A CONCATENATED UP AND DOWN TAPERED FIBER FOR SIMULTANEOUS MEASUREMENT OF STRAIN AND TEMPERATURE

Öz A novel fiber optical sensor based on in-line fiber Mach-Zehnder interferometer for simultaneous measurement of strain and temperature is proposed and demonstrated experimentally. The interferometer is simple, extremely robust and highly sensitive and consists of two concatenated parts; one is a down-tapered fiber (DTF) and the other is an up-tapered fiber (UTF). UTF and DTF sections of the sensor are fabricated by using a commercial fiber splicer and a non-commercial setup based on heating and stretching a portion of a standard single-mode fiber, respectively. While UTF section behaves as a beam splitter to decompose the injected light into core and cladding modes, DTF section provides evanescent field to access the surrounding environment. Experimental results indicate that the resolutions of 0.83 °C and 45.80 micro-epsilon were achieved in temperature and strain, respectively, for simultaneous measurement with a 10 pm of wavelength resolution.

___

Sun, H., Yang, S., Zhang, X., Yuan, L., Yang, Z., Hu, M., Simultaneous measurement of temperature and strain or temperature and curvature based on an optical fiber Mach-Zehnder interferometer, Opt. Comm., 340 (2015), 39-43.

Zhou, D. P., Wei, L., Liu, W. K., Liu, Y., Lit, J. W. Y., Simultaneous measurement for strain and temperature using fiber Bragg gratings and multimode fibers, App. Optics., 47 (2008) 1668-72.

Jiang, N., Zhu, H., Bao, K., Hu, Y., Simultaneous discrimination of strain and temperature using dual-gratings in one fiber, Optik, 126 (2015) 3974-7

Yang, W., Geng, T., Yang, J., Zhou, A., Zhaojun, L., Geng S., Yuan, L., A phase-shifted long period fiber grating based on filament heating method for simultaneous measurement of strain and temperature, J. Opt., 17 (2015), 1-6.

Yoon, M. S., Park, S., Han, Y. G., 2012 Simultaneous measurement of strain and temperature by using a micro-tapered fiber grating, J. Ligh. Tech., 30 () 1156-60

Li, J., Yang, S., Zhang, W., Gao, S., Bai, Z., Wang, L., Liang, H., Yan, T., Simultaneous force and temperature measurement using S fiber taper in fiber Bragg grating, IEEE Phot. Tech. Lett., 26 (2014), 309-312.

Chu, J., Shen, C., Qjan, F., Zhong, C., Zou, X., Dong, X., Jin, Y., Wang, J., Gong, Y., Jiang, T., Simultaneous measurement of strain and temperature based on a long-period grating with a polarization maintaining fiber in a loop mirror, Opt. Fib. Tech., 20 (2014), 44-47.

Frazao, O., Marques, L. M., Santos, S., Baptista, J. M., Santos, J. L., Simultaneous measurement for strain and temperature based on a long-period grating combined with a high-birefringence fiber loop mirror, IEEE Phot. Tech. Lett., 18 (2006), 2407-2409.

Chen, H. F., Wang, D. N., Wang, Y., Simultaneous strain and temperature sensing using a slightly tapered optical fiber with an inner cavity, Analyst, 140 (2015), 1859-1862.

Dong, B., Peng, Y., Wang, Y., Yu, C., Mode division multiplexing in a fiber modal interferometer for dual-parameters measurement, IEEE Phot. Tech. Lett., 28 (2016), 143-146.

Zhou, J., Liao, C., Wang, Y., Yin, G., Zhong, X., Yang, K., Sun, B., Wang, G., Li, Z., Simultaneous measurement of strain and temperature by employing fiber Mach-Zehnder interferometer, Opt. Exp., 22 (2014), 1680-1686.

Andre, R. M., Biazoli, C. R., Silva, S. O., Marques, M. B., Cordeiro, C. M. B., Frazao, O., Strain-temperature discrimination using multimode interference in tapered fiber, IEEE Phot. Tech. Lett., 25 (2013), 155-158.

Zhang, C., Lu, P., Liao, H., Ni, W., Fu, X., Jiang, X., Liu, D., Zhang, J., Simultaneous measurement of axial strain and temperature based on a Z-Shape fiber structure, IEEE Phot. J., 9 (2017), 1-9.

Navruz, I., Ari, F., Bilsel, M. and AL-Mashhadani, Z. A., Enhancing refractive index sensitivity using micro-tapered long-period fiber grating inscribed in biconical tapered fiber, Opt. Fib. Tech., 45 (2018), 201-207.

Chen, L. X., Huang, X. G., Li, J. Y., Zhong, Z. B., Simultaneous measurement of refractive index and temperature by integrating an external Fabry-Perot cavity with a fiber Bragg grating, Rev. Sci. Inst., 83 (2012), 053113.

Han, K. J., Lee, Y. W., Kwon, J., Roh, S., Jung, J., Lee, B., Simultaneous measurement of strain and temperature incorporating a long-period fiber grating inscribed on a polarization maintaining fiber, IEEE Phot. Tech. Lett., 16 (2004), 2114-2116.

Qi, T., Xiao, S., Shi, J., Zhou, Z., Bi, M., Li, P., Simultaneous strain and temperature measurement using compact core-offset inter-modal interferometer with embedded fiber Bragg grating, Asia Communications and Photonics Conference ACP, Guangzhou, China (2012).