The technology available to image light as it moves through space continues to advance. Recently, we saw a new high-speed camera capture a small pulse reflected from a mirror; now, it's possible to image the entire flight path of a laser as it bounces around a laboratory.
This footage shows a new experimental set-up developed by researchers at Heriot-Watt University in Edinburgh, UK. It uses a 32 by 32 grid of detectors, used to record when photons arrive at a precise location. A little number crunching allows the sensor data to be turned into the video footage you see here—equivalent to recording the laser pulse's flight path at 20 billion frames per second.
While it's a neat academic achievement, there are some plausible applications for the detection system, too; the researchers reckon it could be used to measure the behavior of plasmas, for instance. But for now, let's just watch that pulse bounce back and forth. Isn't it great? [New Scientist]