MegaX, the first camera to capture the smallest particles of light

© 2020 EPFL - EPFL scientists, working in association with Canon, have developed a camera that can take 3D images with record-breaking speed and resolution - "It's something I'd been dreaming of for a long time," says Edoardo Charbon, an EPFL professor and head of the Advanced Quantum Architecture Laboratory in EPFL's School of Engineering. "MegaX is the culmination of over 15 years of research on single photon avalanche diodes (SPADs), which are photodetectors used in next-generation image-sensor technology." And Charbon has good reason to be proud, since he and his research team have developed the world's first million-pixel camera. Their findings have just been published in Optica . A shooting star What makes their camera different is that it can capture and count the very smallest form of light particle: the photon. Photons are invisible to the human eye; we can see only continuous beams of photons, like those used in laser pointers. But MegaX can film the trajectories of individual photons in rays of light. When shown in video form, they look like shooting stars. "We had to slow the film speed by a factor of 300 million to see individual photons move," says Charbon. But there's more to it. MegaX is extremely fast and can take up to 24,000 images per second; in comparison, movies are filmed at 24 images per second. MegaX also has three other important advantages: it has a very large dynamic range, can produce 3D representations and can perform in-depth segmentations of those representations - all at the same time. "Thanks to its high resolution and advanced detection capabilities," says Charbon, "MegaX could be used in applications that incorporate virtual and augmented reality." Reconstructing 3D images So how exactly does the camera work?