Image formation of radially and temporally truncated Bessel beams

Abstract

The Fourier-lens-formatted image of a radially truncated Bessel beam is theoretically calculated and compared with the experimentally measured results. A peculiarity -the weak central spot in the focused image of an apertured Bessel beam -has been recorded for the first time. Femtosecond-domain temporal evolution of the image of two types of superluminal localized wave packets -the so-called Bessel-X pulse and the focused X wave -is studied theoretically. For the Bessel-X pulse the aperture truncation leads to appearance of twin pulses in the image plane. In the case of the focused X wave, the ring changes its colour revealing the full bandwidth of the ultrashort wave packet.