A trillion frames per second: the techniques and applications of light-in-flight photography

TL;DR

This paper reviews techniques for capturing light-in-flight at a trillion frames per second, enabling new imaging applications like 3D scene reconstruction behind obstacles and studying ultrafast optical phenomena.

Contribution

It provides a comprehensive overview of the main techniques for ultra-high speed photography focused on light-in-flight imaging and its diverse applications.

Findings

Demonstrates capabilities of trillion fps cameras to freeze light motion

Highlights applications in 3D imaging behind occlusions and ultrafast process analysis

Discusses computational methods enhancing ultra-high speed imaging

Abstract

Cameras capable of capturing videos at a trillion frames per second allow to freeze light in motion, a very counterintuitive capability when related to our everyday experience in which light appears to travel instantaneously. By combining this capability with computational imaging techniques, new imaging opportunities emerge such as three dimensional imaging of scenes that are hidden behind a corner, the study of relativistic distortion effects, imaging through diffusive media and imaging of ultrafast optical processes such as laser ablation, supercontinuum and plasma generation. We provide an overview of the main techniques that have been developed for ultra-high speed photography with a particular focus on `light-in-flight' imaging, i.e. applications where the key element is the imaging of light itself at frame rates that allow to freeze it's motion and therefore extract information that would otherwise be blurred out and lost.