  Recently three-dimensional (3D) imaging achieves tremendous success in
consumer and industrial manufacturing. However, current 3D imaging methods
rarely observe dynamical events happening in a short time interval due to the
imaging speed limitation. Here we propose a time-encoded single-pixel 3D
(TESP-3D) imaging method based on active infrared imaging with high-speed
structured illumination, which can acquire the 3D information of dynamic events
at an ultra-high frame rate. This method uses single-pixel photodetectors
instead of conventional CCD or CMOS devices as the imaging sensors to overcome
the image capturing speed limitation. As a proof of concept, we perform
continuous real-time 3D scanning imaging at a record 500,000 fps and acquire 3D
information of objects moving at a speed of up to 25 m/s. We anticipate that
this technology will have important applications in industrial on-line
inspection and high throughput 3D screening.
