Polarimetric multilongitudinal-mode distributed Bragg reflector fiber laser sensor for strain measurement

A polarimetric multilongitudinal‐mode distributed Bragg reflector fiber laser sensor is proposed and experimentally demonstrated. We have theoretically analyzed the mode beat mechanism of this laser sensor, which is verified by the experimental observation, and its application in strain measurement has also been studied. Experimental results indicate that both of the longitudinal mode beat (LMB) and birefringence‐induced polarization mode beat signals have linear strain dependence, and the coefficients of determination reach 0.9991 and 0.9908, respectively. One possible way to improve the sensitivity of LMB‐based sensing has been investigated as well. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 2559–2563, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24671