In this paper, acoustic tweezers which use beam forming performed by a Fresnel zone plate\nare proposed. The performance has been demonstrated by finite element analysis, including the\nacoustic intensity, acoustic pressure, acoustic potential energy, gradient force, and particle distribution.\nThe acoustic tweezers use an ultrasound beam produced by a lead zirconate titanate (PZT) transducer\noperating at 2.4 MHz and 100 Vpeak-to-peak in a water medium. The design of the Fresnel lens\n(zone plate) is based on air reflection, acoustic impedance matching, and the Fresnel half-wave band\n(FHWB) theory. This acoustic Fresnel lens can produce gradient force and acoustic potential wells\nthat allow the capture and manipulation of single particles or clusters of particles. Simulation results\nstrongly indicate a good trapping ability, for particles under 150 �¼m in diameter, in the minimum\nenergy location. This can be useful for cell or microorganism manipulation.
Loading....