2018 Fiscal Year Final Research Report
Hemi-sperical ultrasonic trasducer producing high power at low voltage
Project/Area Number |
16H03188
|
Research Category |
Grant-in-Aid for Scientific Research (B)
|
Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
Medical systems
|
Research Institution | Tohoku University |
Principal Investigator |
|
Co-Investigator(Kenkyū-buntansha) |
高木 亮 国立研究開発法人産業技術総合研究所, 生命工学領域, 研究員 (20771885)
吉澤 晋 東北大学, 工学研究科, 准教授 (30455802)
|
Research Collaborator |
ITO HIROSHI
|
Project Period (FY) |
2016-04-01 – 2019-03-31
|
Keywords | 音響キャビテーション / 圧電トランスデューサ / 超音波治療 / 結石破砕 |
Outline of Final Research Achievements |
A short ultrasonic pulse at an extremely high pressure is effective to generate acoustic cavitation, which remarkably enhances the efficiency of ultrasonic therapy and lithotripsy. However, if it is for a conventional thickness mode piezoelectric transducer, the required driving voltage may almost exceed the limit of MOSFETs. To overcome this problem, we have suggested a spherical transducer utilizing the co-resonance between a piezoelectric spherical shell and a water sphere. We are further suggesting a cylindrical transducer utilizing the co-resonance between a piezoelectric cylindrical shell and a water cylinder. Its principle was confirmed by a numerical simulation, and a prototype transducer was constructed, which proved that the ratio of acoustic output / driving voltage was in a realistic range.
|
Free Research Field |
医用超音波
|
Academic Significance and Societal Importance of the Research Achievements |
同半径の薄い圧電球殻と水玉の共振や,薄い圧電円筒と水円柱の共振を,電気的インピーダンスの低い圧電変換器を実現するのに利用することは,考え方として新規である.本研究の成果により実現される圧電変換器は,音圧出力/駆動電圧の比が優れているため,汎用半導体により構成されたアンプを用いて駆動することにより,超音波治療や結石破砕の効率と適用症例範囲を飛躍的に高める音響キャビテーションを生成できるようになる.これは,有用性の大きな医療機器の実用化に寄与するところ大である.
|