The Study On The Propagating Properties Of Radial Beam Arrays

The laser array beams which consists of beams with different initial constant phase in a well-ordered distribution have been widely investigated both experimentally and theoretically due to their wide applications to high-power systems, inertial confinement fusion, high-energy weapons and so on. The beam array also could be used to form a vortex light.In this paper, we mainly study the propagating properties of the radial beam array.In the second part of our paper, basing on the coherent superposition principle and the generalized Huygens- Fresnel diffraction integral, the properties of a radial beam array with determined initial phase distributions propagating through a turbulent atmosphere are analytically investigated. It is shown that, when the propagation distance is short, the output intensity distribution will gradually becomes a spiral shape, which denotes a vortex. However, under the effect of the atmospheric turbulence, the output vortex property gradually disappears, and become to a center-bright beam without vortex property. Furthermore, the weaker the atmospheric turbulence is, the longer distance the output optical vortex (the center-dark beam) can propagate over.In the third part, using the principle of coherence, we study the properties of the beam array with radial or azimuthal polarized propagating in the free space. We find that the irradiance in the centre will disappear as propagating. And in the propagation, under the effect of coherence, as the distance increases, the radial or azimuthal polarization could keep its polarization basically. But the polarization at the edges of the beamlets will be destroyed.It is the keystone in the paper that we study the two models both could produce the optical vortex.