LIGHTING DEVICES AND METHODS FOR LIGHTING

• US 20080309255A1
• Filed: 05/08/2008
• Published: 12/18/2008
• Est. Priority Date: 05/08/2007
• Status: Active Grant

• Current Assignee: IDEAL Industries Lighting, LLC (Ideal Industries Incorporated)
• Original Assignee: Cree Lighting Company (Ideal Industries Incorporated)
• Inventors: Negley, Gerald H., Harris, Michael, Myers, Peter Jay
• Granted Patent: US 8,174,205 B2
• Time in Patent Office: Days
• US Class Current: 315/297
• CPC Class Codes: F21K 9/62 using mixing chambers, e.g. housings with reflective walls
• 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 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

A lighting device comprises groups of solid state light emitters, a sensor and circuitry. If the emitters are illuminated, the sensor is exposed to combined light from the groups, and senses only a portion of the combined light. The circuitry adjusts current applied to at least one of the emitters based on an intensity of the light sensed. Also, a device comprising emitters, a circuit board and a sensor, at least one of the emitters being positioned on the first circuit board and the sensor being spaced from the circuit board. Also, a lighting device comprising emitters, a sensor, and circuitry which adjusts current applied an emitters based on detection by the first sensor, the circuitry comprising a differential amplifier circuit. Also, a lighting device, comprising light emitters and circuitry which adjusts current applied to only some of the emitters based on ambient temperature. Also, methods of lighting.

Claims

1. A lighting device, comprising:

at least first and second groups of solid state light emitters, said first group of solid state light emitters including at least one first group solid state light emitter, said second group of solid state light emitters including at least one second group solid state light emitter;

at least a first sensor, said first sensor being positioned such that if said first group of solid state light emitters and said second group of solid state light emitters are illuminated, said first sensor will be exposed to combined light, said combined light comprising at least a portion of light emitted by said first group of solid state light emitters and at least a portion of light emitted by said second group of solid state light emitters, said first sensor being sensitive to only a portion of said combined light; and

circuitry configured to adjust a current applied to at least a first of said second group of solid state light emitters based on an intensity of said portion of said combined light sensed by said first sensor.

2. A lighting device as recited in claim 1, wherein said first sensor is sensitive to only some visible wavelengths.

3. A lighting device as recited in claim 1, wherein said portion of said combined light, if mixed in the absence of any other light, would have color coordinates on a 1931 CIE Chromaticity Diagram which define a point within an area enclosed by first, second, third, fourth and fifth line segments, the first line segment connecting a first point to a second point, the second line segment connecting the second point to a third point, the third line segment connecting the third point to a fourth point, the fourth line segment connecting the fourth point to a fifth point, and the fifth line segment connecting the fifth point to the first point, the first point having x, y coordinates of 0.32, 0.40, the second point having x, y coordinates of 0.36, 0.48, the third point having x, y coordinates of 0.43, 0.45, the fourth point having x, y coordinates of 0.42, 0.42, and the fifth point having x, y coordinates of 0.36, 0.38.

4. A lighting device as recited in claim 1, wherein said second group of solid state light emitters comprises at least one solid state light emitter which emits light to which said first sensor is not sensitive.

5. A lighting device as recited in claim 4, wherein said second group of solid state light emitters comprises at least one solid state light emitter which emits light having a dominant wavelength in the range of from about 600 nm to about 630 nm.

6. A lighting device as recited in claim 1, wherein said second group of solid state light emitters consists of solid state light emitters which emit light to which said first sensor is not sensitive.

7. A lighting device as recited in claim 6, wherein said second group of solid state light emitters comprises at least one solid state light emitter which emits light having a dominant wavelength in the range of from about 600 nm to about 630 nm.

8. A lighting device as recited in claim 1, wherein said combined light has x, y coordinates on a 1931 CIE Chromaticity Diagram which define a point which is within ten MacAdam ellipses of at least one point on the blackbody locus on a 1931 CIE Chromaticity Diagram.

9. A lighting device as recited in claim 1, wherein said lighting device further comprises:

at least a first circuit board, at least one of said first and second groups of solid state light emitters being positioned on said first circuit board, said first sensor being spaced from said circuit board.

10. A lighting device as recited in claim 9, wherein said circuit board is a metal core printed circuit board.

11. A lighting device as recited in claim 9, wherein said first sensor is mounted on a spacer, said spacer being mounted on said first circuit board.

12. A lighting device as recited in claim 9, wherein said first sensor is spaced from a first plane defined by a first surface of said circuit board.

13. A lighting device as recited in claim 9, wherein said circuitry further comprises a differential amplifier circuit connected to said first sensor.

14. A lighting device as recited in claim 13, wherein said circuitry is further configured to adjust a current applied only to said second group of solid state light emitters based on ambient temperature.

15. A lighting device as recited in claim 1, wherein said circuitry further comprises a differential amplifier circuit connected to said first sensor.

16. A lighting device as recited in claim 1, wherein said circuitry is further configured to adjust a current applied only to said second group of solid state light emitters based on ambient temperature.

17. A lighting device as recited in claim 16, wherein said second group of solid state light emitters comprises at least one solid state light emitter which emits light having a dominant wavelength in the range of from about 600 nm to about 630 nm.

18. A method of lighting, comprising:

illuminating at least first and second groups of solid state light emitters to produce combined light, said first group of solid state light emitters including at least one first group solid state light emitter;

said second group of solid state light emitters including at least one second group solid state light emitter;

sensing only a portion of said combined light; and

adjusting a current applied to at least a first of said second group of solid state light emitters based on an intensity of said portion of said combined light.

19. A method as recited in claim 18, wherein said portion of said combined light, if mixed in the absence of any other light, would have color coordinates on a 1931 CE Chromaticity Diagram which define a point within an area on a 1931 CIE Chromaticity Diagram enclosed by first, second, third, fourth and fifth line segments, the first line segment connecting a first point to a second point, the second line segment connecting the second point to a third point, the third line segment connecting the third point to a fourth point, the fourth line segment connecting the fourth point to a fifth point, and the fifth line segment connecting the fifth point to the first point, the first point having x, y coordinates of 0.32, 0.40, the second point having x, y coordinates of 0.36, 0.48, the third point having x, y coordinates of 0.43, 0.45, the fourth point having x, y coordinates of 0.42, 0.42, and the fifth point having x, y coordinates of 0.36, 0.38.

20. A method as recited in claim 18, wherein said second group of solid state light emitters comprises at least one solid state light emitter which emits light to which said first sensor is not sensitive.

21. A method as recited in claim 20, wherein said second group of solid state light emitters comprises at least one solid state light emitter which emits light having a dominant wavelength in the range of from about 600 nm to about 630 nm.

22. A method as recited in claim 18, wherein said second group of solid state light emitters consists of solid state light emitters which emit light which emits light to which said first sensor is not sensitive.

23. A method as recited in claim 22, wherein said second group of solid state light emitters comprises at least one solid state light emitter which emits light having a dominant wavelength in the range of from about 600 nm to about 630 nm.

24. A method as recited in claim 18, wherein said combined light has x, y coordinates on a 1931 CIE Chromaticity Diagram which define a point which is within ten MacAdam ellipses of at least one point on the blackbody locus on a 1931 CIE Chromaticity Diagram.

25. A method as recited in claim 18, wherein said current applied to at least a first of said second group of solid state light emitters is adjusted also based on ambient temperature.

26. A method as recited in claim 25, wherein said second group of solid state light emitters comprises at least one solid state light emitter which emits light having a dominant wavelength in the range of from about 600 nm to about 630 nm.

27. A lighting device, comprising:

at least first and second groups of solid state light emitters, said first group of solid state light emitters including at least one first group solid state light emitter, said second group of solid state light emitters including at least one second group solid state light emitter;

at least a first circuit board, at least one of said first and second groups of solid state light emitters being positioned on said first circuit board;

at least a first sensor, said first sensor being positioned such that if said first group of solid state light emitters and said second group of solid state light emitters are illuminated, said first sensor will be exposed to at least a portion of light emitted by said first and second groups of solid state light emitters, said first sensor being spaced from said circuit board; and

circuitry configured to adjust a current applied to at least one of said first and second groups of solid state light emitters based on an intensity of light detected by said first sensor.

28. A lighting device as recited in claim 27, wherein said circuit board is a metal core printed circuit board.

29. A lighting device as recited in claim 27, wherein said first sensor is mounted on a spacer, said spacer being mounted on said first circuit board.

30. A lighting device as recited in claim 27, wherein said first sensor is spaced from a first plane defined by a first surface of said circuit board.

31. A lighting device as recited in claim 27, wherein said circuitry comprises a differential amplifier circuit connected to said first sensor.

32. A lighting device, comprising:

at least first and second groups of solid state light emitters, said first group of solid state light emitters including at least one first group solid state light emitter, said second group of solid state light emitters including at least one second group solid state light emitter;

at least a first sensor, said first sensor being positioned such that if said first group of solid state light emitters and said second group of solid state light emitters are illuminated, said first sensor will be exposed to at least a portion of light emitted by said first and second groups of solid state light emitters; and

circuitry configured to adjust a current applied to at least one of said first and second groups of solid state light emitters based on an intensity of light detected by said first sensor, said circuitry comprising a differential amplifier circuit connected to said first sensor.

33. A lighting device, comprising:

at least first and second groups of solid state light emitters, said first group of solid state light emitters including at least one first group solid state light emitter, said second group of solid state light emitters including at least one second group solid state light emitter; and

circuitry configured to adjust a current applied only to said second group of solid state light emitters based on ambient temperature.

34. A lighting device as recited in claim 33, wherein said second group of solid state light emitters comprises at least one solid state light emitter which emits light having a dominant wavelength in the range of from about 600 nm to about 630 nm.

35. A lighting device as recited in claim 33, wherein a mixture of light emitted from said first group of solid state light emitters and light emitted from said second group of solid state light emitters has x, y coordinates on a 1931 CIE Chromaticity Diagram which define a point which is within ten MacAdam ellipses of at least one point on the blackbody locus on a 1931 CIE Chromaticity Diagram.

36. A method of lighting, comprising:

illuminating at least first and second groups of solid state light emitters, said first group of solid state light emitters including at least one first group solid state light emitter, said second group of solid state light emitters including at least one second group solid state light emitter;

adjusting a current applied only to said second group of solid state light emitters based on ambient temperature.

37. A method as recited in claim 36, wherein said second group of solid state light emitters comprises at least one solid state light emitter which emits light having a dominant wavelength in the range of from about 600 nm to about 630 nm.

38. A method as recited in claim 36, wherein a mixture of light emitted from said first group of solid state light emitters and light emitted from said second group of solid state light emitters has x, y coordinates on a 1931 CIE Chromaticity Diagram which define a point which is within ten MacAdam ellipses of at least one point on the blackbody locus on a 1931 CIE Chromaticity Diagram.