Shaping the on-axis intensity profile of generalized Bessel beams by iterative optimization methods


Runze Li and Xianghua Yu and Tong Peng and Yanlong Yang and Baoli Yao and Chunmin Zhang and Tong Ye

“The Bessel beam belongs to a typical class of non-diffractive optical fields that are characterized
by their invariant transverse profiles with the beam propagation. The extended and uniformed
intensity profile in the axial direction is of great interest in many applications. However, ideal
Bessel beams only rigorously exist in theory; the Bessel beams generated in the experiment are
always quasi-Bessel beams with finite focal extensions and varying intensity profiles along the
propagation axis. The ability to shape the on-axis intensity profile to meet specific needs is
essential for many applications. Here, we demonstrate an iterative optimization based approach
to engineer the on-axis intensity of Bessel beams through design and fine-tune processes.
Starting with a standard axicon phase mask, the design process uses the computed on-axis beam
profile as a feedback in the iterative optimization process, which searches for the optimal radial
phase distribution that can generate a so-called generalized Bessel beam with the desired on-axis
intensity profile. The fine-tune process repeats the optimization processing by using the adjusted
target on-axis profile according to the measured one. Our proposed method has been
demonstrated in engineering several quasi-Bessel beams with customized on-axis profiles. The
high accuracy and high energy throughput merit its use in many applications. This method is also
suitable to engineer higher-order Bessel beams by adding appropriate vortex phases into the
designed phase mask.”

Link to Publications Page

Publication: Journal of Optics

Issue/Year/DOI: Journal of Optics, Volume 20, Number 8 (2018)

DOI: 10.1088/2040-8986/aace46