A transmission and reflection coupled ultrasonic process tomography based on cylindrical miniaturized transducers using PVDF films

作者：Gu, J.; Yang, H.; Fan, F.; Su, M.^*

来源：Journal of Instrumentation, 2017, 12(12): P12026.

DOI：10.1088/1748-0221/12/12/P12026

• Multi-modality systems
• Data processing methods
• Detector design and construction technologies and materials
• Particle identification methods

A transmission and reflection coupled ultrasonic process tomography has been developed, which is characterized by a proposed dual-mode (DM) reconstruction algorithm, as well as an adaptive search approach to determine an optimal image threshold during the image binarization. In respect of hardware, to improve the accuracy of time-of-flight (TOF) and extend the lowest detection limit of particle size, a cylindrical miniaturized transducer using polyvinylidene fluoride (PVDF) films is designed. Besides, the development of range-gating technique for the identification of transmission and reflection waves in scanning is discussed. A particle system with four iron particles is then investigated numerically and experimentally to evaluate these proposed methods. The sound pressure distribution in imaging area is predicted numerically, followed by the analysis of the relationship between the emitting surface width of transducer and particle size. After the processing of experimental data for effective waveform extraction and fusion, the comparison between reconstructed results from transmission-mode (TM), reflection-mode (RM), and dual-mode reconstructions is carried out and the latter manifests obvious improvements from the blurring reduction to the enhancement of particle boundary.

• 出版日期2017-12
• 单位上海理工大学