A flat acoustic lens to generate a Bessel-like beam

Zheng Xu; Wei Xu; Menglu Qian; Qian Cheng; Xiaojun Liu

doi:10.1016/j.ultras.2017.05.005

A flat acoustic lens to generate a Bessel-like beam

Ultrasonics. 2017 Sep:80:66-71. doi: 10.1016/j.ultras.2017.05.005. Epub 2017 May 9.

Authors

Zheng Xu¹, Wei Xu², Menglu Qian¹, Qian Cheng³, Xiaojun Liu⁴

Affiliations

¹ Institute of Acoustics, Tongji University, Shanghai 200092, China.
² Department of Spine Surgery, Tongji Hospital, Tongji University School of Medicine, Shanghai 200065, China.
³ Institute of Acoustics, Tongji University, Shanghai 200092, China. Electronic address: q.cheng@tongji.edu.cn.
⁴ Key Laboratory of Modern Acoustics, Department of Physics, Nanjing University, Nanjing 210093, China. Electronic address: liuxiaojun@nju.edu.cn.

PMID: 28505607
DOI: 10.1016/j.ultras.2017.05.005

Abstract

We report a flat acoustic lens with a periodical structure to transform a divergent beam into a Bessel-like beam. Using the Schlieren imaging technique, the propagation process of acoustic wave in the periodical structure was experimentally observed. The pressure distribution in the main lobe is in good agreement with the Bessel function and the positions of the side lobes are close to the peak of the Bessel function. To observe the directivity of the beam, simulations were performed using the finite-element method. The simulation results indicated that the transmitted acoustic intensity at the central axis was several times greater with the lens than without it. The applicability of the lens for detecting the location of an acoustic source was also investigated.

Keywords: Acoustic lens; Bessel beam; Periodical structure; Schlieren imaging technique.

Publication types

Research Support, Non-U.S. Gov't