Open AccessBend monitoring and refractive index sensing using flat fibre and multicore Bragg gratings
Author(s) -
Christopher Holmes,
Sumiaty Ambran,
Peter Cooper,
A. S. Webb,
James C. Gates,
C.B.E. Gawith,
J.K. Sahu,
Peter G. R. Smith
Publication year - 2020
Publication title -
measurement science and technology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.48
H-Index - 136
eISSN - 1361-6501
pISSN - 0957-0233
DOI - 10.1088/1361-6501/ab8710
Subject(s) - fiber bragg grating , cladding (metalworking) , materials science , refractive index , optics , subwavelength diameter optical fibre , optical fiber , offset (computer science) , optoelectronics , computer science , physics , metallurgy , programming language
A planarized optical fibre designed for two-dimensional bend monitoring and external refractive index sensing is presented. The approach uses two single-mode waveguides each containing a set of spectrally multiplexed Bragg gratings. To achieve sensitivity to bending and external refractive index, the cladding material of the fibre is partially removed through physical machining. This acts to offset the neutral axis, increasing bend sensitivity, and exposes the evanescent field of the guided mode, permitting external refractive index monitoring. Through collective monitoring of the Bragg grating array, real time, multiparameter sensing is attainable, allowing new capability for intelligent monitoring.