Road lighting
Systems, devices, and methods are disclosed in which one or more light sources, a detector, a processor and a controller are configured such that light from the one or more light sources improves the ability of a human or automated motor vehicle driver to identify and avoid pedestrians. The one or more light sources may provide spot illumination to moving objects or pedestrians on a road surface, with the spot illumination following the moving object or pedestrians along the portion of the road surface. The one or more light sources may project images on the ground or on other surfaces. The light source may be carried by a pedestrian or on personal transport used by a pedestrian. The light sources may be stationary and provide lighting for a pedestrian street crossing.
1. A road lighting system deployed on or near a roadway, the road lighting system comprising:
one or more light sources;
one or more detectors arranged to detect a pedestrian on or near the roadway;
a processor configured to receive and process signals from the one or more detectors; and
a controller configured to receive signals from the processor and in response control the one or more light sources to illuminate a portion of the road surface and to provide spot illumination to the pedestrian that tracks the pedestrian as the pedestrian moves on or near the roadway;
the illumination of the pedestrian from the one or more light sources comprising a vertical illuminance component in a plane perpendicular to the roadway and a horizontal component in a plane parallel to the roadway, and the vertical illuminance component being at least twice the horizontal illuminance component.
2. The road lighting system of claim 1 , wherein the vertical illuminance component is at least five times the horizontal illuminance component.
3. The road lighting system of claim 1 , wherein:
the one or more detectors are arranged to detect a motor vehicle on the roadway approaching the pedestrian; and
the controller is configured to control illumination of the pedestrian so that the vertical illuminance component on the pedestrian is visible from the motor vehicle.
4. The road lighting system of claim 1 , wherein the spot illumination of the pedestrian comprises a spot of reduced horizontal illuminance in a plane parallel to the roadway that provides increased visual contrast and that surrounds and tracks the pedestrian.
5. The road lighting system of claim 1 , wherein:
the one or more light sources comprise an LED array; and
the controller is configured to receive signals from the processor and in response control pixels in the LED array to provide the spot illumination to the pedestrian that tracks the pedestrian as the pedestrian moves on or near the roadway.
6. The road lighting system of claim 1 , wherein
the one or more light sources comprise an LED array; and
the controller is configured to receive signals from the processor and in response control pixels in the LED array to provide illumination comprising a projection that tracks and at least partially surrounds the pedestrian as the pedestrian moves on or near the roadway.
7. The road lighting system of claim 6 , wherein the projection comprises an arrow that indicates a direction in which the pedestrian is moving.
8. The road lighting system of claim 6 , wherein the projection comprises a traffic sign, a text message, or a traffic sign and a text message visible to a vehicle driver approaching the pedestrian.
9. The road lighting system of claim 6 , wherein the horizontal illuminance of the projection in a plane parallel to the roadway is at least twice the horizontal illuminance of the surrounding roadway.
10. The road lighting system of claim 1 , wherein:
the one or more detectors are arranged to detect a motor vehicle on the roadway approaching the pedestrian;
the controller is configured to control illumination of the pedestrian so that the vertical illuminance component on the pedestrian is visible from the motor vehicle; and
the spot illumination of the pedestrian comprises a spot of reduced horizontal illuminance in a plane parallel to the roadway that provides increased visual contrast and that surrounds and tracks the pedestrian.
11. The road lighting system of claim 1 , wherein:
the one or more detectors are arranged to detect a motor vehicle on the roadway approaching the pedestrian;
the controller is configured to control illumination of the pedestrian so that the vertical illuminance component on the pedestrian is visible from the motor vehicle;
the one or more light sources comprise an LED array; and
the controller is configured to receive signals from the processor and in response control pixels in the LED array in the light source to provide the spot illumination to the pedestrian that tracks the pedestrian as the pedestrian moves on or near the roadway.
12. The road lighting system of claim 1 , wherein:
the one or more detectors are arranged to detect a motor vehicle on the roadway approaching the pedestrian;
the controller is configured to control illumination of the pedestrian so that the vertical illuminance component on the pedestrian is visible from the motor vehicle;
the one or more light sources comprise an LED array; and
the controller is configured to receive signals from the processor and in response control pixels in the LED array to provide illumination comprising a projection that tracks and at least partially surrounds the pedestrian as the pedestrian moves on or near the roadway.
13. The road lighting system of claim 12 , wherein the horizontal illuminance of the projection in a plane parallel to the roadway is at least twice the horizontal illuminance of the surrounding roadway.
14. A road lighting system deployed on or near a crosswalk in a roadway, the road lighting system comprising:
one or more light sources located above the crosswalk;
one or more light sources located at an end of the crosswalk;
one or more detectors arranged to detect a pedestrian on or near the roadway;
a processor configured to receive and process signals from the one or more detectors;
a controller configured to receive signals from the processor and in response control the one or more light sources locate above the crosswalk and control the one or more light sources located at an end of the crosswalk to illuminate a portion of the crosswalk and to provide spot illumination to the pedestrian that tracks the pedestrian as the pedestrian moves on or near the roadway;
the illumination of the pedestrian from the one or more light sources located above the crosswalk comprising a vertical illuminance component in a plane perpendicular to the roadway and a horizontal component in a plane parallel to the roadway, and the vertical illuminance component being less than the horizontal illuminance component; and
the illumination of the pedestrian from the one or more light sources located at an end of the crosswalk comprising a vertical illuminance component in a plane perpendicular to the roadway and a horizontal component in a plane parallel to the roadway, and the vertical illuminance component being greater than the horizontal illuminance component.
15. The road lighting system of claim 14 , wherein the illumination of the pedestrian from the one or more light sources comprises a vertical illuminance component in a plane perpendicular to the roadway and a horizontal component in a plane parallel to the roadway, and the vertical illuminance component is at least twice the horizontal illuminance component.
16. The road lighting system of claim 14 , wherein:
the one or more detectors are arranged to detect a motor vehicle on the roadway approaching the pedestrian; and
the controller is configured to control illumination of the pedestrian so that the vertical illuminance component on the pedestrian is visible from the motor vehicle.
17. The road lighting system of claim 14 , wherein the spot illumination of the pedestrian comprises a spot of reduced horizontal illuminance in a plane parallel to the roadway that provides increased visual contrast and that surrounds and tracks the pedestrian.
18. The road lighting system of claim 14 , wherein:
the one or more light sources comprise an LED array; and
the controller is configured to receive signals from the processor and in response control pixels in the LED array to provide the spot illumination to the pedestrian that tracks the pedestrian as the pedestrian moves on or near the roadway.
19. The road lighting system of claim 14 , wherein
the one or more light sources comprise an LED array; and
the controller is configured to receive signals from the processor and in response control pixels in the LED array to provide illumination comprising a projection that tracks and at least partially surrounds the pedestrian as the pedestrian moves on or near the roadway.
20. The road lighting system of claim 19 , wherein the projection comprises an arrow that indicates a direction in which the pedestrian is moving.
21. The road lighting system of claim 19 , wherein the projection comprises a traffic sign, a text message, or a traffic sign and a text message visible to a vehicle driver approaching the pedestrian.
22. The road lighting system of claim 19 , wherein the horizontal illuminance of the projection in a plane parallel to the roadway is at least twice the horizontal illuminance of the surrounding roadway.