Electrical Tuning of Focal Size with Single Focused Ultrasonic Transducer
Electrical Tuning of Focal Size with Single Focused Ultrasonic Transducer
复制标题
使用单聚焦超声波换能器对焦距进行电调谐
DOI：
10.1109/ultsym.2018.8579883
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发表时间：
2018
期刊：
影响因子：
--
通讯作者：
E. S. Kim
中科院分区：
文献类型：
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作者：
Yongkui Tang;E. S. Kim
本文通过修改自聚焦声学换能器（SFAT）的设计，描述了一种具有电可调焦点尺寸的单元件平面聚焦超声换能器。该换能器构建在 1 毫米厚的锆钛酸铅 (PZT) 上，具有 (1) 顶部由环形气腔形成的菲涅耳声透镜和 (2) 底部形成图案的环形电极。通过控制从中心驱动的菲涅尔环的数量，我们能够使用 2.32 MHz 脉冲超声波将焦点尺寸调整在 371 至 866 µm 之间，同时将焦距保持在 6 mm。当作为液滴喷射器进行测试时，传感器喷射直径在 294 至 560 µm 之间（体积在 13.3 至 92.0 nL 之间）的水滴，具体取决于驱动哪组电极。
This paper describes a single-element planar focusing ultrasonic transducer with electrically tunable focal size, through modifying the design of a self-focusing acoustic transducer (SFAT). The transudcer is built on a 1-mm-thlck lead zirconate titanate (PZT) with (1) Fresnel acoustic lens formed with annular rings of air cavities on the top and (2) patterned annular ring electrodes on the bottom. By controlling the number of Fresnel rings being driven from the center, we were able to tune the focal size between 371 and 866 µm, while keeping the focal length at 6 mm, with 2.32 MHz pulsed ultrasound. When tested as a droplet ejector, the transducer ejected water droplets with diameter between 294 and 560 µm (between 13.3 and 92.0 nL in volume), depending on which set of electrodes are actuated.