In order to investigate within what areas on road silhouette as framed by the light from a meeting car, can be of help to the driver, a series of experiments have been performed. The experiments employed two stationary "meeting cars" standing at given distances from each other. These distances (110-400m) being determined by pre-experiments. On the area between the cars, "iso-silhouette" curves were measured using a special method for a number of silhouette-relevant conditions Factors favouring silhouette effects were found to be: narrow road, short distance between the cars, high road surface reflectance, inner band, the driver's eyes being high above the road, particles in the atmosphere, large spread of the meeting headlights beam.
Abstract