Online Journal
IF値: 1.878(2021年)→1.8(2022年)


Journal of Medical Ultrasonics

にて英文誌のFull textを閲覧することができます.


1994 - Vol.21

Vol.21 No.09

Original Article(原著)

(0573 - 0582)


Measurement of Ultrasonic Phase Distortion by Propagation Through a Inhomogeneous Layer Using a Hydrophone

杉本 和子1, 田部井 誠2, 上田 光宏3

Kazuko SUGIMOTO1, Makoto TABEI2, Mitsuhiro UEDA3

1東京工業大学物理情報工学専攻, 2東京工業大学精密工学研究所, 3東京工業大学理工学国際交流センター

1Department of Information Processing, Tokyo Institute of Technology, 2Precision and Intelligence Ladoratory, Tokyo Institute of Technology, 3International Cooperation Center for Science and Technology, Tokyo Institute of Technology

キーワード : Inhomogeneous layer, Hydrophone, Phase distortion, Ultrasonic holography

Phase of sound pressure is distorted and quality of ultrasonic images is degraded when ultrasonic waves propagate through a inhomogeneous layer. A few studies report experimental measurement of this phase distortion with a linear array transducer. In the present study, we propose an accurate method of measurement that uses a hydrophone. In experiment, soft tissue (porcine liver, meat, and tendon) was placed near the surface of a flat transducer, and distortion of ultrasonic wavefront after propagation through this tissue was reconstructed using an aperture synthesis technique based on sound pressure distribution measured at plane of observation. Influence of both a fluctuation of sound velocity during measurement and a inclination of plane of observation to the plane of transducer surface is compensated for in this data-processing scheme. In addition, this effect was demonstrated by phantom experiments for analyzing the accuracy of this method of measurement.