Detection of thermal gradients through fiber-optic Chirped Fiber Bragg Grating (CFBG): Medical thermal ablation scenario

Sanzhar Korganbayev, Yerzhan Orazayev, Sultan Sovetov, Ali Bazyl, Emiliano Schena, Carlo Massaroni, Riccardo Gassino, Alberto Vallan, Guido Perrone, Paola Saccomandi, Michele Arturo Caponero, Giovanna Palumbo, Stefania Campopiano, Agostino Iadicicco, Daniele Tosi

Research output: Contribution to journalArticle

17 Citations (Scopus)


In this paper, we describe a novel method for spatially distributed temperature measurement with Chirped Fiber Bragg Grating (CFBG) fiber-optic sensors. The proposed method determines the thermal profile in the CFBG region from demodulation of the CFBG optical spectrum. The method is based on an iterative optimization that aims at minimizing the mismatch between the measured CFBG spectrum and a CFBG model based on coupled-mode theory (CMT), perturbed by a temperature gradient. In the demodulation part, we simulate different temperature distribution patterns with Monte-Carlo approach on simulated CFBG spectra. Afterwards, we obtain cost function that minimizes difference between measured and simulated spectra, and results in final temperature profile. Experiments and simulations have been carried out first with a linear gradient, demonstrating a correct operation (error 2.9 °C); then, a setup has been arranged to measure the temperature pattern on a 5-cm long section exposed to medical laser thermal ablation. Overall, the proposed method can operate as a real-time detection technique for thermal gradients over 1.5–5 cm regions, and turns as a key asset for the estimation of thermal gradients at the micro-scale in biomedical applications.
Original languageEnglish
Pages (from-to)48 - 55
Number of pages8
JournalOptical Fiber Technology
Publication statusPublished - 1 Mar 2018
Externally publishedYes


All Science Journal Classification (ASJC) codes

  • Electronic, Optical and Magnetic Materials
  • Electrical and Electronic Engineering

Cite this

Korganbayev, S., Orazayev, Y., Sovetov, S., Bazyl, A., Schena, E., Massaroni, C., Gassino, R., Vallan, A., Perrone, G., Saccomandi, P., Arturo Caponero, M., Palumbo, G., Campopiano, S., Iadicicco, A., & Tosi, D. (2018). Detection of thermal gradients through fiber-optic Chirped Fiber Bragg Grating (CFBG): Medical thermal ablation scenario. Optical Fiber Technology, 41, 48 - 55.