Traditionally, the most common light source for headlamps has been the halogen filament lamp. Its key advantage is its low cost, and it is considered to represent a technically robust solution. The fact that it is replaceable makes up for the disadvantage of a limited service life. It does, however, have relatively high energy consumption and low efficiency at an average of 26 lumens per watt (L/W); and because of the light being radiated in all directions, halogen filament lamps offer poorer illumination performance overall compared to the alternatives.
LEDs Spearhead Drive Toward Intelligent Headlamps
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