A Market-Weighted Description of Tungsten-Halogen and LED Low-Beam Headlighting Patterns in the U.S.

Abstract

This report provides photometric information for low-beam headlamps on current U.S. light vehicles. Tungsten-halogen (TH) and LED lamps are included. The summaries presented here were based on photometric data provided by three vehicle manufacturers. The sample included data for 62 TH headlamps (in 31 left-right pairs) and 48 LED headlamps (in 24 left-right pairs). Collectively, the lamps are used on 45 vehicle models, which accounted for 36% of U.S. light-vehicle sales in 2018. The photometric information for each lamp was weighted by the sales figure for the corresponding vehicle. The results are presented in tabular form for the 25th-percentile, 50th-percentile (median), and 75th-percentile luminous intensities (from 25° left to 25° right, and from 5° down to 7° up). The results are also presented in graphical form as isocandela diagrams (from 25° left to 25° right, and from 5° down to 10° up).