Ellis, said his group decided to recommend to patients the removal of all leads with frayed wires visible on X-rays, even if they work.

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X-rays, ultraviolet light and visible light particularly once it has weakened enough to stop emitting gamma rays.

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Its logo, an eye surrounded by dancing rays, is visible on T-shirts, bags, backpacks and scores of products targeted for young people up and down Jalan Malioboro, Jogjakarta's main business street.

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It's said the process is similar to how a CT scan functions, but uses visible light instead of X-rays.

ENGADGET

Unlike visible light, which cannot penetrate thick smoke and flames, the IR rays pass through largely unhindered.

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These tools span much of the electromagnetic spectrum from X-rays to ultraviolet to the infrared - and of course microscopy with visible light.

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