Title :
Frequency-shifted multiwavelength FBG laser sensor
Author :
Yamashita, Shinji ; Baba, T. ; Kashiwagi, Ken
Author_Institution :
Dept. of Frontier Informatics, Univ. of Tokyo, Japan
Abstract :
We propose and demonstrate a novel frequency-shifted FBG (fiber Bragg grating) laser sensor system. It is composed of an EDFA (erbium-doped fiber amplifier) broadband light source, 3-FBG array, single mode fiber, circulator, acousto-optic modulator (AOM) and an output 3dB fiber coupler. The frequency-shifted feedback by the AOM allows the laser to operate at multiwavelength at room temperature. Compared to a conventional passive system, the optical signal power and SN ratio were enhanced by 20.1 dB, and 17.0 dB, respectively, and the linewidth was reduced to 1/5.3.
Keywords :
Bragg gratings; acousto-optical modulation; fibre optic sensors; laser feedback; optical circulators; optical fibre amplifiers; 20 degC; AOM frequency shifted feedback; EDFA; FBG array; SN ratio; acousto-optic modulator; broadband light source; circulator; erbium-doped fiber amplifier; fiber Bragg grating; fiber optic coupler; frequency-shifted multiwavelength FBG laser sensor; linewidth; optical signal power; room temperature multiwavelength laser operation; signal to noise ratio; single mode fiber; Bragg gratings; Erbium-doped fiber amplifier; Erbium-doped fiber lasers; Fiber gratings; Frequency; Laser feedback; Laser modes; Optical fiber couplers; Optical fiber sensors; Optical modulation;
Conference_Titel :
Optical Fiber Sensors Conference Technical Digest, 2002. Ofs 2002, 15th
Conference_Location :
Portland, OR, USA
Print_ISBN :
0-7803-7289-1
DOI :
10.1109/OFS.2002.1000558
