Tilted fiber Bragg gratings: Principle and sensing applications

Abstract

In this paper, the mode coupling mechanism of tilted fiber Bragg gratings (TFBGs) is briefly introduced at first. And a general review on the fabrication, theoretical and experimental research development of TFBGs is presented from a worldwide perspective, followed by an introduction of our current research work on TFBGs at the Institute of Modern Optics, Nankai University (IMONK), including TFBG sensors for single-parameter measurements, temperature cross sensitivity of TFBG sensors, and TFBG-based interrogation technique. Finally, we would make a summary of the related key techniques and a remark on prospects of the research and applications of TFBGs.

Orthogonally polarized bright–dark pulse pair generation in mode-locked fiber laser with a large-angle tilted fiber grating

“…0 -tilted fiber grating has been proposed to be used as in-fiber polarizer for mode-locking [23,24]. LA-TFG, which is a type of tilted grating with tilted angle larger than 45 0 , has been employed previously as fiber sensors for strain, twist, loading, refractive index (RI) and liquid level [25][26][27][28][29]. Our used LA-TFG was inscribed in H 2 -loaded standard telecom fiber (SMF-28) by use of a frequency-doubled Ar + laser and the scanning mask technique.…”

Optical inclinometer based on a tilted fiber Bragg grating with a fused taper

“…Meanwhile, there still exists some backward propagating Bragg wavelength k Bragg . The Bragg wavelength k Bragg and cladding mode resonant wavelengths k i clad are satisfied with the following phase matching condition [14]: …”

Manufacturing and Spectral Features of Different Types of Long Period Fiber Gratings: Phase-Shifted, Turn-Around Point, Internally Tilted, and Pseudo-Random

“…The first configuration consists of grating planes steadily tilted with a certain angle with respect to the propagation direction of the light; this configuration has been extensively used in FBGs with tilt angles from 4°-10° up to 80°-85° [19][20][21][22]. The second configuration consists of a defect in the central grating plane by splitting the standard grating into two identical sub-gratings with a half-period phase difference between them; this configuration is called "phaseshifted" and has been used in both FBGs and LPFGs [23,24].…”