Numerical Analysis and Optimal Design of All-Optical Fiber Differential Acceleration Sensor

In order to improve the sensitivity of measurement and realize its miniaturization, an all-optical fiber differential acceleration sensor is studied. This sensor adopts a novel four-port ring fiber coupler, which can realizes the difference of optical signals and the isolation of light source and optical signal. Therefore, the sensitivity of this sensor is doubled compared with that of traditional fiber sensors. The stress–strain relationship simulation results of the sensor probe model show that with the increase of the measured acceleration value, the relative sensitivity, relative resolution, and relative error of the sensor all decrease. In the structural parameters of the probe-sensitive unit, the film thickness has the greatest influence on the performance of the sensor. The radius of the diaphragm 65 μm, a thickness of 2 μm, taking the thickness of the center of mass 20 μm, the mass 20 μm taken radius conditions, sensitivity of this fiber acceleration sensor is not less than 0.0025 m–1 · s2, less than 2% error, the linear measuring range of 0 to 2800 m · s–2. This design combines microelectronics and optical fiber technology, which can more easily realize the miniaturization and multi-function of acceleration sensor.