Temperature characterisation of long‐period gratings for sensor applications

Adhesive‐fixed microbend long‐period fiber gratings with bandpass filter response

“…Regarding the quantization lobe, feeding antenna elements to cause a quadratic phase distribution across the array can reduce the level of quantization lobes as a result of it breaking up the periodicity of phase error on the array [1]. A phase randomization method [3] can also effectively reduce the quantization lobes.…”

“…Long-period fiber gratings (LPFGs) are currently receiving considerable interest in fiber sensor applications as the resonance wavelength is highly sensitive to ambient condition compared to that of fiber Bragg gratings [1][2][3]. They also have the advantage of large easy-to-control grating period that allows a wide variety of production methods of the device, such as deep UV laser radiation, femtosecond laser radiation, electric arc discharge, and mechanical bending [1,[4][5][6][7].…”

Novel sol-gel material for fabrication of a long period waveguide grating filter as a precise thermometer

“…Much research efforts have been devoted to the study of long-period fiber gratings (LPFGs), which can transfer light energy from the guide mode to the selected cladding modes of the fiber at specific resonance wavelength. One of the most important applications of LPGs is temperature sensors [1]. But it is worth nothing that the resonance wavelength of an ordinary LPFG, written in a conventional communication fiber, shifts by only 3-10 nm for a temperature change of 100°C , which is not sufficient for many applications.…”