Acoustically modulated long period grating sensor for simultaneous viscosity and density measurement
R. A. Oliveira, Federal University of Technology - Paraná (Brazil); M. Naqshbandi, K. Cook, J. Canning, University of Sydney (Australia); A. A. P. Pohl, Federal University of Technology - Paraná (Brazil)
Acoustic waves, generated by exploiting the acousto-optic effect within silica optical fibres, were used to enhance the sensitivity of a long period grating. Most of the physical parameters measured by using an LPG involve simple linear and passive transformations of spectral shifts. However, by adding a temporal element using acoustic waves, parameters that require dynamic assessment become accessible. In this work we demonstrate the measurement of fluid viscosity by measuring the rise time and acousto-optic efficiency. We show results of sensor characterization and suggest the possibility of monitoring a chemical reaction in real time.
