Direct space-time characterization of the electric fields of ultrashort optical pulses

We report the complete spatiotemporal characterization of ultrashort light pulses by use of a self-referencing device based on shearing interferometry in the space and frequency domains. The apparatus combines a spatially resolved spectral shearing interferometer with a spectrally resolved spatial shearing interferometer. The electric field as a function of one transverse spatial coordinate and time is obtained from a single experimental trace by means of a direct and fast algebraic phase reconstruction algorithm. The method has been tested in several common laboratory situations. (C) 2002 Optical Society of America.