Fluorescent Lights Get A Green Glow

FLUORESCENT LIGHTS ARE CHEAP, EFFICIENT, AND BRIGHT. But because they contain mercury, a highly toxic gas that damages the environment, they are far from perfect. Now, in this week's Science, researchers from Utrecht University in the Netherlands report an important advance in the quest for a "greener" fluorescent light.

Turning on a fluorescent lamp involves more than flipping a switch. It requires both particle physics and chemistry to do the job. When electricity passes through the mercury-filled tube, the liquid vaporizes and emits ultraviolet (UV) light particles called photons. Next, phosphors, crystals on the inner walls of the tube, absorb the UV light and re-emit the energy to make white light.