A fiber laser temperature sensor based on SMF core-offset structure

A simple and low cost fiber laser temperature sensor based on all-fiber single-mode core-offset structure has been demonstrated. When temperature is applied on the core-offset structure filter, the pass-band varies and the wavelength of the output laser shifts correspondingly. A good temperature sensitivity of 0.0449 nm/°C and a detection limit of 0.42 °C are achieved with measuring range from 30 °C to 270 °C. Compared with the conventional temperature sensing system, a 980 nm laser diode is used as the light source and less detection limit, higher output power and the side-mode suppression ratio (SMSR) are obtained by the proposed fiber laser sensor.