Generation of long-range nondiffracting narrow light beams

Abstract

A type of nondiffracting narrow light beam that propagates across a long range with a narrow beamwidth is presented. This beam is formed by a distorted concave spherical wave front that can be generated by a Galilean transmitting telescope with an eyepiece that has a spherical aberration. We observed an unusual image with a striped pattern in the laser beam's atmospheric backscatter that provided an opportunity to examine this effect. We demonstrate the mechanism of the generation and the characteristics of the long-range nondiffracting beam. The results show that a nondiffracting core beam with a width of the order of millimeters with a propagation distance of the order of a kilometer is generated by a 10-cm-diameter laser beam.

Bessel-like beams with z-dependent cone angles

“…Such schemes have been investigated before, mainly with the aim of obtaining the maximally uniform an-axis profile and constant diameter of the central spot size at the given focal segment as well as with the aim of minimization of astigmatism that is typically large for conical optics [17]. In the papers [18][19] the possibility is shown of achieving of a high transverse resolution at large distances in a scheme of a defocused Galileantype telescope with negative spherical aberration. However until now there has not been a detailed investigation of the transverse structure of z-dependent Bessel beams in the near and far zones of diffraction and the possibility of managing the axial intensity of a generated beam by the change of scheme parameters.…”

Numerical simulation of wavefronts diffracted by apertures with circular symmetry

“…The Gauss beam truncated by the apertures (the circular aperture or the annular aperture) has a lower degree of divergent. The divergence decreases when the beam is truncated seriously, just as the nondiffracting beam [8][9][10][11].…”

Development of high intensity laser-electron photon beams up to 2.9 GeV at the SPring-8 LEPS beamline

“…Simultaneously, the Rayleigh range or the effective range for the laser-electron collisions becomes shorter by reducing the beam waist size. Therefore, we plan the next tests to extend the Rayleigh range with a slight reduction of the peak power density by using a technique of a long range non-diffractive beam (LRNB) [18].…”