title: Design of Fresnel Lens-Type Multi-Trapping Acoustic Tweezers.
abstract: In this paper, acoustic tweezers which use beam forming performed by a Fresnel zone plate are proposed. The performance has been demonstrated by finite element analysis, including the acoustic intensity, acoustic pressure, acoustic potential energy, gradient force, and particle distribution. The acoustic tweezers use an ultrasound beam produced by a lead zirconate titanate (PZT) transducer operating at 2.4 MHz and 100 Vpeak-to-peakin a water medium. The design of the Fresnel lens (zone plate) is based on air reflection, acoustic impedance matching, and the Fresnel half-wave band (FHWB) theory. This acoustic Fresnel lens can produce gradient force and acoustic potential wells that allow the capture and manipulation of single particles or clusters of particles. Simulation results strongly indicate a good trapping ability, for particles under 150 µm in diameter, in the minimum energy location. This can be useful for cell or microorganism manipulation.
authors.affiliation: Department of Mechanical Engineering, National Central University, Taoyuan 32001, Taiwan. 104323074@cc.ncu.edu.tw.
authors.forename: You-Lin
authors.initials: YL
authors.lastname: Tu
authors.affiliation: Department of Mechanical Engineering, National Central University, Taoyuan 32001, Taiwan. raychen@cc.ncu.edu.tw.
authors.forename: Shih-Jui
authors.initials: SJ
authors.lastname: Chen
authors.affiliation: Department of Mechanical Engineering, National Central University, Taoyuan 32001, Taiwan. yhwang@cc.ncu.edu.tw.
authors.forename: Yean-Ren
authors.initials: YR
authors.lastname: Hwang
keywords: Fresnel lens; acoustic tweezers; particle trapping