@article{Gravier:9175,
      recid = {9175},
      author = {Gravier, Laurent and Salvadé, Yves and Pidoux, Damien and  Maritz, Julien and Laratta, Marco},
      title = {Low-cost nanostructured thin films as covert laser  readable security tags for large-scale productions  tracking},
      journal = {Applied Nano},
      address = {2021-10},
      number = {ARTICLE},
      pages = {11 p.},
      abstract = {We report here the feasibility study of  anti-counterfeiting low-cost nanostructured flexible  security tags for the tracking of large-scale fabrication  products, such as pharmaceuticals or original equipment  manufacturers. The fabrication process makes use of the  mature nanotechnology called Template Synthesis to shape  thin track-etched polymer film into covert laser readable  tags, combining random self-organized structures with  organized patterns. Techniques are developed to drastically  limit the number of fabrication steps and keep fabrication  costs low, while opening to numerous adjustment parameters.  A dedicated, simple optical setup is presented, to capture  speckle images of such tags lightened up by light emitting  diodes or laser beams. Speckle images are analyzed in terms  of encoding parameters, found here quite numerous to ensure  a large coding range of large-scale production batches. We  particularly highlight ultra-dark areas in speckle images,  where nanowire structures completely inhibit speckle  patterns. This unique, high-contrast optical feature  addresses these low-cost nanostructured thin films to  provide a very promising solution for large-scale security  tags.},
      url = {http://arodes.hes-so.ch/record/9175},
      doi = {https://doi.org/10.3390/applnano2040023},
}