Scientists have made the fastest camera ever. It can take 6.1 million pictures in a single second, at a shutter speed of 440 trillionths of a second. Light itself moves just a fraction of a centimeter in that time. The camera works by illuminating objects with a laser that emits a different infrared frequency for every single pixel, allowing them to custom-amplify a signal that would otherwise be too dim to see.“We have invented a new type of imaging technology that overcomes the fundamental limitation between sensitivity and speed,” said Keisuke Goda, an optoelectronic specialist at the University of California, Los Angeles. “It’s the world’s fastest camera.” High shutter speeds enable moving objects to be clearly photographed. The less time a camera’s optical eye is open, the less time a subject has to move. But this comes at a price: less light enters the camera, causing the image to be underexposed. That’s why sports photographers use high-powered strobe lights. Workarounds include the use of extra-sensitive chemicals in traditional films, or amplification of signals captured by the photoelectronic light sensors of digital cameras. But film is relatively limited in its range, as are digital cameras. At the speed of Godas camera, there isn’t enough light to magnify.
“The camera has a built-in optical image amplifier that overcomes the trade-off between sensitivity and speed,” he said. “It could be especially useful for microscopy. On the meta-microscale, even slow-moving objects require a high temporary resolution, because your field of view is so small.” The technology is dubbed STEAM, short for serial time-encoded amplified microscopy. It illuminates objects with an infrared laser that cycles through a series of different wavelengths, one for each pixel on the sensor. When reflected light hits the camera’s sensor, each pixel picks up its dedicated wavelength, and is given an electronic boost of a matching wavelength. That amplifies the original dim signal, composed of just a few photons, until it becomes visible. This can’t be done in a conventional digital camera, because the sensor doesn’t know what the original wavelengths were. For now, STEAM can only produce images composed of just 3,000 pixels, a far cry from the multi-million-pixel cameras used by consumers. But Goda’s team intends to develop a multi-megapixel camera that can take 100 million pictures per second, with a frame rate of they’re hoping to up this to mega-multipixel mode competitive with standard digital camers, taking 100 million pictures per second, with a shutter speed of just one-trillionth of a second. (Source:www.wired.co.uk)