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Title: Frequency dependence of the acoustic field generated from a spherical cavity transducer with open ends

Abstract

Resolution of high intensity focused ultrasound (HIFU) focusing is limited by the wave diffraction. We have developed a spherical cavity transducer with two open ends to improve the focusing precision without sacrificing the acoustic intensity (App Phys Lett 2013; 102: 204102). This work aims to theoretically and experimentally investigate the frequency dependence of the acoustic field generated from the spherical cavity transducer with two open ends. The device emits high intensity ultrasound at the frequency ranging from 420 to 470 kHz, and the acoustic field is measured by a fiber optic probe hydrophone. The measured results shows that the spherical cavity transducer provides high acoustic intensity for HIFU treatment only in its resonant modes, and a series of resonant frequencies can be choosen. Furthermore, a finite element model is developed to discuss the frequency dependence of the acoustic field. The numerical simulations coincide well with the measured results.

Authors:
; ; ;  [1]; ;  [2]; ;  [3];  [4]
  1. State Key Laboratory of Ultrasound Engineering in Medicine Co-founded by Chongqing and the Ministry of Science and Technology, College of Biomedical Engineering, Chongqing Medical University, Chongqing 401121 (China)
  2. National Engineering Research Center of Ultrasound Medicine, Chongqing 401121 (China)
  3. Institute of Acoustics, Key Laboratory of Modern Acoustics, MOE, Nanjing University, Nanjing 210093 (China)
  4. Department of Physics, University of Vermont, Burlington, VT 05405 (United States)
Publication Date:
OSTI Identifier:
22492244
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Advances; Journal Volume: 5; Journal Issue: 12; Other Information: (c) 2015 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ACCURACY; COMPUTERIZED SIMULATION; DIFFRACTION; EMISSION; FIBERS; FINITE ELEMENT METHOD; FOCUSING; FREQUENCY DEPENDENCE; KHZ RANGE; RESOLUTION; SPHERICAL CONFIGURATION; TRANSDUCERS

Citation Formats

Li, Faqi, Zeng, Deping, He, Min, Wang, Zhibiao, E-mail: dzhang@nju.edu.cn, E-mail: wangzhibiao@haifu.com.cn, Song, Dan, Lei, Guangrong, Lin, Zhou, Zhang, Dong, E-mail: dzhang@nju.edu.cn, E-mail: wangzhibiao@haifu.com.cn, and Wu, Junru. Frequency dependence of the acoustic field generated from a spherical cavity transducer with open ends. United States: N. p., 2015. Web. doi:10.1063/1.4938523.
Li, Faqi, Zeng, Deping, He, Min, Wang, Zhibiao, E-mail: dzhang@nju.edu.cn, E-mail: wangzhibiao@haifu.com.cn, Song, Dan, Lei, Guangrong, Lin, Zhou, Zhang, Dong, E-mail: dzhang@nju.edu.cn, E-mail: wangzhibiao@haifu.com.cn, & Wu, Junru. Frequency dependence of the acoustic field generated from a spherical cavity transducer with open ends. United States. doi:10.1063/1.4938523.
Li, Faqi, Zeng, Deping, He, Min, Wang, Zhibiao, E-mail: dzhang@nju.edu.cn, E-mail: wangzhibiao@haifu.com.cn, Song, Dan, Lei, Guangrong, Lin, Zhou, Zhang, Dong, E-mail: dzhang@nju.edu.cn, E-mail: wangzhibiao@haifu.com.cn, and Wu, Junru. Tue . "Frequency dependence of the acoustic field generated from a spherical cavity transducer with open ends". United States. doi:10.1063/1.4938523.
@article{osti_22492244,
title = {Frequency dependence of the acoustic field generated from a spherical cavity transducer with open ends},
author = {Li, Faqi and Zeng, Deping and He, Min and Wang, Zhibiao, E-mail: dzhang@nju.edu.cn, E-mail: wangzhibiao@haifu.com.cn and Song, Dan and Lei, Guangrong and Lin, Zhou and Zhang, Dong, E-mail: dzhang@nju.edu.cn, E-mail: wangzhibiao@haifu.com.cn and Wu, Junru},
abstractNote = {Resolution of high intensity focused ultrasound (HIFU) focusing is limited by the wave diffraction. We have developed a spherical cavity transducer with two open ends to improve the focusing precision without sacrificing the acoustic intensity (App Phys Lett 2013; 102: 204102). This work aims to theoretically and experimentally investigate the frequency dependence of the acoustic field generated from the spherical cavity transducer with two open ends. The device emits high intensity ultrasound at the frequency ranging from 420 to 470 kHz, and the acoustic field is measured by a fiber optic probe hydrophone. The measured results shows that the spherical cavity transducer provides high acoustic intensity for HIFU treatment only in its resonant modes, and a series of resonant frequencies can be choosen. Furthermore, a finite element model is developed to discuss the frequency dependence of the acoustic field. The numerical simulations coincide well with the measured results.},
doi = {10.1063/1.4938523},
journal = {AIP Advances},
number = 12,
volume = 5,
place = {United States},
year = {Tue Dec 15 00:00:00 EST 2015},
month = {Tue Dec 15 00:00:00 EST 2015}
}
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