Three parameter measurement using a single fiber Bragg grating inscribed in Er3 :Yb3 -codoped fiber
CM Rollinson, S Trpkovski, SA Wade, NM Dragomir, GW Baxter, SF Collins
Proceedings of SPIE - The International Society for Optical Engineering | Published : 2005
A fiber Bragg grating was written, using the phase mask technique, in a short length of Er3+:Yb3+-codoped fibre and its temperature and strain characteristics were investigated. Two of the three parameters of interest are associated with Bragg grating properties, namely the usual dip at the Bragg wavelength, λB, and an unexpected dip at ∼2/3 λB that is the third harmonic of features within the grating having double the assumed periodicity. The third parameter is the fluorescence intensity ratio arising from a pair of transitions in Yb 3+ ions. This arrangement consisting of three colocated sensors offers interesting possibilities for the simultaneous measurement of three parameters.