Miniature High-Frequency Response, High- Pressure -Range Dynamic Pressure Sensor Based on All-Silica Optical Fiber Fabry-Perot Cavity

A miniature shock-wave pressure sensor based on an optical-fiber tip F-P cavity is described. The basic theory and fabrication process of this sensor are given. The transient interferometric phase of this F-P cavity under the action of a shock pressure wave is demodulated by using the passive homodyne demodulation technique. The static and dynamic calibration test are conducted using piston-type pressure calibration machine and air shock tube. The results indicate that the linearity, repeatability, and hysteresis of the sensor within the 1 MPa pressure range are 4.33%, 1.9%, and 2.8%, respectively, and that the resonant frequency is 8.97 MHz. Pressure sensors in the same package is used to measure the blast wave pressure from pre-charged pneumatic. The pressure probe of the ultra-fine package is used to accurately measure the shock wave pressure produced by the focused electromagnetic shock wave source. The results indicate that different pressure sensors with different diaphragm thickness and different packaging forms can measure shock waves with different ranges and rise times.