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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These can be made to emit white light by coating the device with a phosphor compound that absorbs part of the blue light and re-emits it as yellow.

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When a voltage is applied across the coating, the window darkens, allowing less light to enter but still permitting a view.

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With the addition of a reinforced, glass lens cover, the EX-G1 is tooled with a multi coating that is water-repellent and prevents light reflection from ruining pictures.

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Another is to add a coating on the glass covering the cells to reduce glare and allow more light to enter the cells.

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As the sun readies itself for the day's end, the light turns hazy and golden, coating every scene with the warm graininess of a Super 8 home movie.

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The polymers were covered with a thin aluminum coating, but once fed electricity, they began to glow so brightly that light shone through the metal.

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