Chaotic approach to control of lighting

1. A lighting system, comprising:

first and second lighting devices each comprising at least one controllable source of visible light configured to illuminate a space to be utilized by one or more biological occupants; and

at least one controller coupled to control operation of the at least one source of visible light of each of the first and second lighting devices,

wherein the at least one controller is configured to control operation of the sources of visible light of the first and second lighting devices so as to vary a characteristic of visible light emitted from the lighting devices into the space over a period of time at least in part in accordance with a chaotic function.

2. The lighting system of claim 1 , wherein the at least one controller is configured to vary the operation of the sources of visible light of the first and second lighting devices in such a manner that the characteristic of the visible light emitted from the lighting devices into the space varies over the period of time at least in part in accordance with the chaotic function, so as to effect perception by the one or more occupants in a manner that promotes an objective purpose of the space when occupied.

3. The lighting system of claim 1 , wherein the sources of both the first and second lighting devices are controlled at least in part in accordance with the same chaotic function.

4. The lighting system of claim 3 , wherein the sources of the first and second lighting devices are controlled at least in part based on the same chaotic function in an in-phase manner relative to each other.

5. The lighting system of claim 3 , wherein the sources of the first and second lighting devices are controlled at least in part based on the same chaotic function in an out-of-phase manner relative to each other.

6. The lighting system of claim 3 , further comprising:

a network, wherein:

the at least one controller comprises a first controller in the first lighting device coupled to control the at least one controllable source of visible light in the first lighting device and a second controller in the second lighting device coupled to control the at least one controllable source of visible light in the second lighting device;

each of the lighting devices further comprises a communication interface configured to enable communication of the respective first or second controller via the network; and

the communications via the network facilitate the control operations of the sources in the first and second lighting devices to vary the characteristic of visible light emitted by the lighting devices into the space over the period of time at least in part in accordance with the chaotic function.

7. The lighting system of claim 3 , wherein the characteristic of visible light that varies is a light characteristic selected from the group consisting of: intensity of light, spectral content of light, polarization of light, color temperature of light, and chromaticity difference (Delta_uv) of light from the Planckian locus.

8. The lighting system of claim 1 , wherein the characteristic of visible light that varies is intensity of light flux of visible light emitted from the lighting devices into the space.

9. The lighting system of claim 1 , wherein the characteristic of visible light that varies is a color characteristics of visible light emitted from the lighting devices into the space selected from the group consisting of: spectral content of light, color temperature of light, and chromaticity difference (Delta_uv) of light from the Planckian locus.

10. The lighting system of claim 1 , wherein the at least one controller is further configured to limit extent of the variation of the characteristic of visible light emitted from the lighting devices into the space over the period of time in accordance with the chaotic function to less than or equal to a predetermined maximum amount.

11. The lighting system of claim 1 , wherein the at least one controller is further configured to limit rate of the variation of the characteristic of visible light emitted from the lighting devices into the space over the period of time in accordance with the chaotic function to less than or equal to a predetermined maximum rate.

12. The lighting system of claim 1 , wherein the at least one controller is configured to control operation of the sources of the first and second lighting devices so that the characteristic of the visible light emitted from the lighting devices into the space varies over the period of time in accordance with a combination of a nominal function and the chaotic function.

13. The lighting system of claim 12 , wherein the combination of the nominal function and the chaotic function approximates a natural variation of the characteristic for visible light.

14. The lighting system of claim 12 , wherein the nominal function is a set level for the characteristic of the visible light emitted from the lighting devices into the space.

15. The lighting system of claim 12 , wherein the nominal function comprises a combination of a set level for the characteristic of the visible light emitted from the lighting devices into the space and a variable function.

16. The lighting system of claim 1 , wherein the at least one controller is further configured to control operation of the sources of visible light of the first and second lighting devices so that the characteristic of the visible light emitted into the space varies in accordance with the chaotic function in a state that is unstable with attractors.

17. The lighting system of claim 1 , wherein the chaotic function comprises a mathematical expression that determines the variation of the characteristic of the visible light emitted into the space in a dynamic manner that appears random or lacking in order.

18. The lighting system of claim 17 , wherein the expression is dynamic and highly sensitive to an initial condition.

19. A lighting device, comprising:

a controllable source of visible light configured to illuminate a space to be utilized by one or more biological occupants; and

a controller coupled to the source of visible light,

wherein the controller is configured to control operation of the source of visible light, including control of a characteristic of visible light emitted from the source into the space over a period of time in accordance with a combination of a nominal function and a chaotic function.

20. The lighting device of claim 19 , wherein the controller is configured, to vary the operation of the source of visible light in such a manner that the characteristic of the visible light emitted from the source into the space varies over the period of time at least in part in accordance with the chaotic function, so as to effect perception by the one or more occupants in a manner that promotes an objective purpose of the space when occupied.

21. The lighting device of claim 19 , wherein the controller is configured, to vary the operation of the source of visible light in such a manner that the characteristic of the visible light emitted from the source into the space varies over the period of time at least in part in accordance with the chaotic function, so as to effect perception by the one or more occupants in a manner that promotes a positive objective impact on an occupant of the space.

22. The lighting device of claim 19 , wherein the controller is configured, to vary the operation of the source of visible light in such a manner that the characteristic of the visible light emitted from the source into the space varies over the period of time at least in part in accordance with the chaotic function, so as to effect perception by the one or more occupants in a manner that promotes a negative objective impact of lighting on an occupant of the space.

23. The lighting device of claim 22 , wherein the variation of the characteristic of the visible light emitted from the source into the space is intended to encourage the occupant to leave the space.

24. The lighting device of claim 22 , wherein the variation of the characteristic of the visible light emitted from the source into the space is intended to impair the occupant's perception while in the space.

25. The lighting device of claim 19 , wherein the combination of the nominal function and the chaotic function approximates a natural variation of the characteristic for visible light.

26. The lighting device of claim 19 , wherein the nominal function is a set level for the characteristic of the visible light emitted from the lighting devices into the space.

27. The lighting device of claim 19 , wherein the nominal function comprises a combination of a set level for the characteristic of the visible light emitted from the lighting devices into the space and a variable function.

28. A lighting device, comprising:

a controllable source of visible light configured to illuminate a space to be utilized by one or more biological occupants; and

a controller coupled to the source of visible light,

wherein the controller is configured to control operation of the source of visible light, including control of a characteristic of visible light emitted from the source into the space over a period of time in accordance with a chaotic function, so as to effect perception by the one or more occupants in a manner that promotes a negative objective impact of lighting on an occupant of the space.

29. The lighting device of claim 28 , wherein the variation of the characteristic of the visible light emitted from the source into the space is intended to encourage the occupant to leave the space.

30. The lighting device of claim 28 , wherein the variation of the characteristic of the visible light emitted from the source into the space is intended to impair the occupant's perception while in the space.