Investigation of Safety-Based Advanced Forward-Lighting Concepts to Reduce Glare

This two-part report addresses the feasibility of two approaches for using adaptive forward-lighting systems (AFS) to reduce headlamp glare under different conditions. AFS approaches involve dynamically changing headlamp beam patterns that respond in real time to different surrounding conditions such as roadway geometry, ambient lighting, or the presence of other drivers. In the first part, four field studies are described that investigated interactions between roadway lighting and vehicle headlamps, to determine whether dimming headlamps can be a suitable AFS strategy when roadway lighting is present. The studies found that glare impairs drivers’ forward visibility and produces feelings of discomfort, even when street lighting is present, and that in lighted areas, it is possible to dim headlamps (potentially via AFS), reducing glare to oncoming and preceding drivers, without significantly impairing drivers’ performance with respect to detection distance. In the second part, another AFS approach was investigated. This approach involved use of a "prime beam" optimized for forward visibility as the main beam pattern, subtracting portions of light when needed to reduce glare to oncoming or preceding drivers. A prototype system using a prime beam was developed, evaluated for visibility and glare in field tests in comparison with conventional low and high beam patterns, and demonstrated on a moving vehicle. The prime beam approach appears to be a promising one to ensure adequate forward visibility under a wide range of conditions while controlling glare to other drivers, and for studying characteristics of lighting as they pertain to visual performance and safety.

• Corporate Authors:

  Rensselaer Polytechnic Institute

  Lighting Research Center, 21 Union Street
  Troy, NY  United States  12180

  National Highway Traffic Safety Administration

  1200 New Jersey Avenue, SE
  Washington, DC  United States  20590
• Authors:
  • Bullough, John D
  • Skinner, Nicholas P
  • Akashi, Yukio
  • Van Derlofske, John
• Publication Date: 2008-9

Language

• English

Media Info

• Media Type: Print
• Edition: Final Report
• Features: Appendices; Figures; References; Tables;
• Pagination: 82p

Subject/Index Terms

• TRT Terms: Glare; Headlamps; High beamed headlamps; Low beamed headlamps; Street lighting; Visibility; Visibility distance
• Uncontrolled Terms: Advanced headlamps
• Subject Areas: Highways; Safety and Human Factors; Vehicles and Equipment; I91: Vehicle Design and Safety;

Filing Info

• Accession Number: 01126402
• Record Type: Publication
• Report/Paper Numbers: HS-811 033
• Files: HSL, TRIS, USDOT
• Created Date: Apr 13 2009 2:59PM