Recent advances in vehicle forward lighting technology, coupled with the effects of new styling trends, have led to increased awareness and concerns regarding glare. New evidence suggests that the spectral content of vehicle forward lighting impacts the glare that it produces, specifically as measured by viewer discomfort. This paper explores how light source spectra affects discomfort glare and offers insight into the physiological mechanisms that may be responsible. A literature survey was undertaken to determine the current knowledge of how light spectrum affects glare in automotive forward lighting applications. Additionally, a field experiment is described that further explores the spectral aspects of discomfort glare. This experiment examined subject reaction to light sources of different spectral power distribution (SPD) and shows the relative contribution that short wavelength energy content makes to discomfort glare. The impacts of these results on new light sources for vehicle forward lighting, such as high intensity discharge (HID) systems and LED systems are discussed. There is good indication that the amount of relative energy in short wavelength region of the spectra is a determining factor in the amount of discomfort glare produced. Rod or scotopic stimulation does not seem to be the mechanism by which glare spectra affect discomfort. Preliminary results indicate that the spectral response consists of a combination of the SWC and photopic responses. This correlates with the studies described that show an effect of illuminance level (photopic stimulation) and SWC illuminance. The results of these investigations may have significant effects on the design of vehicle forward lighting systems. Designers may be able to increase the scotopic content of a source to maximize peripheral visibility for nighttime driving conditions.
Effects of vehicle forward lighting spectrum on glare
Einfluss des Scheinwerferlichtspektrums auf die Blendung
2003
11 Seiten, 5 Bilder, 16 Quellen
Aufsatz (Konferenz)
Englisch
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