Simultaneous measurement of vibration and temperature using a Fabry-Perot interferometer in polarization maintaining fiber and laser diodes

High-resolution simultaneous measurement of vibration and temperature using an optical fiber sensor is presented. Strain and temperature can be measured simultaneously by using two types of reflection spectra of a Fabry-Perot interferometer consisted of fiber Bragg gratings in a polarization maintaining fiber. The fine structure of reflection spectrum of the interferometer, i.e. PM-FBG-FPI, enables high-resolution detection of wavelength shifts. In order to measure solid vibration, we present a fast interrogation method using current modulation of a laser diode for PM-FBG-FPI sensors. The resulting fast measurement is demonstrated experimentally.