高声阻层下指纹的高频超声成像实验  

High frequency ultrasonic imaging experiment for fingerprint under media with high acoustic impedance

作　　者：吴迪[1] 韦小鹤 毕超 张博南 王亚平[1] 滕永平[1] WU Di;WEI Xiao-he;BI Chao;ZHANG Bo-nan;WANG Ya-ping;TENG Yong-ping(Department of Physics, School of Sciences, Beijing Jiaotong University, Beijing 100044, China;Metals & Chemistry Research Institute, China Academy of Railway Sciences Co., Ltd, Beijing 100081, China;Beijing Xintai Zhihe Technology Development Co., Ltd, Beijing 100098, China)

机构地区：[1]北京交通大学理学院物理系,北京100044 [2]中国铁道科学研究院集团有限公司金属及化学研究所,北京100081 [3]北京信泰智合科技发展公司,北京100098

出　　处：《物理实验》2021年第7期17-22,共6页Physics Experimentation

基　　金：中央高校基本科研业务费专项资金资助(No.2019JBM067)。

摘　　要：分析了高频超声波垂直透过5层不同厚度介质的传播特性,利用传递矩阵推导出超声波在此多层结构的零界面处反射系数与各层介质厚度关系的解析表达式,用解析解做数值模拟,并用COMSOL有限元仿真验证,得到了超声回波在时域上的声学特征.使用高频超声换能器激发与采集分层介质中的超声宽频信号,得到玻璃层和模拟指纹层间反射回波中带有指纹特征的信息,形成了高精度超声指纹图像.The propagation characteristics of high frequency ultrasonic wave transmitted vertically through five layers of different medium thickness were analyzed,and the analytical expression of the relationship between the reflection coefficient of ultrasonic waves at the zero interface of this multilayer structure and the thickness of each medium layer was derived by using the transfer matrix.The acoustic characteristics of ultrasonic echo in time domain were simulated by numerical simulation with analytical solution and finite element simulation with COMSOL.The acoustic characteristics of ultrasonic echo in time domain were obtained.The wide spectrum ultrasonic reflection signal of fingerprint layer was detected by using high frequency ultrasonic transducer in the multilayer media,and interface echo data of glass interface with fingerprint resin layer were obtained.The information with human body fingerprint feature under high impedance glass layer was extracted,which could produce an ultrasonic fingerprint image with high imaging accuracy.

关 键 词：高频超声 分层介质 超声扫描成像 精细扫描 

分 类 号：O426[理学—声学]