[16a-1E-1~11] 3.8 Optical measurement, instrumentation, and sensor

△ [16a-1E-7] Temperature sensing based on modal interference in plastic optical fibers: significantly improved sensitivity at high temperature

〇Goki Numata¹, Neisei Hayashi¹, Marie Tabaru¹, Yosuke Mizuno¹, Kentaro Nakamura¹ (1.Tokyo Tech)

Keywords:multimode interference,optical fiber sensors,plastic/polymer optical fibers

We have reported that temperature sensors based on modal interference in perfluorinated graded-index plastic optical fibers (POFs) show the world’s highest temperature sensitivity of +49.8 nm/°C/m at 1300 nm at room temperature, which is >1800 times the value in silica multimode fibers. Here, we find that the temperature sensitivity is significantly enhanced with increasing temperature toward ~70°C (close to the glass-transition temperature of the core polymer). With 62.5-μm core diameter, the sensitivity at 72 °C at 1300 nm is +202 nm/°C/m, ~26 times the value at room temperature and >7000 times the highest value previously reported using a silica fiber.