Complete temporal pulse characterization based on phase reconstruction using optical ultrafast differentiation (PROUD).

A simple and general technique for recovering the phase profile of a given optical waveform from temporal intensity measurements is introduced and experimentally demonstrated. The proposed method involves the measurement of the temporal intensity profiles at the input and output of a linear optical time differentiator. The signal phase profile can be unambiguously recovered from these intensity measurements using a direct and noniterative algorithm. Given that ultrafast optical differentiators can be readily implemented in all-fiber or free-space platforms, the proposed technique could be applied over time waveforms with durations ranging from the subpicosecond to the nanosecond regime.