Vibration-based specklegram fiber sensor for measurement of properties of liquids

► Specklegram fiber sensor for the measurement of properties of liquids is proposed. ► Transducer placed in liquid is excited by vibration and modulates speckle fields. ► Speckles correlated to properties of ethanol-water samples by neural networks. ► Error lower than 0.5 g is obtained in the measurement of mass. ► Error lower than 0.1 mPa s is obtained in the measurement of viscosity.