Systems and methods for controlling color temperature

• US 10,420,185 B2
• Filed: 12/05/2017
• Issued: 09/17/2019
• Est. Priority Date: 12/05/2016
• Status: Active Grant

• Current Assignee: Lutron Technology Company LLC
• Original Assignee: Lutron Technology Company LLC
• Inventors: Biery, Ethan Charles, Casey, Craig Alan, Chitta, Venkatesh, Protzman, Brent, Shearer, Thomas M., Taipale, Mark S.
• Primary Examiner(s): Vu, Jimmy T
• Assistant Examiner(s): Yesildag, Laura
• Application Number:
  US15/832,716
• Publication Number:
  US 20180160491A1
• Time in Patent Office: 651 Days
• CPC Class Codes: H05B 45/20 Controlling the colour of the light
• CPC Class Codes: H05B 45/22 using optical feedback
• CPC Class Codes: H05B 47/19 via wireless transmission

Abstract

Methods and systems may be used for controlling the color temperature of one or more light sources (e.g., discrete-spectrum light sources) based on fixture capability information. Fixture capability information may be obtained using a configuration tool. The fixture capability information may be determined by the configuration tool, and the fixture capability information determined by the configuration tool may be stored and/or processed. The fixture may have a memory for storing the fixture capability information. The fixture capability information may also be stored in a remote network device. A system controller may obtain the fixture capability information from the fixture or the remote control device. The system controller may generate control instructions based on the fixture capability information and send the control instructions to the fixtures.

Claims

1. A system controller for a load control system having a plurality of lighting fixtures in a space, the system controller comprising:

a communication circuit configured to transmit and receive messages;

a memory for storing fixture capability information associated with one or more of the plurality of lighting fixtures located in the space; and

a control circuit configured to;

receive the fixture capability information for the plurality of lighting fixtures via the communication circuit,

wherein the fixture capability information comprises at least a first color temperature range associated with a color temperature for a first lighting fixture of the plurality of lighting fixtures and a second color temperature range associated with a color temperature for a second lighting fixture of the plurality of lighting fixtures,

wherein each of the first color temperature range and the second color temperature range comprise a respective color temperature range between a warm-white color temperature and a respective cool-white color temperature;

compare the first color temperature range with the second color temperature range;

determine a third color temperature range that is common to the first color temperature range associated with the first lighting fixture and the second color temperature range associated with the second lighting fixture,

wherein the determined third color temperature range comprises a maximum warm-white color temperature that is common to the first color temperature range and the second color temperature range,

and wherein the third color temperature range comprises a minimum cool-white color temperature that is common to the first color temperature range and the second color temperature range, and

update the respective color temperature range of each of the first lighting fixture and the second lighting fixture such that control of each of the first lighting fixture and second lighting fixture is limited within the maximum warm-white color temperature and the minimum cool-white color temperature of the third color temperature range that is common to the first color temperature range associated with the first lighting fixture and the second color temperature range associated with the second lighting fixture.

2. The system controller of claim 1, wherein the third color temperature range is a room color temperature range for the plurality of lighting fixtures located in the space.

3. The system controller of claim 2, wherein the control circuit is configured to determine the room color temperature range by identifying the maximum warm-white color temperature of warm-white color temperatures of the first color temperature range and the second color temperature range, identifying the minimum cool-white color temperature of cool-white color temperatures of the first color temperature range and the second color temperature range, and setting the room color temperature range to be between the identified maximum warm-white color temperature and the identified minimum cool-white color temperature.

4. The system controller of claim 2, wherein the control circuit is configured to determine the room color temperature range by identifying a maximum warm-white color temperature at which colors of a cumulative light emitted by the respective first lighting fixture and second lighting fixture is within a first MacAdam ellipse of each other, identifying a minimum cool-white color temperature at which the colors of the cumulative light emitted by the respective first lighting fixture and second lighting fixture is within a second MacAdam ellipse of each other, and setting the room color temperature range to be between the identified maximum warm-white color temperature and the identified minimum cool-white color temperature.

5. The system controller of claim 2, wherein the control circuit is configured to generate control instructions for at least one of the first lighting fixture or the second lighting fixture to limit the first lighting fixture and the second lighting fixture to operate within the room color temperature range, and transmit a message including the generated control instructions to the at least one of the first lighting fixture or the second lighting fixture.

6. The system controller of claim 1, wherein the control circuit is configured to determine a room color gamut for the plurality of lighting fixtures located in the space.

7. The system controller of claim 6, wherein the first lighting fixture and the second lighting fixture are each associated with a respective color gamut, the control circuit configured to determine the room color gamut by identifying an overlapping gamut of the color gamuts of the first lighting fixture and the second lighting fixture, and setting the room color gamut to be relatively equal to the identified overlapping gamut.

8. The system controller of claim 6, wherein the control circuit is configured to generate control instructions for at least one of the first lighting fixture or the second lighting fixture to limit the first lighting fixture and the second lighting fixture to operate within the room color gamut, and transmit a message including the generated control instructions to the at least one of the first lighting fixture or the second lighting fixture.

9. The system controller of claim 6, wherein the control circuit is configured to adjust a color mixing curve to fit within the room color gamut.

10. The system controller of claim 6, wherein the control circuit is configured to store chromaticity coordinates of corners of the room color gamut in the fixture capability information in the memory.

11. The system controller of claim 1, wherein the control circuit is configured to determine a room color mixing curve for the plurality of lighting fixtures located in the space.

12. The system controller of claim 11, wherein the control circuit is configured to receive a static color temperature of at least one of the plurality of lighting fixtures, and set the room color mixing curve to be constant at the static color temperature.

13. The system controller of claim 11, wherein the control circuit is configured to receive a fixed color mixing curve of at least one of the plurality of lighting fixtures, and set the room color mixing curve to be relatively equal to the fixed color mixing curve.

14. The system controller of claim 11, wherein the control circuit is configured to set the room color mixing curve to be relatively equal to a desired color mixing curve if there are no unconfigurable lighting fixtures in the space.

15. The system controller of claim 1, wherein the control circuit is configured to transmit a request for the fixture capability information of the plurality of lighting fixtures via the communication circuit prior to receiving the fixture capability information.

16. The system controller of claim 15, wherein the control circuit is configured to receive the fixture capability information from a remote network device via the communication circuit.

17. The system controller of claim 16, wherein the control circuit is configured to obtain an identifier of at least one lighting fixture of the plurality of lighting fixtures prior to transmitting the request for the fixture capability information of the at least one lighting fixture.

18. The system controller of claim 15, wherein the control circuit is configured to receive the fixture capability information from each of the lighting fixtures via the communication circuit.

19. The system controller of claim 15, wherein the control circuit is configured to receive the fixture capability information from at least one measurement sensor that is configured to measure an operating characteristic of light emitted by the plurality of lighting fixtures.

20. The system controller of claim 1, wherein the control circuit is configured to generate control instructions for at least one of the first lighting fixture or the second lighting fixture based on the determined third color temperature range, and transmit a message including the generated control instructions to the at least one of the first lighting fixture or the second lighting fixture via the communication circuit.

21. A method for a load control system having at least one system controller, the method comprising:

receiving and storing fixture capability information for a plurality of lighting fixtures in a space, wherein the fixture capability information comprises at least a first color temperature range associated with a color temperature for a first lighting fixture of the plurality of lighting fixtures and a second color temperature range associated with a color temperature for a second lighting fixture of the plurality of lighting fixtures

wherein each of the first color temperature range and the second color temperature range comprise a respective color temperature range between a respective warm-white color temperature and a respective cool-white color temperature;

comparing, via at least one apparatus in the load control system, the first color temperature range with the second color temperature range;

determining, via at least one apparatus in the load control system, a third color temperature range that is common to the first color temperature range associated with the first lighting fixture and the second color temperature range associated with the second lighting fixture,

wherein the determined third color temperature range comprises a maximum warm-white color temperature that is common to the first color temperature range and the second color temperature range, and

wherein the third color temperature range comprises a minimum cool-white color temperature that is common to the first color temperature range and the second color temperature range; and

updating, via at least one apparatus in the load control system, the respective color temperature range of each of the first lighting fixture and the second lighting fixture such that control of each of the first lighting fixture and the second lighting fixture is limited within the maximum warm-white color temperature and the minimum cool-white color temperature of the third color temperature range that is common to the first color temperature range associated with the first lighting fixture and the second color temperature range associated with the second lighting fixture.