RF トランスフォーマーでベッセルビームを生成する
まとめ
研究者は,単一の無線周波数 (RF) パワーアンプを使用してブロードバンドベッセルビームを作成する新しい方法を開発し,高度な超音波画像アプリケーションのサイズと電力を削減しました.
科学分野:
- 音学 と 波 現象
- 医療用画像技術
- 材料科学
背景:
- ベッセルビームは, difraktion-free 伝播と広い深さのフィールドを提供し,様々なアプリケーションに理想的です.
- 伝統的な超音波ベッセルビーム生成には,大量の電力集約型マルチアンプシステムが必要であり,ウェアラブルアプリケーションを制限しています.
研究 の 目的:
- 超音波アプリケーションのためのブロードバンドベッセルビームを生成するためのコンパクトで効率的な方法を開発する.
- 医療用ウェアラブル画像と超高解像度画像に ベッセルビームの応用を可能にします
主な方法:
- 単一の高圧無線周波数 (RF) パワーアンプとカスタム RF トランスフォーマーを使用した.
- PZTセラミック/ポリマー複合体製のカスタム製の10リング,2.5MHzのブロードバンド環状配列トランスデューサを使用した.
- 約 +/- 90 V の水中のパルスベッセルビーム.
主要な成果:
- 複数の増幅器,シミュレーション,理論と比べられるパルスベッセルビームを達成した.
- 約2.53mm (4.22波長) の -6dBのビーム幅を証明した.
- 約216mm (360波長) の有意な波深が得られた.
結論:
- この新しい方法は,ベッセルビーム生成システムのサイズ,重量,電力消費量を大幅に削減します.
- この進歩は,ベッセルビームをウェアラブル超音波装置に統合することを容易にする.
- スキャンされたリフレクターでベッセルビームを使用した3Dとマルチプレーンのイメージングの潜在能力を実証した.
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