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There are two primary ways of producing white light-emitting diodes (WLEDs), LEDs that generate high-intensity white light. One is to use individual LEDs that emit three primary colors—red, green, and blue—and then mix all the colors to form white light. The other is to use a phosphor material to convert monochromatic light from a blue or UV LED to broad-spectrum white light, much in the same way a fluorescent light bulb works.
There are three main methods of mixing colors to produce white light from an LED:
 "GaN-based blue light emitting device development by Akasaki and Amano" (PDF). Takeda Award 2002 Achievement Facts Sheet. The Takeda Foundation. April 5, 2002. Retrieved November 28, 2007.