CHAOTIC APPROACH TO CONTROL OF LIGHTING

• US 20140055041A1
• Filed: 08/24/2012
• Published: 02/27/2014
• Est. Priority Date: 08/24/2012
• Status: Active Grant

• Current Assignee: ABL IP Holding LLC (Acuity Brands, Inc.)
• Original Assignee: ABL IP Holding LLC (Acuity Brands, Inc.)
• Inventors: Ramer, David P., Rains, Jack C. Jr.
• Granted Patent: US 8,779,669 B2
• Time in Patent Office: Days
• US Class Current: 315/153
• CPC Class Codes: H05B 45/20 Controlling the colour of the light
• CPC Class Codes: H05B 47/10 Controlling the light source
• CPC Class Codes: H05B 47/11 by determining the brightness or colour temperature of ambient light
• CPC Class Codes: H05B 47/155 Coordinated control of two or more light sources
• CPC Class Codes: H05B 47/175 by remote control
• CPC Class Codes: Y02B 20/40 Control techniques providing energy savings, e.g. smart controller or presence detection

Abstract

At least one controllable source of visible light is configured to illuminate a space to be utilized by one or more occupants. A controller causes the source(s) to emit light in a manner that varies at least one characteristic of visible light emitted into the space over a period of time at least in part in accordance with a chaotic function.

Claims

1. A lighting device, 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 the at least one source of visible light, wherein the at least one controller is configured to control operation of the at least one source of visible light so as to vary at least one characteristic of visible light emitted from the at least one source into the space over a period of time at least in part in accordance with a chaotic function.

2. The lighting device of claim 1, wherein the at least one controller is configured, to vary the operation of the at least one source of visible light in such a manner that the at least one characteristic of the visible light emitted from the at least one 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.

3. The lighting device of claim 1, wherein the lighting device is a single light fixture including the at least one source of visible light and the at least one controller.

4. A system comprising a plurality of the lighting devices of claim 1, wherein the controllers in the lighting devices are configured to control operations of the sources in the lighting devices in a coordinated manner to vary the at least one characteristic of total visible light emitted by the sources into the space over the period of time at least in part in accordance with the chaotic function.

5. The system of claim 4, further comprising:

a network, wherein;

each of the lighting devices further comprises a communication interface configured to enable communication via the network; and

the communications via the network facilitates the control operations of the sources in the lighting devices in said coordinated manner to vary the at least one characteristic of total visible light emitted by the sources into the space over the period of time at least in part in accordance with the chaotic function.

6. The lighting device of claim 1, wherein the at least one characteristic of visible light that varies includes one or more light characteristics 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.

7. The lighting device of claim 1, wherein the at least one characteristic of visible light that varies comprises intensity of light and at least one color characteristic of light.

8. The lighting device of claim 7, wherein the at least one color characteristic of light includes one or more color characteristics 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.

9. The lighting device of claim 1, wherein:

the at least one source of visible light comprises at least one first source configured to emit visible light of a first color characteristic and at least one second source configured to emit visible light of a second color characteristic different from the first color characteristic, and

the at least one controller is configured to control the first and second sources to vary a color characteristic of combined visible light emitted by the sources into the space over the period of time at least in part in accordance with the chaotic function.

10. The lighting device of claim 9, wherein the varied color characteristic of combined visible light emitted by the sources into the space is a color characteristic 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.

11. The lighting device of claim 1, wherein the at least one controller is further configured to limit extent of the variation in accordance with the chaotic function to less than or equal to a predetermined maximum amount.

12. The lighting device of claim 1, wherein the at least one controller is further configured to limit rate of the variation in accordance with the chaotic function to less than or equal to a predetermined maximum rate.

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

14. The lighting device of claim 12, wherein the combination of the nominal function and the chaotic function approximates a natural variation of at least one characteristic of visible light.

15. The lighting device of claim 1, wherein the at least one controller is further configured to control operation of the at least one source of visible light so that the at least one characteristic of the visible light varies in accordance with the chaotic function in a state that is unstable with attractors.

16. A method, comprising steps of:

operating an electrically driven source to emit visible light, to illuminate a space to be utilized by one or more biological occupants; and

controlling a variation of at least one characteristic of the visible light emitted from the source over a period of time at least in part in accordance with a chaotic function.

17. The method of claim 16, wherein the variation in accordance with the chaotic function is configured to effect perception by the one or more occupants in a manner that promotes an objective purpose of the space when occupied.

18. The method of claim 16, wherein a coefficient of the chaotic function has a value that configures the chaotic function in a state that is unstable with attractors, for at least part of the period of time.

19. The method of claim 16, wherein the controlling step comprises varying the at least one characteristic of the visible light from the source in accordance with a combination of a nominal function over the period of time and the chaotic function.

20. The method of claim 19, wherein the combination of the nominal function and the chaotic function approximates a natural variation of at least one characteristic of visible light.

21. The method of claim 16, further comprising:

sensing a characteristic of ambient light in the space,

wherein the controlling of the variation of at least one characteristic of the visible light emitted from the source is at least partially responsive to the sensed characteristic of ambient light in the space.

22. An article of manufacture, comprising a non-transitory machine readable medium and instructions embodied in the medium for configuring a programmable controller of a lighting device to implement the method of claim 16.