Adaptive anti-glare light system and associated methods

• US 8,901,850 B2
• Filed: 03/11/2013
• Issued: 12/02/2014
• Est. Priority Date: 05/06/2012
• Status: Active Grant

• Current Assignee: Lighting Science Group Corporation (Pegasus Capital Advisors, L.P.)
• Original Assignee: Lighting Science Group Corporation (Pegasus Capital Advisors, L.P.)
• Inventors: Maxik, Frederic S., Soler, Robert R., Bartine, David E.
• Primary Examiner(s): Tran, Thienvu
• Assistant Examiner(s): LO, CHRISTOPHER KWOK YEUNG
• Application Number:
  US13/792,354
• Publication Number:
  US 20130293150A1
• Time in Patent Office: 631 Days
• Field of Search: 315/82, 315/151, 315154-159, 315/291, 315/307, 315/297, 362/84, 362/231, 362/276, 362/802, 362/249.02, 362/431, 345/426, 345/428, 345/589, 345/204, 345/207, 345/211, 345/214, 345690-691, 345/22, 345 45- 46, 345/48, 345 63- 64, 345 76- 77, 345/84
• US Class Current: 315/297
• CPC Class Codes: H05B 45/20 Controlling the colour of the light
• CPC Class Codes: H05B 47/19 via wireless transmission
• CPC Class Codes: H05B 47/1965 using handheld communication devices

Abstract

An adaptive anti-glare light system including a sensor, a color selection engine, a controller, and a plurality of light sources each configured to emit a source light. The sensor transmits a source color signal designating a reflected light characterized by a detected color and a discomfort glare rating. The color selection engine determines a dominant wavelength of the detected color, and a combination of the light sources that the controller may operate to emit a combined wavelength that matches the dominant wavelength of the detected color. A method of adapting light as a countermeasure to glare comprises receiving the detected color, determining a subset of the plurality of light sources that may be combined to form an adapted light that matches the detected color, and operating the light sources with a white light to emit the adapted light at or above a threshold discomfort glare level.

Claims

1. A method of adapting light to environmental conditions as a countermeasure to glare using a lighting device that includes a sensor, a color selection engine operatively coupled to the sensor, a controller operatively coupled to the color selection engine, and a plurality of light sources each configured to emit a source light in a source wavelength range, wherein each of the plurality of light sources is operatively coupled to the controller, wherein at least one of the plurality of light sources is a white light, the method comprising:

emitting a first light;

receiving a reflected light comprising a detected color;

determining if the detected color is characterized by a discomfort glare rating below a threshold level;

determining a dominant wavelength of the detected color that is characterized by the discomfort glare rating of the detected color being below the threshold value;

determining a combination of at least two of the plurality of light sources that emit a combined wavelength that approximately matches the dominant wavelength of the detected color; and

operating the combination of at least two of the plurality of light sources to emit the combined wavelength to be defined as an adapted light that has a discomfort rating at or above the threshold value, wherein at least one of the plurality of light sources is the white light.

2. The method according to claim 1 further comprising the steps of:

determining an illuminance of the detected color; and

operating the combination of at least two of the plurality of light sources such that the adapted light has an illuminance approximately equal to the determined illuminance of the detected color.

3. The method according to claim 1 wherein the threshold value is a discomfort glare rating of less than 6 on the De Boer scale.

4. The method according to claim 3 wherein operating the combination of at least two of the plurality of light sources to emit the combined wavelength further comprises altering the adapted light to a new combined wavelength selected in the range between the combined wavelength and 577 nm.

5. The method according to claim 1 wherein at least one of the plurality of light sources comprises a light emitting diode (LED).

6. The method according to claim 1 wherein the lighting device further comprises a conversion engine;

wherein the color selection engine is operatively coupled to the conversion engine; and

wherein detecting the detected color further comprises;

monitoring for the detected color within a desired illumination range that is based on at least one of a constant, a controlled vehicle speed, an ambient light level, a weather condition, a presence of a vehicle, an absence of a vehicle, and a type of roadway;

receiving a source color signal designating the detected color;

determining RGB values of the detected color;

converting the RGB values of the detected color to XYZ tristimulus values.

7. The method according to claim 6 wherein the dominant wavelength of the detected color is defined as a boundary intersect value within a color space that is collinear with the XYZ tristimulus values of the detected color and the XYZ tristimulus values of a white point, such that the boundary intersect value is closer to the XYZ tristimulus values of the detected color than to the XYZ tristimulus values of the white point.

8. The method according to claim 7 wherein determining the combination of the at least two of the plurality of light sources further comprises identifying a subset of colors within the source wavelength ranges of the source lights emitted by the plurality of light sources such that the subset of colors combine to match the dominant wavelength of the detected color;

and choosing two or more of the subset of colors to combine to match the dominant wavelength of the detected color to include a first color of a source wavelength defined as a first color value and a second color of a source wavelength defined as a second color value.

9. The method according to claim 8 wherein the first color value is greater than the dominant wavelength of the detected color;

wherein the second value is lesser than the dominant wavelength of the detected color; and

wherein none of the remaining subset of colors has a source wavelength nearer to the dominant wavelength of the detected color than either of the first color value and the second color value.

10. The method according to claim 8 wherein the first color value is lesser than the dominant wavelength of the detected color;

and wherein none of the subset of colors has a source wavelength greater than the first color value, and none of the subset of colors has a source wavelength lesser than a source wavelength of the second color value.

11. The method according to claim 8 wherein the second color value is greater than the dominant wavelength of the detected color;

and wherein none of the subset of colors has a source wavelength lesser than the second color value, and none of the subset of colors has a source wavelength greater than a source wavelength of the first color value.

12. The method according to claim 8 wherein choosing two or more of the subset of colors to combine to match the dominant wavelength of the detected color further comprises:

defining a color line containing the XYZ tristimulus values of the detected color and the XYZ tristimulus values of the white point;

defining a matching line containing XYZ tristimulus values of the first color and XYZ tristimulus values of the second color; and

identifying an intersection point of the color line and the matching line, defined as an intersection color;

wherein the method further comprises determining a percentage of the first color value and a percentage of the second color value to combine to match the dominant wavelength of the intersection color.

13. An adaptive anti-glare light system to control a lighting device comprising:

a sensor;

a color selection engine operatively coupled to the sensor;

a controller operatively coupled to the color selection engine; and

a plurality of light sources each configured to emit a source light in a source wavelength range, wherein each of the plurality of light sources is operatively coupled to the controller and at least one of the plurality of light sources is a white light;

wherein the sensor is configured to receive a reflected light comprising a detected color;

wherein the color selection engine is configured to perform a matching operation to determine a dominant wavelength of the detected color, and to determine a combination of at least two of the plurality of light sources that emit a combined wavelength that approximately matches the dominant wavelength of the detected color; and

wherein the controller is configured to determine if the detected color is characterized by a discomfort glare rating below a threshold level and to operate the combination of at least two of the plurality of light sources to emit the combined wavelength to be defined as an adapted light that has a discomfort rating at or above the threshold value, wherein at least one of the plurality of light sources is the white light.

14. The system according to claim 13 wherein at least one of the plurality of light sources comprises a light emitting diode (LED).

15. The system according to claim 14 wherein the threshold value is a discomfort glare rating of less than 6 on the De Boer scale.

16. The system according to claim 15 wherein the controller is configured to operate the combination of at least two of the plurality of light sources to emit a new combined wavelength selected in the range of wavelengths between the combined wavelength and 577 nm.

17. The system according to claim 13 further comprising a conversion engine;

wherein the sensor is configured to monitor for the detected color within a desired illumination range that is based on at least one of a constant, a controlled vehicle speed, an ambient light level, a weather condition, a presence of a vehicle, an absence of a vehicle, and a type of roadway;

wherein the conversion engine is configured to perform a conversion operation that receives a source color signal designating the detected color, to determine RGB values of the detected color, and to convert the RGB values of the detected color to XYZ tristimulus values.

18. The system according to claim 17 wherein the dominant wavelength of the detected color is defined as a boundary intersect value within the standardized color space that is collinear with the XYZ tristimulus values of the detected color and XYZ tristimulus values of a white point, and such that the boundary intersect value is closer to the XYZ tristimulus values of the detected color than to the XYZ tristimulus values of the white point.

19. The system according to claim 18 wherein the color selection engine is configured to perform an identifying operation that operates to identify a subset of colors within the source wavelength ranges of the source lights emitted by the plurality of light sources such that the subset of colors combine to match the dominant wavelength of the detected color;

and to perform a choosing operation that operates to choose two or more of the subset of colors to combine to match the dominant wavelength of the detected color to include a first color of a source wavelength defined as a first color value and a second color of a source wavelength defined as a second color value.

20. The system according to claim 19 wherein the first color value is greater than the dominant wavelength of the detected color;

wherein the second value is lesser than the dominant wavelength of the detected color; and

wherein none of the subset of colors has a source wavelength nearer to the dominant wavelength of the detected color than either of the first color value and the second color value.

21. The system according to claim 19 the first color value is lesser than the dominant wavelength of the detected color;

and wherein none of the subset of colors has a source wavelength greater than the first color value, and none of the subset of colors has a source wavelength lesser than the second color value.

22. The system according to claim 19 wherein the second color value is greater than the dominant wavelength of the detected color;

and wherein none of the subset of colors has a source wavelength lesser than the second color value, and none of the subset of colors has a source wavelength greater than a source wavelength of the first color value.

23. The system according to claim 19 wherein the choosing operation further operates to define a color line containing the XYZ tristimulus values of the detected color and the XYZ tristimulus values of white point, to define a matching line containing the XYZ trisimulus values of the first color and the XYZ trisimulus values of the second color, and to identify an intersection point of the color line and the matching line, defined as an intersection color;

wherein the color selection engine is configured to perform a production operation that operates to determine a percentage of the first color value and a percentage of the second color value to combine to match the dominant wavelength of the intersection color.