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Federal Highway Administration Research and Technology
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Publication Number: FHWA-HRT-04-145
Date: December 2005
Enhanced Night Visibility Series, Volume XIV: Phase III—Study 2: Comparison of Near Infrared, Far Infrared, and Halogen Headlamps on Object Detection in Nighttime Rain
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APPENDIX G—VES CHARACTERISTICS
This system uses a complex multireflector lens to focus the beam pattern created by the HID light source. The intensity of this beam is relatively low compared to other recent headlamp designs. This means that when compared to other headlamps using isocandela diagrams, this HID design puts out lower levels of light at specific points on the road. In addition to a bright light source, the beam pattern on this particular headlamp is quite narrow, meaning that much of the available light is directed more toward the center of the roadway and not as much to the periphery or the side of the roadway.
This system also makes use of a complex multireflector lens to focus the beam pattern created by the HID light source. The intensity of this beam is relatively high when compared to other recent headlamp designs. The beam pattern on this particular headlamp is considered to be fairly wide. A wide beam pattern not only directs light in the center of the roadway, but it also directs a considerable amount of light to the periphery or the side of the roadway.
As with all the other VESs, this system focuses its light output with a multireflector lens. The intensity of this headlamp compared to the others is in the middle range. The beam width is also average compared to the other designs.
This system again makes use of a complex multireflector lens to focus the beam pattern created by the HID light source. The intensity of this beam is relatively high when compared to other headlamps according to the different isocandela diagrams. The pattern of the beam of this headlamp is wider than most of the others.
This conventional headlamp has lower intensity characteristics relative to average halogen beams. The width of this beam is fairly narrow, similar to other halogens.
Topics: research, safety
Keywords: research, safety, deBoer, Detection, Disability Glare, Discomfort Glare, Halogen, High Intensity Discharge, Illuminance, Pedestrian
TRT Terms: research, Safety and security, Safety, Transportation safety, Headlight glare--Evaluation, Automobile driving at night, Automobiles--Lighting--Evaluation, Night visibility, Headlamps