Sensing and Demodulation of Special Long-Period Fiber Gratings Induced by Scanning CO2 Laser Pulses

Abstract EN

A review of long-period fiber gratings (LPFGs) with special structures induced by scanning CO2 laser pulses in single mode fiber (SMF) is presented in this paper.

In the first part, the special structures and fabrication methods of LPFGs are demonstrated in detail.

Next, the special LPFG-based sensors are demonstrated, such as refractive index sensor, strain sensor with temperature compensation, and torsion sensor without temperature crosstalking.

Finally, several investigation methods including intensity, wavelength shift, and fiber ring laser demodulation are discussed.