Date of Award
1-1-2025
Document Type
Dissertation
Degree Name
Ph.D. in Physics
First Advisor
Joel Mobley
Second Advisor
Cecille Labuda
Third Advisor
Jake Bennett
School
University of Mississippi
Relational Format
dissertation/thesis
Abstract
This dissertation investigates the design, analysis, and optimization of tunable acoustic lenses with a primary focus on beamforming, dynamic focusing, and the generation of limited diffraction beams. The study examines the performance of four-channel and six-channel lenses in producing highly controlled ultrasonic fields with minimal diffraction. Numerical simulations and experimental validation are used to demonstrate how these lenses effectively form focused beams that maintain spatial coherence over a range of distances.
A systematic comparison between the four-channel and six-channel lenses is performed at multiple focal configurations (5.5 cm, 7.8 cm, and 10.0 cm). The results show that both lens types successfully generate limited diffraction beams comparable to the fraxicon, with the six-channel lens offering superior performance in terms of beam quality, dynamic focusing, and focal accuracy. The analysis of longitudinal beam profiles confirms that the six-channel lens maintains beam coherence over extended focal ranges, reinforcing its efficacy for applications requiring precise and stable beam delivery.
In addition to generating limited diffraction beams, the study also explores the secondary capability of the lenses to create stable trapping zones, demonstrating their potential for particle manipulation in the nearfield. While the trapping performance is not as pronounced as the beamforming capabilities, the six-channel lens exhibits strong and stable trapping regions, offering versatility for biomedical and acoustofluidic applications.
Overall, this dissertation provides a comprehensive framework for understanding and optimizing tunable acoustic lenses for producing limited diffraction beams, dynamic focusing, and particle manipulation. The demonstrated advancements in beamforming performance and particle trapping and manipulation highlight the potential of these lenses for a range of applications, including acoustic imaging, targeted drug delivery, and microfluidic systems. Future work may focus on refining lens design to enhance both trapping stability and beam quality for even broader practical use.
Recommended Citation
Rostami, Sina, "The characterization of radiation forces using tunable acoustic lenses" (2025). Electronic Theses and Dissertations. 3372.
https://egrove.olemiss.edu/etd/3372