DBR-FIBER-LASER-BASED ACTIVE TEMPERATURE SENSOR AND ITS APPLICATIONS IN THE MEASUREMENT OF FIBER BIREFRINGENCE

A fiber active temperature sensor based on single-longitudinal-mode distributed Bragg reflector (DBR) fiber laser is proposed and experimentally demonstrated. The dual-polarization mode DBR fiber laser could be employed as a temperature sensor through beat frequency interrogation. The temperature sensitivities of this polarimetric sensor are experimentally compared both through frequency and wavelength interrogations. By calculating the fiber birefringence at different temperature, temperature dependence of fiber birefringence is also investigated. Theoretical analysis and experiment results indicate that the fiber birefringence would linearly decrease with the increase of temperature. Based on the frequency and wavelength interrogations, respectively, the fiber active sensor would provide an effective way to achieve simultaneous measurement of multi-parameters. (C) 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 41-44, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24820