The light that we see with our human eyes as a band of rainbow color falls in the range of what's called visible light.

我们用肉眼看到的彩虹色的光属于可见光。

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Researchers have trapped a rainbow - slowing light to a near-stop - in an array of 25, 000 "invisibility cloaks", each smaller than a hair's breadth.

BBC: 'Cloaking' idea traps a rainbow

The website explains how a rainbow is made from light and water - with help from the sun.

BBC: rainbow

Therefore you get more consistent colors, no rainbow effect and also, a lot longer life then light bulb based models.

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