Open AccessMulti-phase-shifted helical long period fiber grating based temperature-insensitive optical twist sensor
Author(s) -
Ran Gao,
Yuan Jiang,
Lan Jiang
Publication year - 2014
Publication title -
optics express
Language(s) - Uncategorized
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.22.015697
Subject(s) - materials science , optics , long period fiber grating , grating , fiber bragg grating , fiber optic sensor , wavelength , dispersion shifted fiber , optical fiber , phase (matter) , graded index fiber , twist , optoelectronics , physics , geometry , mathematics , quantum mechanics
A compact temperature-insensitive optical fiber twist sensor based on multi-phase-shifted helical long period fiber grating has been proposed and experimentally demonstrated in this paper. A multi-phase-shifted helical long period fiber grating is fabricated with a multi-period rotation technology. A π/2 and a 3π/2 phase shift is introduced in the helical long period fiber grating by changing the period. The helical pitch can be effectively changed with a different twist rate, which is measured by calculating the wavelength difference between two phase shift peaks. Although the wavelength of the phase shift peak also shifts with a change of the temperature, the wavelength difference between two phase shift peaks is constant due to two fixed phase shifts in the helical long period fiber grating, which is extremely insensitive to temperature change for the multi-phase-shifted helical long period fiber grating. The experimental results show that a sensitivity of up to 1.959 nm/(rad/m) is achieved.