Brillouin fibre laser discrete sensor for simultaneous strain and temperature measurement

In this work, a Brillouin fibre laser sensor for strain and temperature discrimination is presented. The fibre laser sensor consists of a Fabry-Perot cavity with 20 m of optical fibre between two Bragg gratings. For the strain measurement, the 20 m were split in half and in 10 m a pre-tension was applied originating two Brillouin peaks. For the temperature measurement all of the sensing head was heated. The resolutions achieved were +/- 1 mu epsilon and +/- 1 degrees C for strain and temperature measurements, respectively.