Fiber Optic Sensors for Distributed and Quasi-distributed Temperature Measurement

This work evaluates the performance of distributed fiber optic based-sensors during laser-induced hyperthermia in tissues-simulating phantoms. Standard single-mode Corning SMF-28 and LUNA high definition fiber optic sensor (HD-FOS) were used for distributed sensing with LUNA ODiSI-B interrogator. The performance of the sensors for a one-and two-dimensional temperature reconstruction was investigated. Also, the effect of LUNA ODiSI-B's gauge length (GL) parameter on temperature reconstruction was assessed during this study. Temperature measurements of fiber Bragg grating array of 10 gratings were used as a reference. The obtained results show that temperature is significantly underestimated with high GL value (peak difference more than 12.0 °C), and smaller GL yields to more accurate temperature reconstruction for the HD-FOS fiber (peak difference <1.7 °C). The outcome of this analysis highlights the relevance of the sensors' length and characteristics for accurate temperature monitoring in temperature gradient conditions, towards a proper selection of the adequate sensing system.