Electro-optics of bipolar nematic liquid crystal droplets.

We directly visualize the response and relaxation dynamics of bipolar nematic liquid crystal droplets to an applied electric field E. Despite strong planar anchoring, there is no critical field for switching. Instead, upon application of E, the surface region first reorients, followed by movement of the disclinations and the bipolar axis. After removing E, elastic forces restore the drop to its original state. The collective electro-optic properties of ordered hexagonal-close-packed monolayers of drops are probed by diffraction experiments confirming the proposed switching mechanism.