Reversible color switching from blue to red in a polymer stabilized chiral nematic liquid crystals

In this letter, the authors demonstrate reversible color switching from blue to red in polymer stabilized chiral nematic liquid crystals when viewed at oblique angles. A series of unusual colored scattering states, different from those noted in polymer-free samples, was observed in cells that had been prepared using a technique of cooling the sample from the isotropic phase in the presence of a low frequency (80 Hz) applied electric field and then photopolymerizing the sample on both sides of the cell. This process freezes-in a texture whereby the helix axis lies preferentially in the plane of the cell. (c) 2007 American Institute of Physics.