Advancing electromagnetic imaging through ASEM technology

Advancements in Acoustically Stimulated ElectroMagnetic (ASEM) imaging have introduced a novel approach for visualizing electrical and magnetic properties within material and biological tissues. Traditionally, ultrasound modalities have been limited to mechanical property detection; however, the integration of electromagnetic responsiveness into ultrasonic interrogation marks a significant paradigm shift in material characterization. This lecture outlines the technological evolution of ASEM method, focusing on its capability to quantify and spatially map piezoelectric properties of biological soft tissues, as well as piezomagnetic characteristics of materials such as steel. We explore the foundational principles that enabled the fusion of acoustic and electromagnetic domains, along with key innovations in probe design, signal processing, and modeling techniques. Through a series of experimental studies and clinical prototypes, we demonstrate how ASEM method has evolved from early-phase phantom testing to in situ evaluations in nondestructive testing and clinical diagnostics.