Solar cells convert light to electricity. Image sensors also convert light to electricity. If you could do them both at the same time in the same chip, you’d have the makings of a self-powered camera. Engineers at University of Michigan have recently come up with just that, an image sensor that does both things well enough to capture 15 images per second powered only by the daylight falling on it.
With such an energy harvesting imager integrated with and powering a tiny processor and wireless transceiver you could “put a small camera, almost invisible, anywhere,” says Euisik Yoon, the professor of electrical engineering and computer science at University of Michigan who led its development. They reported their results this week in IEEE Electron Device Letters.