Method and apparatus for achieving perceived light mixing via alternating different colored LEDS

• US 7,586,273 B2
• Filed: 02/09/2007
• Issued: 09/08/2009
• Est. Priority Date: 02/09/2006
• Status: Active Grant

• Current Assignee: Dialight Corporation (Dialight PLC)
• Original Assignee: Dialight Corporation (Dialight PLC)
• Inventors: Curran, John W.
• Primary Examiner(s): Vu; David Hung
• Assistant Examiner(s): Le; Tung X
• Application Number:
  US11/673,294
• Publication Number:
  US 20070183161A1
• Time in Patent Office: 942 Days
• Field of Search: 315/246, 315/247, 315/291, 315/294, 315/307, 315/360, 315/363, 315/308, 315/312, 362/458
• US Class Current: 315/291
• CPC Class Codes: F21S 10/02 changing colors F21S10/002 - F21S10/007, F21S10/04 take precedence
• CPC Class Codes: F21V 23/04 the elements being switches safety devices F21V25/00
• CPC Class Codes: F21W 2131/406 for theatres, stages or film studios
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]

Abstract

A method and apparatus for achieving perceived light mixing via alternating colored light emitting diodes (LEDs) is disclosed. For example, a control signal to produce a requested color output is received. Then a timing sequence for at least two different colored LEDs to achieve the requested color output is determined. Then the at least two different colored LEDs are activated in an alternating fashion such that the requested color output is observed.

Claims

1. A light apparatus, comprising:

a master controller for receiving a control signal requesting a color output and determining a timing sequence to achieve said requested color output;

a pulse controller coupled to said master controller; and

a driver coupled to said pulse controller and at least two different colored light emitting diodes (LEDs), wherein said at least two different colored LEDs are activated in an alternating fashion in accordance with a frequency of said timing sequence such that only one of said at least two different colored LEDs is powered on at a time such that a receptive sensor perceives the requested color output.

2. The light apparatus of claim 1, comprising:

a multiplexer coupled to said driver and said at least two different colored LEDs such that said driver activates only one of said two different colored LEDs at a time.

3. The light apparatus of claim 1, comprising:

a memory coupled to said master controller for storing timing sequences.

4. The light apparatus of claim 1, comprising:

a timing controller coupled to said master controller for providing a clock reference to said master controller.

5. The light apparatus of claim 1, wherein said predetermined frequency is at least 100 hertz.

6. The light apparatus of claim 1, comprising:

at least one additional LED coupled to said driver, wherein said at least one additional LED is a different color than each one of said at least two different colored LEDs.

7. The light apparatus of claim 1, wherein said pulse controller controls an illumination interval and an illumination level of an activated one of said at least two different colored LEDs.

8. The light apparatus of claim 1, wherein said receptive sensor comprises a mechanical sensor.

9. The light apparatus of claim 1, wherein said receptive sensor comprises a human eye.

10. A method of achieving a perception of a desired color output using at least two different colored light emitting diodes (LEDs), comprising:

receiving a control signal to produce a requested color output;

determining a timing sequence of said at least two different colored LEDs to achieve said requested color output;

activating a first one of said at least two different colored LEDs to output a first color;

deactivating said first one of said at least two different colored LEDs; and

activating a second one of said at least two different colored LEDs to output a second color after deactivating said first one of said at least two different colored LEDs in accordance with a frequency of said timing sequence such that said requested color output is observed and such that only one of said at least two different colored LEDs is powered on at a time such that a receptive sensor perceives said requested color output.

11. The method of claim 10, comprising:

deactivating said second one of said at least two different colored LEDs;

activating said first one of said at least two different colored LEDs to output said first color after deactivating said second one of said at least two different colored LEDs in accordance with said frequency of said timing sequence such that said requested color output is observed; and

repeating all of said activating and deactivating steps for a desired duration according to said timing sequence.

12. The method of claim 10, comprising

deactivating said second one of said at least two different colored LEDs;

activating at least one additional LED to output a third color after deactivating said second one of said at least two different colored LEDs in accordance with said frequency of said timing sequence such that said requested color output is observed, wherein said at least one additional LED is a different color than each one of said at least two different colored LEDs; and

repeating all of said activating and deactivating steps for a desired duration according to said timing sequence.

13. The method of claim 10, wherein said frequency is selected such that all of said activation and deactivation steps are indistinguishable to a human visual system and appear to be continuously illuminated.

14. The method of claim 10, wherein said frequency is at least 100 hertz.

15. The method of claim 10, wherein said first and second color outputs are directed in the same direction such that at least a portion of said first color output overlaps a portion of space that will be occupied by at least a portion of said second color output when said second LED is activated.

16. The method of claim 10, wherein activating said first one of said at least two different colored LEDs comprises a first illumination interval and a first illumination level and activating said second one of said at least two different colored LEDs comprises a second illumination interval and a second illumination level.

17. The method of claim 16, comprising an illumination period, wherein said illumination period is a sum of said first and second illumination intervals.

18. The method of claim 16, wherein said first and second color outputs may be adjusted such that said requested color output is observed by adjusting any combination of said first and second illumination intervals and illumination levels.

19. A method of achieving a perception of a desired color output using at least two different colored light emitting diodes (LEDs), comprising:

receiving a control signal to produce a requested color output;

determining a timing sequence of said at least two different colored LEDs to achieve said requested color output; and

activating said at least two different colored LEDs in an alternating fashion in accordance with a frequency of said timing sequence to output two different colors in a same direction, such that each one of said at least two different colored LEDs are never activated simultaneously and said requested color output is observed.

20. The method of claim 19, comprising:

activating at least one additional LED with said at least two different colored LEDs in an alternating fashion within a frequency in accordance with said timing sequence, wherein said at least one additional LED is a different color than each one of said at least two different colored LEDs.