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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The new bulbs will house a "rainbow" of over 100 bulbs that can deliver three types of light.

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And the sky is blue, it says, because the sun produces white light which is made up of all the colours of the rainbow.

BBC: rainbow