FBG sensor system

A Fiber Bragg Grating (FBG) sensor system comprising:

• a wavelength-tunable light source for outputting light wavelength-swept at a predetermined sweep period by using a semiconductor laser, the light including light in a predetermined wavelength range;
• a photodetector for operating in a manner that, upon receipt of reflected light of measurement light directed to be incident on an optical fiber including an FBG having reflection wavelength falling within the range of the wavelength sweep, the photodetector converts the reflected light to an electric signal;
• a processing unit for measuring the reflection wavelength of the FBG in accordance with the electric signal output from the photodetector;
• and
• optical pulse generator means including a pulse generator that generates a pulse having a predetermined period in synchronism with the sweep period, the optical pulse generator means being connected to the wavelength-tunable light source in order that the light from the wavelength-tunable light source is converted into an optical pulse formed of light in the predetermined wavelength range by using the pulse and the optical pulse is directed to be incident on the optical fiber,
• wherein
• the sweep period is such that a receipt time of the reflected light relative to the optical pulse as the measurement light in the photodetector from the FBG is after termination of incidence of the optical pulse on the optical fiber, and
• the predetermined period of the pulse is such that an incidence time for incidence of a next optical pulse following the optical pulse as the measurement light on the optical fiber is after receipt of the reflected light relative to the optical pulse in the photodetector from the FBG.