Research On Fiber Fabry-perot Pressure Sensor Of Strain Type

Fiber Fabry-Perot sensors can be used in the complicated environment as they have some advantages, such as small size, high temperature resistance, corrosion resistance. In this paper, two package schemes of pressure sensor are proposed on the basis of micro-FP sensor fabricated by 157 nm laser.This paper contains two package schemes of pressure sensor:(1) Based on the circular flat diaphragm structure, a package scheme of pressure sensor is proposed. The stress characteristics of circular flat diaphragm under the uniform load are investigated using ANSYS software. To achieve pressure measurement, a fiber Fabry-Perot sensor is installed on quartz plate. The experiment result shows that the pressure sensor has a sensitivity of 3.17 rad/MPa and a linearity of 0.999 from 0 MPa to 0.2 MPa.(2) Based on the beam-membrane structure, a package scheme of pressure sensor is also proposed. The stress characteristics of circular beam-membrane under the uniform load are investigated using ANSYS software, and the suitable size of beam is obtained from the simulation results. In order to contrast the difference of two structures, two fiber Fabry-Perot sensors are respectively installed on circular flat diaphragm and beam-membrane. The experiment result shows that the fiber Fabry-Perot pressure sensor with circular flat diaphragm structure has a sensitivity of 1.34 rad/MPa and a linearity of 0.999 from 0 MPa to 1 MPa; and the fiber Fabry-Perot pressure sensor with beam-membrane structure has the sensitivity of 1.038 rad/MPa and a linearity of 0.999 from 0 MPa to 1.6 MPa. Compared with circular flat diaphragm, the pressure sensor with beam-membrane structure could increase the range of pressure sensor.