| Title |
A Study on Separate Measurement of Curvature and Temperature using Fiber Transmission Grating Fabricated on High Birefringence Fiber |
| Authors |
Jinsil Han ; Yong Wook Lee |
| DOI |
http://dx.doi.org/10.5207/JIEIE.2019.33.8.039 |
| Keywords |
High Birefringence Fiber; Fiber Transmission Grating; Separate Measurement; Curvature; Temperature |
| Abstract |
In this study, we propose an optical fiber sensor capable of separately measuring curvature and temperature by utilizing a fiber transmission grating(FTG) written on high birefringence fiber(HBF) with a CO2 laser. By fabricating an FTG on HBF(HB-FTG), two resonance dips A and B with different wavelengths of 1480.0 and 1568.8nm could be obtained, respectively, for two orthogonal input polarization states. The bending sensitivities of the two resonance dips A and B of the HB-FTG were measured to be 23.70 and 34.44nm/m-1 in a curvature range from 1.41 to 2.30m-1, and their adjusted R2 values representing the linearity of the sensor response were evaluated as 0.992 and 0.981, respectively. When the ambient temperature of the HB-FTG changed from 35 to 85°C by a step of 10°C, the temperature sensitivities of the dips A and B were measured to be 0.141 and 0.038nm/°C, and the R2 values were evaluated as 0.988 and 0.997, respectively. Using these pre-calculated four sensitivity coefficients and linearity of bending and temperature sensitivities measured in two resonance dips, the possibility of separate measurement of bending and temperature applied to the HB-FTG was presented. |