Application of the probe beam deflection technique in photoacoustic and ultrasound imaging

Date
2014
Authors
Barnes, Ronald
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract

Ultrasound imaging and Photoacoustic imaging methodologies, commonly utilize piezo-electric transducers, both ceramic-based and polymer-based, to detect the acoustic energy reflected or emitted from an imaging target. Ceramic based piezo-electric transducers, exhibit non-desirable traits including: limited bandwidth (<15 MHz), off-axis energy acceptance, and requirement of a perfectly matched layer (PML), due to the large impedance mismatch to soft tissue. Polymer based piezo-electric transducers such as PVDF, exhibit high bandwidth (up to 100 MHz), however exhibit low coupling efficiency (<0.2). An optical sensing method known as the Probe Beam Deflection Technique (PBDT), is applied to ultrasound and photoacoustic imaging, to detect the acoustic reflection/emission in ultrasound and photoacoustic imaging. It is shown that the PBDT exhibits: high bandwidth (>30 MHz), acoustic propagation directionality quantification, passive sensing, high coupling efficiency (>0.5) and impedance similar to soft tissue. A series of 2-D and 3-D ultrasound images are reconstructed utilizing the PBDT and compared to images reconstructed from piezo-electric transducers. It is shown that artifact reduction and improved contrast are exhibited by the PBDT.

Description
This item is available only to currently enrolled UTSA students, faculty or staff.
Keywords
Imaging artifacts, Laser deflection, Off-axis ultrasound, Photoacoustic imaging, Ultrsound imaging, Ultrasound transducers
Citation
Department
Electrical and Computer Engineering