As fancy as cameras get, they continue to have one big problem: When their batteries stop working, so do they. Now, engineers have developed a prototype camera that powers itself with the light it gathers. The device’s sensor contains circuitry that doesn’t just collect light to form an image; it converts light into power like a solar cell does. After the sensor collects enough light to charge up its energy-storing components (a process that takes just a few milliseconds), it uses that energy to record and read out an image, the researchers will report on 25 April in Houston, Texas, at the International Conference on Computational Photography. Then, it swings back into recharge mode. The researchers used the 30-by-40-pixel sensor to record videos (above) that capture one frame of video per second. Each pixel in the prototype device is about 4 millimeters across, about 1000 times the size of a pixel found on a typical digital camera’s light-collecting sensor. But if the new prototype’s circuitry were miniaturized and etched onto an energy-efficient chip, it could readily power itself in a moderately sized, lamp-lit room and capture 640-by-480-pixel video (a standard size known as Video Graphics Array, or VGA) at a rate of 30 frames per second, the researchers estimate.

Source: sciencemag.org