中国激光, 2018, 45 (10): 1007001, 网络出版: 2018-10-12   

基于激光诱导超声换能器的磁声电成像研究 下载: 713次

Magneto-Acousto-Electrical Tomography Based on Laser-Induced Ultrasound Transducers
作者单位
1 中国科学院电工研究所, 北京 100190
2 中国科学院大学, 北京 100049
摘要
生物组织的电学特征对肿瘤的早期诊断具有重要意义。通过测量样品的洛伦兹力效应, 磁声电成像可以检测到生物组织电导率的变化, 从而实现肿瘤组织的早期诊断。现有的磁声电成像采用传统的压电超声换能器产生超声激励, 为了避免静磁场对超声激励系统的干扰, 这种方法要求压电超声换能器必须远离被测样品, 从而导致超声探头和被测样品间存在较大的超声传播距离, 不利于在临床中进一步研究。首先设计了基于光声热弹效应的激光诱导超声换能器, 这种光学超声换能器采用优化的炭黑和聚二甲基硅氧烷复合结构, 减小了复合膜厚度, 有望产生高频和高强度超声信号; 然后对优化的复合膜激光诱导超声换能器的超声特性进行分析, 并利用激光诱导超声换能器进行磁声电成像实验。结果表明:激光诱导超声换能器产生的超声信号具有与压电换能器产生的超声信号可比的压强幅度和超声带宽, -6 dB超声带宽接近7.5 MHz, 产生的超声强度达到2.5 MPa; 在磁场环境中, 激光诱导超声换能器能提供一种无电子结构的超声激励方式, 有效减小了磁声电成像中超声激励源的电磁干扰, 具有良好的电磁兼容特性。
Abstract
Electrical characteristics of biological tissues are significant for early diagnosis of tumor tissues. Through detecting the Lorentz force effect of the samples, magneto-acousto-electrical tomography is confirmed to have ability to implement early diagnosis of tumor tissues with recognition of changes in electrical conductivity of organisms. In all previous work on magneto-acousto-electrical tomography, incident ultrasonic pulses are generated from conventional piezoelectric transducers. To avoid the electromagnetic interference to the ultrasonic excitation system, the piezoelectric transducer is required to be placed far away from the detected sample. However, the long distance of ultrasonic propagation between the ultrasonic transducer and the sample limits further clinical research. Firstly, laser-induced ultrasound transducers based on photoacoustic effect are proposed. The optic ultrasonic transducers are polymer-nanomaterial composites formed by carbon black and polydimethylsiloxane, which are promising to generate high-frequency and high-intensity ultrasonic signals through decreasing the thickness of composite films. The acoustic fields generated by optimized laser-induced ultrasound transducers are then characterized, and laser-induced ultrasound transducers are applied in the magneto-acousto-electrical tomography experiment. The results indicate that the output pressure and bandwidth of the ultrasonic signals generated by the laser-induced ultrasound transducers are similar to or better than those generated by the piezoelectric transducers. -6 dB frequency bandwidth and acoustic intensity of the laser-induced ultrasound transducers are measured to be about 7.5 MHz and 2.5 MPa, respectively. Due to the absence of electronics and metal in the laser-induced ultrasound transducers, acoustic sources generated by the laser-induced ultrasound transducers are compatible with magneto-acousto-electrical tomography and insensitive to electromagnetic interference.

丁广鑫, 夏慧, 刘国强, 李元圆, 王丽丽. 基于激光诱导超声换能器的磁声电成像研究[J]. 中国激光, 2018, 45(10): 1007001. Ding Guangxin, Xia Hui, Liu Guoqiang, Li Yuanyuan, Wang Lili. Magneto-Acousto-Electrical Tomography Based on Laser-Induced Ultrasound Transducers[J]. Chinese Journal of Lasers, 2018, 45(10): 1007001.

本文已被 1 篇论文引用
被引统计数据来源于中国光学期刊网
引用该论文: TXT   |   EndNote

相关论文

加载中...

关于本站 Cookie 的使用提示

中国光学期刊网使用基于 cookie 的技术来更好地为您提供各项服务,点击此处了解我们的隐私策略。 如您需继续使用本网站,请您授权我们使用本地 cookie 来保存部分信息。
全站搜索
您最值得信赖的光电行业旗舰网络服务平台!