A new technique for generating non-diffracting beam with long propagation distance using two axicons

Abstract

A new technique for generating quasi non-diffracting beam with long propagation distance by using simple optical elements including the convergent lens and axicons is proposed. The theory of generating such a beam is studied with geometrical optics and diffraction theory. The formation process of the beam is simulated, and the transverse intensity distributions at various distances are obtained. The simulation results show that the transverse intensity distribution at long-distance accords with Bessel distribution. A comparison between the quasi non-diffracting beam, which is obtained by our experiment, and that in the literature (Belyi et al. 2010 Opt. Exp. 18 1966) shows that its propagation distance is more than 50 m longer, and the beam divergence angle is compressed by 22 times. In the experiment, the beam patterns are captured at different propagation positions, and the obtained results are in good agreement with the theoretical analyses.