FIBER LASER SOURCE ANALYZER FOR BRAGG GRATING SENSOR ARRAY INTERROGATION

This paper reports on the application of a calibrated, narrow-linewidt h, single-frequency, continuously wavelength-tunable erbium fiber lase r to the interrogation of a multipoint Bragg grating temperature senso r. The fiber laser was wavelength-tuned, through an array of three fib er Bragg grating sensors, to determine the temperature of each individ ual grating. The temperatures of the three gratings were measured as a function of grating Bragg wavelength. The minimum wavelength resoluti on, due to electro-mechanical repeatability, of the fiber laser source /analyzer was determined to be approximately 2.3 picometers. This corr esponds to a frequency resolution of approximately 300 MHz.