On Nov.7, Prof. Mathias Fink -- the world well-known physicians visited IACAS and gave a brilliant academic lecture titled "Imaging Elasticity of Human Body: Multi-wave examples".

Mathias Fink is a Professor of Physics at the Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI) and at Paris 7 University (Denis Diderot), France. In 1990 he founded the laboratory Ondes et Acoustique at ESPCI. In 2002, he was elected at the French Academy of Technology and in 2003 at the French Academy of Science. His current research interests include medical ultrasonic imaging, ultrasonic therapy, nondestructive testing, underwater acoustics, active control of sound and vibration, analogies between Optics and Acoustics, wave coherence in multiply scattering media and time reversal in physics. He has developed different techniques in wave focusing in inhomogeneous media, speckle reduction, and in ultrasonic laser generation. He holds 40 patents and has published 2 works and more than 300 articles.

In his lecture, Prof. Mathias Fink mainly talked about his research work on s-wave imaging in human body. Generally speaking, compressional wave is often used in traditional imaging. But when there are some pathological changes happened in the body, shear modulus will have a more obvious change than the compression modulus. Using shear modulus in imaging will be earlier to see the changes in human tissues. So he said we could design a new kind of transducer, which could generate s-wave in the body and we could get the shear modulus by the inversion of s-wave. In this way, we could get the image of high contrast ratio. Prof. Mathias Fink also reminded the audience that the s-wave in human body is frequency dispersive, so more attention should be paid to this point. Furthermore, Prof. Mathias Fink gave some practical examples of imaging of eyeball and muscle by s-wave and put forwarded the new idea to combine several imaging methods with s-wave in order to improve both the contrast ratio and the spatial resolution.　 　

The lecture of Prof. Mathias Fink brought in an innovative view which aroused great interests of students and many researchers. After the lecture, the researchers of IACAS had a discussion with Prof. Mathias Fink on the potential bilateral cooperation.