TY - JOUR
T1 - Bragg Gratings in Two-Core Rectangular Fiber for Discrimination of Curvature, Strain, and Temperature Measurements
AU - Htein, Lin
AU - Gunawardena, Dinusha Serandi
AU - Leong, Chern Yang
AU - Tam, Hwa Yaw
N1 - Funding Information:
Manuscript received August 15, 2020; revised October 2, 2020; accepted October 21, 2020. Date of publication November 3, 2020; date of current version January 5, 2021. This work was supported by in part by The Hong Kong Polytechnic University (Project 1-ZVGB), in part by the CNERC Project BBVH, and in part by the National Natural Science Foundation of China (NSFC) under Grant 61827820 and Grant 61905096. The Associate Editor coordinating the review process was Dr. Yuya Koyama. (Corresponding author: Dinusha Serandi Gunawardena.) Lin Htein, Dinusha Serandi Gunawardena, and Chern Yang Leong are with the Photonics Research Centre, Department of Electrical Engineering, The Hong Kong Polytechnic University, Hong Kong, China (e-mail: [email protected]; [email protected]; [email protected]).
Publisher Copyright:
© 1963-2012 IEEE.
PY - 2020/11/3
Y1 - 2020/11/3
N2 - We report, for the first time, the development of a rectangular fiber with two cores consisting of different refractive indices for the discrimination of temperature effects during strain or curvature measurements using fiber Bragg gratings written in a single segment of fiber. Two cores with a diameter of 8~\mu \text{m} and a rectangular cladding with dimensions of 120\,\,\mu \text{m} \times 255\,\,\mu \text{m} permit convenient splicing to conventional single-mode fiber and support easy identification of the orientation of the fiber. When placed in the desired orientation, each core of the two-core rectangular fiber experiences a different spectral shift in the presence of applied strain or curvature. The sensitivities of the two cores are 0.87 and 1.08 pm/ \mu \varepsilon for strain, 126 and -128 pm/m-1 for curvature, and 10.05 and 10.40 pm/°C for temperature, respectively. In addition, the flat cladding structure of the fiber provides a large physical contact area between the sensing fiber and the substrate than a circular fiber and allows better strain coupling between the object and the fiber.
AB - We report, for the first time, the development of a rectangular fiber with two cores consisting of different refractive indices for the discrimination of temperature effects during strain or curvature measurements using fiber Bragg gratings written in a single segment of fiber. Two cores with a diameter of 8~\mu \text{m} and a rectangular cladding with dimensions of 120\,\,\mu \text{m} \times 255\,\,\mu \text{m} permit convenient splicing to conventional single-mode fiber and support easy identification of the orientation of the fiber. When placed in the desired orientation, each core of the two-core rectangular fiber experiences a different spectral shift in the presence of applied strain or curvature. The sensitivities of the two cores are 0.87 and 1.08 pm/ \mu \varepsilon for strain, 126 and -128 pm/m-1 for curvature, and 10.05 and 10.40 pm/°C for temperature, respectively. In addition, the flat cladding structure of the fiber provides a large physical contact area between the sensing fiber and the substrate than a circular fiber and allows better strain coupling between the object and the fiber.
KW - Bragg gratings
KW - curvature
KW - flat cladding
KW - rectangular fiber
KW - sensor
KW - strain
KW - temperature
UR - https://www.scopus.com/pages/publications/85098850562
U2 - 10.1109/TIM.2020.3035528
DO - 10.1109/TIM.2020.3035528
M3 - Journal article
AN - SCOPUS:85098850562
SN - 0018-9456
VL - 70
JO - IEEE Transactions on Instrumentation and Measurement
JF - IEEE Transactions on Instrumentation and Measurement
M1 - 9247138
ER -