Laser beam steering in a variable gradient index nematic liquid crystal structure

Abstract

We have fabricated a parallel slab of nematic liquid crystal with hybrid alignment that provides “longitudinal” gradient of refractive index for the extraordinary polarized beam. This in turn generates continuously changing angular separation between ordinary and extraordinary beams while propagating inside the slab, like the optical mirage effect. For the moment the output separation angle is not large (below 1°), but it can be further optimized to obtain larger separation angles and consequently more effective electrical control.