Liquid crystal microlens arrays recorded by polarization holography.

We report the characterization of diffractive microlens arrays (MAs) using a polarization holographic approach assisted by a spatial light modulator (SLM), in a nematic liquid crystal (NLC) cell. The MAs were recorded in the photoaligning substrates of the cell and then replicated in the NLC bulk, through the surface interactions. The transparency of the NLC on a wide range of wavelengths and the ability to tune its optical birefringence, through an external voltage, allowed us to create MAs with high efficiency.

Enantiomeric guests with the same signs of chiral optical responses.

The circular dichroism of non-racemic molecules, being guests of co-crystalline phases of s-PS films, has been studied. Unexpectedly, the chiral response of non-racemic guest molecules does not depend on their R or S molecular chirality but essentially only on the polymer host supramolecular chirality.