March 1999

Laser-Lit Cars

By Technology Review

Engineers at Ford Motor Co. say taillights lit by lasers could lead to safer, more energy-efficient and better-looking automobiles. In an experimental design, fiber optics carry red light from a diode laser to a series of mirrors, which send the beam cascading across a 5-millimeter-thick sheet of acrylic. Reflective and refractive ridges direct the light outwards. Because they consume one-seventh the power of incandescent bulbs, lasers could prove useful in electric vehicles, says Ford lighting engineer Michael Marinelli. The thin acrylic would also allow designers to mold lights around contours. And since lasers flick on nearly instantaneously, Marinelli calculates drivers could see a car braking 0.2 seconds earlier, cutting highway stopping distance by 5 meters. Laser headlights are on the drawing board -but await development of cheap, powerful blue diode lasers.