Composite ultrasound transducer for multi-size of tweezer manipulation

The application of acoustic tweezers in many fields has driven the innovation of device optimization, such as cell characterization and manipulation, drug extraction and movement. The current application of acoustic tweezers faces certain challenges because it does not enable the capture of multi-size particles. In order to improve the adaptability of acoustic tweezers and overcome the forbidden band of radiation force trapping, this paper presents the optimizer design, modeling and implementation of an acoustic tweezer with high sensitivity and broad bandwidth. The acoustic focusing beam and length between the numerical results and experimental results show fair agreements. Particularly, the acoustic radiation force on the elastic sphere with a diameter from 100 to 500 lm is calculated at 3.5 MHz, 5.5 MHz, 7.5 MHz, and 9.5 MHz. Experimental particle trapping demonstrates the effective trapped size range from 100 to 400 lm, which verifies the calculation of acoustic radiation force. The results show this transducer achieves a good focusing effect in a wide frequency band which realizes multi-dimensional control of particles in water at different working frequencies. In the future, this research for novel acoustic tweezers has great potential and value for industrial, chemical, medical and biological applications.(c) 2022 Published by Elsevier Ltd.