combination of the first electrical biasing and second electrical biasing with a first switching cycle of a first switch mode LED driver and synchronizing the combination of the third electrical biasing and fourth electrical biasing with a second switching cycle of a second switch mode LED driver.

42. A lighting system having variable intensity, the system comprising:

a plurality of light emitting diodes, wherein the plurality of light emitting diodes includes;

one or more first light emitting diodes connected in a first channel and having a first spectrum;

one or more second light emitting diodes connected in a second channel and having a second, different spectrum;

a first electrical biasing for the one or more first light emitting diodes configured to produce a first wavelength shift;

a second electrical biasing for the one or more first light emitting diodes configured to produce a second wavelength shift that is opposed to the first wavelength shift;

a third electrical biasing for the one or more second light emitting diodes configured to produce a third wavelength shift;

a fourth electrical biasing for the one or more second light emitting diodes configured to produce a fourth wavelength shift that is opposed to the third wavelength shift;

a temperature sensor coupled to the one or more first light emitting diodes of the plurality of light emitting diodes;

a first driver circuit coupled to the one or more first light emitting diodes, wherein the first driver circuit comprises a first regulator and a first power converter, and wherein the first driver circuit is configured to respond to a first plurality of input operational signals to provide a first combination of the first electrical biasing and the second electrical biasing to the one or more first light emitting diodes;

a second driver circuit coupled to the at least one or more second light emitting diodes, wherein the second driver circuit comprises a second regulator and a second power converter, and wherein the second driver circuit is configured to respond to a second plurality of input operational signals to provide a second combination of the third electrical biasing and the fourth electrical biasing to the one or more second light emitting diodes;

a first controller couplable to a user interface and coupled to the first driver circuit, wherein the first controller comprises a first memory, wherein the first controller is configured to retrieve a first plurality of parameters stored in the first memory, wherein the first plurality of parameters corresponds to a sensed temperature and to a first intensity level provided by the user interface and further designates the first combination of the first electrical biasing and the second electrical biasing, and wherein the first controller is further configured to convert the first plurality of parameters into a first input operational control signal to provide the first intensity level of the one or more first light emitting diodes with wavelength emission control over a predetermined range of temperatures; and

a second controller couplable to the user interface and coupled to the second driver circuit, wherein the second controller comprises a second memory, wherein the second controller to retrieve a second plurality of parameters stored in the second memory, wherein the second plurality of parameters corresponds to the sensed temperature and to a second intensity level provided by the user interface and further designates the second combination of the third electrical biasing and the fourth electrical biasing, and wherein the second controller is further configured to convert the second plurality of parameters into a second input operational control signal to provide the second intensity level of the one or more second light emitting diodes with wavelength emission control over the predetermined range of temperatures.

43. The lighting system of claim 42, wherein emitted light from the one or more first light emitting diodes at the first intensity level has a first peak wavelength within a first predetermined variance of a first full intensity peak wavelength and wherein emitted light from the one or more second light emitting diodes at the second intensity level has a second peak wavelength within a second predetermined variance of a second full intensity peak wavelength.

44. The lighting system of claim 42, wherein the first controller is configured to independently control the first intensity and wavelength emission of the one or more first light emitting diodes, and wherein the second controller is configured to independently control the second intensity and wavelength emission of the one or more second light emitting diodes to regulate an overall color generated by the lighting system.

45. The lighting system of claim 42, wherein the at least one first controller is configured to independently control the first intensity and wavelength emission of the one or more first light emitting diodes, and wherein the second controller is configured to independently control the second intensity and wavelength emission of the one or more second light emitting diodes to provide that an overall color generated by the plurality of light emitting diodes comprises a sequence of a plurality of single colors emitted during corresponding time intervals.

46. The lighting system of claim 42, wherein the at least one first controller is configured to independently control the first intensity and wavelength emission of the one or more first light emitting diodes, and wherein the second controller is configured to independently control the second intensity and wavelength emission of the one or more second light emitting diodes to dim the light generated by the plurality of light emitting diodes.

47. The lighting system of claim 42, wherein the at least one first controller is configured to independently control the first intensity and wavelength emission of the one or more first light emitting diodes, and wherein the second controller is configured to independently control the second intensity and wavelength emission of the one or more second light emitting diodes to produce a dynamic lighting effect selected through the user interface.

48. The lighting system of claim 42, wherein the at least one first controller is configured to independently control the first intensity and wavelength emission of the one or more first light emitting diodes, and wherein the second controller is configured to independently control the second intensity and wavelength emission of the one or more second light emitting diodes to regulate a color temperature of the light generated by the plurality of light emitting diodes.

49. The lighting system of claim 42, wherein the first, second, third, and fourth electrical biasings are a forward current or bias voltage of the one or more first or second light emitting diodes.

50. The lighting system of claim 42, wherein at least one of the first, second, third, and fourth electrical biasings is an adaptation of an average DC current using any waveform of analog current control.

51. The lighting system of claim 42, wherein at least one of the first, second, third, and fourth electrical biasings is a pulse modulated current.

52. The lighting system of claim 42, wherein at least one of the first, second, third, and fourth electrical biasings is one of the following:

pulse width modulation, pulse frequency modulation, pulse amplitude modulation, or a time-averaged pulse modulated current.

53. The lighting system of claim 42, wherein the first controller is configured to generate the first input operational control signal to provide a first combination of non-zero first electrical biasing and second electrical biasing to regulate wavelength emission while maintaining the average first intensity substantially constant.

54. The lighting system of claim 42, wherein the at least one second controller is configured to generate the second input operational control signal to provide a second combination of non-zero third electrical biasing and fourth electrical biasing to regulate wavelength emission while maintaining the average second intensity substantially constant.

55. The lighting system of claim 42, wherein the first controller is further configured to generate the first input electrical biasing control signal to provide both the first intensity level and a corresponding wavelength shift within a first predetermined variance of the first spectrum, and wherein the second controller is further configured to generate the second input electrical biasing control signal to provide both the second intensity level independently of the first intensity level and a corresponding wavelength shift within a second predetermined variance of the second spectrum.

56. The lighting system of claim 42, wherein the first controller and the second controller are further configured to control the first intensity and the second intensity within a predetermined spectral variance to regulate an overall color generated by the plurality of light emitting diodes.

57. The lighting system of claim 42, wherein the first controller and the second controller are further configured to control the first intensity and the second intensity within a predetermined spectral variance to provide that an overall color generated by the plurality of light emitting diodes comprises a sequence of a plurality of single colors emitted during corresponding time intervals.

58. The lighting system of claim 42, wherein the first controller and the second controller are further configured to control the first intensity and the second intensity within a predetermined spectral variance to dim the light generated by the plurality of light emitting diodes.

59. The lighting system of claim 42, wherein the first controller and the second controller are further configured to control the first intensity and the second intensity within a predetermined spectral variance to produce a dynamic lighting effect from the plurality of light emitting diodes.

60. The lighting system of claim 42, wherein the first controller and the second controller are further configured to control the first intensity and the second intensity within a predetermined spectral variance to regulate a color temperature of the light generated by the plurality of light emitting diodes.

61. The lighting system of claim 42, wherein the first plurality of parameters are a prediction of the combination of the first electrical biasing and the second electrical biasing to control both intensity and wavelength shifts of the one or more first light emitting diodes over the predetermined range of temperatures, and wherein the second plurality of parameters are a prediction of the combination of the third electrical biasing and the fourth electrical biasing to control both intensity and wavelength shifts of the one or more second light emitting diodes over the predetermined range of temperatures.

62. The lighting system of claim 42, wherein the first plurality of parameters are a prediction of the combination of the first electrical biasing and the second electrical biasing to control intensity of and to provide any wavelength shifts are substantially close to zero for the one or more first light emitting diodes over the predetermined range of temperatures, and wherein the second plurality of parameters are a prediction of the combination of the third electrical biasing and the fourth electrical biasing to control intensity of and to provide any wavelength shifts are substantially close to zero for the one or more second light emitting diodes over the predetermined range of temperatures.

63. The lighting system of claim 42, wherein the first plurality of parameters are a prediction of the operation of the one or more first light emitting diodes from the application of the combination of the first electrical biasing and the second electrical biasing during symmetrical or asymmetrical dimming cycles for a predetermined range of intensity variation over the predetermined range of temperatures, and wherein the second plurality of parameters are a prediction of the operation of the one or more second light emitting diodes from the application of the combination of the third electrical biasing and the fourth electrical biasing during symmetrical or asymmetrical dimming cycles for the predetermined range of intensity variation over the predetermined range of temperatures.

64. The lighting system of claim 42, wherein the first and second pluralities of parameters are each stored in the form of a look-up table in the respective first and second memories.

65. The lighting system of claim 42, wherein the first and second pluralities of parameters are each stored in the form of a linear or functional equation for intensity adjustment within every dimming cycle or every second dimming cycle for the corresponding electrical biasings.

66. The lighting system of claim 42, wherein the combination of the first electrical biasing and second electrical biasing or the combination of the third electrical biasing and fourth electrical biasing is at least one of the following:

a combination of pulse width modulation and constant current regulation within a single dimming cycle;

a combination of forward current pulse modulation and analog regulation alternating every two consecutive dimming cycles;

a combination of forward current pulse modulation and analog regulation alternating every three consecutive dimming cycles;

a combination of forward current pulse modulation and analog regulation alternating an equal number of consecutive dimming cycles;

or a combination of forward current pulse modulation and analog regulation alternating an unequal number of consecutive dimming cycles.

67. The lighting system of claim 42, wherein the combination of the first electrical biasing and second electrical biasing or the combination of the third electrical biasing and fourth electrical biasing comprises forward current pulse modulation with a peak current in a high state and an average current value at a low state.

68. The lighting system of claim 42, wherein the first controller or the second controller is further configured to generate a control signal providing that the combination of electrical biasing is an alternation each second dimming cycle of a combination of forward current pulse modulation and analog regulation of forward current with any arbitrary waveform having an average DC component.

69. The lighting system of claim 42, wherein the combination of the first electrical biasing and second electrical biasing or the combination of the third electrical biasing and fourth electrical biasing is a superposition of an AC signal on a DC signal to control the wavelength emission.

70. The lighting system of claim 42, wherein the first controller and the second controller are further configured to control wavelength emission to a selected variance subject to selected intensity levels over the predetermined range of temperatures.

71. The lighting system of claim 42, wherein the first controller and the second controller are further configured to maintain wavelength emission substantially constant over the predetermined range of temperatures.

72. The lighting system of claim 42, wherein the first and second controllers are further configured to synchronize the combination of electrical biasing respectively with a switching cycle of the first and second driver circuit.

73. The lighting system of claim 72, wherein the combination of the first electrical biasing and second electrical biasing has a duty cycle and an average current level which are related to the selected intensity level according to a first relation of

74. The lighting system of claim 42, wherein each of the first controller and the second controller further comprises:

a block of operational signal registers.

75. The lighting system of claim 74, wherein each of the first controller and the second controller is further configured to program the block of operational signal registers with at least two peak current amplitude values, at least two current amplitude modulation values, and two current duty cycle values to provide an input operational control signal to the first driver circuit to provide the combination of the first electrical biasing and the second electrical biasing for the selected intensity level and emission wavelength control specified by the user interface.

76. The lighting system of claim 75, wherein each of the first controller and the second controller is further configured to vary the intensity of one or more substantially similar light emitting diodes without substantial optical output flickering by alternatively multiplexing the input operational control signal to the first driver circuit from a first set of operational signal registers synchronously to an end of a current dimming frame counter while programming asynchronously a second set of operational signal registers with a second input operational control signal.

77. The lighting system of claim 42, wherein each of the first controller and the second controller is further configured to queue the second input operational control signal to a current status at the end of the current dimming frame counter.

78. The lighting system of claim 42, wherein the user interface is couplable to a microprocessor or a network using a proprietary or standard interface protocol including DMX 512, DALI, I²C, or SPI.

79. The lighting system of claim 42, wherein the power converter of each of the first driver circuit and the second driver circuit is a linear circuit, a switching DC/DC circuit, or a switching AC/DC circuit with a power factor correction circuit.

80. The lighting system of claim 42, wherein each of the first power converter and the second power converter is configured to provide a time averaged modulation of forward current conforming to the corresponding input control signals to vary corresponding intensity by implementing the corresponding combined electrical biasing while maintaining the wavelength emission shift substantially close to zero.

81. The lighting system of claim 42, wherein the plurality of light emitting diodes further comprises:

one or more third light emitting diodes connected in a third channel and having a third spectrum different from the first and second spectra, a fifth electrical biasing for the one or more third light emitting diodes producing a fifth wavelength shift, and a sixth electrical biasing for the one or more third light emitting diodes producing a sixth wavelength shift opposing the fifth wavelength shift;

a third driver circuit coupled to the one or more third light emitting diodes, wherein the third driver circuit includes a third regulator and a third power converter, and wherein the third driver circuit is configured to respond to a third plurality of input operational signals to provide a third combination of the fifth electrical biasing and the sixth electrical biasing to the one or more third light emitting diodes; and

a third controller couplable to the user interface and coupled to the third driver circuit, wherein the third controller includes a third memory, wherein the third controller is configured to retrieve a third plurality of parameters stored in the third memory, wherein the third plurality of parameters corresponds to a third intensity level provided by the user interface and designates the third combination of the fifth electrical biasing and the sixth electrical biasing, and wherein the third controller is further configured to convert the third plurality of parameters into a third input operational control signal to provide the third intensity level of the one or more third light emitting diodes with wavelength emission control.

82. The lighting system of claim 81, wherein the one or more first light emitting diodes comprises a plurality of red light emitting diodes, the one or more second light emitting diodes comprises a plurality of green light emitting diodes, and the one or more third light emitting diodes comprises a plurality of blue light emitting diodes.

83. The lighting system of claim 82, further comprising:

an electrodynamic cooling element coupled to a heat sink of the one or more first light emitting diodes;

a temperature sensor coupled to the one or more first light emitting diodes and to the first controller;

a junction temperature regulator coupled to the temperature sensor and to a reference voltage source configured to provide a set temperature signal; and

a buffer coupled to an output of the junction temperature regulator and configured to provide a DC current to the electrodynamic cooling element to regulate a junction temperature of the one or more first light emitting diodes.

84. The lighting system of claim 83, wherein the junction temperature regulator is further coupled to the first controller to decrease the first intensity when the junction temperature is above a set value.