Producing Bessel beams based on incoherent superposition of laser fields

摘要

Bessel beams belong to a class of propagation invariant, structured beams, and are used in a variety of applications, including particle micro-manipulation, optical coherence tomography, optical metrology, and high resolution microscopy. In practical applications, Bessel beams are formed by the interaction of optical fields with finite lateral dimensions. In this paper, we discuss the formation and propagation characteristics of Bessel beams based on input field distributions defined by Laguerre-Gaussian beams of different orders. We present the influence of the beam order on the shape and the axial intensity distribution of the resulting Bessel beams. One of the limiting factors in the applications of Bessel beams is related to the variations in the axial intensity distribution of the produced beams. We show that the incoherent superposition of input Laguerre-Gaussian beams of different orders can resolve the above limitation and produce Bessel beams with uniform peak intensity distributions over an extended axial distance.