<div class="htmlview paragraph">Recent admendments to the Federal Motor Vehicle Safety Standard No. 108 open new markets for headlamps of sealed construction utilizing the higher efficiency halogen regenerative cycle light sources.</div> <div class="htmlview paragraph">The terminology related to halogen-cycle lamps and the chemical/thermal cycle phenomena are explained for the automotive lighting engineers and references will allow researchers to review previous work.</div> <div class="htmlview paragraph">The history and practical applications of halogen lamps is traced from 1912 to the present halogen sealed beam headlamps that are available on numerous 1979 model automobiles. The new halogen sealed beam headlamps may be the initial step toward evolutionary new headlamp designs, involving new materials and new manufacturing processes to meet the changing needs of the automotive industry and society.</div>