Red Light, Green Light

Researchers at Philips and the University of Amsterdam in the Netherlands have created the first material for light-emitting diodes (LEDs) and flat-panel displays that can glow two different colors. Other electroluminescent materials, like the familiar LED indicators on VCRs, emit light of one fixed hue when electricity flows through them. As a result, multicolor devices, such as flat-screen televisions and computer monitors, have required three different materials-one each for red, green, and blue.

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