Illumination and imaging system and method
A system and method are provided for actively illuminating and monitoring a subject, such as a driver of a vehicle. The system includes a video imaging camera orientated to generate images of the subject eye(s). The system also includes first and second light sources offset from each other and operable to illuminate the subject. The system further includes a controller for controlling illumination of the first and second light sources such that when the imaging camera detects sufficient glare, the controller controls the first and second light sources to minimize the glare. This is achieved by turning off the illuminating source causing the glare.
1. An active illumination imaging system for monitoring a subject, said system comprising:
a video imaging camera oriented to generate images of a subject;
a first light source located at a first location and operable for illuminating the subject;
a second light source located at a second location and operable for illuminating the subject; and
a controller for processing the images generated with the video imaging camera during illumination of the subject and controlling operation of the first and second light sources, said controller detecting presence of sufficient glare based on a threshold brightness and controlling activation of the first and second light sources to reduce the glare when the presence of sufficient glare is detected from an eye region of the subject, wherein the controller turns off one of the first and second light sources in response to the detection of sufficient glare to reduce the glare.
2. The system as defined in claim 1 , wherein the subject comprises an eye.
3. The system as defined in claim 2 , wherein the system is employed in a vehicle for monitoring the eye of a driver of the vehicle.
4. The system as defined in claim 1 , wherein the video imaging camera has an imaging axis and the first and second light sources are located on opposite sides of the imaging axis.
5. The system as defined in claim 4 , wherein the first and second light sources are each located at an angle of at least fifteen degrees relative to the imaging axis.
6. The system as defined in claim 1 , wherein the first light source comprises a first plurality of light emitting diodes.
7. The system as defined in claim 6 , wherein the second light source comprises a second plurality of light emitting diodes.
8. The system as defined in claim 1 , wherein the controller controls the first and second light sources to turn on only one of the first and second light sources at a time.
9. The system as defined in claim 1 , wherein the controller alternates activation of the first and second light sources.
10. An active illumination vehicle eye monitoring system for monitoring an eye of a person in a vehicle, said system comprising:
a video imaging camera located on a vehicle and oriented to generate images of a subject eye of a person in the vehicle;
a first light source located on the vehicle and arranged along a first axis for illuminating the eye;
a second light source located on the vehicle and arranged along a second axis offset from the first axis for illuminating the eye; and
a controller for processing the images generated with the video imaging camera during illumination of the subject eye and controlling operation of the first and second light sources, said controller detecting presence of sufficient glare based on a threshold brightness and controlling activation of the first and second light sources to reduce the glare when the presence of sufficient glare is detected from an eye region of the person, wherein the controller turns off one of the first and second light sources in response to the detection of sufficient glare to reduce the glare.
11. The system as defined in claim 10 , wherein the video imaging camera has an imaging axis and the first and second light sources are located on opposite sides of the imaging axis.
12. The system as defined in claim 11 , wherein the first and second light sources are each located at an angle of at least fifteen degrees relative to the imaging axis.
13. The system as defined in claim 10 , wherein the first light source comprises a first plurality of light emitting diodes.
14. The system as defined in claim 13 , wherein the second light source comprises a second plurality of light emitting diodes.
15. The system as defined in claim 10 , wherein the controller controls the first and second light sources to turn only one of the first and second light sources on at a time.
16. The system as defined in claim 10 , wherein the controller alternates activation of the first and second light sources.
17. A method for actively illuminating and monitoring a subject, said method comprising the steps of:
arranging a video imaging camera to generate images of a subject;
arranging a first light source at a first location;
arranging a second light source at a second location;
illuminating the subject with light generated by the first light source;
generating a first image of the subject while the subject is illuminated with light from the first light source;
detecting the presence of sufficient glare based on a threshold brightness; and
controlling the first and second light sources to reduce the light provided by the first light source when sufficient glare is detected from an eye region of the subject, wherein the first light source is controlled to reduce light by turning the first light source off in response to the detection of sufficient glare.
18. The method as defined in claim 17 , wherein the subject comprises an eye.
19. The method as defined in claim 18 , wherein the method is employed for monitoring the eye of a driver of a vehicle.
20. The method as defined in claim 17 , wherein the steps of arranging the video imaging camera, first light source, and second light source comprises arranging the video imaging camera on an imaging axis, arranging the first light source on one side of the imaging axis and arranging the second light source on an opposite side of the imaging axis.
21. The method as defined in claim 20 , wherein the steps of arranging the first and second light sources further comprises arranging the first and second light sources at an angle of at least fifteen degrees relative to the imaging axis.
22. The method as defined in claim 17 , wherein the step of arranging a video imaging camera comprises arranging only a single video imaging camera to generate images of a subject's face that may be illuminated by both the first and second light sources.
23. The system as defined in claim 1 , wherein the video image camera generates images of a subject that may be illuminated by both the first and second light sources.
24. The system as defined in claim 10 , wherein the video image camera generates images of a subject that may be illuminated by both the first and second light sources.