Temperature-Independent Force Sensor Based on PSLPFG Induced by Electric-Arc Discharge

A novel approach to create a phase shift in a long period fiber grating (LPFG) by using the electric-arc discharge technique is first proposed and demonstrated. We observe that an equivalent phase shift is created at the middle of the LPFG by slight tapering the grating by discharge arc. By measuring the wavelength separation of the two resonance peaks, we obtain a force sensor without any temperature crosstalk.