How digital holography builds bridges for interdisciplinary research

Pascal PICART; Le Mans Université, France

E-Mail: Pascal.Picart@univ-lemans.fr

Abstract:

We aim at discussing the crucial role of photonics in inter-disciplinary science; In this talk we will focus on the case of digital holography and its connection with research in animal behavior science. Considering the question of binaural cues of tetrapod, Lord Rayleigh, in 1875, demonstrated the sound localization of tetrapod is closely depending on their head size and acoustic wavelength range: big tetrapod should localize sound in the low frequency range whereas small tetrapod should localize sound for higher frequencies. However, in nature, a few singularities do exist, especially with the species of anurans. Anurans are considered as the most vocal of vertebrates. Indeed, they use acoustic communication in many behavioral contexts, even in their reproduction process. From the point of view of frequency and size, most anuran species have dominant frequencies of a few thousand hertz and small size from around 10 mm to 50 mm. We aim at taking the benefits of holography to in-vivo investigate mechano-acoustic response of such animals. Thus, we propose a methodological breakthrough for the study of anuran hearing by considering, on one hand, innovative imaging methods, and on the other hand, with numerical modeling to provide a non-invasive understanding of these hearing structures. 
In this talk, we will present the different approaches we developed, both with the experimental side, with holographic imaging, and numerical modeling, to provide a non-invasive understanding of hearing structures. Those works include the measurement of tympanic membranes of live specimen with excitation in range 1000Hz-3000Hz, holographic imaging by achiral digital holography, the estimation of amplitude & phase of left & right tympanic vibrations, the extraction of quantitative metrics, the internal ear scanned by 3D x-ray micro-tomography, the mesh 3D data for Finite Element Methods, the simulation of acoustic excitation to evaluate acoustic pressure at tympanic membranes, the correlation with experiments.

Bio:

Pascal Picart is a Professor at Le Mans Université, France. He graduated from the École Supérieure d’Optique in 1992 and received his PhD in physics from the University of Paris XI, Orsay, France, in 1995. He joined Le Mans University in 1996. He is the author of 120 journal papers, 30 invited talks, more than 180 proceedings in international & national conferences, 7 book chapters, coordinated 4 books and co-founded one start-up. His research topics are connected with coherent imaging based on digital holography and its various applications to acoustics, mechanics and fluid mechanics.
Pascal Picart is member of the OPTICA (formerly OSA), SPIE, Société Française d’Optique (SFO), and the European Optical society (EOS). Pascal Picart is Fellow OPTICA.