Fiber-Optic Temperature and Pressure Sensors Applied to Radiofrequency Thermal Ablation in Liver Phantom: Methodology and Experimental Measurements

Figure 18

Schematic of the fabrication technique for the EFPI/FBG probe. (a) Fabrication of an EFPI probe over a preinscribed FBG sensor. In the first step, the FBG is fabricated with phase-mask technique on a standard single-mode fiber [18]; then, the fiber is spliced to a hollow glass capillary, and the resulting structure is spliced to a multimode fiber serving as diaphragm. Finally, etching in hydrofluoric (HF) acid [19] reduced the diaphragm thickness for pressure sensitivity. (b) Fabrication of an EFPI probe with subsequent inscription of the FBG: in this case, the sensor is built as in (a), steps 2–4, and the FBG is inscribed on the sensor tip as in [20].

(a)

(b)