Characterization of the constituent wave of a diffracting and a nondiffracting axisymmetric laser beam

Guy Rousseau,Michel Piché,David Gay

doi:10.1364/opex.13.007589

Abstract

We show experimentally how diffracting and nondiffracting laser beams can be characterized through their one-dimensional constituent wave. Such a wave stems from an angular decomposition applicable to any cylindrically symmetric laser beam. In our experiment, spatial filtering in a 4-f system is used to generate the constituent wave of each beam under study. Standard one-dimensional root-mean-square (rms) parameters, such as the propagation factor and the generalized Rayleigh range, are then applied to determine the regime of propagation of the beams to characterize.

Highlights

Numerous analytical solutions describing laser beams with cylindrical symmetry can be found in the literature
In the beam propagation experiment, the intensity distribution of the resulting beam and that of its constituent wave were captured in the reference plane z = 0 and in six planes on either side of the reference plane
We have introduced an experimental technique allowing for the production of diffracting and Bessel-type nondiffracting laser beams from an Airy diffraction pattern

Summary

Introduction

Numerous analytical solutions describing laser beams with cylindrical symmetry can be found in the literature. Laguerre-Gauss beams [1] present, for a given waist radius, a far-field divergence that is a function of their azimuthal and radial orders. Bessel beams [2] are known to exhibit a nondiffracting behavior but would require an infinite amount of energy for their realization. Other solutions, such as Bessel-Gauss beams [3,4], can propagate in either a diffracting or a nondiffracting regime, depending on the relative value of their parameters. A scalar and paraxial analysis [5] has established more specific criteria to determine in a quantitative manner the regime of propagation of cylindrically symmetric laser beams. The approach relies on the fact that any laser beam of well-defined azimuthal order, hereafter called the resulting beam, can be constructed from a single wave, which has been

Methods

Results

Conclusion