Ultrathin FBG Pressure Sensor With Enhanced Responsivity

An ultrathin fiber Bragg grating pressure sensor with enhanced sensitivity is demonstrated. A novel piston-like diaphragm with a hard core in the center is used as the sensing element to enhance the responsivity. Both the theoretical analysis and the experimental results show that the Young´s modulus of the diaphragm and the radius of the hard core have significant effect on the pressure responsivity. By optimizing these two parameters, a pressure responsivity of 7 nm/MPa has been achieved.