Philips' solution is to combine two blue and one red element, but use a green phosphor filter to convert one of the blue LEDs to green.

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The Phosphor Reveal line offers six style choices: pink, red, white and black patent leather for women with crystal-adorned face frame, and two black matte leather men's band choices with or without adorned top ring.

ENGADGET: Phosphor's Reveal wristwatch uses Swarovski crystals to tell time, bedazzle you

Generally LED bulbs use either a combination red, green and blue LEDs to create white light, or they use a phosphor coating (more common) in combination with a blue LED.

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