Ultrashort Long-Period Fiber Gratings Inscribed on a Single-Mode Fiber for Torsion Sensing Applications

Table 1

Values of sensitivity found in literature for torsion measurement for simple LPFGs or other LPFG-based configurations.

Reference	Sensitivity (nm/(rad/m))	Grating length (mm)
Deng et al. [1]	0.1604	9.84
Li et al. [2]	~0.593–~0.94
Zhang et al. [3]	0.115	17.1
Zhou et al. [4]	1.071–2.392
Rao et al. [9]	0.2244	40
Wang and Rao [10]	~0.0645	20
Rao et al. [11]	0.0645	19.6
Wang and Rao [12]	0.024	27
Shi et al. [13]	0.084
Dong et al. [14]	0.1187–0.1817

Not specified.