Multipoint Vibration Measurement Using Fabry-Perot Interferometers Consisting of Low-reflective Fiber Bragg Gratings Interrogated by Current Modulated Laser Diode

We present a multipoint vibration sensing system using fiber Fabry-Perot interferometers consisting of low-reflective fiber Bragg gratings (FBG-FPI) and a current-modulated laser diode. The lasing wavelength of a laser diode can be modulated by changing the injection current. Therefore, high-speed current modulation makes possible to achieve high-speed wavelength sweep exceeding 100 kHz. Using a current modulated laser diode as the source for interrogation of FBG-FPI sensor array, high-speed multipoint vibration measurement can be realized.