Computational light-in-flight imaging using synthetic waves

Synthetic Light-in-Flight (SLiF) imaging is a novel computational approach to temporally and spatially resolve light pulses as they traverse through a volumetric scene or a scattering medium. In contrast to many state-of-the- art techniques that require pulsed lasers and/or high-speed detectors, SLiF only utilizes standard CMOS cameras and tunable CW lasers. The scene is captured at multiple “synthetic wavelengths”, which are the beat wavelengths of two closely spaced optical wavelengths. The acquired “synthetic fields” are stored and computationally superpositioned to form a “synthetic pulse.” Computational manipulation of phase and amplitude of the captured synthetic fields allows for the shaping of the synthetic pulse in space and time after its acquisition, which facilitates the decoding of different aspects of the captured scene. This contribution presents multiple SLiF measurement examples with up to 0.57ps temporal resolution and discusses potential applications in medical imaging and industrial inspection.