Optical thickness of a plant leaf measured with THz pulse echoes
Abautret, Yannick, Dominique Coquillat, Myriam Zerrad, Ryad Bendoula, Gabriel Soriano, Daphné Héran, Bruno Grèzes-Besset, Frédéric Chazallet, and Claude Amra. “Optical thickness of a plant leaf measured with THz pulse echoes.” In Terahertz, RF, Millimeter, and Submillimeter-Wave Technology and Applications XIII, vol. 11279, p. 112790L. International Society for Optics and Photonics, 2020.
We analyze Terahertz (THz) echoes by reflection on a sunflower leaf in order to evaluate the internal leaf structure (geometry, complex indices and thicknesses). The analysis is based on the thin film multilayer formalism in time and frequency domains. A high agreement is emphasized between experiment and theory, and we evaluate how realistic the multilayer solution can be in regard to our knowledge related to the sunflower leaf. A test campaign is performed in Charles Coulomb laboratory, which is equipped with the THz spectrometer.