Innovations in Low Pressure Discharge Lighting

The automotive lighting industry has undergone major changes over the past 25 years. The sealed beam lamp, the industry standard for half a century has been replaced by a number of new aerodynamic headlamps. Over this same time period signal lighting has undergone dramatic changes; from a standard hand signaling for brake and turn, to complex multi-cavity systems for running, turn, and stop lighting. In the interior of the vehicle similar changes have also occurred which have dramatically improved driver visibility of the instrument cluster. In all three application areas major changes are continuing to occur particularly in the light source and optics of the illumination system. This paper discusses some of these changes and compares the various light sources and optical systems used to illuminate the space around the automobile and the communication between vehicles. While the forward illumination has been the dominant element in lighting, signaling to improve accident avoidance is becoming of equal importance. The central theme of this paper is to provide information about the various sources with a particular emphasis on the neon discharge light source and its auxiliary system components that can expand our communication ability.