Influence of Non-Kolmogorov Turbulence on the Rayleigh Range of Partially Coherent Annular Beams

Abstract

The expression for the Rayleigh range of partially coherent annular beams propagating through non-Kolmogorov turbulence is derived, and the influence of turbulence parameters (generalized exponent parameter α , inner scale l 0 , outer scale L 0) and the beam parameters on the Rayleigh range is studied. It is shown that Rayleigh range z R| turb in turbulence decreases with increasing intensity of turbulence, and is always smaller than Rayleigh range z R| free in free space; z R| turb decreases with increasing L 0 (just for 3.6 < α < 4) and increases with increasing l 0 ; z R| turb does not monotonically vary with the increase of α , namely, it decreases firstly and then increases due to increasing α. When α = 3.11 , z R| turb reaches its minima. Additionally, the influence of turbulence on the Rayleigh range increases with increasing coherence parameter β , beam width w 0 and decreasing obscure ratio ε , beam orders M(N) .