Particle free optical imaging of flow field by liquid crystal polarization.

This paper proposes and demonstrates a particle free method for flow field visualizations by analyzing liquid crystal polarizations. The proposed concept is implemented by imaging of liquid crystal flow under microfluidic environment using a crossed polarization microscopy configuration. Fringe patterns give good representation of flow characterizations for different nozzle/diffuser microchannel designs. The obtained results demonstrate that the flow field under various conditions can be evaluated. Visualizations of the flow fields are carried out by the liquid crystal polarization induced fringe patterns in nozzle/diffuser microchannels. We achieve good match between the flow field obtained by LC polarization and the simulated one. It is envisaged that the proposed methodology can make a potential impact in flow field visualization studies and related analysis.