Tip optical fiber refractive index sensor based on a thin copper film


  • Y. Lopez-Dieguez Tecnológico de Estudios Superiores de Ixtapaluca
  • J. M. Estudillo-Ayala Universidad de Guanajuato
  • D. Jáuregui Vázquez Universidad de Guanajuato
  • L. A. Herrera-Piad Universidad de Guanajuato
  • J. A. Martín-Vela Universidad de Guanajuato
  • J. M. Sierra-Hernandez Universidad de Guanajuato
  • J. C. Hernandez-Garcia Universidad de Guanajuato
  • M. Bianchetti Universidad de Guanajuato
  • M. Avazpour Universidad de Guanajuato
  • R. Rojas-Laguna Universidad de Guanajuato




Fiber optic sensor, Modal Fiber Optic Interferometer, Liquid Concentration Measurement



We report a refractive index tip fiber optic sensor based on a modal interferometer coated with a thin copper film. This device can be used for solute concentration in aqueous mixture measurement. The copper film increases the device reflectivity and, as a result, increases the multimodal interference pattern visibility. To validate the sensor device, different water-glycerol weight concentrations were used in the range from 0 to 45 Glycerol %. The recorded spectral responses show a redshifting, and a sensitivity of 19 pm / (Glycerol % by weight) from 0 to 18 % and 4.7 pm / (Glycerol % by weight) from 18 to 45 % was achieved. Besides, using a phase analysis we calculated a sensitivity of -15 rad/RIU.


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How to Cite

Lopez-Dieguez Y, Estudillo-Ayala JM, Jáuregui Vázquez D, Herrera-Piad LA, Martín-Vela JA, Sierra-Hernandez JM, Hernandez-Garcia JC, Bianchetti M, Avazpour M, Rojas-Laguna R. Tip optical fiber refractive index sensor based on a thin copper film. Supl. Rev. Mex. Fis. [Internet]. 2021 Mar. 31 [cited 2022 Oct. 4];2(1 Jan-Mar):43-8. Available from: https://rmf.smf.mx/ojs/index.php/rmf-s/article/view/5603