Abstract
We present a rigorous approach to the propagation of a fully vectorial nonparaxial ultrashort pulsed beam in free space. By using the Fourier transform and the vectorial angular-spectrum formalism, we derive an exact fully vectorial integral solution of Maxwell's equations for an ultrashort pulsed beam whose pulse duration is as short as a single optical oscillation period. From this general expression we develop a Taylor expansion of electric field, and obtain all-order corrections to the paraxial pulsed beam solution, which is assumed to be known. Furthermore, the influence of vectorial nature on nonparaxial pulsed beam propagation is analysed and the vectorial nonparaxial correction is given in this paper.