LAUSR

Abstract A highly sensitive fiber Bragg grating (FBG) based square diaphragm pressure sensor has been designed and verified both in theory and experiment. The square diaphragm deflects due to the pressure difference generated at both sides of the square, and causes the compression along the axis of the pre-stretched FBG. The experimental results indicate that the pressure sensitivity of the proposed sensor reaches 3.402 pm/kPa in the range of 0–200 kPa with a higher coefficient of determination of 0.9985. Meanwhile, the sensor is found to present low hysteresis, good repeatability and resolution. Relative error recorded at 3.13 % represents that the effect of the temperature compensation is remarkable. Furthermore, the designed pressure sensor is simple, cost-effective and suitable for low pressure measurement.