@ARTICLE{10.21494/ISTE.OP.2025.1347, 

TITLE={Temperature measurement in semi-transparent media by transmission photothermal heterodyne imaging}, 
  
AUTHOR={Jordan Letessier
, Jérémie Maire
, Stéphane Chevalier, }, 
	
JOURNAL={Entropy: Thermodynamics – Energy – Environment – Economy }, 
	
VOLUME={6}, 

NUMBER={Special Issue}, 
	
YEAR={2025}, 

URL={https://www.openscience.fr/Temperature-measurement-in-semi-transparent-media-by-transmission-photothermal}, 
	
DOI={10.21494/ISTE.OP.2025.1347}, 
	
ISSN={2634-1476}, 
	
ABSTRACT={Measuring temperature fields in semi-transparent media requires the knowledge of optothermal properties. While current techniques are well established for isothermal thin films, they remain unexplored for thick films with temperature gradients. This study proposes to generalize current methods to thick media by combining transmittance measurement based on transmission heterodyne photothermal imaging (TPHI) and optothermal modeling. In this work, we demonstrate the validity of our model, followed by the measurements of thermotransmittance and thermoreflectance coefficients for 3 different materials.}}