Temperature Sensing Characteristics of Improved SNCS Fiber Sensor

For optical fiber sensor with single-mode-no-core-single-mode (SNCS) structure, the basic principle of SNCS structure sensing is to change the mode field distribution of SNCS structure by changing the refractive index distribution of the structure. The sensitivity can be improved by optimizing the structure or changing the material of the sensitive region. In this paper, the effects of structural parameters and assembly materials on the sensitivity of SNCS optical fiber sensor are studied by far from the cut-off condition. The correctness of these conclusions is verified by experiments. For the temperature sensor, the material with large thermal optical coefficient (TOC) can be used as the cladding or fiber core to improve the sensitivity of the sensor. These conclusions provide some reference for the design and assembly of temperature sensor with SNCS structure.