Vol. 108

Front:[PDF file] Back:[PDF file]
Latest Volume
All Volumes
All Issues

Simultaneous Measurement of Curvature and Temperature Based on a Simple Cascaded Fiber Interferometer

By Fang Wang, Yinghui Lu, and Yufang Liu
Progress In Electromagnetics Research M, Vol. 108, 151-161, 2022


An optical fiber sensor based on thin-core fiber (TCF) and no-core fiber (NCF) interference structures is presented and experimentally demonstrated to measure the curvature and temperature. The fabrication process of the sensor is simple and convenient, and the sensing part is formed by cascading a TCF and an NCF between two single-mode fibers. The dips at resonant wavelengths are generated in the optical transmission spectrum owing to mode interference. The experimental results indicate that an optical curvature sensitivity of -5.76 nm/m-1 is achieved in the linear range of 0.9895-3.2817 m-1, and that a temperature sensitivity of 0.18 nm/˚C is obtained in the temperature range of 25-55˚C. Additionally, the cross-sensitivity problem is solved using the coefficient matrix measurement method, and the cross-sensitivity is as low as 0.0312 m-1/˚C. Therefore, the sensor exhibits a highly reproducible technique and low cross sensitivity, which has a wide range of application prospects in the accurate measurement of mechanical arms and structural health monitoring.


Fang Wang, Yinghui Lu, and Yufang Liu, "Simultaneous Measurement of Curvature and Temperature Based on a Simple Cascaded Fiber Interferometer," Progress In Electromagnetics Research M, Vol. 108, 151-161, 2022.


    1. Jang, M., J. S. Kim, S. H. Um, S. Yang, and J. Kim, "Ultra-high curvature sensors for multi-bend structures using fiber Bragg gratings," Opt. Express, Vol. 27, No. 3, 2074-2084, Feb. 2019.

    2. Yang, W., C. Li, M. Wang, X. Yu, J. Fan, Y. Xiong, Y. Yang, and L. Li, "The polydimethylsiloxane coated fiber optic for all fiber temperature sensing based on the multi-thin-multi fiber structure," IEEE Sens. J., Vol. 21, No. 1, 51-56, Jan. 2020.

    3. Abbas, L. G., A. Zhou, F. Mumtaz, A. Muhammad, Y. Dai, and R. Parveen, "Temperature and strain sensing with hybrid interferometer," IEEE Sens. J., Vol. 21, No. 23, 26785-26792, Dec. 2021.

    4. Hou, Y., J. Wang, X. Wang, Y. Liao, L. Yang, E. Cai, and S. Wang, "Simultaneous measurement of pressure and temperature in seawater with PDMS sealed microfiber Mach-Zehnder interferometer," J. Lightwave Technol., Vol. 38, No. 22, 6412-6421, Nov. 2020.

    5. Azmi, A., A. Abdullah, M. Noor, M. Ibrahim, R. Ibrahim, T. Tan, and J. Zhang, "Dynamic bending and rotation sensing based on high coherence interferometry in multicore fiber," Opt. Laser Technol., Vol. 135, 106716, Mar. 2021.

    6. Zhang, X., B. Liu, H. Zhang, J. Wu, B. Song, and C. Wang, "A magnetic field sensor based on a dual S-tapered multimode fiber interferometer," Meas. Sci. Technol., Vol. 29, No. 7, 075103, Jul. 2018.

    7. Wang, F., K. Pang, T. Ma, X. Wang, and Y. Liu, "High-sensitivity and temperature-insensitive refractometer based on TNHF structure for low-range refractive index measurement," Progress In Electromagnetics Research, Vol. 166, 167-175, 2019.

    8. Chen, W., Z. Chen, Y. Zhang, and H. Li, "Fiber sensor for relative humidity measurement at water absorption band of 2 μm," Meas. Sci. Technol., Vol. 31, No. 3, 035101, Dec. 2019.

    9. Wang, F., L. Zhang, X. Wang, T. Ma, K. Yu, and Y. Liu, "A high-sensitivity sensor based on tapered dispersion compensation fiber for curvature and temperature measurement," Opt. Commun., Vol. 481, 126534, Oct. 2020.

    10. Zhao, Y., C. Cai, and X. Li, "Temperature-insensitive optical fiber curvature sensor based on SMF-MMF-TCSMFMMF-SMF structure," IEEE T. Instrum. Meas., Vol. 66, No. 1, 141-147, Jan. 2017.

    11. Zhou, Y., Y. Wang, H. Liu, J. Chen, P. Yang, L. she, F. Chen, J. Shao, Z. Guan, and Z. Zhang, "High-sensitive bending sensor based on a seven-core fiber," Opt. Commun., Vol. 483, 126617, Mar. 2021.

    12. Dong, S., B. Dong, C. Yu, and Y. Guo, "High sensitivity optical fiber curvature sensor based on cascaded fiber interferometer," J. Lightwave Technol., Vol. 36, No. 4, 1125-1130, Feb. 2018.

    13. Zhu, F., Y. Zhang, Y. Qu, W. Jiang, H. Su, Y. Guo, and K. Qi, "Stress-insensitive vector curvature sensor based on a single fiber Bragg grating," Opt. Fiber. Technol., Vol. 54, No. 102133, Jan. 2020.

    14. Fu, X., J. Wen, Y. Zhang, D. Wang, F. Liu, H. Xie, G. Fu, and W. Bi, "Experimental and theoretical analysis of curvature sensor based on cladding mode resonance with triple cladding quartz specialty fiber," Opt. Commun., Vol. 429, 5-11, Dec. 2018.

    15. Zhang, S., Y. Liu, H. Guo, A. Zhou, and L. Yuan, "Highly sensitive vector curvature sensor based on two juxtaposed fiber Michelson interferometers with Vernier-like effect," IEEE Sens. J., Vol. 19, No. 6, 2148-2154, Mar. 2019.

    16. Zhao, Y., A. Zhou, H. Guo, Z. Zheng, Y. Xu, C. Zhou, and L. Yuan, "An integrated fiber michelson interferometer based on twin-core and side-hole fibers for multiparameter sensing," J. Lightwave Technol., Vol. 36, No. 4, 993-997, Feb. 2018.

    17. Ruan, J., "Fiber curvature sensor based on concave-heterotypic cascaded fiber Sagnac interferometer," Microw. Opt. Techn. Let., Vol. 62, No. 11, 3645-3649, Nov. 2020.

    18. Wang, S., W. Zhang, L. Chen, Y. Zhang, P. Geng, Y. Zhang, T. Yan, L. Yu, W. Hu, and Y. Li, "Two-dimensional micro bend sensor based on long-period fiber gratings in an isosceles triangle arrangement three-core fiber," Opt. Lett., Vol. 42, No. 23, 4938-4941, Dec. 2017.

    19. Oliveira, R., J. Osorio, S. Aristilde, L. Bilro, R. Nogueira, and C. Cordeiro, "Simultaneous measurement of strain, temperature and refractive index based on multimode interference, fiber tapering and fiber Bragg gratings," Meas. Sci. Technol., Vol. 27, No. 7, 075107, Jul. 2016.

    20. Zhou, Y., W. Zhou, C. Chan, W. Wong, L. Shao, J. Cheng, and X. Dong, "Simultaneous measurement of curvature and temperature based on PCF-based interferometer and fiber Bragg grating," Opt. Commun., Vol. 284, No. 24, 5669-5672, Dec. 2011.

    21. Wo, J., Q. Sun, X. Li, D. Liu, and P. Shum, "Biconical-taper-assisted fiber interferometer with modes coupling enhancement for high-sensitive curvature measurement," Appl. Phys. B - Lasers O., Vol. 115, No. 1, 1-8, Apr. 2014.

    22. Sun, X., H. Du, X. Dong, Y. Hu, and J. Duan, "Simultaneous curvature and temperature sensing based on a novel Mach-Zehnder interferometer," Photonic Sens., Vol. 10, No. 2, 171-180, Jun. 2020.

    23. Gutiérrez Gutiérreza, J., J. Sierra-Hernandez, M, Vargas-Trevino, E. Lopez-Apreza, C. Romero-Salazar, O. Hernandez-Flores, J. Estudillo-Ayala, and R. Rojas-Laguna, "A curvature sensing setup based on an asymmetric concatenated tapered Mach-Zehnder interferometer," Opt. Laser Technol., Vol. 132, 106490, Dec. 2020.

    24. Chen, E., B. Dong, Y. Li, X. Wang, Y. Zhao, W. Xu, W. Zhao, and Y. Wang, "Cascaded few-mode fiber down-taper modal interferometers and their application in curvature sensing," Opt. Commun., Vol. 475, 126274, Nov. 2020.

    25. Cheng, H., S. Wu, Q. Wang, S. Wang, and P. Lu, "In-line hybrid fiber sensor for curvature and temperature measurement," IEEE Photon. J., Vol. 11, No. 6, 6803311, Dec. 2019.

    26. Zhao, Y., L. Cai, and X. Li, "High sensitive modal interferometer for temperature and refractive index measurement," IEEE Photonic Tech. L., Vol. 27, No. 12, 1341-1344, Jun. 2015.

    27. Yu, F., P. Xue, and J. Zheng, "Enhancement of refractive index sensitivity by bending a core-offset in-line fiber Mach-Zehnder interferometer," IEEE Sens J., Vol. 19, No. 9, 3328-3334, May 2019.

    28. Zhao, Y., M. Chen, F. Xia, L. Cai, and X. Li, "Small curvature sensor based on butterfly shaped Mach-Zehnder interferometer," IEEE T. Electron. Dev., Vol. 64, No. 11, 4644-4649, Nov. 2017.

    29. Zhang, Y., W. Zhang, Y. Zhang, S. Wang, L. Yu, and Y. Yan, "Simultaneous measurement of curvature and temperature based on LP11 mode Bragg grating in seven-core fiber," Meas. Sci. Technol., Vol. 28, No. 5, 055101, May 2017.

    30. Wang, Q. and Y. Liu, "Review of optical fiber bending/curvature sensor," Measurement, Vol. 130, 161-176, Dec. 2018.

    31. Zheng, Y., X. Yang, W. Feng, and W. Fan, "Optical fiber refractive index sensor based on SMF-TCF-NCF-SMF interference structure," Optik, Vol. 226, 169500, Jan. 2021.

    32. Lu, H., X. Wang, S. Zhang, F. Wang, and F. Liu, "A fiber-optic sensor based on no-core fiber and Faraday rotator mirror structure," Opt. Laser Technol., Vol. 101, 507-514, May 2018.

    33. Raji, Y. M., H. S. Lin, S. A. Ibrahim, M. R. Mokhtar, and Z. Yusoff, "Intensity-modulated abrupt tapered Fiber Mach-Zehnder Interferometer for the simultaneous sensing of temperature and curvature," Opt. Laser Technol., Vol. 86, 8-13, Dec. 2016.