Evaluation of the Feasibility of a Single-Beam Headlighting System

摘要

The study sought to develop an improved headlamp beam for use in conditions of oncoming or preceding traffic. A number of candidate beam patterns were offered for consideration from several sources. These were evaluated by two computer models. One of these models estimates the visibility distance provided to various areas and under a variety of road conditions. The other model produces a 'figure of merit' for each beam, which is the percent of time it simultaneously meets certain visibility and glare criteria. Based on this evaluation, three different beam patterns were selected for field testing. The three beams were fabricated and evaluated both objectively and subjectively. The objective tests were run on public roads, using targets which appeared normal to the environment. The subjects were not aware of the purpose of the test. The subjective evaluation was run on a wide variety of roads and solicited opinions concerning many aspects of beam performance. The results of both studies indicated that under some conditions the test beams provided marginal improvement over the SAE units used as controls.