TW201144773A - Fiber sensing system - Google Patents

Abstract

A fiber sensing system includes a reference wavelength filter, at least one sensing fiber Bragg grating (FBG), an optical amplification resonance cavity and a signal processing computer host, the reference wavelength filter can be used as a reference FBG and provide a reference signal wavelength, the sensing FBG is placed on test sites to measure temperature, pressure, deformation and other physical changes for use as basis to change the reflected wavelength of itself, the optical amplification resonance cavity is regulated by the reflected wavelength difference between the reference signal wavelength and the sensor signal, and the wavelength shift of the sensing FBG is directly converted into a resonant cavity light intensity, and output to the signal processing computer host to calculate the physical changes actually measured by the sensing FBG, thereby enabling the invention to make extensive use of FBG in demodulation of wavelength shift without using expensive spectrometer, it can be used in a variety of physical measurement environments, in addition, its advantage is that the optical signal can be amplified in the optical cavity, and suitable in long-distance sensing systems.