Fast Time-Domain Super-Resolution for Single-Shot Multi-Path ToF Imaging

This paper presents a fast and simple multi-path depth retrieval method based on the Inverse Discrete Fourier Transform (IDFT) for Indirect Time of Flight (IToF) imaging capable of achieving super-resolution in the time domain from a limited number of samples in the frequency domain. To this aim, an ad hoc hardware architecture providing quasi-optimal Fourier measurements by means of a single-shot multifrequency ToF sensor concept is exploited. The proposed method has been validated for one and two bounces, showing that the system is able to recover the distance to both targets in one shot with 16 frequencies (2 -32 MHz).

keywords: CMOS image sensor, macropixel, multi-frequency, multi-path, single-shot, ToF