Evolvable Acoustic Field Generated by a Transducer with 3D-Printed Fresnel Lens.

Danfeng Wang,Qiang Chen,Zhihai Qiu,Yan Wu,Chunlong Fei,Zeyu Chen,Lei Sun,Pengfei Lin,Xinhao Sun

doi:10.3390/mi12111315

Abstract

Evolvable acoustic fields are considered an effective method for solving technical problems related to fields such as biological imaging, particle manipulation, drug therapy and intervention. However, because of technical difficulties and the limited technology available for realizing flexible adjustments of sound fields, few studies have reported on this aspect in recent years. Herein, we propose a novel solution, using a Fresnel lens-focused ultrasonic transducer for generating excited-signal-dependent acoustic pressure patterns. Finite element analysis (FEA) is used to predict the performance of a transducer with a Fresnel lens. The Fresnel lens is printed using 3D additive manufacturing. Normalized intensity maps of the acoustic pressure fields are characterized from the Fresnel lens-focused transducer under various numbers of excited-signal cycles. The results demonstrate that under different cycle excitations, a temporal evolution acoustic intensity can be generated and regulated by an ultrasound transducer with a 3D Fresnel lens. This acoustical pattern control method is not only simple to realize but also has considerable application prospects.

Highlights

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We report on the use of a Fresnel lens in a single-element focused ultrasonic transducer for generating sound pressure modes corresponding to specific excitation signals
We started by employing a 5 MHz ultrasonic transducer with a diameter of 25 mm and a lens with f# = 0.6 (f# is the ratio of the radius of curvature of the lens to the diameter of the ultrasonic transducer) as the starting point to design the novel lens

Summary

Introduction

Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations. Many studies have discussed the method of diffraction-limited focusing by ultrasonic beam control technology using a multi-element array for phase modulation and correction [10,11,12]. This method can achieve effective sound field regulation, it is expensive and requires complex electronic equipment. New methods for sound field regulation must be developed

Methods

Results

Conclusion