Simultaneous measurement of strain and temperature based on pure-silica-core fiber and no-core fiber

Abstract. We propose and demonstrate an all-fiber sensor for simultaneous measurement of strain and temperature that is based on a no-core fiber (NCF) and pure-silica-core fiber (PSCF). Two segments of NCF used as a beam splitter and combiner were embedded on the two ends of the PSCF, which constitutes a Mach–Zehnder interferometer (MZI) susceptible to the strain and temperature. With the change of strain and temperature, the dip wavelengths of transmission spectrum shifted, and simultaneous measurement of strain and temperature was realized by means of a sensitivity coefficient matrix. The experimental results showed that the sensitivity of strain was −0.6 and   −  0.9  pm  /  με in the range from 0 to 1000  με, and the sensitivity of temperature ranging from 20°C to 80°C was 16.9 pm/°C and 11.7 pm/°C, respectively. Furthermore, the fiber sensor processed the advantages of easy-fabrication, compactness, low cost, and all-fiber configuration, and it has potential applications in blade load and damage monitoring in the field of wind power generation.