"LED: Reflector lets LEDs replace light bulbs"
Light bulbs create more heat than light. But a professor at Rensselaer Polytechnic Institute (Troy, N.Y.) has invented a 99 percent efficient, omnidirectional reflector that he claims will allow light-emitting diodes to replace conventional light bulbs within five years, saving energy and related cost. Fred Schubert, Wellfleet senior constellation professor of the Future Chips Constellation at Rensselaer, has demonstrated his LEDs in red and blue but is pursuing white LEDs for light bulb replacement. "In an LED, light emits from inside the semiconductor in every direction, but our mirror reflects light equally well no matter what the angle of incidence. Other types of reflectors are only efficient when the angle is normal [90� perpendicular to the surface]," Schubert said.