DEVELOPMENT QF HOLOGRAPHIC CT SYSTEM FOR FIELD WORKS

开发用于野外作业的 QF 全息 CT 系统

• 批准号: 11555107
• 负责人: TAMURA Yasutaka
• 金额: $ 3.9万
• 依托单位: YAMAGATA UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1999
• 资助国家: 日本
• 起止时间: 1999 至 2001
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-11555107/
• 关键词: Ultrasound GT; Investigartion of historic relics; Echo waves; Piezoelectric polymer films

In the research, we propose an ultrasonic computed-tomography (CT) system for field works. The main purpose of the system is visualization of the internal structure of historic relics such as the wooden pillars of shrines. Using ultrasonic, we realized a safe and portable measuring system. However, there occur some problems in the application of ultrasonic to CT. The ultrasonic wavelength is considerably longer than X-ray wavelength, and, the propagation speed varies over a wide range. Hence, the ultrasonic wave properties significantly affect the CT images. Furthermore, the visualization process is also affected by outer shapes of objects and available acoustic paths.We have developed an ultrasonic TOP CT system which utilize data obtained by various sensors such as 3D position detector. A trial data acquisition for acoustical transducer array was constructed. The system consists of flexible modules connected each other with a serial buss. A 64ch digital pattern generator and array of switching amplifiers are available. The amplifiers are directly controlled by digital pattern signal. The output range is 2 Vpp to lOOVpp. The switching frequency range is 1KHz to 10MHz. Receivers are constructed with P(VDF-TrFE) copolymer films. A note-book type PC controlls the data acquisition system and a 3D position detector. The system is based on TOF-CT (Time-Of- Flight CT) method with FBP (Filtered Back Projection) algorithm. As an alternative visualization mode, the system can utilize reflected ultrasound echoes using "Hologram-Matrix method". The results of simulation and experiments indicated the availability of the system.

在研究中，我们提出了一个超声波计算机断层扫描（CT）系统的现场工作。该系统的主要目的是可视化历史文物的内部结构，如神社的木柱。利用超声波实现了一种安全便携的测量系统。然而，超声在CT中的应用也存在一些问题。超声波波长比X射线波长长得多，并且传播速度在很宽的范围内变化。因此，超声波特性显著地影响CT图像。此外，可视化过程也受到影响的外部形状的对象和可用的声paths.We开发了一个超声波TOP CT系统，它利用各种传感器，如3D位置探测器获得的数据。搭建了声换能器阵列数据采集实验平台。该系统由多个灵活的模块组成，通过串行总线相互连接。一个64通道数字模式发生器和开关放大器阵列可用。放大器直接由数字模式信号控制。输出范围为2 Vpp至100 Vpp。开关频率范围为1 KHz ~ 10 MHz。接收器由P（VDF-TrFE）共聚物膜构成。笔记本型PC控制数据采集系统和3D位置检测器。该系统是基于飞行时间CT（TOF-CT）方法与FBP（滤波反投影）算法。作为另一种可视化模式，该系统可以利用反射超声回波使用“全息矩阵方法”。仿真和实验结果表明了该系统的有效性。

项目成果

Naoki Yatame: "Edge Connected 2-D Array Constituted By Non-Linear Acoustic Device"JJAP. 41(印刷中). (2002)

Naoki Yatame：“由非线性声学器件构成的边缘连接二维阵列”JJAP 41（印刷中）。

竹内宏樹: "2次元ΔΣ変調による音場制御空間ローパスフィルタによるアレイのデシメーション"計測自動制御学会講演会予稿集(CD-ROM). 39. 303C-2 (2000)

Hiroki Takeuchi：“使用二维 ΔΣ 调制的声场控制。使用空间低通滤波器的阵列抽取”仪器与控制工程师协会会议记录 (CD-ROM) 39. 303C-2 (2000)。

吉澤重則: "3次元超音波撮像用アレイの構成と位置誤差補正"超音波エレクトロニクスの基礎と応用に関するシンポジウム予稿集. 21. 385-386 (2000)

Shigenori Yoshizawa：“三维超声成像阵列的配置和位置误差校正”超声电子学基础与应用研讨会论文集 21. 385-386 (2000)。

Naoki Yatame, , H. Yanagida and Y. Tamura: "New Edge Connected 2-D Array Using Non-Linear Acoustic Devices"Proceedings of USE2001. 22. 301-302 (2001)

Naoki Yatame、H. Yanagida 和 Y. Tamura：“使用非线性声学器件的新型边缘连接二维阵列”USE2001 论文集。

Naoki Yatame: "Edge Connected 2-D Electrostrictive Transducer Array for Biomedical Ultrasound Imaging"Proc. Of JSBB2001. 1(印刷中). (2002)

Naoki Yatame：“用于生物医学超声成像的边缘连接二维电致伸缩换能器阵列”Proc. JSBB2001（印刷中）。