A camera powered by the light it uses to take pictures has been invented by American scientists.
Theoretically the self-powered device could take a picture every second, forever.
“We are in the middle of a digital imaging revolution,” said Prof Shree Nayar, director of the computer vision laboratory at Columbia University in New York who invented the device. “A camera that can function as an untethered device forever – without any external power supply – would be incredibly useful.”
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