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Optical fiber sensor has great advantage for applications dealing with extreme environment. We developed a high precision optical pressure sensor for aviation industry. The optical pressure sensor is based on two-beam interference of microcavity and is fabricated with Micro-electromechanical systems (MEMS) and laser fusion technology. The cavity length variation resulting from external pressure is demodulated with spatial polarization low coherence interference unit and a high stable phase demodulation algorithm. The effect of light source output parameter is also investigated. We carried out research on optical fiber strain, temperature and acoustic vibration sensor for aerospace application. The optical fiber sensors for strain and temperature measurement are based on fiber Bragg grating(FBG).Both bare FBG and packaged FBG performances under cryogenic temperature and high vacuum are investigated. An eight-channel parallel FBG wavelength interrogator is developed. The optical fiber acoustic vibration sensor is based on two-beam interference of microcavity and use intensity demodulation method for high speed response. The mutiple-parameter and multiplepoint measurement instrument is successfully applied to status monitoring of water sublimator.

We investigated the fiber Bragg grating (FBG) thermal response in space vacuum thermal environment. The FBGs were packaged with 6061-T6 aluminum. The liquid nitrogen immersion experiment results show that its wavelength shift standard deviation is 0.76 pm for 217 h. The combination effect of vacuum and cryogenic temperature was studied by thermal cycling process in space environment simulator. The FBG sensors show accuracy better than 2% full scale, and the hysteresis errors are below 1%. It proves that these metal packaged FBG sensors can survive and meet the requirement of space measurement.