For a technology that doesn't get much respect, lightpipes are undergoing remarkably rapid applications growth. Lightpipes carry light from sources -- incandescent or fluorescent lamps or light-emitting diodes -- to illumination tasks. Applications include backlighting of liquid crystal displays, automobile dashboard and outside lighting, household appliance displays, and even large signs. By using computer modeling and learning basic rules of nonimaging optics, designers can make their lightpipes cheaper and more efficient…