That doesn't give the camera sensor much light to work with, but because the femtosecond bursts are so quick and because the camera sensor takes measurements every few picoseconds--or trillionths of a second--it can gather a lot of data quickly. By moving the laser slightly each time it fires a burst, the light also enters the space where the target object is at various angles, helping to define the geometry of the object being imaged. The returning light from all of these bursts enables the camera to put together a strikingly good image of the object hiding around the corner. That could help rescue workers or military operators see dangers around the next bend, or help the automated automobiles of the future see around blind corners. All is explained in the video below, and there's more detail (and another informative video) over at MIT News.