DESIGN OF SURFACES FOR PATTERNED ALIGNMENT OF LIQUID-CRYSTALS ON PLANAR AND CURVED SUBSTRATES

Molecularly designed surfaces formed by chemisorption of alkanethiols on ultrathin films of gold permit control of both the azimuthal and po lar orientations of supported nematic liquid crystals (LCs). These sur faces, when patterned, form simple and versatile templates for the fab rication of complex optical structures from LCs. Surfaces patterned wi th odd or even alkanethiols, or mixtures of tong and short alkanethiol s, were used to fabricate tunable, micrometer-scale LC diffraction gra tings that differed in their polarization sensitivity. Patterned align ment of LCs on curved surfaces is also demonstrated, thereby providing principles for fabrication of optical elements that combine diffracti ve and refractive optics.